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Sample records for estrogen receptor levels

  1. Transcriptional targets shared by estrogen receptor- related receptors (ERRs) and estrogen receptor (ER) alpha, but not by ERbeta.

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    Vanacker, J M; Pettersson, K; Gustafsson, J A; Laudet, V

    1999-01-01

    The physiological activities of estrogens are thought to be mediated by specific nuclear receptors, ERalpha and ERbeta. However, certain tissues, such as the bone, that are highly responsive to estrogens only express a low level of these receptors. Starting from this apparent contradiction, we have evaluated the potentials of two related receptors ERRalpha and ERRbeta to intervene in estrogen signaling. ERalpha, ERRalpha and ERRbeta bind to and activate transcription through both the classical estrogen response element (ERE) and the SF-1 response element (SFRE). In contrast, ERbeta DNA-binding and transcriptional activity is restricted to the ERE. Accordingly, the osteopontin gene promoter is stimulated through SFRE sequences, by ERRalpha as well as by ERalpha, but not by ERbeta. Analysis of the cross-talk within the ER/ERR subgroup of nuclear receptors thus revealed common targets but also functional differences between the two ERs. PMID:10428965

  2. Estrogen, Estrogen Receptor and Lung Cancer

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    Li-Han Hsu

    2017-08-01

    Full Text Available Estrogen has been postulated as a contributor for lung cancer development and progression. We reviewed the current knowledge about the expression and prognostic implications of the estrogen receptors (ER in lung cancer, the effect and signaling pathway of estrogen on lung cancer, the hormone replacement therapy and lung cancer risk and survival, the mechanistic relationship between the ER and the epidermal growth factor receptor (EGFR, and the relevant clinical trials combining the ER antagonist and the EGFR antagonist, to investigate the role of estrogen in lung cancer. Estrogen and its receptor have the potential to become a prognosticator and a therapeutic target in lung cancer. On the other hand, tobacco smoking aggravates the effect of estrogen and endocrine disruptive chemicals from the environment targeting ER may well contribute to the lung carcinogenesis. They have gradually become important issues in the course of preventive medicine.

  3. Evaluation of estrogen and G protein-coupled estrogen receptor 1 (GPER levels in drug-naïve patients with attention deficit hyperactivity disorder (ADHD

    Directory of Open Access Journals (Sweden)

    Nilfer Sahin

    2018-05-01

    Full Text Available Estrogen has a crucial role in the regulation of reproductive and neuroendocrine function and exerts its effects through two classes of receptors, nuclear and membrane estrogen receptors (mERs. G protein-coupled estrogen receptor 1 (GPER is a member of mERs, and despite limited research on the levels of GPER in patients with psychiatric diseases, a role of GPER in such conditions has been suggested. Here we evaluated serum estrogen and GPER levels in children with attention deficit hyperactivity disorder (ADHD in relation to their age- and gender-matched healthy controls. A total of 82 children were included in the study, 47 drug- naïve patients with ADHD (age: 6–12 years; male/female: 34/13 and 35 healthy controls (age: 6–12 years; male/female: 19/16. The subgroups according to ADHD types were inattentive, hyperactive/impulsive, and combined. Serum estrogen was measured using an immunoassay system, while serum GPER was determined using a commercial sandwich enzyme-linked immunosorbent assay kit. Estrogen levels in children with ADHD were similar as in control group, while GPER levels were significantly lower in ADHD group compared to controls (p < 0.05. Logistic regression analysis showed a significant association between GPER levels and ADHD (p < 0.05, and no association between estrogen levels and ADHD (p > 0.05. No significant differences were found in GPER and estrogen levels between ADHD subgroups (p > 0.05. To the best of our knowledge, this study is the first to investigate estrogen and GPER levels in ADHD. Our preliminary findings suggest a relationship between serum GPER levels and ADHD, and this should be further investigated.

  4. No substantial changes in estrogen receptor and estrogen-related receptor orthologue gene transcription in Marisa cornuarietis exposed to estrogenic chemicals.

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    Bannister, Richard; Beresford, Nicola; Granger, David W; Pounds, Nadine A; Rand-Weaver, Mariann; White, Roger; Jobling, Susan; Routledge, Edwin J

    2013-09-15

    Estrogen receptor orthologues in molluscs may be targets for endocrine disruptors, although mechanistic evidence is lacking. Molluscs are reported to be highly susceptible to effects caused by very low concentrations of environmental estrogens which, if substantiated, would have a major impact on the risk assessment of many chemicals. The present paper describes the most thorough evaluation to-date of the susceptibility of Marisa cornuarietis ER and ERR gene transcription to modulation by vertebrate estrogens in vivo and in vitro. We investigated the effects of estradiol-17β and 4-tert-Octylphenol exposure on in vivo estrogen receptor (ER) and estrogen-related receptor (ERR) gene transcription in the reproductive and neural tissues of the gastropod snail M. cornuarietis over a 12-week period. There was no significant effect (p>0.05) of treatment on gene transcription levels between exposed and non-exposed snails. Absence of a direct interaction of estradiol-17β and 4-tert-Octylphenol with mollusc ER and ERR protein was also supported by in vitro studies in transfected HEK-293 cells. Additional in vitro studies with a selection of other potential ligands (including methyl-testosterone, 17α-ethinylestradiol, 4-hydroxytamoxifen, diethylstilbestrol, cyproterone acetate and ICI182780) showed no interaction when tested using this assay. In repeated in vitro tests, however, genistein (with mcER-like) and bisphenol-A (with mcERR) increased reporter gene expression at high concentrations only (>10(-6)M for Gen and >10(-5)M for BPA, respectively). Like vertebrate estrogen receptors, the mollusc ER protein bound to the consensus vertebrate estrogen-response element (ERE). Together, these data provide no substantial evidence that mcER-like and mcERR activation and transcript levels in tissues are modulated by the vertebrate estrogen estradiol-17β or 4-tert-Octylphenol in vivo, or that other ligands of vertebrate ERs and ERRs (with the possible exception of genistein and

  5. Membrane estrogen receptors - is it an alternative way of estrogen action?

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    Soltysik, K; Czekaj, P

    2013-04-01

    The functions of estrogens are relatively well known, however the molecular mechanism of their action is not clear. The classical pathway of estrogen action is dependent on ERα and ERβ which act as transcription factors. The effects of this pathway occur within hours or days. In addition, so-called, non-classical mechanism of steroid action dependent on membrane estrogen receptors (mER) was described. In this mechanism the effects of estrogen action are observed in a much shorter time. Here we review the structure and cellular localization of mER, molecular basis of non-classical mER action, physiological role of mER as well as implications of mER action for cancer biology. Finally, some concerns about the new estrogen receptor - GPER and candidates for estrogen receptors - ER-X and ERx, are briefly discussed. It seems that mER is a complex containing signal proteins (signalosome), as IGF receptor, EGF receptor, Ras protein, adaptor protein Shc, non-receptor kinase c-Src and PI-3K, what rationalizes production of second messengers. Some features of membrane receptors are almost identical if compared to nuclear receptors. Probably, membrane and nuclear estrogen receptors are not separate units, but rather the components of a complex mechanism in which they both cooperate with each other. We conclude that the image of the estrogen receptor as a simple transcription factor is a far-reaching simplification. A better understanding of the mechanisms of estrogen action will help us to design more effective drugs affecting signal pathways depending on both membrane and nuclear receptors.

  6. No substantial changes in estrogen receptor and estrogen-related receptor orthologue gene transcription in Marisa cornuarietis exposed to estrogenic chemicals☆☆☆

    Science.gov (United States)

    Bannister, Richard; Beresford, Nicola; Granger, David W.; Pounds, Nadine A.; Rand-Weaver, Mariann; White, Roger; Jobling, Susan; Routledge, Edwin J.

    2013-01-01

    Estrogen receptor orthologues in molluscs may be targets for endocrine disruptors, although mechanistic evidence is lacking. Molluscs are reported to be highly susceptible to effects caused by very low concentrations of environmental estrogens which, if substantiated, would have a major impact on the risk assessment of many chemicals. The present paper describes the most thorough evaluation to-date of the susceptibility of Marisa cornuarietis ER and ERR gene transcription to modulation by vertebrate estrogens in vivo and in vitro. We investigated the effects of estradiol-17β and 4-tert-Octylphenol exposure on in vivo estrogen receptor (ER) and estrogen-related receptor (ERR) gene transcription in the reproductive and neural tissues of the gastropod snail M. cornuarietis over a 12-week period. There was no significant effect (p > 0.05) of treatment on gene transcription levels between exposed and non-exposed snails. Absence of a direct interaction of estradiol-17β and 4-tert-Octylphenol with mollusc ER and ERR protein was also supported by in vitro studies in transfected HEK-293 cells. Additional in vitro studies with a selection of other potential ligands (including methyl-testosterone, 17α-ethinylestradiol, 4-hydroxytamoxifen, diethylstilbestrol, cyproterone acetate and ICI182780) showed no interaction when tested using this assay. In repeated in vitro tests, however, genistein (with mcER-like) and bisphenol-A (with mcERR) increased reporter gene expression at high concentrations only (>10−6 M for Gen and >10−5 M for BPA, respectively). Like vertebrate estrogen receptors, the mollusc ER protein bound to the consensus vertebrate estrogen-response element (ERE). Together, these data provide no substantial evidence that mcER-like and mcERR activation and transcript levels in tissues are modulated by the vertebrate estrogen estradiol-17β or 4-tert-Octylphenol in vivo, or that other ligands of vertebrate ERs and ERRs (with the possible exception of

  7. Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues.

    Science.gov (United States)

    Philips, Brian J; Ansell, Pete J; Newton, Leslie G; Harada, Nobuhiro; Honda, Shin-Ichiro; Ganjam, Venkataseshu K; Rottinghaus, George E; Welshons, Wade V; Lubahn, Dennis B

    2004-06-01

    Primary evidence for novel estrogen signaling pathways is based upon well-documented estrogenic responses not inhibited by estrogen receptor antagonists. In addition to 17beta-E2, the catechol estrogen 4-hydroxyestradiol (4OHE2) has been shown to elicit biological responses independent of classical estrogen receptors in estrogen receptor-alpha knockout (ERalphaKO) mice. Consequently, our research was designed to biochemically characterize the protein(s) that could be mediating the biological effects of catechol estrogens using enzymatically synthesized, radiolabeled 4-hydroxyestrone (4OHE1) and 4OHE2. Scatchard analyses identified a single class of high-affinity (K(d) approximately 1.6 nM), saturable cytosolic binding sites in several ERalphaKO estrogen-responsive tissues. Specific catechol estrogen binding was competitively inhibited by unlabeled catechol estrogens, but not by 17beta-E2 or the estrogen receptor antagonist ICI 182,780. Tissue distribution studies indicated significant binding differences both within and among various tissues in wild-type, ERalphaKO, and aromatase knockout female mice. Ligand metabolism experiments revealed extensive metabolism of labeled catechol estrogen, suggesting that catechol estrogen metabolites were responsible for the specific binding. Collectively, our data provide compelling evidence for the interaction of catechol estrogen metabolites with a novel binding protein that exhibits high affinity, specificity, and selective tissue distribution. The extensive biochemical characterization of this binding protein indicates that this protein may be a receptor, and thus may mediate ERalpha/beta-independent effects of catechol estrogens and their metabolites.

  8. Retinoid X receptor and peroxisome proliferator-activated receptor activate an estrogen responsive gene independent of the estrogen receptor.

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    Nuñez, S B; Medin, J A; Braissant, O; Kemp, L; Wahli, W; Ozato, K; Segars, J H

    1997-03-14

    Estrogen receptors regulate transcription of genes essential for sexual development and reproductive function. Since the retinoid X receptor (RXR) is able to modulate estrogen responsive genes and both 9-cis RA and fatty acids influenced development of estrogen responsive tumors, we hypothesized that estrogen responsive genes might be modulated by RXR and the fatty acid receptor (peroxisome proliferator-activated receptor, PPAR). To test this hypothesis, transfection assays in CV-1 cells were performed with an estrogen response element (ERE) coupled to a luciferase reporter construct. Addition of expression vectors for RXR and PPAR resulted in an 11-fold increase in luciferase activity in the presence of 9-cis RA. Furthermore, mobility shift assays demonstrated binding of RXR and PPAR to the vitellogenin A2-ERE and an ERE in the oxytocin promoter. Methylation interference assays demonstrated that specific guanine residues required for RXR/PPAR binding to the ERE were similar to residues required for ER binding. Moreover, RXR domain-deleted constructs in transfection assays showed that activation required RXR since an RXR delta AF-2 mutant completely abrogated reporter activity. Oligoprecipitation binding studies with biotinylated ERE and (35)S-labeled in vitro translated RXR constructs confirmed binding of delta AF-2 RXR mutant to the ERE in the presence of baculovirus-expressed PPAR. Finally, in situ hybridization confirmed RXR and PPAR mRNA expression in estrogen responsive tissues. Collectively, these data suggest that RXR and PPAR are present in reproductive tissues, are capable of activating estrogen responsive genes and suggest that the mechanism of activation may involve direct binding of the receptors to estrogen response elements.

  9. The relationship between ovarian steroids and uterine estrogen receptors during late pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Cathey, T.M.; Chung, Kyung W. (Univ. of Oklahoma, Oklahoma City (USA))

    1991-01-01

    Although a direct interdependence exists between the ovarian steroids, estrogen and progesterone, the exact role of these two hormones during pregnancy, especially late pregnancy, is not completely understood. Investigations have been conducted to determine whether the circulating levels of progesterone and estrogen or changes in the ratio of progesterone/estrogen in relation to the concentration of uterine estrogen receptors are associated with triggering parturition. Ninety-day old female rats were sacrificed at gestation days 14, 16, 18, 20 and two days post-partum. The plasma levels of estradiol and progesterone were measured by solid-phase radioimmunoassay. Uterine cytosol was subjected to a charcoal binding assay to determine the concentration of estrogen receptors. Our findings demonstrate that there is a significant drop in both plasma progesterone and estradiol during late pregnancy. Also indicated is a significant increase in uterine estrogen receptors throughout late pregnancy. Finally, during this period there is a direct correlation between the shift in the progesterone/estrogen ratio and the increase in the concentration of uterine estrogen receptors in late pregnancy.

  10. The relationship between ovarian steroids and uterine estrogen receptors during late pregnancy

    International Nuclear Information System (INIS)

    Cathey, T.M.; Chung, Kyung W.

    1991-01-01

    Although a direct interdependence exists between the ovarian steroids, estrogen and progesterone, the exact role of these two hormones during pregnancy, especially late pregnancy, is not completely understood. Investigations have been conducted to determine whether the circulating levels of progesterone and estrogen or changes in the ratio of progesterone/estrogen in relation to the concentration of uterine estrogen receptors are associated with triggering parturition. Ninety-day old female rats were sacrificed at gestation days 14, 16, 18, 20 and two days post-partum. The plasma levels of estradiol and progesterone were measured by solid-phase radioimmunoassay. Uterine cytosol was subjected to a charcoal binding assay to determine the concentration of estrogen receptors. Our findings demonstrate that there is a significant drop in both plasma progesterone and estradiol during late pregnancy. Also indicated is a significant increase in uterine estrogen receptors throughout late pregnancy. Finally, during this period there is a direct correlation between the shift in the progesterone/estrogen ratio and the increase in the concentration of uterine estrogen receptors in late pregnancy

  11. Impact of Estrogens and Estrogen Receptor Alpha (ESR1) in Brain Lipid Metabolism.

    Science.gov (United States)

    Morselli, Eugenia; de Souza Santos, Roberta; Gao, Su; Ávalos, Yenniffer; Criollo, Alfredo; Palmer, Biff F; Clegg, Deborah J

    2018-03-06

    Estrogens and their receptors play key roles in regulating body weight, energy expenditure, and metabolic homeostasis. It is known that lack of estrogens promotes increased food intake and induces the expansion of adipose tissues, for which much is known. An area of estrogenic research that has received less attention is the role of estrogens and their receptors in influencing intermediary lipid metabolism in organs such as the brain. In this review, we highlight the actions of estrogens and their receptors in regulating their impact on modulating fatty acid content, utilization, and oxidation through their direct impact on intracellular signaling cascades within the central nervous system.

  12. A recombinant estrogen receptor fragment-based homogeneous fluorescent assay for rapid detection of estrogens.

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    Wang, Dan; Xie, Jiangbi; Zhu, Xiaocui; Li, Jinqiu; Zhao, Dongqin; Zhao, Meiping

    2014-05-15

    In this work, we demonstrate a novel estrogenic receptor fragment-based homogeneous fluorescent assay which enables rapid and sensitive detection of 17β-estradiol (E2) and other highly potent estrogens. A modified human estrogenic receptor fragment (N-His × 6-hER270-595-C-Strep tag II) has been constructed that contains amino acids 270-595 of wild-type human estrogenic receptor α (hER270-595) and two specific tags (6 × His and Strep tag II) fused to the N and C terminus, respectively. The designed receptor protein fragment could be easily produced by prokaryotic expression with high yield and high purity. The obtained protein exhibits high binding affinity to E2 and the two tags greatly facilitate the application of the recombinant protein. Taking advantage of the unique spectroscopic properties of coumestrol (CS), a fluorescent phytoestrogen, a CS/hER270-595-based fluorescent assay has been developed which can sensitively respond to E2 within 1.0 min with a linear working range from 0.1 to 20 ng/mL and a limit of detection of 0.1 ng/mL. The assay was successfully applied for rapid detection of E2 in the culture medium of rat hippocampal neurons. The method also holds great potential for high-throughput monitoring the variation of estrogen levels in complex biological fluids, which is crucial for investigation of the molecular basis of various estrogen-involved processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Genomic agonism and phenotypic antagonism between estrogen and progesterone receptors in breast cancer

    OpenAIRE

    Singhal, Hari; Greene, Marianne E.; Tarulli, Gerard; Zarnke, Allison L.; Bourgo, Ryan J.; Laine, Muriel; Chang, Ya-Fang; Ma, Shihong; Dembo, Anna G.; Raj, Ganesh V.; Hickey, Theresa E.; Tilley, Wayne D.; Greene, Geoffrey L.

    2016-01-01

    The functional role of progesterone receptor (PR) and its impact on estrogen signaling in breast cancer remain controversial. In primary ER+ (estrogen receptor?positive)/PR+ human tumors, we report that PR reprograms estrogen signaling as a genomic agonist and a phenotypic antagonist. In isolation, estrogen and progestin act as genomic agonists by regulating the expression of common target genes in similar directions, but at different levels. Similarly, in isolation, progestin is also a weak ...

  14. Microarray-Based Determination of Estrogen Receptor, Progesterone Receptor, and HER2 Receptor Status in Breast Cancer

    NARCIS (Netherlands)

    Roepman, Paul; Horlings, Hugo M.; Krijgsman, Oscar; Kok, Marleen; Bueno-de-Mesquita, Jolien M.; Bender, Richard; Linn, Sabine C.; Glas, Annuska M.; van de Vijver, Marc J.

    2009-01-01

    Purpose: The level of estrogen receptor (ER), progesterone receptor (PR), and HER2 aids in the determination of prognosis and treatment of breast cancer. Immunohistochemistry is currently the predominant method for assessment, but differences in methods and interpretation can substantially affect

  15. In vivo imaging of estrogen receptor concentration in the endometrium and myometrium using FES PET - influence of menstrual cycle and endogenous estrogen level

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchida, Tatsuro [Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan)]. E-mail: tsucchy@fmsrsa.fukui-med.ac.jp; Okazawa, Hidehiko [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Mori, Tetsuya [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Kobayashi, Masato [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Yoshida, Yoshio [Department of Obstetrics and Gynecology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Fujibayashi, Yasuhisa [Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan); Itoh, Harumi [Department of Radiology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Fukui 910-1193 (Japan)

    2007-02-15

    Purpose: The goals of this study were to measure estrogen receptor (ER) concentration in the endometrium and myometrium using 16{alpha}-[{sup 18}F]fluoro-17{beta}-estradiol (FES) positron emission tomography (PET) and to investigate the relationship between changes in these parameters with the menstrual cycle and endogenous estrogen levels. Methods: Sixteen female healthy volunteers were included in this study. After blood sampling to measure endogenous estrogen level, FES PET image was acquired 60 min postinjection of FES. After whole-body imaging of FES PET, averaged standardized uptake values (SUVs) in the endometrium and myometrium were measured, and the relationship between FES uptake and menstrual cycle or endogenous estrogen level was evaluated. Results: Endometrial SUV was significantly higher in the proliferative phase than in the secretory phase (6.03{+-}1.05 vs. 3.97{+-}1.29, P=.022). In contrast, there was no significant difference in myometrial SUV when the proliferative and secretory phases were compared (P=.23). Further, there was no correlation between SUV and endogenous estrogen level in the proliferative phase. Conclusions: The change of ER concentration relative to menstrual cycle as characterized by FES PET was consistent with those from previous reports that used an immunohistochemical technique. These data suggest that FES PET is a feasible, noninvasive method for characterizing changes in ER concentration.

  16. In vivo imaging of estrogen receptor concentration in the endometrium and myometrium using FES PET - influence of menstrual cycle and endogenous estrogen level

    International Nuclear Information System (INIS)

    Tsuchida, Tatsuro; Okazawa, Hidehiko; Mori, Tetsuya; Kobayashi, Masato; Yoshida, Yoshio; Fujibayashi, Yasuhisa; Itoh, Harumi

    2007-01-01

    Purpose: The goals of this study were to measure estrogen receptor (ER) concentration in the endometrium and myometrium using 16α-[ 18 F]fluoro-17β-estradiol (FES) positron emission tomography (PET) and to investigate the relationship between changes in these parameters with the menstrual cycle and endogenous estrogen levels. Methods: Sixteen female healthy volunteers were included in this study. After blood sampling to measure endogenous estrogen level, FES PET image was acquired 60 min postinjection of FES. After whole-body imaging of FES PET, averaged standardized uptake values (SUVs) in the endometrium and myometrium were measured, and the relationship between FES uptake and menstrual cycle or endogenous estrogen level was evaluated. Results: Endometrial SUV was significantly higher in the proliferative phase than in the secretory phase (6.03±1.05 vs. 3.97±1.29, P=.022). In contrast, there was no significant difference in myometrial SUV when the proliferative and secretory phases were compared (P=.23). Further, there was no correlation between SUV and endogenous estrogen level in the proliferative phase. Conclusions: The change of ER concentration relative to menstrual cycle as characterized by FES PET was consistent with those from previous reports that used an immunohistochemical technique. These data suggest that FES PET is a feasible, noninvasive method for characterizing changes in ER concentration

  17. Identification of an estrogenic hormone receptor in Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Mimoto, Ai; Fujii, Madoka; Usami, Makoto; Shimamura, Maki; Hirabayashi, Naoko; Kaneko, Takako; Sasagawa, Noboru; Ishiura, Shoichi

    2007-01-01

    Changes in both behavior and gene expression occur in Caenorhabditis elegans following exposure to sex hormones such as estrogen and progesterone, and to bisphenol A (BPA), an estrogenic endocrine-disrupting compound. However, only one steroid hormone receptor has been identified. Of the 284 known nuclear hormone receptors (NHRs) in C. elegans, we selected nhr-14, nhr-69, and nhr-121 for analysis as potential estrogenic hormone receptors, because they share sequence similarity with the human estrogen receptor. First, the genes were cloned and expressed in Escherichia coli, and then the affinity of each protein for estrogen was determined using a surface plasmon resonance (SPR) biosensor. All three NHRs bound estrogen in a dose-dependent fashion. To evaluate the specificity of the binding, we performed a solution competition assay using an SPR biosensor. According to our results, only NHR-14 was able to interact with estrogen. Therefore, we next examined whether nhr-14 regulates estrogen signaling in vivo. To investigate whether these interactions actually control the response of C. elegans to hormones, we investigated the expression of vitellogenin, an estrogen responsive gene, in an nhr-14 mutant. Semi-quantitative RT-PCR showed that vitellogenin expression was significantly reduced in the mutant. This suggests that NHR-14 is a C. elegans estrogenic hormone receptor and that it controls gene expression in response to estrogen

  18. The anticancer estrogen receptor antagonist tamoxifen impairs consolidation of inhibitory avoidance memory through estrogen receptor alpha.

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    Lichtenfels, Martina; Dornelles, Arethuza da Silva; Petry, Fernanda Dos Santos; Blank, Martina; de Farias, Caroline Brunetto; Roesler, Rafael; Schwartsmann, Gilberto

    2017-11-01

    Over two-thirds of women with breast cancer have positive tumors for hormone receptors, and these patients undergo treatment with endocrine therapy, tamoxifen being the most widely used agent. Despite being very effective in breast cancer treatment, tamoxifen is associated with side effects that include cognitive impairments. However, the specific aspects and mechanisms underlying these impairments remain to be characterized. Here, we have investigated the effects of tamoxifen and interaction with estrogen receptors on formation of memory for inhibitory avoidance conditioning in female rats. In the first experiment, Wistar female rats received a single oral dose of tamoxifen (1, 3, or 10 mg/kg) or saline by gavage immediately after training and were tested for memory consolidation 24 h after training. In the second experiment, rats received a single dose of 1 mg/kg tamoxifen or saline by gavage 3 h after training and were tested 24 h after training for memory consolidation. In the third experiment, rats received a subcutaneous injection with estrogen receptor α agonist or estrogen receptor beta agonist 30 min before the training. After training, rats received a single oral dose of tamoxifen 1 mg/kg or saline and were tested 24 h after training. In the fourth experiment, rats were trained and tested 24 h later. Immediately after test, rats received a single dose of tamoxifen (1 mg/kg) or saline by gavage and were given four additional daily test trials followed by a re-instatement. Tamoxifen at 1 mg/kg impaired memory consolidation when given immediately after training and the estrogen receptor alpha agonist improved the tamoxifen-related memory impairment. Moreover, tamoxifen impairs memory consolidation of the test. These findings indicate that estrogen receptors regulate the early phase of memory consolidation and the effects of tamoxifen on memory consolidation.

  19. Oleocanthal Modulates Estradiol-Induced Gene Expression Involving Estrogen Receptor α.

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    Keiler, Annekathrin Martina; Djiogue, Sefirin; Ehrhardt, Tino; Zierau, Oliver; Skaltsounis, Leandros; Halabalaki, Maria; Vollmer, Günter

    2015-09-01

    Oleocanthal is a bioactive compound from olive oil. It has attracted considerable attention as it is anti-inflammatory, antiproliferative, and has been shown to possess neuroprotective properties in vitro and in vivo. Delineated from its polyphenolic structure, the aim of this study was to characterize oleocanthal towards estrogenic properties. This might contribute to partly explain the beneficial effects described for the Mediterranean diet. Estrogenic properties of oleocanthal were assessed by different methods: a) stimulation of reporter gene activity in MVLN or RNDA cells either expressing estrogen receptor α or β, b) stimulation of luciferase reporter gene activity in U2OS osteosarcoma cells expressing estrogen receptor α or β, and c) elucidation of the impact on estradiol-induced gene expression in U2OS cells transduced with both estrogen receptors. Depending on the cell line origin, oleocanthal inhibited luciferase activity (MVLN, U2OS-estrogen receptor β) or weakly induced reporter gene activity at 10 µM in U2OS-estrogen receptor α cells. However, oleocanthal inhibited stimulation of luciferase activity by estradiol from both estrogen receptors. Oleocanthal, if given alone, did not stimulate gene expression in U2OS cells, but it significantly modulated the response of estradiol. Oleocanthal enhanced the effect of estradiol on the regulation of those genes, which are believed to be regulated through heterodimeric estrogen receptors. As the estrogenic response pattern of oleocanthal is rather unique, we compared the results obtained with oleacein. Oleocanthal binds to both estrogen receptors inducing estradiol-agonistic or antiagonistic effects depending on the cell line. Regarding regulation of gene expression in U2OS-estrogen receptor α/β cells, oleocanthal and oleacein enhanced estradiol-mediated regulation of heterodimer-regulated genes. Georg Thieme Verlag KG Stuttgart · New York.

  20. The estrogen-related receptors (ERRs): potential targets against bone loss.

    Science.gov (United States)

    Zhang, Ling; Wong, Jiemin; Vanacker, Jean-Marc

    2016-10-01

    Bone loss and the resulting skeletal fragility is induced by several pathological or natural conditions, the most prominent of which being aging as well as the decreased levels of circulating estrogens in post-menopause females. To date, most treatments against bone loss aim at preventing excess bone resorption. We here summarize data indicating that the estrogen-related receptors (ERRs) α and γ prevent bone formation. Inhibiting these receptors may thus constitute an anabolic approach by increasing bone formation.

  1. Estrogen-mediated inactivation of FOXO3a by the G protein-coupled estrogen receptor GPER

    International Nuclear Information System (INIS)

    Zekas, Erin; Prossnitz, Eric R.

    2015-01-01

    Estrogen (17β-estradiol) promotes the survival and proliferation of breast cancer cells and its receptors represent important therapeutic targets. The cellular actions of estrogen are mediated by the nuclear estrogen receptors ERα and ERβ as well as the 7-transmembrane spanning G protein-coupled estrogen receptor (GPER). We previously reported that estrogen activates the phosphoinositide 3-kinase (PI3Kinase) pathway via GPER, resulting in phosphatidylinositol (3,4,5)-trisphosphate (PIP3) production within the nucleus of breast cancer cells; however, the mechanisms and consequences of this activity remained unclear. MCF7 breast cancer cells were transfected with GFP-fused Forkhead box O3 (FOXO3) as a reporter to assess localization in response to estrogen stimulation. Inhibitors of PI3Kinases and EGFR were employed to determine the mechanisms of estrogen-mediated FOXO3a inactivation. Receptor knockdown with siRNA and the selective GPER agonist G-1 elucidated the estrogen receptor(s) responsible for estrogen-mediated FOXO3a inactivation. The effects of selective estrogen receptor modulators and downregulators (SERMs and SERDs) on FOXO3a in MCF7 cells were also determined. Cell survival (inhibition of apoptosis) was assessed by caspase activation. In the estrogen-responsive breast cancer cell line MCF7, FOXO3a inactivation occurs on a rapid time scale as a result of GPER, but not ERα, stimulation by estrogen, established by the GPER-selective agonist G-1 and knockdown of GPER and ERα. GPER-mediated inactivation of FOXO3a is effected by the p110α catalytic subunit of PI3Kinase as a result of transactivation of the EGFR. The SERMs tamoxifen and raloxifene, as well as the SERD ICI182,780, were active in mediating FOXO3a inactivation in a GPER-dependent manner. Additionally, estrogen-and G-1-mediated stimulation of MCF7 cells results in a decrease in caspase activation under proapoptotic conditions. Our results suggest that non-genomic signaling by GPER contributes

  2. Novel estrogen receptor-related Transcripts in Marisa cornuarietis; a freshwater snail with reported sensitivity to estrogenic chemicals.

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    Bannister, Richard; Beresford, Nicola; May, Denise; Routledge, Edwin J; Jobling, Susan; Rand-Weaver, Mariann

    2007-04-01

    We have isolated novel molluskan steroid receptor transcripts orthologous to vertebrate estrogen receptors (ERs) and estrogen receptor-related receptors (ERRs) from the freshwater snail Marisa cornuarietis. Radiolabeled ligand binding analyses showed that neither recombinant receptor protein specifically bound 17beta-estradiol over the range applied (0.3-9.6 nM). These novel receptor transcripts have thus been designated mcER-like and mcERR respectively. Quantitative PCR revealed mcER-like to be expressed ubiquitously throughout a range of male and female structures studied, including neural and reproductive tissues. Highest absolute levels were seen in the male penis-sheath complex. The mcERR mRNA was also expressed ubiquitously throughout all male and female tissues analyzed here, with very low absolute transcript numbers in female accessory sex structures compared to other tissues.

  3. Sex Hormones and Cardiometabolic Health: Role of Estrogen and Estrogen Receptors.

    Science.gov (United States)

    Clegg, Deborah; Hevener, Andrea L; Moreau, Kerrie L; Morselli, Eugenia; Criollo, Alfredo; Van Pelt, Rachael E; Vieira-Potter, Victoria J

    2017-05-01

    With increased life expectancy, women will spend over three decades of life postmenopause. The menopausal transition increases susceptibility to metabolic diseases such as obesity, diabetes, cardiovascular disease, and cancer. Thus, it is more important than ever to develop effective hormonal treatment strategies to protect aging women. Understanding the role of estrogens, and their biological actions mediated by estrogen receptors (ERs), in the regulation of cardiometabolic health is of paramount importance to discover novel targeted therapeutics. In this brief review, we provide a detailed overview of the literature, from basic science findings to human clinical trial evidence, supporting a protective role of estrogens and their receptors, specifically ERα, in maintenance of cardiometabolic health. In so doing, we provide a concise mechanistic discussion of some of the major tissue-specific roles of estrogens signaling through ERα. Taken together, evidence suggests that targeted, perhaps receptor-specific, hormonal therapies can and should be used to optimize the health of women as they transition through menopause, while reducing the undesired complications that have limited the efficacy and use of traditional hormone replacement interventions. Copyright © 2017 Endocrine Society.

  4. Expression of estrogen and progesterone receptors in astrocytomas: a literature review

    Directory of Open Access Journals (Sweden)

    Cléciton Braga Tavares

    Full Text Available Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression.

  5. Expression of estrogen and progesterone receptors in astrocytomas: a literature review

    Science.gov (United States)

    Tavares, Cléciton Braga; Gomes-Braga, Francisca das Chagas Sheyla Almeida; Costa-Silva, Danylo Rafhael; Escórcio-Dourado, Carla Solange; Borges, Umbelina Soares; Conde, Airton Mendes; da Conceição Barros-Oliveira, Maria; Sousa, Emerson Brandão; da Rocha Barros, Lorena; Martins, Luana Mota; Facina, Gil; da-Silva, Benedito Borges

    2016-01-01

    Gliomas are the most common type of primary central nervous system neoplasm. Astrocytomas are the most prevalent type of glioma and these tumors may be influenced by sex steroid hormones. A literature review for the presence of estrogen and progesterone receptors in astrocytomas was conducted in the PubMed database using the following MeSH terms: “estrogen receptor beta” OR “estrogen receptor alpha” OR “estrogen receptor antagonists” OR “progesterone receptors” OR “astrocytoma” OR “glioma” OR “glioblastoma”. Among the 111 articles identified, 13 studies met our inclusion criteria. The majority of reports showed the presence of estrogen and progesterone receptors in astrocytomas. Overall, higher tumor grades were associated with decreased estrogen receptor expression and increased progesterone receptor expression. PMID:27626480

  6. Potential mechanisms underlying estrogen-induced expression of the molluscan estrogen receptor (ER) gene

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Thi Kim Anh [School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia); Department of Agriculture, Forestry and Fisheries, Vinh University, 182 Le Duan St., Vinh City, Nghe An (Viet Nam); MacFarlane, Geoff R. [School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia); Kong, Richard Yuen Chong [Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region (China); O’Connor, Wayne A. [New South Wales Department of Primary Industries, Port Stephens Fisheries Institute, Taylors Beach, NSW 2316 (Australia); Yu, Richard Man Kit, E-mail: Richard.Yu@newcastle.edu.au [School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308 (Australia)

    2016-10-15

    Highlights: • This is the first report on the putative promoter sequence of a molluscan ER gene. • The gene promoter contains putative binding sites for direct and indirect interaction with ER. • E2 upregulates ER gene expression in the ovary in vitro and in vivo. • E2-induced gene expression may require a novel ligand-dependent receptor. • The ER proximal promoter is hypomethylated regardless of gene expression levels. - Abstract: In vertebrates, estrogens and estrogen mimicking chemicals modulate gene expression mainly through a genomic pathway mediated by the estrogen receptors (ERs). Although the existence of an ER orthologue in the mollusc genome has been known for some time, its role in estrogen signalling has yet to be deciphered. This is largely due to its constitutive (ligand-independent) activation and a limited mechanistic understanding of its regulation. To fill this knowledge gap, we cloned and characterised an ER cDNA (sgER) and the 5′-flanking region of the gene from the Sydney rock oyster Saccostrea glomerata. The sgER cDNA is predicted to encode a 477-amino acid protein that contains a DNA-binding domain (DBD) and a ligand-binding domain (LBD) typically conserved among both vertebrate and invertebrate ERs. A comparison of the sgER LBD sequence with those of other ligand-dependent ERs revealed that the sgER LBD is variable at several conserved residues known to be critical for ligand binding and receptor activation. Ligand binding assays using fluorescent-labelled E2 and purified sgER protein confirmed that sgER is devoid of estrogen binding. In silico analysis of the sgER 5′-flanking sequence indicated the presence of three putative estrogen responsive element (ERE) half-sites and several putative sites for ER-interacting transcription factors, suggesting that the sgER promoter may be autoregulated by its own gene product. sgER mRNA is ubiquitously expressed in adult oyster tissues, with the highest expression found in the ovary

  7. Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

    Science.gov (United States)

    Khalil, Raouf A

    2013-12-15

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Expression of Estrogen and Progesterone Receptors among ...

    African Journals Online (AJOL)

    Study design: This is a descriptive study to detect the level of Estrogen (ER) and Progesterone (PR) receptors in a sample of biopsies from Sudanese women with breast cancer presented at Khartoum teaching Hospital Material and Methods: Forty biopsies from breast cancer patients were examined with immunostaining

  9. Characterization of estrogen receptors alpha and beta in uterine leiomyoma cells.

    Science.gov (United States)

    Valladares, Francisco; Frías, Ignacio; Báez, Delia; García, Candelaria; López, Francisco J; Fraser, James D; Rodríguez, Yurena; Reyes, Ricardo; Díaz-Flores, Lucio; Bello, Aixa R

    2006-12-01

    Cellular and subcellular localization of estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta) in uterine leiomyomas. Retrospective study. University of La Laguna (ULL) and Canary University Hospital (HUC). Premenopausal and postmenopausal women with uterine leiomyomas. Hysterectomy and myomectomy. Estrogen receptor alpha was only present in smooth muscle cells with variation in the subcellular location in different leiomyomas. Estrogen receptor beta was widely distributed in smooth muscle, endothelial, and connective tissue cells with nuclear location in all cases studied; variations were only found in the muscle cells for this receptor. Estrogens operate in leiomyoma smooth muscle cells through different receptors, alpha and beta. However they only act through the ERbeta in endothelial and connective cells.

  10. CITED2 modulates estrogen receptor transcriptional activity in breast cancer cells

    International Nuclear Information System (INIS)

    Lau, Wen Min; Doucet, Michele; Huang, David; Weber, Kristy L.; Kominsky, Scott L.

    2013-01-01

    Highlights: •The effects of elevated CITED2 on ER function in breast cancer cells are examined. •CITED2 enhances cell growth in the absence of estrogen and presence of tamoxifen. •CITED2 functions as a transcriptional co-activator of ER in breast cancer cells. -- Abstract: Cbp/p300-interacting transactivator with Glu/Asp-rich carboxy-terminal domain 2 (CITED2) is a member of the CITED family of non-DNA binding transcriptional co-activators of the p300/CBP-mediated transcription complex. Previously, we identified CITED2 as being overexpressed in human breast tumors relative to normal mammary epithelium. Upon further investigation within the estrogen receptor (ER)-positive subset of these breast tumor samples, we found that CITED2 mRNA expression was elevated in those associated with poor survival. In light of this observation, we investigated the effect of elevated CITED2 levels on ER function. While ectopic overexpression of CITED2 in three ER-positive breast cancer cell lines (MCF-7, T47D, and CAMA-1) did not alter cell proliferation in complete media, growth was markedly enhanced in the absence of exogenous estrogen. Correspondingly, cells overexpressing CITED2 demonstrated reduced sensitivity to the growth inhibitory effects of the selective estrogen receptor modulator, 4-hydroxytamoxifen. Subsequent studies revealed that basal ER transcriptional activity was elevated in CITED2-overexpressing cells and was further increased upon the addition of estrogen. Similarly, basal and estrogen-induced expression of the ER-regulated genes trefoil factor 1 (TFF1) and progesterone receptor (PGR) was higher in cells overexpressing CITED2. Concordant with this observation, ChIP analysis revealed higher basal levels of CITED2 localized to the TFF-1 and PGR promoters in cells with ectopic overexpression of CITED2, and these levels were elevated further in response to estrogen stimulation. Taken together, these data indicate that CITED2 functions as a transcriptional co

  11. Signaling cross-talk between peroxisome proliferator-activated receptor/retinoid X receptor and estrogen receptor through estrogen response elements.

    Science.gov (United States)

    Keller, H; Givel, F; Perroud, M; Wahli, W

    1995-07-01

    Peroxisome proliferator-activated receptors (PPARs) and retinoid X receptors (RXRs) are nuclear hormone receptors that are activated by fatty acids and 9-cis-retinoic acid, respectively. PPARs and RXRs form heterodimers that activate transcription by binding to PPAR response elements (PPREs) in the promoter of target genes. The PPREs described thus far consist of a direct tandem repeat of the AGGTCA core element with one intervening nucleotide. We show here that the vitellogenin A2 estrogen response element (ERE) can also function as a PPRE and is bound by a PPAR/RXR heterodimer. Although this heterodimer can bind to several other ERE-related palindromic response elements containing AGGTCA half-sites, only the ERE is able to confer transactivation of test reporter plasmids, when the ERE is placed either close to or at a distance from the transcription initiation site. Examination of natural ERE-containing promoters, including the pS2, very-low-density apolipoprotein II and vitellogenin A2 genes, revealed considerable differences in the binding of PPAR/RXR heterodimers to these EREs. In their natural promoter context, these EREs did not allow transcriptional activation by PPARs/RXRs. Analysis of this lack of stimulation of the vitellogenin A2 promoter demonstrated that PPARs/RXRs bind to the ERE but cannot transactivate due to a nonpermissive promoter structure. As a consequence, PPARs/RXRs inhibit transactivation by the estrogen receptor through competition for ERE binding. This is the first example of signaling cross-talk between PPAR/RXR and estrogen receptor.

  12. Hispolon inhibits the growth of estrogen receptor positive human breast cancer cells through modulation of estrogen receptor alpha

    International Nuclear Information System (INIS)

    Jang, Eun Hyang; Jang, Soon Young; Cho, In-Hye; Hong, Darong; Jung, Bom; Park, Min-Ju; Kim, Jong-Ho

    2015-01-01

    Human estrogen receptor α (ERα) is a nuclear transcription factor that is a major therapeutic target in breast cancer. The transcriptional activity of ERα is regulated by certain estrogen-receptor modulators. Hispolon, isolated from Phellinus linteus, a traditional medicinal mushroom called Sanghwang in Korea, has been used to treat various pathologies, such as inflammation, gastroenteric disorders, lymphatic diseases, and cancers. In this latter context, Hispolon has been reported to exhibit therapeutic efficacy against various cancer cells, including melanoma, leukemia, hepatocarcinoma, bladder cancer, and gastric cancer cells. However, ERα regulation by Hispolon has not been reported. In this study, we investigated the effects of Hispolon on the growth of breast cancer cells. We found that Hispolon decreased expression of ERα at both mRNA and the protein levels in MCF7 and T47D human breast cancer cells. Luciferase reporter assays showed that Hispolon decreased the transcriptional activity of ERα. Hispolon treatment also inhibited expression of the ERα target gene pS2. We propose that Hispolon, an anticancer drug extracted from natural sources, inhibits cell growth through modulation of ERα in estrogen-positive breast cancer cells and is a candidate for use in human breast cancer chemotherapy. - Highlights: • Hispolon decreased ERα expression at both mRNA and protein levels. • Hispolon decreased ERα transcriptional activity. • Hispolon treatment inhibited expression of ERα target gene pS2. • Shikonin is a candidate chemotherapeutic target in the treatment of human breast cancer

  13. Hispolon inhibits the growth of estrogen receptor positive human breast cancer cells through modulation of estrogen receptor alpha

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Eun Hyang; Jang, Soon Young; Cho, In-Hye [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Hong, Darong [Department of Life and Nanopharmaceutical Science, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Jung, Bom; Park, Min-Ju [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Kim, Jong-Ho, E-mail: jonghokim@khu.ac.kr [Department of Pharmacy, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of)

    2015-08-07

    Human estrogen receptor α (ERα) is a nuclear transcription factor that is a major therapeutic target in breast cancer. The transcriptional activity of ERα is regulated by certain estrogen-receptor modulators. Hispolon, isolated from Phellinus linteus, a traditional medicinal mushroom called Sanghwang in Korea, has been used to treat various pathologies, such as inflammation, gastroenteric disorders, lymphatic diseases, and cancers. In this latter context, Hispolon has been reported to exhibit therapeutic efficacy against various cancer cells, including melanoma, leukemia, hepatocarcinoma, bladder cancer, and gastric cancer cells. However, ERα regulation by Hispolon has not been reported. In this study, we investigated the effects of Hispolon on the growth of breast cancer cells. We found that Hispolon decreased expression of ERα at both mRNA and the protein levels in MCF7 and T47D human breast cancer cells. Luciferase reporter assays showed that Hispolon decreased the transcriptional activity of ERα. Hispolon treatment also inhibited expression of the ERα target gene pS2. We propose that Hispolon, an anticancer drug extracted from natural sources, inhibits cell growth through modulation of ERα in estrogen-positive breast cancer cells and is a candidate for use in human breast cancer chemotherapy. - Highlights: • Hispolon decreased ERα expression at both mRNA and protein levels. • Hispolon decreased ERα transcriptional activity. • Hispolon treatment inhibited expression of ERα target gene pS2. • Shikonin is a candidate chemotherapeutic target in the treatment of human breast cancer.

  14. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

    Science.gov (United States)

    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERRα-dependent manner. XCT790 induces, in a p53-independent manner, the expression of the cell cycle inhibitor p21waf/cip1 at the protein, mRNA, and promoter level, leading to an accumulation of hypophosphorylated Rb. Finally, XCT790 reduces cell tumorigenicity in Nude mice. PMID:19546226

  15. Genistein modulates the estrogen receptor and suppresses angiogenesis and inflammation in the murine model of peritoneal endometriosis

    Directory of Open Access Journals (Sweden)

    Sutrisno Sutrisno

    2018-04-01

    Full Text Available The purpose of this study was to investigate the effect of genistein administration on the modulation of the estrogen receptor, inhibition of inflammation and angiogenesis in the murine model of peritoneal endometriosis. A total of thirty-six mice (Mus musculus were divided into six groups (n = 6, including the control group, endometriosis group, endometriosis group treated with various doses of genistein (0.78; 1.04; 1.3 mg/day, and endometriosis group treated with leuprolide acetate (0.00975 mg/day every 5 days for 15 days. Analysis of estrogen receptor-α, estrogen receptor-β, TNF-α, IL-6, VEGF, and HIF-1α were performed immunohistochemically. Expression of estrogen receptor-α, estrogen receptor-β, TNF-α, IL-6, VEGF and HIF-1α increased significantly compared with the control group (p  0.05. Genistein also decreased the expression of TNF-α and IL-6 (1.04 and 1.3 mg/day compared with the endometriosis group, reaching level comparable to that of the control group (p > 0.05. It was concluded that genistein is able to modulate estrogen receptor-α and estrogen receptor-β and inhibit the development of inflammation and angiogenesis in the murine model of peritoneal endometriosis. Thus, genistein can be a candidate in the treatment of endometriosis. Keywords: Estrogen receptor, Growth factor, Inflammation, Angiogenesis, Peritoneum

  16. The Determinations of Estrogen and Progesterone Receptor in Breast Cancer Cell by Radioimmunoassay Method

    International Nuclear Information System (INIS)

    Kim, Chi Yeul

    1981-01-01

    The estrogen and progesterone receptors which are bound to the cytoplasmic protein of cancer cells were measured in 20 patients with the early breast cancer by means of radioimmunoassay using charcoal. 1) The patients with estrogen receptor positive were 13 (65%) of 20 cases and with progestrone receptor positive were 7 cases (35%) in the early breast cancer. 2) Coexistence of estrogen and progesterone receptor positive was noted in 7 cases (35%). The cases of estrogen receptor positive and progesterone receptor negative were 6 cases (33.3%), while there were no cases of estrogen receptor negative with progesterone receptor positive. 3) Coincidence of estrogen and progesterone negative was noticed in 7 cases (35%). Conclusively it is considered that the measurement of estrogen and progesterone receptors has relevance as predictive value, in the response to hormonal manipulations and chemotherapy for breast cancer patients.

  17. Nonsteroidal Selective Androgen Receptor Modulators and Selective Estrogen Receptor β Agonists Moderate Cognitive Deficits and Amyloid-β Levels in a Mouse Model of Alzheimer’s Disease

    Science.gov (United States)

    2013-01-01

    Decreases of the sex steroids, testosterone and estrogen, are associated with increased risk of Alzheimer’s disease. Testosterone and estrogen supplementation improves cognitive deficits in animal models of Alzheimer’s disease. Sex hormones play a role in the regulation of amyloid-β via induction of the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme. To mimic the effect of dihydrotestosterone (DHT), we administered a selective androgen receptor agonist, ACP-105, alone and in combination with the selective estrogen receptor β (ERβ) agonist AC-186 to male gonadectomized triple transgenic mice. We assessed long-term spatial memory in the Morris water maze, spontaneous locomotion, and anxiety-like behavior in the open field and in the elevated plus maze. We found that ACP-105 given alone decreases anxiety-like behavior. Furthermore, when ACP-105 is administered in combination with AC-186, they increase the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme and decrease amyloid-β levels in the brain as well as improve cognition. Interestingly, the androgen receptor level in the brain was increased by chronic treatment with the same combination treatment, ACP-105 and AC-186, not seen with DHT or ACP-105 alone. Based on these results, the beneficial effect of the selective ERβ agonist as a potential therapeutic for Alzheimer’s disease warrants further investigation. PMID:24020966

  18. Combinations of physiologic estrogens with xenoestrogens alter calcium and kinase responses, prolactin release, and membrane estrogen receptor trafficking in rat pituitary cells

    Directory of Open Access Journals (Sweden)

    Watson Cheryl S

    2010-10-01

    Full Text Available Abstract Background Xenoestrogens such as alkylphenols and the structurally related plastic byproduct bisphenol A have recently been shown to act potently via nongenomic signaling pathways and the membrane version of estrogen receptor-α. Though the responses to these compounds are typically measured individually, they usually contaminate organisms that already have endogenous estrogens present. Therefore, we used quantitative medium-throughput screening assays to measure the effects of physiologic estrogens in combination with these xenoestrogens. Methods We studied the effects of low concentrations of endogenous estrogens (estradiol, estriol, and estrone at 10 pM (representing pre-development levels, and 1 nM (representing higher cycle-dependent and pregnancy levels in combinations with the same levels of xenoestrogens in GH3/B6/F10 pituitary cells. These levels of xenoestrogens represent extremely low contamination levels. We monitored calcium entry into cells using Fura-2 fluorescence imaging of single cells. Prolactin release was measured by radio-immunoassay. Extracellular-regulated kinase (1 and 2 phospho-activations and the levels of three estrogen receptors in the cell membrane (ERα, ERβ, and GPER were measured using a quantitative plate immunoassay of fixed cells either permeabilized or nonpermeabilized (respectively. Results All xenoestrogens caused responses at these concentrations, and had disruptive effects on the actions of physiologic estrogens. Xenoestrogens reduced the % of cells that responded to estradiol via calcium channel opening. They also inhibited the activation (phosphorylation of extracellular-regulated kinases at some concentrations. They either inhibited or enhanced rapid prolactin release, depending upon concentration. These latter two dose-responses were nonmonotonic, a characteristic of nongenomic estrogenic responses. Conclusions Responses mediated by endogenous estrogens representing different life stages are

  19. Clinical and Genomic Crosstalk between Glucocorticoid Receptor and Estrogen Receptor α In Endometrial Cancer

    Directory of Open Access Journals (Sweden)

    Jeffery M. Vahrenkamp

    2018-03-01

    Full Text Available Summary: Steroid hormone receptors are simultaneously active in many tissues and are capable of altering each other’s function. Estrogen receptor α (ER and glucocorticoid receptor (GR are expressed in the uterus, and their ligands have opposing effects on uterine growth. In endometrial tumors with high ER expression, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic-binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is altered significantly by estradiol with GR recruited to ER-bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol but with additional regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer. : Estrogen receptor α (ER and glucocorticoid receptor (GR are expressed in the uterus and have differential effects on growth. Vahrenkamp et al. find that expression of both receptors is associated with poor outcome in endometrial cancer and that simultaneous induction of ER and GR leads to molecular interplay between the receptors. Keywords: estrogen receptor, glucocorticoid receptor, endometrial cancer

  20. Estrogen promotes megakaryocyte polyploidization via estrogen receptor beta-mediated transcription of GATA1.

    Science.gov (United States)

    Du, C; Xu, Y; Yang, K; Chen, S; Wang, X; Wang, S; Wang, C; Shen, M; Chen, F; Chen, M; Zeng, D; Li, F; Wang, T; Wang, F; Zhao, J; Ai, G; Cheng, T; Su, Y; Wang, J

    2017-04-01

    Estrogen is reported to be involved in thrombopoiesis and the disruption of its signaling may cause myeloproliferative disease, yet the underlying mechanisms remain largely unknown. GATA-binding factor 1 (GATA1) is a key regulator of megakaryocyte (MK) differentiation and its deficiency will lead to megakaryoblastic leukemia. Here we show that estrogen can dose-dependently promote MK polyploidization and maturation via activation of estrogen receptor beta (ERβ), accompanied by a significant upregulation of GATA1. Chromatin immunoprecipitation and a dual luciferase assay demonstrate that ERβ can directly bind the promoter region of GATA1 and activate its transcription. Steroid receptor coactivator 3 (SRC3) is involved in ERβ-mediated GATA1 transcription. The deficiency of ERβ or SRC3, similar to the inhibition of GATA1, leads to the impediment of estrogen-induced MK polyploidization and platelet production. Further investigations reveal that signal transducer and activator of transcription 1 signaling pathway downstream of GATA1 has a crucial role in estrogen-induced MK polyploidization, and ERβ-mediated GATA1 upregulation subsequently enhances nuclear factor erythroid-derived 2 expression, thereby promoting proplatelet formation and platelet release. Our study provides a deep insight into the molecular mechanisms of estrogen signaling in regulating thrombopoiesis and the pathogenesis of ER deficiency-related leukemia.

  1. Role of estrogen in lung cancer based on the estrogen receptor-epithelial mesenchymal transduction signaling pathways

    Directory of Open Access Journals (Sweden)

    Zhao XZ

    2015-10-01

    Full Text Available Xiao-zhen Zhao,1,* Yu Liu,1,* Li-juan Zhou,1,* Zhong-qi Wang,1 Zhong-hua Wu,2 Xiao-yuan Yang31Department of Tumor, Longhua Hospital, 2Center of Science and Technology, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China; 3Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA*These authors contributed equally to this workBackground/aim: Estrogen is reported to promote the occurrence and development of several human cancers. Increasing evidence shows that most human lung tumors exert estrogen receptor expression. In the present study, we investigated the underlying mechanism of estrogen effect in lung cancer through estrogen receptor-epithelial–mesechymal-transition signaling pathways for the first time.Materials and methods: A total of 36 inbred C57BL/6 mice (18 male and 18 female were injected subcutaneously with human lung adenocarcinoma cell line, Lewis. After the lung tumor model was established, mice with lung adenocarcinoma were randomly divided into three groups for each sex (n=6, such as vehicle group, estrogen group, and estrogen plus tamoxifen group. The six groups of mice were sacrificed after 21 days of drug treatment. Tumor tissue was stripped and weighed, and tumor inhibition rate was calculated based on average tumor weight. Protein and messenger RNA (mRNA expressions of estrogen receptor α (ERα, estrogen receptor β (ERβ, phosphatidylinositol 3'-kinase (PI3K, AKT, E-cadherin, and vimentin were detected in both tumor tissue and lung tissue by using immunohistochemistry and real-time reverse transcription-polymerase chain reaction.Results: 1 For male mice: in the estrogen group, estrogen treatment significantly increased ERα protein and mRNA expressions in tumor tissue and protein expression of PI3K, AKT, and vimentin in both tumor tissue and lung tissue compared with the vehicle-treated group. Besides, m

  2. Novel drugs that target the estrogen-related receptor alpha: their therapeutic potential in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    May, Felicity EB, E-mail: F.E.B.May@ncl.ac.uk [Northern Institute for Cancer Research and Department of Pathology, Faculty of Medical Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne (United Kingdom)

    2014-05-23

    The incidence of breast cancer continues to rise: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel

  3. Novel drugs that target the estrogen-related receptor alpha: their therapeutic potential in breast cancer

    International Nuclear Information System (INIS)

    May, Felicity EB

    2014-01-01

    The incidence of breast cancer continues to rise: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel

  4. Association of estrogen receptor beta variants and serum levels of estradiol with risk of colorectal cancer: a case control study

    Directory of Open Access Journals (Sweden)

    Wu Huanlei

    2012-07-01

    Full Text Available Abstract Background Endogenous estrogens may play a vital role in colorectal tumorigenesis. Estrogen receptor beta is the predominant subtype which mediates the biological effect of estrogens, while loss of expression of estrogen receptor beta has been indicated as a common step in the development of colorectal cancer (CRC. Epidemiological studies have revealed several functional polymorphisms of estrogen receptor beta (ESR2 for cancer risk, but relevant study in CRC is limited, particularly in men. This study aimed to investigate the association of circulating estradiol and variations of ESR2 with CRC risk in men. Methods We initiated a case–control study consisting of 390 patients with CRC and 445 healthy controls in men only. We genotyped ESR2 single nucleotide polymorphisms (SNPs rs1256049 and rs4986938 and measured serum estradiol concentration using chemilluminescence immunoassay. Multivariable logistic regression model was performed to evaluate the associations between these variables and CRC risk. Results ESR2 rs1256049 CT/TT genotypes were associated with reduced risk of CRC (odds ratio [OR], 0.7, 95% confidence interval [CI], 0.5–1.0, while rs4986938 CT/TT genotypes were associated with increased risk of CRC (OR, 1.5, 95% CI, 1.0–2.1. In addition, the CRC risk increased with the number of risk genotypes of these two SNPs in a dose–response manner (Ptrend, 0.003. Specifically, subjects carrying risk genotypes of both SNPs had the highest risk of CRC (OR, 2.0, 95% CI, 1.3–3.3.. Moreover, serum estradiol concentration alone was associated with risk of CRC in men (OR, 1.2, 95% CI, 1.0–1.3. However, individuals presenting both rs4986938 CT/TT genotypes and high level of serum estradiol had a high risk of CRC (OR, 2.3, 95% CI, 1.4–3.9, compared with those presenting CC genotype and low level of serum estradiol. The similar joint results were not observed for SNP rs1256049. Conclusions These results suggest that endogenous

  5. Estrogen binding, receptor mRNA, and biologic response in osteoblast-like osteosarcoma cells

    International Nuclear Information System (INIS)

    Komm, B.S.; Terpening, C.M.; Benz, D.J.; Graeme, K.A.; Gallegos, A.; Korc, M.; Greene, G.L.; O'Malley, B.W.; Haussler, M.R.

    1988-01-01

    High specific activity estradiol labeled with iodine-125 was used to detect approximately 200 saturable, high-affinity (dissociation constant approximately equal to 1.0 nM) nuclear binding sites in rat (ROS 17/2.8) and human (HOS TE85) clonal osteoblast-like osteosarcoma cells. Of the steroids tested, only testosterone exhibited significant cross-reactivity with estrogen binding. RNA blot analysis with a complementary DNA probe to the human estrogen receptor revealed putative receptor transcripts of 6 to 6.2 kilobases in both rat and human osteosarcoma cells. Type I procollagen and transforming growth factor-beta messenger RNA levels were enhanced in cultured human osteoblast-like cells treated with 1 nM estradiol. Thus, estrogen can act directly on osteoblasts by a receptor-mediated mechanism and thereby modulate the extracellular matrix and other proteins involved in the maintenance of skeletal mineralization and remodeling

  6. A-C Estrogens as Potent and Selective Estrogen Receptor-Beta Agonists (SERBAs) to Enhance Memory Consolidation under Low-Estrogen Conditions.

    Science.gov (United States)

    Hanson, Alicia M; Perera, K L Iresha Sampathi; Kim, Jaekyoon; Pandey, Rajesh K; Sweeney, Noreena; Lu, Xingyun; Imhoff, Andrea; Mackinnon, Alexander Craig; Wargolet, Adam J; Van Hart, Rochelle M; Frick, Karyn M; Donaldson, William A; Sem, Daniel S

    2018-06-04

    Estrogen receptor-beta (ERβ) is a drug target for memory consolidation in postmenopausal women. Herein is reported a series of potent and selective ERβ agonists (SERBAs) with in vivo efficacy that are A-C estrogens, lacking the B and D estrogen rings. The most potent and selective A-C estrogen is selective for activating ER relative to seven other nuclear hormone receptors, with a surprising 750-fold selectivity for the β over α isoform and with EC 50 s of 20-30 nM in cell-based and direct binding assays. Comparison of potency in different assays suggests that the ER isoform selectivity is related to the compound's ability to drive the productive conformational change needed to activate transcription. The compound also shows in vivo efficacy after microinfusion into the dorsal hippocampus and after intraperitoneal injection (0.5 mg/kg) or oral gavage (0.5 mg/kg). This simple yet novel A-C estrogen is selective, brain penetrant, and facilitates memory consolidation.

  7. Designer interface peptide grafts target estrogen receptor alpha dimerization

    International Nuclear Information System (INIS)

    Chakraborty, S.; Asare, B.K.; Biswas, P.K.; Rajnarayanan, R.V.

    2016-01-01

    The nuclear transcription factor estrogen receptor alpha (ERα), triggered by its cognate ligand estrogen, regulates a variety of cellular signaling events. ERα is expressed in 70% of breast cancers and is a widely validated target for anti-breast cancer drug discovery. Administration of anti-estrogen to block estrogen receptor activation is still a viable anti-breast cancer treatment option but anti-estrogen resistance has been a significant bottle-neck. Dimerization of estrogen receptor is required for ER activation. Blocking ERα dimerization is therefore a complementary and alternative strategy to combat anti-estrogen resistance. Dimer interface peptide “I-box” derived from ER residues 503–518 specifically blocks ER dimerization. Recently using a comprehensive molecular simulation we studied the interaction dynamics of ERα LBDs in a homo-dimer. Based on this study, we identified three interface recognition peptide motifs LDKITDT (ERα residues 479–485), LQQQHQRLAQ (residues 497–506), and LSHIRHMSNK (residues 511–520) and reported the suitability of using LQQQHQRLAQ (ER 497–506) as a template to design inhibitors of ERα dimerization. Stability and self-aggregation of peptide based therapeutics poses a significant bottle-neck to proceed further. In this study utilizing peptide grafted to preserve their pharmacophoric recognition motif and assessed their stability and potential to block ERα mediated activity in silico and in vitro. The Grafted peptides blocked ERα mediated cell proliferation and viability of breast cancer cells but did not alter their apoptotic fate. We believe the structural clues identified in this study can be used to identify novel peptidometics and small molecules that specifically target ER dimer interface generating a new breed of anti-cancer agents. - Highlights: • Designer peptide grafts retain core molecular recognition motif during MD simulations. • Designer peptide grafts with Poly-ALA helix form stable

  8. Designer interface peptide grafts target estrogen receptor alpha dimerization

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, S. [Laboratory of Computational Biophysics & Bioengineering, Department of Physics, Tougaloo College, Tougaloo, MS 39174 (United States); Asare, B.K. [Department of Pharmacology and Toxicology, University of Buffalo, Buffalo, NY 14214 (United States); Biswas, P.K., E-mail: pbiswas@tougaloo.edu [Laboratory of Computational Biophysics & Bioengineering, Department of Physics, Tougaloo College, Tougaloo, MS 39174 (United States); Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu [Department of Pharmacology and Toxicology, University of Buffalo, Buffalo, NY 14214 (United States)

    2016-09-09

    The nuclear transcription factor estrogen receptor alpha (ERα), triggered by its cognate ligand estrogen, regulates a variety of cellular signaling events. ERα is expressed in 70% of breast cancers and is a widely validated target for anti-breast cancer drug discovery. Administration of anti-estrogen to block estrogen receptor activation is still a viable anti-breast cancer treatment option but anti-estrogen resistance has been a significant bottle-neck. Dimerization of estrogen receptor is required for ER activation. Blocking ERα dimerization is therefore a complementary and alternative strategy to combat anti-estrogen resistance. Dimer interface peptide “I-box” derived from ER residues 503–518 specifically blocks ER dimerization. Recently using a comprehensive molecular simulation we studied the interaction dynamics of ERα LBDs in a homo-dimer. Based on this study, we identified three interface recognition peptide motifs LDKITDT (ERα residues 479–485), LQQQHQRLAQ (residues 497–506), and LSHIRHMSNK (residues 511–520) and reported the suitability of using LQQQHQRLAQ (ER 497–506) as a template to design inhibitors of ERα dimerization. Stability and self-aggregation of peptide based therapeutics poses a significant bottle-neck to proceed further. In this study utilizing peptide grafted to preserve their pharmacophoric recognition motif and assessed their stability and potential to block ERα mediated activity in silico and in vitro. The Grafted peptides blocked ERα mediated cell proliferation and viability of breast cancer cells but did not alter their apoptotic fate. We believe the structural clues identified in this study can be used to identify novel peptidometics and small molecules that specifically target ER dimer interface generating a new breed of anti-cancer agents. - Highlights: • Designer peptide grafts retain core molecular recognition motif during MD simulations. • Designer peptide grafts with Poly-ALA helix form stable

  9. Role of estrogen receptor-α on food demand elasticity.

    Science.gov (United States)

    Minervini, Vanessa; Rowland, Neil E; Robertson, Kimberly L; Foster, Thomas C

    2015-05-01

    Estrogens have been shown to have an inhibitory effect on food intake under free-feeding conditions, yet the effects of estrogens on food-maintained operant responding have been studied to a much lesser extent and, thus, are not well understood. Therefore, the purpose of the present experiment was to use a behavioral economics paradigm to assess differences in demand elasticity between mice with knockout of the estrogen receptor subtype α, knockout of subtype β, and their wild type controls. The mice responded in a closed economy, and the price of food was increased by increasing the fixed-ratio response requirement every four sessions. Overall, we found that mice with the knockout of receptor subtype α had the most elastic demand functions. Therefore, under these conditions, estrogens increased food seeking via activation of the receptor subtype α. The results were inconsistent with those reported by previous studies that employed free-feeding conditions. © Society for the Experimental Analysis of Behavior.

  10. Estrogen enhances mismatch repair by induction of MLH1 expression via estrogen receptor-β.

    Science.gov (United States)

    Lu, Jun-Yu; Jin, Peng; Gao, Wei; Wang, De-Zhi; Sheng, Jian-Qiu

    2017-06-13

    Epidemiological data demonstrated that hormone replace treatment has protective effect against colorectal cancer (CRC). Our previous studies showed that this effect may be associated with DNA mismatch repair. This study aims to investigate the mechanism of estrogen induction of MLH1, and whether colorectal tumor proliferation can be inhibited through induction of MLH1 by estrogen signal pathway. Human CRC cell lines were used to examine the regulation of MLH1 expression by over-expression and depletion of estrogen receptor-α (ERα) and estrogen receptor-β (ERβ), under the treatment with 17β-estradiol or β-Estradiol 6-(O-carboxy-methyl)oxime:BSA, followed by a real-time Q-PCR and Western blotting analysis. Luciferase reporter and chromatin immunoprecipitation assays were used to identify the estrogen response elements in the proximal promoter of MLH1 gene. Then, the influence of estrogen-induced MLH1 on CRC tumor growth were determined in vitro and in vivo. We found that mismatch repair ability and microsatellite stability of cells were enhanced by estrogen via induction of MLH1 expression, which was mediated by ERβ, through a transcriptional activation process. Furthermore, we identified that ERβ exerted an inhibitory effect on CRC tumor proliferation in vitro and in vivo, combined with 5-FU, through up-regulation of MLH1 expression. Finally, we concluded that estrogen enhances mismatch repair ability and tumor inhibition effect in vitro and in vivo, via induction of MLH1 expression mediated by ERβ.

  11. Sex differences in opioid analgesia and addiction: interactions among opioid receptors and estrogen receptors

    Science.gov (United States)

    2013-01-01

    Opioids are widely used as the pain reliever and also notorious for being addictive drugs. Sex differences in the opioid analgesia and addiction have been reported and investigated in human subjects and animal models. Yet, the molecular mechanism underlying the differences between males and females is still unclear. Here, we reviewed the literature describing the sex differences in analgesic responses and addiction liabilities to clinically relevant opioids. The reported interactions among opioids, estrogens, opioid receptors, and estrogen receptors are also evaluated. We postulate that the sex differences partly originated from the crosstalk among the estrogen and opioid receptors when stimulated by the exogenous opioids, possibly through common secondary messengers and the downstream gene transcriptional regulators. PMID:24010861

  12. Mechanisms of G Protein-Coupled Estrogen Receptor-Mediated Spinal Nociception

    DEFF Research Database (Denmark)

    Deliu, Elena; Brailoiu, G. Cristina; Arterburn, Jeffrey B.

    2012-01-01

    . Cytosolic calcium concentration elevates faster and with higher amplitude following G-1 intracellular microinjections compared to extracellular exposure, suggesting subcellular GPER functionality. Thus, GPER activation results in spinal nociception, and the downstream mechanisms involve cytosolic calcium......Human and animal studies suggest that estrogens are involved in the processing of nociceptive sensory information and analgesic responses in the central nervous system. Rapid pronociceptive estrogenic effects have been reported, some of which likely involve G protein-coupled estrogen receptor (GPER......) activation. Membrane depolarization and increases in cytosolic calcium and reactive oxygen species (ROS) levels are markers of neuronal activation, underlying pain sensitization in the spinal cord. Using behavioral, electrophysiological, and fluorescent imaging studies, we evaluated GPER involvement...

  13. Computational estimation of rainbow trout estrogen receptor binding affinities for environmental estrogens

    International Nuclear Information System (INIS)

    Shyu, Conrad; Cavileer, Timothy D.; Nagler, James J.; Ytreberg, F. Marty

    2011-01-01

    Environmental estrogens have been the subject of intense research due to their documented detrimental effects on the health of fish and wildlife and their potential to negatively impact humans. A complete understanding of how these compounds affect health is complicated because environmental estrogens are a structurally heterogeneous group of compounds. In this work, computational molecular dynamics simulations were utilized to predict the binding affinity of different compounds using rainbow trout (Oncorhynchus mykiss) estrogen receptors (ERs) as a model. Specifically, this study presents a comparison of the binding affinity of the natural ligand estradiol-17β to the four rainbow trout ER isoforms with that of three known environmental estrogens 17α-ethinylestradiol, bisphenol A, and raloxifene. Two additional compounds, atrazine and testosterone, that are known to be very weak or non-binders to ERs were tested. The binding affinity of these compounds to the human ERα subtype is also included for comparison. The results of this study suggest that, when compared to estradiol-17β, bisphenol A binds less strongly to all four receptors, 17α-ethinylestradiol binds more strongly, and raloxifene has a high affinity for the α subtype only. The results also show that atrazine and testosterone are weak or non-binders to the ERs. All of the results are in excellent qualitative agreement with the known in vivo estrogenicity of these compounds in the rainbow trout and other fishes. Computational estimation of binding affinities could be a valuable tool for predicting the impact of environmental estrogens in fish and other animals.

  14. Classical and Nonclassical Estrogen Receptor Action on Chromatin Templates

    National Research Council Canada - National Science Library

    Nordeen, Steven

    2000-01-01

    .... Using newly-developed approaches, I investigated mechanisms of estrogen/estrogen receptor action on chromatin templates in vitro in order to better understand the role of chromatin in steroid-regulated gene expression...

  15. Classical and Nonclassical Estrogen Receptor Action on Chromatin Templaces

    National Research Council Canada - National Science Library

    Nordeen, Steve

    2001-01-01

    .... Using newly-developed approaches, I investigated mechanisms of estrogen/estrogen receptor action on chromatin templates in vitro in order to better understand the role of chromatin in steroid-regulated gene expression...

  16. Estrogen and estrogen receptor alpha promotes malignancy and osteoblastic tumorigenesis in prostate cancer.

    Science.gov (United States)

    Mishra, Sweta; Tai, Qin; Gu, Xiang; Schmitz, James; Poullard, Ashley; Fajardo, Roberto J; Mahalingam, Devalingam; Chen, Xiaodong; Zhu, Xueqiong; Sun, Lu-Zhe

    2015-12-29

    The role of estrogen signaling in regulating prostate tumorigenesis is relatively underexplored. Although, an increasing body of evidence has linked estrogen receptor beta (ERß) to prostate cancer, the function of estrogen receptor alpha (ERα) in prostate cancer is not very well studied. We have discovered a novel role of ERα in the pathogenesis of prostate tumors. Here, we show that prostate cancer cells express ERα and estrogen induces oncogenic properties in prostate cancer cells through ERα. Importantly, ERα knockdown in the human prostate cancer PacMetUT1 cells as well as pharmacological inhibition of ERα with ICI 182,780 inhibited osteoblastic lesion formation and lung metastasis in vivo. Co-culture of pre-osteoblasts with cancer cells showed a significant induction of osteogenic markers in the pre-osteoblasts, which was attenuated by knockdown of ERα in cancer cells suggesting that estrogen/ERα signaling promotes crosstalk between cancer and osteoblastic progenitors to stimulate osteoblastic tumorigenesis. These results suggest that ERα expression in prostate cancer cells is essential for osteoblastic lesion formation and lung metastasis. Thus, inhibition of ERα signaling in prostate cancer cells may be a novel therapeutic strategy to inhibit the osteoblastic lesion development as well as lung metastasis in patients with advanced prostate cancer.

  17. Tamoxifen induces the expression of maspin through estrogen receptor-alpha.

    Science.gov (United States)

    Liu, Zesheng; Shi, Heidi Y; Nawaz, Zafar; Zhang, Ming

    2004-06-08

    Maspin (mammary serine protease inhibitor) is a tumor suppressor gene that plays an important role in inhibiting tumor growth, invasion and metastasis. Maspin expression is down regulated at transcription level in primary and metastatic breast tumor cells. Previous studies on hormonal regulation of maspin prompt us to test whether an estrogen antagonist tamoxifen (TAM) can exert its anti-tumor function by up regulating maspin gene expression. For this purpose, we first tested whether maspin promoter could be activated in normal and several breast tumor cells. We then carried out a series of promoter analysis in which estrogen receptors and TAM were reconstituted in an in vitro cell culture system. Here we report our new finding that tumor suppresser gene maspin is one of the TAM target genes. TAM induces a maspin/luciferase reporter in cell culture and this induction requires the presence of (estrogen receptor alpha) ERalpha but not estrogen receptor-beta (ERbeta). Maspin promoter deletion and mutation analysis showed that the cis element(s) within a region between -90and+87 bp but not the HRE site (-272 bp) was involved in TAM induction of maspin expression. TAM bound ERalpha may directly control maspin gene expression through the interaction with cofactor (s). Analysis using several ERalpha mutants showed that the N-terminal A/B motif (AF-1) was critical for maspin basal level transcription activation. An ERalpha mutant with point mutations at DNA binding domain abolished estrogen induction of an ERE-luciferase reporter but was still active in activating maspin promoter by TAM. LBD-AF2 domain was required for ERalpha-dependent TAM induction. Deletion of LBD-AF2 or a point mutation in the ERalpha LBD-AF2 region (LBDmtL539A) completely abolished the activation of maspin promoter, suggesting that TAM induction of maspin involves the recruitment of cofactor(s) by ERalpha to the maspin promoter region. This finding indicates that one of the pathways for cancer

  18. DNA Repair, Redox Regulation and Modulation of Estrogen Receptor Alpha Mediated Transcription

    Science.gov (United States)

    Curtis-Ducey, Carol Dianne

    2009-01-01

    Interaction of estrogen receptor [alpha] (ER[alpha]) with 17[beta]-estradiol (E[subscript 2]) facilitates binding of the receptor to estrogen response elements (EREs) in target genes, which in turn leads to recruitment of coregulatory proteins. To better understand how estrogen-responsive genes are regulated, our laboratory identified a number of…

  19. [Roles of G protein-coupled estrogen receptor in the male reproductive system].

    Science.gov (United States)

    Chen, Kai-hong; Zhang, Xian; Jiang, Xue-wu

    2016-02-01

    The G protein-coupled estrogen receptor (GPER), also known as G protein-coupled receptor 30 (GPR30), was identified in the recent years as a functional membrane receptor different from the classical nuclear estrogen receptors. This receptor is widely expressed in the cortex, cerebellum, hippocampus, heart, lung, liver, skeletal muscle, and the urogenital system. It is responsible for the mediation of nongenomic effects associated with estrogen and its derivatives, participating in the physiological activities of the body. The present study reviews the molecular structure, subcellular localization, signaling pathways, distribution, and function of GPER in the male reproductive system.

  20. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

    OpenAIRE

    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERR...

  1. Expression and functional roles of G-protein-coupled estrogen receptor (GPER) in human eosinophils.

    Science.gov (United States)

    Tamaki, Mami; Konno, Yasunori; Kobayashi, Yoshiki; Takeda, Masahide; Itoga, Masamichi; Moritoki, Yuki; Oyamada, Hajime; Kayaba, Hiroyuki; Chihara, Junichi; Ueki, Shigeharu

    2014-07-01

    Sexual dimorphism in asthma links the estrogen and allergic immune responses. The function of estrogen was classically believed to be mediated through its nuclear receptors, i.e., estrogen receptors (ERs). However, recent studies established the important roles of G-protein-coupled estrogen receptor (GPER/GPR30) as a novel membrane receptor for estrogen. To date, the role of GPER in allergic inflammation is poorly understood. The purpose of this study was to examine whether GPER might affect the functions of eosinophils, which play an important role in the pathogenesis of asthma. Here, we demonstrated that GPER was expressed in purified human peripheral blood eosinophils both at the mRNA and protein levels. Although GPER agonist G-1 did not induce eosinophil chemotaxis or chemokinesis, preincubation with G-1 enhanced eotaxin (CCL11)-directed eosinophil chemotaxis. G-1 inhibited eosinophil spontaneous apoptosis and caspase-3 activities. The anti-apoptotic effect was not affected by the cAMP-phospodiesterase inhibitor rolipram or phosphoinositide 3-kinase inhibitors. In contrast to resting eosinophils, G-1 induced apoptosis and increased caspase-3 activities when eosinophils were co-stimulated with IL-5. No effect of G-1 was observed on eosinophil degranulation in terms of release of eosinophil-derived neurotoxin (EDN). The current study indicates the functional capacities of GPER on human eosinophils and also provides the previously unrecognized mechanisms of interaction between estrogen and allergic inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ERα and ERβ2 and are functionally modulated by estrogens.

    Science.gov (United States)

    Iwanowicz, Luke R; Stafford, James L; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W; Blazer, Vicki S

    2014-09-01

    Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ERα and ERβ2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ERβ2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17β-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ERα. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines. Published by Elsevier Ltd.

  3. Effect of estrogen receptor-alpha (ESR1 gene polymorphism on high density lipoprotein levels in response to hormone replacement therapy

    Directory of Open Access Journals (Sweden)

    N.C. Nogueira-de-Souza

    2009-12-01

    Full Text Available Studies have shown that estrogen replacement therapy and estrogen plus progestin replacement therapy alter serum levels of total, LDL and HDL cholesterol levels. However, HDL cholesterol levels in women vary considerably in response to hormone replacement therapy (HRT. A significant portion of the variability of these levels has been attributed to genetic factors. Therefore, we investigated the influence of estrogen receptor-alpha (ESR1 gene polymorphisms on HDL levels in response to postmenopausal HRT. We performed a prospective cohort study on 54 postmenopausal women who had not used HRT before the study and had no significant general medical illness. HRT consisted of conjugated equine estrogen and medroxyprogesterone acetate continuously for 1 year. The lipoprotein levels were measured from blood samples taken before the start of therapy and after 1 year of HRT. ESR1 polymorphism (MspI C>T, HaeIII C>T, PvuII C>T, and XbaI A>G frequencies were assayed by restriction fragment length polymorphism. A general linear model was used to describe the relationships between HDL levels and genotypes after adjusting for age. A significant increase in HDL levels was observed after HRT (P = 0.029. Women with the ESR1 PvuII TT genotype showed a statistically significant increase in HDL levels after HRT (P = 0.032. No association was found between other ESR1 polymorphisms and HDL levels. According to our results, the ESR1 PvuII TT genotype was associated with increased levels of HDL after 1 year of HRT.

  4. CERAPP: Collaborative Estrogen Receptor Activity Prediction Project

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data from a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project) demonstrating using predictive computational...

  5. Relationships among estrogen receptor, oxytocin and vasopressin gene expression and social interaction in male mice.

    Science.gov (United States)

    Murakami, G; Hunter, R G; Fontaine, C; Ribeiro, A; Pfaff, D

    2011-08-01

    The incidence of social disorders such as autism and schizophrenia is significantly higher in males, and the presentation more severe, than in females. This suggests the possible contribution of sex hormones to the development of these psychiatric disorders. There is also evidence that these disorders are highly heritable. To contribute toward our understanding of the mechanisms underlying social behaviors, particularly social interaction, we assessed the relationship of social interaction with gene expression for two neuropeptides, oxytocin (OT) and arginine vasopressin (AVP), using adult male mice. Social interaction was positively correlated with: oxytocin receptor (OTR) and vasopressin receptor (V1aR) mRNA expression in the medial amygdala; and OT and AVP mRNA expression in the paraventricular nucleus of the hypothalamus (PVN). When mice representing extremes of social interaction were compared, all of these mRNAs were more highly expressed in high social interaction mice than in low social interaction mice. OTR and V1aR mRNAs were highly correlated with estrogen receptor α (ERα) mRNA in the medial amygdala, and OT and AVP mRNAs with estrogen receptor β (ERβ) mRNA in the PVN, indicating that OT and AVP systems are tightly regulated by estrogen receptors. A significant difference in the level of ERα mRNA in the medial amygdala between high and low social interaction mice was also observed. These results support the hypothesis that variations of estrogen receptor levels are associated with differences in social interaction through the OT and AVP systems, by upregulating gene expression for those peptides and their receptors. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  6. Synthesis of Triphenylethylene Bisphenols as Aromatase Inhibitors That Also Modulate Estrogen Receptors.

    Science.gov (United States)

    Lv, Wei; Liu, Jinzhong; Skaar, Todd C; O'Neill, Elizaveta; Yu, Ge; Flockhart, David A; Cushman, Mark

    2016-01-14

    A series of triphenylethylene bisphenol analogues of the selective estrogen receptor modulator (SERM) tamoxifen were synthesized and evaluated for their abilities to inhibit aromatase, bind to estrogen receptor α (ER-α) and estrogen receptor β (ER-β), and antagonize the activity of β-estradiol in MCF-7 human breast cancer cells. The long-range goal has been to create dual aromatase inhibitor (AI)/selective estrogen receptor modulators (SERMs). The hypothesis is that in normal tissue the estrogenic SERM activity of a dual AI/SERM could attenuate the undesired effects stemming from global estrogen depletion caused by the AI activity of a dual AI/SERM, while in breast cancer tissue the antiestrogenic SERM activity of a dual AI/SERM could act synergistically with AI activity to enhance the antiproliferative effect. The potent aromatase inhibitory activities and high ER-α and ER-β binding affinities of several of the resulting analogues, together with the facts that they antagonize β-estradiol in a functional assay in MCF-7 human breast cancer cells and they have no E/Z isomers, support their further development in order to obtain dual AI/SERM agents for breast cancer treatment.

  7. Estrogen receptor signaling in prostate cancer: Implications for carcinogenesis and tumor progression.

    Science.gov (United States)

    Bonkhoff, Helmut

    2018-01-01

    The androgen receptor (AR) is the classical target for prostate cancer prevention and treatment, but more recently estrogens and their receptors have also been implicated in prostate cancer development and tumor progression. Recent experimental and clinical data were reviewed to elucidate pathogenetic mechanisms how estrogens and their receptors may affect prostate carcinogenesis and tumor progression. The estrogen receptor beta (ERβ) is the most prevalent ER in the human prostate, while the estrogen receptor alpha (ERα) is restricted to basal cells of the prostatic epithelium and stromal cells. In high grade prostatic intraepithelial neoplasia (HGPIN), the ERα is up-regulated and most likely mediates carcinogenic effects of estradiol as demonstrated in animal models. The partial loss of the ERβ in HGPIN indicates that the ERβ acts as a tumor suppressor. The tumor promoting function of the TMPRSS2-ERG fusion, a major driver of prostate carcinogenesis, is triggered by the ERα and repressed by the ERβ. The ERβ is generally retained in hormone naïve and metastatic prostate cancer, but is partially lost in castration resistant disease. The progressive emergence of the ERα and ERα-regulated genes (eg, progesterone receptor (PR), PS2, TMPRSS2-ERG fusion, and NEAT1) during prostate cancer progression and hormone refractory disease suggests that these tumors can bypass the AR by using estrogens and progestins for their growth. In addition, nongenomic estrogen signaling pathways mediated by orphan receptors (eg, GPR30 and ERRα) has also been implicated in prostate cancer progression. Increasing evidences demonstrate that local estrogen signaling mechanisms are required for prostate carcinogenesis and tumor progression. Despite the recent progress in this research topic, the translation of the current information into potential therapeutic applications remains highly challenging and clearly warrants further investigation. © 2017 Wiley Periodicals, Inc.

  8. Twenty years of the G protein-coupled estrogen receptor GPER: Historical and personal perspectives.

    Science.gov (United States)

    Barton, Matthias; Filardo, Edward J; Lolait, Stephen J; Thomas, Peter; Maggiolini, Marcello; Prossnitz, Eric R

    2018-02-01

    Estrogens play a critical role in many aspects of physiology, particularly female reproductive function, but also in pathophysiology, and are associated with protection from numerous diseases in premenopausal women. Steroids and the effects of estrogen have been known for ∼90 years, with the first evidence for a receptor for estrogen presented ∼50 years ago. The original ancestral steroid receptor, extending back into evolution more than 500 million years, was likely an estrogen receptor, whereas G protein-coupled receptors (GPCRs) trace their origins back into history more than one billion years. The classical estrogen receptors (ERα and ERβ) are ligand-activated transcription factors that confer estrogen sensitivity upon many genes. It was soon apparent that these, or novel receptors may also be responsible for the "rapid"/"non-genomic" membrane-associated effects of estrogen. The identification of an orphan GPCR (GPR30, published in 1996) opened a new field of research with the description in 2000 that GPR30 expression is required for rapid estrogen signaling. In 2005-2006, the field was greatly stimulated by two studies that described the binding of estrogen to GPR30-expressing cell membranes, followed by the identification of a GPR30-selective agonist (that lacked binding and activity towards ERα and ERβ). Renamed GPER (G protein-coupled estrogen receptor) by IUPHAR in 2007, the total number of articles in PubMed related to this receptor recently surpassed 1000. In this article, the authors present personal perspectives on how they became involved in the discovery and/or advancement of GPER research. These areas include non-genomic effects on vascular tone, receptor cloning, molecular and cellular biology, signal transduction mechanisms and pharmacology of GPER, highlighting the roles of GPER and GPER-selective compounds in diseases such as obesity, diabetes, and cancer and the obligatory role of GPER in propagating cardiovascular aging, arterial

  9. Localization of Estrogen Receptors α and β in the Articular Surface of the Rat Femur

    International Nuclear Information System (INIS)

    Oshima, Yasushi; Matsuda, Ken-ichi; Yoshida, Atsuhiko; Watanabe, Nobuyoshi; Kawata, Mitsuhiro; Kubo, Toshikazu

    2007-01-01

    It has been suggested that the degradation of the articular cartilage and osteoarthritis (OA) are associated with gender and the estrogen hormone. Although many investigators have reported the presence of the estrogen receptors (ERs) α and β in the articular cartilage, the localization of these receptors and the difference in their in vivo expression have not yet been clearly demonstrated. We performed immunofluorescence staining of ERα and ERβ to elucidate the localization of the ERs and to note the effects of gender and the aging process on these receptors. The results revealed that ERα and ERβ were expressed in the articular cartilage and subchondral bone layers of adult rats of both sexes. We also observed the high expression of these receptors in immature rats. In contrast, their expression levels decreased in an ovariectomised model, as a simulation of postmenopause, and in aged female rats. Therefore, this study suggests the direct effects of estrogen and ER expression on articular surface metabolism

  10. Participation of Water in the Binding of Estrogen Receptor with Estrogen Responsive Element in vitro.

    Science.gov (United States)

    Zhu, Guo-Zhang; Tang, Guo-Qing; Ruan, Kang-Cheng; Gong, Yue-Ting; Zhang, Yong-Lian

    1998-01-01

    Many reports have showed that bound water was involved in the interaction between/among the macromolecules. However, it has not been reported whether bound water is also involved in the binding of trans-factors and cis-elements in the regulation of the eukaryotic gene trans-cription or not. Preliminary studies have been made on the effect of bound water on the binding of estrogen receptor with estrogen responsive element in vitro. In the gel retardation assay using the cytosol extract of rat uterus as the supplier of estrogen receptor and 32 bp oligonucleotide containing a concensus vitellogenin A(2) ERE as the probe, various cosolvents, such as glycerol, sucrose, N-dimethylformamide and dimethylsulfoxide, were added respectively to the reaction mixture in varying concentrations to regulate the osmotic pressure. The results indicated that the binding of ER-ERE was enhanced with the increase in the final concentration of these individual cosolvents. On the other hand, when the reaction was carried out under an increasing hydrostatic pressure, the ER-ERE binding was decreased sharply. After decompression the binding of ER-ERE was gradually restored to the normal level with the lapse of time. These results suggested that bound water was directly involved in the binding of ER-ERE and may play an important role in the regulation of the eukaryotic gene transcription.

  11. Estrogen receptor determination in endometrial carcinoma: ligand binding assay versus enzyme immunoassay

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, Anette Lynge; Lyndrup, J

    1995-01-01

    We compared concentrations of cytosolic estrogen receptors (ERc) measured in 35 postmenopausal endometrial carcinomas by ligand binding method (LBA) (dextran-coated charcoal assay) and enzyme immunoassay (EIA). Correlations between ERc, nuclear estrogen receptors (ERn) determined by EIA......, and cytosolic progesterone receptors (PR) measured by LBA were also studied. While ERc concentrations determined by LBA and EIA were highly correlated (r: 0.94), ERc values detected by LBA were approximately twice those found by EIA (median values of ERc: 155 vs. 64 fmol/mg cytosol protein, DCC vs. EIA......). The percentages of ERc positive tumors were 89% by LBA and 77% by EIA. The median fraction of total ER present as ERn was 63%. PR levels correlated positively with ERn concentrations (r: 0.73). We explore possible reasons why greater concentrations of ERc are determined by estradiol binding than by the ER-EIA kit...

  12. Estrogen regulation of chicken riboflavin carrier protein gene is mediated by ERE half sites without direct binding of estrogen receptor.

    Science.gov (United States)

    Bahadur, Urvashi; Ganjam, Goutham K; Vasudevan, Nandini; Kondaiah, Paturu

    2005-02-28

    Estrogen is an important steroid hormone that mediates most of its effects on regulation of gene expression by binding to intracellular receptors. The consensus estrogen response element (ERE) is a 13bp palindromic inverted repeat with a three nucleotide spacer. However, several reports suggest that many estrogen target genes are regulated by diverse elements, such as imperfect EREs and ERE half sites (ERE 1/2), which are either the proximal or the distal half of the palindrome. To gain more insight into ERE half site-mediated gene regulation, we used a region from the estrogen-regulated chicken riboflavin carrier protein (RCP) gene promoter that contains ERE half sites. Using moxestrol, an analogue of estrogen and transient transfection of deletion and mutation containing RCP promoter/reporter constructs in chicken hepatoma (LMH2A) cells, we identified an estrogen response unit (ERU) composed of two consensus ERE 1/2 sites and one non-consensus ERE 1/2 site. Mutation of any of these sites within this ERU abolishes moxestrol response. Further, the ERU is able to confer moxestrol responsiveness to a heterologous promoter. Interestingly, RCP promoter is regulated by moxestrol in estrogen responsive human MCF-7 cells, but not in other cell lines such as NIH3T3 and HepG2 despite estrogen receptor-alpha (ER-alpha) co transfection. Electrophoretic mobility shift assays (EMSAs) with promoter regions encompassing the half sites and nuclear extracts from LMH2A cells show the presence of a moxestrol-induced complex that is abolished by a polyclonal anti-ERalpha antibody. Surprisingly, estrogen receptor cannot bind to these promoter elements in isolation. Thus, there appears to be a definite requirement for some other factor(s) in addition to estrogen receptor, for the generation of a suitable response of this promoter to estrogen. Our studies therefore suggest a novel mechanism of gene regulation by estrogen, involving ERE half sites without direct binding of ER to the

  13. Up-regulation of PI3K/Akt signaling by 17β-estradiol through activation of estrogen receptor-α, but not estrogen receptor-β, and stimulates cell growth in breast cancer cells

    International Nuclear Information System (INIS)

    Lee, Young-Rae; Park, Jinny; Yu, Hong-Nu; Kim, Jong-Suk; Youn, Hyun Jo; Jung, Sung Hoo

    2005-01-01

    Estrogen stimulates cell proliferation in breast cancer. The biological effects of estrogen are mediated through two intracellular receptors, estrogen receptor-α (ERα) and estrogen receptor-β (ERβ). However, the role of ERs in the proliferative action of estrogen is not well established. Recently, it has been known that ER activates phosphatidylinositol-3-OH kinase (PI3K) through binding with the p85 regulatory subunit of PI3K. Therefore, possible mechanisms may include ER-mediated phosphoinositide metabolism with subsequent formation of phosphatidylinositol-3,4,5-trisphosphate (PIP 3 ), which is generated from phosphatidylinositol 4,5-bisphosphate via PI3K activation. The present study demonstrates that 17β-estradiol (E2) up-regulates PI3K in an ERα-dependent manner, but not ERβ, and stimulates cell growth in breast cancer cells. In order to study this phenomenon, we have treated ERα-positive MCF-7 cells and ERα-negative MDA-MB-231 cells with 10 nM E2. Treatment of MCF-7 cells with E2 resulted in a marked increase in PI3K (p85) expression, which paralleled an increase in phospho-Akt (Ser-473) and PIP 3 level. These observations also correlated with an increased activity to E2-induced cell proliferation. However, these effects of E2 on breast cancer cells were not observed in the MDA-MB-231 cell line, indicating that the E2-mediated up-regulation of PI3K/Akt pathway is ERα-dependent. These results suggest that estrogen activates PI3K/Akt signaling through ERα-dependent mechanism in MCF-7 cells

  14. Circadian Rhythm of Hepatic Cytosolic and Nuclear Estrogen and Androgen Receptors

    Science.gov (United States)

    FRANCAVILLA, ANTONIO; EAGON, PATRICIA K.; DiLEO, ALFREDO; VAN THIEL, DAVID H.; PANELLA, CARMINE; POLIMENO, LORENZO; AMORUSO, CINZIA; INGROSSO, MARCELLO; AQUILINO, A. MARIA; STARZL, THOMAS E.

    2010-01-01

    Mammalian liver is a sex steroid-responsive tissue. The effects of these hormones presumably are mediated by hepatic estrogen receptors (ER) and androgen receptors (AR). Serum levels of sex hormones display circadian rhythms. Further, estrogens and androgens are commonly administered; administration of these agents is associated frequently with liver disease. Therefore, we investigated whether the cytosolic and nuclear sex steroid receptors also display a similar circadian rhythm, and whether variations occurred in the distribution of receptors between cytosolic and nuclear compartments. Animals were killed every 4 h from midnight till the following midnight; cytosolic and nuclear levels of both ER and AR were measured. Cytosolic ER reached a maximum level at 4 AM, and a minimum at 8 PM and midnight of both days. Nuclear ER was highest at 8 AM and lowest at 4 PM and 8 PM, a pattern which parallels variations in serum estradiol levels. Cytosolic AR was highest at 8 PM and lowest at midnight and 4 AM. Nuclear AR was highest at 4 AM and lowest at 4 PM and 8 PM. The highest level of nuclear AR does not correspond to the maximum serum testosterone level, which occurred at 4 PM. The total hepatic content of both ER and AR was not constant over the 24-h period, but varied considerably with time of day. These studies suggest that both ER and AR show a distinct circadian rhythm in subcellular compartmentalization, and that total hepatic content of ER and AR varies significantly during a 24-h period. PMID:3710067

  15. Ligands specify estrogen receptor alpha nuclear localization and degradation

    Directory of Open Access Journals (Sweden)

    Caze-Subra Stéphanie

    2010-12-01

    Full Text Available Abstract Background The estrogen receptor alpha (ERα is found predominately in the nucleus, both in hormone stimulated and untreated cells. Intracellular distribution of the ERα changes in the presence of agonists but the impact of different antiestrogens on the fate of ERα is a matter of debate. Results A MCF-7 cell line stably expressing GFP-tagged human ERα (SK19 cell line was created to examine the localization of ligand-bound GFP-ERα. We combined digitonin-based cell fractionation analyses with fluorescence and immuno-electron microscopy to determine the intracellular distribution of ligand-bound ERα and/or GFP-ERα. Using fluorescence- and electron microscopy we demonstrate that both endogenous ERα and GFP-ERα form numerous nuclear focal accumulations upon addition of agonist, 17β-estradiol (E2, and pure antagonists (selective estrogen regulator disruptor; SERD, ICI 182,780 or RU58,668, while in the presence of partial antagonists (selective estrogen regulator modulator; SERM, 4-hydroxytamoxifen (OHT or RU39,411, diffuse nuclear staining persisted. Digitonin based cell fractionation analyses confirmed that endogenous ERα and GFP-ERα predominantly reside in the nuclear fraction. Overall ERα protein levels were reduced after estradiol treatment. In the presence of SERMs ERα was stabilized in the nuclear soluble fraction, while in the presence of SERDs protein levels decreased drastically and the remaining ERα was largely found in a nuclear insoluble fraction. mRNA levels of ESR1 were reduced compared to untreated cells in the presence of all ligands tested, including E2. E2 and SERDs induced ERα degradation occurred in distinct nuclear foci composed of ERα and the proteasome providing a simple explanation for ERα sequestration in the nucleus. Conclusions Our results indicate that chemical structure of ligands directly affect the nuclear fate and protein turnover of the estrogen receptor alpha independently of their impact on

  16. Phytoestrogens and Mycoestrogens Induce Signature Structure Dynamics Changes on Estrogen Receptor α

    Directory of Open Access Journals (Sweden)

    Xueyan Chen

    2016-08-01

    Full Text Available Endocrine disrupters include a broad spectrum of chemicals such as industrial chemicals, natural estrogens and androgens, synthetic estrogens and androgens. Phytoestrogens are widely present in diet and food supplements; mycoestrogens are frequently found in grains. As human beings and animals are commonly exposed to phytoestrogens and mycoestrogens in diet and environment, it is important to understand the potential beneficial or hazardous effects of estrogenic compounds. Many bioassays have been established to study the binding of estrogenic compounds with estrogen receptor (ER and provided rich data in the literature. However, limited assays can offer structure information with regard to the ligand/ER complex. Our current study surveys the global structure dynamics changes for ERα ligand binding domain (LBD when phytoestrogens and mycoestrogens bind. The assay is based on the structure dynamics information probed by hydrogen deuterium exchange mass spectrometry and offers a unique viewpoint to elucidate the mechanism how phytoestrogens and mycoestrogens interact with estrogen receptor. The cluster analysis based on the hydrogen deuterium exchange (HDX assay data reveals a unique pattern when phytoestrogens and mycoestrogens bind with ERα LBD compared to that of estradiol and synthetic estrogen modulators. Our study highlights that structure dynamics could play an important role in the structure function relationship when endocrine disrupters interact with estrogen receptors.

  17. The selective estrogen receptor modulators (SERMs) raloxifene and tamoxifen improve ANP levels and decrease nuclear translocation of NF-kB in estrogen-deficient rats.

    Science.gov (United States)

    Lamas, Aline Z; Nascimento, Andrews M; Medeiros, Ana Raquel S; Caliman, Izabela F; Dalpiaz, Polyana L M; Firmes, Luciana B; Sousa, Glauciene J; Oliveira, Phablo Wendell C; Andrade, Tadeu U; Reis, Adelina M; Gouvea, Sônia A; Bissoli, Nazaré S

    2017-08-01

    The selective estrogen receptor modulators (SERMs) raloxifene and tamoxifen are used for the treatment of osteoporosis and cancer, respectively, in women. The impairment of both the Atrial Natriuretic Peptide (ANP) cell signaling system and the translocation of nuclear factor-kappa B (NF-kB) to the cell nucleus are associated with detrimental cardiovascular effects and inflammation. The effects of SERMs on these parameters in the cardiac tissue of estrogen-deficient rats has not been reported. We investigated the effects of raloxifene and tamoxifen on ANP signaling, p65 NF-kB nuclear translocation, cardiac histology and contractility. Female rats were divided into five groups: control (SHAM), ovariectomized (OVX), OVX-treated 17-β-estradiol (E), OVX-treated raloxifene (RLX) and OVX-treated tamoxifen (TAM). The treatments started 21days after ovariectomy and continued for 14days. Ovariectomy reduced ANP mRNA in the left atrium (LA), decreased the content of ANP protein in the LA and in plasma, and increased the level of p65 NF-kB nuclear translocation in the left ventricle. Both 17-β-estradiol and SERMs were able to reverse these alterations, which were induced by the estrogen deficient state. The hemodynamic and cardiac structural parameters analyzed in the present work were not modified by the interventions. Our study demonstrates, for the first time, the additional benefits of raloxifene and tamoxifen in an estrogen-deficient state. These include the normalization of plasmatic and cardiac ANP levels and cardiac p65 NF-kB translocation. Therefore, these treatments promote cardiovascular protection and may contribute to the prevention of cardiac dysfunction observed long-term in postmenopausal women. Copyright © 2017. Published by Elsevier Urban & Partner Sp. z o.o.

  18. Mitochondria: Target organelles for estrogen action

    Directory of Open Access Journals (Sweden)

    Małgorzata Chmielewska

    2017-06-01

    Full Text Available Estrogens belong to a group of sex hormones, which have been shown to act in multidirectional way. Estrogenic effects are mediated by two types of intracellular receptors: estrogen receptor 1 (ESR1 and estrogen receptor 2 (ESR2. There are two basic mechanisms of estrogen action: 1 classical-genomic, in which the ligand-receptor complex acts as a transcriptional factor and 2 a nongenomic one, which is still not fully understood, but has been seen to lead to distinct biological effects, depending on tissue and ligand type. It is postulated that nongenomic effects may be associated with membrane signaling and the presence of classical nuclear receptors within the cell membrane. Estrogens act in a multidirectional way also within cell organelles. It is assumed that there is a mechanism which manages the migration of ESR into the mitochondrial membrane, wherein the exogenous estrogen affect the morphology of mitochondria. Estrogen, through its receptor, can directly modulate mitochondrial gene expression. Moreover, by regulating the level of reactive oxygen species, estrogens affect the biology of mitochondria. The considerations presented in this paper indicate the pleiotropic effects of estrogens, which represent a multidirectional pathway of signal transduction.

  19. Prognostic Value of Estrogen Receptor alpha and Progesterone Receptor Conversion in Distant Breast Cancer Metastases

    NARCIS (Netherlands)

    Hoefnagel, Laurien D. C.; Moelans, Cathy B.; Meijer, S. L.; van Slooten, Henk-Jan; Wesseling, Pieter; Wesseling, Jelle; Westenend, Pieter J.; Bart, Joost; Seldenrijk, Cornelis A.; Nagtegaal, Iris D.; Oudejans, Joost; van der Valk, Paul; van Gils, Carla H.; van der Wall, Elsken; van Diest, Paul J.

    2012-01-01

    BACKGROUND: Changes in the receptor profile of primary breast cancers to their metastases (receptor conversion) have been described for the estrogen receptor alpha (ER alpha) and progesterone receptor (PR). The purpose of this study was to evaluate the impact of receptor conversion for ER alpha and

  20. Estrogen effects on angiotensin receptors are modulated by pituitary in female rats

    International Nuclear Information System (INIS)

    Douglas, J.G.

    1987-01-01

    The present studies were designed to test the hypothesis that changes in angiotensin II (ANG II) receptors might modulate the layered target tissue responsiveness accompanying estradiol administration. Estradiol was infused continuously in oophorectomized female rats. Aldosterone was also infused in control and experimental animals to avoid estrogen-induced changes in renin and ANG II. ANG II binding constants were determined in radioreceptor assays. Estradiol increased binding site concentration in adrenal glomerulosa by 76% and decreased binding sites of uterine myometrium and glomeruli by 45 and 24%, respectively. There was an accompanying increase in the affinity of ANG II binding to adrenal glomerulosa and uterine myometrium. Because estrogen is a potent stimulus of prolactin release from the pituitary of rodents, studies were also designed to test the hypothesis that prolactin may mediate some or all of the estrogen-induced effects observed. Hypophysectomy abolished estradiol stimulation of prolactin release and most ANG II receptor changes. Prolactin administration to pituitary intact rats was associated with a 50% increase in receptor density of adrenal glomerulosa simulating estradiol administration. However, the changes in glomeruli and uterine myometrium were opposite in that both tissues also increased receptor density, suggesting that prolactin was not the sole mediator of the estrogen-induced receptor changes. In conclusion, regulation of ANG II receptors in a number of diverse target tissues by estradiol is complex with contributions from estrogens and pituitary factors, which include but do not exclusively involve prolactin

  1. Selective estrogen receptor modulators (SERMs): Mechanisms of anticarcinogenesis and drug resistance

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Joan S. [Fox Chase Cancer Center, Alfred G. Knudson Chair of Cancer Research, 333 Cottman Avenue, Philadelphia, PA 19111 (United States); Jordan, V. Craig [Fox Chase Cancer Center, Alfred G. Knudson Chair of Cancer Research, 333 Cottman Avenue, Philadelphia, PA 19111 (United States)]. E-mail: v.craig.jordan@fccc.edu

    2005-12-11

    Despite the beneficial effects of estrogens in women's health, there is a plethora of evidence that suggest an important role for these hormones, particularly 17{beta}-estradiol (E{sub 2}), in the development and progression of breast cancer. Most estrogenic responses are mediated by estrogen receptors (ERs), either ER{alpha} or ER{beta}, which are members of the nuclear receptor superfamily of ligand-dependent transcription factors. Selective estrogen receptor modulators (SERMs) are ER ligands that in some tissues (i.e. bone and cardiovascular system) act like estrogens but block estrogen action in others. Tamoxifen is the first SERM that has been successfully tested for the prevention of breast cancer in high-risk women and is currently approved for the endocrine treatment of all stages of ER-positive breast cancer. Raloxifene, a newer SERM originally developed for osteoporosis, also appears to have preventive effect on breast cancer incidence. Numerous studies have examined the molecular mechanisms for the tissue selective action of SERMs, and collectively they indicate that different ER ligands induce distinct conformational changes in the receptor that influence its ability to interact with coregulatory proteins (i.e. coactivators and corepressors) critical for the regulation of target gene transcription. The relative expression of coactivators and corepressors, and the nature of the ER and its target gene promoter also affect SERM biocharacter. This review summarizes the therapeutic application of SERMs in medicine; particularly breast cancer, and highlights the emerging understanding of the mechanism of action of SERMs in select target tissues, and the inevitable development of resistance.

  2. Putative Biomarkers and Targets of Estrogen Receptor Negative Human Breast Cancer

    Directory of Open Access Journals (Sweden)

    Stephen W. Byers

    2011-07-01

    Full Text Available Breast cancer is a progressive and potentially fatal disease that affects women of all ages. Like all progressive diseases, early and reliable diagnosis is the key for successful treatment and annihilation. Biomarkers serve as indicators of pathological, physiological, or pharmacological processes. Her2/neu, CA15.3, estrogen receptor (ER, progesterone receptor (PR, and cytokeratins are biomarkers that have been approved by the Food and Drug Administration for disease diagnosis, prognosis, and therapy selection. The structural and functional complexity of protein biomarkers and the heterogeneity of the breast cancer pathology present challenges to the scientific community. Here we review estrogen receptor-related putative breast cancer biomarkers, including those of putative breast cancer stem cells, a minor population of estrogen receptor negative tumor cells that retain the stem cell property of self renewal. We also review a few promising cytoskeleton targets for ER alpha negative breast cancer.

  3. Estrogen receptor beta in prostate cancer: friend or foe?

    Science.gov (United States)

    Nelson, Adam W; Tilley, Wayne D; Neal, David E; Carroll, Jason S

    2014-08-01

    Prostate cancer is the commonest, non-cutaneous cancer in men. At present, there is no cure for the advanced, castration-resistant form of the disease. Estrogen has been shown to be important in prostate carcinogenesis, with evidence resulting from epidemiological, cancer cell line, human tissue and animal studies. The prostate expresses both estrogen receptor alpha (ERA) and estrogen receptor beta (ERB). Most evidence suggests that ERA mediates the harmful effects of estrogen in the prostate, whereas ERB is tumour suppressive, but trials of ERB-selective agents have not translated into improved clinical outcomes. The role of ERB in the prostate remains unclear and there is increasing evidence that isoforms of ERB may be oncogenic. Detailed study of ERB and ERB isoforms in the prostate is required to establish their cell-specific roles, in order to determine if therapies can be directed towards ERB-dependent pathways. In this review, we summarise evidence on the role of ERB in prostate cancer and highlight areas for future research. © 2014 Society for Endocrinology.

  4. Estrogenic activity and estrogen receptor β binding of the UV filter 3-benzylidene camphor Comparison with 4-methylbenzylidene camphor

    International Nuclear Information System (INIS)

    Schlumpf, Margret; Jarry, Hubert; Wuttke, Wolfgang; Ma, Risheng; Lichtensteiger, Walter

    2004-01-01

    UV filters represent new classes of estrogenic [Environ. Health Perspect. 109 (2001) 239] or antiandrogenic [Toxicol. Sci. 74 (2003) 43] chemicals. We tested 3-benzylidene camphor (3-BC), reported as estrogenic in fish [Pharmacol. Toxicol. 91 (2002) 204], and mammalian systems in comparison to 4-methylbenzylidene camphor (4-MBC), shown to be active in rats, and analyzed binding to estrogen receptor subtypes. 3-BC and 4-MBC stimulated MCF-7 cell proliferation (EC 50 : 0.68 and 3.9 μM). The uterotrophic assay of 3-BC (oral gavage) in immature rats showed unexpected potency with ED50 45.3 mg/kg per day; lowest effective dose 2 mg/kg per day, and maximum effect with 70% of ethinylestradiol. After comparing with literature data, we found that the oral 3-BC was considerably more potent than oral bisphenol A and almost as active as subcutaneous genistein. 3-BC and 4-MBC displaced 16α 125 I-estradiol from porcine uterine cytosolic receptors (IC 50 : 14.5 and 112 μM), and from recombinant human estrogen receptor β (hERβ) (IC 50 : 3-BC, 11.8 μM; 4-MBC, 35.3 μM), whereas no displacement was detected at human estrogen receptor α (hERα) up to 3 mM. This subtype selectivity makes the two camphor derivatives interesting model compounds. Their activity on immature rat uterus is not easily explained by ERβ activation. It cannot be excluded that active metabolites with possibly different receptor binding characteristics are formed in vivo

  5. Bromine-80m-labeled estrogens: Auger-electron emitting, estrogen receptor-directed ligands with potential for therapy of estrogen receptor positive cancers

    International Nuclear Information System (INIS)

    DeSombre, E.R.; Mease, R.C.; Hughes, A.; Harper, P.V.; DeJesus, O.T.; Friedman, A.M.

    1988-01-01

    A triphenylbromoethylene, 1,1-bis(p-hydroxyphenyl)-2-bromo-2-phenylethylene, Br-BHPE, and a bromosteroidal estrogen, 17α- bromovinylestradiol, BrVE 2 , were labeled with the Auger electron emitting nuclide bromine-80m, prepared by the [p,n] reaction with 80 Se. To assess their potential as estrogen receptor (ER) directed therapeutic substrates the bromine-80m labeled estrogens were injected into immature female rats and the tissue distribution studied at 0.5 and 2 hours. Both radiobromoestrogens showed substantial diethylstilbesterol (DES)-inhibitable localization in the ER rich tissues, uterus, pituitary, ovary and vagina at both time points. While the percent dose per gram tissue was higher for the Br-BHPE, the BrVE 2 showed higher tissue to blood ratios, especially at 2 hr, reflecting the lower blood concentrations of radiobromine following administration of the steroidal bromoestrogen. Comparing intraperitoneal, intravenous and subcutaneous routes of administration for the radiobromine labeled Br-BHPE, the intraperitoneal route was particularly advantageous to provide maximum, DES-inhibitable concentrations in the peritoneal, ER-rich target organs, the uterus, ovary and vagina. While uterine concentrations after BrBHPE were from 10--48% dose/g and after BrVE 2 were 15--25% dose/g, similar treatment with /sup 80m/Br as sodium bromide showed uniform low concentrations in all tissues at about the levels seen in blood. The effective specific activity of [/sup 80m/Br]BrBHPE, assayed by specific binding to ER in rat uterine cytosol, was 8700 Ci/mmole. 23 refs., 9 figs., 2 tabs

  6. Homology-modeled ligand-binding domains of medaka estrogen receptors and androgen receptors: A model system for the study of reproduction

    International Nuclear Information System (INIS)

    Cui Jianzhou; Shen Xueyan; Yan Zuowei; Zhao Haobin; Nagahama, Yoshitaka

    2009-01-01

    Estrogen and androgen and their receptors play critical roles in physiological processes such as sexual differentiation and development. Using the available structural models for the human estrogen receptors alpha and beta and androgen receptor as templates, we designed in silico agonist and antagonist models of medaka estrogen receptor (meER) alpha, beta-1, and beta-2, and androgen receptor (meAR) alpha and beta. Using these models, we studied (1) the structural relationship between the ligand-binding domains (LBDs) of ERs and ARs of human and medaka, and (2) whether medaka ER and AR can be potential models for studying the ligand-binding activities of various agonists and antagonists of these receptors by docking analysis. A high level of conservation was observed between the sequences of the ligand-binding domains of meERα and huERα, meERβ1 and huERβ, meERβ2, and huERβ with 62.8%, 66.4%, and 65.1% identity, respectively. The sequence conservation between meARα and huAR, meARβ, and huAR was found with 70.1% and 61.0% of identity, respectively. Thirty-three selected endocrine disrupting chemicals (EDCs), including both agonists and antagonists, were docked into the LBD of ER and AR, and the corresponding docking score for medaka models and human templates were calculated. In order to confirm the conservation of the overall geometry and the binding pocket, the backbone root mean square deviation (RMSD) for Cα atoms was derived from the structure superposition of all 10 medaka homology models to the six human templates. Our results suggested conformational conservation between the ERs and ARs of medaka and human, Thus, medaka could be highly useful as a model system for studies involving estrogen and androgen interaction with their receptors.

  7. Estrogen receptor-α mediates the detrimental effects of neonatal diethylstilbestrol (DES) exposure in the murine reproductive tract

    International Nuclear Information System (INIS)

    Couse, John F.; Korach, Kenneth S.

    2004-01-01

    It is generally believed that estrogen receptor-dependent and -independent pathways are involved in mediating the developmental effects of the synthetic estrogen, diethylstilbestrol (DES). However, the precise role and extent to which each pathway contributes to the resulting pathologies remains unknown. We have employed the estrogen receptor knockout (ERKO) mice, which lack either estrogen receptor-α (αERKO or estrogen receptor-β (βERKO), to gain insight into the contribution of each ER-dependent pathway in mediating the effects of neonatal DES exposure in the female and male reproductive tract tissues of the mouse. Estrogen receptor-α female mice exhibited complete resistance to the chronic effects of neonatal DES exposure that were obvious in exposed wild-type animals, including atrophy and epithelial squamous metaplasia in the uterus; proliferative lesions of the oviduct; and persistent cornification of the vaginal epithelium. DES-mediated reduction in uterine Hoxa10, Hoxa11 and Wnt7a expression that occurs wild-type females during the time of exposure was also absent in αERKO females. In the male, αERKO mice exhibited complete resistance to the chronic effects of neonatal DES exposure on the prostate, including decreased androgen receptor levels, epithelial hyperplasia, and increased basal cell proliferation. Although ERβ is highly expressed in the prostate epithelium, DES-exposed βERKO males exhibited all of the effects of neonatal DES exposure that were observed in similarly exposed wild-type males. Therefore, the lack of DES-effects on gene expression and tissue differentiation in the αERKO uterus and prostate provides unequivocal evidence of an obligatory role for ERα in mediating the detrimental actions of neonatal DES exposure in the murine reproductive tract

  8. Mouse models of estrogen receptor-positive breast cancer

    Directory of Open Access Journals (Sweden)

    Shakur Mohibi

    2011-01-01

    Full Text Available Breast cancer is the most frequent malignancy and second leading cause of cancer-related deaths among women. Despite advances in genetic and biochemical analyses, the incidence of breast cancer and its associated mortality remain very high. About 60 - 70% of breast cancers are Estrogen Receptor alpha (ER-α positive and are dependent on estrogen for growth. Selective estrogen receptor modulators (SERMs have therefore provided an effective targeted therapy to treat ER-α positive breast cancer patients. Unfortunately, development of resistance to endocrine therapy is frequent and leads to cancer recurrence. Our understanding of molecular mechanisms involved in the development of ER-α positive tumors and their resistance to ER antagonists is currently limited due to lack of experimental models of ER-α positive breast cancer. In most mouse models of breast cancer, the tumors that form are typically ER-negative and independent of estrogen for their growth. However, in recent years more attention has been given to develop mouse models that develop different subtypes of breast cancers, including ER-positive tumors. In this review, we discuss the currently available mouse models that develop ER-α positive mammary tumors and their potential use to elucidate the molecular mechanisms of ER-α positive breast cancer development and endocrine resistance.

  9. Global analysis of estrogen receptor beta binding to breast cancer cell genome reveals an extensive interplay with estrogen receptor alpha for target gene regulation

    Directory of Open Access Journals (Sweden)

    Papa Maria

    2011-01-01

    Full Text Available Abstract Background Estrogen receptors alpha (ERα and beta (ERβ are transcription factors (TFs that mediate estrogen signaling and define the hormone-responsive phenotype of breast cancer (BC. The two receptors can be found co-expressed and play specific, often opposite, roles, with ERβ being able to modulate the effects of ERα on gene transcription and cell proliferation. ERβ is frequently lost in BC, where its presence generally correlates with a better prognosis of the disease. The identification of the genomic targets of ERβ in hormone-responsive BC cells is thus a critical step to elucidate the roles of this receptor in estrogen signaling and tumor cell biology. Results Expression of full-length ERβ in hormone-responsive, ERα-positive MCF-7 cells resulted in a marked reduction in cell proliferation in response to estrogen and marked effects on the cell transcriptome. By ChIP-Seq we identified 9702 ERβ and 6024 ERα binding sites in estrogen-stimulated cells, comprising sites occupied by either ERβ, ERα or both ER subtypes. A search for TF binding matrices revealed that the majority of the binding sites identified comprise one or more Estrogen Response Element and the remaining show binding matrixes for other TFs known to mediate ER interaction with chromatin by tethering, including AP2, E2F and SP1. Of 921 genes differentially regulated by estrogen in ERβ+ vs ERβ- cells, 424 showed one or more ERβ site within 10 kb. These putative primary ERβ target genes control cell proliferation, death, differentiation, motility and adhesion, signal transduction and transcription, key cellular processes that might explain the biological and clinical phenotype of tumors expressing this ER subtype. ERβ binding in close proximity of several miRNA genes and in the mitochondrial genome, suggests the possible involvement of this receptor in small non-coding RNA biogenesis and mitochondrial genome functions. Conclusions Results indicate that the

  10. Ritonavir binds to and downregulates estrogen receptors: Molecular mechanism of promoting early atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jin [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Wang, Ying [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Su, Ke [Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Liu, Min [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Hu, Peng-Chao [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Ma, Tian; Li, Jia-Xi [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Wei, Lei [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Zheng, Zhongliang, E-mail: biochem@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072 (China); Yang, Fang, E-mail: fang-yang@whu.edu.cn [Department of Physiology, School of Medicine, Wuhan University, Wuhan 430071 (China)

    2014-10-01

    Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERβ expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17β-estradiol (E2), suggesting RTV acts as an antagonist for E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17β-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis. - Graphical abstract: RTV directly binds to ERα and Leu536 in the hydrophobic core of ligand binding domain is essential for the interaction. - Highlights: • RTV increases the thickness of rat coronary artery wall and foam cell formation. • RTV downregulates the expression of ERα and ERβ. • RTV inhibits ERα promoter activity. • RTV directly binds to ERα and the key amino acid is Leu536. • RTV inhibits the nuclear translocation of ERα and GPER.

  11. Ritonavir binds to and downregulates estrogen receptors: Molecular mechanism of promoting early atherosclerosis

    International Nuclear Information System (INIS)

    Xiang, Jin; Wang, Ying; Su, Ke; Liu, Min; Hu, Peng-Chao; Ma, Tian; Li, Jia-Xi; Wei, Lei; Zheng, Zhongliang; Yang, Fang

    2014-01-01

    Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERβ expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17β-estradiol (E2), suggesting RTV acts as an antagonist for E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17β-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis. - Graphical abstract: RTV directly binds to ERα and Leu536 in the hydrophobic core of ligand binding domain is essential for the interaction. - Highlights: • RTV increases the thickness of rat coronary artery wall and foam cell formation. • RTV downregulates the expression of ERα and ERβ. • RTV inhibits ERα promoter activity. • RTV directly binds to ERα and the key amino acid is Leu536. • RTV inhibits the nuclear translocation of ERα and GPER

  12. Biosensors paving the way to understanding the interaction between cadmium and the estrogen receptor alpha.

    Directory of Open Access Journals (Sweden)

    Peter Fechner

    Full Text Available Cadmium is a toxic heavy metal ubiquitously present in the environment and subsequently in the human diet. Cadmium has been proposed to disrupt the endocrine system, targeting in particular the estrogen signaling pathway already at environmentally relevant concentrations. Thus far, the reports on the binding affinity of cadmium towards human estrogen receptor alpha (hERα have been contradicting, as have been the reports on the in vivo estrogenicity of cadmium. Hence, the mode of interaction between cadmium and the receptor remains unclear. Here, we investigated the interaction between cadmium and hERα on a molecular level by applying a novel, label-free biosensor technique based on reflectometric interference spectroscopy (RIfS. We studied the binding of cadmium to hERα, and the conformation of the receptor following cadmium treatment. Our data reveals that cadmium interacts with the ligand binding domain (LBD of the ERα and affects the conformation of the receptor. However, the binding event, as well as the induced conformation change, greatly depends on the accessibility of the cysteine tails in the LBD. As the LBD cysteine residues have been reported as targets of post-translational modifications in vivo, we present a hypothesis according to which different cellular pools of ERα respond to cadmium differently. Our proposed theory could help to explain some of the previously contradicting results regarding estrogen-like activity of cadmium.

  13. Genetic variants of estrogen beta and leptin receptors may cause gynecomastia in adolescent.

    Science.gov (United States)

    Eren, Erdal; Edgunlu, Tuba; Korkmaz, Huseyin Anil; Cakir, Esra Deniz Papatya; Demir, Korcan; Cetin, Esin Sakalli; Celik, Sevim Karakas

    2014-05-15

    Gynecomastia is a benign breast enlargement in males that affects approximately one-third of adolescents. The exact mechanism is not fully understood; however, it has been proposed that estrogen receptors and aromatase enzyme activity may play important roles in the pathogenesis of gynecomastia. While many studies have reported that aromatase enzyme (CYP19) gene polymorphism is associated with gynecomastia, only one study has shown a relationship between estrogen receptor (ER) alpha and beta gene polymorphism and gynecomastia. Thus, the aim of this study was to evaluate the relationships between CYP19 (rs2414096), ER alpha (rs2234693), ER beta (rs4986938), leptin (rs7799039), and leptin receptor (rs1137101) gene polymorphisms and gynecomastia. This study included 107 male adolescents with gynecomastia and 97 controls. Total serum testosterone (T) and estradiol (E2) levels were measured, and DNA was extracted from whole blood using the PCR-RFLP technique. The polymorphic distributions of CYP19, ER alpha, ER beta, leptin and leptin receptor genes were compared. The median E2 level was 12.41 (5.00-65.40) pg/ml in the control group and 16.86 (2.58-78.47) pg/ml in the study group (pgynecomastia and leptin receptor rs1137101 (p=0.002) and ER beta receptor rs4986938 gene polymorphisms (p=0.002). According to our results, increased E2 level and ER beta gene rs4986938 polymorphism might explain why some adolescents have gynecomastia. Leptin receptor gene rs1137101 polymorphism might affect susceptibility to gynecomastia. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Aromatase and estrogen receptors in male reproduction.

    Science.gov (United States)

    Carreau, Serge; Delalande, Christelle; Silandre, Dorothée; Bourguiba, Sonia; Lambard, Sophie

    2006-02-26

    Aromatase is a terminal enzyme which transforms irreversibly androgens into estrogens and it is present in the endoplasmic reticulum of numerous tissues. We have demonstrated that mature rat germ cells express a functional aromatase with a production of estrogens equivalent to that of Leydig cells. In humans in addition to Leydig cells, we have shown the presence of aromatase in ejaculated spermatozoa and in immature germ cells. In most tissues, high affinity estrogen receptors, ERalpha and/or ERbeta, mediate the role of estrogens. Indeed, in human spermatozoa, we have successfully amplified ERbeta mRNA but the protein was not detectable. Using ERalpha antibody we have detected two proteins in human immature germ cells: one at the expected size 66 kDa and another at 46 kDa likely corresponding to the ERalpha isoform lacking exon 1. In spermatozoa only the 46 kDa isoform was present, and we suggest that it may be located on the membrane. In addition, in men genetically deficient in aromatase, it is reported that alterations of spermatogenesis occur both in terms of the number and motility of spermatozoa. All together, these observations suggest that endogenous estrogens are important in male reproduction.

  15. The polymorphism of estrogen receptor α is important for metabolic consequences associated with menopause.

    Science.gov (United States)

    Pinkas, Jarosław; Gujski, Mariusz; Wierzbińska-Stępniak, Anna; Owoc, Alfred; Bojar, Iwona

    2016-01-01

    Menopause is associated with multiple health and metabolic consequences resulting from the decrease in estrogens level. Women at postmenopausal age are burdened with a higher risk of cardiovascular diseases, and the main cause of mortality in this group is ischemic heart disease. Estrogen deficiency is related, among other things, with frequent occurrence of dislipidemia, cessation of the beneficial effect of estrogens on the vascular wall, increase in body weight characterized by unfavourable redistribution of fatty tissue, with an increased amount of visceral fat and reduction of so-called non-fatty body mass. Estrogens exert an effect on metabolism, mainly through the genomic mechanism. The presence of α and β estrogen receptors was found in many tissues and organs. Recently, attention was paid to the fact that the effect of estrogens action on tissues and organs may depend not only on distribution, but also on their polymorphic types. The article presents the latest approach to the problem of metabolic consequences resulting from menopause, according to the possessed α estrogen receptor polymorphism (ERα).Genes encoding for ERα have many polymorphic variants, the most important of which from the clinical aspect are two single nucleotide polymorphisms (SNPs) - Xba1 and PvuII. The review of literature indicates that ERα polymorphisms are of great importance with respect to the effect of estrogens on the functioning of the body of a woman after menopause, and may imply the development of many pathological states, including the prevention or development of metabolic disorders. Identifying ERα polymorphisms may be useful in case of estrogen therapy for menopausal women who may benefit from it.

  16. No substantial changes in estrogen receptor and estrogen-related receptor orthologue gene transcription in Marisa cornuarietis exposed to estrogenic chemicals

    OpenAIRE

    Beresford, N; Granger, DW; Pounds, NA; Rand-Weaver, M; White, R; Jobling, S; Routledge, EJ

    2013-01-01

    This article is made available through the Brunel Open Access Publishing Fund. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-No Derivative Works License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited. Estrogen receptor orthologues in molluscs may be targets for endocrine disruptors, although mechanistic evidence is lacking. Molluscs ...

  17. Analysis of 3D models of octopus estrogen receptor with estradiol: evidence for steric clashes that prevent estrogen binding.

    Science.gov (United States)

    Baker, Michael E; Chandsawangbhuwana, Charlie

    2007-09-28

    Relatives of the vertebrate estrogen receptor (ER) are found in Aplysia californica, Octopus vulgaris, Thais clavigera, and Marisa cornuarietis. Unlike vertebrate ERs, invertebrate ERs are constitutively active and do not bind estradiol. To investigate the molecular basis of the absence of estrogen binding, we constructed a 3D model of the putative steroid-binding domain on octopus ER. Our 3D model indicates that binding of estradiol to octopus ER is prevented by steric clashes between estradiol and amino acids in the steroid-binding pocket. In this respect, octopus ER resembles vertebrate estrogen-related receptors (ERR), which have a ligand-binding pocket that cannot accommodate estradiol. Like ERR, octopus ER also may have the activation function 2 domain (AF2) in a configuration that can bind to coactivators in the absence of estrogens, which would explain constitutive activity of octopus ER.

  18. Estrogen-dependent changes in serum iron levels as a translator of the adverse effects of estrogen during infection: a conceptual framework.

    Science.gov (United States)

    Hamad, Mawieh; Awadallah, Samir

    2013-12-01

    Elevated levels of estrogen often associate with increased susceptibility to infection. This has been attributed to the ability of estrogen to concomitantly enhance the growth and virulence of pathogens and suppress host immunity. But the exact mechanism of how estrogen mediates such effects, especially in cases where the pathogen and/or the immune components in question do not express estrogen receptors, has yet to be elucidated. Here we propose that translating the adverse effects of estrogen during infection is dependent to a significant degree upon its ability to manipulate iron homeostasis. For elevated levels of estrogen alter the synthesis and/or activity of several factors involved in iron metabolism including hypoxia inducible factor 1α (HIF-1α) and hepcidin among others. This leads to the inhibition of hepcidin synthesis in hepatocytes and the maintenance of ferroportin (FPN) integrity on the surface of iron-releasing duodenal enterocytes, hepatocytes, and macrophages. Intact FPN permits the continuous efflux of dietary and stored iron into the circulation, which further enhances pathogen growth and virulence on the one hand and suppresses host immunity on the other. This new conceptual framework may help explain a multitude of disparate clinical and experimental observations pertinent to the relationship between estrogen and infection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Estradiol-induced estrogen receptor-alpha trafficking.

    Science.gov (United States)

    Bondar, Galyna; Kuo, John; Hamid, Naheed; Micevych, Paul

    2009-12-02

    Estradiol has rapid actions in the CNS that are mediated by membrane estrogen receptors (ERs) and activate cell signaling pathways through interaction with metabotropic glutamate receptors (mGluRs). Membrane-initiated estradiol signaling increases the free cytoplasmic calcium concentration ([Ca(2+)](i)) that stimulates the synthesis of neuroprogesterone in astrocytes. We used surface biotinylation to demonstrate that ERalpha has an extracellular portion. In addition to the full-length ERalpha [apparent molecular weight (MW), 66 kDa], surface biotinylation labeled an ERalpha-immunoreactive protein (MW, approximately 52 kDa) identified by both COOH- and NH(2)-directed antibodies. Estradiol treatment regulated membrane levels of both proteins in parallel: within 5 min, estradiol significantly increased membrane levels of the 66 and 52 kDa ERalpha. Internalization, a measure of membrane receptor activation, was also increased by estradiol with a similar time course. Continuous treatment with estradiol for 24-48 h reduced ERalpha levels, suggesting receptor downregulation. Estradiol also increased mGluR1a trafficking and internalization, consistent with the proposed ERalpha-mGluR1a interaction. Blocking ER with ICI 182,780 or mGluR1a with LY 367385 prevented ERalpha trafficking to and from the membrane. Estradiol-induced [Ca(2+)](i) flux was also significantly increased at the time of peak ERalpha activation/internalization. These results demonstrate that ERalpha is present in the membrane and has an extracellular portion. Furthermore, membrane levels and internalization of ERalpha are regulated by estradiol and mGluR1a ligands. The pattern of trafficking into and out of the membrane suggests that the changing concentration of estradiol during the estrous cycle regulates ERalpha to augment and then terminate membrane-initiated signaling.

  20. Estradiol-induced estrogen receptor-α trafficking

    Science.gov (United States)

    Bondar, Galyna; Kuo, John; Hamid, Naheed; Micevych, Paul

    2010-01-01

    Estradiol has rapid actions in the central nervous system, which are mediated by membrane estrogen receptors (ERs) and activate cell signaling pathways through interaction with metabotropic glutamate receptors (mGluRs). Membrane-initiated estradiol signaling increases the free cytoplasmic calcium concentration ([Ca2+]i) that stimulates the synthesis of neuroprogesterone in astrocytes. We used surface biotinylation to demonstrate that ERα has an extracellular portion. In addition to the full length ERα (apparent M.W. 66 kDa), surface biotinylation labeled an ERα-immunoreactive protein (M.W. ~ 52 kDa) identified by both COOH- and NH2-directed antibodies. Estradiol treatment regulated membrane levels of both proteins in parallel: within 5 min, estradiol significantly increased membrane levels of the 66 kDa and 52 kDa ERα. Internalization, a measure of membrane receptor activation, was also increased by estradiol with a similar time course. Continuous treatment with estradiol for 24–48 hr reduced ERα levels, suggesting receptor down-regulation. Estradiol also increased mGluR1a trafficking and internalization, consistent with the proposed ERα-mGluR1a interaction. Blocking ER with ICI 182,780 or mGluR1a with LY 367385 prevented ERα trafficking to and from the membrane. Estradiol-induced [Ca2+]i flux was also significantly increased at the time of peak ERα activation/internalization. These results demonstrate that ERα is present in the membrane and has an extracellular portion. Furthermore, membrane levels and internalization of ERα are regulated by estradiol and mGluR1a ligands. The pattern of trafficking into and out of the membrane suggests that the changing concentration of estradiol during the estrous cycle regulates ERα to augment and then terminate membrane-initiated signaling. PMID:19955385

  1. Effects of gamma irradiation on the DNA-protein complex between the estrogen response element and the estrogen receptor

    Energy Technology Data Exchange (ETDEWEB)

    Stisova, Viktorie [Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlarce 39/64, 18086 Praha 8 (Czech Republic); Goffinont, Stephane; Spotheim-Maurizot, Melanie [Centre de Biophysique Moleculaire CNRS, rue Charles Sadron, 45071 Orleans Cedex 2 (France); Davidkova, Marie, E-mail: davidkova@ujf.cas.c [Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlarce 39/64, 18086 Praha 8 (Czech Republic)

    2010-08-15

    Signaling by estrogens, risk factors in breast cancer, is mediated through their binding to the estrogen receptor protein (ER), followed by the formation of a complex between ER and a DNA sequence, called estrogen response element (ERE). Anti-estrogens act as competitive inhibitors by blocking the signal transduction. We have studied in vitro the radiosensitivity of the complex between ERalpha, a subtype of this receptor, and a DNA fragment bearing ERE, as well as the influence of an estrogen (estradiol) or an anti-estrogen (tamoxifen) on this radiosensitivity. We observe that the complex is destabilized upon irradiation with gamma rays in aerated aqueous solution. The analysis of the decrease of binding abilities of the two partners shows that destabilization is mainly due to the damage to the protein. The destabilization is reduced when irradiating in presence of tamoxifen and is increased in presence of estradiol. These effects are due to opposite influences of the ligands on the loss of binding ability of ER. The mechanism that can account for our results is: binding of estradiol or tamoxifen induces distinct structural changes of the ER ligand-binding domain that can trigger (by allostery) distinct structural changes of the ER DNA-binding domains and thus, can differently affect ER-ERE interaction.

  2. Endoxifen, 4-Hydroxytamoxifen and an Estrogenic Derivative Modulate Estrogen Receptor Complex Mediated Apoptosis in Breast Cancer.

    Science.gov (United States)

    Maximov, Philipp Y; Abderrahman, Balkees; Fanning, Sean W; Sengupta, Surojeet; Fan, Ping; Curpan, Ramona F; Quintana Rincon, Daniela Maria; Greenland, Jeffery A; Rajan, Shyamala S; Greene, Geoffrey L; Jordan, V Craig

    2018-05-08

    Estrogen therapy was used to treat advanced breast cancer in postmenopausal women for decades until the introduction of tamoxifen. Resistance to long-term estrogen deprivation (LTED) with tamoxifen and aromatase inhibitors used as a treatment for breast cancer inevitably occurs, but unexpectedly low dose estrogen can cause regression of breast cancer and increase disease free survival in some patients. This therapeutic effect is attributed to estrogen-induced apoptosis in LTED breast cancer. Here we describe modulation of the estrogen receptor liganded with antiestrogens (endoxifen, 4-hydroxytamoxifen) and an estrogenic triphenylethylene (TPE) EthoxyTPE (EtOXTPE) on estrogen-induced apoptosis in LTED breast cancer cells. Our results show that the angular TPE estrogen (EtOXTPE) is able to induce the ER-mediated apoptosis only at a later time compared to planar estradiol in these cells. Using RT-PCR, ChIP, Western blotting, molecular modelling and X-ray crystallography techniques we report novel conformations of the ER complex with an angular estrogen EtOXTPE and endoxifen. We propose that alteration of the conformation of the ER complexes, with changes in coactivator binding, governs estrogen-induced apoptosis through the PERK sensor system to trigger an Unfolded Protein Response (UPR). The American Society for Pharmacology and Experimental Therapeutics.

  3. Flow cytometric measurement of DNA level and steroid hormone receptor assay in breast cancer

    International Nuclear Information System (INIS)

    Zubrikhina, G.N.; Kuz'mina, Eh.V.; Bassalyk, L.S.; Murav'eva, N.I.

    1989-01-01

    DNA level measured by flow cytometry and estrogen and progesteron receptors assayed in tissue samples obtained from 85 malignant and 16 benign lesions of the breast. All the benign tumors revealed 2c DNA content and most of them were receptor-negative, while 74.1% of breast carcinomas displayed aneuploidy. Three patients (3.5%) had two lines of aneuploid cells. Many aneuploid tumors were receptor-negative. Preoperative radiation treatmet (14-20 Gy) did not significantly influence the level of steroid hormone receptors in tumors. Estrogen receptor level was higher in menopausal patients than in premenopausal ones

  4. Selective estrogen receptor modulators and risk for coronary heart disease.

    Science.gov (United States)

    Cano, A; Hermenegildo, C; Oviedo, P; Tarín, J J

    2007-04-01

    Coronary heart disease (CHD) is the leading cause of death in women in most countries. Atherosclerosis is the main biological process determining CHD. Clinical data support the notion that CHD is sensitive to estrogens, but debate exists concerning the effects of the hormone on atherosclerosis and its complications. Selective estrogen receptor modulators (SERMs) are compounds capable of binding the estrogen receptor to induce a functional profile distinct from estrogens. The possibility that SERMs may shift the estrogenic balance on cardiovascular risk towards a more beneficial profile has generated interest in recent years. There is considerable information on the effects of SERMs on distinct areas that are crucial in atherogenesis. The complexity derived from the diversity of variables affecting their mechanism of action plus the differences between compounds make it difficult to delineate one uniform trend for SERMs. The present picture, nonetheless, is one where SERMs seem less powerful than estrogens in atherosclerosis protection, but more gentle with advanced forms of the disease. The recent publication of the Raloxifene Use for The Heart (RUTH) study has confirmed a neutral effect for raloxifene. Prothrombotic states may favor occlusive thrombi at sites occupied by atheromatous plaques. Platelet activation has received attention as an important determinant of arterial thrombogenesis. Although still sparse, available evidence globally suggests neutral or beneficial effects for SERMs.

  5. Estrogen-related receptor α is essential for the expression of antioxidant protection genes and mitochondrial function

    International Nuclear Information System (INIS)

    Rangwala, Shamina M.; Li, Xiaoyan; Lindsley, Loren; Wang, Xiaomei; Shaughnessy, Stacey; Daniels, Thomas G.; Szustakowski, Joseph; Nirmala, N.R.; Wu, Zhidan; Stevenson, Susan C.

    2007-01-01

    Estrogen-related receptor α (ERRα) is an important mediator of mitochondrial biogenesis and function. To investigate the transcriptional network controlling these phenomena, we investigated mitochondrial gene expression in embryonic fibroblasts isolated from ERRα null mice. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) stimulated mitochondrial gene expression program in control cells, but not in the ERRα null cells. Interestingly, the induction of levels of mitochondrial oxidative stress protection genes in response to increased PGC-1α levels was dependent on ERRα. Furthermore, we found that the PGC-1α-mediated induction of estrogen-related receptor γ and nuclear respiratory factor 2 (NRF-2), was dependent on the presence of ERRα. Basal levels of NRF-2 were decreased in the absence of ERRα. The absence of ERRα resulted in a decrease in citrate synthase enzyme activity in response to PGC-1α overexpression. Our results indicate an essential role for ERRα as a key regulator of oxidative metabolism

  6. Identifying a Mechanism for Crosstalk Between the Estrogen and Glucocorticoid Receptors | Center for Cancer Research

    Science.gov (United States)

    Estrogen has long been known to play important roles in the development and progression of breast cancer. Its receptor (ER), a member of the steroid receptor family, binds to estrogen response elements (EREs) in DNA and regulates gene transcription. More recently, another steroid receptor family member, the glucocorticoid receptor (GR), has been implicated in breast cancer

  7. Multiple estrogen receptor subtypes influence ingestive behavior in female rodents.

    Science.gov (United States)

    Santollo, Jessica; Daniels, Derek

    2015-12-01

    Postmenopausal women are at an increased risk of obesity and cardiovascular-related diseases. This is attributable, at least in part, to loss of the ovarian hormone estradiol, which inhibits food and fluid intake in humans and laboratory animal models. Although the hypophagic and anti-dipsogenic effects of estradiol have been well documented for decades, the precise mechanisms underlying these effects are not fully understood. An obvious step toward addressing this open question is identifying which estrogen receptor subtypes are involved and what intracellular processes are involved. This question, however, is complicated not only by the variety of estrogen receptor subtypes that exist, but also because many subtypes have multiple locations of action (i.e. in the nucleus or in the plasma membrane). This review will highlight our current understanding of the roles that specific estrogen receptor subtypes play in mediating estradiol's anorexigenic and anti-dipsogenic effects along with highlighting the many open questions that remain. This review will also describe recent work being performed by our laboratory aimed at answering these open questions. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Expression pattern of G protein‑coupled estrogen receptor 1 (GPER) in human cumulus granulosa cells (CGCs) of patients with PCOS.

    Science.gov (United States)

    Zang, Lili; Zhang, Quan; Zhou, Yi; Zhao, Yan; Lu, Linlin; Jiang, Zhou; Peng, Zhen; Zou, Shuhua

    2016-06-01

    Estradiol mediates its actions by binding to classical nuclear receptors, estrogen receptor α (ER-α) and estrogen receptor β (ER-β), and the non-classical G protein-coupled estrogen receptor 1(GPER). Several gene knockdown models have shown the importance of the receptors for growth of the oocyte and for ovulation. The aim of our study was to identify the pattern of GPER expression in human cumulus granulosa cells (CGCs) from ovarian follicles at different stages of oocyte maturation, and the differences of GPER expression between polycystic ovary syndrome (PCOS) patients and non-PCOS women. Thirty-eight cases of PCOS patients and a control group of thirty-two infertile women without PCOS were used in this study. GPER's location in CGCs was investigated by immunohistochemistry. Quantitative RT-PCR and western blot were used to identify the quantify GPER expression. Here we demonstrated that GPER was expressed in CGCs of both PCOS patients and non-PCOS women, and the expression of GPER was decreased significantly during oocyte maturation. But the expression levels of GPER in CGCs of PCOS patients and non-PCOS women were not significantly different. The data indicate that GPER may play a role during human oocyte maturation through its action in cumulus granulosa cells. AMHRIIs: anti-Mullerian hormone type II receptors; BMI: body mass index; CGCs: cumulus granulosa cells; COH: controlled ovarian hyperstimulation; E2: estradiol; EGFR: epidermal growth factor receptor; ER-α: estrogen receptor; ER-β: estrogen receptor β; FF: follicular fluid; FSH: follicle-stimulating hormone; GCs: granulosa cells; GPER: G protein-coupled estrogen receptor 1; GV: germinal vesicle; GVBD: germinal vesicle breakdown; HCG: human chorionic gonadotropin; IRS: immunoreactive score; IVF-ET: in vitro fertilization and embryo transfer; MI: metaphase I; MII: metaphase II; MAPK: mitogen-activated protein kinase; OCCCs: oocyte corona cumulus complexes; PCOS: polycystic ovarian syndrome; q

  9. Ligand-independent recruitment of steroid receptor coactivators to estrogen receptor by cyclin D1

    NARCIS (Netherlands)

    Zwijsen, R.M.L.; Buckle, R.S.; Hijmans, E.M.; Loomans, C.J.M.; Bernards, R.A.

    1998-01-01

    The estrogen receptor (ER) is an important regulator of growth and differentiation of breast epithelium. Transactivation by ER depends on a leucine-rich motif, which constitutes a ligand-regulated binding site for steroid receptor coactivators (SRCs). Cyclin D1 is frequently amplified in breast

  10. Estrogen-mediated hemangioma-derived stem cells through estrogen receptor-α for infantile hemangioma

    Directory of Open Access Journals (Sweden)

    Zhang L

    2017-07-01

    Full Text Available Ling Zhang,1 Hai Wei Wu,1 Weien Yuan,2 Jia Wei Zheng1 1Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Center for Specialty Strategy Research of Shanghai Jiao Tong University China Hospital Development Institute, 2School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People’s Republic of China Background: Infantile hemangiomas (IHs are the most common benign vascular tumor of infancy. They occur more frequently in female infants. The cause of hemangioma is currently unknown; however, current studies suggested the importance of estrogen (E2 signaling in hemangioma proliferation. Methods: Hemangioma-derived stem cells (HemSCs were cultured with estrogen for 48–72 h; the cell viability and proliferation were evaluated with the messenger RNA (mRNA and protein expression levels of fibroblast growth factor 2 (FGF2, vascular endothelial growth factor-A (VEGF-A and estrogen receptor-α (ER-α, by application of several in vitro assays, such as methyl thiazolyl tetrazolium (MTT, reverse transcriptase–polymerase chain reaction (RT-PCR, real-time PCR, enzyme-linked immunosorbent assay (ELISA and Western blotting. Also, the cell population’s response to external estrogen was investigated by in vivo experiments. HemSCs and human umbilical vein endothelial cells (HUVECs were mixed and injected subcutaneously into 20 flank of BALB/c-nu mice, which were randomly divided into 5 groups based on different E2 treatment doses (0, 0.01, 0.1 and 1 mg, respectively, 0.1 mg dimethyl sulfoxide (DMSO as control. Each group of mice were treated intramuscularly every week, then 2 and 4 weeks later, the subcutaneous implants were harvested and evaluated the tumor tissues with microvessel density (MVD assay and immunohistochemistry. Results: The study demonstrated that application of E2 increased the expression of FGF2, VEGF-A, and ER-α in HemSCs with the optimal concentration from 10−9 to 10−5 M. Two

  11. Preliminary Molecular Dynamic Simulations of the Estrogen Receptor Alpha Ligand Binding Domain from Antagonist to Apo

    Directory of Open Access Journals (Sweden)

    Adrian E. Roitberg

    2008-06-01

    Full Text Available Estrogen receptors (ER are known as nuclear receptors. They exist in the cytoplasm of human cells and serves as a DNA binding transcription factor that regulates gene expression. However the estrogen receptor also has additional functions independent of DNA binding. The human estrogen receptor comes in two forms, alpha and beta. This work focuses on the alpha form of the estrogen receptor. The ERα is found in breast cancer cells, ovarian stroma cells, endometrium, and the hypothalamus. It has been suggested that exposure to DDE, a metabolite of DDT, and other pesticides causes conformational changes in the estrogen receptor. Before examining these factors, this work examines the protein unfolding from the antagonist form found in the 3ERT PDB crystal structure. The 3ERT PDB crystal structure has the estrogen receptor bound to the cancer drug 4-hydroxytamoxifen. The 4-hydroxytamoxifen ligand was extracted before the simulation, resulting in new conformational freedom due to absence of van der Waals contacts between the ligand and the receptor. The conformational changes that result expose the binding clef of the co peptide beside Helix 12 of the receptor forming an apo conformation. Two key conformations in the loops at either end of the H12 are produced resulting in the antagonist to apo conformation transformation. The results were produced over a 42ns Molecular Dynamics simulation using the AMBER FF99SB force field.

  12. Effects of environmental estrogenic chemicals on AP1 mediated transcription with estrogen receptors alpha and beta.

    Science.gov (United States)

    Fujimoto, Nariaki; Honda, Hiroaki; Kitamura, Shigeyuki

    2004-01-01

    There has been much discussion concerning endocrine disrupting chemicals suspected of exerting adverse effects in both wildlife and humans. Since the majority of these compounds are estrogenic, a large number of in vitro tests for estrogenic characteristics have been developed for screening purpose. One reliable and widely used method is the reporter gene assay employing estrogen receptors (ERs) and a reporter gene with a cis-acting estrogen responsive element (ERE). Other elements such as AP1 also mediate estrogenic signals and the manner of response could be quite different from that of ERE. Since this has yet to be explored, the ER mediated AP1 activity in response to a series of environmental estrogens was investigated in comparison with ERE findings. All the compounds exhibited estrogenic properties with ERE-luc and their AP1 responses were quite similar. These was one exception, however, p,p'-DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane) did not exert any AP1-luc activity, while it appeared to be estrogenic at 10(-7) to 10(-5)M with the ERE action. None of the compounds demonstrated ER beta:AP1 activity. These data suggest that significant differences can occur in responses through the two estrogen pathways depending on environmental chemicals.

  13. Expression of androgen and estrogen receptors in the testicular ...

    African Journals Online (AJOL)

    enoh

    2012-04-10

    Apr 10, 2012 ... 66: 1161-1168. Oliveira CA, Mahecha GA, Carnes K, Prins GS, Saunders PT, Franca. LR, Hess RA (2004). Differential hormonal regulation of estrogen receptors ERα and ER and androgen receptor expression in rat efferent ductules. Reproduction, 128(1): 73-86. O'Shaughnessy PJ, Johnston H, Willerton L ...

  14. Vitamin D receptor and estrogen receptor gene polymorphisms in postmenopausal Danish women

    DEFF Research Database (Denmark)

    Bagger, Y Z; Hassager, C; Heegaard, Anne-Marie

    2000-01-01

    To investigate the polymorphisms of the vitamin D receptor (VDR) and estrogen receptor (ER) genes in relation to biochemical markers of bone turnover (serum osteocalcin and urinary collagen type I degradation products (CrossLaps), and to study ER genotypes in relation to serum lipoproteins, blood...... pressure, or changes in these parameters after 2 years of hormone replacement therapy (HRT) in 499 Danish postmenopausal women....

  15. The selective estrogen receptor modulators in breast cancer prevention.

    Science.gov (United States)

    Li, Fangxuan; Dou, Jinli; Wei, Lijuan; Li, Shixia; Liu, Juntian

    2016-05-01

    Persistently increased blood levels of estrogens are associated with an increased risk of breast cancer. Selective estrogen receptor modulators (SERMs) are a class of compounds that act on the estrogen receptor (ER). Several clinical trials have demonstrated the effectiveness of its prophylactic administration. Incidence of invasive ER-positive breast cancer was reduced by SERMs treatment, especially for those women with high risk of developing breast cancer. In this study, we reviewed the clinical application of SERMs in breast cancer prevention. To date, four prospective randomized clinical trials had been performed to test the efficacy of tamoxifen for this purpose. Concerning on the benefit and cost of tamoxifen, various studies from different countries demonstrated that chemoprevention with tamoxifen seemed to be cost-effective for women with a high risk of invasive breast cancer. Based above, tamoxifen was approved for breast cancer prevention by the US Food and Drug Administration in 1998. Raloxifene was also approved for postmenopausal women in 2007 for breast cancer prevention which reduces the risk of invasive breast cancer with a lower risk of unwanted stimulation of endometrium. Thus, raloxifene is considered to have a better clinical possesses as prophylactic agent. Several other agents, such as arzoxifene and lasofoxifene, are currently being investigated in clinic. The American Society of Clinical Oncology and National Comprehensive Cancer Network had published guidelines on breast cancer chemoprevention by SERMs. However, use of tamoxifen and raloxifene for primary breast cancer prevention was still low. A broader educational effort is needed to alert women and primary care physicians that SERMs are available to reduce breast cancer risk.

  16. Immune-Specific Expression and Estrogenic Regulation of the Four Estrogen Receptor Isoforms in Female Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Ayako Casanova-Nakayama

    2018-03-01

    Full Text Available Genomic actions of estrogens in vertebrates are exerted via two intracellular estrogen receptor (ER subtypes, ERα and ERβ, which show cell- and tissue-specific expression profiles. Mammalian immune cells express ERs and are responsive to estrogens. More recently, evidence became available that ERs are also present in the immune organs and cells of teleost fish, suggesting that the immunomodulatory function of estrogens has been conserved throughout vertebrate evolution. For a better understanding of the sensitivity and the responsiveness of the fish immune system to estrogens, more insight is needed on the abundance of ERs in the fish immune system, the cellular ratios of the ER subtypes, and their autoregulation by estrogens. Consequently, the aims of the present study were (i to determine the absolute mRNA copy numbers of the four ER isoforms in the immune organs and cells of rainbow trout, Oncorhynchus mykiss, and to compare them to the hepatic ER numbers; (ii to analyse the ER mRNA isoform ratios in the immune system; and, (iii finally, to examine the alterations of immune ER mRNA expression levels in sexually immature trout exposed to 17β-estradiol (E2, as well as the alterations of immune ER mRNA expression levels in sexually mature trout during the reproductive cycle. All four ER isoforms were present in immune organs—head kidney, spleen-and immune cells from head kidney and blood of rainbow trout, but their mRNA levels were substantially lower than in the liver. The ER isoform ratios were tissue- and cell-specific, both within the immune system, but also between the immune system and the liver. Short-term administration of E2 to juvenile female trout altered the ER mRNA levels in the liver, but the ERs of the immune organs and cells were not responsive. Changes of ER gene transcript numbers in immune organs and cells occurred during the reproductive cycle of mature female trout, but the changes in the immune ER profiles differed

  17. The role of selective estrogen receptor modulators in the treatment of schizophrenia.

    Science.gov (United States)

    Bratek, Agnieszka; Krysta, Krzysztof; Drzyzga, Karolina; Barańska, Justyna; Kucia, Krzysztof

    2016-09-01

    Gender differences in schizophrenia have been recognized for a long time and it has been widely accepted that sex steroid hormones, especially estradiol, are strongly attributed to this fact. Two hypotheses regarding estradiol action in psychoses gained special research attention - the estrogen protection hypothesis and hypoestrogenism hypothesis. A growing number of studies have shown benefits in augmenting antipsychotic treatment with estrogens or selective estrogen receptor modulators (SERM). This review is focused on the role of selective estrogen receptor modulators in the treatment of schizophrenic patients. In order to achieve this result PubMed was searched using the following terms: schizophrenia, raloxifene, humans. We reviewed only randomized, placebo-controlled studies. Raloxifene, a selective estrogen receptor modulator was identified as useful to improve negative, positive, and general psychopathological symptoms, and also cognitive functions. All reviewed studies indicated improvement in at least one studied domain. Augmentation with raloxifene was found to be a beneficial treatment strategy for chronic schizophrenia both in female and male patients, however potential side effects (a small increase in the risk of venous thromboembolism and endometrial cancer) should be carefully considered. SERMs could be an effective augmentation strategy in the treatment of both men women with schizophrenia, although further research efforts are needed to study potential long-term side effects.

  18. The regulation of MS-KIF18A expression and cross talk with estrogen receptor.

    Directory of Open Access Journals (Sweden)

    Margalit Zusev

    2009-07-01

    Full Text Available This study provides a novel view on the interactions between the MS-KIF18A, a kinesin protein, and estrogen receptor alpha (ERalpha which were studied in vivo and in vitro. Additionally, the regulation of MS-KIF18A expression by estrogen was investigated at the gene and protein levels. An association between recombinant proteins; ERalpha and MS-KIF18A was demonstrated in vitro in a pull down assay. Such interactions were proven also for endogenous proteins in MBA-15 cells were detected prominently in the cytoplasm and are up-regulated by estrogen. Additionally, an association between these proteins and the transcription factor NF-kappaB was identified. MS-KIF18A mRNA expression was measured in vivo in relation to age and estrogen level in mice and rats models. A decrease in MS-KIF18A mRNA level was measured in old and in OVX-estrogen depleted rats as compared to young animals. The low MS-KIF18A mRNA expression in OVX rats was restored by estrogen treatment. We studied the regulation of MS-KIF18A transcription by estrogen using the luciferase reporter gene and chromatin immuno-precipitation (ChIP assays. The luciferase reporter gene assay demonstrated an increase in MS-KIF18A promoter activity in response to 10(-8 M estrogen and 10(-7M ICI-182,780. Complimentary, the ChIP assay quantified the binding of ERalpha and pcJun to the MS-KIF18A promoter that was enhanced in cells treated by estrogen and ICI-182,780. In addition, cells treated by estrogen expressed higher levels of MS-KIF18A mRNA and protein and the protein turnover in MBA-15 cells was accelerated. Presented data demonstrated that ERalpha is a defined cargo of MS-KIF18A and added novel insight on the role of estrogen in regulation of MS-KIF18A expression both in vivo and in vitro.

  19. Selectivity of natural, synthetic and environmental estrogens for zebrafish estrogen receptors

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Caroline [Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5056 (United States); Grimaldi, Marina; Boulahtouf, Abdelhay [Institut de Recherche en Cancérologie de Montpellier, Institut National de la Santé de la Recherche Médicale U896, Institut Régional de Cancérologie de Montpellier, Université Montpellier 1, 34298 Montpellier (France); Pakdel, Farzad [Institut de Recherche sur la Santé, Environnement et Travail (IRSET), INSERM U1085, Université de Rennes 1, Rennes (France); Brion, François; Aït-Aïssa, Sélim [Unité Écotoxicologie In Vitro et In Vivo, INERIS, Parc ALATA, 60550 Verneuil-en-Halatte (France); Cavaillès, Vincent [Institut de Recherche en Cancérologie de Montpellier, Institut National de la Santé de la Recherche Médicale U896, Institut Régional de Cancérologie de Montpellier, Université Montpellier 1, 34298 Montpellier (France); Bourguet, William [U1054, Centre de Biochimie Structurale, CNRS UMR5048, Université Montpellier 1 et 2, 34290 Montpellier (France); Gustafsson, Jan-Ake [Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5056 (United States); Department of Biosciences and Nutrition, Karolinska Institutet, 14183 Huddinge (Sweden); and others

    2014-10-01

    Zebrafish, Danio rerio, is increasingly used as an animal model to study the effects of pharmaceuticals and environmental estrogens. As most of these estrogens have only been tested on human estrogen receptors (ERs), it is necessary to measure their effects on zebrafish ERs. In humans there are two distinct nuclear ERs (hERα and hERβ), whereas the zebrafish genome encodes three ERs, zfERα and two zfERβs (zfERβ1 and zfERβ2). In this study, we established HeLa-based reporter cell lines stably expressing each of the three zfERs. We first reported that estrogens more efficiently activate the zfERs at 28 °C as compared to 37 °C, thus reflecting the physiological temperature of zebrafish in wildlife. We then showed significant differences in the ability of agonist and antagonist estrogens to modulate activation of the three zfER isotypes in comparison to hERs. Environmental compounds (bisphenol A, alkylphenols, mycoestrogens) which are hER panagonists and hERβ selective agonists displayed greater potency for zfERα as compared to zfERβs. Among hERα selective synthetic agonists, PPT did not activate zfERα while 16α-LE2 was the most zfERα selective compound. Altogether, these results confirm that all hER ligands control in a similar manner the transcriptional activity of zfERs although significant differences in selectivity were observed among subtypes. The zfER subtype selective ligands that we identified thus represent new valuable tools to dissect the physiological roles of the different zfERs. Finally, our work also points out that care has to be taken in transposing the results obtained using the zebrafish as a model for human physiopathology. - Highlights: • Zebrafish is increasingly used to study the effects of estrogens. • We assessed the activity of pharmaceutical and environmental estrogens on zfERs. • Environmental estrogens displayed greater potency for zfERα compared to zfERβs. • hERβ selective agonists displayed greater potency for zf

  20. Quantitative RT-PCR analysis of estrogen receptor gene expression in laser microdissected prostate cancer tissue.

    Science.gov (United States)

    Walton, Thomas J; Li, Geng; McCulloch, Thomas A; Seth, Rashmi; Powe, Desmond G; Bishop, Michael C; Rees, Robert C

    2009-06-01

    Real-time quantitative RT-PCR analysis of laser microdissected tissue is considered the most accurate technique for determining tissue gene expression. The discovery of estrogen receptor beta (ERbeta) has focussed renewed interest on the role of estrogen receptors in prostate cancer, yet few studies have utilized the technique to analyze estrogen receptor gene expression in prostate cancer. Fresh tissue was obtained from 11 radical prostatectomy specimens and from 6 patients with benign prostate hyperplasia. Pure populations of benign and malignant prostate epithelium were laser microdissected, followed by RNA isolation and electrophoresis. Quantitative RT-PCR was performed using primers for androgen receptor (AR), estrogen receptor beta (ERbeta), estrogen receptor alpha (ERalpha), progesterone receptor (PGR) and prostate specific antigen (PSA), with normalization to two housekeeping genes. Differences in gene expression were analyzed using the Mann-Whitney U-test. Correlation coefficients were analyzed using Spearman's test. Significant positive correlations were seen when AR and AR-dependent PSA, and ERalpha and ERalpha-dependent PGR were compared, indicating a representative population of RNA transcripts. ERbeta gene expression was significantly over-expressed in the cancer group compared with benign controls (P cancer group (P prostate cancer specimens. In concert with recent studies the findings suggest differential production of ERbeta splice variants, which may play important roles in the genesis of prostate cancer. (c) 2009 Wiley-Liss, Inc.

  1. Quality control of estrogen receptor assays.

    Science.gov (United States)

    Godolphin, W; Jacobson, B

    1980-01-01

    Four types of material have been used for the quality control of routine assays of estrogen receptors in human breast tumors. Pieces of hormone-dependent Nb rat mammary tumors gave a precision about 40%. Rat uteri and rat tumors pulverized at liquid nitrogen temperature and stored as powder yielded precision about 30%. Powdered and lyophilised human tumors appear the best with precision as good as 17%.

  2. Effects of gamma irradiation on the DNA-protein complex between the estrogen response element and the estrogen receptor

    Czech Academy of Sciences Publication Activity Database

    Štísová, Viktorie; Goffinont, S.; Maurizot, M. S.; Davídková, Marie

    2010-01-01

    Roč. 79, č. 8 (2010), s. 880-889 ISSN 0969-806X R&D Projects: GA MŠk 1P05OC085; GA MŠk OC09012 Institutional research plan: CEZ:AV0Z10480505 Keywords : DNA-protein complex * estrogen response element * estrogen receptor * ionizing radiation Subject RIV: BO - Biophysics Impact factor: 1.132, year: 2010

  3. Human estrogen receptor (ESR) gene locus: PssI dimorphism

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, R T; Taylor, J E; Frossard, P M [California Biotechnology Inc., Mountain View, CA (USA); Shine, J J [Garvan Institute, Darlinghurst (Australia)

    1988-07-25

    pESR-2, a 2.1 kb partial cDNA containing the entire translated sequence of the human estrogen receptor mRNA isolated from MCF-7 human breast cancer cells, was subcloned in the Eco RI site of pBR322. PssI (PuGGNCCPy) identifies a single two-allele polymorphism with bands at either 1.7 or 1.4 kb, as well as invariant bands at 12.6, 9.3, 4.1, 3.7, 2.4, 2.2, and 1.2 kb. Its frequency was studied in 77 unrelated North American Caucasians. The human estrogen receptor gene has been localized to 6q24 -- q27 by in situ hybridization. Co-dominant segregation is demonstrated in one family (8 individuals).

  4. Melanocortin 4 receptor is not required for estrogenic regulations on energy homeostasis and reproduction

    Science.gov (United States)

    Brain estrogen receptor-a (ERa) is essential for estrogenic regulation of energy homeostasis and reproduction. We previously showed that ERa expressed by pro-opiomelanocortin (POMC) neurons mediates estrogen's effects on food intake, body weight, negative regulation of hypothalamic–pituitary–gonadal...

  5. Activation of Penile Proadipogenic Peroxisome Proliferator-Activated Receptor with an Estrogen: Interaction with Estrogen Receptor Alpha during Postnatal Development

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Mansour

    2008-01-01

    Full Text Available Exposure to the estrogen receptor alpha (ER ligand diethylstilbesterol (DES between neonatal days 2 to 12 induces penile adipogenesis and adult infertility in rats. The objective of this study was to investigate the in vivo interaction between DES-activated ER and the proadipogenic transcription factor peroxisome proliferator-activated receptor gamma (PPAR. Transcripts for PPARs , , and and 1a splice variant were detected in Sprague-Dawley normal rat penis with PPAR predominating. In addition, PPAR1b and PPAR2 were newly induced by DES. The PPAR transcripts were significantly upregulated with DES and reduced by antiestrogen ICI 182, 780. At the cellular level, PPAR protein was detected in urethral transitional epithelium and stromal, endothelial, neuronal, and smooth muscular cells. Treatment with DES activated ER and induced adipocyte differentiation in corpus cavernosum penis. Those adipocytes exhibited strong nuclear PPAR expression. These results suggest a biological overlap between PPAR and ER and highlight a mechanism for endocrine disruption.

  6. Phorbol ester induced phosphorylation of the estrogen receptor in intact MCF-7 human breast cancer cells

    International Nuclear Information System (INIS)

    Knabbe, C.; Lippman, M.E.; Greene, G.L.; Dickson, R.B.

    1986-01-01

    Recent studies with a variety of cellular receptors have shown that phorbol ester induced phosphorylation modulates ligand binding and function. In this study the authors present direct evidence that the estrogen receptor in MCF-7 human breast cancer cells is a phosphoprotein whose phosphorylation state can be enhanced specifically by phorbol-12-myristate-13-acetate (PMA). Cells were cultured to 6h in the presence of [ 32 P]-orthophosphate. Whole cell extracts were immunoprecipitated with a monoclonal antibody (D58) against the estrogen receptor and subjected to SDS-polyacrylamide electrophoresis. Autoradiography showed a specific band in the region of 60-62 kDa which was significantly increased in preparations from PMA treated cells. Phospho-amino acid analysis demonstrated specific phosphorylation of serine and threonine residues. Cholera toxin or forskolin did not change the phosphorylation state of this protein. In a parallel binding analysis PMA led to a rapid decrease of estrogen binding sites. The estrogen induction of both progesterone receptors and growth in semisolid medium was blocked by PMA, whereas the estrogen induction of the 8kDa protein corresponding to the ps2 gene product and of the 52 kDa protein was not affected. In conclusion, phorbol esters can induce phosphorylation of the estrogen receptor. This process may be associated with the inactivation of certain receptor functions

  7. Estrogen receptor mRNA in mineralized tissues of rainbow trout: calcium mobilization by estrogen.

    Science.gov (United States)

    Armour, K J; Lehane, D B; Pakdel, F; Valotaire, Y; Graham, R; Russell, R G; Henderson, I W

    1997-07-07

    RT-PCR was undertaken on total RNA extracts from bone and scales of the rainbow trout, Oncorhynchus mykiss. The rainbow trout estrogen receptor (ER)-specific primers used amplified a single product of expected size from each tissue which, using Southern blotting, strongly hybridized with a 32P-labelled rtER probe under stringent conditions. These data provide the first in vivo evidence of ER mRNA in bone and scale tissues of rainbow trout and suggest that the effects of estrogen observed in this study (increased bone mineral and decreased scale mineral contents, respectively) may be mediated directly through ER.

  8. ESTROGEN RECEPTOR-alpha IMMUNOREACTIVE NEURONS IN THE BRAINSTEM AND SPINAL CORD OF THE FEMALE RHESUS MONKEY : SPECIES-SPECIFIC CHARACTERISTICS

    NARCIS (Netherlands)

    Vanderhorst, V. G. J. M.; Terasawa, E.; Ralston, H. J.

    2009-01-01

    The distribution pattern of estrogen receptors in the rodent CNS has been reported extensively, but mapping of estrogen receptors in primates is incomplete. In this study we describe the distribution of estrogen receptor alpha immunoreactive (ER-alpha 1R) neurons in the brainstem and spinal cord of

  9. Targeting estrogen/estrogen receptor alpha enhances Bacillus Calmette-Guérin efficacy in bladder cancer.

    Science.gov (United States)

    Shang, Zhiqun; Li, Yanjun; Hsu, Iawen; Zhang, Minghao; Tian, Jing; Wen, Simeng; Han, Ruifa; Messing, Edward M; Chang, Chawnshang; Niu, Yuanjie; Yeh, Shuyuan

    2016-05-10

    Recent studies showed the potential linkage of estrogen/estrogen receptor signaling with bladder tumorigenesis, yet detailed mechanisms remain elusive. Here we found a new potential therapy with the combination of Bacillus Calmette-Guerin (BCG) and the anti-estrogen ICI 182,780 led to better suppression of bladder cancer (BCa) than BCG alone. Mechanism dissection found ICI 182,780 could promote BCG attachment/internalization to the BCa cells through increased integrin-α5β1 expression and IL-6 release, which may enhance BCG-induced suppression of BCa cell growth via recruiting more monocytes/macrophages to BCa cells and increased TNF-α release. Consistently, in vivo studies found ICI 182,780 could potentiate the anti-BCa effects of BCG in the carcinogen-induced mouse BCa models. Together, these in vitro and in vivo results suggest that combining BCG with anti-estrogen may become a new therapeutic approach with better efficacy to suppress BCa progression and recurrence.

  10. Expression and function of the human estrogen receptor in yeast

    International Nuclear Information System (INIS)

    White, J.H.; Metzger, D.; Chambon, P.

    1988-01-01

    Gene expression in eukaryotes is regulated at many levels. Moreover, there is increasing evidence that the basic control mechanisms of transcription initiation have been conserved across the range of eukaryotes from yeast to man. In vertebrates, the nuclear receptors, whose activity is dependent on the binding of specific ligands, stimulate transcription by interacting with specific cis-acting sequences and display all of the hallmarks of inducible enhancer factors. Alignment of their amino acid sequences indicates that they are composed of a series of conserved domains. The domain structure of the human estrogen receptor (hER) is typical of receptor proteins. Region C, containing two putative zinc fingers, comprises the DNA-binding domain responsible for specific recognition of estrogen response elements (ERE). Region E contains the hormone-binding domain and domain(s) responsible for transcription activation. A mutant of the hER, called HE15, which lacks the hormone-binding domain, binds DNA in vivo and in vitro but activates transcription only poorly in a constitutive manner in vivo in HeLa cells. A series of studies have demonstrated that the hormone- and DNA-binding domains of the nuclear receptors function independently. Chimeric proteins consisting of the DNA-binding domain of yeast GAL4 coupled to the hormone-binding domains of either the hER or glucocorticoid receptor element (GRE) will stimulate transcription in HeLa cells when bound to a UAS. Taken together, these results demonstrate that the hER and other nuclear receptors, as well as GAL4 and GCN4 proteins of yeast, consist of discrete and separable DNA-binding and transcription-activation functions. To investigate these striking parallels further, the authors have expressed the hER in the yeast Saccharomyces cerevisiae and have analyzed its hormone- and DNA-binding properties in vitro and its ability to stimulate transcription in vivo

  11. G protein-coupled receptor 30 is an estrogen receptor in the plasma membrane

    International Nuclear Information System (INIS)

    Funakoshi, Takeshi; Yanai, Akie; Shinoda, Koh; Kawano, Michio M.; Mizukami, Yoichi

    2006-01-01

    Recently, GPR30 was reported to be a novel estrogen receptor; however, its intracellular localization has remained controversial. To investigate the intracellular localization of GPR30 in vivo, we produced four kinds of polyclonal antibodies for distinct epitopes on GPR30. Immunocytochemical observations using anti-GPR30 antibody and anti-FLAG antibody show that FLAG-GPR30 localizes to the plasma membrane 24 h after transfection. Treatment with estrogen (17β-estradiol or E2) causes an elevation in the intracellular Ca 2+ concentration ([Ca 2+ ] i ) within 10 s in HeLa cells expressing FLAG-GPR30. In addition, E2 induces the translocation of GPR30 from the plasma membrane to the cytoplasm by 1 h after stimulation. Immunohistochemical analysis shows that GPR30 exists on the cell surface of CA2 pyramidal neuronal cells. The images on transmission electron microscopy show that GPR30 is localized to a particular region associated with the plasma membranes of the pyramidal cells. These data indicate that GPR30, a transmembrane receptor for estrogen, is localized to the plasma membrane of CA2 pyramidal neuronal cells of the hippocampus in rat brain

  12. Estrogen regulates estrogen receptors and antioxidant gene expression in mouse skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Kristen A Baltgalvis

    Full Text Available BACKGROUND: Estrogens are associated with the loss of skeletal muscle strength in women with age. Ovarian hormone removal by ovariectomy in mice leads to a loss of muscle strength, which is reversed with 17beta-estradiol replacement. Aging is also associated with an increase in antioxidant stress, and estrogens can improve antioxidant status via their interaction with estrogen receptors (ER to regulate antioxidant gene expression. The purpose of this study was to determine if ER and antioxidant gene expression in skeletal muscle are responsive to changes in circulating estradiol, and if ERs regulate antioxidant gene expression in this tissue. METHODOLOGY/PRINCIPAL FINDINGS: Adult C57BL/6 mice underwent ovariectomies or sham surgeries to remove circulating estrogens. These mice were implanted with placebo or 17beta-estradiol pellets acutely or chronically. A separate experiment examined mice that received weekly injections of Faslodex to chronically block ERs. Skeletal muscles were analyzed for expression of ER genes and proteins and antioxidant genes. ERalpha was the most abundant, followed by Gper and ERbeta in both soleus and EDL muscles. The loss of estrogens through ovariectomy induced ERalpha gene and protein expression in the soleus, EDL, and TA muscles at both the acute and chronic time points. Gpx3 mRNA was also induced both acutely and chronically in all 3 muscles in mice receiving 17beta-estradiol. When ERs were blocked using Faslodex, Gpx3 mRNA was downregulated in the soleus muscle, but not the EDL and TA muscles. CONCLUSIONS/SIGNIFICANCE: These data suggest that Gpx3 and ERalpha gene expression are sensitive to circulating estrogens in skeletal muscle. ERs may regulate Gpx3 gene expression in the soleus muscle, but skeletal muscle regulation of Gpx3 via ERs is dependent upon muscle type. Further work is needed to determine the indirect effects of estrogen and ERalpha on Gpx3 expression in skeletal muscle, and their importance in the

  13. A Non-Nuclear Role of the Estrogen Receptor Alpha in the Regulation of Cell-Cell Interactions

    National Research Council Canada - National Science Library

    Darimont, Beatrice D

    2006-01-01

    .... The actions of estrogens are mediated by the estrogen receptors ERalpha and ERbeta. These hormone-regulated transcription factors translate the presence of estrogen into changes in gene expression...

  14. Transcriptomic analysis identifies gene networks regulated by estrogen receptor α (ERα) and ERβ that control distinct effects of different botanical estrogens

    Science.gov (United States)

    Gong, Ping; Madak-Erdogan, Zeynep; Li, Jilong; Cheng, Jianlin; Greenlief, C. Michael; Helferich, William G.; Katzenellenbogen, John A.

    2014-01-01

    The estrogen receptors (ERs) ERα and ERβ mediate the actions of endogenous estrogens as well as those of botanical estrogens (BEs) present in plants. BEs are ingested in the diet and also widely consumed by postmenopausal women as dietary supplements, often as a substitute for the loss of endogenous estrogens at menopause. However, their activities and efficacies, and similarities and differences in gene expression programs with respect to endogenous estrogens such as estradiol (E2) are not fully understood. Because gene expression patterns underlie and control the broad physiological effects of estrogens, we have investigated and compared the gene networks that are regulated by different BEs and by E2. Our aim was to determine if the soy and licorice BEs control similar or different gene expression programs and to compare their gene regulations with that of E2. Gene expression was examined by RNA-Seq in human breast cancer (MCF7) cells treated with control vehicle, BE or E2. These cells contained three different complements of ERs, ERα only, ERα+ERβ, or ERβ only, reflecting the different ratios of these two receptors in different human breast cancers and in different estrogen target cells. Using principal component, hierarchical clustering, and gene ontology and interactome analyses, we found that BEs regulated many of the same genes as did E2. The genes regulated by each BE, however, were somewhat different from one another, with some genes being regulated uniquely by each compound. The overlap with E2 in regulated genes was greatest for the soy isoflavones genistein and S-equol, while the greatest difference from E2 in gene expression pattern was observed for the licorice root BE liquiritigenin. The gene expression pattern of each ligand depended greatly on the cell background of ERs present. Despite similarities in gene expression pattern with E2, the BEs were generally less stimulatory of genes promoting proliferation and were more pro-apoptotic in their

  15. Does signaling of estrogen-related receptors affect structure and function of bank vole Leydig cells?

    Science.gov (United States)

    Pawlicki, P; Milon, A; Zarzycka, M; Galas, J; Tworzydlo, W; Kaminska, A; Pardyak, L; Lesniak, K; Pacwa, A; Bilinska, B; Gorowska-Wojtowicz, E; Kotula-Balak, M

    2017-06-01

    To get a deeper insight into the function of estrogen-related receptors (ERRs) and dissect underlying mechanism in Leydig cells, ERRs (type α, β and γ) were blocked or activated in testes of adult bank voles (Myodes glareolus) which show seasonal changes in the intratesticular sex hormones level. Both actively reproducing animals (long day conditions; LD) and those with regression of the reproductive system (short day conditions; SD) received intraperitoneal injections of selective ERRα antagonist 3-[4-(2,4-Bis-trifluoromethylbenzyloxy)-3-methoxyphenyl]-2-cyano-N-(5-trifluoromethyl-1,3,4-thiadiazol-2-yl)acrylamide (XCT 790) or selective ERRβ/ERRγ agonist N-(4-(Diethylaminobenzylidenyl)-N'-(4-hydroxybenzoyl)-hydrazine (DY131) (50 μ/kg bw; six doses every other day). Markedly more, XCT 790 (P endogenous estrogen level in treated males. Notably, immunolocalization of ERRs and above proteins, exclusively in Leydig cells, indicated their involvement in Leydig cell function control based on interactions with endogenous estrogen level and/or estrogen signaling via ERRs. Treatment with XCT 790 or DY131 significantly decreased (P endogenous estrogen status in the testis. Further understanding of mechanism(s) by which individual types of ERRs can control Leydig cell function is relevant for predicting and preventing steroidogenic and spermatogenic disorders.

  16. Letrozole induced low estrogen levels affected the expressions of duodenal and renal calcium-processing gene in laying hens.

    Science.gov (United States)

    Li, Qiao; Zhao, Xingkai; Wang, Shujie; Zhou, Zhenlei

    2018-01-01

    Estrogen regulates the calcium homeostasis in hens, but the mechanisms involved are still unclear fully. In this study, we investigated whether letrozole (LZ) induced low estrogen levels affected the calcium absorption and transport in layers. In the duodenum, we observed a significant decrease of mRNA expressions of Calbindin-28k (CaBP-28k) and plasma membrane Ca 2+ -ATPase (PMCA 1b) while CaBP-28k protein expression was declined in birds with LZ treatment, and the mRNA levels of duodenal transient receptor potential vanilloid 6 (TRPV6) and Na + /Ca 2+ exchanger 1 (NCX1) were not affected. Interestingly, we observed the different changes in the kidney. The renal mRNA expressions of TRPV6 and NCX1 were unregulated while the PMCA1b was down-regulated in low estrogen layers, however, the CaBP-28k gene and protein expressions were no changed in the kidney. Furthermore, it showed that the duodenal estradiol receptor 2 (ESR2) transcripts rather than parathyroid hormone 1 receptor (PTH1R) and calcitonin receptor (CALCR) played key roles to down-regulate calcium transport in LZ-treated birds. In conclusion, CaBP-28k, PMCA 1b and ESR2 genes in the duodenum may be primary targets for estrogen regulation in order to control calcium homeostasis in hens. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Expression of Estrogen Receptor Alpha in Malignant Melanoma

    Directory of Open Access Journals (Sweden)

    Parvin Rajabi

    2017-01-01

    Full Text Available Background: Features of malignant melanoma (MM vary in the different geographic regions of the world. This may be attributable to environmental, ethnic, and genetic factors. The aim of this study was to determine the expression of estrogen receptor alpha (ER-α in MM in Isfahan, Iran. Materials and Methods: This study was planned as a descriptive, analytical, cross-sectional investigation. During this study, paraffin-embedded tissue blocks of patients with a histopathologic diagnosis of MM was studied for ER-α using immunohistochemistry (IHC. Results: In this study, 38 patients (female/male; 20/18 with a definite diagnosis of malignant cutaneous melanoma and mean age of 52.4 ± 11.2 years were investigated. Using envision IHC staining, there were not any cases with ER-α expression. Conclusion: In confirmation to the most previous studies, expression of ER-α was negative in MM. It is recommended to investigate the expression of estrogen receptor beta and other markers in MM.

  18. Immunohistochemical Expression of Estrogen and Progesterone Receptors in Epulis Fissuratum

    Directory of Open Access Journals (Sweden)

    Maryam Seyedmajidi

    2013-01-01

    Full Text Available Background: Epulis Fissuratum (Epulis Fissuratum (EF or Denture Epulis or inflammatory fibrous hyperplasia is a common hyperplastic tumor-like lesion with reactive nature, related to loose and ill-fitting, full or partial removable dentures and it is more common in women than men. For this reason, hormonal influences may also play role in its creation. The effect of steroid hormones especially sex hormones (Estrogen and progesterone on oral mucosa is identified in some studies. In the present study, the distribution pattern and presence of estrogen and progesterone receptors in epithelial, stromal, endothelial and inflammatory cells in Epulis Fissuratum was investigated. Materials and Methods: This cross-sectional study was carried out on 30 samples of paraffin blocks with Epulis Fissuratum diagnosis and 30 samples of normal mucosal tissues as a control group who have had surgery as a margin beside the above lesions and had been obtained from the oral and maxillofacial pathology departement of Babol Dental School since 2003 up to 2010. Intensity of staining and immunoreactivity were evaluated using subjective index and considering the positive control group (breast carcinoma.Results: Epithelial, stromal, endothelial and inflammatory cells didn’t show reaction with monoclonal antibodies against estrogen and progesterone in none of the samples. Conclusion: It seems that the hypothesis of the existence of estrogen and progesterone receptors in epulis fissuratum and normal oral mucosa is ruled out. The possibility of direct effect of estrogen and progesterone in occurring of epulis fissuratum is rejected.

  19. Facile screening of potential xenoestrogens by an estrogen receptor-based reusable optical biosensor.

    Science.gov (United States)

    Liu, Lanhua; Zhou, Xiaohong; Lu, Yun; Shan, Didi; Xu, Bi; He, Miao; Shi, Hanchang; Qian, Yi

    2017-11-15

    The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of screening xenoestrogens. We reported an estrogen receptor (ER)-based reusable fiber biosensor for facile screening estrogenic compounds in environment. The bioassay is based on the competition of xenoestrogens with 17β-estradiol (E 2 ) for binding to the recombinant receptor of human estrogen receptor α (hERα) protein, leaving E 2 free to bind to fluorophore-labeled anti-E 2 monoclonal antibody. Unbound anti-E 2 antibody then binds to the immobilized E 2 -protein conjugate on the fiber surface, and is detected by fluorescence emission induced by evanescent field. As expected, the stronger estrogenic activity of xenoestrogen would result in the weaker fluorescent signal. Three estrogen-agonist compounds, diethylstilbestrol (DES), 4-n-nonylphenol (NP) and 4-n-octylphenol (OP), were chosen as a paradigm for validation of this assay. The rank order of estrogenic potency determined by this biosensor was DES>OP>NP, which were consistent with the published results in numerous studies. Moreover, the E 2 -protein conjugate modified optical fiber was robust enough for over 300 sensing cycles with the signal recoveries ranging from 90% to 100%. In conclusion, the biosensor is reusable, reliable, portable and amenable to on-line operation, providing a facile, efficient and economical alternative to screen potential xenoestrogens in environment. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Dietary acrylamide intake and estrogen and progesterone receptor-defined postmenopausal breast cancer risk

    DEFF Research Database (Denmark)

    Pedersen, Grete S; Hogervorst, Janneke G F; Schouten, Leo J

    2010-01-01

    and risk of postmenopausal breast cancer stratified by estrogen and progesterone receptor status. This study was embedded within the Netherlands Cohort Study on diet and cancer, which was initiated in 1986 enrolling 62,573 women aged 55-69 years at baseline. After 13.3 years of follow-up, 2225 incident...... breast cancer cases were ascertained, with hormone receptor status information for 43%. Cox proportional hazards analysis was applied to determine hazard ratios in quintiles of dietary acrylamide intake stratifying on estrogen receptor (ER) and progesterone receptor (PR) and smoking status....... No association was observed for overall breast cancer or receptor-negative breast cancer risk, irrespective of smoking status. A statistically non-significantly increased risk of ER positive, PR positive and joint receptor-positive breast cancer was found in never-smoking women. The multivariable-adjusted hazard...

  1. Structural Stereochemistry of Androstene Hormones Determines Interactions with Human Androgen, Estrogen, and Glucocorticoid Receptors

    Directory of Open Access Journals (Sweden)

    Thomas L. Shaak

    2013-01-01

    Full Text Available DHEA, 17α-AED, 17β-AED, and 17β-AET exhibit strong biological activity that has been attributed to androgenic, estrogenic, or antiglucocorticoid activity in vivo and in vitro. This study compared DHEA, 17α-AED, 17β-AED, and 17β-AET for their ability to activate the human AR, ER, and GR and determine the relative androgenicity, estrogenicity, and glucocorticoid activity. The results show that, at the receptor level, these androstene hormones are weak AR and even weaker ER activators. Direct androstene hormone activation of the human AR, ERα, and ERβ may not be essential for their biological function. Similarly, these hormones indirectly activated the human GR, only in the presence of high dexamethasone concentrations. These results underscore the major difference between androstene hormone interactions with these nuclear receptors and their biological effects.

  2. Estrogens induce rapid cytoskeleton re-organization in human dermal fibroblasts via the non-classical receptor GPR30.

    Directory of Open Access Journals (Sweden)

    Julie Carnesecchi

    Full Text Available The post-menopausal decrease in estrogen circulating levels results in rapid skin deterioration pointing out to a protective effect exerted by these hormones. The identity of the skin cell type responding to estrogens is unclear as are the cellular and molecular processes they elicit. Here, we reported that lack of estrogens induces rapid re-organization of the human dermal fibroblast cytoskeleton resulting in striking cell shape change. This morphological change was accompanied by a spatial re-organization of focal adhesion and a substantial reduction of their number as evidenced by vinculin and actin co-staining. Cell morphology and cytoskeleton organization was fully restored upon 17β-estradiol (E2 addition. Treatment with specific ER antagonists and cycloheximide respectively showed that the E2 acts independently of the classical Estrogen Receptors and that cell shape change is mediated by non-genomic mechanisms. E2 treatment resulted in a rapid and transient activation of ERK1/2 but not Src or PI3K. We show that human fibroblasts express the non-classical E2 receptor GPR30 and that its agonist G-1 phenocopies the effect of E2. Inhibiting GPR30 through treatment with the G-15 antagonist or specific shRNA impaired E2 effects. Altogether, our data reveal a novel mechanism by which estrogens act on skin fibroblast by regulating cell shape through the non-classical G protein-coupled receptor GPR30 and ERK1/2 activation.

  3. Estrogens induce rapid cytoskeleton re-organization in human dermal fibroblasts via the non-classical receptor GPR30.

    Science.gov (United States)

    Carnesecchi, Julie; Malbouyres, Marilyne; de Mets, Richard; Balland, Martial; Beauchef, Gallic; Vié, Katell; Chamot, Christophe; Lionnet, Claire; Ruggiero, Florence; Vanacker, Jean-Marc

    2015-01-01

    The post-menopausal decrease in estrogen circulating levels results in rapid skin deterioration pointing out to a protective effect exerted by these hormones. The identity of the skin cell type responding to estrogens is unclear as are the cellular and molecular processes they elicit. Here, we reported that lack of estrogens induces rapid re-organization of the human dermal fibroblast cytoskeleton resulting in striking cell shape change. This morphological change was accompanied by a spatial re-organization of focal adhesion and a substantial reduction of their number as evidenced by vinculin and actin co-staining. Cell morphology and cytoskeleton organization was fully restored upon 17β-estradiol (E2) addition. Treatment with specific ER antagonists and cycloheximide respectively showed that the E2 acts independently of the classical Estrogen Receptors and that cell shape change is mediated by non-genomic mechanisms. E2 treatment resulted in a rapid and transient activation of ERK1/2 but not Src or PI3K. We show that human fibroblasts express the non-classical E2 receptor GPR30 and that its agonist G-1 phenocopies the effect of E2. Inhibiting GPR30 through treatment with the G-15 antagonist or specific shRNA impaired E2 effects. Altogether, our data reveal a novel mechanism by which estrogens act on skin fibroblast by regulating cell shape through the non-classical G protein-coupled receptor GPR30 and ERK1/2 activation.

  4. Long-term estrogen therapy and 5-HT(2A) receptor binding in postmenopausal women; a single photon emission tomography (SPET) study

    NARCIS (Netherlands)

    Compton, J.; Travis, M. J.; Norbury, R.; Erlandsson, K.; van Amelsvoort, T.; Daly, E.; Waddington, W.; Matthiasson, P.; Eersels, J. L. H.; Whitehead, M.; Kerwin, R. W.; Ell, P. J.; Murphy, D. G. M.

    2008-01-01

    Variation in estrogen level is reported by some to affect brain maturation and memory. The neurobiological basis for this may include modulation of the serotonergic system. No neuroimaging studies have directly examined the effect of extended estrogen therapy (ET), on the 5-HT(2A) receptor in human

  5. Small leucine zipper protein functions as a negative regulator of estrogen receptor α in breast cancer.

    Directory of Open Access Journals (Sweden)

    Juyeon Jeong

    Full Text Available The nuclear transcription factor estrogen receptor α (ERα plays a critical role in breast cancer progression. ERα acts as an important growth stimulatory protein in breast cancer and the expression level of ERα is tightly related to the prognosis and treatment of patients. Small leucine zipper protein (sLZIP functions as a transcriptional cofactor by binding to various nuclear receptors, including glucocorticoid receptor, androgen receptor, and peroxisome proliferator-activated receptor γ. However, the role of sLZIP in the regulation of ERα and its involvement in breast cancer progression is unknown. We found that sLZIP binds to ERα and represses the transcriptional activity of ERα in ERα-positive breast cancer cells. sLZIP also suppressed the expression of ERα target genes. sLZIP disrupted the binding of ERα to the estrogen response element of the target gene promoter, resulting in suppression of cell proliferation. sLZIP is a novel co-repressor of ERα, and plays a negative role in ERα-mediated cell proliferation in breast cancer.

  6. The estrogen-related receptors and the adipocyte.

    Science.gov (United States)

    Carnesecchi, Julie; Vanacker, Jean-Marc

    2013-08-01

    The estrogen-related receptors (ERRα, β, and γ) are orphan members of the nuclear receptor superfamily. ERRα and γ are highly expressed in tissues displaying elevated energy demands and are involved in several aspects of energetic metabolism, which they regulate mostly in association with members of the PGC-1 coactivator family. These activities have mostly been documented in the liver, heart, or skeletal muscle. ERRα and γ are also highly expressed in adipocytes. Their precise roles in this cell type are less documented, although published data indicate that they contribute to cell differentiation as well as functionality. This review describes these activities.

  7. Oxytocin and Estrogen Receptor β in the Brain: An Overview

    Directory of Open Access Journals (Sweden)

    Alexandra eAcevedo-Rodriguez

    2015-10-01

    Full Text Available Oxytocin is a neuropeptide synthesized primarily by neurons of the paraventricular and supraoptic nuclei of the hypothalamus. These neurons have axons that project into the posterior pituitary and release oxytocin into the bloodstream to promote labor and lactation; however, oxytocin neurons also project to other brain areas where it plays a role in numerous brain functions. Oxytocin binds to the widely expressed oxytocin receptor, and, in doing so, it regulates homeostatic processes, social recognition and fear conditioning. In addition to these functions, oxytocin decreases neuroendocrine stress signaling and anxiety-related and depression-like behaviors. Steroid hormones differentially modulate stress responses and alter oxytocin receptor expression. In particular, estrogen receptor β activation has been found to both reduce anxiety-related behaviors and increase oxytocin peptide transcription, suggesting a role for oxytocin in this estrogen receptor β mediated anxiolytic effect. Further research is needed to identify modulators of oxytocin signaling and the pathways utilized and to elucidate molecular mechanisms controlling oxytocin expression to allow better therapeutic manipulations of this system in patient populations.

  8. Targeted basic research to highlight the role of estrogen and estrogen receptors in the cardiovascular system.

    Science.gov (United States)

    Dworatzek, Elke; Mahmoodzadeh, Shokoufeh

    2017-05-01

    Epidemiological, clinical and animal studies revealed that sex differences exist in the manifestation and outcome of cardiovascular disease (CVD). The underlying molecular mechanisms implicated in these sex differences are not fully understood. The reasons for sex differences in CVD are definitely multifactorial, but major evidence points to the contribution of sex steroid hormone, 17β-estradiol (E2), and its receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). In this review, we summarize past and present studies that implicate E2 and ER as important determinants of sexual dimorphism in the physiology and pathophysiology of the heart. In particular, we give an overview of studies aimed to reveal the role of E2 and ER in the physiology of the observed sex differences in CVD using ER knock-out mice. Finally, we discuss recent findings from novel transgenic mouse models, which have provided new information on the sexual dimorphic roles of ER specifically in cardiomyocytes under pathological conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The Distinct Effects of Estrogen and Hydrostatic Pressure on Mesenchymal Stem Cells Differentiation: Involvement of Estrogen Receptor Signaling.

    Science.gov (United States)

    Zhao, Ying; Yi, Fei-Zhou; Zhao, Yin-Hua; Chen, Yong-Jin; Ma, Heng; Zhang, Min

    2016-10-01

    This study aimed to investigate the differential and synergistic effects of mechanical stimulation and estrogen on the proliferation and osteogenic or chondrogenic differentiation potential of bone marrow mesenchymal stem cells (BMSCs) and the roles of estrogen receptor (ER) in them. BMSCs were isolated and cultured using the whole bone marrow adherence method, and flow cytometry was used to identify the surface marker molecules of BMSCs. Cells were pre-treated with 1 nM 17β-estradiol or 1 nM of the estrogen receptor antagonist tamoxifen. Then, the cells were stimulated with hydrostatic pressure. Assessment included flow cytometry analysis of the cell cycle; immunofluorescent staining for F-actin; protein quantification for MAPK protein; and mRNA analysis for Col I, OCN, OPN and BSP after osteogenic induction and Sox-9, Aggrecan and Col-II after chondrogenic induction. Hydrostatic pressure (90 kPa/1 h) and 1 nM 17β-estradiol enhanced the cellular proliferation ability and the cytoskeleton activity but without synergistic biological effects. Estrogen activated ERKs and JNKs simultaneously and promoted the osteogenic differentiation, whereas the pressure just caused JNK-1/2 activation and promoted the chondrogenic differentiation of BMSCs. Estrogen had antagonism effect on chondrogenic promotion of hydrostatic pressure. Mechanobiological effects of hydrostatic pressure are closely associated with ERα activity. MAPK molecules and F-actin were likely to be important mediator molecules in the ER-mediated mechanotransduction of BMSCs.

  10. Estrogen receptor alpha localization in the testes of men with normal spermatogenesis Estrogen receptor alpha localization in the testes of men with normal spermatogenesis

    OpenAIRE

    Eliza Filipiak; Dagmara Suliborska; Maria Laszczynska; Renata Walczak-Jedrzejowska; Elzbieta Oszukowska; Katarzyna Marchlewska; Krzysztof Kula; Jolanta Slowikowska-Hilczer

    2012-01-01

    It is known that estrogens act on the male reproductive tract by binding to estrogen receptors (ER) a and
    b. However, studies on ER localization in the human testis are discordant. The aim of this study was to investigate
    the localization of ERa in the testes of adult men with normal spermatogenesis. Semen analysis of ten adult men
    revealed azoospermia. FSH, LH and testosterone serum concentrations were within normal values, and the volume
    of the te...

  11. Increased Level of Phosphorylated ShcA Measured by Chemiluminescence-Linked Immunoassay Is a Predictor of Good Prognosis in Primary Breast Cancer Expressing Low Levels of Estrogen Receptor

    International Nuclear Information System (INIS)

    Cicenas, Jonas; Küng, Willy; Eppenberger, Urs; Eppenberger-Castori, Serenella

    2010-01-01

    The SH2 domain-containing adaptor protein ShcA is a proto-oncogene involved in growth factor receptor signaling. The role of phosphorylated ShcA is to link receptor tyrosine kinases with the SH2-containing adaptor protein Grb2, thus facilitating signal transduction from receptor tyrosine kinases to Ras, leading to MAPK activation. The present study was designed to investigate the prognostic significance of phosphorylated ShcA in primary breast cancer and its association in the interactions between the ER and ErbB2 pathways. Using a two-site chemiluminescence-linked immunosorbent assay, we detected the quantitative expression levels of total tyrosine- and threonine-phosphorylated ShcA in cytosol fractions obtained from fresh frozen tissue samples of 153 selected primary breast cancer patients. ShcA phosphorylation was not associated with nodal status, estrogen receptor (ER) status or grading. High levels of both tyrosine (pYShcA) and serine (pSShcA) phosphorylated ShcA correlated with good prognosis (p < 0.01), with respect to both disease-free (DFS) and overall survival (OS). In addition, pShcA levels were found to correlate with threonine-phosphorylated ErbB2 and inversely with phosphorylated Akt (pAkt), as well as ErbB2 and ER expression levels. Our findings demonstrate that ShcA activation in primary breast cancer patients correlates with low levels of ER, and is associated with good prognosis

  12. Vascular measurements correlate with estrogen receptor status

    International Nuclear Information System (INIS)

    Lloyd, Mark C; Alfarouk, Khalid O; Verduzco, Daniel; Bui, Marilyn M; Gillies, Robert J; Ibrahim, Muntaser E; Brown, Joel S; Gatenby, Robert A

    2014-01-01

    Breast carcinoma can be classified as either Estrogen Receptor (ER) positive or negative by immunohistochemical phenotyping, although ER expression may vary from 1 to 100% of malignant cells within an ER + tumor. This is similar to genetic variability observed in other tumor types and is generally viewed as a consequence of intratumoral evolution driven by random genetic mutations. Here we view cellular evolution within tumors as a classical Darwinian system in which variations in molecular properties represent predictable adaptations to spatially heterogeneous environmental selection forces. We hypothesize that ER expression is a successful adaptive strategy only if estrogen is present in the microenvironment. Since the dominant source of estrogen is blood flow, we hypothesized that, in general, intratumoral regions with higher blood flow would contain larger numbers of ER + cells when compared to areas of low blood flow and in turn necrosis. This study used digital pathology whole slide image acquisition and advanced image analysis algorithms. We examined the spatial distribution of ER + and ER- cells, vascular density, vessel area, and tissue necrosis within histological sections of 24 breast cancer specimens. These data were correlated with the patients ER status and molecular pathology report findings. ANOVA analyses revealed a strong correlation between vascular area and ER expression and between high fractional necrosis and absent ER expression (R 2 = 39%; p < 0.003 and R 2 = 46%; p < 0.001), respectively). ER expression did not correlate with tumor grade or size. We conclude that ER expression can be understood as a Darwinian process and linked to variations in estrogen delivery by temporal and spatial heterogeneity in blood flow. This correlation suggests strategies to promote intratumoral blood flow or a cyclic introduction of estrogen in the treatment schedule could be explored as a counter-intuitive approach to increase the efficacy of anti-estrogen

  13. Serum estrogen and SHBG levels and breast cancer incidence among users and never users of hormone replacement therapy

    DEFF Research Database (Denmark)

    Würtz, Anne Mette Lund; Tjønneland, Anne; Christensen, Jane

    2012-01-01

    OBJECTIVE: Levels of endogenous estrogen and SHBG are associated with risk of breast cancer among women who have never used hormone replacement therapy (HRT). We investigated these associations in both never and baseline users of HRT. METHODS: A nested case-control study was conducted within the ...... and baseline HRT users. More studies are needed to support the findings for HRT users and to further investigate estrogen levels in relation to estrogen receptor-specific breast cancer and other histological and molecular subtypes.......OBJECTIVE: Levels of endogenous estrogen and SHBG are associated with risk of breast cancer among women who have never used hormone replacement therapy (HRT). We investigated these associations in both never and baseline users of HRT. METHODS: A nested case-control study was conducted within...... logistic regression yielded incidence rate ratios and 95 % confidence intervals for exposures analyzed continuously and categorically in models adjusted for potential confounders. RESULTS: Modest direct associations were identified between estrogen levels and breast cancer incidence among both never...

  14. Role of Estrogen Receptor Signaling in Breast Cancer Metastasis

    International Nuclear Information System (INIS)

    Roy, S.S.; Vadlamudi, R.K.

    2012-01-01

    Metastatic breast cancer is a life-threatening stage of cancer and is the leading cause of death in advanced breast cancer patients. Estrogen signaling and the estrogen receptor (ER) are implicated in breast cancer progression, and the majority of the human breast cancers start out as estrogen dependent. Accumulating evidence suggests that ER signaling is complex, involving coregulatory proteins and extranuclear actions. ER-coregualtory proteins are tightly regulated under normal conditions with miss expression primarily reported in cancer. Deregulation of ER coregualtors or ER extranuclear signaling has potential to promote metastasis in ER-positive breast cancer cells. This review summarizes the emerging role of ER signaling in promoting metastasis of breast cancer cells, discusses the molecular mechanisms by which ER signaling contributes to metastasis, and explores possible therapeutic targets to block ER-driven metastasis

  15. Social memory associated with estrogen receptor polymorphisms in women

    Science.gov (United States)

    Karlsson, Sara; Henningsson, Susanne; Hovey, Daniel; Zettergren, Anna; Jonsson, Lina; Cortes, Diana S.; Melke, Jonas; Laukka, Petri; Fischer, Håkan

    2016-01-01

    The ability to recognize the identity of faces and voices is essential for social relationships. Although the heritability of social memory is high, knowledge about the contributing genes is sparse. Since sex differences and rodent studies support an influence of estrogens and androgens on social memory, polymorphisms in the estrogen and androgen receptor genes (ESR1, ESR2, AR) are candidates for this trait. Recognition of faces and vocal sounds, separately and combined, was investigated in 490 subjects, genotyped for 10 single nucleotide polymorphisms (SNPs) in ESR1, four in ESR2 and one in the AR. Four of the associations survived correction for multiple testing: women carrying rare alleles of the three ESR2 SNPs, rs928554, rs1271572 and rs1256030, in linkage disequilibrium with each other, displayed superior face recognition compared with non-carriers. Furthermore, the uncommon genotype of the ESR1 SNP rs2504063 was associated with better recognition of identity through vocal sounds, also specifically in women. This study demonstrates evidence for associations in women between face recognition and variation in ESR2, and recognition of identity through vocal sounds and variation in ESR1. These results suggest that estrogen receptors may regulate social memory function in humans, in line with what has previously been established in mice. PMID:26955855

  16. The Role of Estrogen Receptor β in Prostate Cancer

    OpenAIRE

    Christoforou, Paraskevi; Christopoulos, Panagiotis F; Koutsilieris, Michael

    2014-01-01

    Although androgen receptor (AR) signaling is the main molecular tool regulating growth and function of the prostate gland, estrogen receptor β (ERβ) is involved in the differentiation of prostatic epithelial cells and numerous antiproliferative actions on prostate cancer cells. However, ERβ splice variants have been associated with prostate cancer initiation and progression mechanisms. ERβ is promising as an anticancer therapy and in the prevention of prostate cancer. Herein, we review the re...

  17. The Role of Skp1-Cul1-F-box Ubiquitin Ligases in Src-Stimulated Estrogen Receptor Proteolysis and Estrogen Receptor Target Gene Expression

    Science.gov (United States)

    2014-03-01

    Korach,K.S. (2006). Estrogen receptors and human disease. J Clin Invest 116, 561‐ 570 .  Glickman,M.H.  and  Ciechanover,A.  (2002).  The  ubiquitin...P, Nola E et al. Tyrosine kinas/p21ras/MAP-kinase pathway activation by estradiol receptor complex in MCF-7 cells. EMBO J 1996; 15: 1292–1300. 2...elements (EREs) on target gene promoters in order to activate or repress transcription. • Multiple signalling pathways downstream of receptor tyrosine

  18. Estrogen provides neuroprotection against brain edema and blood brain barrier disruption through both estrogen receptors α and β following traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Vida Naderi

    2015-02-01

    Full Text Available Objective(s:Estrogen (E2 has neuroprotective effects on blood-brain-barrier (BBB after traumatic brain injury (TBI. In order to investigate the roles of estrogen receptors (ERs in these effects, ER-α antagonist (MPP and, ER-β antagonist (PHTPP, or non-selective estrogen receptors antagonist (ICI 182780 were administered. Materials and Methods: Ovariectomized rats were divided into 10 groups, as follows: Sham, TBI, E2, oil, MPP+E2, PHTPP+E2, MPP+PHTPP+E2, ICI+E2, MPP, and DMSO. E2 (33.3 µg/Kg or oil were administered 30 min after TBI. 1 dose (150 µg/Kg of each of MPP, PHTPP, and (4 mg/kg ICI182780 was injected two times, 24 hr apart, before TBI and estrogen treatment. BBB disruption (Evans blue content and brain edema (brain water content evaluated 5 hr and 24 hr after the TBI were evaluated, respectively. Results: The results showed that E2 reduced brain edema after TBI compared to vehicle (P

  19. Long-term Safety of Pregnancy Following Breast Cancer According to Estrogen Receptor Status

    DEFF Research Database (Denmark)

    Lambertini, Matteo; Kroman, Niels; Ameye, Lieveke

    2018-01-01

    Safety of pregnancy in women with history of estrogen receptor (ER)-positive breast cancer remains controversial. In this multicenter case-control study, 333 patients with pregnancy after breast cancer were matched (1:3) to 874 nonpregnant patients of similar characteristics, adjusting for guaran......Safety of pregnancy in women with history of estrogen receptor (ER)-positive breast cancer remains controversial. In this multicenter case-control study, 333 patients with pregnancy after breast cancer were matched (1:3) to 874 nonpregnant patients of similar characteristics, adjusting...

  20. An energetic orphan in an endocrine tissue: a revised perspective of the function of estrogen receptor-related receptor alpha in bone and cartilage.

    Science.gov (United States)

    Bonnelye, Edith; Aubin, Jane E

    2013-02-01

    Estrogen receptor-related receptor alpha (ERRα) is an orphan nuclear receptor with sequence homology to the estrogen receptors, ERα/β, but it does not bind estrogen. ERRα not only plays a functional role in osteoblasts but also in osteoclasts and chondrocytes. In addition, the ERRs, including ERRα, can be activated by coactivators such as peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC1α and β) and are implicated in adipogenesis, fatty acid oxidation, and oxidative stress defense, suggesting that ERRα-through its activity in bone resorption and adipogenesis--may regulate the insulin and leptin pathways and contribute to aging-related changes in bone and cartilage. In this review, we discuss data on ERRα and its cellular and molecular modes of action, which have broad implications for considering the potential role of this orphan receptor in cartilage and bone endocrine function, on whole-organism physiology, and in the bone aging process. Copyright © 2013 American Society for Bone and Mineral Research.

  1. Discovery of estrogen receptor α modulators from natural compounds in Si-Wu-Tang series decoctions using estrogen-responsive MCF-7 breast cancer cells.

    Science.gov (United States)

    Liu, Li; Ma, Hongyue; Tang, Yuping; Chen, Wenxing; Lu, Yin; Guo, Jianming; Duan, Jin-Ao

    2012-01-01

    The binding between the estrogen receptor α (ER-α) and a variety of compounds in traditional Chinese formulae, Si-Wu-Tang (SWT) series decoctions, was studied using a stably-transfected human breast cancer cell line (MVLN). In 38 compounds tested from SWT series decoctions, the estrogen-like activity of 22 compounds was above 60% in 20 μg mL(-1). Furthermore, theoretical affinity of these compounds was certificated using the functional virtual screen of ER-α modulators by FlexX-Pharm. The accuracy of functional virtual screening of ER-α modulators could reach to 77.27%. The results showed that some compounds, such as organic acids and flavones in SWT series decoctions could be used as selective estrogen receptor modulators (SERMs) and could be selected for further development as potential agents for estrogen related diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Brain aromatase (Cyp19A2) and estrogen receptors, in larvae and adult pejerrey fish Odontesthes bonariensis: Neuroanatomical and functional relations

    Science.gov (United States)

    Strobl-Mazzulla, P. H.; Lethimonier, C.; Gueguen, M.M.; Karube, M.; Fernandino, J.I.; Yoshizaki, G.; Patino, R.; Strussmann, C.A.; Kah, O.; Somoza, G.M.

    2008-01-01

    Although estrogens exert many functions on vertebrate brains, there is little information on the relationship between brain aromatase and estrogen receptors. Here, we report the cloning and characterization of two estrogen receptors, ?? and ??, in pejerrey. Both receptors' mRNAs largely overlap and were predominantly expressed in the brain, pituitary, liver, and gonads. Also brain aromatase and estrogen receptors were up-regulated in the brain of estradiol-treated males. In situ hybridization was performed to study in more detail, the distribution of the two receptors in comparison with brain aromatase mRNA in the brain of adult pejerrey. The estrogen receptors' mRNAs exhibited distinct but partially overlapping patterns of expression in the preoptic area and the mediobasal hypothalamus, as well as in the pituitary gland. Moreover, the estrogen receptor ??, but not ??, were found to be expressed in cells lining the preoptic recess, similarly as observed for brain aromatase. Finally, it was shown that the onset expression of brain aromatase and both estrogen receptors in the head of larvae preceded the morphological differentiation of the gonads. Because pejerrey sex differentiation is strongly influenced by temperature, brain aromatase expression was measured during the temperature-sensitive window and was found to be significantly higher at male-promoting temperature. Taken together these results suggest close neuroanatomical and functional relationships between brain aromatase and estrogen receptors, probably involved in the sexual differentiation of the brain and raising interesting questions on the origin (central or peripheral) of the brain aromatase substrate. ?? 2008 Elsevier Inc.

  3. Expression of Estrogen Alpha and Beta Receptors in Prostate ...

    African Journals Online (AJOL)

    Expression of Estrogen Alpha and Beta Receptors in Prostate Cancer and Hyperplasia: Immunohistochemical Analysis. ... Additionally, ER-α was not expressed in either luminal or basal cells in any of the 35 BPH cases. However ... Key Words: ER-α, ER-β, prostate, hyperplasia, premalignant, cancer, immunohistochemistry ...

  4. The Cell Surface Estrogen Receptor, G Protein- Coupled Receptor 30 (GPR30, is Markedly Down Regulated During Breast Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Indira Poola

    2008-01-01

    Full Text Available Background: GPR30 is a cell surface estrogen receptor that has been shown to mediate a number of non-genomic rapid effects of estrogen and appear to balance the signaling of estrogen and growth factors. In addition, progestins appear to use GPR30 for their actions. Therefore, GPR30 could play a critical role in hormonal regulation of breast epithelial cell integrity. Deregulation of the events mediated by GPR30 could contribute to tumorigenesis.Methods: To understand the role of GPR30 in the deregulation of estrogen signaling processes during breast carcinogenesis, we have undertaken this study to investigate its expression at mRNA levels in tumor tissues and their matched normal tissues. We compared its expression at mRNA levels by RT quantitative real-time PCR relative to GAPDH in ERα”—positive (n = 54 and ERα”—negative (n = 45 breast cancer tissues to their matched normal tissues.Results: We report here, for the first time, that GPR30 mRNA levels were significantly down-regulated in cancer tissues in comparison with their matched normal tissues (p 0.0001 by two sided paired t-test. The GPR30 expression levels were significantly lower in tumor tissues from patients (n = 29 who had lymph node metastasis in comparison with tumors from patients (n = 53 who were negative for lymph node metastasis (two sample t-test, p 0.02, but no association was found with ERα, PR and other tumor characteristics.Conclusions: Down-regulation of GPR30 could contribute to breast tumorigenesis and lymph node metastasis.

  5. Increased Level of Phosphorylated ShcA Measured by Chemiluminescence-Linked Immunoassay Is a Predictor of Good Prognosis in Primary Breast Cancer Expressing Low Levels of Estrogen Receptor

    Directory of Open Access Journals (Sweden)

    Serenella Eppenberger-Castori

    2010-03-01

    Full Text Available The SH2 domain-containing adaptor protein ShcA is a proto-oncogene involved in growth factor receptor signaling. The role of phosphorylated ShcA is to link receptor tyrosine kinases with the SH2-containing adaptor protein Grb2, thus facilitating signal transduction from receptor tyrosine kinases to Ras, leading to MAPK activation. The present study was designed to investigate the prognostic significance of phosphorylated ShcA in primary breast cancer and its association in the interactions between the ER and ErbB2 pathways. Using a two-site chemiluminescence-linked immunosorbent assay, we detected the quantitative expression levels of total tyrosine- and threonine-phosphorylated ShcA in cytosol fractions obtained from fresh frozen tissue samples of 153 selected primary breast cancer patients. ShcA phosphorylation was not associated with nodal status, estrogen receptor (ER status or grading. High levels of both tyrosine (pYShcA and serine (pSShcA phosphorylated ShcA correlated with good prognosis (p < 0.01, with respect to both disease-free (DFS and overall survival (OS. In addition, pShcA levels were found to correlate with threonine-phosphorylated ErbB2 and inversely with phosphorylated Akt (pAkt, as well as ErbB2 and ER expression levels. Our findings demonstrate that ShcA activation in primary breast cancer patients correlates with low levels of ER, and is associated with good prognosis.

  6. Integration of Nuclear- and Extranuclear-Initiated Estrogen Receptor Signaling in Breast Cancer Cells

    Science.gov (United States)

    Madak Erdogan, Zeynep

    2009-01-01

    Estrogenic hormones exert their effects through binding to Estrogen Receptors (ERs), which work in concert with coregulators and extranuclear signaling pathways to control gene expression in normal as well as cancerous states, including breast tumors. In this thesis, we have used multiple genome-wide analysis tools to elucidate various ways that…

  7. In situ aromatase expression in primary tumor is associated with estrogen receptor expression but is not predictive of response to endocrine therapy in advanced breast cancer

    DEFF Research Database (Denmark)

    Lykkesfeldt, Anne E; Henriksen, Katrine L; Rasmussen, Birgitte B

    2009-01-01

    BACKGROUND: New, third-generation aromatase inhibitors (AIs) have proven comparable or superior to the anti-estrogen tamoxifen for treatment of estrogen receptor (ER) and/or progesterone receptor (PR) positive breast cancer. AIs suppress total body and intratumoral estrogen levels. It is unclear...... whether in situ carcinoma cell aromatization is the primary source of estrogen production for tumor growth and whether the aromatase expression is predictive of response to endocrine therapy. Due to methodological difficulties in the determination of the aromatase protein, COX-2, an enzyme involved...... of advanced breast cancer. Semi-quantitative immunohistochemical (IHC) analysis was performed for ER, PR, COX-2 and aromatase using Tissue Microarrays (TMAs). Aromatase was also analyzed using whole sections (WS). Kappa analysis was applied to compare association of protein expression levels. Univariate...

  8. Glyphosate induces human breast cancer cells growth via estrogen receptors.

    Science.gov (United States)

    Thongprakaisang, Siriporn; Thiantanawat, Apinya; Rangkadilok, Nuchanart; Suriyo, Tawit; Satayavivad, Jutamaad

    2013-09-01

    Glyphosate is an active ingredient of the most widely used herbicide and it is believed to be less toxic than other pesticides. However, several recent studies showed its potential adverse health effects to humans as it may be an endocrine disruptor. This study focuses on the effects of pure glyphosate on estrogen receptors (ERs) mediated transcriptional activity and their expressions. Glyphosate exerted proliferative effects only in human hormone-dependent breast cancer, T47D cells, but not in hormone-independent breast cancer, MDA-MB231 cells, at 10⁻¹² to 10⁻⁶M in estrogen withdrawal condition. The proliferative concentrations of glyphosate that induced the activation of estrogen response element (ERE) transcription activity were 5-13 fold of control in T47D-KBluc cells and this activation was inhibited by an estrogen antagonist, ICI 182780, indicating that the estrogenic activity of glyphosate was mediated via ERs. Furthermore, glyphosate also altered both ERα and β expression. These results indicated that low and environmentally relevant concentrations of glyphosate possessed estrogenic activity. Glyphosate-based herbicides are widely used for soybean cultivation, and our results also found that there was an additive estrogenic effect between glyphosate and genistein, a phytoestrogen in soybeans. However, these additive effects of glyphosate contamination in soybeans need further animal study. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

    International Nuclear Information System (INIS)

    Shao, Ruyue; Fang, Liaoqiong; Xing, Ruoxi; Xiong, Yu; Fang, Liaoqiong; Wang, Zhibiao

    2015-01-01

    Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERα and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E_2) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E_2 concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights: • In both multiple

  10. Oxytocin and Estrogen Receptor β in the Brain: An Overview.

    Science.gov (United States)

    Acevedo-Rodriguez, Alexandra; Mani, Shaila K; Handa, Robert J

    2015-01-01

    Oxytocin (OT) is a neuropeptide synthesized primarily by neurons of the paraventricular and supraoptic nuclei of the hypothalamus. These neurons have axons that project into the posterior pituitary and release OT into the bloodstream to promote labor and lactation; however, OT neurons also project to other brain areas where it plays a role in numerous brain functions. OT binds to the widely expressed OT receptor (OTR), and, in doing so, it regulates homeostatic processes, social recognition, and fear conditioning. In addition to these functions, OT decreases neuroendocrine stress signaling and anxiety-related and depression-like behaviors. Steroid hormones differentially modulate stress responses and alter OTR expression. In particular, estrogen receptor β activation has been found to both reduce anxiety-related behaviors and increase OT peptide transcription, suggesting a role for OT in this estrogen receptor β-mediated anxiolytic effect. Further research is needed to identify modulators of OT signaling and the pathways utilized and to elucidate molecular mechanisms controlling OT expression to allow better therapeutic manipulations of this system in patient populations.

  11. The distribution of estrogen receptor in various organs of rabbit

    International Nuclear Information System (INIS)

    Son, H.Y.; In, J.W.; Min, B.S.

    1978-01-01

    For clinical application of radioreceptor assay, we studied preliminarily the distribution of estrogen receptor in various organs of rabbit by a dextran-charcoal method using 6,7- 3 H-es-tradiol. The results were expressed as binding index, which is the ratio of specific estradiol receptor binding radioactivity to total radioactivity. The materials consist of 5 female rabbits and 3 male rabbits. For female rabbits the binding index was highest in the uterine tissue. This binding index of the uterine tissue was 9.4 times that of the liver, 21.9 times that of the kidney, 24.6 times that of the brain, 28.1 times that of the lung and 65.7 times that of the muscle. For male rabbits the binding index was highest in the liver and decreased in the order of the kidney, the testis, the lung, the brain and the muscle. It is suggested that the estrogen receptor is not confined to any specific target organ but is widely distributed in the various organs, to a different degree. (author)

  12. The Distribution of Estrogen Receptor in Various Organs of Rabbit

    International Nuclear Information System (INIS)

    Son, Ho Young; In, Jae Whan; Min, Byong Sok

    1978-01-01

    For clinical application of radioreceptor assay, we studied preliminarily the distribution of estrogen receptor in various organs of rabbit by a dextran-charcoal method using 6, 7- 3 H-estradiol. The results were expressed as binding index, which is the ratio of specific estradiol receptor binding radioactivity to total radioactivity. The materials consist of 5 female rabbits and 3 male rabbits. The results were as follows: 1) Female rabbits. The binding index was highest in the uterine tissue. This binding index of the uterine tissue was 9.4 times that of the liver, 21.9 times that of the kidney, 24.6 times that of the brain, 28.1 times that of the lung and 65.7 times that of the muscle. 2) Male rabbits. The binding index was highest in the liver and decreased in the order of the kidney, the testis, the lung, the brain and the muscle. It is suggested that the estrogen receptor is not confined to any specific target organ but is widely distributed in the various organs, to a different degree.

  13. Estradiol coupling to human monocyte nitric oxide release is dependent on intracellular calcium transients: evidence for an estrogen surface receptor.

    Science.gov (United States)

    Stefano, G B; Prevot, V; Beauvillain, J C; Fimiani, C; Welters, I; Cadet, P; Breton, C; Pestel, J; Salzet, M; Bilfinger, T V

    1999-10-01

    We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase (cNOS) activity in human peripheral monocytes by acting on an estrogen surface receptor. NO release was measured in real time with an amperometric probe. 17beta-estradiol exposure to monocytes stimulated NO release within seconds in a concentration-dependent manner, whereas 17alpha-estradiol had no effect. 17beta-estradiol conjugated to BSA (E2-BSA) also stimulated NO release, suggesting mediation by a membrane surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized the action of both 17beta-estradiol and E2-BSA, whereas ICI 182,780, a selective inhibitor of the nuclear estrogen receptor, had no effect. We further showed, using a dual emission microfluorometry in a calcium-free medium, that the 17beta-estradiol-stimulated release of monocyte NO was dependent on the initial stimulation of intracellular calcium transients in a tamoxifen-sensitive process. Leeching out the intracellular calcium stores abolished the effect of 17beta-estradiol on NO release. RT-PCR analysis of RNA obtained from the cells revealed a strong estrogen receptor-alpha amplification signal and a weak beta signal. Taken together, a physiological dose of estrogen acutely stimulates NO release from human monocytes via the activation of an estrogen surface receptor that is coupled to increases in intracellular calcium.

  14. Distinct roles for aryl hydrocarbon receptor nuclear translocator and ah receptor in estrogen-mediated signaling in human cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Mark P Labrecque

    Full Text Available The activated AHR/ARNT complex (AHRC regulates the expression of target genes upon exposure to environmental contaminants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD. Importantly, evidence has shown that TCDD represses estrogen receptor (ER target gene activation through the AHRC. Our data indicates that AHR and ARNT act independently from each other at non-dioxin response element sites. Therefore, we sought to determine the specific functions of AHR and ARNT in estrogen-dependent signaling in human MCF7 breast cancer and human ECC-1 endometrial carcinoma cells. Knockdown of AHR with siRNA abrogates dioxin-inducible repression of estrogen-dependent gene transcription. Intriguingly, knockdown of ARNT does not effect TCDD-mediated repression of estrogen-regulated transcription, suggesting that AHR represses ER function independently of ARNT. This theory is supported by the ability of the selective AHR modulator 3',4'-dimethoxy-α-naphthoflavone (DiMNF to repress estrogen-inducible transcription. Furthermore, basal and estrogen-activated transcription of the genes encoding cathepsin-D and pS2 are down-regulated in MCF7 cells but up-regulated in ECC-1 cells in response to loss of ARNT. These responses are mirrored at the protein level with cathepsin-D. Furthermore, knock-down of ARNT led to opposite but corresponding changes in estrogen-stimulated proliferation in both MCF7 and ECC-1 cells. We have obtained experimental evidence demonstrating a dioxin-dependent repressor function for AHR and a dioxin-independent co-activator/co-repressor function for ARNT in estrogen signalling. These results provide us with further insight into the mechanisms of transcription factor crosstalk and putative therapeutic targets in estrogen-positive cancers.

  15. Variations in estrogen receptor ? gene and risk of dementia, and brain volumes on MRI.

    NARCIS (Netherlands)

    S.C.E. Schuit (Stephanie); A. Hofman (Albert); P.J. Koudstaal (Peter Jan); C.M. van Duijn (Cornelia); A.G. Uitterlinden (André); H.A.P. Pols (Huib); M.M.B. Breteler (Monique); J.B.J. van Meurs (Joyce); T. den Heijer (Tom)

    2004-01-01

    textabstractThe role of estrogens in Alzheimer's disease (AD) is controversial. We investigated the association between well-recognized, and potentially functional, polymorphisms in the estrogen receptor (ER) gene and the risk of AD in a prospective study of 6056 Caucasian older men and women aged

  16. Three nuclear and two membrane estrogen receptors in basal teleosts, Anguilla sp.: Identification, evolutionary history and differential expression regulation

    DEFF Research Database (Denmark)

    Lafont, Anne Gaëlle; Rousseau, Karine; Tomkiewicz, Jonna

    2016-01-01

    Estrogens interact with classical intracellular nuclear receptors (ESR), and with G-coupled membrane receptors (GPER). In the eel, we identified three nuclear (ESR1, ESR2a, ESR2b) and two membrane (GPERa, GPERb) estrogen receptors. Duplicated ESR2 and GPER were also retrieved in most extant teleo...

  17. Estrogen receptor alpha gene polymorphism and endometrial cancer risk – a case-control study

    International Nuclear Information System (INIS)

    Wedrén, Sara; Stiger, Fredrik; Persson, Ingemar; Baron, John A; Weiderpass, Elisabete; Lovmar, Lovisa; Humphreys, Keith; Magnusson, Cecilia; Melhus, Håkan; Syvänen, Ann-Christine; Kindmark, Andreas; Landegren, Ulf; Fermér, Maria Lagerström

    2008-01-01

    Estrogen is an established endometrial carcinogen. One of the most important mediators of estrogenic action is the estrogen receptor alpha. We have investigated whether polymorphic variation in the estrogen receptor alpha gene (ESR1) is associated with endometrial cancer risk. In 702 cases with invasive endometrial cancer and 1563 controls, we genotyped five markers in ESR1 and used logistic regression models to estimate odds ratios (OR) and 95 percent confidence intervals (CI). We found an association between rs2234670, rs2234693, as well as rs9340799, markers in strong linkage disequilibrium (LD), and endometrial cancer risk. The association with rs9340799 was the strongest, OR 0.75 (CI 0.60–0.93) for heterozygous and OR 0.53 (CI 0.37–0.77) for homozygous rare compared to those homozygous for the most common allele. Haplotype models did not fit better to the data than single marker models. We found that intronic variation in ESR1 was associated with endometrial cancer risk

  18. Estrogenic and anti-estrogenic influences in cultured brown trout hepatocytes: Focus on the expression of some estrogen and peroxisomal related genes and linked phenotypic anchors

    Energy Technology Data Exchange (ETDEWEB)

    Madureira, Tânia Vieira, E-mail: tvmadureira@icbas.up.pt [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), U.Porto—University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Institute of Biomedical Sciences Abel Salazar, U.Porto (ICBAS)—University of Porto, Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto (Portugal); Malhão, Fernanda; Pinheiro, Ivone; Lopes, Célia; Ferreira, Nádia [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), U.Porto—University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Institute of Biomedical Sciences Abel Salazar, U.Porto (ICBAS)—University of Porto, Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto (Portugal); Urbatzka, Ralph [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), U.Porto—University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Castro, L. Filipe C. [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), U.Porto—University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Faculty of Sciences (FCUP), U.Porto—University of Porto, Department of Biology, Rua do Campo Alegre, P 4169-007 Porto (Portugal); Rocha, Eduardo [Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), U.Porto—University of Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Institute of Biomedical Sciences Abel Salazar, U.Porto (ICBAS)—University of Porto, Laboratory of Histology and Embryology, Department of Microscopy, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto (Portugal)

    2015-12-15

    Highlights: • Evidence of crosstalk between estrogens and peroxisomal pathways in brown trout. • VtgA and ERα mRNA levels increased after 1, 10 and 50 μM of ethinylestradiol (EE2). • ERβ-1, catalase and urate oxidase mRNA levels decreased after estrogenic stimuli. • Estrogenic effects in VtgA, ERα and Uox mRNA levels were reverted by ICI 182,780. • Immunofluorescence/electron microscopy shows smaller peroxisomes after 50 μM of EE2. - Abstract: Estrogens, estrogenic mimics and anti-estrogenic compounds are known to target estrogen receptors (ER) that can modulate other nuclear receptor signaling pathways, such as those controlled by the peroxisome proliferator-activated receptor (PPAR), and alter organelle (inc. peroxisome) morphodynamics. By using primary isolated brown trout (Salmo trutta f. fario) hepatocytes after 72 and 96 h of exposure we evaluated some effects in selected molecular targets and in peroxisomal morphological features caused by: (1) an ER agonist (ethinylestradiol—EE2) at 1, 10 and 50 μM; (2) an ER antagonist (ICI 182,780) at 10 and 50 μM; and (3) mixtures of both (Mix I—10 μM EE2 and 50 μM ICI; Mix II—1 μM EE2 and 10 μM ICI and Mix III—1 μM EE2 and 50 μM ICI). The mRNA levels of the estrogenic targets (ERα, ERβ-1 and vitellogenin A—VtgA) and the peroxisome structure/function related genes (catalase, urate oxidase—Uox, 17β-hydroxysteroid dehydrogenase 4—17β-HSD4, peroxin 11α—Pex11α and PPARα) were analyzed by real-time polymerase chain reaction (RT-PCR). Stereology combined with catalase immunofluorescence revealed a significant reduction in peroxisome volume densities at 50 μM of EE2 exposure. Concomitantly, at the same concentration, electron microscopy showed smaller peroxisome profiles, exacerbated proliferation of rough endoplasmic reticulum, and a generalized cytoplasmic vacuolization of hepatocytes. Catalase and Uox mRNA levels decreased in all estrogenic stimuli conditions. VtgA and ERα m

  19. Estrogenic and anti-estrogenic influences in cultured brown trout hepatocytes: Focus on the expression of some estrogen and peroxisomal related genes and linked phenotypic anchors

    International Nuclear Information System (INIS)

    Madureira, Tânia Vieira; Malhão, Fernanda; Pinheiro, Ivone; Lopes, Célia; Ferreira, Nádia; Urbatzka, Ralph; Castro, L. Filipe C.; Rocha, Eduardo

    2015-01-01

    Highlights: • Evidence of crosstalk between estrogens and peroxisomal pathways in brown trout. • VtgA and ERα mRNA levels increased after 1, 10 and 50 μM of ethinylestradiol (EE2). • ERβ-1, catalase and urate oxidase mRNA levels decreased after estrogenic stimuli. • Estrogenic effects in VtgA, ERα and Uox mRNA levels were reverted by ICI 182,780. • Immunofluorescence/electron microscopy shows smaller peroxisomes after 50 μM of EE2. - Abstract: Estrogens, estrogenic mimics and anti-estrogenic compounds are known to target estrogen receptors (ER) that can modulate other nuclear receptor signaling pathways, such as those controlled by the peroxisome proliferator-activated receptor (PPAR), and alter organelle (inc. peroxisome) morphodynamics. By using primary isolated brown trout (Salmo trutta f. fario) hepatocytes after 72 and 96 h of exposure we evaluated some effects in selected molecular targets and in peroxisomal morphological features caused by: (1) an ER agonist (ethinylestradiol—EE2) at 1, 10 and 50 μM; (2) an ER antagonist (ICI 182,780) at 10 and 50 μM; and (3) mixtures of both (Mix I—10 μM EE2 and 50 μM ICI; Mix II—1 μM EE2 and 10 μM ICI and Mix III—1 μM EE2 and 50 μM ICI). The mRNA levels of the estrogenic targets (ERα, ERβ-1 and vitellogenin A—VtgA) and the peroxisome structure/function related genes (catalase, urate oxidase—Uox, 17β-hydroxysteroid dehydrogenase 4—17β-HSD4, peroxin 11α—Pex11α and PPARα) were analyzed by real-time polymerase chain reaction (RT-PCR). Stereology combined with catalase immunofluorescence revealed a significant reduction in peroxisome volume densities at 50 μM of EE2 exposure. Concomitantly, at the same concentration, electron microscopy showed smaller peroxisome profiles, exacerbated proliferation of rough endoplasmic reticulum, and a generalized cytoplasmic vacuolization of hepatocytes. Catalase and Uox mRNA levels decreased in all estrogenic stimuli conditions. VtgA and ERα m

  20. Caffeine, Adenosine Receptors and Estrogen in Toxin Models of Parkinson's Disease

    National Research Council Canada - National Science Library

    Schwarzschild, Michael A; Xu, Kui

    2008-01-01

    Continued progress has been made toward each of the Specific Aims (SAs) 1 and 2 (SA 3 completed) of our research project, Caffeine, adenosine receptors and estrogen in toxin models of Parkinson's disease...

  1. Characterization of an estrogen-responsive element implicated in regulation of the rainbow trout estrogen receptor gene.

    Science.gov (United States)

    Le Dréan, Y; Lazennec, G; Kern, L; Saligaut, D; Pakdel, F; Valotaire, Y

    1995-08-01

    We previously reported that the expression of the rainbow trout estrogen receptor (rtER) gene is markedly increased by estradiol (E2). In this paper, we have used transient transfection assays with reporter plasmids expressing chloramphenicol acetyl transferase (CAT), linked to 5' flanking regions of the rtER gene promoter, to identify cis-elements responsible for E2 inducibility. Deletion analysis localized an estrogen-responsive element (ERE), at position +242, with one mutation on the first base compared with the consensus sequence. This element confers estrogen responsiveness to CAT reporter linked to both the herpes simplex virus thymidine kinase promoter and the homologous rtER promoter. Moreover, using a 0.2 kb fragment of the rtER promoter encompassing the ERE and the rtER DNA binding domain obtained from a bacterial expression system, DNase I footprinting experiments demonstrated a specific protection covering 20 bp (+240/+260) containing the ERE sequence. Based on these studies, we believe that this ERE sequence, identified in the rtER gene promoter, may be a major cis-acting element involved in the regulation of the gene by estrogen.

  2. The Estrogen Receptor-β Expression in De Quervain’s Disease

    Directory of Open Access Journals (Sweden)

    Po-Chuan Shen

    2015-11-01

    Full Text Available Stenosing tenosynovitis of the first dorsal compartment of the wrist (a.k.a. de Quervain’s disease is common but how estrogen is involved is still unknown. We previously reported that inflammation was involved in the pathogenesis of this ailment. In the present study, we extended our investigation of estrogen receptor (ER-β expression to determine whether estrogen is involved in the pathogenesis of de Quervain’s. Intraoperative retinaculum samples were collected from 16 patients with the ailment. Specimens were histologically graded by collagen structure and immunohistochemically evaluated by quantifying the expression of ER-β, interleukin (IL-1β and IL-6 (inflammatory cytokines, cyclooxygenase (COX-2 (an inflammatory enzyme, and vascular endothelial growth factor (VEGF, and Von Willebrand’s factor (vWF. De Quervain’s occurs primarily in women. The female:male ratio in our study was 7:1. We found that ER-β expression in the retinaculum was positively correlated with disease grade and patient age. Additionally, disease severity was associated with inflammatory factors—IL-1β and IL-6, COX-2, and VEGF and vWF in tenosynovial tissue. The greater the levels of ER-β expression, tissue inflammation, and angiogenesis are, the more severe de Quervain’s disease is. ER-β might be a useful target for novel de Quervain’s disease therapy.

  3. Estradiol-induced desensitization of 5-HT1A receptor signaling in the paraventricular nucleus of the hypothalamus is independent of estrogen receptor-beta.

    Science.gov (United States)

    Rossi, Dania V; Dai, Ying; Thomas, Peter; Carrasco, Gonzalo A; DonCarlos, Lydia L; Muma, Nancy A; Li, Qian

    2010-08-01

    Estradiol regulates serotonin 1A (5-HT(1A)) receptor signaling. Since desensitization of 5-HT(1A) receptors may be an underlying mechanism by which selective serotonin reuptake inhibitors (SSRIs) mediate their therapeutic effects and combining estradiol with SSRIs enhances the efficacy of the SSRIs, it is important to determine which estrogen receptors are capable of desensitizating 5-HT(1A) receptor function. We previously demonstrated that selective activation of the estrogen receptor, GPR30, desensitizes 5-HT(1A) receptor signaling in rat hypothalamic paraventricular nucleus (PVN). However, since estrogen receptor-beta (ERbeta), is highly expressed in the PVN, we investigated the role of ERbeta in estradiol-induced desensitization of 5-HT(1A) receptor signaling. We first showed that a selective ERbeta agonist, diarylpropionitrile (DPN) has a 100-fold lower binding affinity than estradiol for GPR30. Administration of DPN did not desensitize 5-HT(1A) receptor signaling in rat PVN as demonstrated by agonist-stimulated hormone release. Second, we used a recombinant adenovirus containing ERbeta siRNAs to decrease ERbeta expression in the PVN. Reductions in ERbeta did not alter the estradiol-induced desensitization of 5-HT(1A) receptor signaling in oxytocin cells. In contrast, in animals with reduced ERbeta, estradiol administration, instead of producing desensitization, augmented the ACTH response to a 5-HT(1A) agonist. Combined with the results from the DPN treatment experiments, desensitization of 5-HT(1A) receptor signaling does not appear to be mediated by ERbeta in oxytocin cells, but that ERbeta, together with GPR30, may play a complex role in central regulation of 5-HT(1A)-mediated ACTH release. Determining the mechanisms by which estrogens induce desensitization may aid in the development of better treatments for mood disorders. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Estrogen and progesterone receptor testing in breast carcinoma: concordance of results between local and reference laboratories in Brazil

    Directory of Open Access Journals (Sweden)

    Sheila Cristina Lordelo Wludarski

    Full Text Available CONTEXT AND OBJECTIVE: Breast cancer accounts for approximately one quarter of all cancers in females. Estrogen and progesterone receptor testing has become an essential part of the clinical evaluation of breast carcinoma patients, and accurate results are critical in identifying patients who may benefit from hormone therapy. The present study had the aim of investigating the concordance of the results from hormone receptor tests between a reference laboratory and local (or community laboratories in Brazil. DESIGN AND SETTING: Retrospective study at a reference pathology laboratory. METHODS: The concordance in the results from hormone receptor tests between a reference laboratory and 146 local laboratories in Brazil was compared in relation to 500 invasive breast carcinoma cases, using immunohistochemistry. RESULTS: There was concordance in 89.4% (447/500 cases and 85.0% (425/500 cases of the results from estrogen (κ = 0.744, P < 0.001 and progesterone (κ = 0.688, P < 0.001 receptor tests, respectively, between local and reference laboratories. This was similar to findings in other countries. The false negative rates from estrogen and progesterone receptor tests in local laboratories were 8.7% and 14.4%, respectively. The false positive rates from estrogen and progesterone receptor tests in local laboratories were 15.5% and 16.0%, respectively. CONCLUSION: Technical and result interpretation issues may explain most of the discordances in hormone receptor testing in local laboratories. Validation of estrogen and progesterone receptor tests at local laboratories, with rigorous quality control measures, is strongly recommended in order to avoid erroneous treatment of breast cancer patients.

  5. Selective estrogen receptor modulators as brain therapeutic agents

    OpenAIRE

    Arévalo, María Ángeles; Santos-Galindo, María; Lagunas, Natalia; Azcoitia, I.; García-Segura, Luis M.

    2011-01-01

    Selective estrogen receptor modulators (SERMs), used for the treatment of breast cancer, osteoporosis, and menopausal symptoms, affect the nervous system. Some SERMs trigger neuroprotective mechanisms and reduce neural damage in different experimental models of neural trauma, brain inflammation, neurodegenerative diseases, cognitive impairment, and affective disorders. New SERMs with specific actions on neurons and glial cells may represent promising therapeutic tools for the brain. © 2011 So...

  6. Ketamine and ketamine metabolites as novel estrogen receptor ligands: Induction of cytochrome P450 and AMPA glutamate receptor gene expression.

    Science.gov (United States)

    Ho, Ming-Fen; Correia, Cristina; Ingle, James N; Kaddurah-Daouk, Rima; Wang, Liewei; Kaufmann, Scott H; Weinshilboum, Richard M

    2018-04-03

    Major depressive disorder (MDD) is the most common psychiatric illness worldwide, and it displays a striking sex-dependent difference in incidence, with two thirds of MDD patients being women. Ketamine treatment can produce rapid antidepressant effects in MDD patients, effects that are mediated-at least partially-through glutamatergic neurotransmission. Two active metabolites of ketamine, (2R,6R)-hydroxynorketamine (HNK) and (2S,6S)-HNK, also appear to play a key role in ketamine's rapid antidepressant effects through the activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors. In the present study, we demonstrated that estrogen plus ketamine or estrogen plus active ketamine metabolites displayed additive effects on the induction of the expression of AMPA receptor subunits. In parallel, the expression of estrogen receptor alpha (ERα) was also significantly upregulated. Even more striking, radioligand binding assays demonstrated that [ 3 H]-ketamine can directly bind to ERα (K D : 344.5 ± 13 nM). Furthermore, ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites displayed similar affinity for ERα (IC 50 : 2.31 ± 0.1, 3.40 ± 0.2, and 3.53 ± 0.2 µM, respectively) as determined by [ 3 H]-ketamine displacement assays. Finally, induction of AMPA receptors by either estrogens or ketamine and its metabolites was lost when ERα was knocked down or silenced pharmacologically. These results suggest a positive feedback loop by which estrogens can augment the effects of ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites on the ERα-induced transcription of CYP2A6 and CYP2B6, estrogen inducible enzymes that catalyze ketamine's biotransformation to form the two active metabolites. These observations provide novel insight into ketamine's molecular mechanism(s) of action and have potential implications for the treatment of MDD. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Automated synthesis of the estrogen receptors imaging agent 18F-FES

    International Nuclear Information System (INIS)

    Guo Shen; Chen Guobao; Dai Hongfeng; Lin Meifu; Chen Wenxin

    2011-01-01

    Objective: 18 F-16α-17β-fluoroestradiol ( 18 F-FES), an estrogen receptors imaging agent, is synthesized with Tracerlab FX FN system. Methods: 18 F-FES is obtained by two steps reactions, including the nucleophilic displacement reaction of no-carrier-added 18 F-fluoride with 3-O-methoxymethyl-16, 17-O-sulfuryl-16-epiesteriol, then the intermediate is evaporated and hydrolyzed with HCI and finally gives 18 F-FES. Results: The synthesis of 18 F-FES can be completed in about 80 min.The radiochemical yield and radio-chemical purity are about 10% and 95% respectively. Conclusion: The procedure of synthesis is simple and automatical. 18 F-FES has an extremely low toxicity, which suggests that 18 F-FES may be a safe, a nd effective estrogen receptors imaging agent. (authors)

  8. Abiraterone acetate, exemestane or the combination in postmenopausal patients with estrogen receptor-positive metastatic breast cancer ?

    OpenAIRE

    O'Shaughnessy, J.; Campone, M.; Brain, E.; Neven, P.; Hayes, D.; Bondarenko, I.; Griffin, T. W.; Martin, J.; De Porre, P.; Kheoh, T.; Yu, M. K.; Peng, W.; Johnston, S.

    2015-01-01

    Background Androgen receptor (AR) signaling and incomplete inhibition of estrogen signaling may contribute to metastatic breast cancer (MBC) resistance to a nonsteroidal aromatase inhibitor (NSAI; letrozole or anastrozole). We assessed whether combined inhibition of androgen biosynthesis with abiraterone acetate plus prednisone and estradiol synthesis with exemestane (E) may be of clinical benefit to postmenopausal patients with NSAI-pretreated estrogen receptor-positive (ER+) MBC. Patients a...

  9. Regulation of the intronic promoter of rat estrogen receptor alpha gene, responsible for truncated estrogen receptor product-1 expression.

    Science.gov (United States)

    Schausi, Diane; Tiffoche, Christophe; Thieulant, Marie-Lise

    2003-07-01

    We have characterized the intronic promoter of the rat estrogen receptor (ER) alpha gene, responsible for the lactotrope-specific truncated ER product (TERP)-1 isoform expression. Transcriptional regulation was investigated by transient transfections using 5'-deletion constructs. TERP promoter constructs were highly active in MMQ cells, a pure lactotrope cell line, whereas a low basal activity was detected in alphaT3-1 gonadotrope cells or in COS-7 monkey kidney cells. Serial deletion analysis revealed that 1) a minimal -693-bp region encompassing the TATA box is sufficient to allow lactotrope-specific expression; 2) the promoter contains strong positive cis-acting elements both in the distal and proximal regions, and 3) the region spanning the -1698/-1194 region includes repressor elements. Transient transfection studies, EMSAs, and gel shifts demonstrated that estrogen activates the TERP promoter via an estrogen-responsive element (ERE1) located within the proximal region. Mutation of ERE1 site completely abolishes the estradiol-dependent transcription, indicating that ERE1 site is sufficient to confer estrogen responsiveness to TERP promoter. In addition, ERalpha action was synergized by transfection of the pituitary-specific factor Pit-1. EMSAs showed that a single Pit-1 DNA binding element in the vicinity of the TATA box is sufficient to confer response by the TERP promoter. In conclusion, we demonstrated, for the first time, that TERP promoter regulation involves ERE and Pit-1 cis-elements and corresponding trans-acting factors, which could play a role in the physiological changes that occur in TERP-1 transcription in lactotrope cells.

  10. Distinct expression of three estrogen receptors in response to bisphenol A and nonylphenol in male Nile tilapias (Oreochromis niloticus).

    Science.gov (United States)

    Huang, Weiren; Zhang, Yong; Jia, Xiaoping; Ma, Xilan; Li, Shuisheng; Liu, Yun; Zhu, Pei; Lu, Danqi; Zhao, Huihong; Luo, Wenna; Yi, Shibai; Liu, Xiaochun; Lin, Haoran

    2010-06-01

    Environmental estrogens, such as bisphenol A (BisA) and nonylphenol (NP), have been shown to affect the estrogen receptor (ER) expression and induce male reproductive abnormalities. To elucidate molecular mechanisms of action of xenoestrogenic chemicals on the expression of estrogen receptors in the testes of Nile tilapia (Oreochromis niloticus), three full-length cDNAs respectively encoding ntERalpha, ntERbeta1 and ntERbeta2 were cloned from testes. The amino acid sequences of ntERalpha, ntERbeta1 and ntERbeta2 showed a high degree of similarity to the relevant fish species. Tissue-specific expression study showed that three receptors were highly expressed in pituitary, liver, testis, kidney and intestine tissues. The ntERalpha, ntERbeta1 and ntERbeta2 mRNA expressions were significantly higher at the sexual early recrudescing stage than at other recrudesced stages. After being exposed to xenoestrogens from weeks 2 to 4, the ntERalpha mRNA levels were increased significantly in testes after NP treatment at all sampling times or after 4 weeks of exposure to BPA. The ntERbeta1 mRNA levels remained unchanged, while a significant decrease of the ntERbeta2 mRNA level was observed in testes after exposure to NP and BPA. The present study demonstrates that the regulation of all three ntER subtypes in testes may act via different molecular mechanisms of exposure to NP and BPA.

  11. Estrogen-Related Receptors and the control of bone cell fate.

    Science.gov (United States)

    Carnesecchi, Julie; Vanacker, Jean-Marc

    2016-09-05

    Bone loss is naturally occurring in aging males and females and exacerbated in the latter after menopause, altogether leading to cumulative skeleton fragility and increased fracture risk. Two types of therapeutic strategies can be envisioned to counteract age- or menopause-associated bone loss, aiming at either reducing bone resorption exerted by osteoclasts or, alternatively, promoting bone formation by osteoblasts. We here summarize data suggesting that inhibition of the Estrogen-Related Receptors α and/or γ could promote bone formation and compensate for bone loss induced by ageing or estrogen-deficiency. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Estrogen receptor-alpha-immunoreactive neurons in the periaqueductal gray of the adult ovariectomized female cat

    NARCIS (Netherlands)

    VanderHorst, Veronique G.J.M.; Meijer, Ellie; Schasfoort, Fabienne C.; Leeuwen, Fred van; Holstege, Gert

    1998-01-01

    Anatomical and physiological studies in rodent and cat have shown that distinct parts of the midbrain periaqueductal gray (FAG) are important for the estrogen dependent, female reproductive behavior. The present study gives a detailed overview of the estrogen receptor-alpha-immunoreactive (ER-IR)

  13. The RNA binding protein HuR differentially regulates unique subsets of mRNAs in estrogen receptor negative and estrogen receptor positive breast cancer

    Directory of Open Access Journals (Sweden)

    Chen Jing

    2010-04-01

    Full Text Available Abstract Background The discordance between steady-state levels of mRNAs and protein has been attributed to posttranscriptional control mechanisms affecting mRNA stability and translation. Traditional methods of genome wide microarray analysis, profiling steady-state levels of mRNA, may miss important mRNA targets owing to significant posttranscriptional gene regulation by RNA binding proteins (RBPs. Methods The ribonomic approach, utilizing RNA immunoprecipitation hybridized to microarray (RIP-Chip, provides global identification of putative endogenous mRNA targets of different RBPs. HuR is an RBP that binds to the AU-rich elements (ARE of labile mRNAs, such as proto-oncogenes, facilitating their translation into protein. HuR has been shown to play a role in cancer progression and elevated levels of cytoplasmic HuR directly correlate with increased invasiveness and poor prognosis for many cancers, including those of the breast. HuR has been described to control genes in several of the acquired capabilities of cancer and has been hypothesized to be a tumor-maintenance gene, allowing for cancers to proliferate once they are established. Results We used HuR RIP-Chip as a comprehensive and systematic method to survey breast cancer target genes in both MCF-7 (estrogen receptor positive, ER+ and MDA-MB-231 (estrogen receptor negative, ER- breast cancer cell lines. We identified unique subsets of HuR-associated mRNAs found individually or in both cell types. Two novel HuR targets, CD9 and CALM2 mRNAs, were identified and validated by quantitative RT-PCR and biotin pull-down analysis. Conclusion This is the first report of a side-by-side genome-wide comparison of HuR-associated targets in wild type ER+ and ER- breast cancer. We found distinct, differentially expressed subsets of cancer related genes in ER+ and ER- breast cancer cell lines, and noted that the differential regulation of two cancer-related genes by HuR was contingent upon the cellular

  14. Advances in breast cancer treatment and prevention: preclinical studies on aromatase inhibitors and new selective estrogen receptor modulators (SERMs)

    International Nuclear Information System (INIS)

    Schiff, Rachel; Chamness, Gary C; Brown, Powel H

    2003-01-01

    Intensive basic and clinical research over the past 20 years has yielded crucial molecular understanding into how estrogen and the estrogen receptor act to regulate breast cancer and has led to the development of more effective, less toxic, and safer hormonal therapy agents for breast cancer management and prevention. Selective potent aromatase inhibitors are now challenging the hitherto gold standard of hormonal therapy, the selective estrogen-receptor modulator tamoxifen. Furthermore, new selective estrogen-receptor modulators such as arzoxifene, currently under clinical development, offer the possibility of selecting one with a more ideal pharmacological profile for treatment and prevention of breast cancer. Two recent studies in preclinical model systems that evaluate mechanisms of action of these new drugs and suggestions about their optimal clinical use are discussed

  15. Assessment of estrogenic activity in some common essential oil constituents.

    Science.gov (United States)

    Howes, M-J R; Houghton, P J; Barlow, D J; Pocock, V J; Milligan, S R

    2002-11-01

    Estrogenic responses have not only been associated with endocrine function, but also with cognitive function. Several studies have indicated that estrogen replacement therapy has favourable effects on cognition, and may have potential in the prevention and treatment of Alzheimer's disease. Thus, ligands for the estrogen receptor, that have a better efficacy and adverse-effect profile than drugs currently available, require investigation. This study was undertaken to investigate the potential estrogenic activity of a number of essential oil constituents. Initially, estrogenic activity was determined by a sensitive and specific bioassay using recombinant yeast cells expressing the human estrogen receptor. At high concentrations, estrogenic activity was detected for citral (geranial and neral), geraniol, nerol and trans-anethole, while eugenol showed anti-estrogenic activity. Molecular graphics studies were undertaken to identify the possible mechanisms for the interaction of geranial, neral, geraniol, nerol and eugenol with the ligand-binding domain of the estrogen alpha-receptor, using the computer program HyperChem. Citral, geraniol, nerol and eugenol were also able to displace [(3)H]17beta-estradiol from isolated alpha- and beta-human estrogen receptors, but none of these compounds showed estrogenic or anti-estrogenic activity in the estrogen-responsive human cell line Ishikawa Var I at levels below their cytotoxic concentrations, and none showed activity in a yeast screen for androgenic and anti-androgenic activity. The potential in-vivo estrogenic effects of citral and geraniol were examined in ovariectomized mice, but neither compound showed any ability to stimulate the characteristic estrogenic responses of uterine hypertrophy or acute increase in uterine vascular permeability. These results show that very high concentrations of some commonly used essential oil constituents appear to have the potential to interact with estrogen receptors, although the

  16. The assay of estrogen receptors in three components of human breast cancer tissue

    International Nuclear Information System (INIS)

    Lu Hanping; Gui Zhining

    1992-01-01

    The binding capacities of estrogen receptors in nuclear matrix, nuclei and cytosol of human breast cancer tissue (EmR, EnR, EcR) were estimated with radioligand binding assay of receptors. The average B max values of these components in 21 breast cancer specimens are 417.54 ± 170.95, 147.75 ± 98.32, 7.34 ± 5.33 fmol/mg protein, and those in 10 normal breast tissue specimens are 42.33 ± 8.49, 25.05 ± 7.81, 5.91 ± 2.28 fmol/mg protein. Comparing the cancer and normal breast tissues, there is significant difference in B max values of EmR and EnR (P max values of EcR (P > 0.10). The EmR/EnR value of 21 breast cancer tissue is 0.65 ± 0.10, and that of 10 normal breast tissue is 0.42 ± 0.04. There is statistical difference between the cancer and normal. 10 of 13 (77%) patients, who are EcR-positive, have higher EmR/EnR values (≥0.50). The results suggest that estrogen receptors are mainly located at the nuclear matrix, ER levels in nucleus, especially in nuclear matrix of breast cancer tissue are valuable parameters and may be useful for predicting whether the patient will be responsible to endocrine therapy

  17. Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Ruyue; Fang, Liaoqiong [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Xing, Ruoxi [Institute of Life Science, Chongqing Medical University, Chongqing 400016 (China); Xiong, Yu [Department of Obstetrics and Gynecology, Chongqing Hifu Hospital, Chongqing 401121 (China); Fang, Liaoqiong, E-mail: lqfang06@163.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Wang, Zhibiao, E-mail: wangzb@cqmu.edu.cn [State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and The Ministry of Science and Technology, Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China)

    2015-12-04

    Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERα and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E{sub 2}) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E{sub 2} concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights: • In both

  18. Estrogen receptor beta, a possible tumor suppressor involved in ovarian carcinogenesis

    Science.gov (United States)

    Lazennec, Gwendal

    2006-01-01

    Ovarian cancer is one of the leading cause of death from gynecological tumors in women. Several lines of evidence suggest that estrogens may play an important role in ovarian carcinogenesis, through their receptors, ERα and ERβ. Interestingly, malignant ovarian tumors originating from epithelial surface constitute about 90% of ovarian cancers and expressed low levels of ERβ, compared to normal tissues. In addition, restoration of ERβ in ovarian cancer cells, leads to strong inhibition of their proliferation and invasion, while apoptosis is enhanced. In this manuscript, recent data suggesting a possible tumor-suppressor role for ERβ in ovarian carcinogenesis are discussed. PMID:16399219

  19. MIBE acts as antagonist ligand of both estrogen receptor α and GPER in breast cancer cells.

    Science.gov (United States)

    Lappano, Rosamaria; Santolla, Maria Francesca; Pupo, Marco; Sinicropi, Maria Stefania; Caruso, Anna; Rosano, Camillo; Maggiolini, Marcello

    2012-01-17

    The multiple biological responses to estrogens are mainly mediated by the classical estrogen receptors ERα and ERβ, which act as ligand-activated transcription factors. ERα exerts a main role in the development of breast cancer; therefore, the ER antagonist tamoxifen has been widely used although its effectiveness is limited by de novo and acquired resistance. Recently, GPR30/GPER, a member of the seven-transmembrane G protein-coupled receptor family, has been implicated in mediating the effects of estrogens in various normal and cancer cells. In particular, GPER triggered gene expression and proliferative responses induced by estrogens and even ER antagonists in hormone-sensitive tumor cells. Likewise, additional ER ligands showed the ability to bind to GPER eliciting promiscuous and, in some cases, opposite actions through the two receptors. We synthesized a novel compound (ethyl 3-[5-(2-ethoxycarbonyl-1-methylvinyloxy)-1-methyl-1H-indol-3-yl]but-2-enoate), referred to as MIBE, and investigated its properties elicited through ERα and GPER in breast cancer cells. Molecular modeling, binding experiments and functional assays were performed in order to evaluate the biological action exerted by MIBE through ERα and GPER in MCF7 and SkBr3 breast cancer cells. MIBE displayed the ability to act as an antagonist ligand for ERα and GPER as it elicited inhibitory effects on gene transcription and growth effects by binding to both receptors in breast cancer cells. Moreover, GPER was required for epidermal growth factor receptor (EGFR) and ERK activation by EGF as ascertained by using MIBE and performing gene silencing experiments. Our findings provide novel insights on the functional cross-talk between GPER and EGFR signaling. Furthermore, the exclusive antagonistic activity exerted by MIBE on ERα and GPER could represent an innovative pharmacological approach targeting breast carcinomas which express one or both receptors at the beginning and/or during tumor

  20. Estrogen receptor binding radiopharmaceuticals: II. Tissue distribution of 17 α-methylestradiol in normal and tumor-bearing rats

    International Nuclear Information System (INIS)

    Feenstra, A.; Vaalburg, W.; Nolten, G.M.J.; Reiffers, S.; Talma, A.G.; Wiegman, T.; van der Molen, H.D.; Woldring, M.G.

    1983-01-01

    Tritiated 17α-methylestradiol was synthesized to investigate the potential of the carbon-11-labeled analog as an estrogen-receptor-binding radiopharmaceutical. In vitro, 17α-methylestradiol is bound with high affinity to the cytoplasmic estrogen receptor from rabbit uterus (K/sub d/ = 1.96 x 10 -10 M), and it sediments as an 8S hormone-receptor complex in sucrose gradients. The compound shows specific uptake in the uterus of the adult rat, within 1 h after injection. In female rats bearing DMBA-induced tumors, specific uterine and tumor uptakes were observed, although at 30 min the tumor uptake was only 23 to 30% of the uptake in the uterus. Tritiated 17α-methylestradiol with a specific activity of 6 Ci/mmole showed a similar tissue distribution. Our results indicate that a 17 α-methylestradiol is promising as an estrogen-receptor-binding radiopharmaceutical

  1. Estrogens of multiple classes and their role in mental health disease mechanisms

    Directory of Open Access Journals (Sweden)

    Cheryl S Watson

    2010-06-01

    Full Text Available Cheryl S Watson1, Rebecca A Alyea1, Kathryn A Cunningham2, Yow-Jiun Jeng11Department of Biochemistry and Molecular Biology, 2Department of Pharmacology and Toxicology, Univ of Texas Medical Branch, Galveston, TX, USAAbstract: Gender and sex hormones can influence a variety of mental health states, including mood, cognitive development and function, and vulnerability to neurodegenerative diseases and brain damage. Functions of neuronal cells may be altered by estrogens depending upon the availability of different physiological estrogenic ligands; these ligands and their effects vary with life stages, the genetic or postgenetic regulation of receptor levels in specific tissues, or the intercession of competing nonphysiological ligands (either intentional or unintentional, beneficial to health or not. Here we review evidence for how different estrogens (physiological and environmental/dietary, acting via different estrogen receptor subtypes residing in alternative subcellular locations, influence brain functions and behavior. We also discuss the families of receptors and transporters for monoamine neurotransmitters and how they may interact with the estrogenic signaling pathways.Keywords: estrogen receptor α, estrogen receptor β, GPR30, GPER, xenoestrogens, phytoestrogens, transporters, brain function, neurotransmitter receptors

  2. Selective estrogen receptor modulators (SERM: A new choice for postmenopausal women and physicians who worry on cancer

    Directory of Open Access Journals (Sweden)

    Ali Baziad

    2001-09-01

    Full Text Available The postmenopausal state is characterized by the cessation of menstruation, loss of ovarian function, and a dramatic decrease in the level of circulating estrogen. This state of estrogen deficiency contributes to the acceleration of several age-related health problems in women, including cardiovascular disease, osteoporosis, and dementia. Estrogen replacement is clearly effective in the short-term and long-term treatment and prevention of postmenopausal symptoms. However, until now, the amount of HRT user is still very low. Fear of breast cancer and endometrial cancer are the most common concern in using hormone replacement therapy (HRT, although the relationship between long-term HRT and breast cancer remains controversial. For physicians or patients, who worry on cancer, the ideal drug is now available i.e. the selective estrogen receptor modulators (SERM, with the generic name raloxifine. (Med J Indones 2001; 10: 187-90Keywords: HRT, raloxifine, osteoporosis, CVD, tamoxifen

  3. Estrogen receptor-alpha immunoreactivity in parasympathetic preganglionic neurons innervating the bladder in the adult ovariectomized cat

    NARCIS (Netherlands)

    van der Horst, V. G. J. M.; Meijer, E; Holstege, G

    2001-01-01

    Estrogen affects autonomic functions such as micturition. The sacral cord is important in the control of micturition and contains numerous estrogen receptor-alpha immnoreactive (ER-alpha IR) neurons. Therefore, the present double labeling study examines whether sacral parasympathetic preganglionic

  4. Gender-specific effects of endogenous testosterone: female alpha-estrogen receptor-deficient C57Bl/6J mice develop glomerulosclerosis.

    Science.gov (United States)

    Elliot, S J; Berho, M; Korach, K; Doublier, S; Lupia, E; Striker, G E; Karl, M

    2007-08-01

    Young female mice on a C57Bl/6J (B6) background are considered glomerulosclerosis (GS)-resistant but aging B6 mice develop mild GS. Estrogen deficiency accelerates while estrogen replacement retards GS in young sclerosis-prone oligosyndactyly mutant mice on an ROP background. To explore the effects of sex hormones on glomerular structure and function in the context of gender and genetic background, we studied mice in which the estrogen-receptor (ER) genes alpha- or -beta were deleted (alpha- or betaER knockout (KO)) and crossed into the B6 background. We also studied ovariectomized (Ovx) B6 mice given testosterone. Male and female betaERKO and male alphaERKO mice had no glomerular dysfunction at 9 months of age; however, alphaERKO female mice displayed albuminuria and GS. Ovx prevented glomerular dysfunction in alphaERKO female mice by eliminating endogenous testosterone production while exogenous testosterone induced GS in Ovx B6 mice. Androgen receptor (AR) expression and function was found in microdissected glomeruli and cultured mesangial cells. Testosterone compared to placebo increased both AR expression and TGF-beta1 mRNA levels in glomeruli isolated from female B6 mice. Estrogen deficiency had no deleterious effects on the glomeruli in B6 mice. Our study shows that genetic traits strongly influence the GS-promoting effects of estrogen deficiency while testosterone induces GS in a gender-specific manner.

  5. Estrogen inhibits RANKL-stimulated osteoclastic differentiation of human monocytes through estrogen and RANKL-regulated interaction of estrogen receptor-α with BCAR1 and Traf6

    International Nuclear Information System (INIS)

    Robinson, Lisa J.; Yaroslavskiy, Beatrice B.; Griswold, Reed D.; Zadorozny, Eva V.; Guo, Lida; Tourkova, Irina L.; Blair, Harry C.

    2009-01-01

    The effects of estrogen on osteoclast survival and differentiation were studied using CD14-selected mononuclear osteoclast precursors from peripheral blood. Estradiol at ∼ 1 nM reduced RANKL-dependent osteoclast differentiation by 40-50%. Osteoclast differentiation was suppressed 14 days after addition of RANKL even when estradiol was withdrawn after 18 h. In CD14+ cells apoptosis was rare and was not augmented by RANKL or by 17-β-estradiol. Estrogen receptor-α (ERα) expression was strongly down-regulated by RANKL, whether or not estradiol was present. Mature human osteoclasts thus cannot respond to estrogen via ERα. However, ERα was present in CD14+ osteoclast progenitors, and a scaffolding protein, BCAR1, which binds ERα in the presence of estrogen, was abundant. Immunoprecipitation showed rapid (∼ 5 min) estrogen-dependent formation of ERα-BCAR1 complexes, which were increased by RANKL co-treatment. The RANKL-signaling intermediate Traf6, which regulates NF-κB activity, precipitated with this complex. Reduction of NF-κB nuclear localization occurred within 30 min of RANKL stimulation, and estradiol inhibited the phosphorylation of IκB in response to RANKL. Inhibition by estradiol was abolished by siRNA knockdown of BCAR1. We conclude that estrogen directly, but only partially, curtails human osteoclast formation. This effect requires BCAR1 and involves a non-genomic interaction with ERα.

  6. Estrogen inhibits RANKL-stimulated osteoclastic differentiation of human monocytes through estrogen and RANKL-regulated interaction of estrogen receptor-{alpha} with BCAR1 and Traf6

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Lisa J., E-mail: robinsonlj@msx.upmc.edu [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Yaroslavskiy, Beatrice B.; Griswold, Reed D.; Zadorozny, Eva V.; Guo, Lida; Tourkova, Irina L. [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Blair, Harry C. [Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Veteran' s Affairs Medical Center, Pittsburgh, PA 15243 (United States)

    2009-04-15

    The effects of estrogen on osteoclast survival and differentiation were studied using CD14-selected mononuclear osteoclast precursors from peripheral blood. Estradiol at {approx} 1 nM reduced RANKL-dependent osteoclast differentiation by 40-50%. Osteoclast differentiation was suppressed 14 days after addition of RANKL even when estradiol was withdrawn after 18 h. In CD14+ cells apoptosis was rare and was not augmented by RANKL or by 17-{beta}-estradiol. Estrogen receptor-{alpha} (ER{alpha}) expression was strongly down-regulated by RANKL, whether or not estradiol was present. Mature human osteoclasts thus cannot respond to estrogen via ER{alpha}. However, ER{alpha} was present in CD14+ osteoclast progenitors, and a scaffolding protein, BCAR1, which binds ER{alpha} in the presence of estrogen, was abundant. Immunoprecipitation showed rapid ({approx} 5 min) estrogen-dependent formation of ER{alpha}-BCAR1 complexes, which were increased by RANKL co-treatment. The RANKL-signaling intermediate Traf6, which regulates NF-{kappa}B activity, precipitated with this complex. Reduction of NF-{kappa}B nuclear localization occurred within 30 min of RANKL stimulation, and estradiol inhibited the phosphorylation of I{kappa}B in response to RANKL. Inhibition by estradiol was abolished by siRNA knockdown of BCAR1. We conclude that estrogen directly, but only partially, curtails human osteoclast formation. This effect requires BCAR1 and involves a non-genomic interaction with ER{alpha}.

  7. Methylation of the estrogen receptor CpG island distinguishes spontaneous and plutonium-induced tumors from nitrosamine-induced lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Belinsky, S.A.; Baylin, S.B.; Issa, J.J. [Johns Hopkins Univ., Baltimore, MD (United States)

    1995-12-01

    CpG islands located in the promoter region of genes constitute one mechanism for regulating transcription. These islands are normally free of methylation, regardless of the expression state of the gene. Hypermethylation of CpG islands, the addition of a methyl group to the internal cytosine within CpG dinucleotides, can cause silencing of a gene. Hypermethylation has been detected as an early event at specific chromosome loci during the development of colon cancer and represents one mechanism used by neoplatic cells to inactivate tumor suppressor genes. Recent studies have demonstrated this mechanism in inactivation of the VHL tumor suppressor gene in 19% of sporadic renal tumors and the p16 {sup INK4a} tumor suppressor gene in 30% of non-small cell lung cancers. A recent report indicates that the estrogen receptor gene could also be inactivated through methylation. In addition, estrogen receptor CpG island methylation arises as a direct function of age in normal colonic mucosa and is present in virtually all colonic tumors. In cultured colon cancer cells, methylation-associated loss of expression of the estrogen receptor gene results in deregulated growth, suggesting a role for the estrogen receptor in colon cancer development. These results provide further evidence that gene silencing through methylation could be a predominant epigenetic mechanism underlying the development of many different types of cancer. The purpose of the current investigation was to determine whether estrogen receptor CpG island methylation is involved in the development of lung cancer. The frequency for methylation of the estrogen receptor CpG island in rodent lung tumors is summarized.

  8. Estrogen Receptor α Is Crucial in Zearalenone-Induced Invasion and Migration of Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Karolina Kowalska

    2018-02-01

    Full Text Available Zearalenone (ZEA, a mycotoxin produced in the genus Fusarium, binds to estrogen receptors (ER and is therefore regarded as an endocrine disruptor. ZEA has also been found to modulate the proliferation and apoptosis of prostate cancer cells in a dose-dependent manner. This study evaluates whether the effect of a low dose of ZEA (0.1 and 0.001 nM on the invasion and migration of prostate cancer cell line PC3 is associated with ERs expression. The invasion and migration was evaluated by modified Boyden chamber assay, scratch assay, gelatin zymography, Real Time qPCR (RTqPCR and Western blot. The involvement of ERs was evaluated with the selective ER antagonists: estrogen receptor α (ERα antagonist 1,3-bis (4-hydroxyphenyl-4-methyl-5-[4-(2-piperidinylethoxy phenol]-1H-pyrazole dihydrochloride (MPP and estrogen receptor β (ERβ antagonist 4-[2–phenyl-5,7–bis (trifluoromethyl pyrazolo [1,5-a]-pyrimidin-3-yl] phenol (PHTPP. ZEA was found to modulate cell motility dependent on estrogen receptors, particularly ERα. Increased cell migration and invasion were associated with increased MMP-2 and MMP-9 activity as well as the up-regulation of the EMT-associated genes vimentin (VIM, zinc finger E-box-binding homeobox 1/2 (ZEB1/2 and transforming growth factor β 1 (TGFβ1. In conclusion, ZEA might modulate the invasiveness of prostate cancer cells dependently on ERα expression.

  9. Interplay between estrogen receptor and AKT in estradiol-induced alternative splicing.

    Science.gov (United States)

    Bhat-Nakshatri, Poornima; Song, Eun-Kyung; Collins, Nikail R; Uversky, Vladimir N; Dunker, A Keith; O'Malley, Bert W; Geistlinger, Tim R; Carroll, Jason S; Brown, Myles; Nakshatri, Harikrishna

    2013-06-11

    Alternative splicing is critical for generating complex proteomes in response to extracellular signals. Nuclear receptors including estrogen receptor alpha (ERα) and their ligands promote alternative splicing. The endogenous targets of ERα:estradiol (E2)-mediated alternative splicing and the influence of extracellular kinases that phosphorylate ERα on E2-induced splicing are unknown. MCF-7 and its anti-estrogen derivatives were used for the majority of the assays. CD44 mini gene was used to measure the effect of E2 and AKT on alternative splicing. ExonHit array analysis was performed to identify E2 and AKT-regulated endogenous alternatively spliced apoptosis-related genes. Quantitative reverse transcription polymerase chain reaction was performed to verify alternative splicing. ERα binding to alternatively spliced genes was verified by chromatin immunoprecipitation assay. Bromodeoxyuridine incorporation-ELISA and Annexin V labeling assays were done to measure cell proliferation and apoptosis, respectively. We identified the targets of E2-induced alternative splicing and deconstructed some of the mechanisms surrounding E2-induced splicing by combining splice array with ERα cistrome and gene expression array. E2-induced alternatively spliced genes fall into at least two subgroups: coupled to E2-regulated transcription and ERα binding to the gene without an effect on rate of transcription. Further, AKT, which phosphorylates both ERα and splicing factors, influenced ERα:E2 dependent splicing in a gene-specific manner. Genes that are alternatively spliced include FAS/CD95, FGFR2, and AXIN-1. E2 increased the expression of FGFR2 C1 isoform but reduced C3 isoform at mRNA level. E2-induced alternative splicing of FAS and FGFR2 in MCF-7 cells correlated with resistance to FAS activation-induced apoptosis and response to keratinocyte growth factor (KGF), respectively. Resistance of MCF-7 breast cancer cells to the anti-estrogen tamoxifen was associated with ER

  10. Estrogen-related receptor beta interacts with Oct4 to positively regulate Nanog gene expression

    NARCIS (Netherlands)

    D.L.C. van den Berg (Debbie); W. Zhang (Wensheng); A. Yates (Adam); M.P. Engelen (Erik); K. Takacs (Katalin); K. Bezstarosti (Karel); J.A.A. Demmers (Jeroen); I. Chambers (Ian); R.A. Poor (Raymond)

    2008-01-01

    textabstractEmbryonic stem (ES) cell self-renewal is regulated by transcription factors, including Oct4, Sox2, and Nanog. A number of additional transcriptional regulators of ES cell self-renewal have recently been identified, including the orphan nuclear receptor estrogen-related receptor beta

  11. Alterations in Circulating miRNA Levels following Early-Stage Estrogen Receptor-Positive Breast Cancer Resection in Post-Menopausal Women

    DEFF Research Database (Denmark)

    Kodahl, Annette R; Zeuthen, Pernille; Binder, Harald

    2014-01-01

    INTRODUCTION: Circulating microRNAs (miRNAs) exhibit remarkable stability and may serve as biomarkers in several clinical cancer settings. The aim of this study was to investigate changes in the levels of specific circulating miRNA following breast cancer surgery and evaluate whether these altera...... and could potentially be used to monitor whether all cancer cells have been removed at surgery and/or, subsequently, whether the patients develop recurrence.......INTRODUCTION: Circulating microRNAs (miRNAs) exhibit remarkable stability and may serve as biomarkers in several clinical cancer settings. The aim of this study was to investigate changes in the levels of specific circulating miRNA following breast cancer surgery and evaluate whether...... these alterations were also observed in an independent data set. METHODS: Global miRNA analysis was performed on prospectively collected serum samples from 24 post-menopausal women with estrogen receptor-positive early-stage breast cancer before surgery and 3 weeks after tumor resection using global LNA...

  12. IL-8 expression and its possible relationship with estrogen-receptor-negative status of breast cancer cells

    Science.gov (United States)

    Freund, Ariane; Chauveau, Corine; Brouillet, Jean-Paul; Lucas, Annick; Lacroix, Matthieu; Licznar, Anne; Vignon, Françoise; Lazennec, Gwendal

    2003-01-01

    Estrogen receptor (ER) status is an important parameter in breast cancer management as ER-positive breast cancers have a better prognosis than ER-negative tumors. This difference comes essentially from the lower aggressiveness and invasiveness of ER-positive tumors. Here, we demonstrate, that IL-8 was clearly overexpressed in most ER-negative breast, ovary cell lines and breast tumor samples tested, whereas no significant IL-8 level could be detected in ER-positive breast or ovarian cell lines. We have also cloned human IL-8 from ER-negative MDA-MB-231 cells and we show that IL-8 produced by breast cancer cells is identical to monocyte-derived IL-8. Interestingly, the invasion potential of ER-negative breast cancer cells is associated at least in part with expression of interleukin-8 (IL-8), but not with IL-8 receptors levels. Moreover, IL-8 increases the invasiveness of ER-positive breast cancer cells by 2 fold, thus confirming the invasion-promoting role of IL-8. On the other hand, exogenous expression of estrogen receptors in ER-negative cells led to a decrease of IL-8 levels. In summary, our data show that IL-8 expression is negatively linked to ER-status of breast and ovarian cancer cells. We also support the idea that IL-8 expression is associated with a higher invasiveness potential of cancer cells in vitro, which suggests that IL-8 could be a novel marker of tumor aggressiveness. PMID:12527894

  13. Assessment of cellular estrogenic activity based on estrogen receptor-mediated reduction of soluble-form catechol-O-methyltransferase (COMT expression in an ELISA-based system.

    Directory of Open Access Journals (Sweden)

    Philip Wing-Lok Ho

    Full Text Available Xenoestrogens are either natural or synthetic compounds that mimic the effects of endogenous estrogen. These compounds, such as bisphenol-A (BPA, and phthalates, are commonly found in plastic wares. Exposure to these compounds poses major risk to human health because of the potential to cause endocrine disruption. There is huge demand for a wide range of chemicals to be assessed for such potential for the sake of public health. Classical in vivo assays for endocrine disruption are comprehensive but time-consuming and require sacrifice of experimental animals. Simple preliminary in vitro screening assays can reduce the time and expense involved. We previously demonstrated that catechol-O-methyltransferase (COMT is transcriptionally regulated by estrogen via estrogen receptor (ER. Therefore, detecting corresponding changes of COMT expression in estrogen-responsive cells may be a useful method to estimate estrogenic effects of various compounds. We developed a novel cell-based ELISA to evaluate cellular response to estrogenicity by reduction of soluble-COMT expression in ER-positive MCF-7 cells exposed to estrogenic compounds. In contrast to various existing methods that only detect bioactivity, this method elucidates direct physiological effect in a living cell in response to a compound. We validated our assay using three well-characterized estrogenic plasticizers - BPA, benzyl butyl phthalate (BBP, and di-n-butyl phthalate (DBP. Cells were exposed to either these plasticizers or 17β-estradiol (E2 in estrogen-depleted medium with or without an ER-antagonist, ICI 182,780, and COMT expression assayed. Exposure to each of these plasticizers (10(-9-10(-7M dose-dependently reduced COMT expression (p<0.05, which was blocked by ICI 182,780. Reduction of COMT expression was readily detectable in cells exposed to picomolar level of E2, comparable to other in vitro assays of similar sensitivity. To satisfy the demand for in vitro assays targeting different

  14. Expression of the G protein-coupled estrogen receptor (GPER in endometriosis: a tissue microarray study

    Directory of Open Access Journals (Sweden)

    Samartzis Nicolas

    2012-04-01

    Full Text Available Abstract Background The G protein-coupled estrogen receptor (GPER is thought to be involved in non-genomic estrogen responses as well as processes such as cell proliferation and migration. In this study, we analyzed GPER expression patterns from endometriosis samples and normal endometrial tissue samples and compared these expression profiles to those of the classical sex hormone receptors. Methods A tissue microarray, which included 74 samples from different types of endometriosis (27 ovarian, 19 peritoneal and 28 deep-infiltrating and 30 samples from normal endometrial tissue, was used to compare the expression levels of the GPER, estrogen receptor (ER-alpha, ER-beta and progesterone receptor (PR. The immunoreactive score (IRS was calculated separately for epithelium and stroma as the product of the staining intensity and the percentage of positive cells. The expression levels of the hormonal receptors were dichotomized into low (IRS  =6 expression groups. Results The mean epithelial IRS (+/−standard deviation, range of cytoplasmic GPER expression was 1.2 (+/−1.7, 0–4 in normal endometrium and 5.1 (+/−3.5, 0–12 in endometriosis (p p = 0.71, of ER-alpha 10.6 (+/−2.4, 3–12 and 9.8 (+/−3.0, 2–12; p = 0.26, of ER-beta 2.4 (+/−2.2; 0–8 and 5.6 (+/−2.6; 0–10; p p p p = 0.001, of ER-beta 1.8 (+/−2.0; 0–8 and 5.4 (+/−2.5; 0–10; p p���= 0.044, respectively. Cytoplasmic GPER expression was not detectable in the stroma of endometrium and endometriosis. The observed frequency of high epithelial cytoplasmic GPER expression levels was 50% (n = 30/60 in the endometriosis and none (0/30 in the normal endometrium samples (p p = 0.01, as compared to peritoneal (9/18, 50% or deep-infiltrating endometriotic lesions (7/22, 31.8%. The frequency of high stromal nuclear GPER expression levels was 100% (n = 74/74 in endometriosis and 76.7% (n = 23/30 in normal endometrium (p

  15. Estrogen receptor alpha polymorphisms and the risk of prostate cancer development.

    Science.gov (United States)

    Jurečeková, Jana; Babušíková, Eva; Kmeťová, Monika; Kliment, Ján; Dobrota, Dušan

    2015-11-01

    The main purpose of the study was to evaluate the effect of two polymorphisms in the estrogen receptor alpha, rs2077647 and rs3798577, on the development of prostate cancer, their correlation with selected clinical characteristics, as well as consideration of potential interactions between four estrogen receptor alpha polymorphisms (rs2077647, rs3798577, PvuII, XbaI). The study was performed using 395 patients with histologically verified prostate cancer and 253 healthy male controls. The CC genotype of rs2077647 was significantly associated with prostate cancer (OR = 1.61). No association was found between rs3798577 polymorphism and prostate cancer. After stratification of patients according to the age at diagnosis and Gleason score, we observed significant correlation between rs2077647 polymorphism and prostate cancer risk in patients diagnosed before the age of 60 as well as patients with Gleason score prostate cancer risk development in patients older than 60 and with Gleason score ≥7. Double analysis of each combination of four studied polymorphisms showed that presence of at least three variant alleles was associated with prostate cancer risk in all combinations, while each containing rs3798577 was significantly associated with development of high-grade carcinomas. The present study suggests that rs2077647 polymorphism may be a risk factor for prostate cancer especially in patients diagnosed before the age of 60, while rs3798577 polymorphism could probably serve rather as promoting factor in combination with other polymorphisms in estrogen receptor alpha contributing preferably to development of high-grade carcinomas.

  16. The Estrogen Receptor and Its Variants as Risk Factors in Breast Cancer

    National Research Council Canada - National Science Library

    Murph, Leigh

    2001-01-01

    The overall goal of this research is to understand how the estrogen receptor (ER) signal transduction pathway is altered during breast tumorigenesis and if altered ER signal transduction increases the risk of developing breast cancer...

  17. Inhibition of estrogen-responsive gene activation by the retinoid X receptor beta: evidence for multiple inhibitory pathways.

    Science.gov (United States)

    Segars, J H; Marks, M S; Hirschfeld, S; Driggers, P H; Martinez, E; Grippo, J F; Brown, M; Wahli, W; Ozato, K

    1993-04-01

    The retinoid X receptor beta (RXR beta; H-2RIIBP) forms heterodimers with various nuclear hormone receptors and binds multiple hormone response elements, including the estrogen response element (ERE). In this report, we show that endogenous RXR beta contributes to ERE binding activity in nuclear extracts of the human breast cancer cell line MCF-7. To define a possible regulatory role of RXR beta regarding estrogen-responsive transcription in breast cancer cells, RXR beta and a reporter gene driven by the vitellogenin A2 ERE were transfected into estrogen-treated MCF-7 cells. RXR beta inhibited ERE-driven reporter activity in a dose-dependent and element-specific fashion. This inhibition occurred in the absence of the RXR ligand 9-cis retinoic acid. The RXR beta-induced inhibition was specific for estrogen receptor (ER)-mediated ERE activation because inhibition was observed in ER-negative MDA-MB-231 cells only following transfection of the estrogen-activated ER. No inhibition of the basal reporter activity was observed. The inhibition was not caused by simple competition of RXR beta with the ER for ERE binding, since deletion mutants retaining DNA binding activity but lacking the N-terminal or C-terminal domain failed to inhibit reporter activity. In addition, cross-linking studies indicated the presence of an auxiliary nuclear factor present in MCF-7 cells that contributed to RXR beta binding of the ERE. Studies using known heterodimerization partners of RXR beta confirmed that RXR beta/triiodothyronine receptor alpha heterodimers avidly bind the ERE but revealed the existence of another triiodothyronine-independent pathway of ERE inhibition. These results indicate that estrogen-responsive genes may be negatively regulated by RXR beta through two distinct pathways.

  18. The role of estrogen in bipolar disorder, a review

    DEFF Research Database (Denmark)

    Meinhard, Ninja; Kessing, Lars Vedel; Vinberg, Maj

    2014-01-01

    hormones, e.g. estrogen, are fluctuating and particularly postpartum there is a steep fall in the levels of serum estrogen. The role of estrogen in women with bipolar disorder is, however, not fully understood. Aim: The main objective of this review is to evaluate the possible relation between serum...... estrogen levels and women with bipolar disorder including studies of the anti manic effects of the selective estrogen receptor modulator tamoxifen. Method: A systematically literature search on PubMed was conducted: two studies regarding the connection between serum estrogen levels and women with bipolar...... tamoxifen studies found that tamoxifen was effective in producing antimanic effects. Conclusion: These results indicate that estrogen fluctuations may be an important factor in the etiology of bipolar disorder and it is obvious that more research on this topic is needed to clarify the role of estrogen...

  19. The role of estrogen in bipolar disorder, a review

    DEFF Research Database (Denmark)

    Meinhard, Ninja; Kessing, Lars Vedel; Vinberg, Maj

    2014-01-01

    hormones, e.g. estrogen, are fluctuating and particularly postpartum there is a steep fall in the levels of serum estrogen. The role of estrogen in women with bipolar disorder is, however, not fully understood. AIM: The main objective of this review is to evaluate the possible relation between serum...... estrogen levels and women with bipolar disorder including studies of the anti manic effects of the selective estrogen receptor modulator tamoxifen. METHOD: A systematically literature search on PubMed was conducted: two studies regarding the connection between serum estrogen levels and women with bipolar...... tamoxifen studies found that tamoxifen was effective in producing antimanic effects. CONCLUSION: These results indicate that estrogen fluctuations may be an important factor in the etiology of bipolar disorder and it is obvious that more research on this topic is needed to clarify the role of estrogen...

  20. Prenylated isoflavonoids from plants as selective estrogen receptor modulators (phytoSERMs)

    NARCIS (Netherlands)

    Simons, R.; Gruppen, H.; Bovee, T.F.H.; Verbruggen, M.A.; Vincken, J.P.

    2012-01-01

    Isoflavonoids are a class of secondary metabolites, which comprise amongst others the subclasses of isoflavones, isoflavans, pterocarpans and coumestans. Isoflavonoids are abundant in Leguminosae, and many of them can bind to the human estrogen receptor (hER) with affinities similar to or lower than

  1. In vivo imaging of brain estrogen receptors in rats : a 16α-18F-fluoro-17β-estradiol PET study

    NARCIS (Netherlands)

    Khayum, Mohammed A; de Vries, Erik F J; Glaudemans, Andor W J M; Dierckx, Rudi A J O; Doorduin, Janine

    UNLABELLED: The steroid hormone estrogen is important for brain functioning and is thought to be involved in brain diseases, such as Alzheimer disease and depression. The action of estrogen is mediated by estrogen receptors (ERs). To understand the role of estrogens in brain functioning, it is

  2. Estrogen, Angiogenesis, Immunity and Cell Metabolism: Solving the Puzzle.

    Science.gov (United States)

    Trenti, Annalisa; Tedesco, Serena; Boscaro, Carlotta; Trevisi, Lucia; Bolego, Chiara; Cignarella, Andrea

    2018-03-15

    Estrogen plays an important role in the regulation of cardiovascular physiology and the immune system by inducing direct effects on multiple cell types including immune and vascular cells. Sex steroid hormones are implicated in cardiovascular protection, including endothelial healing in case of arterial injury and collateral vessel formation in ischemic tissue. Estrogen can exert potent modulation effects at all levels of the innate and adaptive immune systems. Their action is mediated by interaction with classical estrogen receptors (ERs), ERα and ERβ, as well as the more recently identified G-protein coupled receptor 30/G-protein estrogen receptor 1 (GPER1), via both genomic and non-genomic mechanisms. Emerging data from the literature suggest that estrogen deficiency in menopause is associated with an increased potential for an unresolved inflammatory status. In this review, we provide an overview through the puzzle pieces of how 17β-estradiol can influence the cardiovascular and immune systems.

  3. Iodine stimulates estrogen receptor singling and its systemic level is increased in surgical patients due to topical absorption.

    Science.gov (United States)

    He, Shaohua; Wang, Bingchan; Lu, Xiyi; Miao, Suyu; Yang, Fengming; Zava, Theodore; Ding, Qiang; Zhang, Shijiang; Liu, Jiayin; Zava, David; Shi, Yuenian Eric

    2018-01-02

    Iodine is crucial for thyroid hormone production. However, recent epidemiologic studies have shown that breast cancer patients have an elevated risk of developing thyroid cancer and vice versa. A notable finding in this study is that iodine stimulated the transcriptional activity of estrogen receptor-α (ER-α) in breast cancer cells. Iodine stimulated expression of several ER-α regulated gene including PS2 , Cathepsin D , CyclinD1 , and PR both in vitro and in nude mice, which is consistent with its stimulation of both anchorage-dependent and -independent growth of ER-α positive breast cancer cells and the effect to dampen tumor shrinkage of MCF-7 xenograft in ovariectomized nude mice. Analyses of clinical urine samples from breast cancer patients undergoing surgery demonstrated that urinary iodine levels were significantly higher than that in controls; and this increased level is due to the antiseptic use of iodine during breast surgery. The present study indicates that excess iodine intake may be an unfavorable factor in breast cancer by stimulation of ER-α transcriptional activity.

  4. A transcriptionally active estrogen receptor mutant is a novel type of dominant negative inhibitor of estrogen action.

    Science.gov (United States)

    McInerney, E M; Ince, B A; Shapiro, D J; Katzenellenbogen, B S

    1996-12-01

    We have characterized a human estrogen receptor (ER) mutant, V364E, which has a single amino acid substitution in its hormone-binding domain. This ER mutant is fully active or even superactive at saturating levels of estradiol (10(-8) M E2) yet has the capacity to act as a strong dominant negative inhibitor of the wild type ER. In transient transfection assays using ER-negative Chinese hamster ovary (CHO) cells and two different estrogen response element (ERE)-containing promoter reporter genes, V364E treated with 10(-8) M E2 exhibited approximately 250% and 100% of the activity of the wild type ER with these two promoter contexts, respectively. Despite the high activity of V364E when present alone in cells, coexpression of both V364E and wild type ER causes a significant decrease in overall ER-mediated transcriptional activity. On the TATA promoter, where V364E was more inhibitory, estrogen-stimulated activity was reduced by approximately 50% at a 1:1 ratio of mutant to wild type ER expression vector, and at a 10:1 ratio, 75% of ER activity was inhibited. V364E was expressed at lower levels than wild type ER and has a approximately 40-fold lower affinity for E2 compared with wild type ER. In promoter interference assays, V364E exhibited a strict dependence upon E2 for binding to an ERE. Surprisingly, even when V364E was unable to bind to ERE DNA (i.e. either at low E2 concentration or by mutation of its DNA-binding domain), this mutant retained full dominant negative activity. This highly active ER mutant is, thus, able to repress ER-mediated transcription when the mutant and wild type ER are present together in cells, even without DNA binding. Since competition for ERE binding and the formation of inactive heterodimers cannot fully account for the dominant negative activity of V364E, it is probable that altered interactions with proteins important in ER-mediated transcription play a key role in the repression of transcription by V364E. The properties and probable

  5. Preliminary genetic imaging study of the association between estrogen receptor-α gene polymorphisms and harsh human maternal parenting.

    Science.gov (United States)

    Lahey, Benjamin B; Michalska, Kalina J; Liu, Chunyu; Chen, Qi; Hipwell, Alison E; Chronis-Tuscano, Andrea; Waldman, Irwin D; Decety, Jean

    2012-09-06

    A failure of neural changes initiated by the estrogen surge in late pregnancy to reverse the valence of infant stimuli from aversive to rewarding is associated with dysfunctional maternal behavior in nonhuman mammals. Estrogen receptor-α plays the crucial role in mediating these neural effects of estrogen priming. This preliminary study examines associations between estrogen receptor-α gene polymorphisms and human maternal behavior. Two polymorphisms were associated with human negative maternal parenting. Furthermore, hemodynamic responses in functional magnetic resonance imaging to child stimuli in neural regions associated with social cognition fully mediated the association between genetic variation and negative parenting. This suggests testable hypotheses regarding a biological pathway between genetic variants and dysfunctional human maternal parenting. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. The selective estrogen receptor modulator raloxifene inhibits neutrophil extracellular trap formation.

    Directory of Open Access Journals (Sweden)

    Roxana Flores

    2016-12-01

    Full Text Available Raloxifene is a selective estrogen receptor modulator typically prescribed for the prevention/treatment of osteoporosis in postmenopausal women. Although raloxifene is known to have anti-inflammatory properties, its effect on human neutrophils, the primary phagocytic leukocytes of the immune system, remain poorly understood. Here, through a screen of pharmacologically active small molecules, we find that raloxifene prevents neutrophil cell death in response to the classical activator phorbol 12-myristate 13-acetate (PMA, a compound known to induce formation of DNA-based neutrophil extracellular traps (NETs. Inhibition of PMA-induced NET production by raloxifene was confirmed using quantitative and imaging-based assays. Human neutrophils from both male and female donors express the nuclear estrogen receptors ERα and ERβ, known targets of raloxifene. Like raloxifene, selective antagonists of these receptors inhibit PMA-induced NET production. Furthermore, raloxifene inhibited PMA-induced ERK phosphorylation but not reactive oxygen species (ROS production, pathways known to be key modulators of NET production. Finally, we found that raloxifene inhibited PMA-induced, NET-based killing of the leading human bacterial pathogen, methicillin-resistant Staphylococcus aureus (MRSA. Our results reveal that raloxifene is a potent modulator of neutrophil function and NET production.

  7. Immunohistochemical detection of estrogen receptors in canine mammary tumors

    Directory of Open Access Journals (Sweden)

    Elena Atanaskova Petrov

    2016-03-01

    Full Text Available Mammary tumors are among the most common neoplasms in intact female dogs.They have a complex morphology, usually affecting middle age and older bitches. Almost 50% of the mammary tumors in dogs are malignant neoplasms. Prognosis is based on several factors: stage, age, tumor size, metastasis, histopathology, ovariectomy status and hormone-receptor activity. Immunohistochemical (IHC measurement has become increasingly an important diagnostic and prognostic parameter, with the development of monoclonal antibodies against nuclear estrogen and progestin receptors. The aim of this study was to detect the presence of ER receptors in malignant canine mammary tumors and to identify their association with the clinical course of the tumor. Mammary tumor samples have been obtained by mastectomy from dogs presented at our clinic. Detailed clinical examination, CBC and basic serum biochemical profile were performed in all patients. Surgery was the only treatment. Histopathological examination and immunohistochemical detection of estrogen α receptors (ERα was performed on 8 formalin-fixed, paraffin-embedded tissue samples, using the PT LINK immunoperoxidase technique. Histopathological examination of the mammary tumor samples (n=11 revealed tubular adenocarcinoma (n=6,54.5% and ductal adenocarcinoma (n=3, 27.3%, one patient with benign adenoma and one with mastitis. Patients with positive ER tumors are alive, without remission, while 3 of the patients that were ER negative died due to lung metastases. According to our results, it can be concluded that the appearance and development of canine mammary tumors is highly connected with ovarian steroid hormones and that immunostaining of the tumors may be used as a good prognostic parameter in these patients.

  8. Estrogen Receptor Binding Affinity of Food Contact Material Components Estimated by QSAR.

    Science.gov (United States)

    Sosnovcová, Jitka; Rucki, Marián; Bendová, Hana

    2016-09-01

    The presented work characterized components of food contact materials (FCM) with potential to bind to estrogen receptor (ER) and cause adverse effects in the human organism. The QSAR Toolbox, software application designed to identify and fill toxicological data gaps for chemical hazard assessment, was used. Estrogen receptors are much less of a lock-and-key interaction than highly specific ones. The ER is nonspecific enough to permit binding with a diverse array of chemical structures. There are three primary ER binding subpockets, each with different requirements for hydrogen bonding. More than 900 compounds approved as of FCM components were evaluated for their potential to bind on ER. All evaluated chemicals were subcategorized to five groups with respect to the binding potential to ER: very strong, strong, moderate, weak binder, and no binder to ER. In total 46 compounds were characterized as potential disturbers of estrogen receptor. Among the group of selected chemicals, compounds with high and even very high affinity to the ER binding subpockets were found. These compounds may act as gene activators and cause adverse effects in the organism, particularly during pregnancy and breast-feeding. It should be considered to carry out further in vitro or in vivo tests to confirm their potential to disturb the regulation of physiological processes in humans by abnormal ER signaling and subsequently remove these chemicals from the list of approved food contact materials. Copyright© by the National Institute of Public Health, Prague 2016

  9. A Role for Estrogen Receptor Phosphorylation in the Resistance to Tamoxifen

    International Nuclear Information System (INIS)

    De Leeuw, R.; Neefjes, J.; Michalides, R.

    2011-01-01

    About two thirds of all human breast cancer cases are estrogen receptor positive. The drug of first choice for these patients is tamoxifen. However, about half of the recurrences after removal of the primary tumor are or become resistant to this drug. While many mechanisms have been identified for tamoxifen resistance in the lab, at present only a few have been translated to the clinic. This paper highlights the role in tamoxifen resistance of phosphorylation by different kinases on different sites of the estrogen receptor. We will discuss the molecular pathways and kinases that are involved in phosphorylation of ERa and how these affect tamoxifen resistance. Finally, we will elaborate on the clinical translation of these observations and the possibility to predict tamoxifen responses in patient tumor samples before treatment onset. The findings made originally on the bench may translate into a better and personalized treatment of breast cancer patients using an old and safe anticancer drug: tamoxifen

  10. Estrogen receptor alpha and risk for cognitive impairment in postmenopausal women

    DEFF Research Database (Denmark)

    Olsen, Line; Rasmussen, Henrik B; Hansen, Thomas

    2006-01-01

    The estrogen receptor alpha (ESR1) gene has been implicated in the process of cognitive impairment in elderly women. In a paired case-control study, we tested whether two ESR1 gene polymorphisms (the XbaI and PvuII sites) are risk factors for cognitive impairment as measured by the six-item Orien......The estrogen receptor alpha (ESR1) gene has been implicated in the process of cognitive impairment in elderly women. In a paired case-control study, we tested whether two ESR1 gene polymorphisms (the XbaI and PvuII sites) are risk factors for cognitive impairment as measured by the six......-item Orientation-Memory-Concentration test in postmenopausal Danish women. Hormone replacement therapy, age and executive cognitive ability were examined as covariates for ESR1 gene effects on cognitive impairment. The XbaI polymorphism showed a marginal effect on cognitive abilities (P=0.054) when adjusted...... cognitive ability. These data support that the ESR1 gene variants affect cognitive functioning in postmenopausal women....

  11. DEHP exposure impairs mouse oocyte cyst breakdown and primordial follicle assembly through estrogen receptor-dependent and independent mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Mu, Xinyi [Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing 400016 (China); Department of Histology and Embryology, College of Basic Medicine, Chongqing Medical University, Chongqing 400016 (China); Liao, Xinggui; Chen, Xuemei; Li, Yanli; Wang, Meirong; Shen, Cha; Zhang, Xue; Wang, Yingxiong; Liu, Xueqing [Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing 400016 (China); He, Junlin, E-mail: hejunlin_11@aliyun.com [Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing 400016 (China)

    2015-11-15

    Highlights: • DEHP inhibits primordial folliculogenesis in vivo and in vitro. • Estrogen receptors participate in the effect of DEHP on early ovarian development. • DEHP exposure impairs the expression of Notch2 signaling components. • DEHP exposure disrupts the proliferation of pregranulosa precursor cells. - Abstract: Estrogen plays an essential role in the development of mammalian oocytes, and recent studies suggest that it also regulates primordial follicle assembly in the neonatal ovaries. During the last decade, potential exposure of humans and animals to estrogen-like endocrine disrupting chemicals has become a growing concern. In the present study, we focused on the effect of diethylhexyl phthalate (DEHP), a widespread plasticizer with estrogen-like activity, on germ-cell cyst breakdown and primordial follicle assembly in the early ovarian development of mouse. Neonatal mice injected with DEHP displayed impaired cyst breakdown. Using ovary organ cultures, we revealed that impairment was mediated through estrogen receptors (ERs), as ICI 182,780, an efficient antagonist of ER, reversed this DEHP-mediated effect. DEHP exposure reduced the expression of ERβ, progesterone receptor (PR), and Notch2 signaling components. Finally, DEHP reduced proliferation of pregranulosa precursor cells during the process of primordial folliculogenesis. Together, our results indicate that DEHP influences oocyte cyst breakdown and primordial follicle formation through several mechanisms. Therefore, exposure to estrogen-like chemicals during fetal or neonatal development may adversely influence early ovarian development.

  12. Estrogen is essential but not sufficient to induce endometriosis

    Indian Academy of Sciences (India)

    Mosami Galvankar

    2017-05-11

    May 11, 2017 ... Beyond estrogen, the levels of Estrogen Receptors (ER) are also altered in the ..... lesions were found on the bladder on day 7 and the lesions ..... effects of adipose tissue on cancer development and progression. Endocr. Rev ...

  13. A new series of estrogen receptor modulators that display selectivity for estrogen receptor beta.

    Science.gov (United States)

    Henke, Brad R; Consler, Thomas G; Go, Ning; Hale, Ron L; Hohman, Dana R; Jones, Stacey A; Lu, Amy T; Moore, Linda B; Moore, John T; Orband-Miller, Lisa A; Robinett, R Graham; Shearin, Jean; Spearing, Paul K; Stewart, Eugene L; Turnbull, Philip S; Weaver, Susan L; Williams, Shawn P; Wisely, G Bruce; Lambert, Millard H

    2002-12-05

    A series of 1,3,5-triazine-based estrogen receptor (ER) modulators that are modestly selective for the ERbeta subtype are reported. Compound 1, which displayed modest potency and selectivity for ERbeta vs ERalpha, was identified via high-throughput screening utilizing an ERbeta SPA-based binding assay. Subsequent analogue preparation resulted in the identification of compounds such as 21 and 43 that display 25- to 30-fold selectivity for ERbeta with potencies in the 10-30 nM range. These compounds profile as full antagonists at ERbeta and weak partial agonists at ERalpha in a cell-based reporter gene assay. In addition, the X-ray crystal structure of compound 15 complexed with the ligand binding domain of ERbeta has been solved and was utilized in the design of more conformationally restrained analogues such as 31 in an attempt to increase selectivity for the ERbeta subtype.

  14. Inhibition of estrogen-responsive gene activation by the retinoid X receptor beta: evidence for multiple inhibitory pathways.

    OpenAIRE

    Segars, J H; Marks, M S; Hirschfeld, S; Driggers, P H; Martinez, E; Grippo, J F; Brown, M; Wahli, W; Ozato, K

    1993-01-01

    The retinoid X receptor beta (RXR beta; H-2RIIBP) forms heterodimers with various nuclear hormone receptors and binds multiple hormone response elements, including the estrogen response element (ERE). In this report, we show that endogenous RXR beta contributes to ERE binding activity in nuclear extracts of the human breast cancer cell line MCF-7. To define a possible regulatory role of RXR beta regarding estrogen-responsive transcription in breast cancer cells, RXR beta and a reporter gene d...

  15. Enhanced expression of G-protein coupled estrogen receptor (GPER/GPR30) in lung cancer

    International Nuclear Information System (INIS)

    Jala, Venkatakrishna Rao; Radde, Brandie N; Haribabu, Bodduluri; Klinge, Carolyn M

    2012-01-01

    G-protein-coupled estrogen receptor (GPER/GPR30) was reported to bind 17β-estradiol (E 2 ), tamoxifen, and ICI 182,780 (fulvestrant) and promotes activation of epidermal growth factor receptor (EGFR)-mediated signaling in breast, endometrial and thyroid cancer cells. Although lung adenocarcinomas express estrogen receptors α and β (ERα and ERβ), the expression of GPER in lung cancer has not been investigated. The purpose of this study was to examine the expression of GPER in lung cancer. The expression patterns of GPER in various lung cancer lines and lung tumors were investigated using standard quantitative real time PCR (at mRNA levels), Western blot and immunohistochemistry (IHC) methods (at protein levels). The expression of GPER was scored and the pairwise comparisons (cancer vs adjacent tissues as well as cancer vs normal lung tissues) were performed. Analysis by real-time PCR and Western blotting revealed a significantly higher expression of GPER at both mRNA and protein levels in human non small cell lung cancer cell (NSCLC) lines relative to immortalized normal lung bronchial epithelial cells (HBECs). The virally immortalized human small airway epithelial cell line HPL1D showed higher expression than HBECs and similar expression to NSCLC cells. Immunohistochemical analysis of tissue sections of murine lung adenomas as well as human lung adenocarcinomas, squamous cell carcinomas and non-small cell lung carcinomas showed consistently higher expression of GPER in the tumor relative to the surrounding non-tumor tissue. The results from this study demonstrate increased GPER expression in lung cancer cells and tumors compared to normal lung. Further evaluation of the function and regulation of GPER will be necessary to determine if GPER is a marker of lung cancer progression

  16. Estrogen receptor α and aryl hydrocarbon receptor cross-talk in a transfected hepatoma cell line (HepG2 exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

    Directory of Open Access Journals (Sweden)

    Manuela Göttel

    2014-01-01

    Full Text Available The prototype dioxin congener 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD is known to exert anti-estrogenic effects via activation of the aryl hydrocarbon receptor (AhR by interfering with the regulation of oestrogen homeostasis and the estrogen receptor α (ERα signalling pathway. The AhR/ER cross-talk is considered to play a crucial role in TCDD- and E2-dependent mechanisms of carcinogenesis, though the concerted mechanism of action in the liver is not yet elucidated. The present study investigated TCDD's impact on the transcriptional cross-talk between AhR and ERα and its modulation by 17β-estradiol (E2 in the human hepatoma cell line HepG2, which is AhR-responsive but ERα-negative. Transient transfection assays with co-transfection of hERα and supplementation of receptor antagonists showed anti-estrogenic action of TCDD via down-regulation of E2-induced ERα signaling. In contrast, enhancement of AhR signaling dependent on ERα was observed providing evidence for increased cytochrome P450 (CYP induction to promote E2 metabolism. However, relative mRNA levels of major E2-metabolizing CYP1A1 and 1B1 and the main E2-detoxifying catechol-O-methyltransferase were not affected by the co-treatments. This study provides new evidence of a TCDD-activated AhR-mediated molecular AhR/ERα cross-talk mechanism at transcriptional level via indirect inhibition of ERα and enhanced transcriptional activity of AhR in HepG2 cells.

  17. Labeled estrogens as mammary tumor probes

    International Nuclear Information System (INIS)

    Feenstra, A.

    1981-01-01

    In this thesis estrogens labeled with a gamma or positron emitting nuclide, called estrogen-receptor binding radiopharmaceuticals are investigated as mammary tumour probes. The requirements for estrogen-receptor binding radiopharmaceuticals are formulated and the literature on estrogens labeled for this purpose is reviewed. The potential of mercury-197/197m and of carbon-11 as label for estrogen-receptor binding radiopharmaceuticals is investigated. The synthesis of 197 Hg-labeled 4-mercury-estradiol and 2-mercury-estradiol and their properties in vitro and in vivo are described. It appears that though basically carbon-11 labeled compounds are very promising as mammary tumour probes, their achievable specific activity has to be increased. (Auth.)

  18. Estrogens regulate neuroinflammatory genes via estrogen receptors α and β in the frontal cortex of middle-aged female rats

    Directory of Open Access Journals (Sweden)

    Mahó Sándor

    2011-07-01

    Full Text Available Abstract Background Estrogens exert anti-inflammatory and neuroprotective effects in the brain mainly via estrogen receptors α (ERα and β (ERβ. These receptors are members of the nuclear receptor superfamily of ligand-dependent transcription factors. This study was aimed at the elucidation of the effects of ERα and ERβ agonists on the expression of neuroinflammatory genes in the frontal cortex of aging female rats. Methods To identify estrogen-responsive immunity/inflammation genes, we treated middle-aged, ovariectomized rats with 17β-estradiol (E2, ERα agonist 16α-lactone-estradiol (16α-LE2 and ERβ agonist diarylpropionitrile (DPN, or vehicle by Alzet minipump delivery for 29 days. Then we compared the transcriptomes of the frontal cortex of estrogen-deprived versus ER agonist-treated animals using Affymetrix Rat230 2.0 expression arrays and TaqMan-based quantitative real-time PCR. Microarray and PCR data were evaluated by using Bioconductor packages and the RealTime StatMiner software, respectively. Results Microarray analysis revealed the transcriptional regulation of 21 immunity/inflammation genes by 16α-LE2. The subsequent comparative real-time PCR study analyzed the isotype specific effects of ER agonists on neuroinflammatory genes of primarily glial origin. E2 regulated the expression of sixteen genes, including down-regulation of complement C3 and C4b, Ccl2, Tgfb1, macrophage expressed gene Mpeg1, RT1-Aw2, Cx3cr1, Fcgr2b, Cd11b, Tlr4 and Tlr9, and up-regulation of defensin Np4 and RatNP-3b, IgG-2a, Il6 and ER gene Esr1. Similar to E2, both 16α-LE2 and DPN evoked up-regulation of defensins, IgG-2a and Il6, and down-regulation of C3 and its receptor Cd11b, Ccl2, RT1-Aw2 and Fcgr2b. Conclusions These findings provide evidence that E2, 16α-LE2 and DPN modulate the expression of neuroinflammatory genes in the frontal cortex of middle-aged female rats via both ERα and ERβ. We propose that ERβ is a promising target to suppress

  19. Estrogenic and anti-estrogenic influences in cultured brown trout hepatocytes: Focus on the expression of some estrogen and peroxisomal related genes and linked phenotypic anchors.

    Science.gov (United States)

    Madureira, Tânia Vieira; Malhão, Fernanda; Pinheiro, Ivone; Lopes, Célia; Ferreira, Nádia; Urbatzka, Ralph; Castro, L Filipe C; Rocha, Eduardo

    2015-12-01

    Estrogens, estrogenic mimics and anti-estrogenic compounds are known to target estrogen receptors (ER) that can modulate other nuclear receptor signaling pathways, such as those controlled by the peroxisome proliferator-activated receptor (PPAR), and alter organelle (inc. peroxisome) morphodynamics. By using primary isolated brown trout (Salmo trutta f. fario) hepatocytes after 72 and 96h of exposure we evaluated some effects in selected molecular targets and in peroxisomal morphological features caused by: (1) an ER agonist (ethinylestradiol-EE2) at 1, 10 and 50μM; (2) an ER antagonist (ICI 182,780) at 10 and 50μM; and (3) mixtures of both (Mix I-10μM EE2 and 50μM ICI; Mix II-1μM EE2 and 10μM ICI and Mix III-1μM EE2 and 50μM ICI). The mRNA levels of the estrogenic targets (ERα, ERβ-1 and vitellogenin A-VtgA) and the peroxisome structure/function related genes (catalase, urate oxidase-Uox, 17β-hydroxysteroid dehydrogenase 4-17β-HSD4, peroxin 11α-Pex11α and PPARα) were analyzed by real-time polymerase chain reaction (RT-PCR). Stereology combined with catalase immunofluorescence revealed a significant reduction in peroxisome volume densities at 50μM of EE2 exposure. Concomitantly, at the same concentration, electron microscopy showed smaller peroxisome profiles, exacerbated proliferation of rough endoplasmic reticulum, and a generalized cytoplasmic vacuolization of hepatocytes. Catalase and Uox mRNA levels decreased in all estrogenic stimuli conditions. VtgA and ERα mRNA increased after all EE2 treatments, while ERβ-1 had an inverse pattern. The EE2 action was reversed by ICI 182,780 in a concentration-dependent manner, for VtgA, ERα and Uox. Overall, our data show the great value of primary brown trout hepatocytes to study the effects of estrogenic/anti-estrogenic inputs in peroxisome kinetics and in ER and PPARα signaling, backing the still open hypothesis of crosstalk interactions between these pathways and calling for more mechanistic

  20. Differential regulation of the human progesterone receptor gene through an estrogen response element half site and Sp1 sites.

    Science.gov (United States)

    Petz, Larry N; Ziegler, Yvonne S; Schultz, Jennifer R; Kim, Hwajin; Kemper, J Kim; Nardulli, Ann M

    2004-02-01

    The progesterone receptor (PR) gene is regulated by estrogen in normal reproductive tissues and in MCF-7 human breast cancer cells. Although it is generally thought that estrogen responsiveness is mediated by interaction of the ligand-occupied estrogen receptor (ER) with estrogen response elements (EREs) in target genes, the human progesterone receptor (PR) gene lacks a palindromic ERE. Promoter A of the PR gene does, however, contain an ERE half site upstream of two adjacent Sp1 sites from +571 to +595, the +571 ERE/Sp1 site. We have examined the individual contributions of the ERE half site and the two Sp1 sites in regulating estrogen responsiveness. Transient transfection assays demonstrated that both Sp1 sites were critical for estrogen-mediated activation of the PR gene. Interestingly, rather than decreasing transcription, mutations in the ERE half site increased transcription substantially suggesting that this site plays a role in limiting transcription. Chromatin immunoprecipitation assays demonstrated that Sp1 was associated with the +571 ERE/Sp1 site in the endogenous PR gene in the absence and in the presence of estrogen, but that ERalpha was only associated with this region of the PR gene after MCF-7 cells had been treated with estrogen. Our studies provide evidence that effective regulation of transcription through the +571 ERE/Sp1 site requires the binding of ERalpha and Sp1 to their respective cis elements and the appropriate interaction of ERalpha and Sp1 with other coregulatory proteins and transcription factors.

  1. Estrogen receptor-dependent effects of bisphenol a

    Directory of Open Access Journals (Sweden)

    P. Bulzomi

    2011-01-01

    Full Text Available Bisphenol A (BPA, commonly used as building block of polycarbonate plastics, significantly affects human and animal health interfering with the action of natural hormones. Within BPA disrupting effects, a mitogenic activity and, consequently, an increased incidence of neoplastic transformations has been reported in exposed organisms. Among the several mechanisms proposed for the mitogenic BPA effects, its ability to bind to estrogen receptors (ERα and ERβ deserves particular attention. Aim of this work is to investigate ERα- and ERβ-dependent mechanisms underlying BPA proliferative effect. Binding assay confirms that BPA binds to both ERs. Cell vitality assay and Western blot analysis of protein involved in cell proliferation demonstrate that BPA acts as a double side disruptor of estrogenic effects. In fact in the presence of ERα, BPA mimics E2, increasing cell proliferation. On the contrary, in the presence of ERβ, BPA acts as an E2 antagonist preventing the hormone-induced cancer cells apoptosis. These two divergent aspects could act synergistically in the exposed organisms leading to the disruption of the balance between proliferation and apoptosis typical of E2 effects.

  2. Histone H2A.Z is essential for estrogen receptor signaling

    Science.gov (United States)

    Gévry, Nicolas; Hardy, Sara; Jacques, Pierre-Étienne; Laflamme, Liette; Svotelis, Amy; Robert, François; Gaudreau, Luc

    2009-01-01

    Incorporation of H2A.Z into the chromatin of inactive promoters has been shown to poise genes for their expression. Here we provide strong evidence that H2A.Z is incorporated into the promoter regions of estrogen receptor (ERα) target genes only upon gene induction, and that, in a cyclic pattern. Moreover, members of the human H2A.Z-depositing complex, p400, also follow the same gene recruitment kinetics as H2A.Z. Importantly, cellular depletion of H2A.Z or p400 leads to a severe defect in estrogen signaling, including loss of estrogen-specific cell proliferation. We find that incorporation of H2A.Z within TFF1 promoter chromatin allows nucleosomes to adopt preferential positions along the DNA translational axis. Finally, we provide evidence that H2A.Z is essential to allow estrogen-responsive enhancer function. Taken together, our results provide strong mechanistic insight into how H2A.Z regulates ERα-mediated gene expression and provide a novel link between H2A.Z–p400 and ERα-dependent gene regulation and enhancer function. PMID:19515975

  3. Expansion of Sphingosine Kinase and Sphingosine-1-Phosphate Receptor Function in Normal and Cancer Cells: From Membrane Restructuring to Mediation of Estrogen Signaling and Stem Cell Programming

    Science.gov (United States)

    2018-01-01

    Sphingolipids, sphingolipid metabolizing enzymes, and their receptors network are being recognized as part of the signaling mechanisms, which govern breast cancer cell growth, migration, and survival during chemotherapy treatment. Approximately 70% of breast cancers are estrogen receptor (ER) positive and, thus, rely on estrogen signaling. Estrogen activates an intracellular network composed of many cytoplasmic and nuclear mediators. Some estrogen effects can be mediated by sphingolipids. Estrogen activates sphingosine kinase 1 (SphK1) and amplifies the intracellular concentration of sphingosine-1-phosphate (S1P) in breast cancer cells during stimulation of proliferation and survival. Specifically, Estrogen activates S1P receptors (S1PR) and induces growth factor receptor transactivation. SphK, S1P, and S1PR expression are causally associated with endocrine resistance and progression to advanced tumor stages in ER-positive breast cancers in vivo. Recently, the network of SphK/S1PR was shown to promote the development of ER-negative cancers and breast cancer stem cells, as well as stimulating angiogenesis. Novel findings confirm and broaden our knowledge about the cross-talk between sphingolipids and estrogen network in normal and malignant cells. Current S1PRs therapeutic inhibition was indicated as a promising chemotherapy approach in non-responsive and advanced malignancies. Considering that sphingolipid signaling has a prominent role in terminally differentiated cells, the impact should be considered when designing specific SphK/S1PR inhibitors. This study analyzes the dynamic of the transformation of sphingolipid axis during a transition from normal to pathological condition on the level of the whole organism. The sphingolipid-based mediation and facilitation of global effects of estrogen were critically accented as a bridging mechanism that should be explored in cancer prevention. PMID:29385066

  4. Expansion of Sphingosine Kinase and Sphingosine-1-Phosphate Receptor Function in Normal and Cancer Cells: From Membrane Restructuring to Mediation of Estrogen Signaling and Stem Cell Programming

    Directory of Open Access Journals (Sweden)

    Olga A. Sukocheva

    2018-01-01

    Full Text Available Sphingolipids, sphingolipid metabolizing enzymes, and their receptors network are being recognized as part of the signaling mechanisms, which govern breast cancer cell growth, migration, and survival during chemotherapy treatment. Approximately 70% of breast cancers are estrogen receptor (ER positive and, thus, rely on estrogen signaling. Estrogen activates an intracellular network composed of many cytoplasmic and nuclear mediators. Some estrogen effects can be mediated by sphingolipids. Estrogen activates sphingosine kinase 1 (SphK1 and amplifies the intracellular concentration of sphingosine-1-phosphate (S1P in breast cancer cells during stimulation of proliferation and survival. Specifically, Estrogen activates S1P receptors (S1PR and induces growth factor receptor transactivation. SphK, S1P, and S1PR expression are causally associated with endocrine resistance and progression to advanced tumor stages in ER-positive breast cancers in vivo. Recently, the network of SphK/S1PR was shown to promote the development of ER-negative cancers and breast cancer stem cells, as well as stimulating angiogenesis. Novel findings confirm and broaden our knowledge about the cross-talk between sphingolipids and estrogen network in normal and malignant cells. Current S1PRs therapeutic inhibition was indicated as a promising chemotherapy approach in non-responsive and advanced malignancies. Considering that sphingolipid signaling has a prominent role in terminally differentiated cells, the impact should be considered when designing specific SphK/S1PR inhibitors. This study analyzes the dynamic of the transformation of sphingolipid axis during a transition from normal to pathological condition on the level of the whole organism. The sphingolipid-based mediation and facilitation of global effects of estrogen were critically accented as a bridging mechanism that should be explored in cancer prevention.

  5. Value of post-operative reassessment of estrogen receptor α expression following neoadjuvant chemotherapy with or without gefitinib for estrogen receptor negative breast cancer

    DEFF Research Database (Denmark)

    Bernsdorf, Mogens; Balslev, Eva; Lykkesfeldt, Anne

    2011-01-01

    The NICE trial was designed to evaluate the possible benefits of adding epidermal growth factor receptor targeted therapy to neoadjuvant chemotherapy in patients with estrogen receptor α (ER) negative and operable breast cancer. Preclinical data have suggested that signalling through the Erb......B receptors or downstream effectors may repress ER expression. Here the authors investigated whether gefitinib, given neoadjuvant in combination with epirubicin and cyclophosphamide (EC), could restore ER expression. Eligible patients in the NICE trial were women with unilateral, primary operable, ER negative...... to positive. A change was seen in three patients in the gefitinib (5.1%) and in two patients in the placebo (3.6%) group with a difference of 1.51% (95% CI, -6.1-9.1). Results of the NICE trial have been reported previously. Post-operative reassessment of ER expression changed the assessment of ER status...

  6. Synergism between a half-site and an imperfect estrogen-responsive element, and cooperation with COUP-TFI are required for estrogen receptor (ER) to achieve a maximal estrogen-stimulation of rainbow trout ER gene.

    Science.gov (United States)

    Petit, F G; Métivier, R; Valotaire, Y; Pakdel, F

    1999-01-01

    In all oviparous, liver represents one of the main E2-target tissues where estrogen receptor (ER) constitutes the key mediator of estrogen action. The rainbow trout estrogen receptor (rtER) gene expression is markedly up-regulated by estrogens and the sequences responsible for this autoregulation have been located in a 0.2 kb upstream transcription start site within - 40/- 248 enhancer region. Absence of interference with steroid hormone receptors and tissue-specific factors and a conserved basal transcriptional machinery between yeast and higher eukaryotes, make yeast a simple assay system that will enable determination of important cis-acting regulatory sequences within rtER gene promoter and identification of transcription factors implicated in the regulation of this gene. Deletion analysis allowed to show a synergistic effect between an imperfect estrogen-responsive element (ERE) and a consensus half-ERE to achieve a high hormone-dependent transcriptional activation of the rtER gene promoter in the presence of stably expressed rtER. As in mammalian cells, here we observed a positive regulation of the rtER gene promoter by the chicken ovalbumin upstream promoter-transcription factor I (COUP-TFI) through enhancing autoregulation. Using a point mutation COUP-TFI mutant unable to bind DNA demonstrates that enhancement of rtER gene autoregulation requires the interaction of COUP-TFI to the DNA. Moreover, this enhancement of transcriptional activation by COUP-TFI requires specifically the AF-1 transactivation function of ER and can be observed in the presence of E2 or 4-hydroxytamoxifen but not ICI 164384. Thus, this paper describes the reconstitution of a hormone-responsive transcription unit in yeast in which the regulation of rtER gene promoter could be enhanced by the participation of cis-elements and/or trans-acting factors, such as ER itself or COUP-TF.

  7. Estrogen receptor-alpha-immunoreactive neurons in the mesencephalon, pons and medulla oblongata of the female golden hamster

    NARCIS (Netherlands)

    Boers, J; Gerrits, PO; Holstege, G

    1999-01-01

    Recent studies have revealed brainstem-spinal pathways involved in the generation of receptive behavior in hamster and cat, and the enormous influence of estrogen on these pathways. The present study gives an overview of the location of estrogen receptor-alpha-immunoreactive neurons (ER-alpha-IR) in

  8. [Expression of receptors of estrogens and androgens in the testicular appendices].

    Science.gov (United States)

    Paredes Esteban, R M; Luque Barona, R J; Velasco Sánchez, B; Rodríguez Vargas, J; Lorite, A; García Ruiz, M

    2008-07-01

    The appendices or hidátides of the testicle are structures that are considered an embryonic rest. In testicular hidátide estrogen receivers have been demonstrated but in the epididimys the results vary. Has been theorized that the elevation of the estrogen levels in the puberty can produce an inflammation and torsion of hidátide, nevertheless, in the epididimys in which the estrogen expression is not clear (and also they are twisted) the theory is put in doubt. This controversy takes us to the accomplishment of this work. A prospective study is made in 20 testicular appendices, of which 7 from the epididimys are extirpated of patients to whom an escrotal exploration is made in the development of surgery of processes of the inguino-escrotal channel (hidroceles, hernias). Optical microscopy and inmunohistoquímical study are analyzed by means of using prediluted monoclonales antibodies, for receivers of estrogens, androgens and proliferative index. The results were proceed and analyzed by means of SPSS statistical program. All hidátides, testicular and from the epididimarys expressed receivers for estrogens without significant difference among them, not existing differences as far as the location of receiving sayings within the three compartments of hidátide. The number of estrogen receivers was in relation to the age of the patient. Only hidátides from the epididimys fundamentally expressed receivers of located androgens and at level of ductus. We have not found significant relation between the proliferative index and the expression of estrogen receivers. The proliferative index was more elevated at level of ductus. 1) As much the testicular appendices as those from the epididimays expressed receivers of estrogens at level of the three compartments. It makes think about a same embryonic origin, although only the epididimal ones expressed androgen receivers. 2) the observation of estrogen receivers in both types of hidátides, as well as the relation of the

  9. Polyester monomers lack ability to bind and activate both androgenic and estrogenic receptors as determined by in vitro and in silico methods.

    Science.gov (United States)

    Osimitz, Thomas G; Welsh, William J; Ai, Ni; Toole, Colleen

    2015-01-01

    The paper presents results from the screening of seven monomers used by Eastman Chemical to make various polymers. Ethylene glycol, diethylene glycol, polytetramethylene glycol, isophthalic acid, monosodium-5-sulfoisophthalic acid, 1,4-cyclohexanedicarboxylic acid, and dimethylcyclohexanedicarboxylate were screened for potential androgenicity or estrogenicity. The following studies were conducted: QSAR for binding to the AR and ER, in vitro Androgen Receptor Binding Assay, in vitro Estrogen Receptor Binding Assays (alpha and beta isoforms), in vitro Androgen Receptor Transactivation Assay in human cells, and in vitro Estrogen Receptor Transactivation Assay in human cells. None of the QSAR models predicted that any of the monomers possessed appreciable binding affinity for either AR or ER. Binding assays showed no evidence of interaction with either the AR or the alpha or beta ER receptors. Similarly, the AR and ER transactivation assays were negative. Moreover, six of the seven monomers have been subjected to 13-week and developmental toxicity studies in rats with no androgen- or estrogen-related effects being noted. Given the negative results of the in vitro screening assays (except PMG which demonstrated cytotoxicity) as well as available repeated dose and developmental and reproductive studies, the data suggest that none of the monomers tested exhibit androgenic or estrogenic hazards. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Distinct Effects of Estrogen on Mouse Maternal Behavior: The Contribution of Estrogen Synthesis in the Brain

    Science.gov (United States)

    Murakami, Gen

    2016-01-01

    Estrogen surge following progesterone withdrawal at parturition plays an important role in initiating maternal behavior in various rodent species. Systemic estrogen treatment shortens the latency to onset of maternal behavior in nulliparous female rats that have not experienced parturition. In contrast, nulliparous laboratory mice show rapid onset of maternal behavior without estrogen treatment, and the role of estrogen still remains unclear. Here the effect of systemic estrogen treatment (for 2 h, 1 day, 3 days, and 7 days) after progesterone withdrawal was examined on maternal behavior of C57BL/6 mice. This estrogen regimen led to different effects on nursing, pup retrieval, and nest building behaviors. Latency to nursing was shortened by estrogen treatment within 2 h. Moreover, pup retrieval and nest building were decreased. mRNA expression was also investigated for estrogen receptor α (ERα) and for genes involved in regulating maternal behavior, specifically, the oxytocin receptor (OTR) and vasopressin receptor in the medial amygdala (MeA) and medial preoptic area (MPOA). Estrogen treatment led to decreased ERα mRNA in both regions. Although OTR mRNA was increased in the MeA, OTR and vasopressin receptor mRNA were reduced in the MPOA, showing region-dependent transcription regulation. To determine the mechanisms for the actions of estrogen treatment, the contribution of estrogen synthesis in the brain was examined. Blockade of estrogen synthesis in the brain by systemic letrozole treatment in ovariectomized mice interfered with pup retrieval and nest building but not nursing behavior, indicating different contributions of estrogen synthesis to maternal behavior. Furthermore, letrozole treatment led to an increase in ERα mRNA in the MeA but not in the MPOA, suggesting that involvement of estrogen synthesis is brain region dependent. Altogether, these results suggest that region-dependent estrogen synthesis leads to differential transcriptional activation due

  11. Estrogen and progesterone receptor assay using I-125 estradiol and H-3 promegestone as ligands: Results in female mammary carcinoma

    International Nuclear Information System (INIS)

    Glaubitt, D.; Hienz, H.A.; Bettges, G.; Carmanns, B.; Lichtenberg, T.; Akademisches Lehrkrankenhaus, Krefeld

    1984-01-01

    The determination of estrogen and progesterone receptors in the cytosol of carcinoma of the female breast has predictive value as to the success treatment of the patient. An improved estrogen and progesterone receptor assay using 1-125 labelled estradiol and a H-3 tagged synthetic gestagen (H-3 promegestone) as ligands proved to be highly praticable, especially time-saving. (orig.)

  12. Membrane Estrogen Receptor-α Interacts with Metabotropic Glutamate Receptor Type 1a to Mobilize Intracellular Calcium in Hypothalamic Astrocytes

    Science.gov (United States)

    Kuo, John; Hariri, Omid R.; Bondar, Galyna; Ogi, Julie; Micevych, Paul

    2009-01-01

    Estradiol, acting on a membrane-associated estrogen receptor-α (mERα), induces an increase in free cytoplasmic calcium concentration ([Ca2+]i) needed for progesterone synthesis in hypothalamic astrocytes. To determine whether rapid estradiol signaling involves an interaction of mERα with metabotropic glutamate receptor type 1a (mGluR1a), changes in [Ca2+]i were monitored with the calcium indicator, Fluo-4 AM, in primary cultures of female postpubertal hypothalamic astrocytes. 17β-Estradiol over a range of 1 nm to 100 nm induced a maximal increase in [Ca2+]i flux measured as a change in relative fluorescence [ΔF Ca2+ = 615 ± 36 to 641 ± 47 relative fluorescent units (RFU)], whereas 0.1 nm of estradiol stimulated a moderate [Ca2+]i increase (275 ± 16 RFU). The rapid estradiol-induced [Ca2+]i flux was blocked with 1 μm of the estrogen receptor antagonist ICI 182,780 (635 ± 24 vs. 102 ± 11 RFU, P estradiol-induced membrane signaling in astrocytes. PMID:18948402

  13. CLONING AND IN VITRO EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR α FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    Science.gov (United States)

    In vitro screening assays designed to identify hormone mimics or antagonists typically use mammalian (rat, human) estrogen (ER) and androgen receptors (AR). Although we know that the amino acid sequences of steroid receptors in nonmammalian vertebrates are not identical to the ma...

  14. Tannic Acid Preferentially Targets Estrogen Receptor-Positive Breast Cancer

    Directory of Open Access Journals (Sweden)

    Brian W. Booth

    2013-01-01

    Full Text Available Research efforts investigating the potential of natural compounds in the fight against cancer are growing. Tannic acid (TA belongs to the class of hydrolysable tannins and is found in numerous plants and foods. TA is a potent collagen cross-linking agent; the purpose of this study was to generate TA-cross-linked beads and assess the effects on breast cancer cell growth. Collagen beads were stable at body temperature following crosslinking. Exposure to collagen beads with higher levels of TA inhibited proliferation and induced apoptosis in normal and cancer cells. TA-induced apoptosis involved activation of caspase 3/7 and caspase 9 but not caspase 8. Breast cancer cells expressing the estrogen receptor were more susceptible to the effects of TA. Taken together the results suggest that TA has the potential to become an anti-ER+ breast cancer treatment or preventative agent.

  15. Exclusive nuclear location of estrogen receptors in Squalus testis.

    Science.gov (United States)

    Callard, G V; Mak, P

    1985-01-01

    An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. PMID:3856265

  16. U-shape suppressive effect of phenol red on the epileptiform burst activity via activation of estrogen receptors in primary hippocampal culture.

    Directory of Open Access Journals (Sweden)

    Xu Liu

    Full Text Available Phenol red is widely used in cell culture as a pH indicator. Recently, it also has been reported to have estrogen-like bioactivity and be capable of promoting cell proliferation in different cell lines. However, the effect of phenol red on primary neuronal culture has never been investigated. By using patch clamp technique, we demonstrated that hippocampal pyramidal neurons cultured in neurobasal medium containing no phenol red had large depolarization-associated epileptiform bursting activities, which were rarely seen in neurons cultured in phenol red-containing medium. Further experiment data indicate that the suppressive effect of the phenol red on the abnormal epileptiform burst neuronal activities was U-shape dose related, with the most effective concentration at 28 µM. In addition, this concentration related inhibitory effect of phenol red on the epileptiform neuronal discharges was mimicked by 17-β-estradiol, an estrogen receptor agonist, and inhibited by ICI-182,780, an estrogen receptor antagonist. Our results suggest that estrogen receptor activation by phenol red in the culture medium prevents formation of abnormal, epileptiform burst activity. These studies highlight the importance of phenol red as estrogen receptor stimulator and cautions of careful use of phenol red in cell culture media.

  17. Evaluation of estrogen receptor alpha activation by glyphosate-based herbicide constituents.

    Science.gov (United States)

    Mesnage, Robin; Phedonos, Alexia; Biserni, Martina; Arno, Matthew; Balu, Sucharitha; Corton, J Christopher; Ugarte, Ricardo; Antoniou, Michael N

    2017-10-01

    The safety, including the endocrine disruptive capability, of glyphosate-based herbicides (GBHs) is a matter of intense debate. We evaluated the estrogenic potential of glyphosate, commercial GBHs and polyethoxylated tallowamine adjuvants present as co-formulants in GBHs. Glyphosate (≥10,000 μg/L or 59 μM) promoted proliferation of estrogen-dependent MCF-7 human breast cancer cells. Glyphosate also increased the expression of an estrogen response element-luciferase reporter gene (ERE-luc) in T47D-KBluc cells, which was blocked by the estrogen antagonist ICI 182,780. Commercial GBH formulations or their adjuvants alone did not exhibit estrogenic effects in either assay. Transcriptomics analysis of MCF-7 cells treated with glyphosate revealed changes in gene expression reflective of hormone-induced cell proliferation but did not overlap with an ERα gene expression biomarker. Calculation of glyphosate binding energy to ERα predicts a weak and unstable interaction (-4.10 kcal mol -1 ) compared to estradiol (-25.79 kcal mol -1 ), which suggests that activation of this receptor by glyphosate is via a ligand-independent mechanism. Induction of ERE-luc expression by the PKA signalling activator IBMX shows that ERE-luc is responsive to ligand-independent activation, suggesting a possible mechanism of glyphosate-mediated activation. Our study reveals that glyphosate, but not other components present in GBHs, can activate ERα in vitro, albeit at relatively high concentrations. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Gene expression of estrogen and oxytocin receptors in the uterus of pregnant and parturient bitches

    Energy Technology Data Exchange (ETDEWEB)

    Veiga, G.A.L. [Departamento de Reprodução Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP (Brazil); Milazzotto, M.P. [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, SP (Brazil); Nichi, M.; Lúcio, C.F.; Silva, L.C.G.; Angrimani, D.S.R.; Vannucchi, C.I. [Departamento de Reprodução Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-02-13

    In the canine species, the precise mechanisms of pregnancy maintenance and the initiation of parturition are not completely understood. The expression of genes encoding the receptors for estrogen (ERα mRNA) and oxytocin (OTR mRNA) was studied in the endometrium and myometrium during pregnancy and parturition in dogs. Real-time PCR was performed to quantify the levels of ERα mRNA and OTR mRNA in the uterus of bitches during early (up to 20 days of gestation), mid (20 to 40 days) and late pregnancy (41 to 60 days), and parturition (first stage of labor). All tissues expressed ERα and OTR mRNA, and are thus possibly able to respond to eventual estrogen and oxytocin hormonal stimuli. No statistically significant differences in the expression of ERα mRNA were verified in the endometrium and myometrium throughout pregnancy and parturition, but expression of OTR mRNA increased at both parturition and late pregnancy. We concluded that the increase of endometrial and myometrial OTR mRNA expression in dogs is not an event dependent on estrogenic stimulation. Moreover, the contractility response of the canine uterus to oxytocin begins during pregnancy and maintains myometrial activity. The expression of OTR mRNA in canine uterine tissues varied over time, which supports an interpretation that the sensitivity and response to hormone therapy varies during the course of pregnancy and labor. Further studies are needed to elucidate the factors underlying the synthesis of uterine oxytocin receptors and the possible role of ERβ rather than ERα in the uterine tissues during pregnancy and parturition in dogs.

  19. Gene expression of estrogen and oxytocin receptors in the uterus of pregnant and parturient bitches

    International Nuclear Information System (INIS)

    Veiga, G.A.L.; Milazzotto, M.P.; Nichi, M.; Lúcio, C.F.; Silva, L.C.G.; Angrimani, D.S.R.; Vannucchi, C.I.

    2015-01-01

    In the canine species, the precise mechanisms of pregnancy maintenance and the initiation of parturition are not completely understood. The expression of genes encoding the receptors for estrogen (ERα mRNA) and oxytocin (OTR mRNA) was studied in the endometrium and myometrium during pregnancy and parturition in dogs. Real-time PCR was performed to quantify the levels of ERα mRNA and OTR mRNA in the uterus of bitches during early (up to 20 days of gestation), mid (20 to 40 days) and late pregnancy (41 to 60 days), and parturition (first stage of labor). All tissues expressed ERα and OTR mRNA, and are thus possibly able to respond to eventual estrogen and oxytocin hormonal stimuli. No statistically significant differences in the expression of ERα mRNA were verified in the endometrium and myometrium throughout pregnancy and parturition, but expression of OTR mRNA increased at both parturition and late pregnancy. We concluded that the increase of endometrial and myometrial OTR mRNA expression in dogs is not an event dependent on estrogenic stimulation. Moreover, the contractility response of the canine uterus to oxytocin begins during pregnancy and maintains myometrial activity. The expression of OTR mRNA in canine uterine tissues varied over time, which supports an interpretation that the sensitivity and response to hormone therapy varies during the course of pregnancy and labor. Further studies are needed to elucidate the factors underlying the synthesis of uterine oxytocin receptors and the possible role of ERβ rather than ERα in the uterine tissues during pregnancy and parturition in dogs

  20. Gene expression of estrogen and oxytocin receptors in the uterus of pregnant and parturient bitches.

    Science.gov (United States)

    Veiga, G A L; Milazzotto, M P; Nichi, M; Lúcio, C F; Silva, L C G; Angrimani, D S R; Vannucchi, C I

    2015-04-01

    In the canine species, the precise mechanisms of pregnancy maintenance and the initiation of parturition are not completely understood. The expression of genes encoding the receptors for estrogen (ERα mRNA) and oxytocin (OTR mRNA) was studied in the endometrium and myometrium during pregnancy and parturition in dogs. Real-time PCR was performed to quantify the levels of ERα mRNA and OTR mRNA in the uterus of bitches during early (up to 20 days of gestation), mid (20 to 40 days) and late pregnancy (41 to 60 days), and parturition (first stage of labor). All tissues expressed ERα and OTR mRNA, and are thus possibly able to respond to eventual estrogen and oxytocin hormonal stimuli. No statistically significant differences in the expression of ERα mRNA were verified in the endometrium and myometrium throughout pregnancy and parturition, but expression of OTR mRNA increased at both parturition and late pregnancy. We concluded that the increase of endometrial and myometrial OTR mRNA expression in dogs is not an event dependent on estrogenic stimulation. Moreover, the contractility response of the canine uterus to oxytocin begins during pregnancy and maintains myometrial activity. The expression of OTR mRNA in canine uterine tissues varied over time, which supports an interpretation that the sensitivity and response to hormone therapy varies during the course of pregnancy and labor. Further studies are needed to elucidate the factors underlying the synthesis of uterine oxytocin receptors and the possible role of ERβ rather than ERα in the uterine tissues during pregnancy and parturition in dogs.

  1. Genome-wide identification of estrogen receptor alpha-binding sites in mouse liver

    DEFF Research Database (Denmark)

    Gao, Hui; Fält, Susann; Sandelin, Albin

    2007-01-01

    We report the genome-wide identification of estrogen receptor alpha (ERalpha)-binding regions in mouse liver using a combination of chromatin immunoprecipitation and tiled microarrays that cover all nonrepetitive sequences in the mouse genome. This analysis identified 5568 ERalpha-binding regions...... genes. The majority of ERalpha-binding regions lie in regions that are evolutionarily conserved between human and mouse. Motif-finding algorithms identified the estrogen response element, and variants thereof, together with binding sites for activator protein 1, basic-helix-loop-helix proteins, ETS...... signaling in mouse liver, by characterizing the first step in this signaling cascade, the binding of ERalpha to DNA in intact chromatin....

  2. Antibody Probes to Estrogen Receptor-Alpha Transcript-Specific Upstream Peptides: Alternate ER-Alpha Promoter Use and Breast Cancer Etiology/Outcome

    National Research Council Canada - National Science Library

    Pentecost, Brian

    2002-01-01

    Positive Estrogen Receptor alpha (ER) status correlates with a reduced incidence of breast cancer recurrence in the first years after resection of tumors, and predicts a favorable response to adjuvant anti-estrogens...

  3. CDNA CLONING OF FATHEAD MINNOW (PIMEPHALES PROMELAS) ESTROGEN AND ANDROGEN RECEPTORS FOR USE IN STEROID RECEPTOR EXTRAPOLATION STUDIES FOR ENDOCRINE DISRUPTING CHEMICALS

    Science.gov (United States)

    cDNA Cloning of Fathead minnow (Pimephales promelas) Estrogen and Androgen Receptors for Use in Steroid Receptor Extrapolation Studies for Endocrine Disrupting Chemicals. Wilson, V.S.1,, Korte, J.2, Hartig P. 1, Ankley, G.T.2, Gray, L.E., Jr 1, , and Welch, J.E.1. 1U.S...

  4. Epidermal growth factor receptor signalling in human breast cancer cells operates parallel to estrogen receptor α signalling and results in tamoxifen insensitive proliferation

    International Nuclear Information System (INIS)

    Moerkens, Marja; Zhang, Yinghui; Wester, Lynn; Water, Bob van de; Meerman, John HN

    2014-01-01

    Tamoxifen resistance is a major problem in the treatment of estrogen receptor (ER) α -positive breast cancer patients. Although the mechanisms behind tamoxifen resistance are still not completely understood, clinical data suggests that increased expression of receptor tyrosine kinases is involved. Here, we studied the estrogen and anti-estrogen sensitivity of human breast cancer MCF7 cells that have a moderate, retroviral-mediated, ectopic expression of epidermal growth factor receptor (MCF7-EGFR). Proliferation of MCF7-EGFR and parental cells was induced by 17β-estradiol (E2), epidermal growth factor (EGF) or a combination of these. Inhibition of proliferation under these conditions was investigated with 4-hydroxy-tamoxifen (TAM) or fulvestrant at 10 -12 to 10 -6 M. Cells were lysed at different time points to determine the phosphorylation status of EGFR, MAPK 1/3 , AKT and the expression of ERα. Knockdown of target genes was established using smartpool siRNAs. Transcriptomics analysis was done 6 hr after stimulation with growth factors using Affymetrix HG-U133 PM array plates. While proliferation of parental MCF7 cells could only be induced by E2, proliferation of MCF7-EGFR cells could be induced by either E2 or EGF. Treatment with TAM or fulvestrant did significantly inhibit proliferation of MCF7-EGFR cells stimulated with E2 alone. EGF treatment of E2/TAM treated cells led to a marked cell proliferation thereby overruling the anti-estrogen-mediated inhibition of cell proliferation. Under these conditions, TAM however did still inhibit ERα- mediated transcription. While siRNA-mediated knock-down of EGFR inhibited the EGF- driven proliferation under TAM/E2/EGF condition, knock down of ERα did not. The TAM resistant cell proliferation mediated by the conditional EGFR-signaling may be dependent on the PI3K/Akt pathway but not the MEK/MAPK pathway, since a MEK inhibitor (U0126), did not block the proliferation. Transcriptomic analysis under the various E2/TAM

  5. Thioredoxin and thioredoxin reductase influence estrogen receptor α-mediated gene expression in human breast cancer cells

    OpenAIRE

    Rao, Abhi K; Ziegler, Yvonne S; McLeod, Ian X; Yates, John R; Nardulli, Ann M

    2009-01-01

    Accumulation of reactive oxygen species (ROS) in cells damages resident proteins, lipids, and DNA. In order to overcome the oxidative stress that occurs with ROS accumulation, cells must balance free radical production with an increase in the level of antioxidant enzymes that convert free radicals to less harmful species. We identified two antioxidant enzymes, thioredoxin (Trx) and Trx reductase (TrxR), in a complex associated with the DNA-bound estrogen receptor α (ERα). Western analysis and...

  6. Beta-Estradiol Regulates Voltage-Gated Calcium Channels and Estrogen Receptors in Telocytes from Human Myometrium

    Directory of Open Access Journals (Sweden)

    Adela Banciu

    2018-05-01

    Full Text Available Voltage-gated calcium channels and estrogen receptors are essential players in uterine physiology, and their association with different calcium signaling pathways contributes to healthy and pathological conditions of the uterine myometrium. Among the properties of the various cell subtypes present in human uterine myometrium, there is increasing evidence that calcium oscillations in telocytes (TCs contribute to contractile activity and pregnancy. Our study aimed to evaluate the effects of beta-estradiol on voltage-gated calcium channels and estrogen receptors in TCs from human uterine myometrium and to understand their role in pregnancy. For this purpose, we employed patch-clamp recordings, ratiometric Fura-2-based calcium imaging analysis, and qRT-PCR techniques for the analysis of cultured human myometrial TCs derived from pregnant and non-pregnant uterine samples. In human myometrial TCs from both non-pregnant and pregnant uterus, we evidenced by qRT-PCR the presence of genes encoding for voltage-gated calcium channels (Cav3.1, Ca3.2, Cav3.3, Cav2.1, estrogen receptors (ESR1, ESR2, GPR30, and nuclear receptor coactivator 3 (NCOA3. Pregnancy significantly upregulated Cav3.1 and downregulated Cav3.2, Cav3.3, ESR1, ESR2, and NCOA3, compared to the non-pregnant condition. Beta-estradiol treatment (24 h, 10, 100, 1000 nM downregulated Cav3.2, Cav3.3, Cav1.2, ESR1, ESR2, GRP30, and NCOA3 in TCs from human pregnant uterine myometrium. We also confirmed the functional expression of voltage-gated calcium channels by patch-clamp recordings and calcium imaging analysis of TCs from pregnant human myometrium by perfusing with BAY K8644, which induced calcium influx through these channels. Additionally, we demonstrated that beta-estradiol (1000 nM antagonized the effect of BAY K8644 (2.5 or 5 µM in the same preparations. In conclusion, we evidenced the presence of voltage-gated calcium channels and estrogen receptors in TCs from non-pregnant and pregnant

  7. Beta-Estradiol Regulates Voltage-Gated Calcium Channels and Estrogen Receptors in Telocytes from Human Myometrium.

    Science.gov (United States)

    Banciu, Adela; Banciu, Daniel Dumitru; Mustaciosu, Cosmin Catalin; Radu, Mihai; Cretoiu, Dragos; Xiao, Junjie; Cretoiu, Sanda Maria; Suciu, Nicolae; Radu, Beatrice Mihaela

    2018-05-09

    Voltage-gated calcium channels and estrogen receptors are essential players in uterine physiology, and their association with different calcium signaling pathways contributes to healthy and pathological conditions of the uterine myometrium. Among the properties of the various cell subtypes present in human uterine myometrium, there is increasing evidence that calcium oscillations in telocytes (TCs) contribute to contractile activity and pregnancy. Our study aimed to evaluate the effects of beta-estradiol on voltage-gated calcium channels and estrogen receptors in TCs from human uterine myometrium and to understand their role in pregnancy. For this purpose, we employed patch-clamp recordings, ratiometric Fura-2-based calcium imaging analysis, and qRT-PCR techniques for the analysis of cultured human myometrial TCs derived from pregnant and non-pregnant uterine samples. In human myometrial TCs from both non-pregnant and pregnant uterus, we evidenced by qRT-PCR the presence of genes encoding for voltage-gated calcium channels (Cav3.1, Ca3.2, Cav3.3, Cav2.1), estrogen receptors (ESR1, ESR2, GPR30), and nuclear receptor coactivator 3 (NCOA3). Pregnancy significantly upregulated Cav3.1 and downregulated Cav3.2, Cav3.3, ESR1, ESR2, and NCOA3, compared to the non-pregnant condition. Beta-estradiol treatment (24 h, 10, 100, 1000 nM) downregulated Cav3.2, Cav3.3, Cav1.2, ESR1, ESR2, GRP30, and NCOA3 in TCs from human pregnant uterine myometrium. We also confirmed the functional expression of voltage-gated calcium channels by patch-clamp recordings and calcium imaging analysis of TCs from pregnant human myometrium by perfusing with BAY K8644, which induced calcium influx through these channels. Additionally, we demonstrated that beta-estradiol (1000 nM) antagonized the effect of BAY K8644 (2.5 or 5 µM) in the same preparations. In conclusion, we evidenced the presence of voltage-gated calcium channels and estrogen receptors in TCs from non-pregnant and pregnant human uterine

  8. Artonin E and Structural Analogs from Artocarpus Species Abrogates Estrogen Receptor Signaling in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Imaobong Etti

    2016-06-01

    Full Text Available The increasing rate of mortality ensued from breast cancer has encouraged research into safer and efficient therapy. The human Estrogen receptor α has been implicated in the majority of reported breast cancer cases. Molecular docking employing Glide, Schrodinger suite 2015, was used to study the binding affinities of small molecules from the Artocarpus species after their drug-like properties were ascertained. The structure of the ligand-binding domain of human Estrogen receptor α was retrieved from Protein Data Bank while the structures of compounds were collected from PubChem database. The binding interactions of the studied compounds were reported as well as their glide scores. The best glide scored ligand, was Artonin E with a score of −12.72 Kcal when compared to other studied phytomolecules and it evoked growth inhibition of an estrogen receptor positive breast cancer cells in submicromolar concentration (3.8–6.9 µM in comparison to a reference standard Tamoxifen (18.9–24.1 µM within the tested time point (24–72 h. The studied ligands, which had good interactions with the target receptor, were also drug-like when compared with 95% of orally available drugs with the exception of Artoelastin, whose predicted physicochemical properties rendered it less drug-like. The in silico physicochemical properties, docking interactions and growth inhibition of the best glide scorer are indications of the anti-breast cancer relevance of the studied molecules.

  9. Estradiol upregulates calcineurin expression via overexpression of estrogen receptor alpha gene in systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Hui-Li Lin

    2011-04-01

    Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disease primarily affecting women (9:1 compared with men. To investigate the influence of female sex hormone estrogen on the development of female-biased lupus, we compared the expression of estrogen receptor alpha (ERα gene and protein levels as well as expression of T-cell activation gene calcineurin in response to estrogen in peripheral blood lymphocytes (PBLs from SLE patients and normal controls. PBLs were isolated from 20 female SLE patients and 6 normal female controls. The amount of ERα protein in PBL was measured by flow cytometry. The expression of ERα and calcineurin messenger RNA was measured by semi-quantitative reverse transcription-polymerase chain reaction. Calcineurin phosphatase activity was measured by calcineurin assay kit. The expression of ERα messenger RNA and ERα protein was significantly increased (p=0.001 and p=0.023, respectively in PBL from SLE patients compared with that from normal controls. In addition, the basal calcineurin in PBL from SLE patients was significantly higher (p=0.000 than that from normal controls, and estrogen-induced expression of calcineurin was increased (p=0.007 in PBL from SLE patients compared with that from normal controls, a 3.15-fold increase. This increase was inhibited by the ERα antagonism ICI 182,780. The effects of ER antagonism were also found in calcineurin activity. These data suggest that overexpression of ERα gene and enhanced activation of calcineurin in response to estrogen in PBL may contribute to the pathogenesis of female dominant in SLE.

  10. MEL-18 loss mediates estrogen receptor-α downregulation and hormone independence.

    Science.gov (United States)

    Lee, Jeong-Yeon; Won, Hee-Young; Park, Ji-Hye; Kim, Hye-Yeon; Choi, Hee-Joo; Shin, Dong-Hui; Kang, Ju-Hee; Woo, Jong-Kyu; Oh, Seung-Hyun; Son, Taekwon; Choi, Jin-Woo; Kim, Sehwan; Kim, Hyung-Yong; Yi, Kijong; Jang, Ki-Seok; Oh, Young-Ha; Kong, Gu

    2015-05-01

    The polycomb protein MEL-18 has been proposed as a tumor suppressor in breast cancer; however, its functional relevance to the hormonal regulation of breast cancer remains unknown. Here, we demonstrated that MEL-18 loss contributes to the hormone-independent phenotype of breast cancer by modulating hormone receptor expression. In multiple breast cancer cohorts, MEL-18 was markedly downregulated in triple-negative breast cancer (TNBC). MEL-18 expression positively correlated with the expression of luminal markers, including estrogen receptor-α (ER-α, encoded by ESR1). MEL-18 loss was also associated with poor response to antihormonal therapy in ER-α-positive breast cancer. Furthermore, whereas MEL-18 loss in luminal breast cancer cells resulted in the downregulation of expression and activity of ER-α and the progesterone receptor (PR), MEL-18 overexpression restored ER-α expression in TNBC. Consistently, in vivo xenograft experiments demonstrated that MEL-18 loss induces estrogen-independent growth and tamoxifen resistance in luminal breast cancer, and that MEL-18 overexpression confers tamoxifen sensitivity in TNBC. MEL-18 suppressed SUMOylation of the ESR1 transactivators p53 and SP1, thereby driving ESR1 transcription. MEL-18 facilitated the deSUMOylation process by inhibiting BMI-1/RING1B-mediated ubiquitin-proteasomal degradation of SUMO1/sentrin-specific protease 1 (SENP1). These findings demonstrate that MEL-18 is a SUMO-dependent regulator of hormone receptors and suggest MEL-18 expression as a marker for determining the antihormonal therapy response in patients with breast cancer.

  11. Anti-Inflammatory Effects of Tanshinone IIA on Atherosclerostic Vessels of Ovariectomized ApoE-/- Mice are Mediated by Estrogen Receptor Activation and Through the ERK Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2015-03-01

    Full Text Available Aims: Estrogen plays a protective role in atherosclerosis. Our preliminary work demonstrated that the active conformation of Tanshinone IIA(TanIIA is similar to the 17ß-estradiol and it can bind to the estrogen receptor. Here, we hypothesized that Tanshinone IIA might have anti-inflammatory and anti-oxidative effects in atherosclerosis, mediated through estrogen receptor activation. Methods: Subjects for this study were 120 apoE-/- female mice and 20 C57/BL female mice. The apoE-/- mice were ovariectomized (OVX and the C57/BL mice were sham ovariectomized. The sham OVX mice were maintained on a normal diet (NOR group. The OVX apoE-/- mice were fed a high fat diet and randomly divided into 6 groups: Model (MOD group which was fed a high fat diet only, E2 group were given estrogen (E2 0.13mg/kg/d; E2+ICI group were given E2:0.13mg/kg/d and ICI182780:65mg/kg/m; TLD group (TanIIA low dose were given TanIIA: 30mg/kg/d; THD group (TanIIA high dose were given TanIIA:60mg/kg/d; and TLD+ICI group were given TanIIA 30mg/kg/d and ICI182780 65mg/kg/m. After three months of treatment, the aorta and the blood of the mice from each group was collected. The aorta were used for testing the lipid deposition by using hematoxylin and eosin(HE and oil red O staining and for testing the expression of p-ERK1/2 by Western blot. The blood was used for testing the serum cholesterol, superoxide dismutase (SOD, methane dicarboxylic aldehyde (MDA, nuclear factor kappa (NF-κB, soluble intercellular cell adhesion molecule-1 (sICAM-1, activating protein-1 (AP-1, E-selectin and 17ß-estradiol in serum. Results: Tanshinone IIA significantly reduced the lipid deposition in aorta, decreased the levels of total cholesterol (TC, triglyceride (TG, low density lipoprotein (LDL, very low density lipoprotein (VLDL, MDA, NF-κB, sICAM-1, AP-1, and E-selectin in serum but increased the levels of high density lipoprotein (HDL and SOD in serum. Tanshinone IIA also suppressed the

  12. Demethylation of Circulating Estrogen Receptor Alpha Gene in Cerebral Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Hsiu-Fen Lin

    Full Text Available Estrogen is involved in neuron plasticity and can promote neuronal survival in stroke. Its actions are mostly exerted via estrogen receptor alpha (ERα. Previous animal studies have shown that ERα is upregulated by DNA demethylation following ischemic injury. This study investigated the methylation levels in the ERα promoter in the peripheral blood of ischemic stroke patients.The study included 201 ischemic stroke patients, and 217 age- and sex-comparable healthy controls. The quantitative methylation level in the 14 CpG sites of the ERα promoter was measured by pyrosequencing in each participant. Multivariate regression model was used to adjust for stroke traditional risk factors. Stroke subtypes and sex-specific analysis were also conducted.The results demonstrated that the stroke cases had a lower ERα methylation level than controls in all 14 CpG sites, and site 13 and site 14 had significant adjusted p-values of 0.035 and 0.026, respectively. Stroke subtypes analysis showed that large-artery atherosclerosis and cardio-embolic subtypes had significantly lower methylation levels than the healthy controls at CpG site 5, site 9, site 12, site 13 and site 14 with adjusted p = 0.039, 0.009, 0.025, 0.046 and 0.027 respectively. However, the methylation level for the patients with small vessel subtype was not significant. We combined the methylation data from the above five sites for further sex-specific analysis. The results showed that the significant association only existed in women (adjusted p = 0.011, but not in men (adjusted p = 0.300.Female stroke cases have lower ERα methylation levels than those in the controls, especially in large-artery and cardio-embolic stroke subtypes. The study implies that women suffering from ischemic stroke of specific subtype may undergo different protective mechanisms to reduce the brain injury.

  13. Estrogen: The necessary evil for human health, and ways to tame it.

    Science.gov (United States)

    Patel, Seema; Homaei, Ahmad; Raju, Akondi Butchi; Meher, Biswa Ranjan

    2018-06-01

    Estrogen is a pivotal enzyme for survival and health in both genders, though their quantum, tropism, tissue-specific distribution, and receptor affinity varies with different phases of life. Converted from androgen via aromatase enzyme, this hormone is indispensable to glucose homeostasis, immune robustness, bone health, cardiovascular health, fertility, and neural functions. However, estrogen is at the center of almost all human pathologies as well-infectious, autoimmune, metabolic to degenerative. Both hypo and hyper level of estrogen has been linked to chronic and acute diseases. While normal aging is supposed to lower its level, leading to tissue degeneration (bone, muscle, neural etc.), and metabolite imbalance (glucose, lipid etc.), the increment in inflammatory agents in day-to-day life are enhancing the estrogen (or estrogen mimic) level, fueling 'estrogen dominance'. The resultant excess estrogen is inducing an overexpression of estrogen receptors (ERα and ERβ), harming tissues, leading to autoimmune diseases, and neoplasms. The unprecedented escalation in the polycystic ovary syndrome, infertility, breast cancer, ovary cancer, and gynecomastia cases are indicating that this sensitive hormone is getting exacerbated. This critical review is an effort to analyze the dual, and opposing facets of estrogen, via understanding its crosstalk with other hormones, enzymes, metabolites, and drugs. Why estrogen level correction is no trivial task, and how it can be restored to normalcy by a disciplined lifestyle with wise dietary and selective chemical usage choices has been discussed. Overall, our current state of knowledge does not disclose the full picture of estrogen's pleiotropic importance. Hence, this review should be a resource for general public as well as researchers to work in that direction. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  14. MOLECULAR DOCKING OF COMPOUNDS FROM Chaetomium Sp. AGAINST HUMAN ESTROGEN RECEPTOR ALPHA IN SEARCHING ANTI BREAST CANCER

    Directory of Open Access Journals (Sweden)

    Maywan Hariono

    2016-05-01

    Full Text Available A study on molecular docking-based virtual screening has been conducted to select virtual hit of compounds, reported its existence in fungal endophytes of Chaetomium sp. as cytotoxic agent of breast cancer. The ligands were docked into Human Estrogen Receptor alpha (HERa as the protein which regulates the breast cancer growth via estradiol-estrogen receptor binding intervention. The results showed that two compounds bearing xanthone and two compounds bearing benzonaphtyridinedione scaffolds were selected as virtual hit ligands for HERa leading to the conclusion that these compounds were good to be developed as anti breast cancer.

  15. The role of estrogen in cutaneous ageing and repair.

    Science.gov (United States)

    Wilkinson, Holly N; Hardman, Matthew J

    2017-09-01

    Combined advances in modern medical practice and increased human longevity are driving an ever-expanding elderly population. Females are particularly at risk of age-associated pathology, spending more of their lives in a post-menopausal state. Menopause, denoted by a rapid decline in serum sex steroid levels, accelerates biological ageing across the body's tissues. Post-menopause physiological changes are particularly noticeable in the skin, which loses structural architecture and becomes prone to damage. The sex steroid most widely discussed as an intrinsic contributor to skin ageing and pathological healing is 17β-estradiol (or estrogen), although many others are involved. Estrogen deficiency is detrimental to many wound-healing processes, notably inflammation and re-granulation, while exogenous estrogen treatment widely reverses these effects. Over recent decades, many of the molecular and cellular correlates to estrogen's beneficial effect on normal skin homeostasis and wound healing have been reported. However, disparities still exist, particularly in the context of mechanistic studies investigating estrogen receptor signalling and its potential cellular effects. New molecular techniques, coupled with increased understanding of estrogen in skin biology, will provide further opportunities to develop estrogen receptor-targeted therapeutics. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Estrogen and progesterone receptor levels in nonneoplastic breast epithelium of breast cancer cases versus benign breast biopsy controls

    International Nuclear Information System (INIS)

    Woolcott, Christy G; SenGupta, Sandip K; Hanna, Wedad M; Aronson, Kristan J

    2008-01-01

    Previous studies and biological mechanisms of carcinogenesis suggest that the steroid receptor content of benign breast epithelium may be related to breast cancer risk. The objective in this study was to compare the levels of estrogen receptor-α (ER) and progesterone receptor (PR) in nonneoplastic breast epithelium between breast cancer cases and biopsy controls. Between 1995 and 1997 at two sites (Women's College Hospital in Toronto and Kingston General Hospital), 667 women who were scheduled for diagnostic excisional breast biopsies completed a questionnaire providing personal information and agreed to allow analysis of routinely resected tissue. Histological slides with nonneoplastic epithelium were available for 101 cancer cases and 200 biopsy controls in Toronto and for 105 cancer cases and 119 controls in Kingston. Nonneoplastic epithelium was examined with immunohistochemical assays to determine the percent of epithelial cells staining for ER and PR. Unconditional logistic regression was used to calculate odds ratios (OR) stratified by study site. The ER content of nonneoplastic tissue was higher in cases than biopsy controls in unadjusted analyses; after adjustment for age, however, a weak association remained in only one of the study sites. After adjustment for age, the PR content of nonneoplastic tissue was slightly lower in breast cancer cases than controls in one study site. Furthermore, this inverse association was confined to women with PR negative breast cancer in comparison to the controls. No interaction between ER and PR content of nonneoplastic tissue was observed in relation to the odds of having breast cancer. The results of this study are consistent with only a slight indication of increased ER levels in nonneoplastic tissue in breast cancer cases relative to controls. This study contributes to the understanding of breast cancer by examining both ER and PR in nonneoplastic tissue. Limitations remain, however, such as the necessity of

  17. Induction of aryl hydrocarbon receptor-mediated and estrogen receptor-mediated activities, and modulation of cell proliferation by dinaphthofurans

    Czech Academy of Sciences Publication Activity Database

    Vondráček, Jan; Chramostová, Kateřina; Plíšková, M.; Bláha, L.; Brack, W.; Kozubík, Alois; Machala, M.

    2004-01-01

    Roč. 23, č. 9 (2004), s. 2214-2220 ISSN 0730-7268 R&D Projects: GA ČR GA525/03/1527 Institutional research plan: CEZ:AV0Z5004920 Keywords : aryl hydrocarbon receptor-mediated activity * estrogenicity * intercellular communication inhibition Subject RIV: BO - Biophysics Impact factor: 2.121, year: 2004

  18. Impact of estrogen receptor α gene and oxytocin receptor gene polymorphisms on female sexuality

    Directory of Open Access Journals (Sweden)

    Anastasia K Armeni

    2017-02-01

    Full Text Available Over the past decades, research attention has increasingly been paid to the neurobiological component of sexual behavior. The aim of the present study was to investigate the correlation of estrogen receptor α (ERA gene polymorphism (rs2234693-PvuII (T→C substitution and oxytocin receptor gene polymorphism (rs53576 (G→A substitution with sexuality parameters of young, healthy women. One hundred thirty-three Greek heterosexual women, students in higher education institutions, 20–25 years of age, sexually active, with normal menstrual cycles (28–35 days, were recruited in the study. Exclusion criteria were chronic and/or major psychiatric diseases, use of oral contraceptive pills (OCs, polycystic ovary syndrome (PCOS, thyroid diseases as well as drugs that are implicated in hypothalamus–pituitary–gonadal axis. T allele (wildtype of rs2234693 (PvuII polymorphism of ERA gene was correlated with increased levels of arousal and lubrication, whereas A allele (polymorphic of rs53576 (OXTR polymorphism was correlated with increased arousal levels. The simultaneous presence of both T allele of rs2234693 (PvuII and A allele of rs53576 (OXTR polymorphisms (T + A group was correlated with increased arousal, orgasm levels as well as female sexual function index full score. To our knowledge, this is the first study to investigate the interaction between ERA and OXTR with regard to sexual function in women. Female sexuality is a complex behavioral trait that encompasses both biological and psychological components. It seems that variability in female sexual response stems from genetic variability that characterizes endocrine, neurotransmitter and central nervous system influences.

  19. Presence of estrogen receptors in human myeloid monocytic cells (THP-1 cell line).

    Science.gov (United States)

    Cutolo, M; Villaggio, B; Bisso, A; Sulli, A; Coviello, D; Dayer, J M

    2001-01-01

    To test THP-1 cells for the presence of estrogen receptors (ER) since studies have demonstrated in vivo and in vitro, the influence of estrogens on cells involved in immune response (i.e. macrophages), and since it has been demonstrated that human myeloid monocytic THP-1 cells acquire phenotypic and functional macrophage-like features after incubation with several cytokines or pharmacological agents. Stimulation of THP-1 cells with phorbol myristate acetate (PMA) to prompt their differentiation into macrophage-like cells and evaluation of the possible induction of ER. The expression of ER was analyzed by immunocytochemical assay, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. After stimulation by PMA, the human myeloid monocytic THP-1 cells showed the presence of ER, together with markers of monocytic cell differentiation such as CD68, CD54 and HLA-DR. Estrogen effects may be exerted directly through ER on monocytes/macrophages. PMA-treated THP-1 cells may constitute a useful in vitro model to determine the effects of estrogens on macrophage-like cells and their implications in the inflammatory and immune processes.

  20. Calmodulin-like protein 3 is an estrogen receptor alpha coregulator for gene expression and drug response in a SNP, estrogen, and SERM-dependent fashion.

    Science.gov (United States)

    Qin, Sisi; Ingle, James N; Liu, Mohan; Yu, Jia; Wickerham, D Lawrence; Kubo, Michiaki; Weinshilboum, Richard M; Wang, Liewei

    2017-08-18

    We previously performed a case-control genome-wide association study in women treated with selective estrogen receptor modulators (SERMs) for breast cancer prevention and identified single nucleotide polymorphisms (SNPs) in ZNF423 as potential biomarkers for response to SERM therapy. The ZNF423rs9940645 SNP, which is approximately 200 bp away from the estrogen response elements, resulted in the SNP, estrogen, and SERM-dependent regulation of ZNF423 expression and, "downstream", that of BRCA1. Electrophoretic mobility shift assay-mass spectrometry was performed to identify proteins binding to the ZNF423 SNP and coordinating with estrogen receptor alpha (ERα). Clustered, regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing was applied to generate ZR75-1 breast cancer cells with different ZNF423 SNP genotypes. Both cultured cells and mouse xenograft models with different ZNF423 SNP genotypes were used to study the cellular responses to SERMs and poly(ADP-ribose) polymerase (PARP) inhibitors. We identified calmodulin-like protein 3 (CALML3) as a key sensor of this SNP and a coregulator of ERα, which contributes to differential gene transcription regulation in an estrogen and SERM-dependent fashion. Furthermore, using CRISPR/Cas9-engineered ZR75-1 breast cancer cells with different ZNF423 SNP genotypes, striking differences in cellular responses to SERMs and PARP inhibitors, alone or in combination, were observed not only in cells but also in a mouse xenograft model. Our results have demonstrated the mechanism by which the ZNF423 rs9940645 SNP might regulate gene expression and drug response as well as its potential role in achieving more highly individualized breast cancer therapy.

  1. Evaluation of the Biological Activity of Opuntia ficus indica as a Tissue- and Estrogen Receptor Subtype-Selective Modulator.

    Science.gov (United States)

    An, Byoung Ha; Jeong, Hyesoo; Zhou, Wenmei; Liu, Xiyuan; Kim, Soolin; Jang, Chang Young; Kim, Hyun-Sook; Sohn, Johann; Park, Hye-Jin; Sung, Na-Hye; Hong, Cheol Yi; Chang, Minsun

    2016-06-01

    Phytoestrogens are selective estrogen receptor modulators (SERMs) with potential for use in hormone replacement therapy (HRT) to relieve peri/postmenopausal symptoms. This study was aimed at elucidating the molecular mechanisms underlying the SERM properties of the extract of Korean-grown Opuntia ficus-indica (KOFI). The KOFI extract induced estrogen response element (ERE)-driven transcription in breast and endometrial cancer cell lines and the expression of endogenous estrogen-responsive genes in breast cancer cells. The flavonoid content of different KOFI preparations affected ERE-luciferase activities, implying that the flavonoid composition likely mediated the estrogenic activities in cells. Oral administration of KOFI decreased the weight gain and levels of both serum glucose and triglyceride in ovariectomized (OVX) rats. Finally, KOFI had an inhibitory effect on the 17β-estradiol-induced proliferation of the endometrial epithelium in OVX rats. Our data demonstrate that KOFI exhibited SERM activity with no uterotrophic side effects. Therefore, KOFI alone or in combination with other botanical supplements, vitamins, or minerals may be an effective and safe alternative active ingredient to HRTs, for the management of postmenopausal symptoms. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Estrogen receptor alpha regulates expression of the breast cancer 1 associated ring domain 1 (BARD1) gene through intronic DNA sequence.

    Science.gov (United States)

    Creekmore, Amy L; Ziegler, Yvonne S; Bonéy, Jamie L; Nardulli, Ann M

    2007-03-15

    We have used a chromatin immunoprecipitation (ChIP)-based cloning strategy to isolate and identify genes associated with estrogen receptor alpha (ERalpha) in MCF-7 human breast cancer cells. One of the gene regions isolated was a 288bp fragment from the ninth intron of the breast cancer 1 associated ring domain (BARD1) gene. We demonstrated that ERalpha associated with this region of the endogenous BARD 1 gene in MCF-7 cells, that ERalpha bound to three of five ERE half sites located in the 288bp BARD1 region, and that this 288bp BARD1 region conferred estrogen responsiveness to a heterologous promoter. Importantly, treatment of MCF-7 cells with estrogen increased BARD1 mRNA and protein levels. These findings demonstrate that ChIP cloning strategies can be utilized to successfully isolate regulatory regions that are far removed from the transcription start site and assist in identifying cis elements involved in conferring estrogen responsiveness.

  3. Pelargonidin Improves Passive Avoidance Task Performance in a Rat Amyloid Beta25-35 Model of Alzheimer’s Disease Via Estrogen Receptor Independent Pathways

    Directory of Open Access Journals (Sweden)

    Hamid Sohanaki

    2016-05-01

    Full Text Available Alzheimer’s disease (AD is a disorder with multiple pathophysiological causes, destructive outcomes, and no available definitive cure. Pelargonidin (Pel, an anthocyanin derivative, is an estrogen receptor agonist with little estrogen side effects. This study was designed to assess Pel memory enhancing effects on the a rat Amyloid Beta25-35 (Aβ intrahippocampal microinjections model of AD in the passive avoidance task performance paradigm and further evaluate the potential estrogen receptor role on the memory-evoking compound. Equally divided rats were assigned to 5 groups of sham, Aβ intrahippocampal microinjected, Pel pretreated (10 mg/kg; P.O, α estrogen antagonist intra-cerebrovascular (i.c.v. microinjected, and β estrogen antagonist (i.c.v microinjected animals. Intrahippocampal microinjections of Aβ were adopted to provoke AD model. Passive avoidance task test was also used to assess memory performance. Pel pretreatment prior to Aβ microinjections significantly improved step-through latency (P<0.001 in passive avoidance test. In α and β estrogen, antagonists received animals, passive avoidance task performance was not statistically changed (P=0.11 & P=0.41 respectively compared to Pel pretreated and sham animals. Our results depicted that Pel improves Aβ induced memory dysfunction in passive avoidance test performance through estrogen receptor independently related pathways.

  4. Identification of ten variants associated with risk of estrogen-receptor-negative breast cancer

    NARCIS (Netherlands)

    Milne, Roger L.; Kuchenbaecker, Karoline B.; Michailidou, Kyriaki; Beesley, Jonathan; Kar, Siddhartha; Lindström, Sara; Hui, Shirley; Lemaçon, Audrey; Soucy, Penny; Dennis, Joe; Jiang, Xia; Rostamianfar, Asha; Finucane, Hilary K; Bolla, Manjeet K.; McGuffog, Lesley; Wang, Qin; Aalfs, Cora M.; Adams, Marcia; Adlard, Julian; Agata, Simona; Ahmed, Shahana; Ahsan, Habibul; Aittomäki, Kristiina; Al-Ejeh, Fares; Allen, Jamie; Ambrosone, Christine B.; Amos, Christopher I; Andrulis, Irene L.; Anton-Culver, Hoda; Antonenkova, Natalia N.; Arndt, Volker; Arnold, Norbert; Aronson, Kristan J; Auber, Bernd; Auer, Paul L.; Ausems, Margreet G E M; Azzollini, Jacopo; Bacot, François; Balmaña, Judith; Barile, Monica; Barjhoux, Laure; Barkardottir, Rosa B.; Barrdahl, Myrto; Barnes, Daniel R; Barrowdale, Daniel; Baynes, Caroline; Beckmann, Matthias W.; Benitez, Javier; Bermisheva, Marina; Bernstein, Leslie; Bignon, Yves Jean; Blazer, Kathleen R.; Blok, Marinus J.; Blomqvist, Carl; Blot, William; Bobolis, Kristie; Boeckx, Bram; Bogdanova, Natalia V.; Bojesen, Anders; Bojesen, Stig E.; Bonanni, Bernardo; Børresen-Dale, Anne-Lise; Bozsik, Aniko; Bradbury, Angela R; Brand, Judith S.; Brauch, Hiltrud; Brenner, Hermann; Bressac-de Paillerets, Brigitte; Brewer, Carole; Brinton, Louise; Broberg, Per; Brooks-Wilson, Angela R; Brunet, Joan; Brüning, Thomas; Burwinkel, Barbara; Buys, Saundra S.; Byun, Jinyoung; Cai, Qiuyin; Caldés, Trinidad; Caligo, Maria A.; Campbell, Ian; Canzian, Federico; Caron, Olivier; Carracedo, Angel; Carter, Brian D; Castelao, J Esteban; Castera, Laurent; Caux-Moncoutier, Virginie; Chan, Salina B; Chang-Claude, Jenny; Chanock, Stephen J.; Chen, Xiaoqing; Cheng, Ting-Yuan David; Chiquette, Jocelyne; Christiansen, Hans; Claes, Kathleen B M; Clarke, Christine L; Conner, Thomas; Conroy, Don M; Cook, Jackie; Cordina-Duverger, Emilie; Cornelissen, Sten; Coupier, Isabelle; Cox, Angela; Cox, David G.; Cross, Simon S.; Cuk, Katarina; Cunningham, Julie M; Czene, Kamila; Daly, Mary B.; Damiola, Francesca; Darabi, Hatef; Davidson, Rosemarie; De Leeneer, Kim; Devilee, Peter; Dicks, Ed; Diez, Orland; Ding, Yuan Chun; Ditsch, Nina; Doheny, Kimberly F; Domchek, Susan M.; Dorfling, Cecilia M.; Dörk, Thilo; Dos-Santos-Silva, Isabel; Dubois, Stéphane; Dugué, Pierre-Antoine; Dumont, Martine; Dunning, Alison M.; Durcan, Lorraine; Dwek, Miriam; Dworniczak, Bernd; Eccles, Diana; Eeles, Ros; Ehrencrona, Hans; Eilber, Ursula; Ejlertsen, Bent; Ekici, Arif B.; Eliassen, A. Heather; Engel, Christoph; Eriksson, Mikael; Fachal, Laura; Faivre, Laurence; Fasching, Peter A.; Faust, Ulrike; Figueroa, Jonine; Flesch-Janys, Dieter; Fletcher, Olivia; Flyger, Henrik; Foulkes, William D; Friedman, Eitan; Fritschi, Lin; Frost, Debra; Gabrielson, Marike; Gaddam, Pragna; Gammon, Marilie D.; Ganz, Patricia A; Gapstur, Susan M.; Garber, Judy; Garcia-Barberan, Vanesa; García-Sáenz, José A; Gaudet, Mia M.; Gauthier-Villars, Marion; Gehrig, Andrea; Georgoulias, Vassilios; Gerdes, Anne Marie; Giles, Graham G.; Glendon, Gord; Godwin, Andrew K.; Goldberg, Mark S.; Goldgar, David E.; González-Neira, Anna; Goodfellow, Paul; Greene, Mark H.; Alnæs, Grethe I Grenaker; Grip, Mervi; Gronwald, Jacek; Grundy, Anne; Gschwantler-Kaulich, Daphne; Guénel, Pascal; Guo, Qi; Haeberle, Lothar; Hahnen, Eric; Haiman, Christopher A.; Håkansson, Niclas; Hallberg, Emily; Hamann, Ute; Hamel, Nathalie; Hankinson, Susan; Hansen, Thomas V. O.; Harrington, Patricia; Hart, Steven N; Hartikainen, Jaana M.; Healey, Catherine S.; Hein, Alexander; Helbig, Sonja; Henderson, Alex; Heyworth, Jane S.; Hicks, Belynda; Hillemanns, Peter; Hodgson, Shirley V.; Hogervorst, Frans Bl; Hollestelle, Antoinette; Hooning, Maartje J.; Hoover, Bob; Hopper, John L.; Hu, Chunling; Huang, Guanmengqian; Hulick, Peter J; Humphreys, Keith; Hunter, David J.; Imyanitov, Evgeny N.; Isaacs, Claudine; Iwasaki, Motoki; Izatt, Louise; Jakubowska, Anna; James, Paul; Janavicius, Ramunas; Janni, Wolfgang; Jensen, Uffe Birk; John, Esther M.; Johnson, Nichola; Jones, Kristine; Jones, Michael; Jukkola-Vuorinen, Arja; Kaaks, Rudolf; Kabisch, Maria; Kaczmarek, Katarzyna; Kang, Daehee; Kast, Karin; Keeman, Renske; Kerin, Michael J.; Kets, Carolien M.; Keupers, Machteld; Khan, Sofia; Khusnutdinova, Elza; Kiiski, Johanna I; Kim, Sung-Won; Knight, Julia A.; Konstantopoulou, Irene; Kosma, Veli Matti; Kristensen, Vessela N.; Kruse, Torben A.; Kwong, Ava; Lænkholm, Anne-Vibeke; Laitman, Yael; Lalloo, Fiona; Lambrechts, Diether; Landsman, Keren; Lasset, Christine; Lazaro, Conxi; Le Marchand, Loic; Lecarpentier, Julie; Lee, Andrew; Lee, Eunjung; Lee, Jong Won; Lee, Min Hyuk; Lejbkowicz, Flavio; Lesueur, Fabienne; Li, Jingmei; Lilyquist, Jenna; Lincoln, Anne; Lindblom, Annika; Lissowska, Jolanta; So, Wing Yee; Loibl, Sibylle; Long, Jirong; Loud, Jennifer T; Lubinski, Jan; Luccarini, Craig; Lush, Michael J.; MacInnis, Robert J; Maishman, Tom; Makalic, Enes; Kostovska, Ivana Maleva; Malone, Kathleen E.; Manoukian, Siranoush; Manson, Joann E.; Margolin, Sara; Martens, John W. M.; Martinez, Maria Elena; Matsuo, Keitaro; Mavroudis, Dimitrios; Mazoyer, Sylvie; Mclean, Catriona; Meijers-Heijboer, Hanne; Menéndez, Primitiva; Meyer, Jeffery; Miao, Hui; Miller, Austin; Miller, Nicola; Mitchell, Gillian; Montagna, Marco; Muir, Kenneth; Mulligan, Anna Marie; Mulot, Claire; Nadesan, Sue; Nathanson, Katherine L.; Neuhausen, Susan L.; Nevanlinna, Heli; Nevelsteen, Ines; Niederacher, Dieter; Nielsen, Sune F.; Nordestgaard, Børge G.; Norman, Aaron; Nussbaum, Robert L.; Olah, Edith; Olopade, Olufunmilayo I.; Olson, Janet E.; Olswold, Curtis; Ong, Kai Ren; Oosterwijk, Jan C.; Orr, Nick; Osorio, Ana; Pankratz, V Shane; Papi, Laura; Park-Simon, Tjoung-Won; Paulsson-Karlsson, Ylva; Lloyd, Rachel; Pedersen, Inge Søkilde; Peissel, Bernard; Peixoto, Ana; Perez, Jose Ignacio Arias; Peterlongo, Paolo; Peto, Julian; Pfeiler, Georg; Phelan, Catherine M.; Pinchev, Mila; Plaseska-Karanfilska, Dijana; Poppe, Bruce; Porteous, Mary E.; Prentice, Ross L.; Presneau, Nadege; Prokofieva, Darya; Pugh, Elizabeth; Pujana, Miquel Angel; Pylkäs, Katri; Rack, Brigitte; Radice, Paolo; Rahman, Nazneen; Rantala, Johanna; Rappaport-Fuerhauser, Christine; Rennert, Gad; Rennert, Hedy S; Rhenius, Valerie; Rhiem, Kerstin; Richardson, Andrea; Rodriguez, Gustavo C.; Romero, Atocha; Romm, Jane; Rookus, Matti A.; Rudolph, Anja; Ruediger, Thomas; Saloustros, Emmanouil; Sanders, Joyce; Sandler, Dale P; Sangrajrang, Suleeporn; Sawyer, Elinor J.; Schmidt, Daniel F.; Schoemaker, Minouk J.; Schumacher, Fredrick; Schürmann, Peter; Schwentner, Lukas; Scott, Christopher; Scott, Rodney J; Seal, Sheila; Senter, Leigha; Seynaeve, Caroline; Shah, Mitul; Sharma, Priyanka; Shen, Chen Yang; Sheng, Xin; Shimelis, Hermela; Shrubsole, Martha J.; Shu, Xiao Ou; Side, Lucy E.; Singer, Christian F.; Sohn, Christof; Southey, Melissa C.; Spinelli, John J; Spurdle, Amanda B.; Stegmaier, Christa; Stoppa-Lyonnet, Dominique; Sukiennicki, Grzegorz; Surowy, Harald M.; Sutter, Christian; Swerdlow, Anthony J.; Szabo, Csilla I.; Tamimi, Rulla M; Tan, Yen; Taylor, Jack A; Tejada, Maria-Isabel; Tengström, Maria; Teo, Soo Hwang; Terry, Mary Beth; Tessier, Daniel C.; Teulé, Alex; Thöne, Kathrin; Thull, Darcy L; Tibiletti, Maria Grazia; Tihomirova, Laima; Tischkowitz, Marc; Toland, Amanda E.; Tollenaar, Rob A E M; Tomlinson, Ian; Tong, Ling; Torres, Diana; Tranchant, Martine; Truong, Thérèse; Tucker, Kathy; Tung, Nadine; Tyrer, Jonathan P.; Ulmer, Hans-Ulrich; Vachon, Celine; van Asperen, Christi J.; Van Den Berg, David; Van Den Ouweland, Ans M W; van Rensburg, Elizabeth J.; Varesco, Liliana; Varon-Mateeva, Raymonda; Vega, Ana; Viel, Alessandra; Vijai, Joseph; Vincent, Daniel; Vollenweider, Jason; Walker, Lisa; Wang, Zhaoming; Wang-Gohrke, Shan; Wappenschmidt, Barbara; Weinberg, Clarice R; Weitzel, Jeffrey N.; Wendt, Camilla; Wesseling, Jelle; Whittemore, Alice S.; Wijnen, Juul T.; Willett, Walter; Winqvist, Robert; Wolk, Alicja; Wu, Anna H.; Xia, Lucy; Yang, Xiaohong R.; Yannoukakos, Drakoulis; Zaffaroni, Daniela; Zheng, Wei; Zhu, B.; Ziogas, Argyrios; Ziv, Elad; Zorn, Kristin K; Gago-Dominguez, Manuela; Mannermaa, Arto; Olsson, Håkan; Teixeira, Manuel R.; Stone, Jennifer; Offit, Kenneth; Ottini, Laura; Park, Sue K.; Thomassen, Mads; Hall, Per; Meindl, Alfons; Schmutzler, Rita K.; Droit, Arnaud; Bader, Gary D.; Pharoah, Paul D. P.; Couch, Fergus J.; Easton, Douglas F.; Kraft, Peter; Chenevix-Trench, Georgia; García-Closas, Montserrat; Schmidt, Marjanka K.; Antoniou, Antonis C.; Simard, Jacques

    2017-01-01

    Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,414

  5. Identification of ten variants associated with risk of estrogen-receptor-negative breast cancer

    DEFF Research Database (Denmark)

    Milne, Roger L; Kuchenbaecker, Karoline B; Michailidou, Kyriaki

    2017-01-01

    Most common breast cancer susceptibility variants have been identified through genome-wide association studies (GWAS) of predominantly estrogen receptor (ER)-positive disease. We conducted a GWAS using 21,468 ER-negative cases and 100,594 controls combined with 18,908 BRCA1 mutation carriers (9,4...

  6. Estrogenic effects of fusarielins in human breast cancer cell lines

    DEFF Research Database (Denmark)

    Søndergaard, Teis; Klitgaard, Louise Graabæk; Purup, Stig

    2012-01-01

    without the estrogen receptor-α and MCF-10a cells without estrogen receptors were not stimulated by fusarielins. Furthermore, the stimulation was prevented in MCF-7 cells when fusarielins were incubated in the presence of the estrogen receptor antagonist fulvestrant. These observations suggest...

  7. Estrogens in breast cancer

    International Nuclear Information System (INIS)

    Terzieff, V.; Vázquez, A.

    2004-01-01

    The prolonged exposure to estrogen increases the risk of cancer breast, the precise role of estrogen in the carcinogenesis process is unclear. They are capable of inducing cell proliferation through different channels receptor Estrogen (ER) known, for example through MAPkinasa sensitivity the promoter of proliferation effect depends on the level of RE, or type to â, integrity (mutations may alter its function) and ligand. The different types of estrogens and related compounds have different profile of affinity for RE and effect end. The modulatory role of progestogens proliferation is very complex, and the interaction between the effector pathways of progestin’s, estrogens, EGF and IGF family - maybe others - determines the final effect .. Estrogens are mutagenic per se weak, but is now known for its hepatic metabolism occur highly reactive species such as quinones, and catechol, powerful mutagens in vitro. Direct or indirect genotoxicity probably explains Part of the effects of estrogen on tumor cells. The use of hormone replacement (HTR) increases the risk of CM, as proportional to the time of use. The combination with progestin seems to be increased risk (R R 2). It is unclear the role of phyto estrogens in the prevention the CM. In the male breast is known that the proliferative response to parenchymal different hormonal maneuvers is different. The effect is minimal castration are and maximum with the combination of estrogen and progesterone. It is unclear, however, the risk of the population exposed to hormone therapy for cancer prostate or otherwise

  8. Conditional expression of constitutively active estrogen receptor α in chondrocytes impairs longitudinal bone growth in mice

    International Nuclear Information System (INIS)

    Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko; Horie-Inoue, Kuniko; Inoue, Satoshi

    2012-01-01

    Highlights: ► Conditional transgenic mice expressing constitutively active estrogen receptor α (caERα) in chondrocytes were developed. ► Expression of caERα in chondrocytes impaired longitudinal bone growth in mice. ► caERα affects chondrocyte proliferation and differentiation. ► This mouse model is useful for understanding the physiological role of ERαin vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caERα ColII , expressing constitutively active mutant estrogen receptor (ER) α in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caERα ColII mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caERα ColII mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caERα ColII mice. These results suggest that ERα is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  9. Trichostatin A enhances estrogen receptor-alpha repression in MCF-7 breast cancer cells under hypoxia

    International Nuclear Information System (INIS)

    Noh, Hyunggyun; Park, Joonwoo; Shim, Myeongguk; Lee, YoungJoo

    2016-01-01

    Estrogen receptor (ER) is a crucial determinant of resistance to endocrine therapy, which may change during the progression of breast cancer. We previously showed that hypoxia induces ESR1 gene repression and ERα protein degradation via proteasome-mediated pathway in breast cancer cells. HDAC plays important roles in the regulation of histone and non-histone protein post-translational modification. HDAC inhibitors can induce epigenetic changes and have therapeutic potential for targeting various cancers. Trichostatin A exerts potent antitumor activities against breast cancer cells in vitro and in vivo. In this report, we show that TSA augments ESR1 gene repression at the transcriptional level and downregulates ERα protein expression under hypoxic conditions through a proteasome-mediated pathway. TSA-induced estrogen response element-driven reporter activity in the absence of estrogen was synergistically enhanced under hypoxia; however, TSA inhibited cell proliferation under both normoxia and hypoxia. Our data show that the hypoxia-induced repression of ESR1 and degradation of ERα are enhanced by concomitant treatment with TSA. These findings expand our understanding of hormone responsiveness in the tumor microenvironment; however, additional in-depth studies are required to elucidate the detailed mechanisms of TSA-induced ERα regulation under hypoxia. - Highlights: • TSA augments ESR1 gene repression at the transcriptional level under hypoxia. • TSA downregulates ERα protein expression under hypoxia. • TSA-induced ERα regulation under hypoxia is essential for understanding the behavior and progression of breast cancer.

  10. Trichostatin A enhances estrogen receptor-alpha repression in MCF-7 breast cancer cells under hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Hyunggyun; Park, Joonwoo; Shim, Myeongguk; Lee, YoungJoo, E-mail: yjlee@sejong.ac.kr

    2016-02-12

    Estrogen receptor (ER) is a crucial determinant of resistance to endocrine therapy, which may change during the progression of breast cancer. We previously showed that hypoxia induces ESR1 gene repression and ERα protein degradation via proteasome-mediated pathway in breast cancer cells. HDAC plays important roles in the regulation of histone and non-histone protein post-translational modification. HDAC inhibitors can induce epigenetic changes and have therapeutic potential for targeting various cancers. Trichostatin A exerts potent antitumor activities against breast cancer cells in vitro and in vivo. In this report, we show that TSA augments ESR1 gene repression at the transcriptional level and downregulates ERα protein expression under hypoxic conditions through a proteasome-mediated pathway. TSA-induced estrogen response element-driven reporter activity in the absence of estrogen was synergistically enhanced under hypoxia; however, TSA inhibited cell proliferation under both normoxia and hypoxia. Our data show that the hypoxia-induced repression of ESR1 and degradation of ERα are enhanced by concomitant treatment with TSA. These findings expand our understanding of hormone responsiveness in the tumor microenvironment; however, additional in-depth studies are required to elucidate the detailed mechanisms of TSA-induced ERα regulation under hypoxia. - Highlights: • TSA augments ESR1 gene repression at the transcriptional level under hypoxia. • TSA downregulates ERα protein expression under hypoxia. • TSA-induced ERα regulation under hypoxia is essential for understanding the behavior and progression of breast cancer.

  11. Activation of estrogen response elements is mediated both via estrogen and muscle contractions in rat skeletal muscle myotubes

    DEFF Research Database (Denmark)

    Wiik, A.; Hellsten, Ylva; Berthelson, P.

    2009-01-01

    is ER independent. The muscle contraction-induced transactivation of ERE and increase in ERbeta mRNA were instead found to be MAP kinase (MAPK) dependent. This study demonstrates for the first time that muscle contractions have a similar functional effect as estrogen in skeletal muscle myotubes, causing......The aim of the present study was to investigate the activation of estrogen response elements (EREs) by estrogen and muscle contractions in rat myotubes in culture and to assess whether the activation is dependent on the estrogen receptors (ERs). In addition, the effect of estrogen and contraction...... on the mRNA levels of ERalpha and ERbeta was studied to determine the functional consequence of the transactivation. Myoblasts were isolated from rat skeletal muscle and transfected with a vector consisting of sequences of EREs coupled to the gene for luciferase. The transfected myoblasts were...

  12. Association study of the estrogen receptor I gene (ESR1) in anorexia nervosa and eating disorders: No replication found

    NARCIS (Netherlands)

    Slof-Op 't Landt, M.C.T.; van Furth, E.F.; Meulenbelt, I.; Bartels, M.; Slagboom, P.E.; Boomsma, D.I.

    2014-01-01

    Objective The female preponderance and onset around puberty in the majority of eating disorders (EDs) suggest that sex hormones, like estrogens, may be involved in the onset of these disorders. An eight-SNP haplotype at the estrogen receptor I (ESR1) gene was found to be associated with anorexia

  13. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    International Nuclear Information System (INIS)

    Zhang, Yu; Cheng, Jung-Chien; Huang, He-Feng; Leung, Peter C.K.

    2013-01-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells

  14. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  15. Isoliquiritigenin exhibits anti-proliferative properties in the pituitary independent of estrogen receptor function

    International Nuclear Information System (INIS)

    Weis, Karen E.; Raetzman, Lori T.

    2016-01-01

    The plant flavonoid isoliquiritigenin (ISL) is a botanical estrogen widely taken as an herbal supplement to ease the symptoms of menopause. ISL has been also shown to have anti-tumor properties in a number of cancer cell backgrounds. However, the effects of ISL on normal cells are less well known and virtually unstudied in the context of the pituitary gland. We have established a pituitary explant culture model to screen chemical agents for gene expression changes within the pituitary gland during a period of active proliferation and differentiation. Using this whole-organ culture system we found ISL to be weakly estrogenic based on its ability to induce Cckar mRNA expression, an estrogen receptor (ER) mediated gene. Using a range of ISL from 200 nM to 200 μM, we discovered that ISL promoted cell proliferation at a low concentration, yet potently inhibited proliferation at the highest concentration. ICI 182,780 failed to antagonize ISL's repression of pituitary cell proliferation, indicating the effect is independent of ER signaling. Coincident with a decrease in proliferating cells, we observed down-regulation of transcript for cyclin D2 and E2 and a strong induction of mRNA and protein for the cyclin dependent kinase inhibitor Cdkn1a (p21). Importantly, high dose ISL did not alter the balance of progenitor vs. differentiated cell types within the pituitary explants and they seemed otherwise healthy; however, TUNEL staining revealed an increase in apoptotic cell death in ISL treated cultures. Our results merit further examination of ISL as an anti-tumor agent in the pituitary gland. - Highlights: • Isoliquiritigenin possesses weak estrogenic activity based on induction of Cckar. • ISL can be anti-proliferative in pituitary explants without altering cell lineages. • Anti-proliferative behavior of ISL is not estrogen receptor mediated. • ISL induces p21 expression leading to cell cycle arrest and apoptosis.

  16. Isoliquiritigenin exhibits anti-proliferative properties in the pituitary independent of estrogen receptor function

    Energy Technology Data Exchange (ETDEWEB)

    Weis, Karen E.; Raetzman, Lori T., E-mail: raetzman@life.illinois.edu

    2016-12-15

    The plant flavonoid isoliquiritigenin (ISL) is a botanical estrogen widely taken as an herbal supplement to ease the symptoms of menopause. ISL has been also shown to have anti-tumor properties in a number of cancer cell backgrounds. However, the effects of ISL on normal cells are less well known and virtually unstudied in the context of the pituitary gland. We have established a pituitary explant culture model to screen chemical agents for gene expression changes within the pituitary gland during a period of active proliferation and differentiation. Using this whole-organ culture system we found ISL to be weakly estrogenic based on its ability to induce Cckar mRNA expression, an estrogen receptor (ER) mediated gene. Using a range of ISL from 200 nM to 200 μM, we discovered that ISL promoted cell proliferation at a low concentration, yet potently inhibited proliferation at the highest concentration. ICI 182,780 failed to antagonize ISL's repression of pituitary cell proliferation, indicating the effect is independent of ER signaling. Coincident with a decrease in proliferating cells, we observed down-regulation of transcript for cyclin D2 and E2 and a strong induction of mRNA and protein for the cyclin dependent kinase inhibitor Cdkn1a (p21). Importantly, high dose ISL did not alter the balance of progenitor vs. differentiated cell types within the pituitary explants and they seemed otherwise healthy; however, TUNEL staining revealed an increase in apoptotic cell death in ISL treated cultures. Our results merit further examination of ISL as an anti-tumor agent in the pituitary gland. - Highlights: • Isoliquiritigenin possesses weak estrogenic activity based on induction of Cckar. • ISL can be anti-proliferative in pituitary explants without altering cell lineages. • Anti-proliferative behavior of ISL is not estrogen receptor mediated. • ISL induces p21 expression leading to cell cycle arrest and apoptosis.

  17. Breast cancer incidence by estrogen receptor status in Denmark from 1996 to 2007

    DEFF Research Database (Denmark)

    Bigaard, J; Stahlberg, C; Jensen, M-B

    2012-01-01

    During the past 50 years, breast cancer incidence has increased by 2-3 % annually. Despite many years of testing for estrogen receptors (ER), evidence is scarce on breast cancer incidence by ER status. The aim of this paper was to investigate the increase in breast cancer incidence by ER status...

  18. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    Science.gov (United States)

    In vitro screening assays designed to identify hormone mimics or antagonists, including those recommended for use in the EPA's Tier 1 screening battery, typically use mammalian estrogen (ER) and androgen receptors (AR) such as rat or human. Although we know that the amino acid s...

  19. Development of an image analysis screen for estrogen receptor alpha (ERα) ligands through measurement of nuclear translocation dynamics.

    Science.gov (United States)

    Dull, Angie; Goncharova, Ekaterina; Hager, Gordon; McMahon, James B

    2010-11-01

    We have developed a robust high-content assay to screen for novel estrogen receptor alpha (ERα) agonists and antagonists by quantitation of cytoplasmic to nuclear translocation of an estrogen receptor chimera in 384-well plates. The screen utilizes a green fluorescent protein tagged-glucocorticoid/estrogen receptor (GFP-GRER) chimera which consisted of the N-terminus of the glucocorticoid receptor fused to the human ER ligand binding domain. The GFP-GRER exhibited cytoplasmic localization in the absence of ERα ligands, and translocated to the nucleus in response to stimulation with ERα agonists or antagonists. The BD Pathway 435 imaging system was used for image acquisition, analysis of translocation dynamics, and cytotoxicity measurements. The assay was validated with known ERα agonists and antagonists, and the Library of Pharmacologically Active Compounds (LOPAC 1280). Additionally, screening of crude natural product extracts demonstrated the robustness of the assay, and the ability to quantitate the effects of toxicity on nuclear translocation dynamics. The GFP-GRER nuclear translocation assay was very robust, with z' values >0.7, CVs screening of natural product extracts. This assay has been developed for future primary screening of synthetic, pure natural products, and natural product extracts libraries available at the National Cancer Institute at Frederick. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Location analysis for the estrogen receptor-? reveals binding to diverse ERE sequences and widespread binding within repetitive DNA elements

    OpenAIRE

    Mason, Christopher E.; Shu, Feng-Jue; Wang, Cheng; Session, Ryan M.; Kallen, Roland G.; Sidell, Neil; Yu, Tianwei; Liu, Mei Hui; Cheung, Edwin; Kallen, Caleb B.

    2010-01-01

    Location analysis for estrogen receptor-? (ER?)-bound cis-regulatory elements was determined in MCF7 cells using chromatin immunoprecipitation (ChIP)-on-chip. Here, we present the estrogen response element (ERE) sequences that were identified at ER?-bound loci and quantify the incidence of ERE sequences under two stringencies of detection:

  1. Seasonal Relationship between Gonadotropin, Growth Hormone, and Estrogen Receptor mRNA Expression in the Pituitary Gland of Largemouth Bass

    OpenAIRE

    Martyniuk, Christopher J; Kroll, Kevin J.; Porak, Wesley F.; Steward, Cheree; Grier, Harry J.; Denslow, Nancy D.

    2009-01-01

    The objectives of this study were to investigate the seasonal changes in pituitary gonadotropins, growth hormone (GH), and estrogen receptor (ER) isoform mRNA in wild female and male largemouth bass (LMB) (Micropterus salmoides) from an unpolluted habitat to better understand reproductive physiology in this ecologically important species. Female pituitary luteinizing hormone (LH) β subunit and follicle-stimulating hormone (FSH) β subunit mRNA showed significant seasonal variation with levels ...

  2. Repression of estrogen receptor β function by putative tumor suppressor DBC1

    International Nuclear Information System (INIS)

    Koyama, Satoshi; Wada-Hiraike, Osamu; Nakagawa, Shunsuke; Tanikawa, Michihiro; Hiraike, Haruko; Miyamoto, Yuichiro; Sone, Kenbun; Oda, Katsutoshi; Fukuhara, Hiroshi; Nakagawa, Keiichi; Kato, Shigeaki; Yano, Tetsu; Taketani, Yuji

    2010-01-01

    It has been well established that estrogen is involved in the pathophysiology of breast cancer. Estrogen receptor (ER) α appears to promote the proliferation of cancer tissues, while ERβ can protect against the mitogenic effect of estrogen in breast tissue. The expression status of ERα and ERβ may greatly influence on the development, treatment, and prognosis of breast cancer. Previous studies have indicated that the deleted in breast cancer 1 (DBC1/KIAA1967) gene product has roles in regulating functions of nuclear receptors. The gene encoding DBC1 is a candidate for tumor suppressor identified by genetic search for breast cancer. Caspase-dependent processing of DBC1 promotes apoptosis, and depletion of the endogenous DBC1 negatively regulates p53-dependent apoptosis through its specific inhibition of SIRT1. In addition, DBC1 modulates ERα expression and promotes breast cancer cell survival by binding to ERα. Here we report an ERβ-specific repressive function of DBC1. Immunoprecipitation and immunofluorescence studies show that ERβ and DBC1 interact in a ligand-independent manner similar to ERα. In vitro pull-down assays revealed a direct interaction between DBC1 amino-terminus and activation function-1/2 domain of ERβ. Although DBC1 shows no influence on the ligand-dependent transcriptional activation function of ERα, the expression of DBC1 negatively regulates the ligand-dependent transcriptional activation function of ERβin vivo, and RNA interference-mediated depletion of DBC1 stimulates the transactivation function of ERβ. These results implicate the principal role of DBC1 in regulating ERβ-dependent gene expressions.

  3. Aryl hydrocarbon receptor (AhR) inducers and estrogen receptor (ER) activities in surface sediments of Three Gorges Reservoir, China evaluated with in vitro cell bioassays

    NARCIS (Netherlands)

    Wang, J.; Bovee, T.F.H.; Bi, Y.; Bernhöft, S.; Schramm, K.W.

    2014-01-01

    Two types of biological tests were employed for monitoring the toxicological profile of sediment cores in the Three Gorges Reservoir (TGR), China. In the present study, sediments collected in June 2010 from TGR were analyzed for estrogen receptor (ER)- and aryl hydrocarbon receptor (AhR)-mediated

  4. Interactions between estrogen receptors and metabotropic glutamate receptors and their impact on drug addiction in females.

    Science.gov (United States)

    Tonn Eisinger, Katherine R; Gross, Kellie S; Head, Brian P; Mermelstein, Paul G

    2018-03-10

    Estrogen receptors α and β (ERα and ERβ) have a unique relationship with metabotropic glutamate receptors (mGluRs) in the female rodent brain such that estradiol is able to recruit intracellular G-protein signaling cascades to influence neuronal physiology, structure, and ultimately behavior. While this association between ERs and mGluRs exists in many cell types and brain regions, its effects are perhaps most striking in the nucleus accumbens (NAc). This review will discuss the original characterization of ER/mGluR signaling and how estradiol activity in the NAc confers increased sensitivity to drugs of abuse in females through this mechanism. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Do Soy Isoflavones Provide Protection Against Prostate Cancer Via a Classical Estrogen Receptor-Alpha (Era) Independent Mechanism?

    National Research Council Canada - National Science Library

    Lubahn, Dennis

    2001-01-01

    .... Our hypothesis is that soy isoflavones, specifically genistein and daidzein, will provide protection from development and progression of prostate cancer in mice lacking functional estrogen receptor...

  6. Tamoxifen and ICI 182,780 activate hypothalamic G protein-coupled estrogen receptor 1 to rapidly facilitate lordosis in female rats.

    Science.gov (United States)

    Long, Nathan; Long, Bertha; Mana, Asma; Le, Dream; Nguyen, Lam; Chokr, Sima; Sinchak, Kevin

    2017-03-01

    In the female rat, sexual receptivity (lordosis) can be facilitated by sequential activation of estrogen receptor (ER) α and G protein-coupled estrogen receptor 1 (GPER) by estradiol. In the estradiol benzoate (EB) primed ovariectomized (OVX) rat, EB initially binds to ERα in the plasma membrane that complexes with and transactivates metabotropic glutamate receptor 1a to activate β-endorphin neurons in the arcuate nucleus of the hypothalamus (ARH) that project to the medial preoptic nucleus (MPN). This activates MPN μ-opioid receptors (MOP), inhibiting lordosis. Infusion of non-esterified 17β-estradiol into the ARH rapidly reduces MPN MOP activation and facilitates lordosis via GPER. Tamoxifen (TAM) and ICI 182,780 (ICI) are selective estrogen receptor modulators that activate GPER. Therefore, we tested the hypothesis that TAM and ICI rapidly facilitate lordosis via activation of GPER in the ARH. Our first experiment demonstrated that injection of TAM intraperitoneal, or ICI into the lateral ventricle, deactivated MPN MOP and facilitated lordosis in EB-primed rats. We then tested whether TAM and ICI were acting rapidly through a GPER dependent pathway in the ARH. In EB-primed rats, ARH infusion of either TAM or ICI facilitated lordosis and reduced MPN MOP activation within 30min compared to controls. These effects were blocked by pretreatment with the GPER antagonist, G15. Our findings demonstrate that TAM and ICI deactivate MPN MOP and facilitate lordosis in a GPER dependent manner. Thus, TAM and ICI may activate GPER in the CNS to produce estrogenic actions in neural circuits that modulate physiology and behavior. Published by Elsevier Inc.

  7. Rainbow trout estrogen receptor (ER) competitive bindng and vitellogenin induction agonism/antagonism data for 94 chemicals

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset is from screening 94 diverse chemicals for estrogen receptor (ER) activation in a competitive rainbow trout ER binding assay and a trout liver slice...

  8. Human glutathione S-transferase P1-1 functions as an estrogen receptor α signaling modulator

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiyuan [Department of Biological Science, Sookmyung Women’s University, Seoul (Korea, Republic of); An, Byoung Ha [Department of Food and Nutrition, College of Life Science, Sookmyung Women’s University, Seoul (Korea, Republic of); Kim, Min Jung; Park, Jong Hoon [Department of Biological Science, Sookmyung Women’s University, Seoul (Korea, Republic of); Kang, Young Sook [Department of Pharmacy, College of Pharmacy, Sookmyung Women’s University, Seoul (Korea, Republic of); Chang, Minsun, E-mail: minsunchang@sm.ac.kr [Department of Medical and Pharmaceutical Science, College of Science, Sookmyung Women’s University, Seoul (Korea, Republic of)

    2014-09-26

    Highlights: • GSTP induces the classical ERα signaling event. • The functional GSTP is a prerequisite for GSTP-induced ERα transcription activity. • The expression of RIP140, a transcription cofactor, was inhibited by GSTP protein. • We propose the novel non-enzymatic role of GSTP. - Abstract: Estrogen receptor α (ERα) plays a crucial role in estrogen-mediated signaling pathways and exerts its action as a nuclear transcription factor. Binding of the ligand-activated ERα to the estrogen response element (ERE) is a central part of ERα-associated signal transduction pathways and its aberrant modulation is associated with many disease conditions. Human glutathione S-transferase P1-1 (GSTP) functions as an enzyme in conjugation reactions in drug metabolism and as a regulator of kinase signaling pathways. It is overexpressed in tumors following chemotherapy and has been associated with a poor prognosis in breast cancer. In this study, a novel regulatory function of GSTP has been proposed in which GSTP modulates ERE-mediated ERα signaling events. Ectopic expression of GSTP was able to induce the ERα and ERE-mediated transcriptional activities in ERα-positive but GSTP-negative MCF7 human breast cancer cells. This inductive effect of GSTP on the ERE-transcription activity was diminished when the cells express a mutated form of the enzyme or are treated with a GSTP-specific chemical inhibitor. It was found that GSTP inhibited the expression of the receptor interacting protein 140 (RIP140), a negative regulator of ERα transcription, at both mRNA and protein levels. Our study suggests a novel non-enzymatic role of GSTP which plays a significant role in regulating the classical ERα signaling pathways via modification of transcription cofactors such as RIP140.

  9. Estrogenic compounds decrease growth hormone receptor abundance and alter osmoregulation in Atlantic salmon

    Science.gov (United States)

    Lerner, Darren T.; Sheridan, Mark A.; McCormick, Stephen D.

    2012-01-01

    Exposure of Atlantic salmon smolts to estrogenic compounds is shown to compromise several aspects of smolt development. We sought to determine the underlying endocrine mechanisms of estrogen impacts on the growth hormone (GH)/insulin-like growth factor I (IGF-I) axis. Smolts in freshwater (FW) were either injected 3 times over 10 days with 2 μg g−1 17β-estradiol (E2) or 150 μg g−1 4-nonylphenol (NP). Seawater (SW)-acclimated fish received intraperitoneal implants of 30 μg g−1 E2 over two weeks. Treatment with these estrogenic compounds increased hepatosomatic index and total plasma calcium. E2 and NP reduced maximum growth hormone binding by 30–60% in hepatic and branchial membranes in FW and SW, but did not alter the dissociation constant. E2 and NP treatment decreased plasma levels of IGF-I levels in both FW and SW. In FW E2 and NP decreased plasma GH whereas in SW plasma GH increased after E2 treatment. Compared to controls, plasma chloride concentrations of E2-treated fish were decreased 5.5 mM in FW and increased 10.5 mM in SW. There was no effect of NP or E2 on gill sodium–potassium adenosine triphosphatase (Na+/K+-ATPase) activity in FW smolts, whereas E2 treatment in SW reduced gill Na+/K+-ATPase activity and altered the number and size of ionocytes. Our data indicate that E2 downregulates the GH/IGF-I-axis and SW tolerance which may be part of its normal function for reproduction and movement into FW. We conclude that the mechanism of endocrine disruption of smolt development by NP is in part through alteration of the GH/IGF-I axis via reduced GH receptor abundance.

  10. Estrogen receptor accessory proteins augment receptor-DNA interaction and DNA bending.

    Science.gov (United States)

    Landel, C C; Potthoff, S J; Nardulli, A M; Kushner, P J; Greene, G L

    1997-01-01

    Increasing evidence suggests that accessory proteins play an important role in the ability of the estrogen receptor (ER) and other nuclear hormone receptors to modulate transcription when bound to cis-acting hormone response elements in target genes. We have previously shown that four proteins, hsp70, protein disulfide isomerase (PDI) and two unknown proteins (p48 and p45), copurify with ER that has been isolated by site-specific DNA chromatography (BERE) and influence the interaction of ER with DNA in vitro. To better define the nature of these effects, we used filter binding and electrophoretic mobility shift assays to study the ability of these proteins to alter the kinetics of ER-DNA interaction and to influence the ability of ER to bend DNA when bound to an estrogen response element (ERE). The results of both assays indicate that ERE-purified ER, with its four associated proteins (hsp70, PDI, p48, p45), has a greater ability to bind to the vitellogenin A2 ERE than ER purified by estradiol-Sepharose chromatography in the absence (ESeph) or presence (EATP) of ATP, in which p48, p45 (ESeph) and hsp70 (EATP) are removed. Surprisingly, the rates of association and dissociation of ER and ERE were essentially the same for all three mixtures, suggesting that one or more ER-associated proteins, especially p45 and p48, may be required for ER to attain maximum DNA binding activity. In addition, circular permutation and phasing analyses demonstrated that the same ER-associated proteins produced higher order ER-DNA complexes that significantly increased the magnitude of DNA distortion, but did not alter the direction of the ER-induced bend of ERE-containing DNA fragments, which was toward the major groove of the DNA helix. These results suggest that p45 and/or p48 and possibly hsp70, play an important role both in the specific DNA binding and bending activities of ER and thus contribute to the overall stimulation of transcription in target genes that contain cis

  11. Estrogenic mediation of serotonergic and neurotrophic systems: implications for female mood disorders.

    Science.gov (United States)

    Borrow, Amanda P; Cameron, Nicole M

    2014-10-03

    Clinical research has demonstrated a significant sex difference in the occurrence of depressive disorders. Beginning at pubertal onset, women report a higher incidence of depression than men. Women are also vulnerable to the development of depressive disorders such as premenstrual dysphoric disorder, postpartum depression, and perimenopausal depression. These disorders are associated with reproductive stages involving changes in gonadal hormone levels. Specifically, female depression and female affective behaviors are influenced by estradiol levels. This review argues two major mechanisms by which estrogens influence depression and depressive-like behavior: through interactions with neurotrophic factors and through an influence on the serotonergic system. In particular, estradiol increases brain derived neurotrophic factor (BDNF) levels within the brain, and alters serotonergic expression in a receptor subtype-specific manner. We will take a regional approach, examining these effects of estrogens in the major brain areas implicated in depression. Finally, we will discuss the gaps in our current knowledge of the effects of estrogens on female depression, and the potential utility for estrogen receptor modulators in treatment for this disorder. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Association Between a Germline OCA2 Polymorphism at Chromosome 15q13.1 and Estrogen Receptor-Negative Breast Cancer Survival

    DEFF Research Database (Denmark)

    Azzato, E.M.; Tyrer, J.; Fasching, P.A.

    2010-01-01

    -sided. In the hypothesis-generating dataset, SNP rs4778137 (C > G) of the OCA2 gene at 15q13.1 was statistically significantly associated with overall survival among patients with estrogen receptor-negative tumors, with the rare G allele being associated with increased overall survival (HR of death per rare allele carried.......92, P = 5 x 10(-4)). The rare G allele of the OCA2 polymorphism, rs4778137, may be associated with improved overall survival among patients with estrogen receptor-negative breast cancer...

  13. An estrogen-associated dietary pattern and breast cancer risk in the Swedish Mammography Cohort.

    Science.gov (United States)

    Harris, Holly R; Bergkvist, Leif; Wolk, Alicja

    2015-11-01

    High endogenous hormone levels have been associated with breast cancer and dietary factors have the potential to influence breast cancer risk through effects on hormone levels. Dietary patterns derived from reduced rank regression provide a way to identify food groups correlated with hormones and subsequently examine food patterns that may be associated with breast cancer risk. We investigated whether a dietary pattern previously correlated with estradiol and estrone sulfate was associated with breast cancer in the prospective Swedish Mammography Cohort. Among 37,004 primarily postmenopausal women diet was assessed with a food frequency questionnaire. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs). During 15 years of follow-up 1,603 cases of breast cancer were identified. A higher estrogen dietary pattern score was associated with an increased risk of breast cancer. Women in the highest quartile of estrogen pattern score had a 29% (95% CI = 1.08-1.55) increased risk of breast cancer compared to women in the lowest quartile (p(trend) = 0.006). When the association was examined by estrogen-receptor status, it was only significant for those with estrogen-receptor-positive tumors; however, in the competing risk analysis there were no significant differences in the effect estimates by receptor subtype (p(heterogeneity) = 0.65). Our findings suggest that a dietary pattern associated with higher estrogen levels may increase breast cancer risk. However, whether the influence of this dietary pattern is through a direct effect on estrogen levels deserves further study. © 2015 UICC.

  14. Interaction of polymorphisms in the genes encoding interleukin-6 and estrogen receptor beta on the susceptibility to Parkinson's disease.

    Science.gov (United States)

    Håkansson, Anna; Westberg, Lars; Nilsson, Staffan; Buervenich, Silvia; Carmine, Andrea; Holmberg, Björn; Sydow, Olof; Olson, Lars; Johnels, Bo; Eriksson, Elias; Nissbrandt, Hans

    2005-02-05

    The multifunctional cytokine interleukin-6 (IL-6) is involved in inflammatory processes in the central nervous system and increased levels of IL-6 have been found in patients with Parkinson's disease (PD). It is known that estrogen inhibits the production of IL-6, via action on estrogen receptors, thereby pointing to an important influence of estrogen on IL-6. In a previous study, we reported an association between a G/A single nucleotide polymorphism (SNP) at position 1730 in the gene coding for estrogen receptor beta (ERbeta) and age of onset of PD. To investigate the influence of a G/C SNP at position 174 in the promoter of the IL-6 gene, and the possible interaction of this SNP and the ERbeta G-1730A SNP on the risk for PD, the G-174C SNP was genotyped, by pyrosequencing, in 258 patients with PD and 308 controls. A significantly elevated frequency of the GG genotype of the IL-6 SNP was found in the patient group and this was most obvious among patients with an early age of onset (

  15. Perturbation of estrogen receptor α localization with synthetic nona-arginine LXXLL-peptide coactivator binding inhibitors

    NARCIS (Netherlands)

    Carraz, M.; Zwart, W.; Phan, T.; Michalides, R.; Brunsveld, L.

    2009-01-01

    The interaction of estrogen receptor a (ERa) with the consensus LXXLL motifs of transcriptional coactivators provides an entry for functional ERa inhibition. Here, synthetic cell-permeable LXXLL peptide probes are brought forward that allow evaluation of the interaction of specific recognition

  16. BA321, a novel carborane analog that binds to androgen and estrogen receptors, acts as a new selective androgen receptor modulator of bone in male mice

    International Nuclear Information System (INIS)

    Watanabe, Kenta; Hirata, Michiko; Tominari, Tsukasa; Matsumoto, Chiho; Endo, Yasuyuki; Murphy, Gillian; Nagase, Hideaki

    2016-01-01

    Carboranes are a class of carbon-containing polyhedral boron cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors such as estrogen receptor (ER) and androgen receptor (AR). We have synthesized BA321, a novel carborane compound, which binds to AR. We found here that it also binds to ERs, ERα and ERβ. In orchidectomized (ORX) mice, femoral bone mass was markedly reduced due to androgen deficiency and BA321 restored bone loss in the male, whilst the decreased weight of seminal vesicle in ORX mice was not recovered by administration of BA321. In female mice, BA321 acts as a pure estrogen agonist, and restored both the loss of bone mass and uterine atrophy due to estrogen deficiency in ovariectomized (OVX) mice. In bone tissues, the trabecular bone loss occurred in both ORX and OVX mice, and BA321 completely restored the trabecular bone loss in both sexes. Cortical bone loss occurred in ORX mice but not in OVX mice, and BA321 clearly restored cortical bone loss due to androgen deficiency in ORX mice. Therefore, BA321 is a novel selective androgen receptor modulator (SARM) that may offer a new therapy option for osteoporosis in the male. - Highlights: • A novel carborane compound BA321 binds to both AR and ERs, ERα and ERβ. • BA321 restores bone loss in orchidectomized mice without effects on sex organ. • BA321 acts as an estrogen agonist in bone and uterus in ovariectomized mice. • BA321 may be a new SARM to prevent the loss of musculoskeletal mass in elder men.

  17. BA321, a novel carborane analog that binds to androgen and estrogen receptors, acts as a new selective androgen receptor modulator of bone in male mice

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Kenta [Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Cooperative Major in Advanced Health Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Hirata, Michiko [Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Tominari, Tsukasa [Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Matsumoto, Chiho [Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Endo, Yasuyuki [Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, 4-4-1, Komatsushima, Aoba-ku, Sendai, 981-8558 (Japan); Murphy, Gillian [Department of Oncology, University of Cambridge, Cancer Research UK, Cambridge Institute, Li Ka Shing Centre, Cambridge, CB2 0RE (United Kingdom); Nagase, Hideaki [Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588 (Japan); Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, OX3 7FY (United Kingdom); and others

    2016-09-09

    Carboranes are a class of carbon-containing polyhedral boron cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors such as estrogen receptor (ER) and androgen receptor (AR). We have synthesized BA321, a novel carborane compound, which binds to AR. We found here that it also binds to ERs, ERα and ERβ. In orchidectomized (ORX) mice, femoral bone mass was markedly reduced due to androgen deficiency and BA321 restored bone loss in the male, whilst the decreased weight of seminal vesicle in ORX mice was not recovered by administration of BA321. In female mice, BA321 acts as a pure estrogen agonist, and restored both the loss of bone mass and uterine atrophy due to estrogen deficiency in ovariectomized (OVX) mice. In bone tissues, the trabecular bone loss occurred in both ORX and OVX mice, and BA321 completely restored the trabecular bone loss in both sexes. Cortical bone loss occurred in ORX mice but not in OVX mice, and BA321 clearly restored cortical bone loss due to androgen deficiency in ORX mice. Therefore, BA321 is a novel selective androgen receptor modulator (SARM) that may offer a new therapy option for osteoporosis in the male. - Highlights: • A novel carborane compound BA321 binds to both AR and ERs, ERα and ERβ. • BA321 restores bone loss in orchidectomized mice without effects on sex organ. • BA321 acts as an estrogen agonist in bone and uterus in ovariectomized mice. • BA321 may be a new SARM to prevent the loss of musculoskeletal mass in elder men.

  18. Estrogen signalling and the DNA damage response in hormone dependent breast cancers

    Directory of Open Access Journals (Sweden)

    C Elizabeth Caldon

    2014-05-01

    Full Text Available Estrogen is necessary for the normal growth and development of breast tissue, but high levels of estrogen are a major risk factor for breast cancer. One mechanism by which estrogen could contribute to breast cancer is via the induction of DNA damage. This perspective discusses the mechanisms by which estrogen alters the DNA damage response (DDR and DNA repair through the regulation of key effector proteins including ATM, ATR, CHK1, BRCA1 and p53 and the feedback on estrogen receptor signalling from these proteins. We put forward the hypothesis that estrogen receptor signalling converges to suppress effective DNA repair and apoptosis in favour of proliferation. This is important in hormone-dependent breast cancer as it will affect processing of estrogen-induced DNA damage, as well as other genotoxic insults. DDR and DNA repair proteins are frequently mutated or altered in estrogen responsive breast cancer which will further change the processing of DNA damage. Finally the action of estrogen signalling on DNA damage is also relevant to the therapeutic setting as the suppression of a DNA damage response by estrogen has the potential to alter the response of cancers to anti-hormone treatment or chemotherapy that induces DNA damage.

  19. Epigenetics of Estrogen Receptor Signaling: Role in Hormonal Cancer Progression and Therapy

    International Nuclear Information System (INIS)

    Mann, Monica; Cortez, Valerie; Vadlamudi, Ratna K.

    2011-01-01

    Estrogen receptor (ERα) signaling plays a key role in hormonal cancer progression. ERα is a ligand-dependent transcription factor that modulates gene transcription via recruitment to the target gene chromatin. Emerging evidence suggests that ERα signaling has the potential to contribute to epigenetic changes. Estrogen stimulation is shown to induce several histone modifications at the ERα target gene promoters including acetylation, phosphorylation and methylation via dynamic interactions with histone modifying enzymes. Deregulation of enzymes involved in the ERα -mediated epigenetic pathway could play a vital role in ERα driven neoplastic processes. Unlike genetic alterations, epigenetic changes are reversible, and hence offer novel therapeutic opportunities to reverse ERα driven epigenetic changes. In this review, we summarize current knowledge on mechanisms by which ERα signaling potentiates epigenetic changes in cancer cells via histone modifications

  20. Epigenetics of Estrogen Receptor Signaling: Role in Hormonal Cancer Progression and Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Monica; Cortez, Valerie [Department of Cellular and Structural Biology, UTHSCSA, 7703 Floyd Curl Drive, San Antonio, TX 78229 (United States); Vadlamudi, Ratna K., E-mail: vadlamudi@uthscsa.edu [Department of Obstetrics and Gynecology, UTHSCSA, 7703 Floyd Curl Drive, San Antonio, TX 78229 (United States)

    2011-03-29

    Estrogen receptor (ERα) signaling plays a key role in hormonal cancer progression. ERα is a ligand-dependent transcription factor that modulates gene transcription via recruitment to the target gene chromatin. Emerging evidence suggests that ERα signaling has the potential to contribute to epigenetic changes. Estrogen stimulation is shown to induce several histone modifications at the ERα target gene promoters including acetylation, phosphorylation and methylation via dynamic interactions with histone modifying enzymes. Deregulation of enzymes involved in the ERα -mediated epigenetic pathway could play a vital role in ERα driven neoplastic processes. Unlike genetic alterations, epigenetic changes are reversible, and hence offer novel therapeutic opportunities to reverse ERα driven epigenetic changes. In this review, we summarize current knowledge on mechanisms by which ERα signaling potentiates epigenetic changes in cancer cells via histone modifications.

  1. Effect of highly bioaccumulated polychlorinated biphenyl congeners on estrogen and androgen receptor activity

    DEFF Research Database (Denmark)

    Bonefeld-Jørgensen, E.C.; Andersen, H. R.; Rasmussen, T.H.

    2001-01-01

    pleiotropic effects on the estrogen- and androgen-receptor. In MCF-7 cells a slightly increased cell proliferation was observed at low concentrations (1-10 nM) in cells co-treated with 0.01 nM 17 beta -Estradiol. whereas the compounds inhibited cell growth significantly at 1 and 10 muM. In reporter gene (ERE-tk-CAT...

  2. Decreased alternative splicing of estrogen receptor-α mRNA in the Alzheimer's disease brain

    NARCIS (Netherlands)

    Ishunina, Tatjana A.; Swaab, Dick F.

    2012-01-01

    In this study we identified 62 estrogen receptor alpha (ERα) mRNA splice variants in different human brain areas of Alzheimer's disease (AD) and control cases and classified them into 12 groups. Forty-eight of these splice forms were identified for the first time. The distribution of alternatively

  3. Neonatal paternal deprivation impairs social recognition and alters levels of oxytocin and estrogen receptor α mRNA expression in the MeA and NAcc, and serum oxytocin in mandarin voles.

    Science.gov (United States)

    Cao, Yan; Wu, Ruiyong; Tai, Fadao; Zhang, Xia; Yu, Peng; An, Xiaolei; Qiao, Xufeng; Hao, Ping

    2014-01-01

    Paternal care is necessary for the healthy development of social behavior in monogamous rodents and social recognition underpins social behavior in these animals. The effects of paternal care on the development of social recognition and underlying neuroendocrine mechanisms, especially the involvement of oxytocin and estrogen pathways, remain poorly understood. We investigated the effects of paternal deprivation (PD: father was removed from neonatal pups and mother alone raised the offspring) on social recognition in mandarin voles (Microtus mandarinus), a socially monogamous rodent. Paternal deprivation was found to inhibit the development of social recognition in female and male offspring according to a habituation-dishabituation paradigm. Paternal deprivation resulted in increased inactivity and reduced investigation during new encounters with other animals. Paternal deprivation reduced oxytocin receptor (OTR) and estrogen receptor α (ERα) mRNA expression in the medial amygdala and nucleus accumbens. Paternal deprivation reduced serum oxytocin (OT) concentration in females, but had no effect on males. Our results provide substantial evidence that paternal deprivation inhibits the development of social recognition in female and male mandarin voles and alters social behavior later in life. This is possibly the result of altered expression of central OTR and ERα and serum OT levels caused by paternal deprivation. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Suppression of elevated cartilage turnover in postmenopausal women and in ovariectomized rats by estrogen and a selective estrogen-receptor modulator (SERM).

    Science.gov (United States)

    Christgau, Stephan; Tankó, László B; Cloos, Paul A C; Mouritzen, Ulrik; Christiansen, Claus; Delaissé, Jean-Marie; Høegh-Andersen, Pernille

    2004-01-01

    Several observational studies indicate that estrogen deficiency increases the incidence of osteoarthritis in postmenopausal women. To validate this observation, we investigated the effects of ovariectomy (OVX) on cartilage erosion in rats using histology and an established bio-assay of cartilage-specific collagen type II degradation products (CTX-II). Furthermore, we investigated whether estrogen and levormeloxifene, a selective estrogen-receptor modulator (SERM), can prevent the OVX-induced changes in cartilage degradation. The clinical relevance was assessed in postmenopausal women by measuring the changes in CTX-II during 12-month treatment with levormeloxifene versus placebo. Sixty 6-month-old rats were divided in five groups. One group was subjected to sham and the others to OVX, followed by treatment with vehicle alone, estradiol or 0.2 mg/kg/day or 5 mg/kg/day of levormeloxifene. The rats were treated for 9 weeks with biweekly blood and urine sampling for measurement of bone resorption and cartilage turnover. After study termination, hind knees were removed for histological analysis of erosions. The effect of levormeloxifene in post-menopausal women was assessed by measuring CTX-II in samples from 301 women who were participating in a phase II study of this SERM. OVX rats showed significant increases in the urinary excretion of CTX-II. After 9 weeks this was manifested as increased surface erosion of knee articular cartilage compared with sham-operated rats. Treatment with estrogen or levormeloxifene prevented the OVX-induced changes. There was a significant correlation between the 4-week changes in CTX-II and cartilage erosion at week 9 (r = 0.64, P women treated with levormeloxifene, the urinary excretion of CTX-II was decreased by approximately 50% and restored CTX-II levels to the premenopausal range. This study is the first to demonstrate that a SERM suppresses cartilage degradation in both rodents and humans, suggesting potential therapeutical benefits

  5. Estrogen alters the diurnal rhythm of alpha 1-adrenergic receptor densities in selected brain regions

    International Nuclear Information System (INIS)

    Weiland, N.G.; Wise, P.M.

    1987-01-01

    Norepinephrine regulates the proestrous and estradiol-induced LH surge by binding to alpha 1-adrenergic receptors. The density of alpha 1-receptors may be regulated by estradiol, photoperiod, and noradrenergic neuronal activity. We wished to determine whether alpha 1-receptors exhibit a diurnal rhythm in ovariectomized and/or estradiol-treated female rats, whether estradiol regulates alpha 1-receptors in those areas of brain involved with LH secretion and/or sexual behavior, and whether the concentrations of alpha-receptors vary inversely relative to previously reported norepinephrine turnover patterns. Young female rats, maintained on a 14:10 light-dark cycle were ovariectomized. One week later, half of them were outfitted sc with Silastic capsules containing estradiol. Groups of animals were decapitated 2 days later at 0300, 1000, 1300, 1500, 1800, and 2300 h. Brains were removed, frozen, and sectioned at 20 micron. Sections were incubated with [ 3 H]prazosin in Tris-HCl buffer, washed, dried, and exposed to LKB Ultrofilm. The densities of alpha 1-receptors were quantitated using a computerized image analysis system. In ovariectomized rats, the density of alpha 1-receptors exhibited a diurnal rhythm in the suprachiasmatic nucleus (SCN), medial preoptic nucleus (MPN), and pineal gland. In SCN and MPN, receptor concentrations were lowest during the middle of the day and rose to peak levels at 1800 h. In the pineal gland, the density of alpha 1-receptors was lowest at middark phase, rose to peak levels before lights on, and remained elevated during the day. Estradiol suppressed the density of alpha 1 binding sites in the SCN, MPN, median eminence, ventromedial nucleus, and the pineal gland but had no effect on the lateral septum. Estrogen treatment altered the rhythm of receptor densities in MPN, median eminence, and the pineal gland

  6. Estrogen alters the diurnal rhythm of alpha 1-adrenergic receptor densities in selected brain regions

    Energy Technology Data Exchange (ETDEWEB)

    Weiland, N.G.; Wise, P.M.

    1987-11-01

    Norepinephrine regulates the proestrous and estradiol-induced LH surge by binding to alpha 1-adrenergic receptors. The density of alpha 1-receptors may be regulated by estradiol, photoperiod, and noradrenergic neuronal activity. We wished to determine whether alpha 1-receptors exhibit a diurnal rhythm in ovariectomized and/or estradiol-treated female rats, whether estradiol regulates alpha 1-receptors in those areas of brain involved with LH secretion and/or sexual behavior, and whether the concentrations of alpha-receptors vary inversely relative to previously reported norepinephrine turnover patterns. Young female rats, maintained on a 14:10 light-dark cycle were ovariectomized. One week later, half of them were outfitted sc with Silastic capsules containing estradiol. Groups of animals were decapitated 2 days later at 0300, 1000, 1300, 1500, 1800, and 2300 h. Brains were removed, frozen, and sectioned at 20 micron. Sections were incubated with (/sup 3/H)prazosin in Tris-HCl buffer, washed, dried, and exposed to LKB Ultrofilm. The densities of alpha 1-receptors were quantitated using a computerized image analysis system. In ovariectomized rats, the density of alpha 1-receptors exhibited a diurnal rhythm in the suprachiasmatic nucleus (SCN), medial preoptic nucleus (MPN), and pineal gland. In SCN and MPN, receptor concentrations were lowest during the middle of the day and rose to peak levels at 1800 h. In the pineal gland, the density of alpha 1-receptors was lowest at middark phase, rose to peak levels before lights on, and remained elevated during the day. Estradiol suppressed the density of alpha 1 binding sites in the SCN, MPN, median eminence, ventromedial nucleus, and the pineal gland but had no effect on the lateral septum. Estrogen treatment altered the rhythm of receptor densities in MPN, median eminence, and the pineal gland.

  7. Structure-based Understanding of Binding Affinity and Mode of Estrogen Receptor α Agonists and Antagonists.

    Science.gov (United States)

    The flexible hydrophobic ligand binding pocket (LBP) of estrogen receptor α (ERα) allows the binding of a wide variety of endocrine disruptors. Upon ligand binding, the LBP reshapes around the contours of the ligand and stabilizes the complex by complementary hydrophobic interact...

  8. CERAPP: Collaborative estrogen receptor activity prediction project

    DEFF Research Database (Denmark)

    Mansouri, Kamel; Abdelaziz, Ahmed; Rybacka, Aleksandra

    2016-01-01

    ). Risk assessors need tools to prioritize chemicals for evaluation in costly in vivo tests, for instance, within the U.S. EPA Endocrine Disruptor Screening Program. oBjectives: We describe a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project...... States and Europe to predict ER activity of a common set of 32,464 chemical structures. Quantitative structure-activity relationship models and docking approaches were employed, mostly using a common training set of 1,677 chemical structures provided by the U.S. EPA, to build a total of 40 categorical......: Individual model scores ranged from 0.69 to 0.85, showing high prediction reliabilities. Out of the 32,464 chemicals, the consensus model predicted 4,001 chemicals (12.3%) as high priority actives and 6,742 potential actives (20.8%) to be considered for further testing. conclusion: This project demonstrated...

  9. Evidence for estrogen receptor beta-selective activity of Vitex agnus-castus and isolated flavones.

    Science.gov (United States)

    Jarry, Hubertus; Spengler, Barbara; Porzel, Andrea; Schmidt, Juergen; Wuttke, Wolfgang; Christoffel, Volker

    2003-10-01

    Recent cell culture experiments indicated that extracts of Vitex agnus-castus (VAC) may contain yet unidentified phytoestrogens. Estrogenic actions are mediated via estrogen receptors (ER). To investigate whether VAC compounds bind to the currently known isoforms ERalpha or ERss, ligand binding assays (LBA) were performed. Subtype specific ER-LBA revealed a binding of VAC to ERss only. To isolate the ERss-selective compounds, the extract was fractionated by bio-guidance. The flavonoid apigenin was isolated and identified as the most active ERss-selective phytoestrogen in VAC. Other isolated compounds were vitexin and penduletin. These data demonstrate that the phytoestrogens in VAC are ERss-selective.

  10. Genetic analysis of the estrogen-related receptor alpha and studies of association with obesity and type 2 diabetes

    DEFF Research Database (Denmark)

    Larsen, L H; Rose, C S; Sparsø, T

    2007-01-01

    The estrogen-related receptor alpha (ERRalpha or NR3B1) is a transcription factor from the nuclear receptor super-family, group III. The gene encoding ERRalpha (ESRRA) is located on chromosome 11q13, a region showing genetic linkage to body mass index and fat percentage. Through interaction...

  11. Mechanism of estrogen activation of c-myc oncogene expression.

    Science.gov (United States)

    Dubik, D; Shiu, R P

    1992-08-01

    The estrogen receptor complex is a known trans-acting factor that regulates transcription of specific genes through an interaction with a specific estrogen-responsive cis-acting element (ERE). In previous studies we have shown that in estrogen-responsive human breast cancer cells estrogen rapidly activates c-myc expression. This activated expression occurs through enhanced transcription and does not require the synthesis of new protein intermediates; therefore, an ERE is present in the human c-myc gene regulatory region. To localize the ERE, constructs containing varying lengths of the c-myc 5'-flanking region ranging from -2327 to +25 (relative to the P1 promoter) placed adjacent to the chloramphenicol acetyl transferase reporter gene (CAT) were prepared. They were used in transient transfection studies in MCF-7 and HeLa cells co-transfected with an estrogen receptor expression vector. These studies reveal that all constructs containing the P2 promoter region exhibited estrogen-regulated CAT expression and that a 116-bp region upstream and encompassing the P2 TATA box is necessary for this activity. Analysis of this 116-bp region failed to identify a cis-acting element with sequences resembling the consensus ERE; however, co-transfection studies with mutant estrogen receptor expression vectors showed that the DNA-binding domain of the receptor is essential for estrogen-regulated CAT gene expression. We have also observed that anti-estrogen receptor complexes can weakly trans-activate from this 116-bp region but fail to do so from the ERE-containing ApoVLDLII-CAT construct. To explain these results we propose a new mechanism of estrogen trans-activation in the c-myc gene promoter.

  12. Expression of androgen receptor and estrogen receptor-alpha in the developing pituitary gland of male sheep lamb.

    Science.gov (United States)

    Huang, Li-Bo; Yuan, Xue-Jun

    2011-09-01

    To explore the expression of androgen receptor (AR) and estrogen receptor alpha (ERα) in the developing pituitary of male lamb, we detected AR and ERα expression in the anterior pituitary of lambs aged 2-7 months old by immunohistochemistry. The results showed that both AR immunoreactivity (AR-ir) and ERα immunoreactivity (ERα-ir) were localized in the nuclei of anterior pituitary cell. The percentage of the anterior pituitary cells expressing ERα fluctuated from 8.79±0.02% to 11.80±0.04% during the examined stages, but fell significantly to the lowest level at 6 months. While the proportion of AR-ir showed significant changes, it was in 11.52±1.26% at 2 months, it firstly increased to 19.86±1.03% at 3 months, and then significantly decreased to 8.18±1.17% at 6 months (Panterior pituitary cells. These results indicate that both AR and ERα are important in regulation of secretary function of anterior pituitary in sheep lamb, although the related mechanism needs to be elucidated further. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Estrogen Levels in the three Trimesters

    African Journals Online (AJOL)

    estrogen levels in first, second and third trimesters of pregnant albino rats. MATERIALS AND METHODS. TEST SUBJECTS. 20 female albino rats and 6 male albino rats, with initial weight of 165-180g were purchase from the animal house of Department of Animal and. Environmental Biology , University of Benin,. Benin city ...

  14. Prevalence of estrogen receptor alpha PvuII and XbaI polymorphism in population of Polish postmenopausal women.

    Directory of Open Access Journals (Sweden)

    Jozef Haczynski

    2008-01-01

    Full Text Available Numerous data indicate that polymorphism of estrogen receptor alpha (ERalpha may predict lipid levels, lipid response to hormone replacement therapy (HRT, myocardial infarction risk, bone fracture risk, bone mineral density (BMD and changes in BMD over time. In this study we aimed to evaluate distribution of ERalpha PvuII and XbaI genotypes in population of Polish postmenopausal women qualified to different protocols of HRT. Subject of the study were 64 consecutive postmenopausal women aged from 45 to 65 years (mean 56.6 assigned to HRT. ERalpha PvuII and XbaI polymorphism was determined by PCR-restriction fragment length polymorphism (RFLP. The absence of PvuII and XbaI restriction sites were indicated by "P" and "X" and presence by "p" and "x", respectively. PvuII genotype was distributed as follows: PP 17.2% (n=11, Pp 50% (n=32, pp 32.83% (n=21. Frequency of XbaI genotype was: XX 6.25% (n=4, Xx 34.4% (n=22, xx 59.4% (n=38. Four haplotypes with following frequencies were recognized: PX 17.3%, px 47.4%, Px 24.4% and pX 10.9%. Prevalence of estrogen receptor alpha PvuII and XbaI polymorphisms in Polish women is similar to previously studied population.

  15. Classical and Nonclassical Estrogen Receptor Action on Chromatin Templates

    National Research Council Canada - National Science Library

    Nordeen, Steven

    2000-01-01

    Improvement of hormone-based therapy in breast cancer and circumvention of its shortcomings is limited by the lack of detailed understanding of how steroids like estrogen work at a cellular and molecular level...

  16. Classical and Nonclassical Estrogen Receptor Action on Chromatin Templaces

    National Research Council Canada - National Science Library

    Nordeen, Steve

    2001-01-01

    Improvement of hormone-based therapy in breast cancer and circumvention of its shortcomings is limited by the lack of detailed understanding of how steroids like estrogen work at a cellular and molecular level...

  17. Estrogen receptor alpha localization in the testes of men with normal spermatogenesis Estrogen receptor alpha localization in the testes of men with normal spermatogenesis

    Directory of Open Access Journals (Sweden)

    Eliza Filipiak

    2012-10-01

    Full Text Available It is known that estrogens act on the male reproductive tract by binding to estrogen receptors (ER a and
    b. However, studies on ER localization in the human testis are discordant. The aim of this study was to investigate
    the localization of ERa in the testes of adult men with normal spermatogenesis. Semen analysis of ten adult men
    revealed azoospermia. FSH, LH and testosterone serum concentrations were within normal values, and the volume
    of the testes was normal, hence obstructive azoospermia was suspected. The tissues from testicular surgical
    biopsies were fixed in Bouin’s fluid and embedded in paraffin. Assessments of the seminiferous epithelium (scoring
    10 to –1, the number of Leydig cells (scoring 1 to 5, the areal fraction of intertubular space (IS, measurements
    of seminiferous tubule diameter, and the thickness of the tubular wall, were performed on microscopic
    sections. Immunohistochemical staining was applied with monoclonal antibodies against ERa. The mean spermatogenesis
    score was 10 points; IS — 30.6 ± 8.1%; seminiferous tubule diameter — 193.9 ± 19.4 μm; thickness of
    tubular wall — 7.44 ± 1.1 μm; number of Leydig cells — 1.6 ± 1.1 points. Immunohistochemical staining showed
    the localization of ERa to be in the Sertoli and Leydig cell cytoplasm, while ERa was absent in germ cells. The
    results of testicular tissue analysis confirmed its normal structure and normal, full spermatogenesis. The presence
    of ERa in Sertoli and Leydig cells in normal human testis demonstrated in this study suggests that estrogens may
    affect testicular function.It is known that estrogens act on the male reproductive tract by binding to estrogen receptors (ER a and
    b. However, studies on ER localization in the human testis are discordant. The aim of this study was to investigate
    the localization of ERa in the testes of adult men with normal spermatogenesis. Semen

  18. Molecular conformation, receptor binding, and hormone action of natural and synthetic estrogens and antiestrogens.

    Science.gov (United States)

    Duax, W L; Griffin, J F; Weeks, C M; Korach, K S

    1985-01-01

    The X-ray crystallographic structural determinations of synthetic estrogens and antiestrogens provide reliable information on the global minimum energy conformation of these molecules or a local minimum energy conformation that is within 1 or 2 kcal/mole of the global minimum. In favorable cases, state-of-the-art molecular mechanics calculations provide quantitative agreement with X-ray results and information on the relative energy of other local minimum energy conformations not observed crystallographically. Because the conformation of diethylstilbestrol (DES) observed in solvated crystals has an overall conformation and dipole moment more similar to estradiol it is the form more likely to bind to the receptor and produce hormone activity. Either phenol ring of DES can successfully mimic the estradiol A-ring in binding to the receptor. Indenestrol A (INDA) and indenestrol B (INDB) have nearly identical fully extended planar conformations. Either the alpha or gamma rings of these compounds may mimic the A ring of estradiol and compete for the estrogen receptor. Although there are eight distinct ways in which molecules of a racemic mixture of INDA or INDB can bind to the receptor, not all of them may be able to elicit a hormonal response. This may account for the reduced biological activity of the compounds despite their successful competition for receptor binding. The minimum energy conformations of Z-pseudodiethylstilbestrol (ZPD) and E-pseudodiethylstilbestrol (EPD) are bent in a fashion similar to that of indanestrol (INDC). These molecules have good binding affinity suggesting that the receptor does not require a flat molecule. Therefore these conformations would appear to be compatible with receptor binding, but only the Z isomer has an energetically allowed extended conformation that accounts for its observed biological activity relative to DES. PMID:3905370

  19. Histone demethylase JMJD2B functions as a co-factor of estrogen receptor in breast cancer proliferation and mammary gland development.

    Directory of Open Access Journals (Sweden)

    Masahito Kawazu

    2011-03-01

    Full Text Available Estrogen is a key regulator of normal function of female reproductive system and plays a pivotal role in the development and progression of breast cancer. Here, we demonstrate that JMJD2B (also known as KDM4B constitutes a key component of the estrogen signaling pathway. JMJD2B is expressed in a high proportion of human breast tumors, and that expression levels significantly correlate with estrogen receptor (ER positivity. In addition, 17-beta-estradiol (E2 induces JMJD2B expression in an ERα dependent manner. JMJD2B interacts with ERα and components of the SWI/SNF-B chromatin remodeling complex. JMJD2B is recruited to ERα target sites, demethylates H3K9me3 and facilitates transcription of ER responsive genes including MYB, MYC and CCND1. As a consequence, knockdown of JMJD2B severely impairs estrogen-induced cell proliferation and the tumor formation capacity of breast cancer cells. Furthermore, Jmjd2b-deletion in mammary epithelial cells exhibits delayed mammary gland development in female mice. Taken together, these findings suggest an essential role for JMJD2B in the estrogen signaling, and identify JMJD2B as a potential therapeutic target in breast cancer.

  20. Inhibition of neointima formation by local delivery of estrogen receptor alpha and beta specific agonists

    NARCIS (Netherlands)

    Krom, Y.D.; Pires, N.M.M.; Jukema, J.W.; Vries, M.R. de; Frants, R.R.; Havekes, L.M.; Dijk, K.W. van; Quax, P.H.A.

    2007-01-01

    Objective: Neointima formation is the underlying mechanism of (in-stent) restenosis. 17β-Estradiol (E2) is known to inhibit injury-induced neointima formation and post-angioplasty restenosis. Estrogen receptor alpha (ERα) has been demonstrated to mediate E2 anti-restenotic properties. However, the

  1. Estrogen Receptor Folding Modulates cSrc Kinase SH2 Interaction via a Helical Binding Mode

    NARCIS (Netherlands)

    Nieto, Lidia; Tharun, Inga M; Balk, Mark; Wienk, Hans; Boelens, Rolf; Ottmann, Christian; Milroy, Lech-Gustav; Brunsveld, Luc

    2015-01-01

    The estrogen receptors (ERs) feature, next to their transcriptional role, important nongenomic signaling actions, with emerging clinical relevance. The Src Homology 2 (SH2) domain mediated interaction between cSrc kinase and ER plays a key role in this; however the molecular determinants of this

  2. Estrogen receptor folding modulates cSrc kinase SH2 interaction via a helical binding mode

    NARCIS (Netherlands)

    Nieto, L.; Tharun, I.M.; Balk, M.; Wienk, H.; Boelens, R.; Ottmann, C.; Milroy, L.-G.; Brunsveld, L.

    2015-01-01

    The estrogen receptors (ERs) feature, next to their transcriptional role, important nongenomic signaling actions, with emerging clinical relevance. The Src Homology 2 (SH2) domain mediated interaction between cSrc kinase and ER plays a key role in this; however the molecular determinants of this

  3. Visualizing estrogen receptor-a-expressing neurons using a new ERa-ZsGreen reporter mouse line

    Science.gov (United States)

    A variety of biological functions of estrogens, including regulation of energy metabolism, are mediated by neurons expressingestrogen receptor-a (ERa) in the brain. However, complex intracellular processes in these ERa-expressing neurons are difficult to unravel, due to the lack of strategy to visua...

  4. Palmitoylation regulates 17β-estradiol-induced estrogen receptor-α degradation and transcriptional activity.

    Science.gov (United States)

    La Rosa, Piergiorgio; Pesiri, Valeria; Leclercq, Guy; Marino, Maria; Acconcia, Filippo

    2012-05-01

    The estrogen receptor-α (ERα) is a transcription factor that regulates gene expression through the binding to its cognate hormone 17β-estradiol (E2). ERα transcriptional activity is regulated by E2-evoked 26S proteasome-mediated ERα degradation and ERα serine (S) residue 118 phosphorylation. Furthermore, ERα mediates fast cell responses to E2 through the activation of signaling cascades such as the MAPK/ERK and phosphoinositide-3-kinase/v-akt murine thymoma viral oncogene homolog 1 pathways. These E2 rapid effects require a population of the ERα located at the cell plasma membrane through palmitoylation, a dynamic enzymatic modification mediated by palmitoyl-acyl-transferases. However, whether membrane-initiated and transcriptional ERα activities integrate in a unique picture or represent parallel pathways still remains to be firmly clarified. Hence, we evaluated here the impact of ERα palmitoylation on E2-induced ERα degradation and S118 phosphorylation. The lack of palmitoylation renders ERα more susceptible to E2-dependent degradation, blocks ERα S118 phosphorylation and prevents E2-induced ERα estrogen-responsive element-containing promoter occupancy. Consequently, ERα transcriptional activity is prevented and the receptor addressed to the nuclear matrix subnuclear compartment. These data uncover a circuitry in which receptor palmitoylation links E2-dependent ERα degradation, S118 phosphorylation, and transcriptional activity in a unique molecular mechanism. We propose that rapid E2-dependent signaling could be considered as a prerequisite for ERα transcriptional activity and suggest an integrated model of ERα intracellular signaling where E2-dependent early extranuclear effects control late receptor-dependent nuclear actions.

  5. Epigenetic Basis for the Regulation of Estrogen Receptor Alpha Activity in Breast Cancer Cells

    Science.gov (United States)

    2009-04-01

    Contreras, J.I., Prescott , M.S., Dagenais, S.L., Wu, R., Yee, J., Orringer, M.B., Misek, D.E., Hanash, S.M., et al. (2002). The hepatocyte nuclear... Microbiology . All Rights Reserved. Coactivator Function Defines the Active Estrogen Receptor Alpha Cistrome† Mathieu Lupien,1‡ Jérôme Eeckhoute,1

  6. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Kazuhiro [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Tsukui, Tohru [Experimental Animal Laboratory, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Imazawa, Yukiko; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively active mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  7. Estrogens and Cognition: Friends or Foes?

    Science.gov (United States)

    Korol, Donna L.; Pisani, Samantha L.

    2015-01-01

    Estrogens are becoming well known for their robust enhancement on cognition particularly for learning and memory that relies upon functioning of the hippocampus and related neural systems. What is also emerging is that estrogen modulation of cognition is not uniform, at times enhancing yet at other times impairing learning. This review explores the bidirectional effects of estrogens on learning from a multiple memory systems view, focusing on the hippocampus and striatum, whereby modulation by estrogens sorts according to task attributes and neural systems engaged during cognition. We highlight our findings that show the ability to solve hippocampus-sensitive tasks typically improves under relatively high estrogen status while the ability to solve striatum-sensitive tasks degrades with estrogen exposures. Though constrained by dose and timing of exposure, these opposing enhancements and impairments of cognition can be observed following treatments with different estrogenic compounds including the hormone estradiol, the isoflavone genistein found in soybeans, and agonists that are selective for specific estrogen receptors, suggesting that activation of a single receptor type is sufficient to produce the observed shifts in learning strategies. Using this multi-dimensional framework will allow us to extend our thinking of the relationship between estrogens and cognition to other brain regions and cognitive functions. PMID:26149525

  8. Estrogen receptor-alpha distribution in the human hypothalamus in relation to sex and endocrine status

    NARCIS (Netherlands)

    Kruijver, Frank P. M.; Balesar, Rawien; Espila, Ana M.; Unmehopa, Unga A.; Swaab, Dick F.

    2002-01-01

    The present study reports the first systematic rostrocaudal distribution of estrogen receptor-a immunoreactivity (ERalpha-ir) in the human hypothalamus and its adjacent areas in young adults. Postmortem material taken from 10 subjects (five male and five female), between 20 and 39 years of age, was

  9. Estrogen and progesterone receptors in human decidua after RU486 treatment.

    Science.gov (United States)

    Shi, W L; Wang, J D; Fu, Y; Zhu, P D

    1993-07-01

    To examine RU486 action on decidua at the level of cellular estrogen receptor (ER) and P receptor (PR). Controlled basic study for contragestion mechanism of mifepristone. Normal human volunteers in an academic research environment. Sixty women with 6 to 7 weeks of gestation who voluntarily requested termination of pregnancy were recruited and randomly divided into three groups. A single dose of 200 mg RU486 was orally administered to the two treatment groups 12 and 24 hours, respectively, before surgical interruption of pregnancies. Placebo was used for control group. Decidual tissues were collected right after operation. Immunocytochemical reactions of PR and ER in decidua after RU486 treatment were compared with the control subjects. The differences of the reaction in decidual area with or without trophoblast invasion were noted. RU486 treatment increased PR and ER staining in vessel and stroma of decidua without trophoblast invasion (decidua parietalis) but not in decidua with trophoblast invasion (decidua capsularis or basalis). Chi-squared analysis indicated a significant increase in the number of ER-positive samples after RU486 treatment. The decidua parietalis was the primary target site of RU486. The lack of RU486 effect on decidua capsularis implied that trophoblast invasion prevented against antiprogestin impact.

  10. Vitex Agnus Castus Extract Improves Learning and Memory and Increases the Transcription of Estrogen Receptor α in Hippocampus of Ovariectomized Rats.

    Science.gov (United States)

    Allahtavakoli, Mohammad; Honari, Najmeh; Pourabolli, Iran; Kazemi Arababadi, Mohammad; Ghafarian, Hossein; Roohbakhsh, Ali; Esmaeili Nadimi, Ali; Shamsizadeh, Ali

    2015-07-01

    Lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. Although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormone-dependent cancers. Phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitive decline. 24 female Wistar rats weighing 180-220 g were used in this study. The animals were ovariectomized and randomly divided into four groups including, control and two groups which received 8 and 80 mg/kg Vitex agnus castus (VAC) ethanolic extract orally. The last groups were treated with 40 μg/kg of estradiol valerat. Step-through passive avoidance (STPA) test was used for the evaluation of learning and memory. The hippocampal estrogen receptor α (ERα) expression was measured using Real-Time PCR. The results demonstrated that VAC extract or estradiol had better performance on step-through passive avoidance test than control group (all P<0.05). Moreover, administration of either estradiol or VAC extract increased the hippocampal mRNA level of ERα and prevented the decrease in uterine weight of ovariectomized rats. Based on our data, VAC extract improves learning and memory in ovariectomized rats. The positive effect of VAC extract on learning and memory is possibly associated with an increase in ERα gene expression in the hippocampal formation.

  11. Testosterone and 17β-estradiol have opposite effects on podocyte apoptosis that precedes glomerulosclerosis in female estrogen receptor knockout mice.

    Science.gov (United States)

    Doublier, Sophie; Lupia, Enrico; Catanuto, Paola; Periera-Simon, Simone; Xia, Xiaomei; Korach, Ken; Berho, Mariana; Elliot, Sharon J; Karl, Michael

    2011-02-01

    Podocyte damage and apoptosis are thought to be important if not essential in the development of glomerulosclerosis. Female estrogen receptor knockout mice develop glomerulosclerosis at 9 months of age due to excessive ovarian testosterone production and secretion. Here, we studied the pathogenesis of glomerulosclerosis in this mouse model to determine whether testosterone and/or 17β-estradiol directly affect the function and survival of podocytes. Glomerulosclerosis in these mice was associated with the expression of desmin and the loss of nephrin, markers of podocyte damage and apoptosis. Ovariectomy preserved the function and survival of podocytes by eliminating the source of endogenous testosterone production. In contrast, testosterone supplementation induced podocyte apoptosis in ovariectomized wild-type mice. Importantly, podocytes express functional androgen and estrogen receptors, which, upon stimulation by their respective ligands, have opposing effects. Testosterone induced podocyte apoptosis in vitro by androgen receptor activation, but independent of the TGF-β1 signaling pathway. Pretreatment with 17β-estradiol prevented testosterone-induced podocyte apoptosis, an estrogen receptor-dependent effect mediated by activation of the ERK signaling pathway, and protected podocytes from TGF-β1- or TNF-α-induced apoptosis. Thus, podocytes are target cells for testosterone and 17β-estradiol. These hormones modulate podocyte damage and apoptosis.

  12. In silico study of curcumol, curcumenol, isocurcumenol, and β-sitosterol as potential inhibitors of estrogen receptor alpha of breast cancer

    OpenAIRE

    Resmi Mustarichiei; Jutti Levitas; Jopi Arpina

    2014-01-01

    Background: Based on data from the Hospital Information System (HIS) in 2007, breast cancer is the top ranked diagnosed cancer in Indonesia. Estrogen receptor alpha (ERα) is associated with breast cancer because it is found in high levels in cancer tissues. Curcumol, curcumenol, isocurcumenol of white tumeric rhizomes (Curcuma zedoaria (Christm.) Roscoe), and β-sitosterol from seeds of pumpkin (Cucurbita pepo L.) have been reported to have inhibitory activity against cancer cells. This study ...

  13. Estrogen and the female heart.

    Science.gov (United States)

    Knowlton, A A; Korzick, D H

    2014-05-25

    Estrogen has a plethora of effects in the cardiovascular system. Studies of estrogen and the heart span human clinical trials and basic cell and molecular investigations. Greater understanding of cell and molecular responses to estrogens can provide further insights into the findings of clinical studies. Differences in expression and cellular/intracellular distribution of the two main receptors, estrogen receptor (ER) α and β, are thought to account for the specificity and differences in responses to estrogen. Much remains to be learned in this area, but cellular distribution within the cardiovascular system is becoming clearer. Identification of GPER as a third ER has introduced further complexity to the system. 17β-estradiol (E2), the most potent human estrogen, clearly has protective properties activating a signaling cascade leading to cellular protection and also influencing expression of the protective heat shock proteins (HSP). E2 protects the heart from ischemic injury in basic studies, but the picture is more involved in the whole organism and clinical studies. Here the complexity of E2's widespread effects comes into play and makes interpretation of findings more challenging. Estrogen loss occurs primarily with aging, but few studies have used aged models despite clear evidence of differences between the response to estrogen deficiency in adult and aged animals. Thus more work is needed focusing on the effects of aging vs. estrogen loss on the cardiovascular system. Published by Elsevier Ireland Ltd.

  14. Biochemical and immunohistochemical estrogen and progesterone receptors in adenomatous hyperplasia and endometrial carcinoma: correlations with stage and other clinicopathologic features

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, A L; Lyndrup, J

    1992-01-01

    OBJECTIVE: This study investigates clinicopathologic associations of estrogen and progesterone receptor content in endometrial carcinoma. STUDY DESIGN: One hundred fifty-two patients with endometrial cancer and 12 with adenomatous hyperplasia were included. Dextran-coated charcoal receptor assay...... receptor dextran-coated charcoal values and immunohistochemical histologic scores correlated inversely (p dextran-coated charcoal values was independent...

  15. Changes in androgen receptor, estrogen receptor alpha, and sexual behavior with aging and testosterone in male rats.

    Science.gov (United States)

    Wu, Di; Gore, Andrea C

    2010-07-01

    Reproductive aging in males is characterized by a diminution in sexual behavior beginning in middle age. We investigated the relationships among testosterone, androgen receptor (AR) and estrogen receptor alpha (ERalpha) cell numbers in the hypothalamus, and their relationship to sexual performance in male rats. Young (3months) and middle-aged (12months) rats were given sexual behavior tests, then castrated and implanted with vehicle or testosterone capsules. Rats were tested again for sexual behavior. Numbers of AR and ERalpha immunoreactive cells were counted in the anteroventral periventricular nucleus and the medial preoptic nucleus, and serum hormones were measured. Middle-aged intact rats had significant impairments of all sexual behavior measures compared to young males. After castration and testosterone implantation, sexual behaviors in middle-aged males were largely comparable to those in the young males. In the hypothalamus, AR cell density was significantly (5-fold) higher, and ERalpha cell density significantly (6-fold) lower, in testosterone- than vehicle-treated males, with no age differences. Thus, restoration of serum testosterone to comparable levels in young and middle-aged rats resulted in similar preoptic AR and ERalpha cell density concomitant with a reinstatement of most behaviors. These data suggest that age-related differences in sexual behavior cannot be due to absolute levels of testosterone, and further, the middle-aged brain retains the capacity to respond to exogenous testosterone with changes in hypothalamic AR and ERalpha expression. Our finding that testosterone replacement in aging males has profound effects on hypothalamic receptors and behavior has potential medical implications for the treatment of age-related hypogonadism in men. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Estrogen receptors in human thyroid gland. An immunohistochemical study

    International Nuclear Information System (INIS)

    Arain, Shaukat A.; Shah, Munawar H.; Jamal, Qamar; Meo, Sultan A.

    2003-01-01

    The objective of this study is to determine the estrogen receptors (ER) status (present in the nucleous of cell) in the thyroid gland tissues. For this purpose 50 previously diagnosed cases of various thyroid lesions were selected from the Surgical Pathology Records of Pathology Department, Basic Medical Sciences Institute,Jinnah Postgraduate. Medical Center,Karachi,Pakistan between March and August 2000.The staining was performed on formalin fixed paraffin embeded tissues using monoclonal anti-ER anti-body (clone1D5).Out of 50 cases,8 were noduler goiter,9 cases of adenoma 19 papillary carcinoma, 10 follicular and 4 cases were of medullary carcinoma. Surrounding normal tissue was available in 25 (50%) cases, 4 non-neoplastic and 21 neoplastic lesions.Out of 50 cases ,10(20%) and 40(80%) were females, the youngest patient was a 15-year-old female and the eldest patient was a 56-years-old male. Despite the availability of normal thyroid tissue and a wide range of lesions, none of our cases showed the positive staining. In contrary to many earlier reports by immunohistochemical method using monoclonal antibody (clone1D5) on formalin- fixed praffin-embedded thyroid tissues, the ER is not detectable. The effect of Estrogen on thyroid gland may be indirect one. (author)

  17. Tyrosine dephosphorylation enhances the therapeutic target activity of epidermal growth factor receptor (EGFR) by disrupting its interaction with estrogen receptor (ER).

    Science.gov (United States)

    Ma, Shao; Yin, Ning; Qi, Xiaomei; Pfister, Sandra L; Zhang, Mei-Jie; Ma, Rong; Chen, Guan

    2015-05-30

    Protein-protein interactions can increase or decrease its therapeutic target activity and the determining factors involved, however, are largely unknown. Here, we report that tyrosine-dephosphorylation of epidermal growth factor receptor (EGFR) increases its therapeutic target activity by disrupting its interaction with estrogen receptor (ER). Protein tyrosine phosphatase H1 (PTPH1) dephosphorylates the tyrosine kinase EGFR, disrupts its interaction with the nuclear receptor ER, and increases breast cancer sensitivity to small molecule tyrosine kinase inhibitors (TKIs). These effects require PTPH1 catalytic activity and its interaction with EGFR, suggesting that the phosphatase may increase the sensitivity by dephosphorylating EGFR leading to its dissociation with ER. Consistent with this notion, a nuclear-localization defective ER has a higher EGFR-binding activity and confers the resistance to TKI-induced growth inhibition. Additional analysis show that PTPH1 stabilizes EGFR, stimulates the membranous EGFR accumulation, and enhances the growth-inhibitory activity of a combination therapy of TKIs with an anti-estrogen. Since EGFR and ER both are substrates for PTPH1 in vitro and in intact cells, these results indicate that an inhibitory EGFR-ER protein complex can be switched off through a competitive enzyme-substrate binding. Our results would have important implications for the treatment of breast cancer with targeted therapeutics.

  18. Synthesis and biological evaluation of guanylhydrazone coactivator binding inhibitors for the estrogen receptor.

    Science.gov (United States)

    LaFrate, Andrew L; Gunther, Jillian R; Carlson, Kathryn E; Katzenellenbogen, John A

    2008-12-01

    Most patients with hormone-responsive breast cancer eventually develop resistance to traditional antiestrogens such as tamoxifen, and this has become a major obstacle in their treatment. We prepared and characterized the activity of a series of 16 guanylhydrazone small molecules that are designed to block estrogen receptor (ER) activity through a non-traditional mechanism, by directly interfering with coactivator binding to agonist-liganded ER. The inhibitory activity of these compounds was determined in cell-based transcription assays using ER-responsive reporter gene and mammalian two-hybrid assays. Several of the compounds gave IC(50) values in the low micromolar range. Two secondary assays were used to confirm that these compounds were acting through the proposed non-traditional mode of estrogen inhibitory action and not as conventional antagonists at the ligand binding site.

  19. The ginsenoside PPD exerts anti-endometriosis effects by suppressing estrogen receptor-mediated inhibition of endometrial stromal cell autophagy and NK cell cytotoxicity.

    Science.gov (United States)

    Zhang, Bing; Zhou, Wen-Jie; Gu, Chun-Jie; Wu, Ke; Yang, Hui-Li; Mei, Jie; Yu, Jia-Jun; Hou, Xiao-Fan; Sun, Jian-Song; Xu, Feng-Yuan; Li, Da-Jin; Jin, Li-Ping; Li, Ming-Qing

    2018-05-14

    Endometriosis (EMS) is an estrogen-dependent gynecological disease with a low autophagy level of ectopic endometrial stromal cells (eESCs). Impaired NK cell cytotoxic activity is involved in the clearance obstruction of the ectopic endometrial tissue in the abdominopelvic cavity. Protopanaxadiol (PPD) and protopanaxatriol (PPT) are two metabolites of ginsenosides, which have profound biological functions, such as anti-cancer activities. However, the role and mechanism of ginsenosides and metabolites in endometriosis are completely unknown. Here, we found that the compounds PPD, PPT, ginsenoside-Rg3 (G-Rg3), ginsenoside-Rh2 (G-Rh2), and esculentoside A (EsA) led to significant decreases in the viability of eESCs, particularly PPD (IC50 = 30.64 µM). In vitro and in vivo experiments showed that PPD promoted the expression of progesterone receptor (PR) and downregulated the expression of estrogen receptor α (ERα) in eESCs. Treatment with PPD obviously induced the autophagy of eESCs and reversed the inhibitory effect of estrogen on eESC autophagy. In addition, eESCs pretreated with PPD enhanced the cytotoxic activity of NK cells in response to eESCs. PPD decreased the numbers and suppressed the growth of ectopic lesions in a mouse EMS model. These results suggest that PPD plays a role in anti-EMS activation, possibly by restricting estrogen-mediated autophagy regulation and enhancing the cytotoxicity of NK cells. This result provides a scientific basis for potential therapeutic strategies to treat EMS by PPD or further structural modification.

  20. Determination and confirmation of selective estrogen receptor modulators (SERMs), anti-estrogens and aromatase inhibitors in bovine and porcine urine using UHPLC-MS/MS.

    Science.gov (United States)

    Meijer, Thijs; Essers, Martien L; Kaklamanos, George; Sterk, Saskia S; van Ginkel, Leendert A

    2017-04-01

    Selective estrogen receptor modulators (SERMs), anti-estrogens and aromatase inhibitors are prohibited in human sports doping. However, they also present a risk of being used illegally in animal husbandry for fattening purposes. A method was developed and validated using UHPLC-MS/MS for the determination and confirmation of SERMs, anti-estrogens and aromatase inhibiters in bovine and porcine urine. This method was used in a survey of more than 200 bovine and porcine urine samples from Dutch farms. In 18 out of 103 porcine urine samples (17%) and two out of 114 bovine samples (2%) formestane, an aromatase inhibitor, was detected. None of the other compounds was detected. From human doping control it is known that formestane can, in some cases, be of natural origin. Analyses of reference samples from untreated bovine and porcine animals demonstrated the presence of formestane in bovine animals, but not yet in porcine animals. Future research will focus on whether the detected formestane in porcine and bovine urine is from endogenous or exogenous origin, using GC-c-IRMS.

  1. Factors affecting estrogen receptor status in a multiracial Asian country : An analysis of 3557 cases

    NARCIS (Netherlands)

    Yip, C. H.; Pathy, N. Bhoo; Uiterwaal, C. S.; Taib, N. A.; Tan, G. H.; Mun, K. S.; Choo, W. Y.; Rhodes, A.

    Estrogen receptor (ER) positive rates in breast cancer may be influenced by grade, stage, age and race. This study reviews the ER positive rates over a 15-year period at the University Malaya Medical Centre, Kuala Lumpur, Malaysia. Data on ER status of 3557 patients from 1994 to 2008 was analyzed.

  2. Lipid-rich carcinoma of the breast that is strongly positive for estrogen receptor: a case report and literature review

    Directory of Open Access Journals (Sweden)

    Oba T

    2016-03-01

    Full Text Available Takaaki Oba,1 Mayu Ono,1 Asumi Iesato,1 Toru Hanamura,1 Takayuki Watanabe,1 Tokiko Ito,1 Toshiharu Kanai,1 Kazuma Maeno,1 Ken-ichi Ito,1 Ayako Tateishi,2 Akihiko Yoshizawa,2 Fumiyoshi Takayama31Division of Breast, Endocrine and Respiratory Surgery, Department of Surgery, Shinshu University School of Medicine, Matsumoto, Nagano, 2Department of Laboratory Medicine, Shinshu University Hospital, 3Imaging Center, Ichinose Neurosurgical Hospital, Matsumoto, JapanAbstract: Lipid-rich carcinoma (LRC of the breast is a rare breast cancer variant that accounts for <1% of all breast malignancies. It has been reported that LRCs are negative for estrogen receptor. Here, we report a case of LRC of the breast that was strongly positive for estrogen receptor and treated with endocrine adjuvant therapy. A 52-year-old postmenopausal female noticed a lump in her right breast by self-examination and presented to our hospital. Physical examination revealed an elastic 30 mm ×20 mm hard mass in the upper medial part of her right breast. The findings obtained using ultrasonography, mammography, and contrast-enhanced magnetic resonance imaging suggested breast cancer. Core needle biopsy resulted in the diagnosis of invasive carcinoma. The patient underwent mastectomy and sentinel lymph node biopsy. Histopathologically, the tumor cells were abundant in foamy cytoplasm. Because the presence of marked cytoplasmic lipid droplets was confirmed by Sudan IV staining and electron microscopic examination of the tumor and the lipid droplets were negative for periodic acid–Schiff staining, the tumor was diagnosed as an LRC. Immunohistochemically, estrogen and progesterone receptors of the tumor were strongly positive, human epidermal growth factor receptor type 2 was negative, and the ratio of Ki-67-positive cells was ~30%. After surgery, the patient underwent combination chemotherapy with anthracycline, cyclophosphamide, and 5-fluorouracil, followed by docetaxel. Thereafter

  3. American Society of Clinical Oncology/College Of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer.

    NARCIS (Netherlands)

    Hammond, M.E.; Hayes, D.F.; Dowsett, M.; Allred, D.C.; Hagerty, K.L.; Badve, S.; Fitzgibbons, P.L.; Francis, G.; Goldstein, N.S.; Hayes, M.; Hicks, D.G.; Lester, S.; Love, R.; Mangu, P.B.; McShane, L.; Miller, K.; Osborne, C.K.; Paik, S.; Perlmutter, J.; Rhodes, A.; Sasano, H.; Schwartz, J.N.; Sweep, F.C.; Taube, S.; Torlakovic, E.E.; Valenstein, P.; Viale, G.; Visscher, D.; Wheeler, T.; Williams, R.B.; Wittliff, J.L.; Wolff, A.C.

    2010-01-01

    PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of

  4. American Society of Clinical Oncology/College of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer.

    NARCIS (Netherlands)

    Hammond, M.E.; Hayes, D.F.; Dowsett, M.; Allred, D.C.; Hagerty, K.L.; Badve, S.; Fitzgibbons, P.L.; Francis, G.; Goldstein, N.S.; Hayes, M.; Hicks, D.G.; Lester, S.; Love, R.; Mangu, P.B.; McShane, L.; Miller, K.; Osborne, C.K.; Paik, S.; Perlmutter, J.; Rhodes, A.; Sasano, H.; Schwartz, J.N.; Sweep, F.C.; Taube, S.; Torlakovic, E.E.; Valenstein, P.; Viale, G.; Visscher, D.; Wheeler, T.; Williams, R.B.; Wittliff, J.L.; Wolff, A.C.

    2010-01-01

    PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of

  5. In Vivo Anti-estrogenic Effects of Menadione on Hepatic Estrogen-responsive Gene Expression in Male Medaka (Oryzias latipes)

    OpenAIRE

    Yamaguchi, Akemi; Kohra, Shinya; Ishibashi, Hiroshi; Arizono, Koji; Tominaga, Nobuaki

    2008-01-01

    Menadione, a synthetic vitamin K3, exhibits anti-estrogenic activity on in vitro assay. However, the in vivo anti-estrogenic effects of menadione have not been determined, while correlations between biological effects and structural changes are unclear. Thus, we investigated the in vivo anti-estrogenic activity of menadione under fluorescent light and dark conditions. Suppression of the hepatic estrogen response genes vitellogenin1 (VTG1), VTG2 and estrogen receptor-α (ER-α) was used as an in...

  6. Organochlorine exposures influence on breast cancer risk and survival according to estrogen receptor status: a Danish cohort-nested case-control study

    International Nuclear Information System (INIS)

    Høyer, Annette P; Jørgensen, Torben; Rank, Fritz; Grandjean, Philippe

    2001-01-01

    The relationship between breast cancer and organochlorine exposure is controversial and complex. As estrogen receptor positive and negative breast cancer may represent different entities of the disease, this study was undertaken to evaluate organochlorines influence on breast cancer risk and survival according to receptor status. The background material stems from the Copenhagen City Heart Study (Denmark 1976-78). The breast cancer risk was investigated in a cohort nested case-control design including 161 cases and twice as many breast cancer free controls. The cases served as a cohort in the survival analysis. Serum organochlorine concentrations were determined by gaschromotography. The observed increased breast cancer risk associated with exposure to dieldrin derived from women who developed an estrogen receptor negative (ERN) tumor (Odds ratio [OR] I vs. IV quartile, 7.6, 95% confidence interval [95% CI] 1.4-46.1, p-value for linear trend 0.01). Tumors in women with the highest dieldrin serum level were larger and more often spread at the time of diagnosis than ERP tumors. The risk of dying was for the remaining evaluated compounds higher among patients with ERP breast cancer when compared to those with ERN. In the highest quartile of polychlorinated biphenyls (ΣPCB) it was more than 2-fold increased (Relative risk [RR] I vs. IV quartile, 2.5, 95% CI 1.1-5.7), but no dose-response relation was apparent. The results do not suggest that exposure to potential estrogenic organochlorines leads to development of an ERP breast cancer. A possible adverse effect on prognosis of hormone-responsive breast cancers needs to be clarified

  7. Estrogen receptors in the human male bladder, prostatic urethra, and prostate. An immunohistochemical and biochemical study

    DEFF Research Database (Denmark)

    Bødker, A; Balslev, E; Juul, B R

    1995-01-01

    The distribution and quantity of estrogen receptors (ERs) in the human male bladder, prostatic urethra and the prostate were studied in eight males with recurrent papillomas of the bladder or monosymptomatic hematuria (median age 61 years), 14 men undergoing transurethral resection due to benign...

  8. Regulation of DNA Damage Response by Estrogen Receptor β-Mediated Inhibition of Breast Cancer Associated Gene 2

    Directory of Open Access Journals (Sweden)

    Yuan-Hao Lee

    2015-04-01

    Full Text Available Accumulating evidence suggests that ubiquitin E3 ligases are involved in cancer development as their mutations correlate with genomic instability and genetic susceptibility to cancer. Despite significant findings of cancer-driving mutations in the BRCA1 gene, estrogen receptor (ER-positive breast cancers progress upon treatment with DNA damaging-cytotoxic therapies. In order to understand the underlying mechanism by which ER-positive breast cancer cells develop resistance to DNA damaging agents, we employed an estrogen receptor agonist, Erb-041, to increase the activity of ERβ and negatively regulate the expression and function of the estrogen receptor α (ERα in MCF-7 breast cancer cells. Upon Erb-041-mediated ERα down-regulation, the transcription of an ERα downstream effector, BCA2 (Breast Cancer Associated gene 2, correspondingly decreased. The ubiquitination of chromatin-bound BCA2 was induced by ultraviolet C (UVC irradiation but suppressed by Erb-041 pretreatment, resulting in a blunted DNA damage response. Upon BCA2 silencing, DNA double-stranded breaks increased with Rad51 up-regulation and ataxia telangiectasia mutated (ATM activation. Mechanistically, UV-induced BCA2 ubiquitination and chromatin binding were found to promote DNA damage response and repair via the interaction of BCA2 with ATM, γH2AX and Rad51. Taken together, this study suggests that Erb-041 potentiates BCA2 dissociation from chromatin and co-localization with Rad51, resulting in inhibition of homologous recombination repair.

  9. The relationship of cerb B 2 expression with estrogen receptor and progesterone receptor and prognostic parameters in endometrial carcinomas

    Directory of Open Access Journals (Sweden)

    Kandemir Nilufer

    2010-02-01

    Full Text Available Abstract Background Endometrial carcinoma (EC is the most common malignancy of the female genital tract. Gene alterations and overexpression of various oncogenes are important in tumor development. The human HER 2 neu (c-erbB-2 gene product is a transmembrane receptor with an intracellular tyrosine kinase that plays an important role in coordinating the endometrial growth factor receptor signaling network. The aim of this study was to investigate the expression of c-erbB-2 in endometrial cancer, to study its correlation to established prognostic parameters and estrogen receptor (ER and progesterone receptor (PR status. Methods Immunohistochemical (IHC analyses of ER, PR and c-erbB-2 were performed in 72 EC cases. Results We detected a positive staining with c erbB 2 in 18.1% of the cases and determined a statistically significant relation between c-erbB-2 and PR. We could not find a statistically significant relation between c-erbB-2 staining and ER. There was not a statistically significant difference between c-erbB-2 and histological grade. The highest level of c-erbB-2 was found in grade 2 cases. There was not any statistically significant relation between c-erbB-2 and menstrual status, myometrial invasion, lymph node status, stage and survival. Conclusions Although our study provides additional evidence of the potential prognostic role of c-erbB-2, further prospective and controlled studies are required to validate their clinical usefulness.

  10. Quantification of Estrogen Receptor Expression in Normal Breast Tissue in Postmenopausal Women With Breast Cancer and Association With Tumor Subtypes.

    Science.gov (United States)

    Gulbahce, H Evin; Blair, Cindy K; Sweeney, Carol; Salama, Mohamed E

    2017-09-01

    Estrogen exposure is important in the pathogenesis of breast cancer and is a contributing risk factor. In this study we quantified estrogen receptor (ER) alpha expression in normal breast epithelium (NBR) in women with breast cancer and correlated it with breast cancer subtypes. Tissue microarrays were constructed from 204 breast cancer patients for whom normal breast tissue away from tumor was available. Slides stained with ER were scanned and expression in normal terminal duct lobular epithelium was quantitated using computer-assisted image analysis. ER expression in normal terminal duct lobular epithelium of postmenopausal women with breast cancer was significantly associated with estrogen and triple (estrogen, progesterone receptors, and HER2) negative phenotypes. Also increased age at diagnosis was significantly associated with ER expression in NBR. ER positivity in normal epithelium did not vary by tumor size, lymph node status, tumor grade, or stage. On the basis of quantitative image analysis, we confirm that ER expression in NBR increases with age in women with breast cancer, and report for the first time, a significant association between ER expression in NBR with ER-negative and triple-negative cancers in postmenopausal women.

  11. Skeletal Muscle Estrogen Receptor Activation in Response to Eccentric Exercise Up-Regulates Myogenic-Related Gene Expression Independent of Differing Serum Estradiol Levels Occurring during the Human Menstrual Cycle.

    Science.gov (United States)

    Haines, Mackenzie; McKinley-Barnard, Sarah K; Andre, Thomas L; Gann, Josh J; Hwang, Paul S; Willoughby, Darryn S

    2018-03-01

    This study sought to determine if the differences in serum estradiol we have previously observed to occur during the mid-follicular (MF) and mid-luteal (ML) phases of the female menstrual cycle could be attributed to estrogen-induced receptor activation and subsequent effects on myogenic-related genes which may otherwise impact muscle regeneration in response to eccentric exercise. Twenty-two physically-active females (20.9 ± 1.4 years, 63.5 ± 9.0 kg, 1.65 ± 0.08 m) underwent an eccentric exercise bout of the knee extensors during the MF and ML phases of their 28-day menstrual cycle. Prior to (PRE), at 6 (6HRPOST), and 24 (24HRPOST) hours post-exercise for each session, participants had muscle biopsies obtained. Skeletal muscle estradiol and estrogen receptor-α (ER-α) content and ER-DNA binding were determined with ELISA. Real-time PCR was used to assess ER-α, Myo-D, and cyclin D1 mRNA expression. Data were analyzed utilizing a 2 x 3 repeated measures univariate analyses of variance (ANOVA) for each criterion variable (p ≤ .05). Skeletal muscle estradiol levels were not significantly impacted by either menstrual phase (p > 0.05); however, both ER-α mRNA and protein were significantly increased during MF (p < 0.05). ER-DNA binding and Myo-D mRNA expression increased significantly in both menstrual phases in response to exercise but were not different from one another; however, cyclin D1 mRNA expression was significantly greater during MF. This study demonstrates that skeletal muscle ER-α activation in response to eccentric exercise up-regulates myogenic-related gene expression independent of serum estradiol levels occurring during the human menstrual cycle.

  12. Synthesis of 125I Labeled Estradiol-17-Hemisuccinate and Its Binding Study to Estrogen Receptors Using Scintillation Proximity Assay Method

    Directory of Open Access Journals (Sweden)

    Y. Susilo

    2012-12-01

    Full Text Available Research was carried out to obtain a selective ligand which strongly bind to estrogen receptors through determination of binding affinity of estradiol-17β-hemisuccinate. Selectivity of these compounds for estrogen receptor was studied using Scintillation Proximity Assay (SPA method. Primary reagents required in the SPA method including radioligand and receptor, the former was obtained by labeling of estradiol-17β-hemisuccinate with 125I, while MCF7 was used as the receptor. The labeling process was performed by indirect method via two-stage reaction. In this procedure, first step was activation of estradiol-17β-hemisuccinate using isobutylchloroformate and tributylamine as a catalist, while labeling of histamine with 125I was carried out using chloramin-T method to produce 125I-histamine. The second stage was conjugation of activated estradiol-17β-hemisuccinate with 125I-histamine. The product of estradiol-17β-hemisuccinate labeled 125I was extracted using toluene. Furtherly, the organic layer was purified by TLC system. Characterization of estradiol-17β-hemisuccinate labeled 125I from this solvent extraction was carried out by determining its radiochemical purity and the result was obtained using paper electrophoresis and TLC were 79.8% and 84.4% respectively. Radiochemical purity could be increased when purification step was repeated using TLC system, the result showed up to 97.8%. Determination of binding affinity by the SPA method was carried out using MCF7 cell lines which express estrogen receptors showed the value of Kd at 7.192 x 10-3 nM and maximum binding at 336.1 nM. This low value of Kd indicated that binding affinity of estradiol-17β-hemisuccinate was high or strongly binds to estrogen recepto

  13. Effects of repeated 9 and 30-day exposure to extremely low-frequency electromagnetic fields on social recognition behavior and estrogen receptors expression in olfactory bulb of Wistar female rats.

    Science.gov (United States)

    Bernal-Mondragón, C; Arriaga-Avila, V; Martínez-Abundis, E; Barrera-Mera, B; Mercado-Gómez, O; Guevara-Guzmán, R

    2017-02-01

    We investigated the short- and long-term effects of extremely low-frequency electromagnetic fields (EMF) on social recognition behavior and expression of α- and β-estrogen receptors (ER). Rats were exposed to 60-Hz electromagnetic fields for 9 or 30 days and tested for social recognition behavior. Immunohistochemistry and western blot assays were performed to evaluate α- and β-ER expression in the olfactory bulb of intact, ovariectomized (OVX), and ovariectomized+estradiol (E2) replacement (OVX+E2). Ovariectomization showed impairment of social recognition after 9 days of EMF exposure and a complete recovery after E2 replacement and so did those after 30 days. Short EMF exposure increased expression of β-ER in intact, but not in the others. Longer exposure produced a decrease in intact but an increase in OVX and OVX+E2. Our findings suggest a significant role for β-estrogen receptors and a lack of effect for α-estrogen receptors on a social recognition task. EMF: extremely low frequency electromagnetic fields; ERs: estrogen receptors; OB: olfactory bulb; OVX: ovariectomized; OVX + E 2 : ovariectomized + estradiol replacement; IEI: interexposure interval; β-ER: beta estrogen receptor; E 2 : replacement of estradiol; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; WB: Western blot; PBS: phosphate-buffer saline; PB: phosphate-buffer.

  14. Central estrogenic pathways protect against the depressant action of acute nicotine on reflex tachycardia in female rats

    International Nuclear Information System (INIS)

    El-Mas, Mahmoud M.; Fouda, Mohamed A.; El-gowilly, Sahar M.; Saad, Evan I.

    2012-01-01

    We have previously shown that acute exposure of male rats to nicotine preferentially attenuates baroreceptor-mediated control of reflex tachycardia in contrast to no effect on reflex bradycardia. Here, we investigated whether female rats are as sensitive as their male counterparts to the baroreflex depressant effect of nicotine and whether this interaction is modulated by estrogen. Baroreflex curves relating reflex chronotropic responses evoked by i.v. doses (1–16 μg/kg) of phenylephrine (PE) or sodium nitroprusside (SNP), were constructed in conscious freely moving proestrus, ovariectomized (OVX), and estrogen (50 μg/kg/day s.c., 5 days)-replaced OVX (OVXE 2 ) rats. Slopes of the curves were taken as a measure of baroreflex sensitivity (BRS PE and BRS SNP ). Nicotine (100 μg/kg i.v.) reduced BRS SNP in OVX rats but not in proestrus or OVXE 2 rats. The attenuation of reflex tachycardia by nicotine was also evident in diestrus rats, which exhibited plasma estrogen levels similar to those of OVX rats. BRS PE was not affected by nicotine in all rat preparations. Experiments were then extended to determine whether central estrogenic receptors modulate the nicotine–BRS SNP interaction. Intracisteral (i.c.) treatment of OVX rats with estrogen sulfate (0.2 μg/rat) abolished the BRS SNP attenuating effect of i.v. nicotine. This protective effect of estrogen disappeared when OVX rats were pretreated with i.c. ICI 182,780 (50 μg/rat, selective estrogen receptor antagonist). Together, these findings suggest that central neural pools of estrogen receptors underlie the protection offered by E 2 against nicotine-induced baroreceptor dysfunction in female rats. -- Highlights: ► Estrogen protects against the depressant effect of nicotine on reflex tachycardia. ► The baroreflex response and estrogen status affect the nicotine–BRS interaction. ► The protection offered by estrogen is mediated via central estrogen receptors.

  15. In silico study of curcumol, curcumenol, isocurcumenol, and β-sitosterol as potential inhibitors of estrogen receptor alpha of breast cancer

    Directory of Open Access Journals (Sweden)

    Resmi Mustarichiei

    2014-03-01

    Full Text Available Background: Based on data from the Hospital Information System (HIS in 2007, breast cancer is the top ranked diagnosed cancer in Indonesia. Estrogen receptor alpha (ERα is associated with breast cancer because it is found in high levels in cancer tissues. Curcumol, curcumenol, isocurcumenol of white tumeric rhizomes (Curcuma zedoaria (Christm. Roscoe, and β-sitosterol from seeds of pumpkin (Cucurbita pepo L. have been reported to have inhibitory activity against cancer cells. This study presents the in silico study of these compounds as inhibitors of ERα.Methods: Docking simulations are carried out in this paper to visualize molecular-level interactions between the four compounds with ERα. Docking simulations between estradiol and tamoxifen on ERα are carried out as well.Results: Docking results indicated that curcumol, curcumenol, isocurcumenol, and β-sitosterol showed inhibitory activity againts estrogen receptor alpha (ERα.  The order of potency is shown consecutively by isocurcumenol, curcumol, curcumenol, and β-sitosterol with values 0.584 M, 1.36 M, 1.61 M, and 7.35 M respectively. Curcumenol and estradiol interacts with ERα through hydrogen bonds and hydrophobic interactions, whereas curcumol, isocurcumenol, β-sitosterol and tamoxifen through hydrophobic interactions in succession. Conclusion: Natural products containing all four compounds have the potential to be used as drugs or adjuvant drugs in breast cancer therapy.Keywords: β-sitosterol, breast cancer, curcumol, curcumenol, estradiol, ERα, isocurcumenol

  16. Ligand Binding Affinities of Arctigenin and Its Demethylated Metabolites to Estrogen Receptor Alpha

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    Masao Hattori

    2013-01-01

    Full Text Available Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (−-arctigenin, the aglycone of arctiin, was demethylated to (−-dihydroxyenterolactone (DHENL by Eubacterium (E. sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (−-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (−-arctigenin using a ligand binding screen assay method. The IC50 value of (2R,3R-2-(4-hydroxy-3-methoxybenzyl-3-(3,4-dihydroxybenzyl-butyrolactone was 7.9 × 10−4 M.

  17. Estrogen receptor (ESR1) mRNA expression and benefit from tamoxifen in the treatment and prevention of estrogen receptor-positive breast cancer.

    Science.gov (United States)

    Kim, Chungyeul; Tang, Gong; Pogue-Geile, Katherine L; Costantino, Joseph P; Baehner, Frederick L; Baker, Joffre; Cronin, Maureen T; Watson, Drew; Shak, Steven; Bohn, Olga L; Fumagalli, Debora; Taniyama, Yusuke; Lee, Ahwon; Reilly, Megan L; Vogel, Victor G; McCaskill-Stevens, Worta; Ford, Leslie G; Geyer, Charles E; Wickerham, D Lawrence; Wolmark, Norman; Paik, Soonmyung

    2011-11-01

    Several mechanisms have been proposed to explain tamoxifen resistance of estrogen receptor (ER) -positive tumors, but a clinically useful explanation for such resistance has not been described. Because the ER is the treatment target for tamoxifen, a linear association between ER expression levels and the degree of benefit from tamoxifen might be expected. However, such an association has never been demonstrated with conventional clinical ER assays, and the ER is currently used clinically as a dichotomous marker. We used gene expression profiling and ER protein assays to help elucidate molecular mechanism(s) responsible for tamoxifen resistance in breast tumors. We performed gene expression profiling of paraffin-embedded tumors from National Surgical Adjuvant Breast and Bowel Project (NSABP) trials that tested the worth of tamoxifen as an adjuvant systemic therapy (B-14) and as a preventive agent (P-1). This was a retrospective subset analysis based on available materials. In B-14, ESR1 was the strongest linear predictor of tamoxifen benefit among 16 genes examined, including PGR and ERBB2. On the basis of these data, we hypothesized that, in the P-1 trial, a lower level of ESR1 mRNA in the tamoxifen arm was the main difference between the two study arms. Only ESR1 was downregulated by more than two-fold in ER-positive cancer events in the tamoxifen arm (P < .001). Tamoxifen did not prevent ER-positive tumors with low levels of ESR1 expression. These data suggest that low-level expression of ESR1 is a determinant of tamoxifen resistance in ER-positive breast cancer. Strategies should be developed to identify, treat, and prevent such tumors.

  18. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Directory of Open Access Journals (Sweden)

    Niu AQ

    2016-07-01

    Full Text Available Ai-qin Niu,1 Liang-jun Xie,2 Hui Wang,1 Bing Zhu,1 Sheng-qi Wang3 1Department of Gynecology, the First People’s Hospital of Shangqiu, Shangqiu, Henan, People’s Republic of China; 2Department of Image Diagnoses, the Third Hospital of Jinan, Jinan, Shandong, People’s Republic of China; 3Department of Mammary Disease, Guangdong Provincial Hospital of Chinese Medicine, the Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China Background: Estrogen receptors (ERs are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. Methods: Herein, we focused on ER-β and developed its in silico quantitative structure-activity relationship models using machine learning (ML methods. Results: The chemical structures and ER-β bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior

  19. Induction of osteoblast differentiation by selective activation of kinase-mediated actions of the estrogen receptor.

    Science.gov (United States)

    Kousteni, Stavroula; Almeida, Maria; Han, Li; Bellido, Teresita; Jilka, Robert L; Manolagas, Stavros C

    2007-02-01

    Estrogens control gene transcription by cis or trans interactions of the estrogen receptor (ER) with target DNA or via the activation of cytoplasmic kinases. We report that selective activation of kinase-mediated actions of the ER with 4-estren-3alpha,17beta-diol (estren) or an estradiol-dendrimer conjugate, each a synthetic compound that stimulates kinase-mediated ER actions 1,000 to 10,000 times more potently than direct DNA interactions, induced osteoblastic differentiation in established cell lines of uncommitted osteoblast precursors and primary cultures of osteoblast progenitors by stimulating Wnt and BMP-2 signaling in a kinase-dependent manner. In sharp contrast, 17beta-estradiol (E(2)) suppressed BMP-2-induced osteoblast progenitor commitment and differentiation. Consistent with the in vitro findings, estren, but not E(2), stimulated Wnt/beta-catenin-mediated transcription in T-cell factor-lacZ transgenic mice. Moreover, E(2) stimulated BMP signaling in mice in which ERalpha lacks DNA binding activity and classical estrogen response element-mediated transcription (ERalpha(NERKI/-)) but not in wild-type controls. This evidence reveals for the first time the existence of a large signalosome in which inputs from the ER, kinases, bone morphogenetic proteins, and Wnt signaling converge to induce differentiation of osteoblast precursors. ER can either induce it or repress it, depending on whether the activating ligand (and presumably the resulting conformation of the receptor protein) precludes or accommodates ERE-mediated transcription.

  20. Impact of estradiol, estrogen receptor subtype-selective agonists and genistein on energy homeostasis

    OpenAIRE

    Weigt, Carmen

    2013-01-01

    The prevalence of obesity is dramatically increasing and thus constitutes a major risk factor for developing chronic diseases such as type 2 diabetes, dyslipidemia, cardiovascular diseases, and certain forms of cancer. High-caloric nutrition and a lack of physical activity are the main contributing factors for this global epidemic. Estrogen receptors (ERs) are recognized to be involved in many processes related to the control of energy homeostasis. In my studies, I investigated the impac...

  1. Estrogens and cognition: Friends or foes?: An evaluation of the opposing effects of estrogens on learning and memory.

    Science.gov (United States)

    Korol, Donna L; Pisani, Samantha L

    2015-08-01

    This article is part of a Special Issue "Estradiol and cognition". Estrogens are becoming well known for their robust enhancement on cognition particularly for learning and memory that relies upon functioning of the hippocampus and related neural systems. What is also emerging is that estrogen modulation of cognition is not uniform, at times enhancing yet at other times impairing learning. This review explores the bidirectional effects of estrogens on learning from a multiple memory systems view, focusing on the hippocampus and striatum, whereby modulation by estrogens sorts according to task attributes and neural systems engaged during cognition. We highlight our findings showing that the ability to solve hippocampus-sensitive tasks typically improves under relatively high estrogen status while the ability to solve striatum-sensitive tasks degrades with estrogen exposures. Though constrained by dose and timing of exposure, these opposing enhancements and impairments of cognition can be observed following treatments with different estrogenic compounds including the hormone estradiol, the isoflavone genistein found in soybeans, and agonists that are selective for specific estrogen receptors, suggesting that activation of a single receptor type is sufficient to produce the observed shifts in learning strategies. Using this multi-dimensional framework will allow us to extend our thinking of the relationship between estrogens and cognition to other brain regions and cognitive functions. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. In situ aromatase expression in primary tumor is associated with estrogen receptor expression but is not predictive of response to endocrine therapy in advanced breast cancer

    International Nuclear Information System (INIS)

    Lykkesfeldt, Anne E; Henriksen, Katrine L; Rasmussen, Birgitte B; Sasano, Hironobu; Evans, Dean B; Møller, Susanne; Ejlertsen, Bent; Mouridsen, Henning T

    2009-01-01

    New, third-generation aromatase inhibitors (AIs) have proven comparable or superior to the anti-estrogen tamoxifen for treatment of estrogen receptor (ER) and/or progesterone receptor (PR) positive breast cancer. AIs suppress total body and intratumoral estrogen levels. It is unclear whether in situ carcinoma cell aromatization is the primary source of estrogen production for tumor growth and whether the aromatase expression is predictive of response to endocrine therapy. Due to methodological difficulties in the determination of the aromatase protein, COX-2, an enzyme involved in the synthesis of aromatase, has been suggested as a surrogate marker for aromatase expression. Primary tumor material was retrospectively collected from 88 patients who participated in a randomized clinical trial comparing the AI letrozole to the anti-estrogen tamoxifen for first-line treatment of advanced breast cancer. Semi-quantitative immunohistochemical (IHC) analysis was performed for ER, PR, COX-2 and aromatase using Tissue Microarrays (TMAs). Aromatase was also analyzed using whole sections (WS). Kappa analysis was applied to compare association of protein expression levels. Univariate Wilcoxon analysis and the Cox-analysis were performed to evaluate time to progression (TTP) in relation to marker expression. Aromatase expression was associated with ER, but not with PR or COX-2 expression in carcinoma cells. Measurements of aromatase in WS were not comparable to results from TMAs. Expression of COX-2 and aromatase did not predict response to endocrine therapy. Aromatase in combination with high PR expression may select letrozole treated patients with a longer TTP. TMAs are not suitable for IHC analysis of in situ aromatase expression and we did not find COX-2 expression in carcinoma cells to be a surrogate marker for aromatase. In situ aromatase expression in tumor cells is associated with ER expression and may thus point towards good prognosis. Aromatase expression in cancer

  3. Estrogen-related receptor α decreases RHOA stability to induce orientated cell migration.

    Science.gov (United States)

    Sailland, Juliette; Tribollet, Violaine; Forcet, Christelle; Billon, Cyrielle; Barenton, Bruno; Carnesecchi, Julie; Bachmann, Alice; Gauthier, Karine Cécile; Yu, Shan; Giguère, Vincent; Chan, Franky L; Vanacker, Jean-Marc

    2014-10-21

    Several physiopathological processes require orientated cellular migration. This phenomenon highly depends on members of the RHO family of GTPases. Both excessive and deficient RHO activity impair directional migration. A tight control is thus exerted on these proteins through the regulation of their activation and of their stability. Here we show that the estrogen-related receptor α (ERRα) directly activates the expression of TNFAIP1, the product of which [BTB/POZ domain-containing adapter for Cullin3-mediated RhoA degradation 2 (BACURD2)] regulates RHOA protein turnover. Inactivation of the receptor leads to enhanced RHOA stability and activation. This results in cell disorientation, increased actin network, and inability to form a lamellipodium at the migration edge. As a consequence, directional migration, but not cell motility per se, is impaired in the absence of the receptor, under pathological as well as physiological conditions. Altogether, our results show that the control exerted by ERRα on RHOA stability is required for directional migration.

  4. Ovarian steroids regulate tachykinin and tachykinin receptor gene expression in the mouse uterus

    Directory of Open Access Journals (Sweden)

    Patak Eva

    2009-07-01

    Full Text Available Abstract Background In the mouse uterus, pregnancy is accompanied by changes in tachykinin and tachykinin receptor gene expression and in the uterotonic effects of endogenous tachykinins. In this study we have investigated whether changes in tachykinin expression and responses are a result of changes in ovarian steroid levels. Methods We quantified the mRNAs of tachykinins and tachykinin receptors in uteri from ovariectomized mice and studied their regulation in response to estrogen and progesterone using real-time quantitative RT-PCR. Early (3 h and late (24 h responses to estrogen were evaluated and the participation of the estrogen receptors (ER, ERalpha and ERbeta, was analyzed by treating mice with propylpyrazole triol, a selective ERalpha agonist, or diarylpropionitrile, a selective agonist of ERbeta. Results All genes encoding tachykinins (Tac1, Tac2 and Tac4 and tachykinin receptors (Tacr1, Tacr2 and Tacr3 were expressed in uteri from ovariectomized mice. Estrogen increased Tac1 and Tacr1 mRNA after 3 h and decreased Tac1 and Tac4 expression after 24 h. Tac2 and Tacr3 mRNA levels were decreased by estrogen at both 3 and 24 h. Most effects of estrogen were also observed in animals treated with propylpyrazole triol. Progesterone treatment increased the levels of Tac2. Conclusion These results show that the expression of tachykinins and their receptors in the mouse uterus is tightly and differentially regulated by ovarian steroids. Estrogen effects are mainly mediated by ERalpha supporting an essential role for this estrogen receptor in the regulation of the tachykinergic system in the mouse uterus.

  5. Estrogen receptor alpha/beta ratio and estrogen receptor beta as predictors of endocrine therapy responsiveness–a randomized neoadjuvant trial comparison between anastrozole and tamoxifen for the treatment of postmenopausal breast cancer

    International Nuclear Information System (INIS)

    Madeira, Marcelo; Mattar, André; Logullo, Ângela Flávia; Soares, Fernando Augusto; Gebrim, Luiz Henrique

    2013-01-01

    The role of estrogen receptor beta (ER-β) in breast cancer (BC) remains unclear. Some studies have suggested that ER-β may oppose the actions of estrogen receptor alpha (ER-α), and clinical evidence has indicated that the loss of ER-β expression is associated with a poor prognosis and resistance to endocrine therapy. The objective of the present study was to determine the role of ER-β and the ER-α/ER-β ratio in predicting the response to endocrine therapy and whether different regimens have any effect on ER-β expression levels. Ninety postmenopausal patients with primary BC were recruited for a short-term double-blinded randomized prospective controlled study. To determine tumor cell proliferation, we measured the expression of Ki67 in tumor biopsy samples taken before and after 26 days of treatment with anastrozole 1 mg/day (N = 25), tamoxifen 20 mg/day (N = 24) or placebo (N = 29) of 78 participants. The pre- and post-samples were placed in tissue microarray blocks and submitted for immunohistochemical assay. Biomarker statuses (ER-β, ER-α and Ki67) were obtained by comparing each immunohistochemical evaluation of the pre- and post-surgery samples using the semi-quantitative Allred’s method. Statistical analyses were performed using an ANOVA and Spearman’s correlation coefficient tests, with significance at p ≤ 0.05. The frequency of ER-β expression did not change after treatment (p = 0.33). There were no significant changes in Ki67 levels in ER-β-negative cases (p = 0.45), but in the ER-β-positive cases, the anastrozole (p = 0.01) and tamoxifen groups (p = 0.04) presented a significant reduction in post-treatment Ki67 scores. There was a weak but positive correlation between the ER-α and ER-β expression levels. Only patients with an ER-α/ER-β expression ratio between 1 and 1.5 demonstrated significant differences in Ki67 levels after treatment with anastrozole (p = 0.005) and tamoxifen (p = 0.026). Our results provide additional data that

  6. Quantum chemical studies of estrogenic compounds

    Science.gov (United States)

    Quantum chemical methods are potent tools to provide information on the chemical structure and electronic properties of organic molecules. Modern computational chemistry methods have provided a great deal of insight into the binding of estrogenic compounds to estrogenic receptors (ER), an important ...

  7. Inhibition of aryl hydrocarbon receptor-dependent transcription by resveratrol or kaempferol is independent of estrogen receptor α expression in human breast cancer cells

    Science.gov (United States)

    MacPherson, Laura; Matthews, Jason

    2016-01-01

    Resveratrol and kaempferol are natural chemopreventative agents that are also aryl hydrocarbon receptor (AHR) antagonists and estrogen receptor (ER) agonists. In this study we evaluated the role of ERα in resveratrol- and kaempferol-mediated inhibition of AHR-dependent transcription. Kaempferol or resveratrol inhibited dioxin-induced cytochrome P450 1A1 (CYP1A1) and CYP1B1 expression levels and recruitment of AHR, ERα and co-activators to CYP1A1 and CYP1B1. Both phytochemicals induced the expression and recruitment of ERα to gene amplified in breast cancer 1 (GREB1). RNAi-mediated knockdown of ERα in T-47D cells did not affect the inhibitory action of either phytochemical on AHR activity. Both compounds also inhibited AHR-dependent transcription in ERα-negative MDA-MB-231 and BT-549 breast cancer cells. These data show that ERα does not contribute to the AHR-inhibitory activities of resveratrol and kaempferol. PMID:20846786

  8. Estrogen receptor positive breast tumors resist chemotherapy by the overexpression of P53 in Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Fatma Ashour

    2018-06-01

    Full Text Available Background and Objectives: Breast cancer (BC is classified according to estrogen receptor (ER status into ER+ and ER− tumors. ER+ tumors have a worse response to chemotherapy compared to ER− tumors. BCL-2, TP53, BAX and NF-ΚB are involved in drug resistance in the ER+ tumors. Recently it was shown that Cancer Stem Cells (CSCs play an important role in drug resistance. In this study we tested the hypothesis that CSCs of the ER+ tumors resist drug through the overexpression of BCL-2, TP53, BAX and NF-ΚB. Methods: CSCs were isolated by anoikis resistance assay from MCF7 (ER+ and MDA-MB-231 (ER− cell lines. Isolated CSCs were treated with doxorubicin (DOX and the mRNA expression levels of BCL-2, TP53, BAX and NFKB were investigated by quantitative real time PCR (qPCR with and without treatment. Results: BCL-2, BAX and NF-ΚB showed decreased expression in MCF7 bulk cancer cells after DOX treatment whereas only BCL-2 and BAX showed decreased expression in MDA-MB-231 bulk cancer cells. Interestingly TP53 was the only gene showed a considerable increase in its expression in CSCs of the ER+ MCF7 cell line compared to bulk cancer cells. Moreover, TP53 was the only gene showing exceptionally higher level of expression in MCF7-CSCs compared to MDA-MB-231-CSCs. Conclusion: Our results suggest that CSCs in the ER+ cells escape the effect of DOX treatment by the elevation of p53 expression. Keywords: Breast cancer, Cancer Stem Cells, Drug resistance, Estrogen receptors

  9. Selective estrogen receptor modulator promotes weight loss in ovariectomized female rhesus monkeys (Macaca mulatta) by decreasing food intake and increasing activity.

    Science.gov (United States)

    Sullivan, Elinor L; Shearin, Jean; Koegler, Frank H; Cameron, Judy L

    2012-04-01

    The effect of hormone replacement therapy (HRT) on body weight in postmenopausal women is controversial, with studies reporting an increase, a decrease, and no change in body weight. To examine estrogen receptor actions on body weight, we investigated the effects of treatment with a selective estrogen receptor modulator (SERM) on body weight, food intake, and activity and metabolic rate in a nonhuman primate model. Eighteen ovariectomized female rhesus monkeys were treated with a nonsteroidal SERM (GSK232802A, 5 mg/kg po) for 3 mo. GSK232802A decreased lutenizing hormone (P Physical activity increased during the 3rd mo of treatment (P = 0.04). Baseline activity level and the change in activity due to treatment were correlated, with the most sedentary individuals exhibiting increased physical activity during the 1st mo of treatment (P = 0.02). Metabolic rate did not change (P = 0.58). These results indicate that GSK232802A treatment reduces body weight and adiposity in ovariectomized nonhuman primates by suppressing food intake and increasing activity, particularly in the most sedentary individuals. These findings suggest that SERM treatment may counteract weight gain in postmenopausal women.

  10. Computational method for discovery of estrogen responsive genes

    DEFF Research Database (Denmark)

    Tang, Suisheng; Tan, Sin Lam; Ramadoss, Suresh Kumar

    2004-01-01

    Estrogen has a profound impact on human physiology and affects numerous genes. The classical estrogen reaction is mediated by its receptors (ERs), which bind to the estrogen response elements (EREs) in target gene's promoter region. Due to tedious and expensive experiments, a limited number of hu...

  11. Possible Estrogen Dependency in the Pathogenesis of Branchial Cleft Cysts

    Directory of Open Access Journals (Sweden)

    Jan D. Raguse

    2017-01-01

    Full Text Available Background. Even though branchial cleft cysts are currently accepted as a congenital anomaly, there is often a long delay until clinical presentation; branchial cleft cysts classically appear in the second to fourth decade of life. Our observation of their occurrence in three pregnant women encouraged us to contemplate a possible hormonal influence. Methods. Immunohistological analysis was performed for the evaluation of the estrogen receptor alpha (ERα in paraffin-embedded tissue specimens of 16 patients with a diagnosis of branchial cleft cyst, with three of them being pregnant. Results. Expression of ERα was detected within epithelial cells only in branchial cleft cysts in pregnant females; moreover, higher growth fractions (Ki-67/Mib1 were found. Conclusion. The fact that the estrogen receptor was expressed only in pregnant women, in contrast to 13 investigated cases, may suggest that the high level of estrogen in pregnancy is a possible explanation for the spontaneous growth of branchial cleft cysts.

  12. Possible Estrogen Dependency in the Pathogenesis of Branchial Cleft Cysts.

    Science.gov (United States)

    Raguse, Jan D; Anagnostopoulos, Ioannis; Doll, Christian; Heiland, Max; Jöhrens, Korinna

    2017-01-01

    Even though branchial cleft cysts are currently accepted as a congenital anomaly, there is often a long delay until clinical presentation; branchial cleft cysts classically appear in the second to fourth decade of life. Our observation of their occurrence in three pregnant women encouraged us to contemplate a possible hormonal influence. Immunohistological analysis was performed for the evaluation of the estrogen receptor alpha (ER α ) in paraffin-embedded tissue specimens of 16 patients with a diagnosis of branchial cleft cyst, with three of them being pregnant. Expression of ER α was detected within epithelial cells only in branchial cleft cysts in pregnant females; moreover, higher growth fractions (Ki-67/Mib1) were found. The fact that the estrogen receptor was expressed only in pregnant women, in contrast to 13 investigated cases, may suggest that the high level of estrogen in pregnancy is a possible explanation for the spontaneous growth of branchial cleft cysts.

  13. WNT4 mediates estrogen receptor signaling and endocrine resistance in invasive lobular carcinoma cell lines.

    Science.gov (United States)

    Sikora, Matthew J; Jacobsen, Britta M; Levine, Kevin; Chen, Jian; Davidson, Nancy E; Lee, Adrian V; Alexander, Caroline M; Oesterreich, Steffi

    2016-09-20

    Invasive lobular carcinoma (ILC) of the breast typically presents with clinical biomarkers consistent with a favorable response to endocrine therapies, and over 90 % of ILC cases express the estrogen receptor (ER). However, a subset of ILC cases may be resistant to endocrine therapies, suggesting that ER biology is unique in ILC. Using ILC cell lines, we previously demonstrated that ER regulates a distinct gene expression program in ILC cells, and we hypothesized that these ER-driven pathways modulate the endocrine response in ILC. One potential novel pathway is via the Wnt ligand WNT4, a critical signaling molecule in mammary gland development regulated by the progesterone receptor. The ILC cell lines MDA-MB-134-VI, SUM44PE, and BCK4 were used to assess WNT4 gene expression and regulation, as well as the role of WNT4 in estrogen-regulated proliferation. To assess these mechanisms in the context of endocrine resistance, we developed novel ILC endocrine-resistant long-term estrogen-deprived (ILC-LTED) models. ILC and ILC-LTED cell lines were used to identify upstream regulators and downstream signaling effectors of WNT4 signaling. ILC cells co-opted WNT4 signaling by placing it under direct ER control. We observed that ER regulation of WNT4 correlated with use of an ER binding site at the WNT4 locus, specifically in ILC cells. Further, WNT4 was required for endocrine response in ILC cells, as WNT4 knockdown blocked estrogen-induced proliferation. ILC-LTED cells remained dependent on WNT4 for proliferation, by either maintaining ER function and WNT4 regulation or uncoupling WNT4 from ER and upregulating WNT4 expression. In the latter case, WNT4 expression was driven by activated nuclear factor kappa-B signaling in ILC-LTED cells. In ILC and ILC-LTED cells, WNT4 led to suppression of CDKN1A/p21, which is critical for ILC cell proliferation. CDKN1A knockdown partially reversed the effects of WNT4 knockdown. WNT4 drives a novel signaling pathway in ILC cells, with a

  14. Deep Learning Accurately Predicts Estrogen Receptor Status in Breast Cancer Metabolomics Data.

    Science.gov (United States)

    Alakwaa, Fadhl M; Chaudhary, Kumardeep; Garmire, Lana X

    2018-01-05

    Metabolomics holds the promise as a new technology to diagnose highly heterogeneous diseases. Conventionally, metabolomics data analysis for diagnosis is done using various statistical and machine learning based classification methods. However, it remains unknown if deep neural network, a class of increasingly popular machine learning methods, is suitable to classify metabolomics data. Here we use a cohort of 271 breast cancer tissues, 204 positive estrogen receptor (ER+), and 67 negative estrogen receptor (ER-) to test the accuracies of feed-forward networks, a deep learning (DL) framework, as well as six widely used machine learning models, namely random forest (RF), support vector machines (SVM), recursive partitioning and regression trees (RPART), linear discriminant analysis (LDA), prediction analysis for microarrays (PAM), and generalized boosted models (GBM). DL framework has the highest area under the curve (AUC) of 0.93 in classifying ER+/ER- patients, compared to the other six machine learning algorithms. Furthermore, the biological interpretation of the first hidden layer reveals eight commonly enriched significant metabolomics pathways (adjusted P-value learning methods. Among them, protein digestion and absorption and ATP-binding cassette (ABC) transporters pathways are also confirmed in integrated analysis between metabolomics and gene expression data in these samples. In summary, deep learning method shows advantages for metabolomics based breast cancer ER status classification, with both the highest prediction accuracy (AUC = 0.93) and better revelation of disease biology. We encourage the adoption of feed-forward networks based deep learning method in the metabolomics research community for classification.

  15. Cell surface estrogen receptor alpha is upregulated during subchronic metabolic stress and inhibits neuronal cell degeneration.

    Directory of Open Access Journals (Sweden)

    Cristiana Barbati

    Full Text Available In addition to the classical nuclear estrogen receptor, the expression of non-nuclear estrogen receptors localized to the cell surface membrane (mER has recently been demonstrated. Estrogen and its receptors have been implicated in the development or progression of numerous neurodegenerative disorders. Furthermore, the pathogenesis of these diseases has been associated with disturbances of two key cellular programs: apoptosis and autophagy. An excess of apoptosis or a defect in autophagy has been implicated in neurodegeneration. The aim of this study was to clarify the role of ER in determining neuronal cell fate and the possible implication of these receptors in regulating either apoptosis or autophagy. The human neuronal cell line SH-SY5Y and mouse neuronal cells in primary culture were thus exposed to chronic minimal peroxide treatment (CMP, a form of subcytotoxic minimal chronic stress previously that mimics multiple aspects of long-term cell stress and represents a limited molecular proxy for neurodegenerative processes. We actually found that either E2 or E2-bovine serum albumin construct (E2BSA, i.e. a non-permeant form of E2 was capable of modulating intracellular cell signals and regulating cell survival and death. In particular, under CMP, the up-regulation of mERα, but not mERβ, was associated with functional signals (ERK phosphorylation and p38 dephosphorylation compatible with autophagic cytoprotection triggering and leading to cell survival. The mERα trafficking appeared to be independent of the microfilament system cytoskeletal network but was seemingly associated with microtubular apparatus network, i.e., to MAP2 molecular chaperone. Importantly, antioxidant treatments, administration of siRNA to ERα, or the presence of antagonist of ERα hindered these events. These results support that the surface expression of mERα plays a pivotal role in determining cell fate, and that ligand-induced activation of mER signalling exerts a

  16. Prognostic and predictive importance of the estrogen receptor coactivator AIB1 in a randomized trial comparing adjuvant letrozole and tamoxifen therapy in postmenopausal breast cancer

    DEFF Research Database (Denmark)

    Alkner, S; Jensen, Maj-Britt Raaby; Rasmussen, B B

    2017-01-01

    PURPOSE: To evaluate the estrogen receptor coactivator amplified in breast cancer 1 (AIB1) as a prognostic marker, as well as a predictive marker for response to adjuvant tamoxifen and/or aromatase inhibitors, in early estrogen receptor-positive breast cancer. METHOD: AIB1 was analyzed...... with immunohistochemistry in tissue microarrays of the Danish subcohort (N = 1396) of the International Breast Cancer Study Group's trial BIG 1-98 (randomization between adjuvant tamoxifen versus letrozole versus the sequence of the two drugs). RESULTS: Forty-six percent of the tumors had a high AIB1 expression. In line...... with previous studies, AIB1 correlated to a more aggressive tumor-phenotype (HER2 amplification and a high malignancy grade). High AIB1 also correlated to higher estrogen receptor expression (80-100 vs. 1-79%), and ductal histological type. High AIB1 expression was associated with a poor disease-free survival...

  17. Establishment of estrogen receptor 1 (ESR1)-knockout medaka: ESR1 is dispensable for sexual development and reproduction in medaka, Oryzias latipes.

    Science.gov (United States)

    Tohyama, Saki; Ogino, Yukiko; Lange, Anke; Myosho, Taijun; Kobayashi, Tohru; Hirano, Yu; Yamada, Gen; Sato, Tomomi; Tatarazako, Norihisa; Tyler, Charles R; Iguchi, Taisen; Miyagawa, Shinichi

    2017-08-01

    Estrogens play fundamental roles in regulating reproductive activities and they act through estrogen receptor (ESR) in all vertebrates. Most vertebrates have two ESR subtypes (ESR1 and ESR2), whereas teleost fish have at least three (Esr1, Esr2a and Esr2b). Intricate functionalization has been suggested among the Esr subtypes, but to date, distinct roles of Esr have been characterized in only a limited number of species. Study of loss-of-function in animal models is a powerful tool for application to understanding vertebrate reproductive biology. In the current study, we established esr1 knockout (KO) medaka using a TALEN approach and examined the effects of Esr1 ablation. Unexpectedly, esr1 KO medaka did not show any significant defects in their gonadal development or in their sexual characteristics. Neither male or female esr1 KO medaka exhibited any significant changes in sexual differentiation or reproductive activity compared with wild type controls. Interestingly, however, estrogen-induced vitellogenin gene expression, an estrogen-responsive biomarker in fish, was limited in the liver of esr1 KO males. Our findings, in contrast to mammals, indicate that Esr1 is dispensable for normal development and reproduction in medaka. We thus provide an evidence for estrogen receptor functionalization between mammals and fish. Our findings will also benefit interpretation of studies into the toxicological effects of estrogenic chemicals in fish. © 2017 Japanese Society of Developmental Biologists.

  18. Interactions between the cytomegalovirus promoter and the estrogen response element: implications for design of estrogen-responsive reporter plasmids.

    Science.gov (United States)

    Derecka, K; Wang, C K; Flint, A P F

    2006-07-01

    We aimed to produce an estrogen-responsive reporter plasmid that would permit monitoring of estrogen receptor function in the uterus in vivo. The plasmid pBL-tk-CAT(+)ERE was induced by estrogen in bovine endometrial stromal cells. When the CAT gene was replaced by the secreted alkaline phosphatase SeAP, the resulting construct pBL-tk-SeAP(+)ERE remained estrogen responsive. However when the tk promoter was replaced by the cytomegalovirus (cmv) promoter, the resulting plasmid (pBL-cmv-SeAP(+)ERE) was not estrogen responsive. Inhibition of ERE function was not due to an effect in trans or due to lack of estrogen receptor. It was not due to an interaction between the cmv promoter and the SeAP gene. cmv promoter function was dependent on NF-kappaB, and mutagenesis in the NF-kappaB sites reduced basal reporter expression without imparting responsiveness to estrogen. A mutation in the TATA box also failed to impart estrogen responsiveness. Modeling of DNA accessibility indicated the ERE was inserted at a site accessible to transcription factors. We conclude that the cmv promoter inhibits ERE function in cis when the two sequences are located in the same construct, and that this effect does not involve an interaction between cmv and reporter gene, NF-kappaB sites or the TATA box, or DNA inaccessibility.

  19. The synthesis of tritium, carbon-14 and stable isotope labelled selective estrogen receptor degraders.

    Science.gov (United States)

    Bragg, Ryan A; Bushby, Nick; Ericsson, Cecilia; Kingston, Lee P; Ji, Hailong; Elmore, Charles S

    2016-09-01

    As part of a Medicinal Chemistry program aimed at developing an orally bioavailable selective estrogen receptor degrader, a number of tritium, carbon-14, and stable isotope labelled (E)-3-[4-(2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl)phenyl]prop-2-enoic acids were required. This paper discusses 5 synthetic approaches to this compound class. Copyright © 2016 John Wiley & Sons, Ltd.

  20. Estrogen receptor-immunoreactive neurons in the lumbosacral cord projecting to the periaqueductal gray in the ovariectomized female cat

    NARCIS (Netherlands)

    VanderHorst, Veronique G.J.M.; Meijer, Ellie; Schasfoor, Fabienne C.; Leeuwen, Fred W. van; Holstege, Gert

    1997-01-01

    The periaqueductal gray (FAG) plays a crucial role in reproductive behavior. The present study investigates whether lumbosacral FAG-projecting neurons contain estrogen receptors. In four ovariectomized adult female cats, injections with cholera toxin subunit (CTb) were made into the FAG to

  1. American Society of Clinical Oncology/College of American Pathologists guideline recommendations for immunohistochemical testing of estrogen and progesterone receptors in breast cancer (unabridged version).

    NARCIS (Netherlands)

    Hammond, M.E.; Hayes, D.F.; Dowsett, M.; Allred, D.C.; Hagerty, K.L.; Badve, S.; Fitzgibbons, P.L.; Francis, G.; Goldstein, N.S.; Hayes, M.; Hicks, D.G.; Lester, S.; Love, R.; Mangu, P.B.; McShane, L.; Miller, K.; Osborne, C.K.; Paik, S.; Perlmutter, J.; Rhodes, A.; Sasano, H.; Schwartz, J.N.; Sweep, F.C.; Taube, S.; Torlakovic, E.E.; Valenstein, P.; Viale, G.; Visscher, D.; Wheeler, T.; Williams, R.B.; Wittliff, J.L.; Wolff, A.C.

    2010-01-01

    PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of

  2. Combined Effects of Circulating Levels of 25-Hydroxyvitamin D and Th1 and Th2 Cytokines on Breast Cancer Estrogen Receptor Status

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Song, E-mail: song.yao@roswellpark.org; Hong, Chi-Chen; McCann, Susan E.; Zirpoli, Gary; Quan, Lei; Gong, Zhihong [Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY 14263 (United States); Johnson, Candace S. [Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY 14263 (United States); Trump, Donald L. [Department of Medicine, Roswell Park Cancer Institute, Buffalo, NY 14263 (United States); Ambrosone, Christine B. [Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY 14263 (United States)

    2014-01-27

    Vitamin D has been recognized for its immune-modulating properties. We have previously found that levels of 25OHD, and cytokines including IL5, IFNα2, and TNFα, are also associated with estrogen receptor (ER) negative breast cancer in younger women. Thus, we hypothesized that there may be interactions between vitamin D and the immune system in influencing breast cancer ER status, which was tested in 490 women with incident breast cancer. There was no correlation of the levels of 25OHD with any cytokine, and their associations with tumor ER negative status were independent of each other. However, premenopausal women with low 25OHD and high TNFα levels had the highest likelihood of having ER negative cancer (odds ratio [OR] = 7.32, 95% confidence interval [CI] = 2.44−21.98), with evidence of synergy between the two (relative excess risk due to interaction [RERI] = 5.46, p for additive interaction = 0.14, and p for multiplicative interaction = 0.09). There were similar synergistic associations between 25OHD and IL5, and several IFNα2 to Th2 cytokine ratios. This is the first study to provide evidence of interactions between vitamin D and the immune system in relation to breast cancer ER status, which may inform combinational use of vitamin D and anti-inflammatory drugs for cancer prevention and therapy.

  3. Combined Effects of Circulating Levels of 25-Hydroxyvitamin D and Th1 and Th2 Cytokines on Breast Cancer Estrogen Receptor Status

    International Nuclear Information System (INIS)

    Yao, Song; Hong, Chi-Chen; McCann, Susan E.; Zirpoli, Gary; Quan, Lei; Gong, Zhihong; Johnson, Candace S.; Trump, Donald L.; Ambrosone, Christine B.

    2014-01-01

    Vitamin D has been recognized for its immune-modulating properties. We have previously found that levels of 25OHD, and cytokines including IL5, IFNα2, and TNFα, are also associated with estrogen receptor (ER) negative breast cancer in younger women. Thus, we hypothesized that there may be interactions between vitamin D and the immune system in influencing breast cancer ER status, which was tested in 490 women with incident breast cancer. There was no correlation of the levels of 25OHD with any cytokine, and their associations with tumor ER negative status were independent of each other. However, premenopausal women with low 25OHD and high TNFα levels had the highest likelihood of having ER negative cancer (odds ratio [OR] = 7.32, 95% confidence interval [CI] = 2.44−21.98), with evidence of synergy between the two (relative excess risk due to interaction [RERI] = 5.46, p for additive interaction = 0.14, and p for multiplicative interaction = 0.09). There were similar synergistic associations between 25OHD and IL5, and several IFNα2 to Th2 cytokine ratios. This is the first study to provide evidence of interactions between vitamin D and the immune system in relation to breast cancer ER status, which may inform combinational use of vitamin D and anti-inflammatory drugs for cancer prevention and therapy

  4. Combined effects of circulating levels of 25-hydroxyvitamin d and Th1 and th2 cytokines on breast cancer estrogen receptor status.

    Science.gov (United States)

    Yao, Song; Hong, Chi-Chen; McCann, Susan E; Zirpoli, Gary; Quan, Lei; Gong, Zhihong; Johnson, Candace S; Trump, Donald L; Ambrosone, Christine B

    2014-01-27

    Vitamin D has been recognized for its immune-modulating properties. We have previously found that levels of 25OHD, and cytokines including IL5, IFNα2, and TNFα, are also associated with estrogen receptor (ER) negative breast cancer in younger women. Thus, we hypothesized that there may be interactions between vitamin D and the immune system in influencing breast cancer ER status, which was tested in 490 women with incident breast cancer. There was no correlation of the levels of 25OHD with any cytokine, and their associations with tumor ER negative status were independent of each other. However, premenopausal women with low 25OHD and high TNFα levels had the highest likelihood of having ER negative cancer (odds ratio [OR] = 7.32, 95% confidence interval [CI] = 2.44-21.98), with evidence of synergy between the two (relative excess risk due to interaction [RERI] = 5.46, p for additive interaction = 0.14, and p for multiplicative interaction = 0.09). There were similar synergistic associations between 25OHD and IL5, and several IFNα2 to Th2 cytokine ratios. This is the first study to provide evidence of interactions between vitamin D and the immune system in relation to breast cancer ER status, which may inform combinational use of vitamin D and anti-inflammatory drugs for cancer prevention and therapy.

  5. Combined Effects of Circulating Levels of 25-Hydroxyvitamin D and Th1 and Th2 Cytokines on Breast Cancer Estrogen Receptor Status

    Directory of Open Access Journals (Sweden)

    Song Yao

    2014-01-01

    Full Text Available Vitamin D has been recognized for its immune-modulating properties. We have previously found that levels of 25OHD, and cytokines including IL5, IFNα2, and TNFα, are also associated with estrogen receptor (ER negative breast cancer in younger women. Thus, we hypothesized that there may be interactions between vitamin D and the immune system in influencing breast cancer ER status, which was tested in 490 women with incident breast cancer. There was no correlation of the levels of 25OHD with any cytokine, and their associations with tumor ER negative status were independent of each other. However, premenopausal women with low 25OHD and high TNFα levels had the highest likelihood of having ER negative cancer (odds ratio [OR] = 7.32, 95% confidence interval [CI] = 2.44−21.98, with evidence of synergy between the two (relative excess risk due to interaction [RERI] = 5.46, p for additive interaction = 0.14, and p for multiplicative interaction = 0.09. There were similar synergistic associations between 25OHD and IL5, and several IFNα2 to Th2 cytokine ratios. This is the first study to provide evidence of interactions between vitamin D and the immune system in relation to breast cancer ER status, which may inform combinational use of vitamin D and anti-inflammatory drugs for cancer prevention and therapy.

  6. The impact of luteal phase support on endometrial estrogen and progesterone receptor expression: a randomized control trial

    Directory of Open Access Journals (Sweden)

    Brezina Paul R

    2012-02-01

    Full Text Available Abstract Background To assess the impact of luteal phase support on the expression of estrogen receptor (ER alpha and progesterone receptors B (PR-B on the endometrium of oocyte donors undergoing controlled ovarian hyperstimulation (COH. Methods A prospective, randomized study was conducted in women undergoing controlled ovarian hyperstimulation for oocyte donation. Participants were randomized to receive no luteal support, vaginal progesterone alone, or vaginal progesterone plus orally administered 17 Beta estradiol. Endometrial biopsies were obtained at 4 time points in the luteal phase and evaluated by tissue microarray for expression of ER alpha and PR-B. Results One-hundred and eight endometrial tissue samples were obtained from 12 patients. No differences were found in expression of ER alpha and PR-B among all the specimens with the exception of one sample value. Conclusions The administration of progesterone during the luteal phase of COH for oocyte donor cycles, either with or without estrogen, does not significantly affect the endometrial expression of ER alpha and PR.

  7. Interactions Between the Cytomegalovirus Promoter and the Estrogen Response Element: Implications for Design of Estrogen-Responsive Reporter Plasmids

    OpenAIRE

    Derecka, K.; Wang, C.K.; Flint, A.P.F.

    2006-01-01

    We aimed to produce an estrogen-responsive reporter plasmid that would permit monitoring of estrogen receptor function in the uterus in vivo. The plasmid pBL-tk-CAT(+)ERE was induced by estrogen in bovine endometrial stromal cells. When the CAT gene was replaced by the secreted alkaline phosphatase SeAP, the resulting construct pBL-tk-SeAP(+)ERE remained estrogen responsive. However when the tk promoter was replaced by the cytomegalovirus (cmv) promoter, the resulting plasmid (pBL-cmv-SeAP(+)...

  8. Cytologic assessment of estrogen receptor, progesterone receptor, and HER2 status in metastatic breast carcinoma.

    Science.gov (United States)

    Pareja, Fresia; Murray, Melissa P; Jean, Ryan Des; Konno, Fumiko; Friedlander, Maria; Lin, Oscar; Edelweiss, Marcia

    2017-01-01

    Discordance in the receptor status between primary breast carcinomas (PBC) and corresponding metastasis is well documented. Interrogation of the receptor status of metastatic breast carcinoma (MBC) in cytology material is common practice; however, its utility has not been thoroughly validated. We studied patients with MBC, and evaluated the concordance rates of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between PBC surgical specimens and corresponding MBC cell blocks (CBs). We correlated the findings with clinicopathologic variables and with the fixation methods used. We searched for patients with MBC diagnosed on cytology from 2007 to 2009 and selected those with ER, PR and HER2 tested in both the PBC surgical specimens and the MBC CBs. We included CBs fixed in formalin and methanol based solution (CytoLyt®). All slides were reevaluated by cytopathologists. Clinical information was retrieved from the medical records. We studied 65 patients with PBC and MBC paired specimens. The concordance rates between PBC and MBC were 78.5%, 58.5% and 96.9%, for ER, PR and HER2, respectively. When discordant, PR status switched from positive (PBC) to negative (MBC) in most cases (23/27). The PR concordance rate was 45.2% for CBs fixed in formalin and 70.6% for those fixed with CytoLyt® (p=0.047). The ER, PR and HER2 concordance rates between the PBC and MBC CBs are similar to those reported in paired surgical specimens. PR status was the most prevalent discordance and was not accompanied by a switch in ER.

  9. Receptor-based high-throughput screening and identification of estrogens in dietary supplements using bioaffinity liquid-chromatography ion mobility mass spectrometry.

    Science.gov (United States)

    Aqai, Payam; Blesa, Natalia Gómez; Major, Hilary; Pedotti, Mattia; Varani, Luca; Ferrero, Valentina E V; Haasnoot, Willem; Nielen, Michel W F

    2013-11-01

    A high-throughput bioaffinity liquid chromatography-mass spectrometry (BioMS) approach was developed and applied for the screening and identification of recombinant human estrogen receptor α (ERα) ligands in dietary supplements. For screening, a semi-automated mass spectrometric ligand binding assay was developed applying (13)C2, (15) N-tamoxifen as non-radioactive label and fast ultra-high-performance-liquid chromatography-electrospray ionisation-triple-quadrupole-MS (UPLC-QqQ-MS), operated in the single reaction monitoring mode, as a readout system. Binding of the label to ERα-coated paramagnetic microbeads was inhibited by competing estrogens in the sample extract yielding decreased levels of the label in UPLC-QqQ-MS. The label showed high ionisation efficiency in positive electrospray ionisation (ESI) mode, so the developed BioMS approach is able to screen for estrogens in dietary supplements despite their poor ionisation efficiency in both positive and negative ESI modes. The assay was performed in a 96-well plate, and all these wells could be measured within 3 h. Estrogens in suspect extracts were identified by full-scan accurate mass and collision-cross section (CCS) values from a UPLC-ion mobility-Q-time-of-flight-MS (UPLC-IM-Q-ToF-MS) equipped with a novel atmospheric pressure ionisation source. Thanks to the novel ion source, this instrument provided picogram sensitivity for estrogens in the negative ion mode and an additional identification point (experimental CCS values) next to retention time, accurate mass and tandem mass spectrometry data. The developed combination of bioaffinity screening with UPLC-QqQ-MS and identification with UPLC-IM-Q-ToF-MS provides an extremely powerful analytical tool for early warning of ERα bioactive compounds in dietary supplements as demonstrated by analysis of selected dietary supplements in which different estrogens were identified.

  10. A molecular docking study of phytochemical estrogen mimics from dietary herbal supplements.

    Science.gov (United States)

    Powers, Chelsea N; Setzer, William N

    2015-01-01

    The purpose of this study is to use a molecular docking approach to identify potential estrogen mimics or anti-estrogens in phytochemicals found in popular dietary herbal supplements. In this study, 568 phytochemicals found in 17 of the most popular herbal supplements sold in the United States were built and docked with two isoforms of the estrogen receptor, ERα and ERβ (a total of 27 different protein crystal structures). The docking results revealed six strongly docking compounds in Echinacea, three from milk thistle (Silybum marianum), three from Gingko biloba, one from Sambucus nigra, none from maca (Lepidium meyenii), five from chaste tree (Vitex agnus-castus), two from fenugreek (Trigonella foenum-graecum), and two from Rhodiola rosea. Notably, of the most popular herbal supplements for women, there were numerous compounds that docked strongly with the estrogen receptor: Licorice (Glycyrrhiza glabra) had a total of 26 compounds strongly docking to the estrogen receptor, 15 with wild yam (Dioscorea villosa), 11 from black cohosh (Actaea racemosa), eight from muira puama (Ptychopetalum olacoides or P. uncinatum), eight from red clover (Trifolium pratense), three from damiana (Turnera aphrodisiaca or T. diffusa), and three from dong quai (Angelica sinensis). Of possible concern were the compounds from men's herbal supplements that exhibited strong docking to the estrogen receptor: Gingko biloba had three compounds, gotu kola (Centella asiatica) had two, muira puama (Ptychopetalum olacoides or P. uncinatum) had eight, and Tribulus terrestris had six compounds. This molecular docking study has revealed that almost all popular herbal supplements contain phytochemical components that may bind to the human estrogen receptor and exhibit selective estrogen receptor modulation. As such, these herbal supplements may cause unwanted side effects related to estrogenic activity.

  11. Estrogen Receptor and Progesterone Receptor Expression in Normal Terminal Duct Lobular Units Surrounding Invasive Breast Cancer

    Science.gov (United States)

    Yang, Xiaohong R.; Figueroa, Jonine D.; Hewitt, Stephen M.; Falk, Roni T.; Pfeiffer, Ruth M.; Lissowska, Jolanta; Peplonska, Beata; Brinton, Louise A.; Garcia-Closas, Montserrat; Sherman, Mark E.

    2014-01-01

    Introduction Molecular and morphological alterations related to carcinogenesis have been found in terminal duct lobular units (TDLUs), the microscopic structures from which most breast cancer precursors and cancers develop, and therefore, analysis of these structures may reveal early changes in breast carcinogenesis and etiologic heterogeneity. Accordingly, we evaluated relationships of breast cancer risk factors and tumor pathology to estrogen receptor (ER) and progesterone receptor (PR) expression in TDLUs surrounding breast cancers. Methods We analyzed 270 breast cancer cases included in a population-based breast cancer case-control study conducted in Poland. TDLUs were mapped in relation to breast cancer: within the same block as the tumor (TDLU-T), proximal to tumor (TDLU-PT), or distant from (TDLU-DT). ER/PR was quantitated using image analysis of immunohistochemically stained TDLUs prepared as tissue microarrays. Results In surgical specimens containing ER-positive breast cancers, ER and PR levels were significantly higher in breast cancer cells than in normal TDLUs, and higher in TDLU-T than in TDLU-DT or TDLU-PT, which showed similar results. Analyses combining DT-/PT TDLUs within subjects demonstrated that ER levels were significantly lower in premenopausal women vs. postmenopausal women (odds ratio [OR]=0.38, 95% confidence interval [CI]=0.19, 0.76, P=0.0064) and among recent or current menopausal hormone therapy users compared with never users (OR=0.14, 95% CI=0.046–0.43, Ptrend=0.0006). Compared with premenopausal women, TDLUs of postmenopausal women showed lower levels of PR (OR=0.90, 95% CI=0.83–0.97, Ptrend=0.007). ER and PR expression in TDLUs was associated with epidermal growth factor receptor (EGFR) expression in invasive tumors (P=0.019 for ER and P=0.03 for PR), but not with other tumor features. Conclusions Our data suggest that TDLUs near breast cancers reflect field effects, whereas those at a distance demonstrate influences of breast

  12. Itai-itai disease is not associated with polymorphisms of the estrogen receptor {alpha} gene

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, Hisahide; Hayashi, Chiyo; Lee, Myeongjin; Ayaki, Hitoshi; Sumino, Kimiaki [Kobe Univ. School of Medicine (Japan). Dept. of Public Health; Yamamoto, Ryoji; Ninomiya, Ruriko; Koizumi, Naoko [Hyogo College of Medicine (Japan). Dept. of Public Health

    1999-11-01

    Itai-itai (or ouch-ouch) disease is a syndrome accompanied by bone mineral disorders, and which may be related to oral cadmium exposure. Itai-itai predominantly affects postmenopausal women with a history of multiple childbirths. Recently, it has been reported that polymorphisms of the estrogen receptor {alpha} (ER{alpha}) gene are associated with postmenopausal reduction of bone mineral density in Japanese women. However, estrogen receptors have never been studied in itai-itai disease. In this study, we examined the genotypic distributions of PvuII and XbaI restriction fragment length polymorphisms (RFLPs) of the ER{alpha} gene in patients with itai-itai disease and compared them with those of control subjects. The RFLPs are represented here as P{sub p} (PvuII) and Xx (XbaI); the capital and small letters signify the absence and presence of restriction sites, respectively. The genotypic distributions of the patient group were: PP, 14.8%; Pp, 55.6%; pp, 29.6%; XX, 7.4%; Xx, 29.6%; and xx, 63.0%. These distributions were similar to those observed for the control groups, hence no pattern of genotypic distribution was observed that could be related to itai-itai disease. We conclude that RFLPs of the ER{alpha} gene may not be associated with itai-itai disease. (orig.)

  13. Central estrogenic pathways protect against the depressant action of acute nicotine on reflex tachycardia in female rats

    Energy Technology Data Exchange (ETDEWEB)

    El-Mas, Mahmoud M., E-mail: mahelm@hotmail.com; Fouda, Mohamed A.; El-gowilly, Sahar M.; Saad, Evan I.

    2012-02-01

    We have previously shown that acute exposure of male rats to nicotine preferentially attenuates baroreceptor-mediated control of reflex tachycardia in contrast to no effect on reflex bradycardia. Here, we investigated whether female rats are as sensitive as their male counterparts to the baroreflex depressant effect of nicotine and whether this interaction is modulated by estrogen. Baroreflex curves relating reflex chronotropic responses evoked by i.v. doses (1–16 μg/kg) of phenylephrine (PE) or sodium nitroprusside (SNP), were constructed in conscious freely moving proestrus, ovariectomized (OVX), and estrogen (50 μg/kg/day s.c., 5 days)-replaced OVX (OVXE{sub 2}) rats. Slopes of the curves were taken as a measure of baroreflex sensitivity (BRS{sub PE} and BRS{sub SNP}). Nicotine (100 μg/kg i.v.) reduced BRS{sub SNP} in OVX rats but not in proestrus or OVXE{sub 2} rats. The attenuation of reflex tachycardia by nicotine was also evident in diestrus rats, which exhibited plasma estrogen levels similar to those of OVX rats. BRS{sub PE} was not affected by nicotine in all rat preparations. Experiments were then extended to determine whether central estrogenic receptors modulate the nicotine–BRS{sub SNP} interaction. Intracisteral (i.c.) treatment of OVX rats with estrogen sulfate (0.2 μg/rat) abolished the BRS{sub SNP} attenuating effect of i.v. nicotine. This protective effect of estrogen disappeared when OVX rats were pretreated with i.c. ICI 182,780 (50 μg/rat, selective estrogen receptor antagonist). Together, these findings suggest that central neural pools of estrogen receptors underlie the protection offered by E{sub 2} against nicotine-induced baroreceptor dysfunction in female rats. -- Highlights: ► Estrogen protects against the depressant effect of nicotine on reflex tachycardia. ► The baroreflex response and estrogen status affect the nicotine–BRS interaction. ► The protection offered by estrogen is mediated via central estrogen receptors.

  14. Control of transcriptional repression of the vitellogenin receptor gene in largemouth bass (Micropterus salmoides) by select estrogen receptors isotypes.

    Science.gov (United States)

    Dominguez, Gustavo A; Bisesi, Joseph H; Kroll, Kevin J; Denslow, Nancy D; Sabo-Attwood, Tara

    2014-10-01

    The vitellogenin receptor (Vtgr) plays an important role in fish reproduction. This receptor functions to incorporate vitellogenin (Vtg), a macromolecule synthesized and released from the liver in the bloodstream, into oocytes where it is processed into yolk. Although studies have focused on the functional role of Vtgr in fish, the mechanistic control of this gene is still unexplored. Here we report the identification and analysis of the first piscine 5' regulatory region of the vtgr gene which was cloned from largemouth bass (Micropterus salmoides). Using this putative promoter sequence, we investigated a role for hormones, including insulin and 17β-estradiol (E2), in transcriptional regulation through cell-based reporter assays. No effect of insulin was observed, however, E2 was able to repress transcriptional activity of the vtgr promoter through select estrogen receptor subtypes, Esr1 and Esr2a but not Esr2b. Electrophoretic mobility shift assay demonstrated that Esr1 likely interacts with the vtgr promoter region through half ERE and/or SP1 sites, in part. Finally we also show that ethinylestradiol (EE2), but not bisphenol-A (BPA), represses promoter activity similarly to E2. These results reveal for the first time that the Esr1 isoform may play an inhibitory role in the expression of LMB vtgr mRNA under the influence of E2, and potent estrogens such as EE2. In addition, this new evidence suggests that vtgr may be a target of select endocrine disrupting compounds through environmental exposures. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Estrogen receptors in the temporomandibular joint of the baboon (Papio cynocephalus): an autoradiographic study

    Energy Technology Data Exchange (ETDEWEB)

    Aufdemorte, T.B.; Van Sickels, J.E.; Dolwick, M.F.; Sheridan, P.J.; Holt, G.R.; Aragon, S.B.; Gates, G.A.

    1986-04-01

    Using an autoradiographic method, the temporomandibular joint (TMJ) complex of five aged female baboons was studied for the presence of receptors for estradiol-17 beta. The study was performed in an effort to learn more of the pathophysiology of this joint and in an attempt to provide a scientific basis to explain the reported preponderance of women who seek and undergo treatment for signs and symptoms referable to the TMJ. This experiment revealed that the TMJ complex contains numerous cells with receptors for estrogen, particularly the articular surface of the condyle, articular disk, and capsule. Muscles of mastication contained relatively fewer receptors. As a result, one may postulate a role for the sex steroid hormones in the maintenance, repair, and/or pathogenesis of the TMJ. Additional studies are necessary to fully determine the significance of hormone receptors in this site and any correlation between diseases of the TMJ and the endocrine status of affected patients.

  16. Estrogen receptors in the temporomandibular joint of the baboon (Papio cynocephalus): an autoradiographic study

    International Nuclear Information System (INIS)

    Aufdemorte, T.B.; Van Sickels, J.E.; Dolwick, M.F.; Sheridan, P.J.; Holt, G.R.; Aragon, S.B.; Gates, G.A.

    1986-01-01

    Using an autoradiographic method, the temporomandibular joint (TMJ) complex of five aged female baboons was studied for the presence of receptors for estradiol-17 beta. The study was performed in an effort to learn more of the pathophysiology of this joint and in an attempt to provide a scientific basis to explain the reported preponderance of women who seek and undergo treatment for signs and symptoms referable to the TMJ. This experiment revealed that the TMJ complex contains numerous cells with receptors for estrogen, particularly the articular surface of the condyle, articular disk, and capsule. Muscles of mastication contained relatively fewer receptors. As a result, one may postulate a role for the sex steroid hormones in the maintenance, repair, and/or pathogenesis of the TMJ. Additional studies are necessary to fully determine the significance of hormone receptors in this site and any correlation between diseases of the TMJ and the endocrine status of affected patients

  17. Estrogenic activity of flavonoids in mice. The importance of estrogen receptor distribution, metabolism and bioavailability

    DEFF Research Database (Denmark)

    Breinholt, Vibeke; Hossaini, A.; Svendsen, Gitte W.

    2000-01-01

    The in vivo estrogenic potential of the flavonoids apigenin, kaempferol, genistein and equol was investigated in immature female mice. Genistein and equol, administered by gavage for 4 consecutive days [post-natal day (PND) 17-20, 100 mg/kg body weight], was found to significantly increase uterine...... or lower potency. Bioavailability, metabolism, the ability to alter ER alpha distribution in the uterus and the estrogenic potential of parent compound and metabolites may thus contribute to the differences in in vivo estrogenicity of dietary flavonoids....

  18. Anticancer effect of genistein on BG-1 ovarian cancer growth induced by 17 β-estradiol or bisphenol A via the suppression of the crosstalk between estrogen receptor alpha and insulin-like growth factor-1 receptor signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Kyung-A; Park, Min-Ah; Kang, Nam-Hee; Yi, Bo-Rim; Hyun, Sang-Hwan; Jeung, Eui-Bae; Choi, Kyung-Chul, E-mail: kchoi@cbu.ac.kr

    2013-11-01

    The interaction between estrogen receptor (ER) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway plays an important role in proliferation of and resistance to endocrine therapy to estrogen dependent cancers. Estrogen (E2) upregulates the expression of components of IGF-1 system and induces the downstream of mitogenic signaling cascades via phosphorylation of insulin receptor substrate-1 (IRS-1). In the present study, we evaluated the xenoestrogenic effect of bisphenol A (BPA) and antiproliferative activity of genistein (GEN) in accordance with the influence on this crosstalk. BPA was determined to affect this crosstalk by upregulating mRNA expressions of ERα and IGF-1R and inducing phosphorylation of IRS-1 and Akt in protein level in BG-1 ovarian cancer cells as E2 did. In the mouse model xenografted with BG-1 cells, BPA significantly increased a tumor burden of mice and expressions of ERα, pIRS-1, and cyclin D1 in tumor mass compared to vehicle, indicating that BPA induces ovarian cancer growth by promoting the crosstalk between ER and IGF-1R signals. On the other hand, GEN effectively reversed estrogenicity of BPA by reversing mRNA and protein expressions of ERα, IGF-1R, pIRS-1, and pAkt induced by BPA in cellular model and also significantly decreased tumor growth and in vivo expressions of ERα, pIRS-1, and pAkt in xenografted mouse model. Also, GEN was confirmed to have an antiproliferative effect by inducing apoptotic signaling cascades. Taken together, these results suggest that GEN effectively reversed the increased proliferation of BG-1 ovarian cancer by suppressing the crosstalk between ERα and IGF-1R signaling pathways upregulated by BPA or E2.

  19. Anticancer effect of genistein on BG-1 ovarian cancer growth induced by 17 β-estradiol or bisphenol A via the suppression of the crosstalk between estrogen receptor alpha and insulin-like growth factor-1 receptor signaling pathways

    International Nuclear Information System (INIS)

    Hwang, Kyung-A; Park, Min-Ah; Kang, Nam-Hee; Yi, Bo-Rim; Hyun, Sang-Hwan; Jeung, Eui-Bae; Choi, Kyung-Chul

    2013-01-01

    The interaction between estrogen receptor (ER) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway plays an important role in proliferation of and resistance to endocrine therapy to estrogen dependent cancers. Estrogen (E2) upregulates the expression of components of IGF-1 system and induces the downstream of mitogenic signaling cascades via phosphorylation of insulin receptor substrate-1 (IRS-1). In the present study, we evaluated the xenoestrogenic effect of bisphenol A (BPA) and antiproliferative activity of genistein (GEN) in accordance with the influence on this crosstalk. BPA was determined to affect this crosstalk by upregulating mRNA expressions of ERα and IGF-1R and inducing phosphorylation of IRS-1 and Akt in protein level in BG-1 ovarian cancer cells as E2 did. In the mouse model xenografted with BG-1 cells, BPA significantly increased a tumor burden of mice and expressions of ERα, pIRS-1, and cyclin D1 in tumor mass compared to vehicle, indicating that BPA induces ovarian cancer growth by promoting the crosstalk between ER and IGF-1R signals. On the other hand, GEN effectively reversed estrogenicity of BPA by reversing mRNA and protein expressions of ERα, IGF-1R, pIRS-1, and pAkt induced by BPA in cellular model and also significantly decreased tumor growth and in vivo expressions of ERα, pIRS-1, and pAkt in xenografted mouse model. Also, GEN was confirmed to have an antiproliferative effect by inducing apoptotic signaling cascades. Taken together, these results suggest that GEN effectively reversed the increased proliferation of BG-1 ovarian cancer by suppressing the crosstalk between ERα and IGF-1R signaling pathways upregulated by BPA or E2

  20. Studies on the mechanism of functional cooperativity between progesterone and estrogen receptors.

    Science.gov (United States)

    Bradshaw, M S; Tsai, S Y; Leng, X H; Dobson, A D; Conneely, O M; O'Malley, B W; Tsai, M J

    1991-09-05

    Steroid response elements (SREs) cooperate with many different cis-acting elements including NF-1 sites, CACCC boxes, and other SREs to induce target gene expression (Schule, R., Muller, M., Otsuka-Murakami, H., and Renkawitz, R. (1988) Nature 332, 87-90; Strahle, U., Schmid, W., and Schutz, G. (1988) EMBO J. 7, 3389-3395). Induction of gene expression can be additive or synergistic with respect to the level of activation by either transactivators. Two mechanisms have been proposed for how synergism occurs: 1) cooperative binding of transcriptional activators to DNA or 2) simultaneous interaction of individually bound activators with a common target protein. We have shown previously that cooperative binding of receptors is important for synergism between two progesterone response elements (PREs). Here we showed that an estrogen response element (ERE) and a PRE can also functionally cooperate and this synergism between an ERE and a PRE is not contributed by cooperative DNA binding. Furthermore, we have demonstrated that the activation domains of the progesterone receptor (PR) (C1Act) are required for synergism between two PREs and sufficient for confirming cooperative binding. However these two activation domains of PR are not sufficient for synergism between an ERE and a PRE. Additional regions within the NH2-terminal and COOH-terminal domains are also required for synergistic interaction between two heterologous SREs.

  1. Location analysis for the estrogen receptor-α reveals binding to diverse ERE sequences and widespread binding within repetitive DNA elements

    Science.gov (United States)

    Mason, Christopher E.; Shu, Feng-Jue; Wang, Cheng; Session, Ryan M.; Kallen, Roland G.; Sidell, Neil; Yu, Tianwei; Liu, Mei Hui; Cheung, Edwin; Kallen, Caleb B.

    2010-01-01

    Location analysis for estrogen receptor-α (ERα)-bound cis-regulatory elements was determined in MCF7 cells using chromatin immunoprecipitation (ChIP)-on-chip. Here, we present the estrogen response element (ERE) sequences that were identified at ERα-bound loci and quantify the incidence of ERE sequences under two stringencies of detection: ERE sequence. We demonstrate that ∼50% of all ERα-bound loci do not have a discernable ERE and show that most ERα-bound EREs are not perfect consensus EREs. Approximately one-third of all ERα-bound ERE sequences reside within repetitive DNA sequences, most commonly of the AluS family. In addition, the 3-bp spacer between the inverted ERE half-sites, rather than being random nucleotides, is C(A/T)G-enriched at bona fide receptor targets. Diverse ERα-bound loci were validated using electrophoretic mobility shift assay and ChIP-polymerase chain reaction (PCR). The functional significance of receptor-bound loci was demonstrated using luciferase reporter assays which proved that repetitive element ERE sequences contribute to enhancer function. ChIP-PCR demonstrated estrogen-dependent recruitment of the coactivator SRC3 to these loci in vivo. Our data demonstrate that ERα binds to widely variant EREs with less sequence specificity than had previously been suspected and that binding at repetitive and nonrepetitive genomic targets is favored by specific trinucleotide spacers. PMID:20047966

  2. Location analysis for the estrogen receptor-alpha reveals binding to diverse ERE sequences and widespread binding within repetitive DNA elements.

    Science.gov (United States)

    Mason, Christopher E; Shu, Feng-Jue; Wang, Cheng; Session, Ryan M; Kallen, Roland G; Sidell, Neil; Yu, Tianwei; Liu, Mei Hui; Cheung, Edwin; Kallen, Caleb B

    2010-04-01

    Location analysis for estrogen receptor-alpha (ERalpha)-bound cis-regulatory elements was determined in MCF7 cells using chromatin immunoprecipitation (ChIP)-on-chip. Here, we present the estrogen response element (ERE) sequences that were identified at ERalpha-bound loci and quantify the incidence of ERE sequences under two stringencies of detection: ERE sequence. We demonstrate that approximately 50% of all ERalpha-bound loci do not have a discernable ERE and show that most ERalpha-bound EREs are not perfect consensus EREs. Approximately one-third of all ERalpha-bound ERE sequences reside within repetitive DNA sequences, most commonly of the AluS family. In addition, the 3-bp spacer between the inverted ERE half-sites, rather than being random nucleotides, is C(A/T)G-enriched at bona fide receptor targets. Diverse ERalpha-bound loci were validated using electrophoretic mobility shift assay and ChIP-polymerase chain reaction (PCR). The functional significance of receptor-bound loci was demonstrated using luciferase reporter assays which proved that repetitive element ERE sequences contribute to enhancer function. ChIP-PCR demonstrated estrogen-dependent recruitment of the coactivator SRC3 to these loci in vivo. Our data demonstrate that ERalpha binds to widely variant EREs with less sequence specificity than had previously been suspected and that binding at repetitive and nonrepetitive genomic targets is favored by specific trinucleotide spacers.

  3. Establishment of a normal-derived estrogen receptor-positive cell line comparable to the prevailing human breast cancer subtype

    DEFF Research Database (Denmark)

    Hopkinson, Branden Michael; Klitgaard, Marie Christine; Petersen, Ole William

    2017-01-01

    Understanding human cancer increasingly relies on insight gained from subtype specific comparisons between malignant and non-malignant cells. The most frequent subtype in breast cancer is the luminal. By far the most frequently used model for luminal breast cancer is the iconic estrogen receptor-...

  4. Risk of estrogen receptor-positive and -negative breast cancer and single-nucleotide polymorphism 2q35-rs13387042

    DEFF Research Database (Denmark)

    Milne, Roger L; Benítez, Javier; Nevanlinna, Heli

    2009-01-01

    BACKGROUND: A recent genome-wide association study identified single-nucleotide polymorphism (SNP) 2q35-rs13387042 as a marker of susceptibility to estrogen receptor (ER)-positive breast cancer. We attempted to confirm this association using the Breast Cancer Association Consortium. METHODS: 2q35...

  5. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on estrogenic responses

    Energy Technology Data Exchange (ETDEWEB)

    Romkes, M.

    1988-01-01

    The competitive receptor binding affinities of thirteen 2-substituted-3,7,8-trichlorodibenzo-p-dioxins to hepatic cytosol from rat, mouse, guinea pig and hamster were determined using ({sup 3}H)-2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) as the radio-ligand. Significant species-dependent structural differences in the Ah receptor ligand binding site were observed and support the heterologous nature of the receptor protein. The interactions of 2,3,7,8-TCDD and estrogenic responses in the female rat and human breast cancer cells were also investigated. Cotreatment of 25-day-old female Long Evans rats with 20 or 80 ug/kg of 2,3,7,8-TCDD resulted in a dose-dependent decrease in both uterine and hepatic estrogen receptor (ER) levels. Moreover, these levels are decreased for at least ten days and appear to be related to the tissue persistence of 2,3,7,8-TCDD. In contrast, estradiol elevated uterine and hepatic ER levels and increased uterine wet weights. Cotreatment of the rats with 2,3,7,8-TCDD and estradiol resulted in hepatic and uterine ER levels which were comparable to those observed in the control rats; in addition, 2,3,7,8-TCDD also antagonized the effects of estradiol-induced uterine wet weights.

  6. Dose-related estrogen effects on gene expression in fetal mouse prostate mesenchymal cells.

    Directory of Open Access Journals (Sweden)

    Julia A Taylor

    Full Text Available Developmental exposure of mouse fetuses to estrogens results in dose-dependent permanent effects on prostate morphology and function. Fetal prostatic mesenchyme cells express estrogen receptor alpha (ERα and androgen receptors and convert stimuli from circulating estrogens and androgens into paracrine signaling to regulate epithelial cell proliferation and differentiation. To obtain mechanistic insight into the role of different doses of estradiol (E2 in regulating mesenchymal cells, we examined E2-induced transcriptomal changes in primary cultures of fetal mouse prostate mesenchymal cells. Urogenital sinus mesenchyme cells were obtained from male mouse fetuses at gestation day 17 and exposed to 10 pM, 100 pM or 100 nM E2 in the presence of a physiological concentration of dihydrotestosterone (0.69 nM for four days. Gene ontology studies suggested that low doses of E2 (10 pM and 100 pM induce genes involved in morphological tissue development and sterol biosynthesis but suppress genes involved in growth factor signaling. Genes involved in cell adhesion were enriched among both up-regulated and down-regulated genes. Genes showing inverted-U-shape dose responses (enhanced by E2 at 10 pM E2 but suppressed at 100 pM were enriched in the glycolytic pathway. At the highest dose (100 nM, E2 induced genes enriched for cell adhesion, steroid hormone signaling and metabolism, cytokines and their receptors, cell-to-cell communication, Wnt signaling, and TGF- β signaling. These results suggest that prostate mesenchymal cells may regulate epithelial cells through direct cell contacts when estrogen level is low whereas secreted growth factors and cytokines might play significant roles when estrogen level is high.

  7. Select estrogens within the complex formulation of conjugated equine estrogens (Premarin® are protective against neurodegenerative insults: implications for a composition of estrogen therapy to promote neuronal function and prevent Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Brinton Roberta

    2006-03-01

    Full Text Available Abstract Background Results of the Women's Health Initiative Memory Study (WHIMS raised concerns regarding the timing and formulation of hormone interventions. Conjugated equine estrogens (CEE, used as the estrogen therapy in the WHIMS trial, is a complex formulation containing multiple estrogens, including several not secreted by human ovaries, as well as other biologically active steroids. Although the full spectrum of estrogenic components present in CEE has not yet been resolved, 10 estrogens have been identified. In the present study, we sought to determine which estrogenic components, at concentrations commensurate with their plasma levels achieved following a single oral dose of 0.625 mg CEE (the dose used in the WHIMS trial in women, are neuroprotective and whether combinations of those neuroprotective estrogens provide added benefit. Further, we sought, through computer-aided modeling analyses, to investigate the potential correlation of the molecular mechanisms that conferred estrogen neuroprotection with estrogen interactions with the estrogen receptor (ER. Results Cultured basal forebrain neurons were exposed to either β-amyloid25–35 or excitotoxic glutamate with or without pretreatment with estrogens followed by neuroprotection analyses. Three indicators of neuroprotection that rely on different aspects of neuronal damage and viability, LDH release, intracellular ATP level and MTT formazan formation, were used to assess neuroprotective efficacy. Results of these analyses indicate that the estrogens, 17α-estradiol, 17β-estradiol, equilin, 17α-dihydroequilin, equilinen, 17α-dihydroequilenin, 17β-dihydroequilenin, and Δ8,9-dehydroestrone were each significantly neuroprotective in reducing neuronal plasma membrane damage induced by glutamate excitotoxicity. Of these estrogens, 17β-estradiol and Δ8,9-dehydroestrone were effective in protecting neurons against β-amyloid25–35-induced intracellular ATP decline

  8. Editor's Highlight: Transcriptome Profiling Reveals Bisphenol A Alternatives Activate Estrogen Receptor Alpha in Human Breast Cancer Cells.

    Science.gov (United States)

    Mesnage, Robin; Phedonos, Alexia; Arno, Matthew; Balu, Sucharitha; Corton, J Christopher; Antoniou, Michael N

    2017-08-01

    Plasticizers with estrogenic activity, such as bisphenol A (BPA), have potential adverse health effects in humans. Due to mounting evidence of these health effects, BPA is being phased out and replaced by other bisphenol variants in "BPA-free" products. We have compared estrogenic activity of BPA with 6 bisphenol analogues [bisphenol S (BPS); bisphenol F (BPF); bisphenol AP (BPAP); bisphenol AF (BPAF); bisphenol Z (BPZ); bisphenol B (BPB)] in 3 human breast cancer cell lines. Estrogenicity was assessed (10-11-10-4 M) by cell growth in an estrogen receptor (ER)-mediated cell proliferation assay, and by the induction of estrogen response element-mediated transcription in a luciferase assay. BPAF was the most potent bisphenol, followed by BPB > BPZ ∼ BPA > BPF ∼ BPAP > BPS. The addition of ICI 182,780 antagonized the activation of ERs. Data mining of ToxCast high-throughput screening assays confirm our results but also show divergence in the sensitivities of the assays. Gene expression profiles were determined in MCF-7 cells by microarray analysis. The comparison of transcriptome profile alterations resulting from BPA alternatives with an ERα gene expression biomarker further indicates that all BPA alternatives act as ERα agonists in MCF-7 cells. These results were confirmed by Illumina-based RNA sequencing. In conclusion, BPA alternatives are not necessarily less estrogenic than BPA in human breast cancer cells. BPAF, BPB, and BPZ were more estrogenic than BPA. These findings point to the importance of better understanding the risk of adverse effects from exposure to BPA alternatives, including hormone-dependent breast cancer. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology.

  9. DCE-MRI texture analysis with tumor subregion partitioning for predicting Ki-67 status of estrogen receptor-positive breast cancers

    KAUST Repository

    Fan, Ming; Cheng, Hu; Zhang, Peng; Gao, Xin; Zhang, Juan; Shao, Guoliang; Li, Lihua

    2017-01-01

    Breast tumor heterogeneity is related to risk factors that lead to worse prognosis, yet such heterogeneity has not been well studied.To predict the Ki-67 status of estrogen receptor (ER)-positive breast cancer patients via analysis of tumor

  10. A common variant at the TERT-CLPTM1L locus is associated with estrogen receptor-negative breast cancer.

    Science.gov (United States)

    Haiman, Christopher A; Chen, Gary K; Vachon, Celine M; Canzian, Federico; Dunning, Alison; Millikan, Robert C; Wang, Xianshu; Ademuyiwa, Foluso; Ahmed, Shahana; Ambrosone, Christine B; Baglietto, Laura; Balleine, Rosemary; Bandera, Elisa V; Beckmann, Matthias W; Berg, Christine D; Bernstein, Leslie; Blomqvist, Carl; Blot, William J; Brauch, Hiltrud; Buring, Julie E; Carey, Lisa A; Carpenter, Jane E; Chang-Claude, Jenny; Chanock, Stephen J; Chasman, Daniel I; Clarke, Christine L; Cox, Angela; Cross, Simon S; Deming, Sandra L; Diasio, Robert B; Dimopoulos, Athanasios M; Driver, W Ryan; Dünnebier, Thomas; Durcan, Lorraine; Eccles, Diana; Edlund, Christopher K; Ekici, Arif B; Fasching, Peter A; Feigelson, Heather S; Flesch-Janys, Dieter; Fostira, Florentia; Försti, Asta; Fountzilas, George; Gerty, Susan M; Giles, Graham G; Godwin, Andrew K; Goodfellow, Paul; Graham, Nikki; Greco, Dario; Hamann, Ute; Hankinson, Susan E; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Holbrook, Andrea; Hoover, Robert N; Hu, Jennifer J; Hunter, David J; Ingles, Sue A; Irwanto, Astrid; Ivanovich, Jennifer; John, Esther M; Johnson, Nicola; Jukkola-Vuorinen, Arja; Kaaks, Rudolf; Ko, Yon-Dschun; Kolonel, Laurence N; Konstantopoulou, Irene; Kosma, Veli-Matti; Kulkarni, Swati; Lambrechts, Diether; Lee, Adam M; Marchand, Loïc Le; Lesnick, Timothy; Liu, Jianjun; Lindstrom, Sara; Mannermaa, Arto; Margolin, Sara; Martin, Nicholas G; Miron, Penelope; Montgomery, Grant W; Nevanlinna, Heli; Nickels, Stephan; Nyante, Sarah; Olswold, Curtis; Palmer, Julie; Pathak, Harsh; Pectasides, Dimitrios; Perou, Charles M; Peto, Julian; Pharoah, Paul D P; Pooler, Loreall C; Press, Michael F; Pylkäs, Katri; Rebbeck, Timothy R; Rodriguez-Gil, Jorge L; Rosenberg, Lynn; Ross, Eric; Rüdiger, Thomas; Silva, Isabel dos Santos; Sawyer, Elinor; Schmidt, Marjanka K; Schulz-Wendtland, Rüdiger; Schumacher, Fredrick; Severi, Gianluca; Sheng, Xin; Signorello, Lisa B; Sinn, Hans-Peter; Stevens, Kristen N; Southey, Melissa C; Tapper, William J; Tomlinson, Ian; Hogervorst, Frans B L; Wauters, Els; Weaver, JoEllen; Wildiers, Hans; Winqvist, Robert; Van Den Berg, David; Wan, Peggy; Xia, Lucy Y; Yannoukakos, Drakoulis; Zheng, Wei; Ziegler, Regina G; Siddiq, Afshan; Slager, Susan L; Stram, Daniel O; Easton, Douglas; Kraft, Peter; Henderson, Brian E; Couch, Fergus J

    2011-10-30

    Estrogen receptor (ER)-negative breast cancer shows a higher incidence in women of African ancestry compared to women of European ancestry. In search of common risk alleles for ER-negative breast cancer, we combined genome-wide association study (GWAS) data from women of African ancestry (1,004 ER-negative cases and 2,745 controls) and European ancestry (1,718 ER-negative cases and 3,670 controls), with replication testing conducted in an additional 2,292 ER-negative cases and 16,901 controls of European ancestry. We identified a common risk variant for ER-negative breast cancer at the TERT-CLPTM1L locus on chromosome 5p15 (rs10069690: per-allele odds ratio (OR) = 1.18 per allele, P = 1.0 × 10(-10)). The variant was also significantly associated with triple-negative (ER-negative, progesterone receptor (PR)-negative and human epidermal growth factor-2 (HER2)-negative) breast cancer (OR = 1.25, P = 1.1 × 10(-9)), particularly in younger women (<50 years of age) (OR = 1.48, P = 1.9 × 10(-9)). Our results identify a genetic locus associated with estrogen receptor negative breast cancer subtypes in multiple populations.

  11. Importance of the Sequence-Directed DNA Shape for Specific Binding Site Recognition by the Estrogen-Related Receptor

    Directory of Open Access Journals (Sweden)

    Kareem Mohideen-Abdul

    2017-06-01

    Full Text Available Most nuclear receptors (NRs bind DNA as dimers, either as hetero- or as homodimers on DNA sequences organized as two half-sites with specific orientation and spacing. The dimerization of NRs on their cognate response elements (REs involves specific protein–DNA and protein–protein interactions. The estrogen-related receptor (ERR belongs to the steroid hormone nuclear receptor (SHR family and shares strong similarity in its DNA-binding domain (DBD with that of the estrogen receptor (ER. In vitro, ERR binds with high affinity inverted repeat REs with a 3-bps spacing (IR3, but in vivo, it preferentially binds to single half-site REs extended at the 5′-end by 3 bp [estrogen-related response element (ERREs], thus explaining why ERR was often inferred as a purely monomeric receptor. Since its C-terminal ligand-binding domain is known to homodimerize with a strong dimer interface, we investigated the binding behavior of the isolated DBDs to different REs using electrophoretic migration, multi-angle static laser light scattering (MALLS, non-denaturing mass spectrometry, and nuclear magnetic resonance. In contrast to ER DBD, ERR DBD binds as a monomer to EREs (IR3, such as the tff1 ERE-IR3, but we identified a DNA sequence composed of an extended half-site embedded within an IR3 element (embedded ERRE/IR3, where stable dimer binding is observed. Using a series of chimera and mutant DNA sequences of ERREs and IR3 REs, we have found the key determinants for the binding of ERR DBD as a dimer. Our results suggest that the sequence-directed DNA shape is more important than the exact nucleotide sequence for the binding of ERR DBD to DNA as a dimer. Our work underlines the importance of the shape-driven DNA readout mechanisms based on minor groove recognition and electrostatic potential. These conclusions may apply not only to ERR but also to other members of the SHR family, such as androgen or glucocorticoid, for which a strong well-conserved half

  12. Estrogen receptor-a in medial amygdala neurons regulates body weight

    Science.gov (United States)

    Estrogen receptor–a (ERa) activity in the brain prevents obesity in both males and females. However, the ERa-expressing neural populations that regulate body weight remain to be fully elucidated. Here we showed that single-minded–1 (SIM1) neurons in the medial amygdala (MeA) express abundant levels ...

  13. The human oxytocin gene promoter is regulated by estrogens.

    Science.gov (United States)

    Richard, S; Zingg, H H

    1990-04-15

    Gonadal steroids affect brain function primarily by altering the expression of specific genes, yet the specific mechanisms by which neuronal target genes undergo such regulation are unknown. Recent evidence suggests that the expression of the neuropeptide gene for oxytocin (OT) is modulated by estrogens. We therefore examined the possibility that this regulation occurred via a direct interaction of the estrogen-receptor complex with cis-acting elements flanking the OT gene. DNA-mediated gene transfer experiments were performed using Neuro-2a neuroblastoma cells and chimeric plasmids containing portions of the human OT gene 5'-glanking region linked to the chloramphenicol acetyltransferase gene. We identified a 19-base pair region located at -164 to -146 upstream of the transcription start site which is capable of conferring estrogen responsiveness to the homologous as well as to a heterologous promoter. The hormonal response is strictly dependent on the presence of intracellular estrogen receptors, since estrogen induced stimulation occurred only in Neuro-2a cells co-transfected with an expression vector for the human estrogen receptor. The identified region contains a novel imperfect palindrome (GGTGACCTTGACC) with sequence similarity to other estrogen response elements (EREs). To define cis-acting elements that function in synergism with the ERE, sequences 3' to the ERE were deleted, including the CCAAT box, two additional motifs corresponding to the right half of the ERE palindrome (TGACC), as well as a CTGCTAA heptamer similar to the "elegans box" found in Caenorhabditis elegans. Interestingly, optimal function of the identified ERE was fully independent of these elements and only required a short promoter region (-49 to +36). Our studies define a molecular mechanism by which estrogens can directly modulate OT gene expression. However, only a subset of OT neurons are capable of binding estrogens, therefore, direct action of estrogens on the OT gene may be

  14. High-affinity binding of [3H]estradiol-17 beta by an estrogen receptor in the liver of the turtle

    International Nuclear Information System (INIS)

    Ho, S.M.; Fehrer, S.; Yu, M.; Liang, L.C.; Press, D.

    1988-01-01

    Specific [3H]estradiol-17 beta ([3H]E2) binding activity (EBA) with characteristics of an estrogen receptor (ER) was demonstrated in cytosols and nuclear extracts of the female turtle, Chrysemys picta. Three different receptor assays (dextran-coated charcoal assay, hydroxylapatite batch procedure, and DNA-cellulose chromatography) were evaluated in terms of their applicability in analyzing large numbers of samples. For the measurement of cytosolic EBA, the hydroxylapatite batch procedure was found to be the most reliable assay. On the other hand, the dextran-coated charcoal assay was found to be the most appropriate method for the measurement of nuclear EBA. Turtle hepatic EBA binds [3H]E2 with high affinity (cytosolic, 17.4 +/- 2.8 X 10(9) M-1; nuclear, 17.7 +/- 1.9 X 10(9) M-1), limited capacity (cytosolic, 133.7 +/- 4.6 fmol/g tissue; nuclear, 81.1 +/- 9.0 fmol/g tissue), and strict steroid specificity. The EBA bound natural estrogens (E2, estrone, estriol) as well as the nonsteroidal estrogen, diethylstilbestrol, but exhibited little affinity for androgens, progesterone, or corticosterone. The turtle hepatic EBA resembled mammalian and avian ERs in terms of binding characteristics; however, unlike mammalian and avian ERs it was shown to be heat-labile. Incubation at 30 degrees caused rapid loss of [3H]E2 binding activity in both cytosolic and nuclear fractions. The exchange between [3H]E2 and the endogenously bound estrogen was slow at 4 and 15 degrees, but the exchange process was facilitated in the presence of the chaotropic salt, NaSCN. Establishment of quantitation methods for both cytosolic and nuclear forms of EBA will enable future investigation of the mechanism and regulation of estrogen action in the liver of this turtle species

  15. The role of P450 metabolism in the estrogenic activity of bifenthrin in fish.

    Science.gov (United States)

    DeGroot, Breanna C; Brander, Susanne M

    2014-11-01

    Bifenthrin, a pyrethroid pesticide, is estrogenic in vivo in fishes. However, bifenthrin is documented to be anti-estrogenic in vitro, in the ER-CALUX (estrogen receptor) cell line. We investigated whether metabolite formation is the reason for this incongruity. We exposed Menidia beryllina (inland silversides) to 10ng/l bifenthrin, 10ng/l 4-hydroxy bifenthrin, and 10ng/l bifenthrin with 25μg/l piperonyl butoxide (PBO) - a P450 inhibitor. Metabolite-exposed juveniles had significantly higher estrogen-mediated protein levels (choriogenin) than bifenthrin/PBO-exposed, while bifenthrin alone was intermediate (not significantly different from either). This suggests that metabolites are the main contributors to bifenthrin's in vivo estrogenicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Estrogen-related receptor gamma and hearing function: evidence of a role in humans and mice.

    Science.gov (United States)

    Nolan, Lisa S; Maier, Hannes; Hermans-Borgmeyer, Irm; Girotto, Giorgia; Ecob, Russell; Pirastu, Nicola; Cadge, Barbara A; Hübner, Christian; Gasparini, Paolo; Strachan, David P; Davis, Adrian; Dawson, Sally J

    2013-08-01

    Since estrogen is thought to protect pre-menopausal women from age-related hearing loss, we investigated whether variation in estrogen-signalling genes is linked to hearing status in the 1958 British Birth Cohort. This analysis implicated the estrogen-related receptor gamma (ESRRG) gene in determining adult hearing function and was investigated further in a total of 6134 individuals in 3 independent cohorts: (i) the 1958 British Birth Cohort; (ii) a London ARHL case-control cohort; and (iii) a cohort from isolated populations of Italy and Silk Road countries. Evidence of an association between the minor allele of single nucleotide polymorphism (SNP) rs2818964 and hearing status was found in females, but not in males in 2 of these cohorts: p = 0.0058 (London ARHL) and p = 0.0065 (Carlantino, Italy). Furthermore, assessment of hearing in Esrrg knock-out mice revealed a mild 25-dB hearing loss at 5 weeks of age. At 12 weeks, average hearing thresholds in female mice((-/-)) were 15 dB worse than in males((-/-)). Together these data indicate ESRRG plays a role in maintenance of hearing in both humans and mice. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Receptor-targeted metalloradiopharmaceuticals. Final technical report

    International Nuclear Information System (INIS)

    Green, Mark A.

    2000-01-01

    Copper (II) and platinum (II) coordination complexes were prepared and characterized. These complexes were designed to afford structural homology with steroidal and non-steroidal estrogens for possible use as receptor-targeted radiopharmaceuticals. While weak affinity for the estrogen receptor was detectable, none would appear to have sufficient receptor-affinity for estrogen-receptor-targeted imaging or therapy

  18. Characterization of estrogen receptor-negative/progesterone receptor-positive breast cancer.

    Science.gov (United States)

    Shen, Tiansheng; Brandwein-Gensler, Margaret; Hameed, Omar; Siegal, Gene P; Wei, Shi

    2015-11-01

    Despite the controversies, estrogen receptor-negative/progesterone receptor-positive (ER-/PR+) breast cancers have a reported incidence of 1% to 4%. These tumors are less well defined, and it is unclear whether ER-/PR+ represents a distinct subtype. Thus, we analyzed 5374 consecutive breast cancers to characterize the clinicopathological features of this underrecognized subset of tumors. The ER-/PR+ tumors, constituting 2.3% of the total, were mostly high grade and significantly seen in younger patients and African American women when compared with the ER+/PR+ and ER+/PR- groups, but similar to that of ER-/PR- phenotype (P < .0001). A significantly prolonged relapse-free survival (RFS) was associated with the ER+/PR+ subtype when compared with the ER+/PR- (P = .0002) or ER-/PR+ (P = .0004) tumors, whereas all 3 groups showed a superior outcome to that of the ER-/PR- phenotype. In the subset of patients receiving endocrine therapy, those with ER+/PR+ tumors had a significantly prolonged RFS (P = .001) and disease-specific survival (P = .005) when compared with the group with an ER+/PR- phenotype, but did not significantly differ from those with ER-/PR+ tumors. No significant survival advantage was found between the ER+/PR- and ER-/PR+ tumors in any group of patients analyzed. Furthermore, a higher PR expression was associated with a favorable RFS and disease-specific survival in the patients with ER-/PR+ tumors. Therefore, the ER-/PR+ tumors demonstrate a similar, if not higher than, response rate to endocrine therapy when compared with the ER+/PR- tumors and thus are important to identify. Routine PR testing remains necessary in assisting clinical decision making in the pursuit of precision medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Estrogen Receptor β in Melanoma: From Molecular Insights to Potential Clinical Utility

    Directory of Open Access Journals (Sweden)

    Monica Marzagalli

    2016-10-01

    Full Text Available Cutaneous melanoma is an aggressive tumor with its incidence increasing faster than any other cancer in the past decades. Melanoma is a heterogeneous tumor, with most patients harboring mutations in the BRAF or NRAS oncogenes, leading to the overactivation of the MAPK/ERK and PI3K/Akt pathways. The current therapeutic approaches are based on therapies targeting mutated BRAF and the downstream pathway, and on monoclonal antibodies against the immune checkpoint blockade. However, treatment resistance and side effects are common events of these therapeutic strategies.Increasing evidence supports that melanoma is a hormone-related cancer. Melanoma incidence is higher in males than in females and females have a significant survival advantage over men. Estrogens exert their effects through estrogen receptors (ER and ERβ that exert opposite effects on cancer growth: ER is associated with a proliferative action and ERβ with an anticancer effect. ERβ is the predominant estrogen receptor in melanoma and its expression decreases in melanoma progression, supporting its role as a tumor suppressor. Thus, ERβ is now considered as an effective molecular target for melanoma treatment. 17β-estradiol was reported to inhibit melanoma cells proliferation. However, clinical trials did not provide the expected survival benefits. In vitro studies demonstrate that ERβ ligands inhibit the proliferation of melanoma cells harboring the NRAS (but not the BRAF mutation, suggesting that ERβ activation might impair melanoma development through the inhibition of the PI3K/Akt pathway. These data suggest that ERβ agonists might be considered as an effective treatment strategy, in combination with MAPK inhibitors, for NRAS mutant melanomas. In an era of personalized medicine, pretreatment evaluation of the expression of ER isoforms together with the concurrent oncogenic mutations should be considered before selecting the most appropriate therapeutic intervention

  20. Dopamine activates masculine sexual behavior independent of the estrogen receptor alpha.

    Science.gov (United States)

    Wersinger, S R; Rissman, E F

    2000-06-01

    Estrogen receptor alpha (ERalpha) is believed to be a critical part of the regulatory processes involved in normal reproduction and sexual behavior. However, in this study we show the ERalpha is not required for display of masculine sexual behavior. Male and female, ERalpha knock-out (ERalphaKO) and wild-type mice were gonadectomized and implanted with testosterone. Sexual behavior and social preferences were tested after injection of the dopamine agonist, apomorphine (APO), or vehicle. All wild-type mice showed normal masculine behavior, including mounts and pelvic thrusts in females, and ejaculation in males. In agreement with past reports, ERalphaKO mice, given vehicle, failed to show mating behavior. Yet, ERalphaKO males given APO showed masculine copulatory behavior and chemoinvestigatory behavior directed at females. ERalphaKO females, treated with APO, mounted and thrusted when tested with receptive females. HPLC revealed that wild-type and ERalphaKO mice had equivalent catecholamine content in brain regions associated with masculine sexual behavior. These data show that the ERalpha is not essential during development or adulthood for the expression of masculine sexual behavior in mice. Moreover, dopamine can activate sexual behavior via a mechanism that either acts on an ER other than ERalpha or via an estrogen-independent pathway.

  1. 20180312 - Retrofitting an Estrogen Receptor Transactivation Assay with Metabolic Competence Using Alginate Immobilization of Metabolic Enzymes (AIME) (SOT)

    Science.gov (United States)

    The VM7Luc4E2 estrogen receptor (ER) transactivation assay is an OECD approved method (TG 457) for the detection of ER agonists and antagonists, and is also part of the Tox21 high-throughput screening (HTS) portfolio. Despite its international acceptance as a screening assay, imm...

  2. 17β-estradiol induces stearoyl-CoA desaturase-1 expression in estrogen receptor-positive breast cancer cells

    International Nuclear Information System (INIS)

    Belkaid, Anissa; Duguay, Sabrina R.; Ouellette, Rodney J.; Surette, Marc E.

    2015-01-01

    To sustain cell growth, cancer cells exhibit an altered metabolism characterized by increased lipogenesis. Stearoyl-CoA desaturase-1 (SCD-1) catalyzes the production of monounsaturated fatty acids that are essential for membrane biogenesis, and is required for cell proliferation in many cancer cell types. Although estrogen is required for the proliferation of many estrogen-sensitive breast carcinoma cells, it is also a repressor of SCD-1 expression in liver and adipose. The current study addresses this apparent paradox by investigating the impact of estrogen on SCD-1 expression in estrogen receptor-α-positive breast carcinoma cell lines. MCF-7 and T47D mammary carcinomas cells and immortalized MCF-10A mammary epithelial cells were hormone-starved then treated or not with 17β-estradiol. SCD-1 activity was assessed by measuring cellular monounsaturated/saturated fatty acid (MUFA/SFA) ratios, and SCD-1 expression was measured by qPCR, immunoblot, and immunofluorescence analyses. The role of SCD-1 in cell proliferation was measured following treatment with the SCD-1 inhibitor A959372 and following SCD-1 silencing using siRNA. The involvement of IGF-1R on SCD-1 expression was measured using the IGF-1R antagonist AG1024. The expression of SREBP-1c, a transcription factor that regulates SCD-1, was measured by qPCR, and by immunoblot analyses. 17β-estradiol significantly induced cell proliferation and SCD-1 activity in MCF-7 and T47D cells but not MCF-10A cells. Accordingly, 17β-estradiol significantly increased SCD-1 mRNA and protein expression in MCF-7 and T47D cells compared to untreated cells. Treatment of MCF-7 cells with 4-OH tamoxifen or siRNA silencing of estrogen receptor-α largely prevented 17β-estradiol-induced SCD-1 expression. 17β-estradiol increased SREBP-1c expression and induced the mature active 60 kDa form of SREBP-1. The selective SCD-1 inhibitor or siRNA silencing of SCD-1 blocked the 17β-estradiol-induced cell proliferation and increase in

  3. Estrogen receptor alpha localization in the testes of men with normal spermatogenesis.

    Science.gov (United States)

    Filipiak, Eliza; Suliborska, Dagmara; Laszczynska, Maria; Walczak-Jedrzejowska, Renata; Oszukowska, Elzbieta; Marchlewska, Katarzyna; Kula, Krzysztof; Slowikowska-Hilczer, Jolanta

    2013-10-08

    It is known that estrogens act on the male reproductive tract by binding to estrogen receptors (ER) α and β. However, studies on ER localization in the human testis are discordant. The aim of this study was to investigate the localization of ERα in the testes of adult men with normal spermatogenesis. Semen analysis of ten adult men revealed azoospermia. FSH, LH and testosterone serum concentrations were within normal values, and the volume of the testes was normal, hence obstructive azoospermia was suspected. The tissues from testicular surgical biopsies were fixed in Bouin's fluid and embedded in paraffin. Assessments of the seminiferous epithelium (scoring 10 to -1), the number of Leydig cells (scoring 1 to 5), the areal fraction of intertubular space (IS), measurements of seminiferous tubule diameter, and the thickness of the tubular wall, were performed on microscopic sections. Immunohistochemical staining was applied with monoclonal antibodies against ERα. The mean spermatogenesis score was 10 points; IS - 30.6 ± 8.1%; seminiferous tubule diameter - 193.9 ± 19.4 μm; thickness of tubular wall - 7.44 ± 1.1 μm; number of Leydig cells - 1.6 ± 1.1 points. Immunohistochemical staining showed the localization of ERα to be in the Sertoli and Leydig cell cytoplasm, while ERα was absent in germ cells. The results of testicular tissue analysis confirmed its normal structure and normal, full spermatogenesis. The presence of ERα in Sertoli and Leydig cells in normal human testis demonstrated in this study suggests that estrogens may affect testicular function.

  4. Genetic Variants of GPER/GPR30, a Novel Estrogen-Related G Protein Receptor, Are Associated with Human Seminoma

    Directory of Open Access Journals (Sweden)

    Nicolas Chevalier

    2014-01-01

    Full Text Available Testicular germ cell tumors (TGCTs are the most common solid cancers in young men, with an increasing incidence over several years. However, their pathogenesis remains a matter of debate. Some epidemiological data suggest the involvement of both environmental and genetic factors. We reported two distinct effects of estrogens and/or xeno-estrogens on in vitro human seminoma-derived cells proliferation: (1 an antiproliferative effect via a classical estrogen receptor beta-dependent pathway, and (2 a promotive effect via a non-classical membrane G-protein-coupled receptor, GPR30/GPER, which is only overexpressed in seminomas, the most common TGCT. In order to explain this overexpression, we investigated the possible association of polymorphisms in the GPER gene by using allele-specific tetra-primer polymerase chain reaction performed on tissue samples from 150 paraffin-embedded TGCT specimens (131 seminomas, 19 non seminomas. Compared to control population, loss of homozygous ancestral genotype GG in two polymorphisms located in the promoter region of GPER (rs3808350 and rs3808351 was more frequent in seminomas but not in non-seminomas (respectively, OR = 1.960 (1.172–3.277 and 7.000 (2.747–17.840; p < 0.01. These polymorphisms may explain GPER overexpression and represent a genetic factor of susceptibility supporting the contribution of environmental GPER ligands in testicular carcinogenesis.

  5. Identification of estrogen receptor dimer selective ligands reveals growth-inhibitory effects on cells that co-express ERα and ERβ.

    Directory of Open Access Journals (Sweden)

    Emily Powell

    Full Text Available Estrogens play essential roles in the progression of mammary and prostatic diseases. The transcriptional effects of estrogens are transduced by two estrogen receptors, ERα and ERβ, which elicit opposing roles in regulating proliferation: ERα is proliferative while ERβ is anti-proliferative. Exogenous expression of ERβ in ERα-positive cancer cell lines inhibits cell proliferation in response to estrogen and reduces xenografted tumor growth in vivo, suggesting that ERβ might oppose ERα's proliferative effects via formation of ERα/β heterodimers. Despite biochemical and cellular evidence of ERα/β heterodimer formation in cells co-expressing both receptors, the biological roles of the ERα/β heterodimer remain to be elucidated. Here we report the identification of two phytoestrogens that selectively activate ERα/β heterodimers at specific concentrations using a cell-based, two-step high throughput small molecule screen for ER transcriptional activity and ER dimer selectivity. Using ERα/β heterodimer-selective ligands at defined concentrations, we demonstrate that ERα/β heterodimers are growth inhibitory in breast and prostate cells which co-express the two ER isoforms. Furthermore, using Automated Quantitative Analysis (AQUA to examine nuclear expression of ERα and ERβ in human breast tissue microarrays, we demonstrate that ERα and ERβ are co-expressed in the same cells in breast tumors. The co-expression of ERα and ERβ in the same cells supports the possibility of ERα/β heterodimer formation at physio- and pathological conditions, further suggesting that targeting ERα/β heterodimers might be a novel therapeutic approach to the treatment of cancers which co-express ERα and ERβ.

  6. A phase II study of combined ridaforolimus and dalotuzumab compared with exemestane in patients with estrogen receptor-positive breast cancer

    DEFF Research Database (Denmark)

    Baselga, José; Morales, Serafin M.; Awada, Ahmad

    2017-01-01

    Purpose: Combining the mTOR inhibitor ridaforolimus and the anti-IGFR antibody dalotuzumab demonstrated antitumor activity, including partial responses, in estrogen receptor (ER)-positive advanced breast cancer, especially in high proliferation tumors (Ki67 > 15%). Methods: This randomized...

  7. Novel Stromal Biomarkers in Human Breast Cancer Tissues Provide Evidence for the More Malignant Phenotype of Estrogen Receptor-Negative Tumors

    Directory of Open Access Journals (Sweden)

    Zahraa I. Khamis

    2011-01-01

    Full Text Available Research efforts were focused on genetic alterations in epithelial cancer cells. Epithelial-stromal interactions play a crucial role in cancer initiation, progression, invasion, angiogenesis, and metastasis; however, the active role of stroma in human breast tumorigenesis in relation to estrogen receptor (ER status of epithelial cells has not been explored. Using proteomics and biochemical approaches, we identified two stromal proteins in ER-positive and ER-negative human breast cancer tissues that may affect malignant transformation in breast cancer. Two putative biomarkers, T-cell receptor alpha (TCR-α and zinc finger and BRCA1-interacting protein with a KRAB domain (ZBRK1, were detected in leukocytes of ER-positive and endothelial cells of ER-negative tissues, respectively. Our data suggest an immunosuppressive role of leukocytes in invasive breast tumors, propose a multifunctional nature of ZBRK1 in estrogen receptor regulation and angiogenesis, and demonstrate the aggressiveness of ER-negative human breast carcinomas. This research project may identify new stromal drug targets for the treatment of breast cancer patients.

  8. Assessment of the potential activity of major dietary compounds as selective estrogen receptor modulators in two distinct cell models for proliferation and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Lecomte, Sylvain; Lelong, Marie; Bourgine, Gaëlle [Institut de Recherche en Santé-Environnement-Travail (IRSET), Inserm UMR 1085, Team Transcription, Environment and Cancer, University of Rennes 1, 9 Avenue du Pr Léon Bernard, 35000 Rennes (France); Efstathiou, Theo [Laboratoire Nutrinov, Technopole Atalante Champeaux, 8 rue Jules Maillard de la Gournerie, 35012 Rennes Cedex (France); Saligaut, Christian [Institut de Recherche en Santé-Environnement-Travail (IRSET), Inserm UMR 1085, Team Transcription, Environment and Cancer, University of Rennes 1, 9 Avenue du Pr Léon Bernard, 35000 Rennes (France); Pakdel, Farzad, E-mail: farzad.pakdel@univ-rennes1.fr [Institut de Recherche en Santé-Environnement-Travail (IRSET), Inserm UMR 1085, Team Transcription, Environment and Cancer, University of Rennes 1, 9 Avenue du Pr Léon Bernard, 35000 Rennes (France)

    2017-06-15

    Estrogen receptors (ERs) α and β are distributed in most tissues of women and men. ERs are bound by estradiol (E2), a natural hormone, and mediate the pleiotropic and tissue-specific effects of E2, such as proliferation of breast epithelial cells or protection and differentiation of neuronal cells. Numerous environmental molecules, called endocrine disrupting compounds, also interact with ERs. Phytoestrogens belong to this large family and are considered potent therapeutic molecules that act through their selective estrogen receptor modulator (SERM) activity. Using breast cancer cell lines as a model of estrogen-dependent proliferation and a stably ER-expressing PC12 cell line as a model of neuronal differentiating cells, we studied the SERM activity of major dietary compounds, such as apigenin, liquiritigenin, daidzein, genistein, coumestrol, resveratrol and zearalenone. The ability of these compounds to induce ER-transactivation and breast cancer cell proliferation and enhance Nerve Growth Factor (NGF) -induced neuritogenesis was assessed. Surprisingly, although all compounds were able to activate the ER through an estrogen responsive element reporter gene, they showed differential activity toward proliferation or differentiation. Apigenin and resveratrol showed a partial or no proliferative effect on breast cancer cells but fully contributed to the neuritogenesis effect of NGF. However, daidzein and zearalenone showed full effects on cellular proliferation but did not induce cellular differentiation. In summary, our results suggest that the therapeutic potential of phytoestrogens can diverge depending on the molecule and the phenotype considered. Hence, apigenin and resveratrol might be used in the development of therapeutics for breast cancer and brain diseases. - Highlights: • SERM activity of dietary compounds on proliferation and differentiation is studied. • All the dietary compounds tested transactivate estrogen receptors. • Apigenin and

  9. Delta(9)-tetrahydrocannabinol inhibits 17beta-estradiol-induced proliferation and fails to activate androgen and estrogen receptors in MCF7 human breast cancer cells.

    Science.gov (United States)

    von Bueren, A O; Schlumpf, M; Lichtensteiger, W

    2008-01-01

    Delta(9)-tetrahydrocannabinol (THC) exerts palliative effects in cancer patients, but produces adverse effects on the endocrine and reproductive systems. Experimental evidence concerning such effects is controversial. Whether THC exhibits estrogenic or androgenic activity in vitro was investigated. Estrogenic effects of THC were analyzed in vitro by measuring the proliferation of estrogen-sensitive MCF7 cells. Androgenic activity was investigated by the A-Screen assay that measures androgen-dependent inhibition of proliferation of the androgen receptor (AR)-positive human mammary carcinoma cell line, MCF7-AR1. In contrast to 17beta-estradiol, included as positive control with an EC50 value (concentration required for 50% of maximal 17beta-estradiol-induced proliferation) of 1.00 x 10(-12) M, THC failed to induce cell proliferation in the MCF7 cell line at concentrations between 10(-13) and 10(-4) M. THC inhibited 17beta-estradiol-induced proliferation in wild-type MCF7 and MCF7-AR1 cells, with an IC50 value of 2.6 x 10(-5) M and 9 x 10(-6) M, respectively. THC failed to act as an estrogen, but antagonized 17beta-estradiol-induced proliferation. This effect was independent of the AR expression level.

  10. Agonistic activity of tamoxifen, a selective estrogen-receptor modulator (SERM), on arthritic ovariectomized mice

    Science.gov (United States)

    Silva, L.A.S.; Felix, F.B.; Araujo, J.M.D.; Souza, E.V.; Camargo, E.A.; Grespan, R.

    2017-01-01

    Arthritis is positively associated with the decline of sex hormones, especially estrogen. Tamoxifen (TMX) is a selective estrogen receptor modulator, possessing agonist or antagonistic activity in different tissues. Thus, the objective of this study was to investigate the effect of TMX on the zymosan-induced arthritis model. Female Swiss normal and ovariectomized (OVX) mice were divided into groups and treated for five days with TMX (0.3, 0.9 or 2.7 mg/kg) or 17-β-estradiol (E2, 50 µg/kg). On the fifth day, arthritis was induced and 4 h later, leukocyte migration into joint cavities was evaluated. The neutrophil migration in OVX animals, but not in normal mice, treated with TMX (all tested doses) was significantly decreased compared with mice that received the vehicle (P≤0.05). Similarly, this effect was also demonstrated in the E2-treated group. Therefore, the present study demonstrates that TMX presented agonist effects in inhibiting neutrophil migration and preventing arthritis progression in OVX mice. PMID:29160416

  11. Exogenous estrogen as mediator of racial differences in bioactive insulin-like growth factor-I levels among postmenopausal women.

    Science.gov (United States)

    Jung, Su Yon; Vitolins, Mara Z; Paskett, Electra D; Chang, Shine

    2015-04-01

    The role of exogenous estrogen use in racial differences in insulin-like growth factor-I (IGF-I) levels which affect cancer risk is unclear. We investigated whether the relationship between race and circulating bioactive IGF-I proteins was mediated by exogenous estrogen and the extent to which exogenous estrogen influenced the race-IGF-I relationship in postmenopausal women. This cross-sectional study included 636 white and 133 African American postmenopausal women enrolled in an ancillary study of the Women's Health Initiative Observational Study. To assess exogenous estrogen use (nonusers [n = 262] vs users [n = 507]) as a mediator of the race-IGF-I relationship, we used the Baron-Kenny method and an estimation of the proportional change in the odd ratios for IGF-I levels on race plus a bootstrapping test for the significance of the mediation effect. Compared with white women, African American women were more likely to have high IGF-I levels and less likely to use exogenous estrogen. After accounting for race, estrogen nonusers had higher IGF-I levels than estrogen users did. Among oral contraceptive ever users, exogenous estrogen had a strong mediation effect (67%; p = .018) in the race-IGF-I relationship. In the women with a history of hypertension, exogenous estrogen explained racial differences in IGF-I levels to a modest degree (23%; p = .029). Exogenous estrogen use has a potentially important role in disparities in IGF-I bioactivity between postmenopausal African American and white women. A history of oral contraceptive use and hypertension may be part of the interconnected hormonal pathways related to racial differences in IGF-I levels. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Occurrence of estrogenic effects in sewage and industrial wastewaters in Beijing, China

    International Nuclear Information System (INIS)

    Ma Mei; Rao Kaifeng; Wang Zijian

    2007-01-01

    Estrogenic potencies of the effluents or water samples from wastewater treatment plants (WWTPs), industries and hospitals and some receiving rivers in Beijing city were estimated by using a human estrogen receptor recombinant yeast assay. Estrogenic activity of industrial wastewaters was found to range from 0.1 to 13.3 ng EEQ/L and decreased to the range of 0.03-1.6 ng EEQ/L after treatment. Estrogenic activity in WWTP influent ranged from 0.3 to 1.7 ng EEQ/L and decreased to the range of 0.05-0.5 ng EEQ/L after treatment. In the receiving river waters, the estrogenic effect range was 0.1-4.7 ng EEQ/L. These data suggest that treated industrial effluents and WWTP effluents of concern are not the only source of estrogenic pollution in surface waters in Beijing city. EEQ levels in Beijing river water are likely attributable to untreated municipal and industrial wastewaters discharged directly into the river. - Estrogenic activity in Beijing river water is attributed to direct discharges of untreated municipal and industrial wastewaters

  13. Identification and analysis of novel flavonoid agonists and antagonists for the AH and estrogen receptor

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, B.; Nagy, S.; Rogers, J.; Denison, M. [Dept. of Environmental Toxicology, Univ. of California, Davis (United States); Nantz, M.; Kurth, M.; Springsteel, M. [Dept. of Chemistry, Univ. of California, Davis (United States)

    2004-09-15

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates many of the biological and toxicological effects in a diverse range of species, tissues, and cell types. The most studied effect is induction of gene expression, and, the majority of AhR responsive genes, such as cytochrome P4501A1 (CYP1A1), utilize AhR dependent mechanism of action. While halogenated aromatic hydrocarbons (HAHs) and polycyclic aromatic hydrocarbons (PAHs) are the prototypical ligands of the Ah receptor, it has recently identified that the AhR is activated by a structurally diverse array of hydrophobic natural and synthetic chemicals. Given the structural diversity in AhR ligands, the physiochemical characteristics for high and low affinity ligands seems to be established. Environmental contaminants that can disrupt the endocrine homeostasis of an organism have also gained widespread attention in recent years and numerous chemicals have been identified as having either hormone or anti-hormone properties. However, like the AhR, the structural diversity and characteristics of endocrine disrupters that exert their action via nuclear receptors also seems to be depended on the estrogen receptor (ER). The flavonoids are a diverse family of chemicals commonly found in fruits and vegetables. Members of this family exert cytostatic, apoptotic, anti-inflammatory and anti-angiogenic activities. In addition, several flavonoids are potent modulators of both the expression and activities of specific cytochrome P450 genes/proteins and somel others have estrogenic and antiestrogenic activity. Accordingly flavonoids have attracted attention as possible chemoprotective or chemotherapeutic agents. We have previously developed and analyzed a novel chemical library of flavonoids which contained {proportional_to}200 compounds. The ability of these compounds to activate and/or inhibit AhR- and ER- dependent gene expression was examined by using our recently developed AhR- and ER

  14. Synthesis and evaluation of 17 alpha-(carboranylalkyl)estradiols as ligands for estrogen receptors alpha and beta

    Czech Academy of Sciences Publication Activity Database

    Sedlák, David; Eignerová, Barbara; Dračínský, Martin; Janoušek, Zbyněk; Bartůněk, Petr; Kotora, Martin

    2013-01-01

    Roč. 747, 1.12.2013 (2013), s. 178-183 ISSN 0022-328X R&D Projects: GA MŠk(CZ) LC06070; GA MŠk(CZ) LC06077; GA MŠk LM2011022; GA ČR GA204/09/1905 Institutional support: RVO:68378050 ; RVO:61388963 Keywords : carborane * estradiol * metathesis * estrogen receptor * steroid ligand Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.302, year: 2013

  15. Modulation of hepatocyte growth factor gene expression by estrogen in mouse ovary.

    Science.gov (United States)

    Liu, Y; Lin, L; Zarnegar, R

    1994-09-01

    Hepatocyte growth factor (HGF) is expressed in a variety of tissues and cell types under normal conditions and in response to various stimuli such as tissue injury. In the present study, we demonstrate that the transcription of the HGF gene is stimulated by estrogen in mouse ovary. A single injection of 17 beta-estradiol results in a dramatic and transient elevation of the levels of mouse HGF mRNA. Sequence analysis has found that two putative estrogen responsive elements (ERE) reside at -872 in the 5'-flanking region and at +511 in the first intron, respectively, of the mouse HGF gene. To test whether these ERE elements are responsible for estrogen induction of HGF gene expression, chimeric plasmids containing variable regions of the 5'-flanking sequence of HGF gene and the coding region for chloramphenicol acetyltransferase (CAT) gene were transiently transfected into both human endometrial carcinoma RL 95-2 cells and mouse fibroblast NIH 3T3 cells to assess hormone responsiveness. Transfection results indicate that the ERE elements of the mouse HGF gene can confer estrogen action to either homologous or heterologous promoters. Nuclear protein extracts either from RL95-2 cells transfected with the estrogen receptor expression vector or from mouse liver bound in vitro to ERE elements specifically, as shown by band shift assay. Therefore, our results demonstrate that the HGF gene is transcriptionally regulated by estrogen in mouse ovary; and such regulation is mediated via a direct interaction of the estrogen receptor complex with cis-acting ERE elements identified in the mouse HGF gene.

  16. TIMP1 overexpression mediates resistance of MCF-7 human breast cancer cells to fulvestrant and down-regulates progesterone receptor expression

    DEFF Research Database (Denmark)

    Bjerre, Christina; Vinther, Lena; Belling, Kirstine C.

    2013-01-01

    is associated with endocrine sensitivity. We established a panel of 11 MCF-7 subclones with a wide range of TIMP1 mRNA and protein expression levels. Cells with high expression of TIMP1 versus low TIMP1 displayed significantly reduced sensitivity to the antiestrogen fulvestrant (ICI 182,780, Faslodex®), while......, the effects of fulvestrant, 4-hydroxytamoxifen, or estrogen on estrogen receptor expression were not associated with TIMP1 levels. Gene expression analyses revealed associations between expression of TIMP1 and genes involved in metabolic pathways, epidermal growth factor receptor 1/cancer signaling pathways......, and cell cycle. Gene and protein expression analyses showed no general defects in estrogen receptor signaling except from lack of progesterone receptor expression and estrogen inducibility in clones with high TIMP1. The present study suggests a relation between high expression level of TIMP1 and loss...

  17. Estrogen enhanced cell-cell signalling in breast cancer cells exposed to targeted irradiation

    International Nuclear Information System (INIS)

    Shao, Chunlin; Folkard, Melvyn; Held, Kathryn D; Prise, Kevin M

    2008-01-01

    Radiation-induced bystander responses, where cells respond to their neighbours being irradiated are being extensively studied. Although evidence shows that bystander responses can be induced in many types of cells, it is not known whether there is a radiation-induced bystander effect in breast cancer cells, where the radiosensitivity may be dependent on the role of the cellular estrogen receptor (ER). This study investigated radiation-induced bystander responses in estrogen receptor-positive MCF-7 and estrogen receptor-negative MDA-MB-231 breast cancer cells. The influence of estrogen and anti-estrogen treatments on the bystander response was determined by individually irradiating a fraction of cells within the population with a precise number of helium-3 using a charged particle microbeam. Damage was scored as chromosomal damage measured as micronucleus formation. A bystander response measured as increased yield of micronucleated cells was triggered in both MCF-7 and MDA-MB-231 cells. The contribution of the bystander response to total cell damage in MCF-7 cells was higher than that in MDA-MB-231 cells although the radiosensitivity of MDA-MB-231 was higher than MCF-7. Treatment of cells with 17β-estradiol (E2) increased the radiosensitivity and the bystander response in MCF-7 cells, and the effect was diminished by anti-estrogen tamoxifen (TAM). E2 also increased the level of intracellular reactive oxygen species (ROS) in MCF-7 cells in the absence of radiation. In contrast, E2 and TAM had no influence on the bystander response and ROS levels in MDA-MB-231 cells. Moreover, the treatment of MCF-7 cells with antioxidants eliminated both the E2-induced ROS increase and E2-enhanced bystander response triggered by the microbeam irradiation, which indicates that ROS are involved in the E2-enhanced bystander micronuclei formation after microbeam irradiation. The observation of bystander responses in breast tumour cells may offer new potential targets for radiation

  18. Expression of estrogen receptor α 36 (ESR36) in the hamster ovary throughout the estrous cycle: effects of gonadotropins.

    Science.gov (United States)

    Chakraborty, Prabuddha; Roy, Shyamal K

    2013-01-01

    Estradiol-17β (E) plays an important role in ovarian follicular development. Evidence indicates that some of the effect of E is mediated by the transmembrane estrogen receptor. In this study, we examined the spatio-temporal expression of recently discovered ERα36 (ESR36), a splice variant of Esr1 and a receptor for non-genomic E signaling, in the hamster ovary during the estrous cycle and the role of gonadotropins and ovarian steroid hormones in ESR36 expression. ESR36 expression was high on estrus (D1:0900 h) and declined precipitously by proestrus (D4:0900 h) and remained low up to D4:1600 h. Immunofluorescence findings corroborated immunoblot findings and revealed that ESR36 was expressed only in the cell membrane of both follicular and non-follicular cells, except the oocytes. Ovarian ESR36 was capable of binding to the E-affinity matrix, and have different molecular weight than that of the ESR1 or GPER. Hypophysectomy (Hx) resulted in a marked decline in ESR36 protein levels. FSH and LH, alone or combined, markedly upregulated ESR36 protein in Hx hamsters to the levels observed in D1 hamsters, but neither E nor P had any effect. Inhibition of the gonadotropin surge by phenobarbital treatment on D4:1100 h attenuated ESR36 expression in D1:0900 h ovaries, but the decline was restored by either FSH or LH replacement on D4 afternoon. This is the first report to show that ESR36, which is distinct from ESR1 or GPER is expressed in the plasma membrane of ovarian follicular and non-follicular cells, binds to E and its expression is regulated directly by the gonadotropins. In light of our previous findings, the results suggest that ovarian cells contain at least two distinct membrane estrogen receptors, such as GPER and ESR36, and strongly suggest for a non-genomic action of E regulating ovarian follicular functions.

  19. Expression of estrogen receptor α 36 (ESR36 in the hamster ovary throughout the estrous cycle: effects of gonadotropins.

    Directory of Open Access Journals (Sweden)

    Prabuddha Chakraborty

    Full Text Available Estradiol-17β (E plays an important role in ovarian follicular development. Evidence indicates that some of the effect of E is mediated by the transmembrane estrogen receptor. In this study, we examined the spatio-temporal expression of recently discovered ERα36 (ESR36, a splice variant of Esr1 and a receptor for non-genomic E signaling, in the hamster ovary during the estrous cycle and the role of gonadotropins and ovarian steroid hormones in ESR36 expression. ESR36 expression was high on estrus (D1:0900 h and declined precipitously by proestrus (D4:0900 h and remained low up to D4:1600 h. Immunofluorescence findings corroborated immunoblot findings and revealed that ESR36 was expressed only in the cell membrane of both follicular and non-follicular cells, except the oocytes. Ovarian ESR36 was capable of binding to the E-affinity matrix, and have different molecular weight than that of the ESR1 or GPER. Hypophysectomy (Hx resulted in a marked decline in ESR36 protein levels. FSH and LH, alone or combined, markedly upregulated ESR36 protein in Hx hamsters to the levels observed in D1 hamsters, but neither E nor P had any effect. Inhibition of the gonadotropin surge by phenobarbital treatment on D4:1100 h attenuated ESR36 expression in D1:0900 h ovaries, but the decline was restored by either FSH or LH replacement on D4 afternoon. This is the first report to show that ESR36, which is distinct from ESR1 or GPER is expressed in the plasma membrane of ovarian follicular and non-follicular cells, binds to E and its expression is regulated directly by the gonadotropins. In light of our previous findings, the results suggest that ovarian cells contain at least two distinct membrane estrogen receptors, such as GPER and ESR36, and strongly suggest for a non-genomic action of E regulating ovarian follicular functions.

  20. Intraspecific variation in estrogen receptor alpha and the expression of male sociosexual behavior in two populations of prairie voles.

    Science.gov (United States)

    Cushing, Bruce S; Razzoli, Maria; Murphy, Anne Z; Epperson, Pamela M; Le, Wei-Wei; Hoffman, Gloria E

    2004-08-06

    Estrogen (E) regulates a variety of male sociosexual behaviors. We hypothesize that there is a relationship between the distribution of estrogen receptor alpha (ERalpha) and the degree of male social behavior. To test this hypothesis, ERalpha immunoreactivity (IR) was compared in prairie voles (Microtus ochrogaster) from Illinois (IL), which are highly social, and Kansas (KN), which are less social. The expression of androgen receptors (AR) in males also was compared between populations. The expression of ERalpha and AR were compared in brains from KN and IL males and females using immunocytochemistry (ICC). There were significant intrapopulational differences, with males expressing less ERalpha-IR than females in the medial preoptic area, ventromedial nucleus, ventrolateral portion of the hypothalamus, and bed nucleus of the stria terminalis (BST). IL males also displayed less ERalpha-IR in the medial amygdala (MeA) than IL females. While IL males expressed significantly less ERalpha-IR in the BST and MeA than KN males, there was no difference in AR-IR. Differences in the pattern of ERalpha-IR between KN and IL males were behaviorally relevant, as low levels of testosterone (T) were more effective in restoring sexual activity in castrated KN males than IL males. The lack of difference in AR combined with lower expression of ERalpha-IR in IL males suggests that behavioral differences in response to T are associated with aromatization of T to E and that reduced sensitivity to E may facilitate prosocial behavior in males.

  1. Protective effects of estrogen against vascular calcification via estrogen receptor α-dependent growth arrest-specific gene 6 transactivation

    International Nuclear Information System (INIS)

    Nanao-Hamai, Michiko; Son, Bo-Kyung; Hashizume, Tsuyoshi; Ogawa, Sumito; Akishita, Masahiro

    2016-01-01

    Vascular calcification is one of the major complications of cardiovascular disease and is an independent risk factor for myocardial infarction and cardiac death. Postmenopausal women have a higher prevalence of vascular calcification compared with premenopausal women, suggesting protective effects of estrogen (E2). However, the underlying mechanisms of its beneficial effects remain unclear. In the present study, we examined the inhibitory effects of E2 on vascular smooth muscle cell (VSMC) calcification, and found that growth arrest-specific gene 6 (Gas6), a crucial molecule in vascular calcification, is transactivated by estrogen receptor α (ERα) in response to E2. In human aortic smooth muscle cells, physiological levels of E2 inhibited inorganic phosphate (Pi)-induced calcification in a concentration-dependent manner. This inhibitory effect was significantly abolished by MPP, an ERα-selective antagonist, and ERα siRNA, but not by PHTPP, an ERβ-selective antagonist, and ERβ siRNA, implicating an ERα-dependent action. Apoptosis, an essential process for Pi-induced VSMC calcification, was inhibited by E2 in a concentration-dependent manner and further, MPP abolished this inhibition. Mechanistically, E2 restored the inhibited expression of Gas6 and phospho-Akt in Pi-induced apoptosis through ERα. Furthermore, E2 significantly activated Gas6 transcription, and MPP abrogated this E2-dependent Gas6 transactivation. E2-BSA failed to activate Gas6 transcription and to inhibit Ca deposition in VSMC, suggesting beneficial actions of genomic signaling by E2/nuclear ERα. Taken together, these results indicate that E2 exerts inhibitory effects on VSMC apoptosis and calcification through ERα-mediated Gas6 transactivation. These findings indicate a potential therapeutic strategy for the prevention of vascular calcification, especially in postmenopausal women. - Highlights: • E2 inhibits Pi-induced calcification in vascular smooth muscles cells. • E2 inhibits Pi

  2. Increased Sclerostin Levels after Further Ablation of Remnant Estrogen by Aromatase Inhibitors

    Directory of Open Access Journals (Sweden)

    Wonjin Kim

    2015-03-01

    Full Text Available BackgroundSclerostin is a secreted Wnt inhibitor produced almost exclusively by osteocytes, which inhibits bone formation. Aromatase inhibitors (AIs, which reduce the conversion of steroids to estrogen, are used to treat endocrine-responsive breast cancer. As AIs lower estrogen levels, they increase bone turnover and lower bone mass. We analyzed changes in serum sclerostin levels in Korean women with breast cancer who were treated with an AI.MethodsWe included postmenopausal women with endocrine-responsive breast cancer (n=90; mean age, 57.7 years treated with an AI, and compared them to healthy premenopausal women (n=36; mean age, 28.0 years. The subjects were randomly assigned to take either 5 mg alendronate with 0.5 µg calcitriol (n=46, or placebo (n=44 for 6 months.ResultsPostmenopausal women with breast cancer had significantly higher sclerostin levels compared to those in premenopausal women (27.8±13.6 pmol/L vs. 23.1±4.8 pmol/L, P0.05.ConclusionSerum sclerostin levels increased with absolute deficiency of residual estrogens in postmenopausal women with endocrine-responsive breast cancer who underwent AI therapy with concurrent bone loss.

  3. Genotypes of vitamin D and estrogen receptors in pre and perimenopausal women from Córdoba, Argentina Genotipos de los receptores de vitamina D y de estrógeno en mujeres pre y perimenopáusicas de Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    María Ulla

    2007-02-01

    Full Text Available The aim of this study was to determine the frequency of vitamin D receptor and estrogen receptor genotypes and their relationship with the lumbar spine or femoral neck bone mineral density in healthy pre and perimenopausal women from Córdoba (Argentina and adjacent areas. Genotypes were assessed by restriction fragment length polymorphism-polymerase chain reaction technique. Bsm I and Fok I for vitamin D receptor gene and XbaI and PvuII for estrogen receptor gene were used as restrictases. Two hundred and ten healthy pre and perimenopausal women were recruited and analyzed by age. Calcemia and serum parathyroid hormone did not change, but serum P and b-CrossLaps decreased with age. Femoral neck bone mineral density decreased significantly after 30 years old. Vitamin D receptor and estrogen receptor genotype frequencies were similar to those from other Caucasian women. No association between vitamin D receptor and estrogen receptor genotypes with the lumbar spine or femoral neck bone mineral density has been detected. Analysis of interaction between vitamin D receptor and estrogen receptor genes using covariates such as age, height and body mass index did not show any influence of the combination of those genotypes on bone mineral density. Lifestyle, smoking and alcohol intake had no effect on lumbar spine and femoral neck bone mineral density. To conclude, these data do not support the hypothesis that vitamin D receptor and estrogen receptor genotypes influence on lumbar spine and femoral neck bone mineral density in healthy pre and perimenopausal women from this area of Argentina.El propósito del estudio fue determinar la frecuencia de los genotipos de los receptores de vitamina D y de estrógeno y su relación con la densidad mineral ósea en mujeres sanas pre y perimenopáusicas de la ciudad de Córdoba y alrededores. Los genotipos se determinaron con la técnica de reacción en cadena de la polimerasa y análisis de los polimorfismos de

  4. Overexpression of the E2F target gene CENPI promotes chromosome instability and predicts poor prognosis in estrogen receptor-positive breast cancer.

    Science.gov (United States)

    Thangavelu, Pulari U; Lin, Cheng-Yu; Vaidyanathan, Srividya; Nguyen, Thu H M; Dray, Eloise; Duijf, Pascal H G

    2017-09-22

    During cell division, chromosome segregation is facilitated by the mitotic checkpoint, or spindle assembly checkpoint (SAC), which ensures correct kinetochore-microtubule attachments and prevents premature sister-chromatid separation. It is well established that misexpression of SAC components on the outer kinetochores promotes chromosome instability (CIN) and tumorigenesis. Here, we study the expression of CENP-I, a key component of the HIKM complex at the inner kinetochores, in breast cancer, including ductal, lobular, medullary and male breast carcinomas. CENPI mRNA and protein levels are significantly elevated in estrogen receptor-positive (ER+) but not in estrogen receptor-negative (ER-) breast carcinoma. Well-established prognostic tests indicate that CENPI overexpression constitutes a powerful independent marker for poor patient prognosis and survival in ER+ breast cancer. We further demonstrate that CENPI is an E2F target gene. Consistently, it is overexpressed in RB1 -deficient breast cancers. However, CENP-I overexpression is not purely due to cell cycle-associated expression. In ER+ breast cancer cells, CENP-I overexpression promotes CIN, especially chromosome gains. In addition, in ER+ breast carcinomas the degree of CENPI overexpression is proportional to the level of aneuploidy and CENPI overexpression is one of the strongest markers for CIN identified to date. Our results indicate that overexpression of the inner kinetochore protein CENP-I promotes CIN and forecasts poor prognosis for ER+ breast cancer patients. These observations provide novel mechanistic insights and have important implications for breast cancer diagnostics and potentially therapeutic targeting.

  5. Involvement of Human Estrogen Related Receptor Alpha 1 (hERR Alpha 1) in Breast Cancer and Hormonally Insensitive Disease

    Science.gov (United States)

    2001-08-01

    Identification of a new class of steroid hormone receptors. Nature, 331: 91-94, 1988. 4. Vanacker , J. M ., Pettersson, K., Gustafsson, J. A., and...Lippman, M . E., Thompson, E. B., Simon, R., Barlock, A., Green, L., Huff, K. K., Do, H. M ., Aitken, S. C., and Warren, R. Estrogen receptor status: an...important variable in predicting response to endocrine therapy in metastatic breast cancer. Eur J Cancer, 16: 323-331, 1980. 2. Clark, G. M . and

  6. Estrogenic compounds inhibit gap junctional intercellular communication in mouse Leydig TM3 cells

    International Nuclear Information System (INIS)

    Iwase, Yumiko; Fukata, Hideki; Mori, Chisato

    2006-01-01

    Some estrogenic compounds are reported to cause testicular disorders in humans and/or experimental animals by direct action on Leydig cells. In carcinogenesis and normal development, gap junctional intercellular communication (GJIC) plays an essential role in maintaining homeostasis. In this study, we examine the effects of diethylstilbestrol (DES, a synthetic estrogen), 17β-estradiol (E 2 , a natural estrogen), and genistein (GEN, a phytoestrogen) on GJIC between mouse Leydig TM3 cells using Lucifer yellow microinjection. The three compounds tested produced GJIC inhibition in the TM3 cells after 24 h. Gradually, 10 μM DES began to inhibit GJIC for 24 h and this effect was observed until 72 h. On the other hand, both 20 μM E 2 and 25 μM GEN rapidly inhibited GJIC in 6 h and 2 h, respectively. The effects continued until 24 h, but weakened by 72 h. Furthermore, a combined effect at μM level between DES and E 2 on GJIC inhibition was observed, but not between GEN and E 2 . DES and E 2 showed GJIC inhibition at low dose levels (nearly physiological estrogen levels) after 72 h, but GEN did not. DES-induced GJIC inhibition at 10 pM and 10 μM was completely counteracted by ICI 182,780 (ICl), an estrogen receptor antagonist. On the other hand, the inhibitory effects on GJIC with E 2 (10 pM and 20 μM) and GEN (25 μM) were partially blocked by ICI or calphostin C, a protein kinase C (PKC) inhibitor, and were completely blocked by the combination of ICI and calphostin C. These results demonstrate that DES inhibits GJIC between Leydig cells via the estrogen receptor (ER), and that E 2 and GEN inhibit GJIC via ER and PKC. These estrogenic compounds may have different individual nongenotoxic mechanism including PKC pathway on testicular carcinogenesis or development

  7. Purple sweet potato color attenuates domoic acid-induced cognitive deficits by promoting estrogen receptor-α-mediated mitochondrial biogenesis signaling in mice.

    Science.gov (United States)

    Lu, Jun; Wu, Dong-Mei; Zheng, Yuan-Lin; Hu, Bin; Cheng, Wei; Zhang, Zi-Feng

    2012-02-01

    Recent findings suggest that endoplasmic reticulum stress may be involved in the pathogenesis of domoic acid-induced neurodegeneration. Purple sweet potato color, a class of naturally occurring anthocyanins, has beneficial health and biological effects. Recent studies have also shown that anthocyanins have estrogenic activity and can enhance estrogen receptor-α expression. In this study, we evaluated the effect of purple sweet potato color on cognitive deficits induced by hippocampal mitochondrial dysfunction in domoic acid-treated mice and explored the potential mechanisms underlying this effect. Our results showed that the oral administration of purple sweet potato color to domoic acid-treated mice significantly improved their behavioral performance in a step-through passive avoidance task and a Morris water maze task. These improvements were mediated, at least in part, by a stimulation of estrogen receptor-α-mediated mitochondrial biogenesis signaling and by decreases in the expression of p47phox and gp91phox. Decreases in reactive oxygen species and protein carbonylation were also observed, along with a blockade of the endoplasmic reticulum stress pathway. Furthermore, purple sweet potato color significantly suppressed endoplasmic reticulum stress-induced apoptosis, which prevented neuron loss and restored the expression of memory-related proteins. However, knockdown of estrogen receptor-α using short hairpin RNA only partially blocked the neuroprotective effects of purple sweet potato color in the hippocampus of mice cotreated with purple sweet potato color and domoic acid, indicating that purple sweet potato color acts through multiple pathways. These results suggest that purple sweet potato color could be a possible candidate for the prevention and treatment of cognitive deficits in excitotoxic and other brain disorders. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  8. Expression of estrogen receptor beta in the breast carcinoma of BRCA1 mutation carriers

    International Nuclear Information System (INIS)

    Litwiniuk, Maria M; Rożnowski, Krzysztof; Filas, Violetta; Godlewski, Dariusz D; Stawicka, Małgorzata; Kaleta, Remigiusz; Bręborowicz, Jan

    2008-01-01

    Breast cancers (BC) in women carrying mutations in BRCA1 gene are more frequently estrogen receptor negative than the nonhereditary BC. Nevertheless, tamoxifen has been found to have a protective effect in preventing contralateral tumors in BRCA1 mutation carriers. The identification of the second human estrogen receptor, ERβ, raised a question of its role in hereditary breast cancer. The aim of this study was to assess the frequency of ERα, ERβ, PgR (progesterone receptor) and HER-2 expression in breast cancer patients with mutated BRCA1 gene and in the control group. The study group consisted of 48 women with BRCA1 gene mutations confirmed by multiplex PCR assay. The patients were tested for three most common mutations of BRCA1 affecting the Polish population (5382insC, C61G, 4153delA). Immunostaining for ERα, ERβ and PgR (progesterone receptor) was performed using monoclonal antibodies against ERα, PgR (DakoCytomation), and polyclonal antibody against ERβ (Chemicon). The EnVision detection system was applied. The study population comprised a control group of 120 BC operated successively during the years 1998–99. The results of our investigation showed that BRCA1 mutation carriers were more likely to have ERα-negative breast cancer than those in the control group. Only 14.5% of BRCA1-related cancers were ERα-positive compared with 57.5% in the control group (P < 0.0001). On the contrary, the expression of ERβ protein was observed in 42% of BRCA1-related tumors and in 55% of the control group. An interesting finding was that most hereditary cancers (75% of the whole group) were triple-negative: ERα(-)/PgR(-)/HER-2(-) but almost half of this group (44.4%) showed the expression of ERβ. In the case of BRCA1-associated tumors the expression of ERβ was significantly higher than the expression of ERα. This may explain the effectiveness of tamoxifen in preventing contralateral breast cancer development in BRCA1 mutation carriers

  9. Aberrant Splicing of Estrogen Receptor, HER2, and CD44 Genes in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Kazushi Inoue

    2015-01-01

    Full Text Available Breast cancer (BC is the most common cause of cancer-related death among women under the age of 50 years. Established biomarkers, such as hormone receptors (estrogen receptor [ER]/progesterone receptor and human epidermal growth factor receptor 2 (HER2, play significant roles in the selection of patients for endocrine and trastuzumab therapies. However, the initial treatment response is often followed by tumor relapse with intrinsic resistance to the first-line therapy, so it has been expected to identify novel molecular markers to improve the survival and quality of life of patients. Alternative splicing of pre-messenger RNAs is a ubiquitous and flexible mechanism for the control of gene expression in mammalian cells. It provides cells with the opportunity to create protein isoforms with different, even opposing, functions from a single genomic locus. Aberrant alternative splicing is very common in cancer where emerging tumor cells take advantage of this flexibility to produce proteins that promote cell growth and survival. While a number of splicing alterations have been reported in human cancers, we focus on aberrant splicing of ER , HER2 , and CD44 genes from the viewpoint of BC development. ERα36 , a splice variant from the ER1 locus, governs nongenomic membrane signaling pathways triggered by estrogen and confers 4-hydroxytamoxifen resistance in BC therapy. The alternative spliced isoform of HER2 lacking exon 20 (Δ16HER2 has been reported in human BC; this isoform is associated with transforming ability than the wild-type HER2 and recapitulates the phenotypes of endocrine therapy-resistant BC. Although both CD44 splice isoforms ( CD44s , CD44v play essential roles in BC development, CD44v is more associated with those with favorable prognosis, such as luminal A subtype, while CD44s is linked to those with poor prognosis, such as HER2 or basal cell subtypes that are often metastatic. Hence, the detection of splice variants from these loci

  10. The effects of 17β-estradiol and a selective estrogen receptor modulator, bazedoxifene, on ovarian carcinogenesis.

    Science.gov (United States)

    Romero, Iris L; Lee, WooSeok; Mitra, Anirban K; Gordon, Ilyssa O; Zhao, Yan; Leonhardt, Payton; Penicka, Carla V; Mui, Keeley L; Krausz, Thomas N; Greene, Geoffrey L; Lengyel, Ernst

    2012-01-01

    To test if estrogen promotes carcinogenesis in vitro and in a genetic mouse model of ovarian cancer and whether its effects can be inhibited by a novel selective estrogen receptor modulator (SERM), bazedoxifene. Bazedoxifene was synthesized and it was confirmed that the drug abrogated the uterine stimulatory effect of 17β-estradiol in mice. To determine if hormones alter tumorigenesis in vivo LSL-K-ras(G12D/+)Pten(loxP/loxP) mice were treated with vehicle control, 17β-estradiol or bazedoxifene. Hormone receptor status of a cell line established from LSL-K-ras(G12D/+)Pten(loxP/loxP) mouse ovarian tumors was characterized using Western blotting and immunohistochemistry. The cell line was treated with hormones and invasion assays were performed using Boyden chambers and proliferation was assessed using MTT assays. In vitro 17β-estradiol increased both the invasion and proliferation of ovarian cancer cells and bazedoxifene reversed these effects. However, in the genetic mouse model neither treatment with 17β-estradiol nor bazedoxifene changed mean tumor burden when compared to treatment with placebo. The mice in all treatment groups had similar tumor incidence, metastatic nodules and ascites. While 17β-estradiol increases the invasion and proliferation of ovarian cancer cells, these effects do not translate into increased tumor burden in a genetic mouse model of endometrioid ovarian cancer. Likewise, while the SERM reversed the detrimental effects of estrogen in vitro, there was no change in tumor burden in mice treated with bazedoxifene. These findings demonstrate the complex interplay between hormones and ovarian carcinogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Association with replication between estrogen-related receptor gamma (ESRRgamma) polymorphisms and bone phenotypes in women of European ancestry.

    Science.gov (United States)

    Elfassihi, Latifa; Giroux, Sylvie; Bureau, Alexandre; Laflamme, Nathalie; Cole, David Ec; Rousseau, François

    2010-04-01

    Osteoporosis is a bone disease characterized by low bone mineral density (BMD), a highly heritable polygenic trait. Women are more prone than men to develop osteoporosis owing to a lower peak bone mass and accelerated bone loss at menopause. Lack of estrogen thus is a major risk factor for osteoporosis. In addition to having strong similarity to the estrogen receptor 1 (ESR1), the orphan nuclear estrogen-related receptor gamma (ESRRgamma) is widely expressed and shows overlap with ESR1 expression in tissues where estrogen has important physiologic functions. For these reasons, we have undertaken a study of ESRRgamma sequence variants in association with bone measurements [heel quantitative ultrasound (QUS) by measurements of broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) and dual-energy X-ray absorptiometry (DXA) at the femoral neck (FN) and lumbar spine (LS)]. A silent variant was found to be associated with multiple bone measurements (LS, BUA, SOS, and SI), the p values ranging from .006 to .04 in a sample of 5144 Quebec women. The region of this variant was analyzed using the HapMap database and the Gabriel method to define a block of 20 kb. Using the Tagger method, eight TagSNPs were identified and genotyped in a sample of 1335 women. Four of these SNPs capture the five major block haplotypes. One SNP (rs2818964) and one haplotype were significantly associated with multiple bone measures. All SNPs involved in the associations were analyzed in two other sample sets with significant results in the same direction. These results suggest involvement of ESRRgamma in the determination of bone density in women. Copyright 2010 American Society for Bone and Mineral Research.

  12. Association Between a Germline OCA2 Polymorphism at Chromosome 15q13.1 and Estrogen Receptor-Negative Breast Cancer Survival

    DEFF Research Database (Denmark)

    Azzato, E.M.; Tyrer, J.; Fasching, P.A.

    2010-01-01

    -sided. In the hypothesis-generating dataset, SNP rs4778137 (C > G) of the OCA2 gene at 15q13.1 was statistically significantly associated with overall survival among patients with estrogen receptor-negative tumors, with the rare G allele being associated with increased overall survival (HR of death per rare allele carried...... = 0.56, 95% confidence interval [CI] = 0.41 to 0.75, P = 9.2 x 10(-5)). This association was also observed in the validation dataset (HR of death per rare allele carried = 0.88, 95% CI = 0.78 to 0.99, P = .03) and in the combined dataset (HR of death per rare allele carried = 0.82, 95% CI = 0.73 to 0.......92, P = 5 x 10(-4)). The rare G allele of the OCA2 polymorphism, rs4778137, may be associated with improved overall survival among patients with estrogen receptor-negative breast cancer...

  13. QSAR Classification of ToxCast and Tox21 Chemicals on the Basis of Estrogen Receptor Assays (FutureToxII)

    Science.gov (United States)

    The ToxCast and Tox21 programs have tested ~8,200 chemicals in a broad screening panel of in vitro high-throughput screening (HTS) assays for estrogen receptor (ER) agonist and antagonist activity. The present work uses this large in vitro data set to develop in silico QSAR model...

  14. 20180416 - Retrofitting an Estrogen Receptor Transactivation Assay with Metabolic Competence Using Alginate Immobilization of Metabolic Enzymes (AIME) (SETAC HTS)

    Science.gov (United States)

    The VM7Luc4E2 estrogen receptor (ER) transactivation assay is an OECD approved method (TG 457) for the detection of ER agonists and antagonists, and is also part of the Tox21 high-throughput screening (HTS) portfolio. Despite international acceptance as a screening assay, immorta...

  15. The selective estrogen receptor alpha agonist Org 37663 induces estrogenic effects but lacks antirheumatic activity: a phase IIa trial investigating efficacy and safety of Org 37663 in postmenopausal female rheumatoid arthritis patients receiving stable background methotrexate or sulfasalazine.

    Science.gov (United States)

    van Vollenhoven, Ronald F; Houbiers, Jos G A; Buttgereit, Frank; In 't Hout, Joanna; Boers, Maarten; Leij, Susanne; Kvien, Tore K; Dijkmans, Ben A C; Szczepański, Leszek; Szombati, Istvan; Sierakowski, Stanislaw; Miltenburg, André M M

    2010-02-01

    Multiple lines of evidence suggest that sex hormones may play a role in the pathogenesis or clinical expression of rheumatoid arthritis (RA). Studies on the effects of exogenous estrogens in RA patients have yielded contradictory results. We undertook this study to determine the effects of the selective estrogen receptor alpha (ERalpha) agonist Org 37663 in patients with RA, in terms of both its estrogenic effects and its ability to ameliorate disease activity. A 10-week, multicenter, randomized, double-blind, placebo-controlled, parallel group, dose-finding, proof-of-concept trial was initiated to obtain data on the efficacy and safety of Org 37663 in postmenopausal female patients with RA who were receiving background treatment with either methotrexate or sulfasalazine. Patients were randomized to receive placebo or Org 37663 at doses of 4 mg/day, 15 mg/day, or 50 mg/week. The primary efficacy variable was the Disease Activity Score in 28 joints (DAS28). Org 37663 induced a clear biologic, estrogenic response in several organ systems, including a dose-related increase in levels of sex hormone binding globulin. However, the DAS28 decreased similarly for all treatment groups including placebo, indicating lack of clinical efficacy of Org 37663 in this trial. The observed lack of clinical benefit in RA patients treated with an ERalpha agonist, in association with a clear biologic response to the study drug, provides evidence that a biologically relevant ERalpha-mediated estrogenic effect is not associated with a clinically relevant effect on RA symptoms and signs.

  16. Mechanical stimulation enhanced estrogen receptor expression and callus formation in diaphyseal long bone fracture healing in ovariectomy-induced osteoporotic rats.

    Science.gov (United States)

    Chow, S K H; Leung, K S; Qin, J; Guo, A; Sun, M; Qin, L; Cheung, W H

    2016-10-01

    Estrogen receptor (ER) in ovariectomy-induced osteoporotic fracture was reported to exhibit delayed expression. Mechanical stimulation enhanced ER-α expression in osteoporotic fracture callus at the tissue level. ER was also found to be required for the effectiveness of vibrational mechanical stimulation treatment in osteoporotic fracture healing. Estrogen receptor(ER) is involved in mechanical signal transduction in bone metabolism. Its expression was reported to be delayed in osteoporotic fracture healing. The purpose of this study was to investigate the roles played by ER during osteoporotic fracture healing enhanced with mechanical stimulation. Ovariectomy-induced osteoporotic SD rats that received closed femoral fractures were divided into five groups, (i) SHAM, (ii) SHAM-VT, (iii) OVX, (iv) OVX-VT, and (v) OVX-VT-ICI, where VT stands for whole-body vibration treatment and ICI for ER antagonization by ICI 182,780. Callus formation and gene expression were assessed at 2, 4, and 8 weeks postfracture. In vitro osteoblastic differentiation, mineralization, and ER-α expression were assessed. The delayed ER expression was found to be enhanced by vibration treatment. Callus formation enhancement was shown by callus morphometry and micro-CT analysis. Enhancement effects by vibration were partially abolished when ER was modulated by ICI 182,780, in terms of callus formation capacity at 2-4 weeks and ER gene and protein expression at all time points. In vitro, ER expression in osteoblasts was not enhanced by VT treatment, but osteoblastic differentiation and mineralization were enhanced under estrogen-deprived condition. When osteoblastic cells were modulated by ICI 182,780, enhancement effects of VT were eliminated. Vibration was able to enhance ER expression in ovariectomy-induced osteoporotic fracture healing. ER was essential in mechanical signal transduction and enhancement in callus formation effects during osteoporotic fracture healing enhanced by vibration

  17. Flightless I (Drosophila) homolog facilitates chromatin accessibility of the estrogen receptor α target genes in MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kwang Won, E-mail: kwjeong@gachon.ac.kr

    2014-04-04

    Highlights: • H3K4me3 and Pol II binding at TFF1 promoter were reduced in FLII-depleted MCF-7 cells. • FLII is required for chromatin accessibility of the enhancer of ERalpha target genes. • Depletion of FLII causes inhibition of proliferation of MCF-7 cells. - Abstract: The coordinated activities of multiple protein complexes are essential to the remodeling of chromatin structure and for the recruitment of RNA polymerase II (Pol II) to the promoter in order to facilitate the initiation of transcription in nuclear receptor-mediated gene expression. Flightless I (Drosophila) homolog (FLII), a nuclear receptor coactivator, is associated with the SWI/SNF-chromatin remodeling complex during estrogen receptor (ER)α-mediated transcription. However, the function of FLII in estrogen-induced chromatin opening has not been fully explored. Here, we show that FLII plays a critical role in establishing active histone modification marks and generating the open chromatin structure of ERα target genes. We observed that the enhancer regions of ERα target genes are heavily occupied by FLII, and histone H3K4me3 and Pol II binding induced by estrogen are decreased in FLII-depleted MCF-7 cells. Furthermore, formaldehyde-assisted isolation of regulatory elements (FAIRE)-quantitative polymerase chain reaction (qPCR) experiments showed that depletion of FLII resulted in reduced chromatin accessibility of multiple ERα target genes. These data suggest FLII as a key regulator of ERα-mediated transcription through its role in regulating chromatin accessibility for the binding of RNA Polymerase II and possibly other transcriptional coactivators.

  18. Flightless I (Drosophila) homolog facilitates chromatin accessibility of the estrogen receptor α target genes in MCF-7 breast cancer cells

    International Nuclear Information System (INIS)

    Jeong, Kwang Won

    2014-01-01

    Highlights: • H3K4me3 and Pol II binding at TFF1 promoter were reduced in FLII-depleted MCF-7 cells. • FLII is required for chromatin accessibility of the enhancer of ERalpha target genes. • Depletion of FLII causes inhibition of proliferation of MCF-7 cells. - Abstract: The coordinated activities of multiple protein complexes are essential to the remodeling of chromatin structure and for the recruitment of RNA polymerase II (Pol II) to the promoter in order to facilitate the initiation of transcription in nuclear receptor-mediated gene expression. Flightless I (Drosophila) homolog (FLII), a nuclear receptor coactivator, is associated with the SWI/SNF-chromatin remodeling complex during estrogen receptor (ER)α-mediated transcription. However, the function of FLII in estrogen-induced chromatin opening has not been fully explored. Here, we show that FLII plays a critical role in establishing active histone modification marks and generating the open chromatin structure of ERα target genes. We observed that the enhancer regions of ERα target genes are heavily occupied by FLII, and histone H3K4me3 and Pol II binding induced by estrogen are decreased in FLII-depleted MCF-7 cells. Furthermore, formaldehyde-assisted isolation of regulatory elements (FAIRE)-quantitative polymerase chain reaction (qPCR) experiments showed that depletion of FLII resulted in reduced chromatin accessibility of multiple ERα target genes. These data suggest FLII as a key regulator of ERα-mediated transcription through its role in regulating chromatin accessibility for the binding of RNA Polymerase II and possibly other transcriptional coactivators

  19. Projections from estrogen receptor-alpha immunoreactive neurons in the periaqueductal gray to the lateral medulla oblongata in the rhesus monkey

    NARCIS (Netherlands)

    Vanderhorst, VGJM; Terasawa, E; Ralston, HJ

    2004-01-01

    The periaqueductal gray (PAG) contains numerous estrogen receptor-alpha immunoreactive (ER-alpha IR) neurons that are distributed in a species-specific way. These neurons might modulate different types of behavior that are mediated by the PAG such as active and passive coping responses, analgesia,

  20. Role of Estrogens in the Size of Neuronal Somata of Paravaginal Ganglia in Ovariectomized Rabbits

    Directory of Open Access Journals (Sweden)

    Laura G. Hernández-Aragón

    2017-01-01

    Full Text Available We aimed to determine the role of estrogens in modulating the size of neuronal somata of paravaginal ganglia. Rabbits were allocated into control (C, ovariectomized (OVX, and OVX treated with estradiol benzoate (OVX + EB groups to evaluate the neuronal soma area; total serum estradiol (E2 and testosterone (T levels; the percentage of immunoreactive (ir neurons anti-aromatase, anti-estrogen receptor (ERα, ERβ and anti-androgen receptor (AR; the intensity of the immunostaining anti-glial cell line-derived neurotrophic factor (GDNF and the GDNF family receptor alpha type 1 (GFRα1; and the number of satellite glial cells (SGCs per neuron. There was a decrease in the neuronal soma size for the OVX group, which was associated with low T, high percentages of aromatase-ir and neuritic AR-ir neurons, and a strong immunostaining anti-GDNF and anti-GFRα1. The decrease in the neuronal soma size was prevented by the EB treatment that increased the E2 without affecting the T levels. Moreover, there was a high percentage of neuritic AR-ir neurons, a strong GDNF immunostaining in the SGC, and an increase in the SGCs per neuron. Present findings show that estrogens modulate the soma size of neurons of the paravaginal ganglia, likely involving the participation of the SGC.

  1. The role of estrogen in bone growth and formation: changes at puberty

    Directory of Open Access Journals (Sweden)

    Divya Singh

    2010-12-01

    Full Text Available Divya Singh1, Sabyasachi Sanyal2, Naibedya Chattopadhyay11Division of Endocrinology, 2Division of Drug Target Discovery and Development, Central Drug Research Institute (Council of Scientific and Industrial Research, Lucknow, Uttar Pradesh, IndiaAbstract: A high peak bone mass (PBM at skeletal maturity is a good predictor for lower rate of fracture risks in later life. Growth during puberty contributes significantly to PBM achievement in women and men. The growth hormone (GH/insulin-like growth factor 1 (IGF-1 axis has a critical role in pubertal bone growth. There is an increase in GH and IGF-1 levels during puberty; thus, it is assumed that sex steroids contribute to higher GH/IGF-1 action during growth. Recent studies indicate that estrogen increases GH secretion in boys and girls, and the major effect of testosterone on GH secretion is via aromatization to estrogen. Estrogen is pivotal for epiphyseal fusion in young men and women. From studies of individuals with a mutated aromatase gene and a case study of male patient with defective estrogen receptor-alpha (ER-α, it is clear that estrogen is indispensable for normal pubertal growth and growth plate fusion. ER-α and estrogen receptor-beta (ER-β have been localized in growth plate and bone. ER knockout studies have shown that ER-α-/- female mice have reduced linear appendicular growth, while ER-β-/- mice have increased appendicular growth. No such effect is seen in ER-β-/- males; however, repressed growth is seen in ER-α-/- males, resulting in shorter long bones. Thus, ER-β represses longitudinal bone growth in female mice, while it has no function in the regulation of longitudinal bone growth in male mice. These findings indicate that estrogen plays a critical role in skeletal physiology of males as well as females.Keywords: peak bone mass, puberty, estrogen, growth plate

  2. Differential expression of largemouth bass (Micropterus salmoides) estrogen receptor isotypes alpha, beta, and gamma by estradiol.

    Science.gov (United States)

    Sabo-Attwood, Tara; Kroll, Kevin J; Denslow, Nancy D

    2004-04-15

    The expression levels of three estrogen receptor (ER) isotypes alpha, beta, and gamma were quantified in female largemouth bass (Micropterus salmoides) (LMB) liver, ovary, brain, and pituitary tissues. ER alpha and beta expression predominated in the liver, while ERs beta and gamma predominated in the other tissues. Temporally in females, ER alpha was highly up-regulated, ER gamma was slightly up-regulated, and ER beta levels remained unchanged in the liver when plasma 17-beta estradiol (E2) and vitellogenin (Vtg) levels were elevated in the spring. In ovarian tissue from these same fish, all three ERs were maximally expressed in the fall, during early oocyte development and prior to peak plasma E2 levels. When males were injected with E2, ER alpha was highly inducible, ER gamma was moderately up-regulated, and ER beta levels were not affected. None of the ER isotypes were induced by E2 in gonadal tissues. These results combined suggest that the ERs themselves are not regulated in the same manner by E2, and furthermore, do not contribute equally to the transcriptional regulation of genes involved in fish reproduction such as Vtg.

  3. Estrogen receptor protein content is different in abdominal than gluteal subcutaneous adipose tissue of overweight-to-obese premenopausal women.

    Science.gov (United States)

    Gavin, Kathleen M; Cooper, Elizabeth E; Hickner, Robert C

    2013-08-01

    Premenopausal women demonstrate a distinctive gynoid body fat distribution and circulating estrogen status is associated with the maintenance of this adiposity patterning. Estrogen's role in modulation of regional adiposity may occur through estrogen receptors (ERs), which are present in human adipose tissue. The purpose of this study was to determine regional differences in the protein content of ERα, ERβ, and the G protein-coupled estrogen receptor (GPER) between the abdominal (AB) and gluteal (GL) subcutaneous adipose tissue of overweight-to-obese premenopausal women. Biopsies of the subcutaneous AB and GL adipose tissue were performed in 15 premenopausal women (7 Caucasian/8 African American, 25.1 ± 1.8 years, BMI 29.5 ± 0.5kg/m(2)). Adipose tissue protein content was measured by western blot analysis and correlation analyses were conducted to assess the relationship between ER protein content and anthropometric indices/body composition measurements. We found that ERα protein was higher in AB than GL (AB 1.0 ± 0.2 vs GL 0.67 ± 0.1 arbitrary units [AU], P=0.02), ERβ protein was higher in GL than AB (AB 0.78 ± 0.12 vs GL 1.3 ± 0.2 AU, P=0.002), ERα/ERβ ratio was higher in AB than GL (AB 1.9 ± 0.4 vs GL 0.58 ± 0.08 AU, P=0.007), and GPER protein content was similar in AB and GL (P=0.80) subcutaneous adipose tissue. Waist-to-hip ratio was inversely related to gluteal ERβ (r(2)=0.315, P=0.03) and positively related to gluteal ERα/ERβ ratio (r(2)=0.406, P=0.01). These results indicate that depot specific ER content may be an important underlying determinant of regional effects of estrogen in upper and lower body adipose tissue of overweight-to-obese premenopausal women. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Hypergravity and estrogen effects on avian anterior pituitary growth hormone and prolactin levels

    Science.gov (United States)

    Fiorindo, R. P.; Negulesco, J. A.

    1980-01-01

    Developing female chicks with fractured right radii were maintained for 14 d at either earth gravity (1 g) or a hypergravity state (2 g). The birds at 1 g were divided into groups which received daily injections of (1) saline, (2) 200 micrograms estrone, and (3) 400 micrograms estrone for 14 d. The 2-g birds were divided into three similarly treated groups. All 2-g birds showed significantly lower body weights than did 1-g birds. Anterior pituitary (AP) glands were excised and analyzed for growth hormone and prolactin content by analytical electrophoresis. The 1-g chicks receiving either dose of daily estrogen showed increased AP growth hormone levels, whereas hypergravity alone did not affect growth hormone content. Chicks exposed to daily estrogen and hypergravity displayed reduced growth hormone levels. AP prolactin levels were slightly increased by the lower daily estrogen dose in 1-g birds, but markedly reduced in birds exposed only to hypergravity. Doubly-treated chicks displayed normal prolactin levels. Reduced growth in 2-g birds might be due, in part, to reduced AP levels of prolactin and/or growth hormone.

  5. Structural characterization of the binding interactions of various endogenous estrogen metabolites with human estrogen receptor α and β subtypes: a molecular modeling study.

    Directory of Open Access Journals (Sweden)

    Pan Wang

    Full Text Available In the present study, we used the molecular docking approach to study the binding interactions of various derivatives of 17β-estradiol (E2 with human estrogen receptor (ER α and β. First, we determined the suitability of the molecular docking method to correctly predict the binding modes and interactions of two representative agonists (E2 and diethylstilbesterol in the ligand binding domain (LBD of human ERα. We showed that the docked structures of E2 and diethylstilbesterol in the ERα LBD were almost exactly the same as the known crystal structures of ERα in complex with these two estrogens. Using the same docking approach, we then characterized the binding interactions of 27 structurally similar E2 derivatives with the LBDs of human ERα and ERβ. While the binding modes of these E2 derivatives are very similar to that of E2, there are distinct subtle differences, and these small differences contribute importantly to their differential binding affinities for ERs. In the case of A-ring estrogen derivatives, there is a strong inverse relationship between the length of the hydrogen bonds formed with ERs and their binding affinity. We found that a better correlation between the computed binding energy values and the experimentally determined logRBA values could be achieved for various A-ring derivatives by re-adjusting the relative weights of the van der Waals interaction energy and the Coulomb interaction energy in computing the overall binding energy values.

  6. Gene expression profiling in Ishikawa cells: A fingerprint for estrogen active compounds

    International Nuclear Information System (INIS)

    Boehme, Kathleen; Simon, Stephanie; Mueller, Stefan O.

    2009-01-01

    Several anthropogenous and naturally occurring substances, referred to as estrogen active compounds (EACs), are able to interfere with hormone and in particular estrogen receptor signaling. EACs can either cause adverse health effects in humans and wildlife populations or have beneficial effects on estrogen-dependent diseases. The aim of this study was to examine global gene expression profiles in estrogen receptor (ER)-proficient Ishikawa plus and ER-deficient Ishikawa minus endometrial cancer cells treated with selected well-known EACs (Diethylstilbestrol, Genistein, Zearalenone, Resveratrol, Bisphenol A and o,p'-DDT). We also investigated the effect of the pure antiestrogen ICI 182,780 (ICI) on the expression patterns caused by these compounds. Transcript levels were quantified 24 h after compound treatment using Illumina BeadChip Arrays. We identified 87 genes with similar expression changes in response to all EAC treatments in Ishikawa plus. ICI lowered the magnitude or reversed the expression of these genes, indicating ER dependent regulation. Apart from estrogenic gene regulation, Bisphenol A, o,p'-DDT, Zearalenone, Genistein and Resveratrol displayed similarities to ICI in their expression patterns, suggesting mixed estrogenic/antiestrogenic properties. In particular, the predominant antiestrogenic expression response of Resveratrol could be clearly distinguished from the other test compounds, indicating a distinct mechanism of action. Divergent gene expression patterns of the phytoestrogens, as well as weaker estrogenic gene expression regulation determined for the anthropogenous chemicals Bisphenol A and o,p'-DDT, warrants a careful assessment of potential detrimental and/or beneficial effects of EACs. The characteristic expression fingerprints and the identified subset of putative marker genes can be used for screening chemicals with an unknown mode of action and for predicting their potential to exert endocrine disrupting effects

  7. Fecal microbial determinants of fecal and systemic estrogens and estrogen metabolites: a cross-sectional study.

    Science.gov (United States)

    Flores, Roberto; Shi, Jianxin; Fuhrman, Barbara; Xu, Xia; Veenstra, Timothy D; Gail, Mitchell H; Gajer, Pawel; Ravel, Jacques; Goedert, James J

    2012-12-21

    High systemic estrogen levels contribute to breast cancer risk for postmenopausal women, whereas low levels contribute to osteoporosis risk. Except for obesity, determinants of non-ovarian systemic estrogen levels are undefined. We sought to identify members and functions of the intestinal microbial community associated with estrogen levels via enterohepatic recirculation. Fifty-one epidemiologists at the National Institutes of Health, including 25 men, 7 postmenopausal women, and 19 premenopausal women, provided urine and aliquots of feces, using methods proven to yield accurate and reproducible results. Estradiol, estrone, 13 estrogen metabolites (EM), and their sum (total estrogens) were quantified in urine and feces by liquid chromatography/tandem mass spectrometry. In feces, β-glucuronidase and β-glucosidase activities were determined by realtime kinetics, and microbiome diversity and taxonomy were estimated by pyrosequencing 16S rRNA amplicons. Pearson correlations were computed for each loge estrogen level, loge enzymatic activity level, and microbiome alpha diversity estimate. For the 55 taxa with mean relative abundance of at least 0.1%, ordinal levels were created [zero, low (below median of detected sequences), high] and compared to loge estrogens, β-glucuronidase and β-glucosidase enzymatic activity levels by linear regression. Significance was based on two-sided tests with α=0.05. In men and postmenopausal women, levels of total urinary estrogens (as well as most individual EM) were very strongly and directly associated with all measures of fecal microbiome richness and alpha diversity (R≥0.50, P≤0.003). These non-ovarian systemic estrogens also were strongly and significantly associated with fecal Clostridia taxa, including non-Clostridiales and three genera in the Ruminococcaceae family (R=0.57-0.70, P=0.03-0.002). Estrone, but not other EM, in urine correlated significantly with functional activity of fecal β-glucuronidase (R=0.36, P=0

  8. Estrogen and oxytocin receptors in the canine corpus luteum during pregnancy and parturition

    Directory of Open Access Journals (Sweden)

    Gisele Almeida Lima Veiga

    2015-02-01

    Full Text Available The expression of genes encoding the receptors for estrogen (ERαmRNA and oxytocin (OTRmRNA was studied in the corpus luteum during pregnancy and parturition in dogs. Real-time PCR was performed to quantify the levels of ERαmRNA and OTRmRNA in the corpus luteum of bitches during Early (up to 20 days of gestation, Mid (20 to 40 days and Late Pregnancy (40 to 60 days, and Parturition (first stage of labor. The corpus luteum expressed mRNA for OTR, however ERα mRNA was not detected. There was a reduction of OTR mRNA expression in the corpus luteum from gestational Day 20 onward, which suggests an important role of OTR mRNA in the mechanism of pregnancy recognition in dogs. We concluded that the expression of OTR mRNA in canine corpus luteum vary over time, which support the idea that the sensitivity and response to hormone therapy can vary along the course of pregnancy and labor. Moreover, the canine CL lacks ERα mRNA expression during pregnancy.

  9. Estrogens regulate the expression of NHERF1 in normal colon during the reproductive cycle of Wistar rats.

    Science.gov (United States)

    Cuello-Carrión, F Darío; Troncoso, Mariana; Guiñazu, Elina; Valdez, Susana R; Fanelli, Mariel A; Ciocca, Daniel R; Kreimann, Erica L

    2010-12-01

    In breast cancer cell lines, the Na(+)/H(+) exchanger regulator factor 1 (NHERF1) gene is regulated at the transcriptional level by estrogens, the protein expression levels correlate with the presence of estrogen receptors and the effect is blocked by anti-estrogens. However, there is limited information regarding the regulation of NHERF1 by estrogens in normal colon tissue. The NHERF1 protein has an important role in the maintenance of the intestine ultrastructure. NHERF1-deficient mice showed defects in the intestinal microvilli as well as molecular alterations in brush border membrane proteins. Here, we have studied the expression of NHERF1 in normal rat colon and uterus during the reproductive cycle of Wistar rats. We found that NHERF1 expression in rat colon during the estral cycle is modified by estrogen levels: higher expression of NHERF1 was observed during the proestrous and estrous stages and lower expression in diestrous 1 when estrogen levels decreased. In uterus, NHERF1 was expressed in the apical region of the luminal epithelium and glands in all stages of the estral cycle, and in both colon and uterus, the expression was independent of the proliferation status. Our results show that NHERF1 expression is regulated by estrogens in colon during the rat estral cycle.

  10. Estrogen-dependent expression of sine oculis homeobox 1 in the mouse uterus during the estrous cycle

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sijeong [Department of Biomedical Science, CHA University, Seongnam-si, Gyeonggi-do 13488 (Korea, Republic of); Kwon, Hwang [Fertility Center of CHA Bundang Medical Center, Seongnam-si, Gyeonggi-do 13496 (Korea, Republic of); Yoon, Hyemin [Department of Biomedical Science, CHA University, Seongnam-si, Gyeonggi-do 13488 (Korea, Republic of); Park, Miseon [Fertility Center of CHA Gangnam Medical Center, Seoul 06135 (Korea, Republic of); Kim, Hye-Ryun; Song, Haengseok [Department of Biomedical Science, CHA University, Seongnam-si, Gyeonggi-do 13488 (Korea, Republic of); Hong, Kwonho, E-mail: kwonho.hong@dankook.ac.kr [Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan-si, Chungcheongnam-do 31116 (Korea, Republic of); Choi, Youngsok, E-mail: youngsokchoi@cha.ac.kr [Department of Biomedical Science, CHA University, Seongnam-si, Gyeonggi-do 13488 (Korea, Republic of); Fertility Center of CHA Gangnam Medical Center, Seoul 06135 (Korea, Republic of)

    2016-04-08

    The sine oculis homeobox 1 (SIX1) is a member of the Six gene family. SIX1 is involved in tissue development by regulating proliferation, apoptosis, and differentiation. However, function of SIX1 in the uterus remains unknown. Here, we found that Six1 expression is regulated along the estrous cycle in mouse uterus. Six1 expression was significantly increased at estrus stage and decreased at the rest of stages. SIX1 is detected in the luminal and glandular epithelium of uterine endometrium at the estrus stage. Estrogen injection increased Six1 expression in the ovariectomized mouse uterus, whereas progesterone had no effect on its expression. Estrogen receptor antagonist inhibited estrogen-induced Six1 expression. Our findings imply that SIX1 may play a role as an important regulator to orchestrate the dynamic of uterine endometrium in response to estrogen level during the estrous cycle. These results will give us a better understanding of uterine biology. - Highlights: • Six1 expression is regulated during the estrous cycle in mouse uterus. • Six1 is highly expressed at the estrus stage of estrous cycle. • SIX1 is detected in luminal/glandular epithelium of the uterus at the estrus stage. • Estrogen stimulates Six1 expression in an estrogen receptor-dependent manner.

  11. Estrogen receptor beta-selective agonists stimulate calcium oscillations in human and mouse embryonic stem cell-derived neurons.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2010-07-01

    Full Text Available Estrogens are used extensively to treat hot flashes in menopausal women. Some of the beneficial effects of estrogens in hormone therapy on the brain might be due to nongenomic effects in neurons such as the rapid stimulation of calcium oscillations. Most studies have examined the nongenomic effects of estrogen receptors (ER in primary neurons or brain slices from the rodent brain. However, these cells can not be maintained continuously in culture because neurons are post-mitotic. Neurons derived from embryonic stem cells could be a potential continuous, cell-based model to study nongenomic actions of estrogens in neurons if they are responsive to estrogens after differentiation. In this study ER-subtype specific estrogens were used to examine the role of ERalpha and ERbeta on calcium oscillations in neurons derived from human (hES and mouse embryonic stem cells. Unlike the undifferentiated hES cells the differentiated cells expressed neuronal markers, ERbeta, but not ERalpha. The non-selective ER agonist 17beta-estradiol (E(2 rapidly increased [Ca2+]i oscillations and synchronizations within a few minutes. No change in calcium oscillations was observed with the selective ERalpha agonist 4,4',4''-(4-Propyl-[1H]-pyrazole-1,3,5-triyltrisphenol (PPT. In contrast, the selective ERbeta agonists, 2,3-bis(4-Hydroxyphenyl-propionitrile (DPN, MF101, and 2-(3-fluoro-4-hydroxyphenyl-7-vinyl-1,3 benzoxazol-5-ol (ERB-041; WAY-202041 stimulated calcium oscillations similar to E(2. The ERbeta agonists also increased calcium oscillations and phosphorylated PKC, AKT and ERK1/2 in neurons derived from mouse ES cells, which was inhibited by nifedipine demonstrating that ERbeta activates L-type voltage gated calcium channels to regulate neuronal activity. Our results demonstrate that ERbeta signaling regulates nongenomic pathways in neurons derived from ES cells, and suggest that these cells might be useful to study the nongenomic mechanisms of estrogenic compounds.

  12. Gender dependent association between perinatal morbidity and estrogen receptor-alpha Pvull polymorphism.

    Science.gov (United States)

    Derzbach, László; Treszl, András; Balogh, Adám; Vásárhelyi, Barna; Tulassay, Tivadar; Rigó J, János

    2005-01-01

    Assuming the importance of estrogen in perinatal physiology, we tested the association of an estrogen receptor-alpha (ER-alpha) gene Pvull pP polymorphism with perinatal morbidity in premature infants. The ER-alpha Pp genotype was determined in 69 low-birth weight (LBW) boys and 72 LBW girls, 86 term boys and 81 term girls. The association between risk factors, genotype, gender and perinatal morbidity was tested with binary logistic regression analysis. Boys carrying "p" allele were at lower risk for necrotizing enterocolitis (OR [95% Cl]: 0.24 [0.07-0.83]) and patent ductus arteriosus (OR [95% Cl]: 0.24 [0.05-0.97]). The carrier state of the "p" allele was associated with a 34-h shorter period of oxygen supplementation on average (P=0.0018). Boys with pp genotype were at greater risk for intraventricular hemorrhage (OR [95% Cl]: 4.39 [1.15-16.82]). No association between ER-alpha Pvull polymorphism and morbidity was present in girls. Since homozygocity for any Pvull alleles (i.e. having PP or pp genotype) increases the risk for at least one of the most common perinatal complications, it is likely that the heterozygous carrier state of Pvull genotypes has a protective effect, which is gender-dependent.

  13. Hypermethylation pattern of ESR and PgR genes and lacking estrogen and progesterone receptors in human breast cancer tumors: ER/PR subtypes.

    Science.gov (United States)

    Pirouzpanah, Saeed; Taleban, Forough-Azam; Mehdipour, Parvin; Sabour, Siamak; Atri, Morteza

    2018-02-14

    The option of endocrine therapy in breast cancer remains conventionally promising. We aimed to investigate how accurately the pattern of hypermethylation at estrogen receptor (ESR) and progesterone receptor (PgR) genes may associate with relative expression and protein status of ER, PR and the combinative phenotype of ER/PR. In this consecutive case-series, we enrolled 139 primary diagnosed breast cancer. Methylation specific PCR was used to assess the methylation status (individual test). Tumor mRNA expression levels were evaluated using real-time RT-PCR. Immunohistochemistry data was used to present hormonal receptor status of a tumor (as test reference). Methylation at ESR1 was comparably frequent in ER-breast tumors (83.0%, PPR- conditions (Cramer's V= 0.44, PPR (77.1%, PPR expressions (55.6%, PPR- (64.4%, PPR-, the hypermethylation of PgRb seem another epigenetic signalling variable actively associate with methylated ESR1 to show lack of ER+/PR+ tumors in breast cancer.

  14. Role of estrogens in anterior pituitary gland remodeling during the estrous cycle.

    Science.gov (United States)

    Zárate, S; Zaldivar, V; Jaita, G; Magri, L; Radl, D; Pisera, D; Seilicovich, A

    2010-01-01

    In this review, we analyze the action of estrogens leading to the remodeling of the anterior pituitary gland, especially during the estrous cycle. Proliferation and death of anterior pituitary cells and especially lactotropes is regulated by estrogens, which act by sensitizing these cells to both mitotic and apoptotic stimuli such as TNF-alpha, FasL and dopamine. During the estrous cycle, the changing pattern of gonadal steroids is thought to modulate both cell proliferation and death in the anterior pituitary gland, estrogens being key players in cell turnover. The mechanisms involved in estrogen-modulated cell renewal in the anterior pituitary gland during the estrous cycle could include an increase in the expression of proapoptotic cytokines as well as the increase in the Bax/Bcl-2 ratio at proestrus, when estrogen levels are highest and a peak of apoptosis, in particular of lactotropes, is evident in this gland. Estrogens exert rapid antimitogenic and proapoptotic actions in the anterior pituitary through membrane-associated estrogen receptors, a mechanism that might also be involved in remodeling of this gland during the estrous cycle. Copyright (c) 2010 S. Karger AG, Basel.

  15. Role of estrogen receptors in the regulation of reactive gliosis

    Directory of Open Access Journals (Sweden)

    Luis Miguel Garcia-Segura

    2015-02-01

    Full Text Available Although estradiol may directly act on neurons to promote neuroprotection in vitro, the participation of other cell types is also necessary to maintain global tissue homeostasis in vivo (Arevalo et al., 2010; Johann and Beyer, 2013; Acaz-Fonseca et al., 2014. Thus, estradiol acts on glial and endothelial cells to maintain the function of the neurovascular unit, regulates gliosis and the inflammatory response of astrocytes and microglia to control neuroinflammation and acts on neurons, astrocytes and oligodendrocytes to maintain the function and propagating properties of neuronal circuits (Garcia-Ovejero et al., 2005; Tapia-Gonzalez et al., 2008; Barrerto et al., 2009; Cerciat et al., 2010; López Rodríguez et al., 2011; Barreto et al., 2014. Glial cells express estrogen receptors (ERs, including ERalpha, ERbeta and G protein-coupled estrogen receptor-1 (GPER (Garcia-Ovjero et al., 2005; Dhandapani and Brann, 2007 and brain injury induces both the synthesis of estradiol in both reactive astrocytes and the expression of ERs in these cells (Garcia-Ovejero et al., 2002. This suggests that astrocytes may play an important role in the neuroprotective actions of estradiol. Indeed, recent studies, using conditional KO mice for ERalpha and ERbeta, have shown that in an experimental model of multiple sclerosis the protective action of estradiol is mediated by ERalpha expressed in astrocytes, but not by ERalpha expressed in neurons or ERbeta expressed in astrocytes or neurons (Spence et al., 2013. ERs in glial cells activate several neuroprotective mechanisms in response to estradiol, including the release of factors that have trophic effects on neurons and other cell types and the control of neuroinflammation, edema and extracellular glutamate levels. Classical ERs associated with the plasma membrane of astrocytes are involved in the estradiol-induced release of transforming growth factor (TGF-beta, through the activation of the PI3K/Akt signaling

  16. Effects of low dose treatment of tributyltin on the regulation of estrogen receptor functions in MCF-7 cells.

    Science.gov (United States)

    Sharan, Shruti; Nikhil, Kumar; Roy, Partha

    2013-06-01

    Endocrine disrupting chemicals are the natural/synthetic compounds which mimic or inhibit the actions of endogenous hormones. Organotin compounds, such as tributyltin (TBT) are typical environmental contaminants and suspected endocrine-disrupting chemical. The present study evaluates the estrogenic potential of this compound in vitro in ER (+) breast adenocarcinoma, MCF-7 cell line. Our data showed that tributyltin chloride (TBTCl) had agonistic activities for estrogen receptor-α (ER-α). Its estrogenic potential was checked using cell proliferation assay, aromatase assay, transactivation assay, and protein expression analysis. Low dose treatment of TBTCl had a proliferative effect on MCF-7 cells and resulted in up-regulation of aromatase enzyme activity and enhanced estradiol production in MCF-7 cells. Immunofluorescence staining showed translocation of ER-α from cytoplasm to nucleus and increased expression of ER-α, 3β-HSD and aromatase on treatment with increasing doses of TBTCl. Further, to decipher the probable signaling pathways involved in its action, the MCF-7 cells were transfected with different pathway dependent luciferase reporter plasmids (CRE, SRE, NF-κB and AP1). A significant increase in CRE and SRE and decrease in NF-κB regulated pathway were observed (ptributyltin genomically and non-genomically augmented estrogen dependent signaling by targeting various pathways. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Pathway Analysis Revealed Potential Diverse Health Impacts of Flavonoids that Bind Estrogen Receptors

    Science.gov (United States)

    Ye, Hao; Ng, Hui Wen; Sakkiah, Sugunadevi; Ge, Weigong; Perkins, Roger; Tong, Weida; Hong, Huixiao

    2016-01-01

    Flavonoids are frequently used as dietary supplements in the absence of research evidence regarding health benefits or toxicity. Furthermore, ingested doses could far exceed those received from diet in the course of normal living. Some flavonoids exhibit binding to estrogen receptors (ERs) with consequential vigilance by regulatory authorities at the U.S. EPA and FDA. Regulatory authorities must consider both beneficial claims and potential adverse effects, warranting the increases in research that has spanned almost two decades. Here, we report pathway enrichment of 14 targets from the Comparative Toxicogenomics Database (CTD) and the Herbal Ingredients’ Targets (HIT) database for 22 flavonoids that bind ERs. The selected flavonoids are confirmed ER binders from our earlier studies, and were here found in mainly involved in three types of biological processes, ER regulation, estrogen metabolism and synthesis, and apoptosis. Besides cancers, we conjecture that the flavonoids may affect several diseases via apoptosis pathways. Diseases such as amyotrophic lateral sclerosis, viral myocarditis and non-alcoholic fatty liver disease could be implicated. More generally, apoptosis processes may be importantly evolved biological functions of flavonoids that bind ERs and high dose ingestion of those flavonoids could adversely disrupt the cellular apoptosis process. PMID:27023590

  18. Pathway Analysis Revealed Potential Diverse Health Impacts of Flavonoids that Bind Estrogen Receptors

    Directory of Open Access Journals (Sweden)

    Hao Ye

    2016-03-01

    Full Text Available Flavonoids are frequently used as dietary supplements in the absence of research evidence regarding health benefits or toxicity. Furthermore, ingested doses could far exceed those received from diet in the course of normal living. Some flavonoids exhibit binding to estrogen receptors (ERs with consequential vigilance by regulatory authorities at the U.S. EPA and FDA. Regulatory authorities must consider both beneficial claims and potential adverse effects, warranting the increases in research that has spanned almost two decades. Here, we report pathway enrichment of 14 targets from the Comparative Toxicogenomics Database (CTD and the Herbal Ingredients’ Targets (HIT database for 22 flavonoids that bind ERs. The selected flavonoids are confirmed ER binders from our earlier studies, and were here found in mainly involved in three types of biological processes, ER regulation, estrogen metabolism and synthesis, and apoptosis. Besides cancers, we conjecture that the flavonoids may affect several diseases via apoptosis pathways. Diseases such as amyotrophic lateral sclerosis, viral myocarditis and non-alcoholic fatty liver disease could be implicated. More generally, apoptosis processes may be importantly evolved biological functions of flavonoids that bind ERs and high dose ingestion of those flavonoids could adversely disrupt the cellular apoptosis process.

  19. Chronic exposure of killifish to a highly polluted environment desensitizes estrogen-responsive reproductive and biomarker genes

    International Nuclear Information System (INIS)

    Bugel, Sean M.; Bonventre, Josephine A.; White, Lori A.; Tanguay, Robert L.; Cooper, Keith R.

    2014-01-01

    Highlights: • Reproductive biomarker genes in Newark Bay killifish are desensitized to estrogen. • Gene desensitization indicates pre-transcriptional effects on estrogen signaling. • Desensitization does not have a metabolic or epigenetic basis (gene methylation). • Modulation of vitellogenin and choriogenin genes correlates with reproductive impacts. • Choriogenin L appears less prone to false negatives and may be a sensitive biomarker. - Abstract: Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish (Fundulus heteroclitus) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen-responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers (vtg1, vtg2, chg H, chg Hm, chg L) in Newark Bay killifish are relatively less sensitive to 17β-estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism (cyp1a, cyp3a30, mdr) and estrogen receptor (ER α, ER βa, ER βb) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β-estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi-chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng

  20. Chronic exposure of killifish to a highly polluted environment desensitizes estrogen-responsive reproductive and biomarker genes

    Energy Technology Data Exchange (ETDEWEB)

    Bugel, Sean M., E-mail: Sean.Bugel@oregonstate.edu [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Bonventre, Josephine A. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); White, Lori A. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States); Tanguay, Robert L. [Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Cooper, Keith R. [Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901 (United States)

    2014-07-01

    Highlights: • Reproductive biomarker genes in Newark Bay killifish are desensitized to estrogen. • Gene desensitization indicates pre-transcriptional effects on estrogen signaling. • Desensitization does not have a metabolic or epigenetic basis (gene methylation). • Modulation of vitellogenin and choriogenin genes correlates with reproductive impacts. • Choriogenin L appears less prone to false negatives and may be a sensitive biomarker. - Abstract: Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish (Fundulus heteroclitus) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen-responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers (vtg1, vtg2, chg H, chg Hm, chg L) in Newark Bay killifish are relatively less sensitive to 17β-estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism (cyp1a, cyp3a30, mdr) and estrogen receptor (ER α, ER βa, ER βb) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β-estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi-chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng