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Sample records for androgen receptor phosphorylation

  1. Mutation of androgen receptor N-terminal phosphorylation site Tyr-267 leads to inhibition of nuclear translocation and DNA binding.

    Directory of Open Access Journals (Sweden)

    Mehmet Karaca

    Full Text Available Reactivation of androgen receptor (AR may drive recurrent prostate cancer in castrate patients. Ack1 tyrosine kinase is overexpressed in prostate cancer and promotes castrate resistant xenograft tumor growth and enhances androgen target gene expression and AR recruitment to enhancers. Ack1 phosphorylates AR at Tyr-267 and possibly Tyr-363, both in the N-terminal transactivation domain. In this study, the role of these phosphorylation sites was investigated by characterizing the phosphorylation site mutants in the context of full length and truncated AR lacking the ligand-binding domain. Y267F and Y363F mutants showed decreased transactivation of reporters. Expression of wild type full length and truncated AR in LNCaP cells increased cell proliferation in androgen-depleted conditions and increased colony formation. However, the Y267F mutant of full length and truncated AR was defective in stimulating cell proliferation. The Y363F mutant was less severely affected than the Y267F mutant. The full length AR Y267F mutant was defective in nuclear translocation induced by androgen or Ack1 kinase. The truncated AR was constitutively localized to the nucleus. Chromatin immunoprecipitation analysis showed that it was recruited to the target enhancers without androgen. The truncated Y267F AR mutant did not exhibit constitutive nuclear localization and androgen enhancer binding activity. These results support the concept that phosphorylation of Tyr-267, and to a lesser extent Tyr-363, is required for AR nuclear translocation and recruitment and DNA binding and provide a rationale for development of novel approaches to inhibit AR activity.

  2. Selective inhibition reveals cyclin-dependent kinase 2 as another kinase that phosphorylates the androgen receptor at serine 81

    Czech Academy of Sciences Publication Activity Database

    Jorda, Radek; Bučková, Zuzana; Řezníčková, Eva; Bouchal, J.; Kryštof, Vladimír

    2018-01-01

    Roč. 1865, č. 2 (2018), s. 354-363 ISSN 0167-4889 R&D Projects: GA MŠk(CZ) LO1204; GA MŠk(CZ) LO1304 Institutional support: RVO:61389030 Keywords : Androgen receptor * Cyclin-dependent kinase * Inhibitor * Phosphorylation * Serine 81 Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 4.521, year: 2016

  3. Androgen insensitivity syndrome: gonadal androgen receptor activity

    International Nuclear Information System (INIS)

    Coulam, C.B.; Graham, M.L.; Spelsberg, T.C.

    1984-01-01

    To determine whether abnormalities of the androgen receptor previously observed in skin fibroblasts from patients with androgen insensitivity syndrome also occur in the gonads of affected individuals, androgen receptor activity in the gonads of a patient with testicular feminization syndrome was investigated. Using conditions for optimal recovery of androgen receptor from human testes established by previous studies, we detected the presence of a high-affinity (dissociation constant . 3.2 X 10(-10) mol/L), low-capacity (4.2 X 10(-12) mol/mg DNA), androgen-binding protein when tritium-labeled R1881 was incubated at 4 degrees C with nuclear extracts from the gonads of control patients or from a patient with testicular feminization syndrome but not when incubated at 37 degrees C. Thus this patient has an androgen receptor with a temperature lability similar to that of receptors from normal persons

  4. Selective androgen receptor modulators: in pursuit of tissue-selective androgens.

    Science.gov (United States)

    Omwancha, Josephat; Brown, Terry R

    2006-10-01

    The androgen receptor mediates the androgenic and anabolic activity of the endogenous steroids testosterone and 5alpha-dihydrotestosterone. Current knowledge of the androgen receptor protein structure, and the molecular mechanisms surrounding the binding properties and activities of agonists and antagonists has led to the design and development of novel nonsteroidal ligands with selected tissue-specific androgen receptor agonist and antagonist activities. The activity of these compounds, termed selective androgen receptor modulators (SARMs), is directed toward the maintenance or enhancement of anabolic effects on bone and muscle with minimal androgenic effects on prostate growth. SARMs are of potential therapeutic value in the treatment of male hypogonadism, osteoporosis, frailty and muscle wasting, burn injury and would healing, anemia, mood and depression, benign prostatic hyperplasia and prostate cancer.

  5. Lestaurtinib inhibits histone phosphorylation and androgen-dependent gene expression in prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Jens Köhler

    Full Text Available BACKGROUND: Epigenetics is defined as heritable changes in gene expression that are not based on changes in the DNA sequence. Posttranslational modification of histone proteins is a major mechanism of epigenetic regulation. The kinase PRK1 (protein kinase C related kinase 1, also known as PKN1 phosphorylates histone H3 at threonine 11 and is involved in the regulation of androgen receptor signalling. Thus, it has been identified as a novel drug target but little is known about PRK1 inhibitors and consequences of its inhibition. METHODOLOGY/PRINCIPAL FINDING: Using a focused library screening approach, we identified the clinical candidate lestaurtinib (also known as CEP-701 as a new inhibitor of PRK1. Based on a generated 3D model of the PRK1 kinase using the homolog PKC-theta (protein kinase c theta protein as a template, the key interaction of lestaurtinib with PRK1 was analyzed by means of molecular docking studies. Furthermore, the effects on histone H3 threonine phosphorylation and androgen-dependent gene expression was evaluated in prostate cancer cells. CONCLUSIONS/SIGNIFICANCE: Lestaurtinib inhibits PRK1 very potently in vitro and in vivo. Applied to cell culture it inhibits histone H3 threonine phosphorylation and androgen-dependent gene expression, a feature that has not been known yet. Thus our findings have implication both for understanding of the clinical activity of lestaurtinib as well as for future PRK1 inhibitors.

  6. Artemisinin disrupts androgen responsiveness of human prostate cancer cells by stimulating the 26S proteasome-mediated degradation of the androgen receptor protein.

    Science.gov (United States)

    Steely, Andrea M; Willoughby, Jamin A; Sundar, Shyam N; Aivaliotis, Vasiliki I; Firestone, Gary L

    2017-10-01

    Androgen receptor (AR) expression and activity is highly linked to the development and progression of prostate cancer and is a target of therapeutic strategies for this disease. We investigated whether the antimalarial drug artemisinin, which is a sesquiterpene lactone isolated from the sweet wormwood plant Artemisia annua, could alter AR expression and responsiveness in cultured human prostate cancer cell lines. Artemisinin treatment induced the 26S proteasome-mediated degradation of the receptor protein, without altering AR transcript levels, in androgen-responsive LNCaP prostate cancer cells or PC-3 prostate cancer cells expressing exogenous wild-type AR. Furthermore, artemisinin stimulated AR ubiquitination and AR receptor interactions with the E3 ubiquitin ligase MDM2 in LNCaP cells. The artemisinin-induced loss of AR protein prevented androgen-responsive cell proliferation and ablated total AR transcriptional activity. The serine/threonine protein kinase AKT-1 was shown to be highly associated with artemisinin-induced proteasome-mediated degradation of AR protein. Artemisinin treatment activated AKT-1 enzymatic activity, enhanced receptor association with AKT-1, and induced AR serine phosphorylation. Treatment of LNCaP cells with the PI3-kinase inhibitor LY294002, which inhibits the PI3-kinase-dependent activation of AKT-1, prevented the artemisinin-induced AR degradation. Furthermore, in transfected receptor-negative PC-3 cells, artemisinin failed to stimulate the degradation of an altered receptor protein (S215A/S792A) with mutations in its two consensus AKT-1 serine phosphorylation sites. Taken together, our results indicate that artemisinin induces the degradation of AR protein and disrupts androgen responsiveness of human prostate cancer cells, suggesting that this natural compound represents a new potential therapeutic molecule that selectively targets AR levels.

  7. Androgen Receptor Signaling in Bladder Cancer

    Science.gov (United States)

    Li, Peng; Chen, Jinbo; Miyamoto, Hiroshi

    2017-01-01

    Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer. PMID:28241422

  8. Androgen Receptor Signaling in Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Peng Li

    2017-02-01

    Full Text Available Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer.

  9. Androgen Receptor Signaling in Bladder Cancer

    OpenAIRE

    Li, Peng; Chen, Jinbo; Miyamoto, Hiroshi

    2017-01-01

    Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in u...

  10. Camptothecin disrupts androgen receptor signaling and suppresses prostate cancer cell growth

    International Nuclear Information System (INIS)

    Liu, Shicheng; Yuan, Yiming; Okumura, Yutaka; Shinkai, Norihiro; Yamauchi, Hitoshi

    2010-01-01

    The androgen receptor (AR) is the main therapeutic target for treatment of metastatic prostate cancers. The present study demonstrates that the topoisomerase I inhibitor camptothecin selectively inhibits androgen-responsive growth of prostate cancer cells. Camptothecin strikingly inhibited mutated and wild-type AR protein expression in LNCaP and PC-3/AR cells. This inhibition coincided with decreased androgen-mediated AR phosphorylation at Ser 81 and reduced androgen-mediated AR transcriptional activity in a dose-dependent manner. Additionally, camptothecin disrupted the association between AR and heat shock protein 90 and impeded binding of the synthetic androgen [ 3 H]R1881 to AR in LNCaP cells. Camptothecin also blocked androgen-induced AR nuclear translocation, leading to downregulation of the AR target gene PSA. In addition to decreasing the intracellular and secreted prostate-specific antigen (PSA) levels, camptothecin markedly inhibited androgen-stimulated PSA promoter activity. Collectively, our data reveal that camptothecin not only serves as a traditional genotoxic agent but, by virtue of its ability to target and disrupt AR, may also be a novel candidate for the treatment of prostate cancer.

  11. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Maryam Ghotbaddini

    2015-07-01

    Full Text Available The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR. TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models.

  12. Androgen receptor expression in human ovarian and uterine tissue of long term androgen-treated transsexual women

    NARCIS (Netherlands)

    D. Chadha; T.D. Pache; F.J. Huikeshoven (Frans); A.O. Brinkmann (Albert); Th.H. van der Kwast (Theo)

    1994-01-01

    textabstractAndrogen receptor (AR) modulation in human uteri and ovaries of long term androgen-treated transsexual female patients was investigated. Androgen receptor expression was evaluated immunohistochemically in the ovaries of 11 and the endometria and myometria of six androgen-treated

  13. Androgen signaling promotes translation of TMEFF2 in prostate cancer cells via phosphorylation of the α subunit of the translation initiation factor 2.

    Directory of Open Access Journals (Sweden)

    Ryan F Overcash

    Full Text Available The type I transmembrane protein with epidermal growth factor and two follistatin motifs 2 (TMEFF2, is expressed mainly in brain and prostate. Expression of TMEFF2 is deregulated in prostate cancer, suggesting a role in this disease, but the molecular mechanism(s involved in this effect are not clear. Although androgens promote tmeff2 transcription, androgen delivery to castrated animals carrying CWR22 xenografts increases TMEFF2 protein levels in the absence of mRNA changes, suggesting that TMEFF2 may also be post-transcriptionally regulated. Here we show that translation of TMEFF2 is regulated by androgens. Addition of physiological concentrations of dihydrotestosterone (DHT to prostate cancer cell lines increases translation of endogenous TMEFF2 or transfected TMEFF2-Luciferase fusions, and this effect requires the presence of upstream open reading frames (uORFs in the 5'-untranslated region (5'-UTR of TMEFF2. Using chemical and siRNA inhibition of the androgen receptor (AR, we show that the androgen effect on TMEFF2 translation is mediated by the AR. Importantly, DHT also promotes phosphorylation of the α subunit of the translation initiation factor 2 (eIF2α in an AR-dependent manner, paralleling the effect on TMEFF2 translation. Moreover, endoplasmic reticulum (ER stress conditions, which promote eIF2α phosphorylation, also stimulate TMEFF2 translation. These results indicate that androgen signaling promotes eIF2α phosphorylation and subsequent translation of TMEFF2 via a mechanism that requires uORFs in the 5'-UTR of TMEFF2.

  14. Molecular analysis of the androgen-receptor gene in a family with receptor-positive partial androgen insensitivity: an unusual type of intronic mutation

    NARCIS (Netherlands)

    H.T. Brüggenwirth (Hennie); A.L.M. Boehmer (Annemie); S. Ramnarain; M.C. Verleun-Mooijman; D.P.E. Satijn (David); J. Trapman (Jan); J.A. Grootegoed (Anton); A.O. Brinkmann (Albert)

    1997-01-01

    textabstractIn the coding part and the intron-exon boundaries of the androgen-receptor gene of a patient with partial androgen insensitivity, no mutation was found. The androgen receptor of this patient displayed normal ligand-binding parameters and migrated as a

  15. Androgen receptor drives cellular senescence.

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    Yelena Mirochnik

    Full Text Available The accepted androgen receptor (AR role is to promote proliferation and survival of prostate epithelium and thus prostate cancer progression. While growth-inhibitory, tumor-suppressive AR effects have also been documented, the underlying mechanisms are poorly understood. Here, we for the first time link AR anti-cancer action with cell senescence in vitro and in vivo. First, AR-driven senescence was p53-independent. Instead, AR induced p21, which subsequently reduced ΔN isoform of p63. Second, AR activation increased reactive oxygen species (ROS and thereby suppressed Rb phosphorylation. Both pathways were critical for senescence as was proven by p21 and Rb knock-down and by quenching ROS with N-Acetyl cysteine and p63 silencing also mimicked AR-induced senescence. The two pathways engaged in a cross-talk, likely via PML tumor suppressor, whose localization to senescence-associated chromatin foci was increased by AR activation. All these pathways contributed to growth arrest, which resolved in senescence due to concomitant lack of p53 and high mTOR activity. This is the first demonstration of senescence response caused by a nuclear hormone receptor.

  16. Effect of propofol on androgen receptor activity in prostate cancer cells.

    Science.gov (United States)

    Tatsumi, Kenichiro; Hirotsu, Akiko; Daijo, Hiroki; Matsuyama, Tomonori; Terada, Naoki; Tanaka, Tomoharu

    2017-08-15

    Androgen receptor is a nuclear receptor and transcription factor activated by androgenic hormones. Androgen receptor activity plays a pivotal role in the development and progression of prostate cancer. Although accumulating evidence suggests that general anesthetics, including opioids, affect cancer cell growth and impact patient prognosis, the effect of those drugs on androgen receptor in prostate cancer is not clear. The purpose of this study was to investigate the effect of the general anesthetic propofol on androgen receptor activity in prostate cancer cells. An androgen-dependent human prostate cancer cell line (LNCaP) was stimulated with dihydrotestosterone (DHT) and exposed to propofol. The induction of androgen receptor target genes was investigated using real-time reverse transcription polymerase chain reaction, and androgen receptor protein levels and localization patterns were analyzed using immunoblotting and immunofluorescence assays. The effect of propofol on the proliferation of LNCaP cells was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Propofol significantly inhibited DHT-induced expression of androgen receptor target genes in a dose- and time-dependent manner, and immunoblotting and immunofluorescence assays indicated that propofol suppressed nuclear levels of androgen receptor proteins. Exposure to propofol for 24h suppressed the proliferation of LNCaP cells, whereas 4h of exposure did not exert significant effects. Together, our results indicate that propofol suppresses nuclear androgen receptor protein levels, and inhibits androgen receptor transcriptional activity and proliferation in LNCaP cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Dissecting the roles of the androgen receptor in prostate cancer from molecular perspectives.

    Science.gov (United States)

    Hu, Jieping; Wang, Gongxian; Sun, Ting

    2017-05-01

    Androgen receptor plays a pivotal role in prostate cancer progression, and androgen deprivation therapy to intercept androgen receptor signal pathway is an indispensable treatment for most advanced prostate cancer patients to delay cancer progression. However, the emerging of castration-resistant prostate cancer reminds us the alteration of androgen receptor, which includes androgen receptor mutation, the formation of androgen receptor variants, and androgen receptor distribution in cancer cells. In this review, we introduce the process of androgen receptor and also its variants' formation, translocation, and function alteration by protein modification or interaction with other pathways. We dissect the roles of androgen receptor in prostate cancer from molecular perspective to provide clues for battling prostate cancer, especially castration-resistant prostate cancer.

  18. Androgen receptor expression in human ovarian and uterine tissue of long term androgen-treated transsexual women

    OpenAIRE

    Chadha, D.; Pache, T.D.; Huikeshoven, Frans; Brinkmann, Albert; Kwast, Theo

    1994-01-01

    textabstractAndrogen receptor (AR) modulation in human uteri and ovaries of long term androgen-treated transsexual female patients was investigated. Androgen receptor expression was evaluated immunohistochemically in the ovaries of 11 and the endometria and myometria of six androgen-treated transsexual female patients. This was compared with AR expression in the ovaries and uteri of premenopausal and postmenopausal women not receiving treatment and in 10 ovaries of female patients with polycy...

  19. Steroidal androgens and nonsteroidal, tissue-selective androgen receptor modulator, S-22, regulate androgen receptor function through distinct genomic and nongenomic signaling pathways.

    Science.gov (United States)

    Narayanan, Ramesh; Coss, Christopher C; Yepuru, Muralimohan; Kearbey, Jeffrey D; Miller, Duane D; Dalton, James T

    2008-11-01

    Androgen receptor (AR) ligands are important for the development and function of several tissues and organs. However, the poor oral bioavailability, pharmacokinetic properties, and receptor cross-reactivity of testosterone, coupled with side effects, place limits on its clinical use. Selective AR modulators (SARMs) elicit anabolic effects in muscle and bone, sparing reproductive organs like the prostate. However, molecular mechanisms underlying the tissue selectivity remain ambiguous. We performed a variety of in vitro studies to compare and define the molecular mechanisms of an aryl propionamide SARM, S-22, as compared with dihydrotestosterone (DHT). Studies indicated that S-22 increased levator ani muscle weight but decreased the size of prostate in rats. Analysis of the upstream intracellular signaling events indicated that S-22 and DHT mediated their actions through distinct pathways. Modulation of these pathways altered the recruitment of AR and its cofactors to the PSA enhancer in a ligand-dependent fashion. In addition, S-22 induced Xenopus laevis oocyte maturation and rapid phosphorylation of several kinases, through pathways distinct from steroids. These studies reveal novel differences in the molecular mechanisms by which S-22, a nonsteroidal SARM, and DHT mediate their pharmacological effects.

  20. Cotargeting of Androgen Synthesis and Androgen Receptor Expression as a Novel Treatment for Castration Resistant Prostate Cancer

    Science.gov (United States)

    2017-08-01

    disease [2-4]. The major mechanism underlying the development of CRPC is the reactivation of the androgen receptor (AR), the driver of prostate cancer ...Epigenetic Activator of Androgen Receptor Expression in Castration- Resistant Prostate Cancer . Indiana Basic Urological Research (IBUR) Symposium...principal discipline(s) of the project? Androgen receptor (AR) is the driver of prostate cancer development and progression and is the validated

  1. Discovery and therapeutic promise of selective androgen receptor modulators.

    Science.gov (United States)

    Chen, Jiyun; Kim, Juhyun; Dalton, James T

    2005-06-01

    Androgens are essential for male development and the maintenance of male secondary characteristics, such as bone mass, muscle mass, body composition, and spermatogenesis. The main disadvantages of steroidal androgens are their undesirable physicochemical and pharmacokinetic properties. The recent discovery of nonsteroidal selective androgen receptor modulators (SARMs) provides a promising alternative for testosterone replacement therapies with advantages including oral bioavailability, flexibility of structural modification, androgen receptor specificity, tissue selectivity, and the lack of steroid-related side effects.

  2. Androgen Receptor Splice Variants and Resistance to Taxane Chemotherapy

    Science.gov (United States)

    2017-10-01

    resistant prostate cancer ; docetaxel; cabazitaxel; chemotherapy; androgen receptor splice variants; microtubule; ligand-binding domain; microtubule... receptor splice variants (AR-Vs) are associated with resistance to taxane chemotherapy in castration- resistant prostate cancer (CRPC). However, this...androgen receptor inhibitors in prostate cancer . Nat Rev Cancer . 2015;15:701–11.

  3. A Novel Mechanism of Androgen Receptor Action

    National Research Council Canada - National Science Library

    Roberts, Jr, Charles T

    2006-01-01

    .... Specifically, the authors had determined that the androgen receptor controls the expression of the cell-surface receptor for the hormone IGF-1 at the level of translation of the IGF-1 receptor mRNA...

  4. Androgens as therapy for androgen receptor-positive castration-resistant prostate cancer

    Directory of Open Access Journals (Sweden)

    Lin Hui-Ping

    2011-08-01

    Full Text Available Abstract Prostate cancer is the most frequently diagnosed non-cutaneous tumor of men in Western countries. While surgery is often successful for organ-confined prostate cancer, androgen ablation therapy is the primary treatment for metastatic prostate cancer. However, this therapy is associated with several undesired side-effects, including increased risk of cardiovascular diseases. Shortening the period of androgen ablation therapy may benefit prostate cancer patients. Intermittent Androgen Deprivation therapy improves quality of life, reduces toxicity and medical costs, and delays disease progression in some patients. Cell culture and xenograft studies using androgen receptor (AR-positive castration-resistant human prostate cancers cells (LNCaP, ARCaP, and PC-3 cells over-expressing AR suggest that androgens may suppress the growth of AR-rich prostate cancer cells. Androgens cause growth inhibition and G1 cell cycle arrest in these cells by regulating c-Myc, Skp2, and p27Kip via AR. Higher dosages of testosterone cause greater growth inhibition of relapsed tumors. Manipulating androgen/AR signaling may therefore be a potential therapy for AR-positive advanced prostate cancer.

  5. Three novel and two known androgen receptor gene mutations ...

    Indian Academy of Sciences (India)

    gene mutations associated with androgen insensitivity syndrome in sex-reversed XY female patients. J. Genet. ... signal and a C-terminal. Keywords. androgen insensitivity syndrome; androgen receptor; truncation mutation; N-terminal domain; XY sex reversal. .... and an increased risk of gonadal tumour. Mutations in SRY.

  6. Super-Penetrant Androgen Receptor: Overcoming Enzalutamide Sensitivity in Castration-Resistant Prostate Cancer

    Science.gov (United States)

    2016-07-01

    Prostate Cancer Research Symposium- Prostate Cancer Epigenetic Reprogramming of the Androgen Receptor in Castration Resistant Prostate Cancer , May19... cancer cells rely critically on the androgen receptor (AR) for initiation, growth and progression to castration resistant prostate cancer (CRPC...Androgen receptor, castration resistant prostate cancer , Enzalutamide , kinases. 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER

  7. Orphan nuclear receptor TLX contributes to androgen insensitivity in castration-resistant prostate cancer via its repression of androgen receptor transcription.

    Science.gov (United States)

    Jia, Lin; Wu, Dinglan; Wang, Yuliang; You, Wenxing; Wang, Zhu; Xiao, Lijia; Cai, Ganhui; Xu, Zhenyu; Zou, Chang; Wang, Fei; Teoh, Jeremy Yuen-Chun; Ng, Chi-Fai; Yu, Shan; Chan, Franky L

    2018-03-20

    The metastatic castration-resistant prostate cancer (CRPC) is a lethal form of prostate cancer, in which the expression of androgen receptor (AR) is highly heterogeneous. Indeed, lower AR expression and attenuated AR signature activity is shown in CRPC tissues, especially in the subset of neuroendocrine prostate cancer (NEPC) and prostate cancer stem-like cells (PCSCs). However, the significance of AR downregulation in androgen insensitivity and de-differentiation of tumor cells in CRPC is poorly understood and much neglected. Our previous study shows that the orphan nuclear receptor TLX (NR2E1), which is upregulated in prostate cancer, plays an oncogenic role in prostate carcinogenesis by suppressing oncogene-induced senescence. In the present study, we further established that TLX exhibited an increased expression in metastatic CRPC. Further analyses showed that overexpression of TLX could confer resistance to androgen deprivation and anti-androgen in androgen-dependent prostate cancer cells in vitro and in vivo, whereas knockdown of endogenous TLX could potentiate the sensitivity to androgen deprivation and anti-androgen in prostate cancer cells. Our study revealed that the TLX-induced resistance to androgen deprivation and anti-androgen was mediated through its direct suppression of AR gene transcription and signaling in both androgen-stimulated and -unstimulated prostate cancer cells. We also characterized that TLX could bind directly to AR promoter and repress AR transcription by recruitment of histone modifiers, including HDAC1, HDAC3, and LSD1. Together, our present study shows, for the first time, that TLX can contribute to androgen insensitivity in CRPC via repression of AR gene transcription and signaling, and also implicates that targeting the druggable TLX may have a potential therapeutic significance in CRPC management, particularly in NEPC and PCSCs.

  8. The PPARγ ligand ciglitazone regulates androgen receptor activation differently in androgen-dependent versus androgen-independent human prostate cancer cells

    International Nuclear Information System (INIS)

    Moss, Patrice E.; Lyles, Besstina E.; Stewart, LaMonica V.

    2010-01-01

    The androgen receptor (AR) regulates growth and progression of androgen-dependent as well as androgen-independent prostate cancer cells. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists have been reported to reduce AR activation in androgen-dependent LNCaP prostate cancer cells. To determine whether PPARγ ligands are equally effective at inhibiting AR activity in androgen-independent prostate cancer, we examined the effect of the PPARγ ligands ciglitazone and rosiglitazone on C4-2 cells, an androgen- independent derivative of the LNCaP cell line. Luciferase-based reporter assays and Western blot analysis demonstrated that PPARγ ligand reduced dihydrotestosterone (DHT)-induced increases in AR activity in LNCaP cells. However, in C4-2 cells, these compounds increased DHT-induced AR driven luciferase activity. In addition, ciglitazone did not significantly alter DHT-mediated increases in prostate specific antigen (PSA) protein or mRNA levels within C4-2 cells. siRNA-based experiments demonstrated that the ciglitazone-induced regulation of AR activity observed in C4-2 cells was dependent on the presence of PPARγ. Furthermore, overexpression of the AR corepressor cyclin D1 inhibited the ability of ciglitazone to induce AR luciferase activity in C4-2 cells. Thus, our data suggest that both PPARγ and cyclin D1 levels influence the ability of ciglitazone to differentially regulate AR signaling in androgen-independent C4-2 prostate cancer cells.

  9. Pharmacodynamics of selective androgen receptor modulators.

    Science.gov (United States)

    Yin, Donghua; Gao, Wenqing; Kearbey, Jeffrey D; Xu, Huiping; Chung, Kiwon; He, Yali; Marhefka, Craig A; Veverka, Karen A; Miller, Duane D; Dalton, James T

    2003-03-01

    The present study aimed to identify selective androgen receptor modulators (SARMs) with in vivo pharmacological activity. We examined the in vitro and in vivo pharmacological activity of four chiral, nonsteroidal SARMs synthesized in our laboratories. In the in vitro assays, these compounds demonstrated moderate to high androgen receptor (AR) binding affinity, with K(i) values ranging from 4 to 37 nM, and three of the compounds efficaciously stimulated AR-mediated reporter gene expression. The compounds were then administered subcutaneously to castrated rats to appraise their in vivo pharmacological activity. Androgenic activity was evaluated by the ability of these compounds to maintain the weights of prostate and seminal vesicle, whereas levator ani muscle weight was used as a measure of anabolic activity. The maximal response (E(max)) and dose for half-maximal effect (ED(50)) were determined for each compound and compared with that observed for testosterone propionate (TP). Compounds S-1 and S-4 demonstrated in vivo androgenic and anabolic activity, whereas compounds S-2 and S-3 did not. The activities of S-1 and S-4 were tissue-selective in that both compounds stimulated the anabolic organs more than the androgenic organs. These two compounds were less potent and efficacious than TP in androgenic activity, but their anabolic activity was similar to or greater than that of TP. Neither S-1 nor S-4 caused significant luteinizing hormone or follicle stimulating hormone suppression at doses near the ED(50) value. Thus, compounds S-1 and S-4 were identified as SARMs with potent and tissue-selective in vivo pharmacological activity, and represent the first members of a new class of SARMs with selective anabolic effects.

  10. The liver X receptor agonist T0901317 acts as androgen receptor antagonist in human prostate cancer cells

    International Nuclear Information System (INIS)

    Chuu, Chih-pin; Chen, Rou-Yu; Hiipakka, Richard A.; Kokontis, John M.; Warner, Karen V.; Xiang, Jialing; Liao, Shutsung

    2007-01-01

    T0901317 is a potent non-steroidal synthetic liver X receptor (LXR) agonist. T0901317 blocked androgenic stimulation of the proliferation of androgen-dependent LNCaP 104-S cells and androgenic suppression of the proliferation of androgen-independent LNCaP 104-R2 cells, inhibited the transcriptional activation of an androgen-dependent reporter gene by androgen, and suppressed gene and protein expression of prostate specific antigen (PSA), a target gene of androgen receptor (AR) without affecting gene and protein expression of AR. T0901317 also inhibited binding of a radiolabeled androgen to AR, but inhibition was much weaker compared to the effect of the antiandrogens, bicalutamide and hydroxyflutamide. The LXR agonist T0901317, therefore, acts as an antiandrogen in human prostate cancer cells

  11. A PRACTICAL APPROACH TO THE DETECTION OF ANDROGEN RECEPTOR GENE-MUTATIONS AND PEDIGREE ANALYSIS IN FAMILIES WITH X-LINKED ANDROGEN INSENSITIVITY

    NARCIS (Netherlands)

    RISSTALPERS, C; HOOGENBOEZEM, T; SLEDDENS, HFBM; VERLEUNMOOIJMAN, MCT; DEGENHART, HJ; DROP, SLS; HALLEY, DJJ; Oosterwijk, Jan; HODGINS, MB; TRAPMAN, J; BRINKMANN, AO

    Androgen insensitivity syndrome (AIS) is an X-linked disorder in which defects in the androgen receptor gene have prevented the normal development of both internal and external male structures in 46,XY individuals. This survey reports the analysis of 11 AIS subjects. The androgen receptor gene of

  12. A practical approach to the detection of androgen receptor gene mutations and pedigree analysis in families with x-linked androgen insensitivity

    NARCIS (Netherlands)

    Ris-Stalpers, C.; Hoogenboezem, T.; Sleddens, H. F.; Verleun-Mooijman, M. C.; Degenhart, H. J.; Drop, S. L.; Halley, D. J.; Oosterwijk, J. C.; Hodgins, M. B.; Trapman, J.

    1994-01-01

    Androgen insensitivity syndrome (AIS) is an X-linked disorder in which defects in the androgen receptor gene have prevented the normal development of both internal and external male structures in 46,XY individuals. This survey reports the analysis of 11 AIS subjects. The androgen receptor gene of

  13. Role of Androgen Receptor in Growth of Androgen Independent Prostate Cancer

    National Research Council Canada - National Science Library

    Chen, Charlie

    2003-01-01

    ...) overexpression is the only consistent change in the progression of prostate cancer. In the last grand period, I confirmed by western blot analysis that androgen receptor protein is higher in HR than HS tumors...

  14. The PPAR{gamma} ligand ciglitazone regulates androgen receptor activation differently in androgen-dependent versus androgen-independent human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Moss, Patrice E.; Lyles, Besstina E.; Stewart, LaMonica V., E-mail: lstewart@mmc.edu

    2010-12-10

    The androgen receptor (AR) regulates growth and progression of androgen-dependent as well as androgen-independent prostate cancer cells. Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) agonists have been reported to reduce AR activation in androgen-dependent LNCaP prostate cancer cells. To determine whether PPAR{gamma} ligands are equally effective at inhibiting AR activity in androgen-independent prostate cancer, we examined the effect of the PPAR{gamma} ligands ciglitazone and rosiglitazone on C4-2 cells, an androgen- independent derivative of the LNCaP cell line. Luciferase-based reporter assays and Western blot analysis demonstrated that PPAR{gamma} ligand reduced dihydrotestosterone (DHT)-induced increases in AR activity in LNCaP cells. However, in C4-2 cells, these compounds increased DHT-induced AR driven luciferase activity. In addition, ciglitazone did not significantly alter DHT-mediated increases in prostate specific antigen (PSA) protein or mRNA levels within C4-2 cells. siRNA-based experiments demonstrated that the ciglitazone-induced regulation of AR activity observed in C4-2 cells was dependent on the presence of PPAR{gamma}. Furthermore, overexpression of the AR corepressor cyclin D1 inhibited the ability of ciglitazone to induce AR luciferase activity in C4-2 cells. Thus, our data suggest that both PPAR{gamma} and cyclin D1 levels influence the ability of ciglitazone to differentially regulate AR signaling in androgen-independent C4-2 prostate cancer cells.

  15. High abundance androgen receptor in goldfish brain: characteristics and seasonal changes

    International Nuclear Information System (INIS)

    Pasmanik, M.; Callard, G.V.

    1988-01-01

    Testosterone (T) exerts its actions in brain directly via androgen receptors or, after aromatization to estradiol, via estrogen receptors. Brain aromatase activity in teleost fish is 100-1000 times greater than in mammals and would be expected to significantly reduce the quantity of androgen available for receptor binding. Experiments were carried out on the goldfish Carassius auratus to determine if androgen receptors are present in teleost brain and whether their physicochemical properties reflect elevated aromatase. Cytosolic and nuclear extracts were assayed with the use of [ 3 H]T and charcoal, Sephadex LH-20, or DNA-cellulose chromatography to separate bound and free steroids. Binding activity was saturable and had an equally high affinity for T and 5 alpha-dihydrotestosterone. Although mibolerone was a relatively weak competitor, the putative teleost androgen 11-ketotestosterone, methyltrienolone (R1881), estradiol, progesterone, and cortisol were poor ligands. Characteristics that distinguish this receptor from a steroid-binding protein in goldfish serum are the presence of binding activity in both nuclear and cytosolic extracts, a low rate of ligand-receptor dissociation, electrophoretic mobility, sedimentation properties in low vs. high salt, and tissue distribution. DNA cellulose-adhering and nonadhering forms were detected, but these did not differ in other variables measured. Although goldfish androgen receptors resembled those of mammals in all important physicochemical characteristics, they were unusually abundant compared to levels in rat brain, but comparable to levels in prostate and other male sex hormone target organs. Moreover, there were seasonal variations in total receptors, with a peak at spawning (April) 4- to 5-fold higher than values in reproductively inactive fish

  16. Androgen receptor function links human sexual dimorphism to DNA methylation.

    Directory of Open Access Journals (Sweden)

    Ole Ammerpohl

    Full Text Available Sex differences are well known to be determinants of development, health and disease. Epigenetic mechanisms are also known to differ between men and women through X-inactivation in females. We hypothesized that epigenetic sex differences may also result from sex hormone functions, in particular from long-lasting androgen programming. We aimed at investigating whether inactivation of the androgen receptor, the key regulator of normal male sex development, is associated with differences of the patterns of DNA methylation marks in genital tissues. To this end, we performed large scale array-based analysis of gene methylation profiles on genomic DNA from labioscrotal skin fibroblasts of 8 males and 26 individuals with androgen insensitivity syndrome (AIS due to inactivating androgen receptor gene mutations. By this approach we identified differential methylation of 167 CpG loci representing 162 unique human genes. These were significantly enriched for androgen target genes and low CpG content promoter genes. Additional 75 genes showed a significant increase of heterogeneity of methylation in AIS compared to a high homogeneity in normal male controls. Our data show that normal and aberrant androgen receptor function is associated with distinct patterns of DNA-methylation marks in genital tissues. These findings support the concept that transcription factor binding to the DNA has an impact on the shape of the DNA methylome. These data which derived from a rare human model suggest that androgen programming of methylation marks contributes to sexual dimorphism in the human which might have considerable impact on the manifestation of sex-associated phenotypes and diseases.

  17. Zebrafish (Danio rerio) androgen receptor: sequence homology and up-regulation by the fungicide vinclozolin.

    Science.gov (United States)

    Smolinsky, Amanda N; Doughman, Jennifer M; Kratzke, Liên-Thành C; Lassiter, Christopher S

    2010-03-01

    Steroid hormones regulate gene expression in organisms by binding to receptor proteins. These hormones include the androgens, which signal through androgen receptors (ARs). Endocrine disrupters (EDCs) are chemicals in the environment that adversely affect organisms by binding to nuclear receptors, including ARs. Vinclozolin, a fungicide used on fruit and vegetable crops, is a known anti-androgen, a type of EDC that blocks signals from testosterone and its derivatives. In order to better understand the effects of EDCs, further research on androgen receptors and other hormone signaling pathways is necessary. In this study, we demonstrate the evolutionary conservation between the genomic structure of the human and zebrafish ar genes and find that ar mRNA expression increases in zebrafish embryos exposed to vinclozolin, which may be evolutionarily conserved as well. At 48 and 72 h post-fertilization, vinclozolin-treated embryos express ar mRNA 8-fold higher than the control level. These findings suggest that zebrafish embryos attempt to compensate for the presence of an anti-androgen by increasing the number of androgen receptors available.

  18. Hormonal control of spermatogenesis: expression of FSJH receptor and androgen receptor genes

    NARCIS (Netherlands)

    L.J. Blok (Leen)

    1992-01-01

    textabstractFSH and testosterone are the main hormonal regulators of spermatogenesis. The actions of androgens and FSH are mediated by their respective receptors. Receptor gene expression (mRNA and protein). is an important determinant of hormone action. Biochemical aspects of the regulation of

  19. Context dependent regulatory patterns of the androgen receptor and androgen receptor target genes

    International Nuclear Information System (INIS)

    Olsen, Jan Roger; Azeem, Waqas; Hellem, Margrete Reime; Marvyin, Kristo; Hua, Yaping; Qu, Yi; Li, Lisha; Lin, Biaoyang; Ke, XI- Song; Øyan, Anne Margrete; Kalland, Karl- Henning

    2016-01-01

    Expression of the androgen receptor (AR) is associated with androgen-dependent proliferation arrest and terminal differentiation of normal prostate epithelial cells. Additionally, activation of the AR is required for survival of benign luminal epithelial cells and primary cancer cells, thus androgen deprivation therapy (ADT) leads to apoptosis in both benign and cancerous tissue. Escape from ADT is known as castration-resistant prostate cancer (CRPC). In the course of CRPC development the AR typically switches from being a cell-intrinsic inhibitor of normal prostate epithelial cell proliferation to becoming an oncogene that is critical for prostate cancer cell proliferation. A clearer understanding of the context dependent activation of the AR and its target genes is therefore desirable. Immortalized human prostate basal epithelial EP156T cells and progeny cells that underwent epithelial to mesenchymal transition (EMT), primary prostate epithelial cells (PrECs) and prostate cancer cell lines LNCaP, VCaP and 22Rv1 were used to examine context dependent restriction and activation of the AR and classical target genes, such as KLK3. Genome-wide gene expression analyses and single cell protein analyses were applied to study the effect of different contexts. A variety of growth conditions were tested and found unable to activate AR expression and transcription of classical androgen-dependent AR target genes, such as KLK3, in prostate epithelial cells with basal cell features or in mesenchymal type prostate cells. The restriction of androgen- and AR-dependent transcription of classical target genes in prostate basal epithelial cells was at the level of AR expression. Exogenous AR expression was sufficient for androgen-dependent transcription of AR target genes in prostate basal epithelial cells, but did not exert a positive feedback on endogenous AR expression. Treatment of basal prostate epithelial cells with inhibitors of epigenetic gene silencing was not efficient in

  20. Androgen regulation of the androgen receptor coregulators

    International Nuclear Information System (INIS)

    Urbanucci, Alfonso; Waltering, Kati K; Suikki, Hanna E; Helenius, Merja A; Visakorpi, Tapio

    2008-01-01

    The critical role of the androgen receptor (AR) in the development of prostate cancer is well recognized. The transcriptional activity of AR is partly regulated by coregulatory proteins. It has been suggested that these coregulators could also be important in the progression of prostate cancer. The aim of this study was to identify coregulators whose expression is regulated by either the androgens and/or by the expression level of AR. We used empty vector and AR cDNA-transfected LNCaP cells (LNCaP-pcDNA3.1, and LNCaP-ARhi, respectively), and grew them for 4 and 24 hours in the presence of dihydrotestosterone (DHT) at various concentrations. The expression of 25 AR coregulators (SRC1, TIF2, PIAS1, PIASx, ARIP4, BRCA1, β-catenin, AIB3, AIB1, CBP, STAT1, NCoR1, AES, cyclin D1, p300, ARA24, LSD1, BAG1L, gelsolin, prohibitin, JMJD2C, JMJD1A, MAK, PAK6 and MAGE11) was then measured by using real-time quantitative RT-PCR (Q-RT-PCR). Five of the coregulators (AIB1, CBP, MAK, BRCA1 and β-catenin) showed more than 2-fold induction and 5 others (cyclin D1, gelsolin, prohibitin, JMJD1A, and JMJD2C) less than 2-fold induction. Overexpression of AR did not affect the expression of the coregulators alone. However, overexpression of AR enhanced the DHT-stimulated expression of MAK, BRCA1, AIB1 and CBP and reduced the level of expression of β-catenin, cyclinD1 and gelsolin. In conclusion, we identified 5 coactivators whose expression was induced by androgens suggesting that they could potentiate AR signaling. Overexpression of AR seems to sensitize cells for low levels of androgens

  1. Androgen receptor-related diseases: what do we know?

    Science.gov (United States)

    Shukla, G C; Plaga, A R; Shankar, E; Gupta, S

    2016-05-01

    The androgen receptor (AR) and the androgen-AR signaling pathway play a significant role in male sexual differentiation and the development and function of male reproductive and non-reproductive organs. Because of AR's widely varied and important roles, its abnormalities have been identified in various diseases such as androgen insensitivity syndrome, spinal bulbar muscular atrophy, benign prostatic hyperplasia, and prostate cancer. This review provides an overview of the function of androgens and androgen-AR mediated diseases. In addition, the diseases delineated above are discussed with respect to their association with mutations and other post-transcriptional modifications in the AR. Finally, we present an introduction to the potential therapeutic application of most recent pharmaceuticals including miRNAs in prostate cancer that specifically target the transactivation function of the AR at post-transcriptional stages. © 2016 American Society of Andrology and European Academy of Andrology.

  2. Enhanced Androgen Signaling With Androgen Receptor Overexpression in the Osteoblast Lineage Controls Skeletal Turnover, Matrix Quality and Bone Architecture

    National Research Council Canada - National Science Library

    Wiren, Kristine M; Jepsen, Karl

    2006-01-01

    .... We genetically engineered transgenic mice in which androgen receptor (AR) overexpression is skeletally targeted in two separate models to better understand the role of androgen signaling directly in bone...

  3. Targeting Prostate Cancer with Bifunctional Modulators of the Androgen Receptor

    Science.gov (United States)

    2015-06-01

    Wittmann, B.; Dwyer, M.; Cui, H.; Dye, D.; McDonnell, D.; Norris , J. Inhibition of prostate cancer cell growth by second-site androgen receptor antagonists...Wittmann, B.; Dwyer, M.; Cui, H.; Dye, D.; McDonnell, D.; Norris , J. Inhibition of prostate cancer cell growth by second-site androgen receptor...important clin- ical problem in diseases such as asthma (51, 52), ne- phrotic syndrome (53), and malignancies such as acute lymphoblastic leukemia (54

  4. Phosphorylation of histone H3 at threonine 11 establishes a novel chromatin mark for transcriptional regulation

    OpenAIRE

    Metzger, Eric; Yin, Na; Wissmann, Melanie; Kunowska, Natalia; Fischer, Kristin; Friedrichs, Nicolaus; Patnaik, Debasis; Higgins, Jonathan M.G.; Potier, Noelle; Scheidtmann, Karl-Heinz; Buettner, Reinhard; Schüle, Roland

    2007-01-01

    Posttranslational modifications of histones such as methylation, acetylation, and phosphorylation regulate chromatin structure and gene expression. Here we show that protein kinase C-related kinase 1 (PRK1) phosphorylates histone H3 at threonine 11 (H3T11) upon ligand-dependent recruitment to androgen receptor (AR) target genes. PRK1 is pivotal to AR function since PRK1 knockdown or inhibition impedes AR-dependent transcription. Blocking PRK1 function abrogates androgen-induced H3T11 phosphor...

  5. Therapeutic potential of the SARMs: revisiting the androgen receptor for drug discovery.

    Science.gov (United States)

    Segal, Scott; Narayanan, Ramesh; Dalton, James T

    2006-04-01

    Selective androgen receptor modulators (SARMS) bind to the androgen receptor and demonstrate anabolic activity in a variety of tissues; however, unlike testosterone and other anabolic steroids, these nonsteroidal agents are able to induce bone and muscle growth, as well as shrinking the prostate. The potential of SARMS is to maximise the positive attributes of steroidal androgens as well as minimising negative effects, thus providing therapeutic opportunities in a variety of diseases, including muscle wasting associated with burns, cancer, end-stage renal disease, osteoporosis, frailty and hypogonadism. This review summarises androgen physiology, the current status of the R&D of SARMS and potential therapeutic indications for this emerging class of drugs.

  6. Gβ promotes pheromone receptor polarization and yeast chemotropism by inhibiting receptor phosphorylation.

    Science.gov (United States)

    Ismael, Amber; Tian, Wei; Waszczak, Nicholas; Wang, Xin; Cao, Youfang; Suchkov, Dmitry; Bar, Eli; Metodiev, Metodi V; Liang, Jie; Arkowitz, Robert A; Stone, David E

    2016-04-12

    Gradient-directed cell migration (chemotaxis) and growth (chemotropism) are processes that are essential to the development and life cycles of all species. Cells use surface receptors to sense the shallow chemical gradients that elicit chemotaxis and chemotropism. Slight asymmetries in receptor activation are amplified by downstream signaling systems, which ultimately induce dynamic reorganization of the cytoskeleton. During the mating response of budding yeast, a model chemotropic system, the pheromone receptors on the plasma membrane polarize to the side of the cell closest to the stimulus. Although receptor polarization occurs before and independently of actin cable-dependent delivery of vesicles to the plasma membrane (directed secretion), it requires receptor internalization. Phosphorylation of pheromone receptors by yeast casein kinase 1 or 2 (Yck1/2) stimulates their internalization. We showed that the pheromone-responsive Gβγ dimer promotes the polarization of the pheromone receptor by interacting with Yck1/2 and locally inhibiting receptor phosphorylation. We also found that receptor phosphorylation is essential for chemotropism, independently of its role in inducing receptor internalization. A mathematical model supports the idea that the interaction between Gβγ and Yck1/2 results in differential phosphorylation and internalization of the pheromone receptor and accounts for its polarization before the initiation of directed secretion. Copyright © 2016, American Association for the Advancement of Science.

  7. Expression, purification and crystallization of the ancestral androgen receptor-DHT complex.

    Science.gov (United States)

    Colucci, Jennifer K; Ortlund, Eric A

    2013-09-01

    Steroid receptors (SRs) are a closely related family of ligand-dependent nuclear receptors that mediate the transcription of genes critical for development, reproduction and immunity. SR dysregulation has been implicated in cancer, inflammatory diseases and metabolic disorders. SRs bind their cognate hormone ligand with exquisite specificity, offering a unique system to study the evolution of molecular recognition. The SR family evolved from an estrogen-sensitive ancestor and diverged to become sensitive to progestagens, corticoids and, most recently, androgens. To understand the structural mechanisms driving the evolution of androgen responsiveness, the ancestral androgen receptor (ancAR1) was crystallized in complex with 5α-dihydrotestosterone (DHT) and a fragment of the transcriptional mediator/intermediary factor 2 (Tif2). Crystals diffracted to 2.1 Å resolution and the resulting structure will permit a direct comparison with its progestagen-sensitive ancestor, ancestral steroid receptor 2 (AncSR2).

  8. Androgen receptor activity modulates responses to cisplatin treatment in bladder cancer.

    Science.gov (United States)

    Kashiwagi, Eiji; Ide, Hiroki; Inoue, Satoshi; Kawahara, Takashi; Zheng, Yichun; Reis, Leonardo O; Baras, Alexander S; Miyamoto, Hiroshi

    2016-08-02

    Cisplatin (CDDP)-based combination chemotherapy remains the mainstream treatment for advanced bladder cancer. However, its efficacy is often limited due to the development of resistance for which underlying mechanisms are poorly understood. Meanwhile, emerging evidence has indicated the involvement of androgen-mediated androgen receptor (AR) signals in bladder cancer progression. In this study, we aimed to investigate whether AR signals have an impact on sensitivity to CDDP in bladder cancer cells. UMUC3-control-short hairpin RNA (shRNA) cells with endogenous AR and AR-negative 647V/5637 cells stably expressing AR were significantly more resistant to CDDP treatment at its pharmacological concentrations, compared with UMUC3-AR-shRNA and 647V-vector/5637-vector control cells, respectively. A synthetic androgen R1881 significantly reduced CDDP sensitivity in UMUC3, 647V-AR, or 5637-AR cells, and the addition of an anti-androgen hydroxyflutamide inhibited the effect of R1881. In these AR-positive cells, R1881 treatment also induced the expression levels of NF-κB, which is known to involve CDDP resistance, and its phosphorylated form, as well as nuclear translocation of NF-κB. In CDDP-resistant bladder cancer sublines established following long-term culture with CDDP, the expression levels of AR as well as NF-κB and phospho-NF-κB were considerably elevated, compared with respective control sublines. In bladder cancer specimens, there was a strong trend to correlate between AR positivity and chemoresistance. These results suggest that AR activation correlates with CDDP resistance presumably via modulating NF-κB activity in bladder cancer cells. Targeting AR during chemotherapy may thus be a useful strategy to overcome CDDP resistance in patients with AR-positive bladder cancer.

  9. Luteinizing hormone-induced Akt phosphorylation and androgen production are modulated by MAP Kinase in bovine theca cells

    Directory of Open Access Journals (Sweden)

    Fukuda Shin

    2009-11-01

    Full Text Available Abstract Background Theca cells play an important role in controlling ovarian steroidogenesis by providing aromatizable androgens for granulosa cell estrogen biosynthesis. Although it is well established that the steroidogenic activity of theca cells is mainly regulated by LH, the intracellular signal transduction mechanisms that regulate thecal proliferation and/or steroidogenesis remain obscure. In this study, we examined whether and how LH controls the PI3K/Akt signaling pathway and androgen production in bovine theca cells. We also explored whether this LH-induced PI3K/Akt activation is modulated with other signaling pathways (i.e. PKA and MAPK. Methods Ovarian theca cells were isolated from bovine small antral follicles and were incubated with LH for various durations. Phospho-Akt and total-Akt content in the cultured theca cells were examined using Western blotting. Androstenedione levels in the spent media were determined using EIA. Semi-quantitative RT-PCR analyses were conducted to analyze the mRNA levels of CYP17A1 and StAR in the theca cells. To examine whether Akt activity is involved in theca cell androgen production, the PI3K inhibitors wortmannin and LY294002 were also added to the cells. Results Akt is constitutively expressed, but is gradually phosphorylated in cultured bovine theca cells through exposure to LH. LH significantly increased androstenedione production in bovine theca cells, whereas addition of the wortmannin and LY294002 significantly decreased LH-induced androstenedione production. LH significantly increased CYP17A1 mRNA level in theca cells, whereas addition of LY294002 significantly decreased LH-induced CYP17A1 expression. Neither LH nor PI3K inhibitors alter the mRNA levels of StAR in theca cells. Although H89 (a selective inhibitor of PKA does not affect LH-mediated changes in Akt, U0126 (a potent MEK inhibitor suppressed LH-induced Akt phosphorylation, CYP17A1 expression, and androgen production in theca

  10. Structural characteristics of anabolic androgenic steroids contributing to binding to the androgen receptor and to their anabolic and androgenic activities. Applied modifications in the steroidal structure.

    Science.gov (United States)

    Fragkaki, A G; Angelis, Y S; Koupparis, M; Tsantili-Kakoulidou, A; Kokotos, G; Georgakopoulos, C

    2009-02-01

    Anabolic androgenic steroids (AAS) are synthetic derivatives of testosterone introduced for therapeutic purposes providing enhanced anabolic potency with reduced androgenic effects. Androgens mediate their action through their binding to the androgen receptor (AR) which is mainly expressed in androgen target tissues, such as the prostate, skeletal muscle, liver and central nervous system. This paper reviews some of the wide spectrum of testosterone and synthetic AAS structure modifications related to the intended enhancement in anabolic activity. The structural features of steroids necessary for effective binding to the AR and those which contribute to the stipulation of the androgenic and anabolic activities are also presented.

  11. Antiandrogens act as selective androgen receptor modulators at the proteome level in prostate cancer cells.

    Science.gov (United States)

    Brooke, Greg N; Gamble, Simon C; Hough, Michael A; Begum, Shajna; Dart, D Alwyn; Odontiadis, Michael; Powell, Sue M; Fioretti, Flavia M; Bryan, Rosie A; Waxman, Jonathan; Wait, Robin; Bevan, Charlotte L

    2015-05-01

    Current therapies for prostate cancer include antiandrogens, inhibitory ligands of the androgen receptor, which repress androgen-stimulated growth. These include the selective androgen receptor modulators cyproterone acetate and hydroxyflutamide and the complete antagonist bicalutamide. Their activity is partly dictated by the presence of androgen receptor mutations, which are commonly detected in patients who relapse while receiving antiandrogens, i.e. in castrate-resistant prostate cancer. To characterize the early proteomic response to these antiandrogens we used the LNCaP prostate cancer cell line, which harbors the androgen receptor mutation most commonly detected in castrate-resistant tumors (T877A), analyzing alterations in the proteome, and comparing these to the effect of these therapeutics upon androgen receptor activity and cell proliferation. The majority are regulated post-transcriptionally, possibly via nongenomic androgen receptor signaling. Differences detected between the exposure groups demonstrate subtle changes in the biological response to each specific ligand, suggesting a spectrum of agonistic and antagonistic effects dependent on the ligand used. Analysis of the crystal structures of the AR in the presence of cyproterone acetate, hydroxyflutamide, and DHT identified important differences in the orientation of key residues located in the AF-2 and BF-3 protein interaction surfaces. This further implies that although there is commonality in the growth responses between androgens and those antiandrogens that stimulate growth in the presence of a mutation, there may also be influential differences in the growth pathways stimulated by the different ligands. This therefore has implications for prostate cancer treatment because tumors may respond differently dependent upon which mutation is present and which ligand is activating growth, also for the design of selective androgen receptor modulators, which aim to elicit differential proteomic

  12. Androgen receptor disruption increases the osteogenic response to mechanical loading in male mice

    NARCIS (Netherlands)

    Callewaert, F.; Bakker, A.; Schrooten, J.; Van Meerbeek, B.; Verhoeven, G.; Boonen, S.; Vanderschueren, D.

    2010-01-01

    In female mice, estrogen receptor-alpha (ERα) mediates the anabolic response of bone to mechanical loading. Whether ERα plays a similar role in the male skeleton and to what extent androgens and androgen receptor (AR) affect this response in males remain unaddressed. Therefore, we studied the

  13. An unusual protein kinase phosphorylates the chemotactic receptor of Dictystelium discoideum

    International Nuclear Information System (INIS)

    Meier, K.; Klein, C.

    1988-01-01

    The authors report the cAMP-dependent phosphorylation of the chemotactic receptor of Dictyostelium discoideum in partially purified plasma membranes. The protein kinase responsible for receptor phosphorylation is associated with this fraction and preferentially phosphorylates the ligand-occupied form of the receptor. 8-Azido[ 32 P]cAMP labeling of the cell surface has shown that the cAMP receptor exists in two forms. A 45-kDa protein is predominant on unstimulated cells. cAMP stimulation results in an increased receptor phosphorylation such that the receptor migrates on NaDodSO 4 /PAGE as a 47-kDa protein. Phosphorylation of the chemotactic receptor is not detected in membrane preparations unless cAMP is added to the incubation mixture. Only under those conditions is the phosphorylated 47-kDa form observed. The requirement for cAMP reflects the fact that the kinase involved preferentially uses the ligand-occupied receptor as a substrate. In vitro phosphorylation of the receptor does not involve tyrosine residues. The enzyme does not appear to be a cAMP- or cGMP-dependent protein kinase nor is it sensitive to guanine nucleotides, Ca 2+ /calmodulin, Ca 2+ /phospholipid, or EGTA. Similarities with the β-adrenergic receptor protein kinase are discussed

  14. The long-term outcome of boys with partial androgen insensitivity syndrome and a mutation in the androgen receptor gene

    NARCIS (Netherlands)

    Lucas-Herald, A.; S. Bertelloni (Silvano); A. Juul (Anders); J. Bryce (Jillian); Jiang, J.; M. Rodie (Martina); R. Sinnott (Richard); Boroujerdi, M.; Lindhardt Johansen, M.; O. Hiort (Olaf); P-M. Holterhus (Paul-Martin); M.L. Cools (Martine); Guaragna-Filho, G.; Guerra-Junior, G.; N. Weintrob (Naomi); S.E. Hannema (Sabine); S.L.S. Drop (Stenvert); T. Guran (Tulay); F. Darendeliler (Feyza); A. Nordenström (Anna); I.A. Hughes (Ieuan A.); Acerini, C.; Tadokoro-Cuccaro, R.; S.F. Ahmed (Faisal)

    2016-01-01

    textabstractBackground: In boys with suspected partial androgen insensitivity syndrome (PAIS), systematic evidence that supports the long-term prognostic value of identifying a mutation in the androgen receptor gene (AR) is lacking. Objective: To assess the clinical characteristics and long-term

  15. Phenobarbital Meets Phosphorylation of Nuclear Receptors.

    Science.gov (United States)

    Negishi, Masahiko

    2017-05-01

    Phenobarbital was the first therapeutic drug to be characterized for its induction of hepatic drug metabolism. Essentially at the same time, cytochrome P450, an enzyme that metabolizes drugs, was discovered. After nearly 50 years of investigation, the molecular target of phenobarbital induction has now been delineated to phosphorylation at threonine 38 of the constitutive androstane receptor (NR1I3), a member of the nuclear receptor superfamily. Determining this mechanism has provided us with the molecular basis to understand drug induction of drug metabolism and disposition. Threonine 38 is conserved as a phosphorylation motif in the majority of both mouse and human nuclear receptors, providing us with an opportunity to integrate diverse functions of nuclear receptors. Here, I review the works and accomplishments of my laboratory at the National Institutes of Health National Institute of Environmental Health Sciences and the future research directions of where our study of the constitutive androstane receptor might take us. U.S. Government work not protected by U.S. copyright.

  16. The Role of (BETA)-Catenin in Androgen Receptor Signaling

    National Research Council Canada - National Science Library

    Bhowmick, Neil A

    2006-01-01

    .... Our preliminary data seem indicate stromally derived paracrine Wnt family members activate theepithelial frizzled receptor to enable prostate epithelial survival in an androgen deficient environment...

  17. Androgen receptor and immune inflammation in benign prostatic hyperplasia and prostate cancer

    Science.gov (United States)

    Izumi, Kouji; Li, Lei; Chang, Chawnshang

    2014-01-01

    Both benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are frequent diseases in middle-aged to elderly men worldwide. While both diseases are linked to abnormal growth of the prostate, the epidemiological and pathological features of these two prostate diseases are different. BPH nodules typically arise from the transitional zone, and, in contrast, PCa arises from the peripheral zone. Androgen deprivation therapy alone may not be sufficient to cure these two prostatic diseases due to its undesirable side effects. The alteration of androgen receptor-mediated inflammatory signals from infiltrating immune cells and prostate stromal/epithelial cells may play key roles in those unwanted events. Herein, this review will focus on the roles of androgen/androgen receptor signals in the inflammation-induced progression of BPH and PCa. PMID:26594314

  18. Sexual behavior reduces hypothalamic androgen receptor immunoreactivity

    NARCIS (Netherlands)

    Fernandez-Guasti, Alonso; Swaab, Dick; Rodríguez-Manzo, Gabriela

    2003-01-01

    Male sexual behavior is regulated by limbic areas like the medial preoptic nucleus (MPN), the bed nucleus of the stria terminalis (BST), the nucleus accumbens (nAcc) and the ventromedial hypothalamic nucleus (VMN). Neurons in these brain areas are rich in androgen receptors (AR) and express

  19. Expression of a hyperactive androgen receptor leads to androgen-independent growth of prostate cancer cells.

    Science.gov (United States)

    Hsieh, Chen-Lin; Cai, Changmeng; Giwa, Ahmed; Bivins, Aaronica; Chen, Shao-Yong; Sabry, Dina; Govardhan, Kumara; Shemshedini, Lirim

    2008-07-01

    Cellular changes that affect the androgen receptor (AR) can cause prostate cancer to transition from androgen dependent to androgen independent, which is usually lethal. One common change in prostate tumors is overexpression of the AR, which has been shown to lead to androgen-independent growth of prostate cancer cells. This led us to hypothesize that expression of a hyperactive AR would be sufficient for androgen-independent growth of prostate cancer cells. To test this hypothesis, stable lune cancer prostate (LNCaP) cell lines were generated, which express a virion phosphoprotein (VP)16-AR hybrid protein that contains full-length AR fused to the strong viral transcriptional activation domain VP16. This fusion protein elicited as much as a 20-fold stronger transcriptional activity than the natural AR. Stable expression of VP16-AR in LNCaP cells yielded androgen-independent cell proliferation, while under the same growth conditions the parental LNCaP cells exhibited only androgen-dependent growth. These results show that expression of a hyperactive AR is sufficient for androgen-independent growth of prostate cancer cells. To study the molecular basis of this enhanced growth, we measured the expression of soluble guanylyl cyclase-alpha1 (sGCalpha1), a subunit of the sGC, an androgen-regulated gene that has been shown to be involved in prostate cancer cell growth. Interestingly, the expression of sGCalpha1 is androgen independent in VP16-AR-expressing cells, in contrast to its androgen-induced expression in control LNCaP cells. RNA(I)-dependent inhibition of sGCalpha1 expression resulted in significantly reduced proliferation of VP16-AR cells, implicating an important role for sGCalpha1 in the androgen-independent growth of these cells.

  20. Synthetic anabolic agents: steroids and nonsteroidal selective androgen receptor modulators.

    Science.gov (United States)

    Thevis, Mario; Schänzer, Wilhelm

    2010-01-01

    The central role of testosterone in the development of male characteristics, as well as its beneficial effects on physical performance and muscle growth, has led to the search for synthetic alternatives with improved pharmacological profiles. Hundreds of steroidal analogs have been prepared with a superior oral bioavailability, which should also possess reduced undesirable effects. However, only a few entered the pharmaceutical market due to severe toxicological incidences that were mainly attributed to the lack of tissue selectivity. Prominent representatives of anabolic-androgenic steroids (AAS) are for instance methyltestosterone, metandienone and stanozolol, which are discussed as model compounds with regard to general pharmacological aspects of synthetic AAS. Recently, nonsteroidal alternatives to AAS have been developed that selectively activate the androgen receptor in either muscle tissue or bones. These so-called selective androgen receptor modulators (SARMs) are currently undergoing late clinical trials (IIb) and will be prohibited by the World Anti-Doping Agency from January 2008. Their entirely synthetic structures are barely related to steroids, but particular functional groups allow for the tissue-selective activation or inhibition of androgen receptors and, thus, the stimulation of muscle growth without the risk of severe undesirable effects commonly observed in steroid replacement therapies. Hence, these compounds possess a high potential for misuse in sports and will be the subject of future doping control assays.

  1. Androgen receptor status is a prognostic marker in non-basal triple negative breast cancers and determines novel therapeutic options.

    Directory of Open Access Journals (Sweden)

    Pierluigi Gasparini

    Full Text Available Triple negative breast cancers are a heterogeneous group of tumors characterized by poor patient survival and lack of targeted therapeutics. Androgen receptor has been associated with triple negative breast cancer pathogenesis, but its role in the different subtypes has not been clearly defined. We examined androgen receptor protein expression by immunohistochemical analysis in 678 breast cancers, including 396 triple negative cancers. Fifty matched lymph node metastases were also examined. Association of expression status with clinical (race, survival and pathological (basal, non-basal subtype, stage, grade features was also evaluated. In 160 triple negative breast cancers, mRNA microarray expression profiling was performed, and differences according to androgen receptor status were analyzed. In triple negative cancers the percentage of androgen receptor positive cases was lower (24.8% vs 81.6% of non-triple negative cases, especially in African American women (16.7% vs 25.5% of cancers of white women. No significant difference in androgen receptor expression was observed in primary tumors vs matched metastatic lesions. Positive androgen receptor immunoreactivity was inversely correlated with tumor grade (p<0.01 and associated with better overall patient survival (p = 0.032 in the non-basal triple negative cancer group. In the microarray study, expression of three genes (HER4, TNFSF10, CDK6 showed significant deregulation in association with androgen receptor status; eg CDK6, a novel therapeutic target in triple negative cancers, showed significantly higher expression level in androgen receptor negative cases (p<0.01. These findings confirm the prognostic impact of androgen receptor expression in non-basal triple negative breast cancers, and suggest targeting of new androgen receptor-related molecular pathways in patients with these cancers.

  2. 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 ...

  3. Cloning of the human androgen receptor cDNA

    International Nuclear Information System (INIS)

    Govindan, M.V.; Burelle, M.; Cantin, C.; Kabrie, C.; Labrie, F.; Lachance, Y.; Leblanc, G.; Lefebvre, C.; Patel, P.; Simard, J.

    1988-01-01

    The authors discuss how in order to define the functional domains of the human androgen receptor, complementary DNA (cDNA) clones encoding the human androgen receptor (hAR) have been isolated from a human testis λgtll cDNA library using synthetic oligonnucleotide probes, homologous to segments of the human glucocorticoid, estradiol and progesterone receptors. The cDNA clones corresponding to the human glucocorticoid, estradiol and progesterone receptors were eliminated after cross-hybridization with their respective cDNA probes and/or after restriction mapping of the cDNA clones. The remaining cDNA clones were classified into different groups after analysis by restriction digestion and cross-hybridization. Two of the largest cDNA clones from each group were inserted into an expression vector in both orientations. The linearized plasmids were used as templates in in vitro transcription with T7 RNA polymerase. Subsequent in vitro translation of the purified transcripts in rabbit reticulocyte lysate followed by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) permitted the characterization of the encoded polyeptides. The expressed proteins larger than 30,000 Da were analyzed for their ability to bind tritium-labelled dihydrotestosterone ([ 3 H] DHT) with high affinity and specificity

  4. Androgen receptors in the pelvic diaphragm muscles of dogs with and without perineal hernia.

    Science.gov (United States)

    Mann, F A; Nonneman, D J; Pope, E R; Boothe, H W; Welshons, W V; Ganjam, V K

    1995-01-01

    Levator ani and coccygeus muscle estrogen and androgen receptors were measured in 6, healthy, > or = 5-year-old, noncastrated, male Beagles (controls) and in 24 dogs with perineal hernia. Estrogen and androgen receptor analyses were performed on levator ani and coccygeus muscle specimens obtained from control dogs at the time of castration; contralateral levator ani and coccygeus muscle specimens were assayed 2 months after castration. During herniorrhaphy of dogs with perineal hernia, levator ani (non-castrated, n = 12; castrated, n = 7) and/or coccygeus (noncastrated, n = 5; castrated, n = 4) muscle biopsy specimens were obtained for estrogen and androgen receptor analyses. For estrogen and androgen receptor assays, each muscle biopsy specimen was homogenized in Tris-EDTA-glycerol buffer, and centrifuged at 30,000 x g; extracts were used for binding with ligands: [3H]methyltrienolone (3HR1881) for androgen receptors, and [3H]estradiol-17 beta for estrogen receptors. Extracts were incubated overnight at 0 to 4 C. Nonspecific binding was estimated, using 100-fold concentration of cold ligands. Bound and free hormones were separated, using hydroxylapatite batch assay. Receptor numbers for each tissue were calculated as femtomoles (fmol) per milligram of protein. Quantified data were compared between precastration and postcastration controls, using a paired t-test. One-way ANOVA and Bonferroni post-hoc test were used to compare values for precastration controls, postcastration controls, castrated dogs with perineal hernia, and noncastrated dogs with perineal hernia. Significance was set at P < 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Continuing Development of Alternative High-Throughput Screens to Determine Endocrine Disruption, Focusing on Androgen Receptor, Steroidogenesis, and Thyroid Pathways

    Science.gov (United States)

    The focus of this meeting is the SAP's review and comment on the Agency's proposed high-throughput computational model of androgen receptor pathway activity as an alternative to the current Tier 1 androgen receptor assay (OCSPP 890.1150: Androgen Receptor Binding Rat Prostate Cyt...

  6. Fenofibrate down-regulates the expressions of androgen receptor (AR) and AR target genes and induces oxidative stress in the prostate cancer cell line LNCaP

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hu; Zhu, Chen; Qin, Chao [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Tao, Tao [Department of Neurosurgery, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Li, Jie; Cheng, Gong; Li, Pu; Cao, Qiang; Meng, Xiaoxin; Ju, Xiaobing; Shao, Pengfei; Hua, Lixin [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Gu, Min, E-mail: medzhao1980@163.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Yin, Changjun, E-mail: drcjyin@gmail.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China)

    2013-03-08

    Highlights: ► Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells. ► Fenofibrate reduces the expressions of androgen receptor in LNCaP cells. ► Fenofibrate induces oxidative stress in the prostate cancer cell line LNCaP. -- Abstract: Fenofibrate, a peroxisome proliferator-androgen receptor-alpha agonist, is widely used in treating different forms of hyperlipidemia and hypercholesterolemia. Recent reports have indicated that fenofibrate exerts anti-proliferative and pro-apoptotic properties. This study aims to investigate the effects of fenofibrate on the prostate cancer (PCa) cell line LNCaP. The effects of fenofibrate on LNCaP cells were evaluated by flow cytometry, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assays, Western blot analysis, and dual-luciferase reporter assay. Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells, reduces the expressions of androgen receptor (AR) and AR target genes (prostate-specific antigen and TMPRSS2), and inhibits Akt phosphorylation. Fenofibrate can induce the accumulation of intracellular reactive oxygen species and malondialdehyde, and decrease the activities of total anti-oxidant and superoxide dismutase in LNCaP cells. Fenofibrate exerts an anti-proliferative property by inhibiting the expression of AR and induces apoptosis by causing oxidative stress. Therefore, our data suggest fenofibrate may have beneficial effects in fenofibrate users by preventing prostate cancer growth through inhibition of androgen activation and expression.

  7. Selective androgen receptor modulators in preclinical and clinical development.

    Science.gov (United States)

    Narayanan, Ramesh; Mohler, Michael L; Bohl, Casey E; Miller, Duane D; Dalton, James T

    2008-01-01

    Androgen receptor (AR) plays a critical role in the function of several organs including primary and accessory sexual organs, skeletal muscle, and bone, making it a desirable therapeutic target. Selective androgen receptor modulators (SARMs) bind to the AR and demonstrate osteo- and myo-anabolic activity; however, unlike testosterone and other anabolic steroids, these nonsteroidal agents produce less of a growth effect on prostate and other secondary sexual organs. SARMs provide therapeutic opportunities in a variety of diseases, including muscle wasting associated with burns, cancer, or end-stage renal disease, osteoporosis, frailty, and hypogonadism. This review summarizes the current standing of research and development of SARMs, crystallography of AR with SARMs, plausible mechanisms for their action and the potential therapeutic indications for this emerging class of drugs.

  8. Selectivity in progesterone and androgen receptor binding of progestagens used in oral contraceptives

    International Nuclear Information System (INIS)

    Kloosterboer, H.J.; Vonk-Noordegraaf, C.A.; Turpijn, E.W.

    1988-01-01

    The relative binding affinities (RBAs) of four progestational compounds (norethisterone, levonorgestrel, 3-keto-desogestrel and gestodene) for the human progesterone and androgen receptors were measured in MCF-7 cytosol and intact MCF-7 cells. For the binding to the progesterone receptor, both Org 2058 and Org 3236 (or 3-keto-desogestrel) were used as labelled ligands. The following ranking (low to high) for the RBA of the nuclear (intact cells) progesterone receptor irrespective of the ligand used is found: norethisterone much less than levonorgestrel less than 3-keto-destogestrel less than gestodene. The difference between the various progestagens is significant with the exception of that between 3-keto-desogestrel and gestodene, when Org 2058 is used as ligand. For the cytosolic progesterone receptor, the same order is found with the exception that similar RBAs are found for gestodene and 3-keto-desogestrel. The four progestagens clearly differ with respect to binding to the androgen receptor using dihydrotestosterone as labelled ligand in intact cells; the ranking (low to high) is: norethisterone less than 3 keto-desogestrel less than levonorgestrel and gestodene. The difference between 3-keto-desogestrel and levonorgestrel or gestodene is significant. The selectivity indices (ratio of the mean RBA for the progesterone receptor to that of androgen receptor) in intact cells are significantly higher for 3-keto-desogestrel and gestodene than for levonorgestrel and norethisterone. From these results we conclude that the introduction of the 18-methyl in norethisterone (levonorgestel) increases both the binding to the progesterone and androgen receptors

  9. Comparison of steroid receptors from the androgen responsive DDT1 cell line and the nonresponsive HVP cell line.

    Science.gov (United States)

    Norris, J S; Kohler, P O

    1978-01-01

    Two hamster cell lines have been isolated from androgen target tissue. The DDT1 cells derived from ductus deferens tissue exhibit a growth response to androgens, while the HVP cells derived from ventral prostate are androgen unresponsive. Both cell lines contain androgen receptors, that are similar when compared by kinetic methods, sedimentation velocity, chromatographic procedures or nuclear translocation ability. The forms of the high salt extracted nuclear receptors are indistinguishable chromatographically. Therefore, we postulate that the lesion preventing androgen induced growth in the HVP cell line is subseqent to nuclear translocation of the steroid receptor complex.

  10. Role of Androgen Receptor Variants in Prostate Cancer: Report from the 2017 Mission Androgen Receptor Variants Meeting.

    Science.gov (United States)

    Luo, Jun; Attard, Gerhardt; Balk, Steven P; Bevan, Charlotte; Burnstein, Kerry; Cato, Laura; Cherkasov, Artem; De Bono, Johann S; Dong, Yan; Gao, Allen C; Gleave, Martin; Heemers, Hannelore; Kanayama, Mayuko; Kittler, Ralf; Lang, Joshua M; Lee, Richard J; Logothetis, Christopher J; Matusik, Robert; Plymate, Stephen; Sawyers, Charles L; Selth, Luke A; Soule, Howard; Tilley, Wayne; Weigel, Nancy L; Zoubeidi, Amina; Dehm, Scott M; Raj, Ganesh V

    2018-05-01

    Although a number of studies have demonstrated the importance of constitutively active androgen receptor variants (AR-Vs) in prostate cancer, questions still remain about the precise role of AR-Vs in the progression of castration-resistant prostate cancer (CRPC). Key stakeholders and opinion leaders in prostate cancer convened on May 11, 2017 in Boston to establish the current state of the field of AR-Vs. The meeting "Mission Androgen Receptor Variants" was the second of its kind sponsored by the Prostate Cancer Foundation (PCF). This invitation-only event was attended by international leaders in the field and representatives from sponsoring organizations (PCF and industry sponsors). Eighteen faculty members gave short presentations, which were followed by in-depth discussions. Discussions focused on three thematic topics: (1) potential of AR-Vs as biomarkers of therapeutic resistance; (2) role of AR-Vs as functionally active CRPC progression drivers; and (3) utility of AR-Vs as therapeutic targets in CRPC. The three meeting organizers synthesized this meeting report, which is intended to summarize major data discussed at the meeting and identify key questions as well as strategies for addressing these questions. There was a critical consensus that further study of the AR-Vs is an important research focus in CRPC. Contrasting views and emphasis, each supported by data, were presented at the meeting, discussed among the participants, and synthesized in this report. This article highlights the state of knowledge and outlines the most pressing questions that need to be addressed to advance the AR-V field. Although further investigation is needed to delineate the role of androgen receptor (AR) variants in metastatic castration-resistant prostate cancer, advances in measurement science have enabled development of blood-based tests for treatment selection. Detection of AR variants (eg, AR-V7) identified a patient population with poor outcomes to existing AR

  11. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet.

    Science.gov (United States)

    Van Wagoner, Ryan M; Eichner, Amy; Bhasin, Shalender; Deuster, Patricia A; Eichner, Daniel

    2017-11-28

    Recent reports have described the increasing use of nonsteroidal selective androgen receptor modulators, which have not been approved by the US Food and Drug Administration (FDA), to enhance appearance and performance. The composition and purity of such products is not known. To determine the chemical identity and the amounts of ingredients in dietary supplements and products marketed and sold through the internet as selective androgen receptor modulators and compare the analyzed contents with product labels. Web-based searches were performed from February 18, 2016, to March 25, 2016, using the Google search engine on the Chrome and Internet Explorer web browsers to identify suppliers selling selective androgen receptor modulators. The products were purchased and the identities of the compounds and their amounts were determined from April to August 2016 using chain-of-custody and World Anti-Doping Association-approved analytical procedures. Analytical findings were compared against the label information. Products marketed and sold as selective androgen receptor modulators. Chemical identities and the amount of ingredients in each product marketed and sold as selective androgen receptor modulators. Among 44 products marketed and sold as selective androgen receptor modulators, only 23 (52%) contained 1 or more selective androgen receptor modulators (Ostarine, LGD-4033, or Andarine). An additional 17 products (39%) contained another unapproved drug, including the growth hormone secretagogue ibutamoren, the peroxisome proliferator-activated receptor-δ agonist GW501516, and the Rev-ErbA agonist SR9009. Of the 44 tested products, no active compound was detected in 4 (9%) and substances not listed on the label were contained in 11 (25%). In only 18 of the 44 products (41%), the amount of active compound in the product matched that listed on the label. The amount of the compounds listed on the label differed substantially from that found by analysis in 26 of 44 products

  12. Contributions of sex, testosterone, and androgen receptor CAG repeat number to virtual Morris water maze performance.

    Science.gov (United States)

    Nowak, Nicole T; Diamond, Michael P; Land, Susan J; Moffat, Scott D

    2014-03-01

    The possibility that androgens contribute to the male advantage typically found on measures of spatial cognition has been investigated using a variety of approaches. To date, evidence to support the notion that androgens affect spatial cognition in healthy young adults is somewhat equivocal. The present study sought to clarify the association between testosterone (T) and spatial performance by extending measurements of androgenicity to include both measures of circulating T as well as an androgen receptor-specific genetic marker. The aims of this study were to assess the contributions of sex, T, and androgen receptor CAG repeat number (CAGr) on virtual Morris water task (vMWT) performance in a group of healthy young men and women. The hypothesis that men would outperform women on vMWT outcomes was supported. Results indicate that CAGr may interact with T to impact navigation performance and suggest that consideration of androgen receptor sensitivity is an important consideration in evaluating hormone-behavior relationships. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Resveratrol, piceatannol and analogs inhibit activation of both wild-type and T877A mutant androgen receptor.

    Science.gov (United States)

    Lundqvist, Johan; Tringali, Corrado; Oskarsson, Agneta

    2017-11-01

    Prostate cancer growth and progression are mainly dependent on androgens and many current prostate cancer treatment options target the synthesis or function of androgens. We have previously reported that resveratrol and synthetic analogs of resveratrol with a higher bioavailability inhibit the synthesis of androgens in human adrenocortical H295R cells. Now we have studied the antiandrogenic properties of resveratrol, piceatannol and analogs in two different prostate cell lines; LNCaP and RWPE. LNCaP carry a T877A mutation in the androgen receptor while RWPE has a wild-type androgen receptor. We found that resveratrol, piceatannol and all studied analogs were able to inhibit a dihydrotestosterone-induced activation of the androgen receptor, showing that they act as antiandrogens. In LNCaP cells, all studied compounds were able to statistically significantly decrease the androgenic signaling in concentrations ≥1μM and the synthetic analogs trimethylresveratrol (RSVTM) and tetramethylpiceatannol (PICTM) were the most potent compounds. RWPE cells were not as responsive to the studied compounds as the LNCaP cells. A statistically significant decrease in the androgenic signaling was observed at concentrations ≤5μM for most compounds and RSVTM was found to be the most potent compound. Further, we studied the effects of resveratrol, piceatannol and analogs on the levels of prostate-specific antigen (PSA) in LNCaP cells and found that all studied compounds decreased the level of PSA and that the synthetic analogs diacetylresveratrol (RSVDA), triacetylresveratrol (RSVTA) and RSVTM were the most potent compounds, decreasing the PSA level by approx. 50% at concentrations ≥10μM. In a cell-free receptor binding assay we were unable to show binding of resveratrol or analogs to the ligand binding domain of the androgen receptor, indicating that the observed effects are mediated via other mechanisms than direct ligand competition. We conclude that the resveratrol

  14. Targeting the androgen receptor in triple-negative breast cancer: current perspectives

    Directory of Open Access Journals (Sweden)

    Mina A

    2017-09-01

    Full Text Available Alain Mina,1 Rachel Yoder,2 Priyanka Sharma1 1Division of Medical Oncology, Department of Internal Medicine, University of Kansas Medical Center, Westwood, 2University of Kansas Cancer Center, Kansas City, KS, USA Abstract: Triple-negative breast cancer (TNBC is an aggressive subtype associated with frequent recurrence and metastasis. Unlike hormone receptor-positive subtypes, treatment of TNBC is currently limited by the lack of clinically available targeted therapies. Androgen signaling is necessary for normal breast development, and its dysregulation has been implicated in breast tumorigenesis. In recent years, gene expression studies have identified a subset of TNBC that is enriched for androgen receptor (AR signaling. Interference with androgen signaling in TNBC is promising, and AR-inhibiting drugs have shown antitumorigenic activity in preclinical and proof of concept clinical studies. Recent advances in our understanding of androgenic signaling in TNBC, along with the identification of interacting pathways, are allowing development of the next generation of clinical trials with AR inhibitors. As novel AR-targeting agents are developed and evaluated in clinical trials, it is equally important to establish a robust set of biomarkers for identification of TNBC tumors that are most likely to respond to AR inhibition. Keywords: triple-negative breast cancer, androgen signaling, targeted therapy, biomarkers, prognosis 

  15. Development of cell-penetrating bispecific antibodies targeting the N-terminal domain of androgen receptor for prostate cancer therapy.

    Science.gov (United States)

    Goicochea, Nancy L; Garnovskaya, Maria; Blanton, Mary G; Chan, Grace; Weisbart, Richard; Lilly, Michael B

    2017-12-01

    Castration-resistant prostate cancer cells exhibit continued androgen receptor signaling in spite of low levels of ligand. Current therapies to block androgen receptor signaling act by inhibiting ligand production or binding. We developed bispecific antibodies capable of penetrating cells and binding androgen receptor outside of the ligand-binding domain. Half of the bispecific antibody molecule consists of a single-chain variable fragment of 3E10, an anti-DNA antibody that enters cells. The other half is a single-chain variable fragment version of AR441, an anti-AR antibody. The resulting 3E10-AR441 bispecific antibody enters human LNCaP prostate cells and accumulates in the nucleus. The antibody binds to wild-type, mutant and splice variant androgen receptor. Binding affinity of 3E10-AR441 to androgen receptor (284 nM) was lower than that of the parental AR441 mAb (4.6 nM), but could be improved (45 nM) through alternative placement of the affinity tags, and ordering of the VH and VK domains. The 3E10-AR441 bispecific antibody blocked genomic signaling by wild-type or splice variant androgen receptor in LNCaP cells. It also blocked non-genomic signaling by the wild-type receptor. Furthermore, bispecific antibody inhibited the growth of C4-2 prostate cancer cells under androgen-stimulated conditions. The 3E10-AR441 biAb can enter prostate cancer cells and inhibits androgen receptor function in a ligand-independent manner. It may be an attractive prototype agent for prostate cancer therapy. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. Development of an androgen reporter gene assay (AR-LUX) utilizing a human cell line with an endogenously regulated androgen receptor

    NARCIS (Netherlands)

    Blankvoort, B.M.G.; Groene, E.M. de; Meeteren-Kreikamp, A.P. van; Witkamp, R.F.; Rodenburg, R.J.T.; Aarts, J.M.M.J.G.

    2001-01-01

    The aim of the work described in this report is to develop and characterize a cell-based androgen reporter assay. For this purpose, the androgen receptor (AR) expressing human breast cancer cell line T47D was stably transfected with a luciferase gene under transcriptional control of the PB-ARE-2

  17. Cellular androgen content influences enzalutamide agonism of F877L mutant androgen receptor

    Science.gov (United States)

    Coleman, Daniel J.; Van Hook, Kathryn; King, Carly J.; Schwartzman, Jacob; Lisac, Robert; Urrutia, Joshua; Sehrawat, Archana; Woodward, Josha; Wang, Nicholas J.; Gulati, Roman; Thomas, George V.; Beer, Tomasz M.; Gleave, Martin; Korkola, James E.; Gao, Lina; Heiser, Laura M.; Alumkal, Joshi J.

    2016-01-01

    Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) – the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. PMID:27276681

  18. Androgen receptor signaling is required for androgen-sensitive human prostate cancer cell proliferation and survival

    Directory of Open Access Journals (Sweden)

    Day Wanda V

    2005-04-01

    Full Text Available Abstract Background Androgens and androgen receptors (AR regulate normal prostate development and growth. They also are involved in pathological development of prostatic diseases, including benign prostatic hyperplasia (BPH and prostate cancer (PCa. Antiandrogen therapy for PCa, in conjunction with chemical or surgical castration, offers initial positive responses and leads to massive prostate cell death. However, cancer cells later appear as androgen-independent PCa. To investigate the role of AR in prostate cell proliferation and survival, we introduced a vector-based small interfering RNA (siRNA. This siRNA targeted 5'-untranslated region of AR mRNA for extended suppression of AR expression in androgen-sensitive human prostate LNCaP cells. Results The siRNA design successfully suppressed endogenous AR expression, as revealed by western blotting and immunofluorescence staining in LNCaP cells. LNCaP cells did not proliferate in the absence of AR and underwent apoptosis, based on elevated phospho-Histone H2B expression and higher number of apoptotic body as compared to control cells. Conclusion We demonstrated that AR is vital for prostate cell proliferation and survival in this androgen-sensitive prostate cell line. These results further strengthen the hypothesis that AR can be a therapeutic target for treating androgen-sensitive stages of PCa. Unlike antiandorgens, however, siRNA targeting AR provides a direct inactivation of AR function through the suppression of AR protein expression.

  19. Effects of androgen on immunohistochemical localization of androgen receptor and Connexin 43 in mouse ovary.

    Science.gov (United States)

    Yang, Mei; Li, Jianhua; An, Yulin; Zhang, Shuiwen

    2015-10-01

    Androgens have essential roles in the regulation of follicular development and female fertility. Androgen excess is the leading defect in polycystic ovary syndrome (PCOS) patients and involved in the ovarian dysfunction. The aim of this study was to elucidate the regarding regulatory role of androgen in the follicular development of female mouse. Immunohistochemical staining and Western blot analyses were performed to detect androgen receptor (AR) and Connexin 43 (Cx43) expression in ovaries from both control and testosterone-treated group mice. In this study, localizations of AR and Cx43 were dramatically altered in testosterone-treated mouse ovaries. In addition, AR expression was significantly increased, whereas Cx43 expression was markedly decreased after testosterone treatment. Alterations of AR and Cx43 expression by testosterone with concomitant reduction of MII oocytes. Overall, these results suggest the involvement of androgen in the regulation of AR and Cx43 localizations in mouse ovary. Alterations of AR and Cx43 expression by testosterone may affect normal folliculogenesis. Together these findings will enable us to begin understanding the important roles of AR and Cx43 actions in the regulation of follicular development, as well as providing insights into the role of AR and Cx43 actions in the androgen-associated reproductive diseases such as PCOS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Targeting Alternative Sites on the Androgen Receptor to Treat Castration-Resistant Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Paul S. Rennie

    2013-06-01

    Full Text Available Recurrent, metastatic prostate cancer continues to be a leading cause of cancer-death in men. The androgen receptor (AR is a modular, ligand-inducible transcription factor that regulates the expression of genes that can drive the progression of this disease, and as a consequence, this receptor is a key therapeutic target for controlling prostate cancer. The current drugs designed to directly inhibit the AR are called anti-androgens, and all act by competing with androgens for binding to the androgen/ligand binding site. Unfortunately, with the inevitable progression of the cancer to castration resistance, many of these drugs become ineffective. However, there are numerous other regulatory sites on this protein that have not been exploited therapeutically. The regulation of AR activity involves a cascade of complex interactions with numerous chaperones, co-factors and co-regulatory proteins, leading ultimately to direct binding of AR dimers to specific DNA androgen response elements within the promoter and enhancers of androgen-regulated genes. As part of the family of nuclear receptors, the AR is organized into modular structural and functional domains with specialized roles in facilitating their inter-molecular interactions. These regions of the AR present attractive, yet largely unexploited, drug target sites for reducing or eliminating androgen signaling in prostate cancers. The design of small molecule inhibitors targeting these specific AR domains is only now being realized and is the culmination of decades of work, including crystallographic and biochemistry approaches to map the shape and accessibility of the AR surfaces and cavities. Here, we review the structure of the AR protein and describe recent advancements in inhibiting its activity with small molecules specifically designed to target areas distinct from the receptor’s androgen binding site. It is anticipated that these new classes of anti-AR drugs will provide an additional

  1. 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.

  2. 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.

  3. Identification of a novel androgen receptor agonist (or “androgen mimic”) of environmental concern: spironolactone

    Science.gov (United States)

    Spironolactone is a pharmaceutical that acts as an androgen receptor (AR) antagonist in humans to treat certain conditions such as hirsutism, various dermatologic afflictions, and female pattern hair loss. The drug is also used to treat hypertension as a diuretic. With this commo...

  4. The Androgen Receptor Gene Mutations Database.

    Science.gov (United States)

    Gottlieb, B; Lehvaslaiho, H; Beitel, L K; Lumbroso, R; Pinsky, L; Trifiro, M

    1998-01-01

    The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 272 to 309 in the past year. We have expanded the database: (i) by giving each entry an accession number; (ii) by adding information on the length of polymorphic polyglutamine (polyGln) and polyglycine (polyGly) tracts in exon 1; (iii) by adding information on large gene deletions; (iv) by providing a direct link with a completely searchable database (courtesy EMBL-European Bioinformatics Institute). The addition of the exon 1 polymorphisms is discussed in light of their possible relevance as markers for predisposition to prostate or breast cancer. The database is also available on the internet (http://www.mcgill. ca/androgendb/ ), from EMBL-European Bioinformatics Institute (ftp. ebi.ac.uk/pub/databases/androgen ), or as a Macintosh FilemakerPro or Word file (MC33@musica.mcgill.ca).

  5. Androgen receptor and histone lysine demethylases in ovine placenta.

    Directory of Open Access Journals (Sweden)

    Ellane R Cleys

    Full Text Available Sex steroid hormones regulate developmental programming in many tissues, including programming gene expression during prenatal development. While estradiol is known to regulate placentation, little is known about the role of testosterone and androgen signaling in placental development despite the fact that testosterone rises in maternal circulation during pregnancy and in placenta-induced pregnancy disorders. We investigated the role of testosterone in placental gene expression, and focused on androgen receptor (AR. Prenatal androgenization decreased global DNA methylation in gestational day 90 placentomes, and increased placental expression of AR as well as genes involved in epigenetic regulation, angiogenesis, and growth. As AR complexes with histone lysine demethylases (KDMs to regulate AR target genes in human cancers, we also investigated if the same mechanism is present in the ovine placenta. AR co-immunoprecipitated with KDM1A and KDM4D in sheep placentomes, and AR-KDM1A complexes were recruited to a half-site for androgen response element (ARE in the promoter region of VEGFA. Androgenized ewes also had increased cotyledonary VEGFA. Finally, in human first trimester placental samples KDM1A and KDM4D immunolocalized to the syncytiotrophoblast, with nuclear KDM1A and KDM4D immunostaining also present in the villous stroma. In conclusion, placental androgen signaling, possibly through AR-KDM complex recruitment to AREs, regulates placental VEGFA expression. AR and KDMs are also present in first trimester human placenta. Androgens appear to be an important regulator of trophoblast differentiation and placental development, and aberrant androgen signaling may contribute to the development of placental disorders.

  6. The promotion on cell growth of androgen-dependent prostate cancer by antimony via mimicking androgen activity.

    Science.gov (United States)

    Zhang, Changwen; Li, Penghao; Wen, Yingwu; Feng, Guowei; Liu, Yu; Zhang, Yangyi; Xu, Yong; Zhang, Zhihong

    2018-05-15

    Antimony is a widely used heavier pnictogens in industry, and its toxicity has been a matter of concern. Although previous studies have suggested that antimony may have the function as either a tumor suppressor or an oncogene in several cancers, the molecular basis underlying antimony-mediated transformation is still unclear. In the current study, we attempt to elucidate the potential role of antimony in the development of prostate cancer. Our results showed that the concentration of antimony was much higher in serum of prostate cancer patients, and was closely associated with poor outcome of patients who underwent radical prostatectomy. Additionally, low dose of antimony could promote proliferation and invasion of androgen-dependent prostate cancer cell line LNCaP cells in vitro and in vivo. The mechanistic studies demonstrated that exposure to antimony triggered the phosphorylation of androgen receptor (AR), which transcriptionally regulates the expression of androgen-related targets, including PSA and NKX3.1. Overall, our results unearthed that antimony could promote tumor growth by mimicking androgen activity in androgen-dependent prostate cancer cells. Therefore, these findings expanded our understanding on the molecular mechanism of antimony in tumorigenesis and tumor progression of prostate cancer, and it appears to be an inspiring strategy to restrain prostate cancer by inhibiting antimony-induced androgen-like effects. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Nonsteroidal selective androgen receptor modulators enhance female sexual motivation.

    Science.gov (United States)

    Jones, Amanda; Hwang, Dong Jin; Duke, Charles B; He, Yali; Siddam, Anjaiah; Miller, Duane D; Dalton, James T

    2010-08-01

    Women experience a decline in estrogen and androgen levels after natural or surgically induced menopause, effects that are associated with a loss of sexual desire and bone mineral density. Studies in our laboratories have shown the beneficial effects of selective androgen receptor modulators (SARMs) in the treatment of osteoporosis and muscle wasting in animal models. A series of S-3-(phenoxy)-2-hydroxy-2-methyl-N-(4-cyano-3-trifluoromethyl-phenyl)-propionamide analogs was synthesized to evaluate the effects of B-ring substitutions on in vitro and in vivo pharmacologic activity, especially female sexual motivation. The androgen receptor (AR) relative binding affinities ranged from 0.1 to 26.5% (relative to dihydrotestosterone) and demonstrated a range of agonist activity at 100 nM. In vivo pharmacologic activity was first assessed by using male rats. Structural modifications to the B-ring significantly affected the selectivity of the SARMs, demonstrating that single-atom substitutions can dramatically and unexpectedly influence activity in androgenic (i.e., prostate) and anabolic (i.e., muscle) tissues. (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro,4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide (S-23) displayed full agonist activity in androgenic and anabolic tissues; however, the remaining SARMs were more prostate-sparing, selectively maintaining the size of the levator ani muscle in castrated rats. The partner-preference paradigm was used to evaluate the effects of SARMs on female sexual motivation. With the exception of two four-halo substituted analogs, the SARMs increased sexual motivation in ovariectomized rats, with potency and efficacy comparable with testosterone propionate. These results indicate that the AR is important in regulating female libido given the nonaromatizable nature of SARMs and it could be a superior alternative to steroidal testosterone preparations in the treatment of hypoactive sexual desire disorder.

  8. Preventing the Androgen Receptor N/C Interaction Delays Disease Onset in a Mouse Model of SBMA

    Directory of Open Access Journals (Sweden)

    Lori Zboray

    2015-12-01

    Full Text Available Spinal and bulbar muscular atrophy (SBMA is a neurodegenerative disease caused by a polyglutamine expansion in the androgen receptor (AR and is associated with misfolding and aggregation of the mutant AR. We investigated the role of an interdomain interaction between the amino (N-terminal FxxLF motif and carboxyl (C-terminal AF-2 domain in a mouse model of SBMA. Male transgenic mice expressing polyQ-expanded AR with a mutation in the FxxLF motif (F23A to prevent the N/C interaction displayed substantially improved motor function compared with N/C-intact AR-expressing mice and showed reduced pathological features of SBMA. Serine 16 phosphorylation was substantially enhanced by the F23A mutation; moreover, the protective effect of AR F23A was dependent on this phosphorylation. These results reveal an important role for the N/C interaction on disease onset in mice and suggest that targeting AR conformation could be a therapeutic strategy for patients with SBMA.

  9. Structure of the ligand-binding domain (LBD) of human androgen receptor in complex with a selective modulator LGD2226

    International Nuclear Information System (INIS)

    Wang, Feng; Liu, Xiao-qin; Li, He; Liang, Kai-ni; Miner, Jeffrey N.; Hong, Mei; Kallel, E. Adam; Oeveren, Arjan van; Zhi, Lin; Jiang, Tao

    2006-01-01

    Crystal structure of the ligand-binding domain of androgen receptor in complex with LGD2226. The androgen receptor (AR) is a ligand-inducible steroid hormone receptor that mediates androgen action, determining male sexual phenotypes and promoting spermatogenesis. As the androgens play a dominant role in male sexual development and function, steroidal androgen agonists have been used clinically for some years. However, there is a risk of potential side effects and most steroidal androgens cannot be dosed orally, which limits the use of these substances. 1,2-Dihydro-6-N,N-bis(2,2,2-trifluoroethyl) amino-4-trifluoromethyl-2-quinolinone (LGD2226) is a synthetic nonsteroidal ligand and a novel selective AR modulator. The crystal structure of the complex of LGD2226 with the androgen receptor ligand-binding domain (AR LBD) at 2.1 Å was solved and compared with the structure of the AR LBD–R1881 complex. It is hoped that this will aid in further explaining the selectivity of LGD2226 observed in in vitro and in vivo assays and in developing more selective and effective therapeutic agents

  10. Characterization of niphatenones that inhibit androgen receptor N-terminal domain.

    Directory of Open Access Journals (Sweden)

    Carmen A Banuelos

    Full Text Available Androgen ablation therapy causes a temporary reduction in tumor burden in patients with advanced prostate cancer. Unfortunately the malignancy will return to form lethal castration-recurrent prostate cancer (CRPC. The androgen receptor (AR remains transcriptionally active in CRPC in spite of castrate levels of androgens in the blood. AR transcriptional activity resides in its N-terminal domain (NTD. Possible mechanisms of continued AR transcriptional activity may include, at least in part, expression of constitutively active splice variants of AR that lack the C-terminal ligand-binding domain (LBD. Current therapies that target the AR LBD, would not be effective against these AR variants. Currently no drugs are clinically available that target the AR NTD which should be effective against these AR variants as well as full-length AR. Niphatenones were originally isolated and identified in active extracts from Niphates digitalis marine sponge. Here we begin to characterize the mechanism of niphatenones in blocking AR transcriptional activity. Both enantiomers had similar IC50 values of 6 µM for inhibiting the full-length AR in a functional transcriptional assay. However, (S-niphatenone had significantly better activity against the AR NTD compared to (R-niphatenone. Consistent with niphatenones binding to and inhibiting transactivation of AR NTD, niphatenones inhibited AR splice variant. Niphatenone did not affect the transcriptional activity of the related progesterone receptor, but slightly decreased glucocorticoid receptor (GR activity and covalently bound to GR activation function-1 (AF-1 region. Niphatenone blocked N/C interactions of AR without altering either AR protein levels or its intracellular localization in response to androgen. Alkylation with glutathione suggests that niphatenones are not a feasible scaffold for further drug development.

  11. Testicular development in mice lacking receptors for follicle stimulating hormone and androgen.

    Directory of Open Access Journals (Sweden)

    Peter J O'Shaughnessy

    Full Text Available Post-natal testicular development is dependent on gonadotrophin and androgen stimulation. Follicle stimulating hormone (FSH acts through receptors (FSHR on the Sertoli cell to stimulate spermatogenesis while androgens promote testis growth through receptors (AR on the Sertoli cells, Leydig cells and peritubular myoid cells. In this study we have examined the effects on testis development of ablating FSHRs (FSHRKO mice and/or ARs ubiquitously (ARKO mice or specifically on the Sertoli cells (SCARKO mice. Cell numbers were measured using stereological methods. In ARKO mice Sertoli cell numbers were reduced at all ages from birth until adulthood. FSHR ablation also caused small reductions in Sertoli cell numbers up to day 20 with more marked effects seen in the adult. Germ cell numbers were unaffected by FSHR and/or AR ablation at birth. By day 20 ubiquitous AR or FSHR ablation caused a marked reduction in germ cell numbers with a synergistic effect of losing both receptors (germ cell numbers in FSHRKO.ARKO mice were 3% of control. Germ cell numbers in SCARKO mice were less affected. By adulthood, in contrast, clear synergistic control of germ cell numbers had become established between the actions of FSH and androgen through the Sertoli cells. Leydig cell numbers were normal on day 1 and day 5 in all groups. By day 20 and in adult animals total AR or FSHR ablation significantly reduced Leydig cell numbers but Sertoli cell specific AR ablation had no effect. Results show that, prior to puberty, development of most testicular parameters is more dependent on FSH action than androgen action mediated through the Sertoli cells although androgen action through other cells types is crucial. Post-pubertally, germ cell numbers and spermatogenesis are dependent on FSH and androgen action through the Sertoli cells.

  12. Long-lasting masculinizing effects of postnatal androgens on myelin governed by the brain androgen receptor

    Science.gov (United States)

    Abi Ghanem, Charly; Degerny, Cindy; Hussain, Rashad; Liere, Philippe; Pianos, Antoine; Tourpin, Sophie; Habert, René; Schumacher, Michael

    2017-01-01

    The oligodendrocyte density is greater and myelin sheaths are thicker in the adult male mouse brain when compared with females. Here, we show that these sex differences emerge during the first 10 postnatal days, precisely at a stage when a late wave of oligodendrocyte progenitor cells arises and starts differentiating. Androgen levels, analyzed by gas chromatography/tandem-mass spectrometry, were higher in males than in females during this period. Treating male pups with flutamide, an androgen receptor (AR) antagonist, or female pups with 5α-dihydrotestosterone (5α-DHT), revealed the importance of postnatal androgens in masculinizing myelin and their persistent effect into adulthood. A key role of the brain AR in establishing the sexual phenotype of myelin was demonstrated by its conditional deletion. Our results uncover a new persistent effect of postnatal AR signaling, with implications for neurodevelopmental disorders and sex differences in multiple sclerosis. PMID:29107990

  13. Expression and function of androgen receptor coactivator p44/Mep50/WDR77 in ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Martin Ligr

    Full Text Available Hormones, including estrogen and progesterone, and their receptors play an important role in the development and progression of ovarian carcinoma. Androgen, its receptor and coactivators have also been implicated in these processes. p44/Mep50/WDR77 was identified as a subunit of the methylosome complex and lately characterized as a steroid receptor coactivator that enhances androgen receptor as well as estrogen receptor-mediated transcriptional activity in a ligand-dependent manner. We previously described distinct expression and function of p44 in prostate, testis, and breast cancers. In this report, we examined the expression and function of p44 in ovarian cancer. In contrast to findings in prostate and testicular cancer and similar to breast cancer, p44 shows strong cytoplasmic localization in morphologically normal ovarian surface and fallopian tube epithelia, while nuclear p44 is observed in invasive ovarian carcinoma. We observed that p44 can serve as a coactivator of both androgen receptor (AR and estrogen receptor (ER in ovarian cells. Further, overexpression of nuclear-localized p44 stimulates proliferation and invasion in ovarian cancer cells in the presence of estrogen or androgen. These findings strongly suggest that p44 plays a role in mediating the effects of hormones during ovarian tumorigenesis.

  14. Pharmacological characterization of an imidazolopyrazole as novel selective androgen receptor modulator.

    Science.gov (United States)

    Zhang, Xuqing; Allan, George F; Tannenbaum, Pamela; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Lundeen, Scott G; Sui, Zhihua

    2013-03-01

    Selective androgen receptor modulators (SARMs) are androgens with tissue-selective activity. SARMs that have anabolic activity on muscle while having minimal stimulatory activity on prostate are classified as SARM agonists. They can be used to prevent the loss of lean body mass that is associated with cancer, immunodeficiency, renal disease and aging. They may also have anabolic activity on bone; thus, unlike estrogens, they may reverse the loss of bone strength associated with aging or hypogonadism. Our in-house effort on SARM program discovers a nonsteroidal androgen receptor ligand with a unique imidazolopyrazole moiety in its structure. In vitro, this compound is a weak androgen receptor binder and a weak androgen agonist. Despite this, in orchidectomized mature rats it is an effective SARM agonist, with an ED(50) on levator ani muscle of 3.3mg/kg and an ED(50) on ventral prostate of >30mg/kg. It has its maximal effect on muscle at the dose of 10mg/kg. In addition, this compound has mixed agonistic and antagonistic activities on prostate, reducing the weight of that tissue in intact rats by 22% at 10mg/kg. The compound does not have significant effect on gonadotropin levels or testosterone levels in both orchidectomized and intact male rats. It does not have notable progestin, estrogen or glucocorticoid agonistic or antagonistic activity in rats. In a female sexual behavior model, it improves the sexual desire of ovariectomized female rats for sexually mature intact males over nonsexually ovariectomized females. Overall, the imidazolopyrazole is a potent prostate-sparing candidate for development as a SARM agonist with an appropriate pharmacological profile for clinical benefit in muscle-wasting conditions and female sexual function disorders. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. The role of GH receptor tyrosine phosphorylation in Stat5 activation

    DEFF Research Database (Denmark)

    Hansen, J A; Hansen, L H; Wang, X

    1997-01-01

    Stimulation of GH receptors leads to rapid activation of Jak2 kinase and subsequent tyrosine phosphorylation of the GH receptor. Three specific tyrosines located in the C-terminal domain of the GH receptor have been identified as being involved in GH-stimulated transcription of the Spi 2.1 promoter....... Mutated GH receptors lacking all but one of these three tyrosines are able to mediate a transcriptional response when transiently transfected into CHO cells together with a Spi 2.1 promoter/luciferase construct. Similarly, these GH receptors were found to be able to mediate activation of Stat5 DNA......-binding activity, whereas the GH receptor mutant lacking all intracellular tyrosines was not. Synthetic tyrosine phosphorylated peptides corresponding to the GH receptor sequence around the three tyrosines inhibited Stat5 DNA-binding activity while their non-phosphorylated counterparts were ineffective. Tyrosine...

  16. Gene expression profiling of the androgen receptor antagonists flutamide and vinclozolin in zebrafish (Danio rerio) gonads

    International Nuclear Information System (INIS)

    Martinovic-Weigelt, Dalma; Wang Ronglin; Villeneuve, Daniel L.; Bencic, David C.; Lazorchak, Jim; Ankley, Gerald T.

    2011-01-01

    The studies presented in this manuscript focus on characterization of transcriptomic responses to anti-androgens in zebrafish (Danio rerio). Research on the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of action (MOA) of anti-androgens remain poorly elucidated. In the present study, we examined effects of a short term exposure (24-96 h) to the androgen receptor antagonists flutamide (FLU) and vinclozolin (VZ) on gene expression in gonads of sexually mature zebrafish, using commercially available zebrafish oligonucleotide microarrays (4 x 44 K platform). We found that VZ and FLU potentially impact reproductive processes via multiple pathways related to steroidogenesis, spermatogenesis, and fertilization. Observed changes in gene expression often were shared by VZ and FLU, as demonstrated by overlap in differentially-expressed genes and enrichment of several common key pathways including: (1) integrin and actin signaling, (2) nuclear receptor 5A1 signaling, (3) fibroblast growth factor receptor signaling, (4) polyamine synthesis, and (5) androgen synthesis. This information should prove useful to elucidating specific mechanisms of reproductive effects of anti-androgens in fish, as well as developing biomarkers for this important class of endocrine-active chemicals.

  17. Gene expression profiling of the androgen receptor antagonists flutamide and vinclozolin in zebrafish (Danio rerio) gonads

    Energy Technology Data Exchange (ETDEWEB)

    Martinovic-Weigelt, Dalma, E-mail: dalma@stthomas.edu [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States); University of St. Thomas, 2115 Summit Ave, Saint Paul, MN 55105 (United States); Wang Ronglin [US Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Ecological Exposure Research Division, 26W. Martin Luther King Dr., Cincinnati, OH 45268 (United States); Villeneuve, Daniel L. [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States); Bencic, David C.; Lazorchak, Jim [US Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Ecological Exposure Research Division, 26W. Martin Luther King Dr., Cincinnati, OH 45268 (United States); Ankley, Gerald T. [US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd., Duluth, MN 55804 (United States)

    2011-01-25

    The studies presented in this manuscript focus on characterization of transcriptomic responses to anti-androgens in zebrafish (Danio rerio). Research on the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of action (MOA) of anti-androgens remain poorly elucidated. In the present study, we examined effects of a short term exposure (24-96 h) to the androgen receptor antagonists flutamide (FLU) and vinclozolin (VZ) on gene expression in gonads of sexually mature zebrafish, using commercially available zebrafish oligonucleotide microarrays (4 x 44 K platform). We found that VZ and FLU potentially impact reproductive processes via multiple pathways related to steroidogenesis, spermatogenesis, and fertilization. Observed changes in gene expression often were shared by VZ and FLU, as demonstrated by overlap in differentially-expressed genes and enrichment of several common key pathways including: (1) integrin and actin signaling, (2) nuclear receptor 5A1 signaling, (3) fibroblast growth factor receptor signaling, (4) polyamine synthesis, and (5) androgen synthesis. This information should prove useful to elucidating specific mechanisms of reproductive effects of anti-androgens in fish, as well as developing biomarkers for this important class of endocrine-active chemicals.

  18. Regulation of protein kinase C-related kinase (PRK) signalling by the TPα and TPβ isoforms of the human thromboxane A2 receptor: Implications for thromboxane- and androgen- dependent neoplastic and epigenetic responses in prostate cancer.

    Science.gov (United States)

    O'Sullivan, Aine G; Mulvaney, Eamon P; Kinsella, B Therese

    2017-04-01

    The prostanoid thromboxane (TX) A 2 and its T Prostanoid receptor (the TP) are increasingly implicated in prostate cancer (PCa). Mechanistically, we recently discovered that both TPα and TPβ form functional signalling complexes with members of the protein kinase C-related kinase (PRK) family, AGC- kinases essential for the epigenetic regulation of androgen receptor (AR)-dependent transcription and promising therapeutic targets for treatment of castrate-resistant prostate cancer (CRPC). Critically, similar to androgens, activation of the PRKs through the TXA 2 /TP signalling axis induces phosphorylation of histone H3 at Thr11 (H3Thr11), a marker of androgen-induced chromatin remodelling and transcriptional activation, raising the possibility that TXA 2 -TP signalling can mimic and/or enhance AR-induced cellular changes even in the absence of circulating androgens such as in CRPC. Hence the aim of the current study was to investigate whether TXA 2 /TP-induced PRK activation can mimic and/or enhance AR-mediated cellular responses in the model androgen-responsive prostate adenocarcinoma LNCaP cell line. We reveal that TXA 2 /TP signalling can act as a neoplastic- and epigenetic-regulator, promoting and enhancing both AR-associated chromatin remodelling (H3Thr11 phosphorylation, WDR5 recruitment and acetylation of histone H4 at lysine 16) and AR-mediated transcriptional activation (e.g of the KLK3/prostate-specific antigen and TMPRSS2 genes) through mechanisms involving TPα/TPβ mediated-PRK1 and PRK2, but not PRK3, signalling complexes. Overall, these data demonstrate that TPα/TPβ can act as neoplastic and epigenetic regulators by mimicking and/or enhancing the actions of androgens within the prostate and provides further mechanistic insights into the role of the TXA 2 /TP signalling axis in PCa, including potentially in CRPC. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Androgen receptor polyglutamine repeat length (AR-CAGn) modulates the effect of testosterone on androgen-associated somatic traits in Filipino young adult men.

    Science.gov (United States)

    Ryan, Calen P; Georgiev, Alexander V; McDade, Thomas W; Gettler, Lee T; Eisenberg, Dan T A; Rzhetskaya, Margarita; Agustin, Sonny S; Hayes, M Geoffrey; Kuzawa, Christopher W

    2017-06-01

    The androgen receptor (AR) mediates expression of androgen-associated somatic traits such as muscle mass and strength. Within the human AR is a highly variable glutamine short-tandem repeat (AR-CAGn), and CAG repeat number has been inversely correlated to AR transcriptional activity in vitro. However, evidence for an attenuating effect of long AR-CAGn on androgen-associated somatic traits has been inconsistent in human populations. One possible explanation for this lack of consistency is that the effect of AR-CAGn on AR bioactivity in target tissues likely varies in relation to circulating androgen levels. We tested whether relationships between AR-CAGn and several androgen-associated somatic traits (waist circumference, lean mass, arm muscle area, and grip strength) were modified by salivary (waking and pre-bed) and circulating (total) testosterone (T) levels in young adult males living in metropolitan Cebu, Philippines (n = 675). When men's waking T was low, they had a reduction in three out of four androgen-associated somatic traits with lengthening AR-CAGn (p AR-CAGn was associated with an increase in these same somatic traits. Our finding that longer AR-CAGn predicts greater androgen-associated trait expression among high-T men runs counter to in vitro work, but is generally consistent with the few prior studies to evaluate similar interactions in human populations. Collectively, these results raise questions about the applicability of findings derived from in vitro AR-CAGn studies to the receptor's role in maintaining androgen-associated somatic traits in human populations. © 2017 Wiley Periodicals, Inc.

  20. G Protein-coupled Receptor Kinases of the GRK4 Protein Subfamily Phosphorylate Inactive G Protein-coupled Receptors (GPCRs).

    Science.gov (United States)

    Li, Lingyong; Homan, Kristoff T; Vishnivetskiy, Sergey A; Manglik, Aashish; Tesmer, John J G; Gurevich, Vsevolod V; Gurevich, Eugenia V

    2015-04-24

    G protein-coupled receptor (GPCR) kinases (GRKs) play a key role in homologous desensitization of GPCRs. It is widely assumed that most GRKs selectively phosphorylate only active GPCRs. Here, we show that although this seems to be the case for the GRK2/3 subfamily, GRK5/6 effectively phosphorylate inactive forms of several GPCRs, including β2-adrenergic and M2 muscarinic receptors, which are commonly used as representative models for GPCRs. Agonist-independent GPCR phosphorylation cannot be explained by constitutive activity of the receptor or membrane association of the GRK, suggesting that it is an inherent ability of GRK5/6. Importantly, phosphorylation of the inactive β2-adrenergic receptor enhanced its interactions with arrestins. Arrestin-3 was able to discriminate between phosphorylation of the same receptor by GRK2 and GRK5, demonstrating preference for the latter. Arrestin recruitment to inactive phosphorylated GPCRs suggests that not only agonist activation but also the complement of GRKs in the cell regulate formation of the arrestin-receptor complex and thereby G protein-independent signaling. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Stromal Androgen Receptor in Prostate Cancer Development and Progression

    Science.gov (United States)

    Leach, Damien A.; Buchanan, Grant

    2017-01-01

    Prostate cancer development and progression is the result of complex interactions between epithelia cells and fibroblasts/myofibroblasts, in a series of dynamic process amenable to regulation by hormones. Whilst androgen action through the androgen receptor (AR) is a well-established component of prostate cancer biology, it has been becoming increasingly apparent that changes in AR signalling in the surrounding stroma can dramatically influence tumour cell behavior. This is reflected in the consistent finding of a strong association between stromal AR expression and patient outcomes. In this review, we explore the relationship between AR signalling in fibroblasts/myofibroblasts and prostate cancer cells in the primary site, and detail the known functions, actions, and mechanisms of fibroblast AR signaling. We conclude with an evidence-based summary of how androgen action in stroma dramatically influences disease progression. PMID:28117763

  2. Study the Origin and Mechanisms of Castration Resistance Characterized by Outgrowth of Prostate Cancer Cells with Low/Negative Androgen Receptor

    Science.gov (United States)

    2017-12-01

    Prostate Cancer Cells with Low/Negative Androgen Receptor 5b. GRANT NUMBER W81XWH-15-1-0540 5c. PROGRAM...role of androgen receptor (AR) signaling in disease progression, the current approach to treat prostate cancer is AR-targeted therapy. While this... Prostate cancer ; Androgen receptor ; Castration-resistant prostate cancer (CRPC); Enzalutamide resistance; GREB1; p300 6 Accomplishments Specific

  3. Testosterone-Dependent Interaction between Androgen Receptor and Aryl Hydrocarbon Receptor Induces Liver Receptor Homolog 1 Expression in Rat Granulosa Cells

    Science.gov (United States)

    Wu, Yanguang; Baumgarten, Sarah C.; Zhou, Ping

    2013-01-01

    Androgens play a major role in the regulation of normal ovarian function; however, they are also involved in the development of ovarian pathologies. These contrasting effects may involve a differential response of granulosa cells to the androgens testosterone (T) and dihydrotestosterone (DHT). To determine the molecular pathways that mediate the distinct effects of T and DHT, we studied the expression of the liver receptor homolog 1 (LRH-1) gene, which is differentially regulated by these steroids. We found that although both T and DHT stimulate androgen receptor (AR) binding to the LRH-1 promoter, DHT prevents T-mediated stimulation of LRH-1 expression. T stimulated the expression of aryl hydrocarbon receptor (AHR) and its interaction with the AR. T also promoted the recruitment of the AR/AHR complex to the LRH-1 promoter. These effects were not mimicked by DHT. We also observed that the activation of extracellular regulated kinases by T is required for AR and AHR interaction. In summary, T, but not DHT, stimulates AHR expression and the interaction between AHR and AR, leading to the stimulation of LRH-1 expression. These findings could explain the distinct response of granulosa cells to T and DHT and provide a molecular mechanism by which DHT negatively affects ovarian function. PMID:23689136

  4. Polymorphisms in the vitamin D receptor gene and the androgen receptor gene and the risk of benign prostatic hyperplasia

    NARCIS (Netherlands)

    Bousema, J. T.; Bussemakers, M. J.; van Houwelingen, K. P.; Debruyne, F. M.; Verbeek, A. L.; de la Rosette, J. J.; Kiemeney, L. A.

    2000-01-01

    Little is known about risk factors for the development of benign prostatic hyperplasia (BPH). Recently, associations were observed between prostate cancer (CaP) risk and polymorphisms in the vitamin D receptor (VDR) gene and the androgen receptor (AR) gene. Since both receptors are relevant for

  5. Gene expression profiling of the androgen receptor antagonists flutamide and vinclozolin in zebrafish (Danio rerio) gonads.

    Science.gov (United States)

    Martinović-Weigelt, Dalma; Wang, Rong-Lin; Villeneuve, Daniel L; Bencic, David C; Lazorchak, Jim; Ankley, Gerald T

    2011-01-25

    The studies presented in this manuscript focus on characterization of transcriptomic responses to anti-androgens in zebrafish (Danio rerio). Research on the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of action (MOA) of anti-androgens remain poorly elucidated. In the present study, we examined effects of a short term exposure (24-96h) to the androgen receptor antagonists flutamide (FLU) and vinclozolin (VZ) on gene expression in gonads of sexually mature zebrafish, using commercially available zebrafish oligonucleotide microarrays (4×44K platform). We found that VZ and FLU potentially impact reproductive processes via multiple pathways related to steroidogenesis, spermatogenesis, and fertilization. Observed changes in gene expression often were shared by VZ and FLU, as demonstrated by overlap in differentially-expressed genes and enrichment of several common key pathways including: (1) integrin and actin signaling, (2) nuclear receptor 5A1 signaling, (3) fibroblast growth factor receptor signaling, (4) polyamine synthesis, and (5) androgen synthesis. This information should prove useful to elucidating specific mechanisms of reproductive effects of anti-androgens in fish, as well as developing biomarkers for this important class of endocrine-active chemicals. 2010 Elsevier B.V. All rights reserved.

  6. Changes in amount and intracellular distribution of androgen receptor in human foreskin as a function of age.

    Science.gov (United States)

    Roehrborn, C G; Lange, J L; George, F W; Wilson, J D

    1987-01-01

    To provide insight into the factors that control growth of the penis we measured the amount and intracellular distribution of specific high affinity androgen receptor in foreskins obtained at circumcision from 49 males varying in age from newborn to 59 yr. Total (cytosolic plus nuclear extract) androgen receptor decreased from approximately 40 fmol/g tissue weight in newborn foreskins to approximately 25 fmol/g by 1 yr of age. The amount of receptor rose in childhood to approximately 180 fmol/g in the late teenage years and fell thereafter to approximately 20-40 fmol/g in men older than 40 yr. The amount of receptor in the nuclear fraction increased at the time of puberty and subsequently decreased in parallel with the decline in total receptor level. These changes in androgen-receptor amount are similar when expressed per milligram DNA or per milligram protein. Images PMID:3491838

  7. Stress induces pain transition by potentiation of AMPA receptor phosphorylation.

    Science.gov (United States)

    Li, Changsheng; Yang, Ya; Liu, Sufang; Fang, Huaqiang; Zhang, Yong; Furmanski, Orion; Skinner, John; Xing, Ying; Johns, Roger A; Huganir, Richard L; Tao, Feng

    2014-10-08

    Chronic postsurgical pain is a serious issue in clinical practice. After surgery, patients experience ongoing pain or become sensitive to incident, normally nonpainful stimulation. The intensity and duration of postsurgical pain vary. However, it is unclear how the transition from acute to chronic pain occurs. Here we showed that social defeat stress enhanced plantar incision-induced AMPA receptor GluA1 phosphorylation at the Ser831 site in the spinal cord and greatly prolonged plantar incision-induced pain. Interestingly, targeted mutation of the GluA1 phosphorylation site Ser831 significantly inhibited stress-induced prolongation of incisional pain. In addition, stress hormones enhanced GluA1 phosphorylation and AMPA receptor-mediated electrical activity in the spinal cord. Subthreshold stimulation induced spinal long-term potentiation in GluA1 phosphomimetic mutant mice, but not in wild-type mice. Therefore, spinal AMPA receptor phosphorylation contributes to the mechanisms underlying stress-induced pain transition. Copyright © 2014 the authors 0270-6474/14/3413737-10$15.00/0.

  8. 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.

  9. Nuclear androgen receptors in human prostatic tissue. Extraction with heparin and estimation of the number of binding sites with different methods

    International Nuclear Information System (INIS)

    Foekens, J.A.; Bolt-de Vries, J.; Mulder, E.; Blankenstein, M.A.; Schroeder, F.H.; Molen, H.J. van der

    1981-01-01

    A procedure for the estimation of nuclear androgen receptors in benign prostatic hyperplastic tissue is described, which employs extraction of receptors from nuclei with buffers containing heparin. Extraction of a nuclear pellet with a heparin-containing (1 g/l) buffer appeared to have definite advantages over 0.4 mol/l KCl extraction. Heparin appeared to be twice as efficient in extracting androgen receptors. In addition aggregated receptor proteins, formed after storage at -80 0 C, were partly deaggregated by heparin. Specific isolation of the androgen receptor was performed using either agar gel electrophoresis, protamine sulphate precipitation or LH-20 gel filtration. A comparison was made between the amounts of estimated receptors with these different techniques. Protamine sulphate precipitation resulted in the highest estimates of receptor-bound 5α-[ 3 H]dihydrotestosterone ( 3 H-DHT). Treatment of the labelled nuclear extracts with a charcoal suspension prior to the receptor assay resulted in lower amounts of estimated androgen receptors. A method for routine evaluation of nuclear androgen receptors in prostatic tissue has been evaluated, which involves extraction of nuclear pellets with a heparin-containing (1 g/l) buffer, exchange labelling of the nuclear extracts for 20 h at 10 0 C and quantification of the receptors with protamine sulphate precipitation. (Auth.)

  10. Advantages and Limitations of Androgen Receptor-Based Methods for Detecting Anabolic Androgenic Steroid Abuse as Performance Enhancing Drugs

    Science.gov (United States)

    Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred

    2016-01-01

    Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete’s urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as ‘T-equivalent’ concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact. PMID:26998755

  11. Advantages and Limitations of Androgen Receptor-Based Methods for Detecting Anabolic Androgenic Steroid Abuse as Performance Enhancing Drugs.

    Science.gov (United States)

    Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred

    2016-01-01

    Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete's urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as 'T-equivalent' concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact.

  12. Minoxidil may suppress androgen receptor-related functions.

    Science.gov (United States)

    Hsu, Cheng-Lung; Liu, Jai-Shin; Lin, An-Chi; Yang, Chih-Hsun; Chung, Wen-Hung; Wu, Wen-Guey

    2014-04-30

    Although minoxidil has been used for more than two decades to treat androgenetic alopecia (AGA), an androgen-androgen receptor (AR) pathway-dominant disease, its precise mechanism of action remains elusive. We hypothesized that minoxidil may influence the AR or its downstream signaling. These tests revealed that minoxidil suppressed AR-related functions, decreasing AR transcriptional activity in reporter assays, reducing expression of AR targets at the protein level, and suppressing AR-positive LNCaP cell growth. Dissecting the underlying mechanisms, we found that minoxidil interfered with AR-peptide, AR-coregulator, and AR N/C-terminal interactions, as well as AR protein stability. Furthermore, a crystallographic analysis using the AR ligand-binding domain (LBD) revealed direct binding of minoxidil to the AR in a minoxidil-AR-LBD co-crystal model, and surface plasmon resonance assays demonstrated that minoxidil directly bound the AR with a K(d) value of 2.6 µM. Minoxidil also suppressed AR-responsive reporter activity and decreased AR protein stability in human hair dermal papilla cells. The current findings provide evidence that minoxidil could be used to treat both cancer and age-related disease, and open a new avenue for applications of minoxidil in treating androgen-AR pathway-related diseases.

  13. BAF57 Modulation of Androgen Receptor Action and Prostate Cancer Progression

    National Research Council Canada - National Science Library

    Link, Kevin A

    2007-01-01

    Given the requirement of the androgen receptor (AR) activation pathway for prostate cancer growth and progression, it is necessary to identify alternative means of targeting this pathway for the treatment of prostate cancer...

  14. Identification of steroid-binding and phosphorylated sites within the glucocorticoid receptor

    International Nuclear Information System (INIS)

    Smith, L.I.

    1989-01-01

    The primary goal of these studies was to localize the steroid-binding and phosphorylated sites of the glucocorticoid receptor. The synthetic steroid, dexamethasone 21-mesylate (DM) forms a covalent thioether bond via the sulfhydryl group of a cysteine residue in the receptor. To determine the covalent site of attachment of this ligand, receptors in WEHI-7 mouse thymoma cells were labeled with [ 3 H]DM and purified with a monoclonal antibody. The receptor was completely digested with trypsin and a single peptide covalently labeled with steroid identified by reversed-phase HPLC. This peptide was analyzed by automated Edman degradation to determine the location of the steroid-labeled residue. A similar analysis was performed on an overlapping peptide produced by Staphylococcus aureus protease digestion. Analysis of tryptic peptides from receptors labeled with both [ 3 H]DM and L-[ 35 S]methionine indicated that this peptide contained methionine. These analyses, coupled with the published amino acid sequence of the receptor, identified Cysteine-644 in the steroid-binding domain of the mouse glucocorticoid receptor as the residue involved in covalent steroid-binding. A synthetic peptide representing amino acids 640-650 of the mouse receptor was prepared and analyzed to confirm the identification. These biochemical studies represent a direct demonstration of an amino acid important in receptor function. It has been proposed that the receptor functions through a phosphorylation-dephosphorylation cycle to explain the dependence of hormone binding capacity upon cellular ATP. The glucocorticoid receptor has been shown to be a phosphoprotein. As an initial step to identifying a role of phosphorylation in receptor action, phosphorylated sites within the functional domains of the protein were identified

  15. Epigenetic Machinery Regulates Alternative Splicing of Androgen Receptor (AR) Gene in Castration-Resistant Prostate Cancer (CRPC)

    Science.gov (United States)

    2017-09-01

    Splicing of Androgen Receptor (AR) Gene in Castration-Resistant Prostate Cancer (CRPC) 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Jer...Epigenetic regulation of androgen receptor signaling in prostate cancer . Epigenetics. 5, 100-104. 2. Duan LL, Rai G , Roggero C, Zhang Q-J, Wei Q... Prostate Cancer (CRPC) PRINCIPAL INVESTIGATOR: Hsieh, Jer-Tsong CONTRACTING ORGANIZATION: University of Texas Southwestern Medical Center

  16. A selective androgen receptor modulator for hormonal male contraception.

    Science.gov (United States)

    Chen, Jiyun; Hwang, Dong Jin; Bohl, Casey E; Miller, Duane D; Dalton, James T

    2005-02-01

    The recent discovery of nonsteroidal selective androgen receptor modulators (SARMs) provides a promising alternative for testosterone replacement therapies, including hormonal male contraception. The identification of an orally bioavailable SARM with the ability to mimic the central and peripheral androgenic and anabolic effects of testosterone would represent an important step toward the "male pill". We characterized the in vitro and in vivo pharmacologic activity of (S)-3-(4-chloro-3-fluorophenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethylphenyl)propionamide (C-6), a novel SARM developed in our laboratories. C-6 was identified as an androgen receptor (AR) agonist with high AR binding affinity (K(i) = 4.9 nM). C-6 showed tissue-selective pharmacologic activity with higher anabolic activity than androgenic activity in male rats. The doses required to maintain the weight of the prostate, seminal vesicles, and levator ani muscle to half the size of the maximum effects (i.e., ED(50)) were 0.78 +/- 0.06, 0.88 +/- 0.1, and 0.17 +/- 0.04 mg/day, respectively. As opposed to other SARMs, gonadotropin levels in C-6-treated groups were significantly lower than control values. C-6 also significantly decreased serum testosterone concentration in intact rats after 2 weeks of treatment. Marked suppression of spermatogenesis was observed after 10 weeks of treatment with C-6 in intact male rats. Pharmacokinetic studies of C-6 in male rats revealed that C-6 was well absorbed after oral administration (bioavailability 76%), with a long (6.3 h) half-life at a dose of 10 mg/kg. These studies show that C-6 mimicked the in vivo pharmacologic and endocrine effects of testosterone while maintaining the oral bioavailability and tissue-selective actions of nonsteroidal SARMs.

  17. Selective Androgen Receptor Down-Regulators (SARDs): A New Prostate Cancer Therapy

    National Research Council Canada - National Science Library

    Bhattacharyya, Rumi S

    2007-01-01

    The androgen receptor (AR) plays a key role in the development and progression of prostate cancer Targeting the AR for down-regulation would be a useful strategy for treating prostate cancer, especially hormone-refractory...

  18. Effect of B-ring substitution pattern on binding mode of propionamide selective androgen receptor modulators.

    Science.gov (United States)

    Bohl, Casey E; Wu, Zengru; Chen, Jiyun; Mohler, Michael L; Yang, Jun; Hwang, Dong Jin; Mustafa, Suni; Miller, Duane D; Bell, Charles E; Dalton, James T

    2008-10-15

    Selective androgen receptor modulators (SARMs) are essentially prostate sparing androgens, which provide therapeutic potential in osteoporosis, male hormone replacement, and muscle wasting. Herein we report crystal structures of the androgen receptor (AR) ligand-binding domain (LBD) complexed to a series of potent synthetic nonsteroidal SARMs with a substituted pendant arene referred to as the B-ring. We found that hydrophilic B-ring para-substituted analogs exhibit an additional region of hydrogen bonding not seen with steroidal compounds and that multiple halogen substitutions affect the B-ring conformation and aromatic interactions with Trp741. This information elucidates interactions important for high AR binding affinity and provides new insight for structure-based drug design.

  19. Kinome analysis of receptor-induced phosphorylation in human natural killer cells.

    Directory of Open Access Journals (Sweden)

    Sebastian König

    Full Text Available BACKGROUND: Natural killer (NK cells contribute to the defense against infected and transformed cells through the engagement of multiple germline-encoded activation receptors. Stimulation of the Fc receptor CD16 alone is sufficient for NK cell activation, whereas other receptors, such as 2B4 (CD244 and DNAM-1 (CD226, act synergistically. After receptor engagement, protein kinases play a major role in signaling networks controlling NK cell effector functions. However, it has not been characterized systematically which of all kinases encoded by the human genome (kinome are involved in NK cell activation. RESULTS: A kinase-selective phosphoproteome approach enabled the determination of 188 kinases expressed in human NK cells. Crosslinking of CD16 as well as 2B4 and DNAM-1 revealed a total of 313 distinct kinase phosphorylation sites on 109 different kinases. Phosphorylation sites on 21 kinases were similarly regulated after engagement of either CD16 or co-engagement of 2B4 and DNAM-1. Among those, increased phosphorylation of FYN, KCC2G (CAMK2, FES, and AAK1, as well as the reduced phosphorylation of MARK2, were reproducibly observed both after engagement of CD16 and co-engagement of 2B4 and DNAM-1. Notably, only one phosphorylation on PAK4 was differentally regulated. CONCLUSIONS: The present study has identified a significant portion of the NK cell kinome and defined novel phosphorylation sites in primary lymphocytes. Regulated phosphorylations observed in the early phase of NK cell activation imply these kinases are involved in NK cell signaling. Taken together, this study suggests a largely shared signaling pathway downstream of distinct activation receptors and constitutes a valuable resource for further elucidating the regulation of NK cell effector responses.

  20. Interaction Between a Novel p21 Activated Kinase (PAK6) and Androgen Receptor in Prostate Cancer

    National Research Council Canada - National Science Library

    Sun, Zijie

    2005-01-01

    The effects of androgens are mediated by the androgen receptor (AR), which plays a critical role in inducing normal differentiation of tissues of the reproductive organs and in the development and progression of prostate cancer...

  1. ING3 promotes prostate cancer growth by activating the androgen receptor.

    Science.gov (United States)

    Nabbi, Arash; McClurg, Urszula L; Thalappilly, Subhash; Almami, Amal; Mobahat, Mahsa; Bismar, Tarek A; Binda, Olivier; Riabowol, Karl T

    2017-05-16

    The androgen receptor (AR) is a major driver of prostate cancer, and increased AR levels and co-activators of the receptor promote the development of prostate cancer. INhibitor of Growth (ING) proteins target lysine acetyltransferase or lysine deacetylase complexes to the histone H3K4Me3 mark of active transcription, to affect chromatin structure and gene expression. ING3 is a stoichiometric member of the TIP60 lysine acetyltransferase complex implicated in prostate cancer development. Biopsies of 265 patients with prostate cancer were stained for ING3, pan-cytokeratin, and DNA. LNCaP and C4-2 androgen-responsive cells were used for in vitro assays including immunoprecipitation, western blotting, Luciferase reporter assay and quantitative polymerase chain reaction. Cell viability and migration assays were performed in prostate cancer cell lines using scrambled siRNA or siRNA targeting ING3. We find that ING3 levels and AR activity positively correlate in prostate cancer. ING3 potentiates androgen effects, increasing expression of androgen-regulated genes and androgen response element-driven reporters to promote growth and anchorage-independent growth. Conversely, ING3 knockdown inhibits prostate cancer cell growth and invasion. ING3 activates the AR by serving as a scaffold to increase interaction between TIP60 and the AR in the cytoplasm, enhancing receptor acetylation and translocation to the nucleus. Activation is independent of ING3's ability to target the TIP60 complex to H3K4Me3, identifying a previously unknown chromatin-independent cytoplasmic activity for ING3. In agreement with in vitro observations, analysis of The Cancer Genome Atlas (TCGA) data (n = 498) and a prostate cancer tissue microarray (n = 256) show that ING3 levels are higher in aggressive prostate cancers, with high levels of ING3 predicting shorter patient survival in a low AR subgroup. Including ING3 levels with currently used indicators such as the Gleason score provides more

  2. Non-neural androgen receptors affect sexual differentiation of brain and behaviour.

    Science.gov (United States)

    Monks, D A; Swift-Gallant, A

    2018-02-01

    Although gonadal testosterone is the principal endocrine factor that promotes masculine traits in mammals, the development of a male phenotype requires local production of both androgenic and oestrogenic signals within target tissues. Much of our knowledge concerning androgenic components of testosterone signalling in sexual differentiation comes from studies of androgen receptor (Ar) loss of function mutants. Here, we review these studies of loss of Ar function and of AR overexpression either globally or selectively in the nervous system of mice. Global and neural mutations affect socio-sexual behaviour and the neuroanatomy of these mice in a sexually differentiated manner. Some masculine traits are affected by both global and neural mutation, indicative of neural mediation, whereas other masculine traits are affected only by global mutation, indicative of an obligatory non-neural androgen target. These results support a model in which multiple sites of androgen action coordinate to produce masculine phenotypes. Furthermore, AR overexpression does not always have a phenotype opposite to that of loss of Ar function mutants, indicative of a nonlinear relationship between androgen dose and masculine phenotype in some cases. Potential mechanisms of Ar gene function in non-neural targets in producing masculine phenotypes are discussed. © 2017 British Society for Neuroendocrinology.

  3. Importance of tyrosine phosphorylation in receptor kinase complexes.

    Science.gov (United States)

    Macho, Alberto P; Lozano-Durán, Rosa; Zipfel, Cyril

    2015-05-01

    Tyrosine phosphorylation is an important post-translational modification that is known to regulate receptor kinase (RK)-mediated signaling in animals. Plant RKs are annotated as serine/threonine kinases, but recent work has revealed that tyrosine phosphorylation is also crucial for the activation of RK-mediated signaling in plants. These initial observations have paved the way for subsequent detailed studies on the mechanism of activation of plant RKs and the biological relevance of tyrosine phosphorylation for plant growth and immunity. In this Opinion article we review recent reports on the contribution of RK tyrosine phosphorylation in plant growth and immunity; we propose that tyrosine phosphorylation plays a major regulatory role in the initiation and transduction of RK-mediated signaling in plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Environmental polycyclic aromatic hydrocarbons affect androgen receptor activation in vitro

    DEFF Research Database (Denmark)

    Vinggaard, Anne Marie; Hnida, Christina; Larsen, John Christian

    2000-01-01

    Nine structurally different polycyclic aromatic hydrocarbons (PAHs) were tested for their ability to either agonize or antagonize the human androgen receptor (hAR) in a sensitive reporter gene assay based on CHO cells transiently cotransfected with a hAR vector and an MMTV-LUC vector. Benz...

  5. Design, synthesis, and biological characterization of metabolically stable selective androgen receptor modulators.

    Science.gov (United States)

    Marhefka, Craig A; Gao, Wenqing; Chung, Kiwon; Kim, Juhyun; He, Yali; Yin, Donghua; Bohl, Casey; Dalton, James T; Miller, Duane D

    2004-02-12

    A series of nonsteroidal ligands were synthesized as second-generation agonists for the androgen receptor (AR). These ligands were designed to eliminate metabolic sites identified in one of our first-generation AR agonists, which was inactive in vivo due to its rapid metabolism to inactive constituents. The binding affinity of these compounds was evaluated using AR isolated from rat ventral prostate. These second-generation compounds bound the AR in a high affinity and stereoselective manner, with K(i) values ranging from about 4 to 130 nM. The ability of these ligands to stimulate AR-mediated transcriptional activation was examined in cells transfected with the human AR and a hormone-dependent luciferase reporter gene. Although some compounds were unable to stimulate AR-mediated transcription, several demonstrated activity similar to that of dihydrotestosterone (DHT, an endogenous steroidal ligand for the AR). We also evaluated the in vivo pharmacologic activity of selected compounds in castrated male rats. Three compounds were identified as selective androgen receptor modulators (SARMs), exhibiting significant anabolic activity while having only moderate to minimal androgenic activity in vivo.

  6. Expression of Progesterone and Androgen Receptors in the Breast of Premenopausal Women, Considering Menstrual Phase.

    Science.gov (United States)

    Fahlén, Mia; Zhang, Hua; Löfgren, Lars; Masironi, Britt; VON Schoultz, Eva; VON Schoultz, B O; Sahlin, Lena

    2018-03-01

    Progesterone and androgens are important for normal development and tumorigenesis of the breast. Breast tissue samples from 49 premenopausal women were obtained. The progesterone receptors (PRA, PRB, PGRMC1 and PGRMC2) and the androgen receptor (AR) were determined in malignant and benign breast tumors and control tissues. The PRB and AR mRNA levels were highest in tumors. PGRMC1 and PGRMC2 mRNA levels were higher in malignant tumors compared to their paired normal tissues. PRA protein showed most immunostaining in benign tumors. PRB immunostaining varied according to menstrual phase. AR immunostaining was highest in the glands of malignant tumors. Progesterone and androgen receptors are differently regulated in tumors compared to normal breast tissues. A malignant breast tumor could appear PR-negative if collected in the luteal phase, but positive in the follicular phase. This finding may have clinical implications. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  7. Distinct Phosphorylation Clusters Determine the Signaling Outcome of Free Fatty Acid Receptor 4/G Protein-Coupled Receptor 120

    DEFF Research Database (Denmark)

    Prihandoko, Rudi; Alvarez-Curto, Elisa; Hudson, Brian D

    2016-01-01

    of these phosphoacceptor sites to alanine completely prevented phosphorylation of mFFA4 but did not limit receptor coupling to extracellular signal regulated protein kinase 1 and 2 (ERK1/2) activation. Rather, an inhibitor of Gq/11proteins completely prevented receptor signaling to ERK1/2. By contrast, the recruitment...... activation. These unique observations define differential effects on signaling mediated by phosphorylation at distinct locations. This hallmark feature supports the possibility that the signaling outcome of mFFA4 activation can be determined by the pattern of phosphorylation (phosphorylation barcode...

  8. The transmembrane domain of the p75 neurotrophin receptor stimulates phosphorylation of the TrkB tyrosine kinase receptor.

    Science.gov (United States)

    Saadipour, Khalil; MacLean, Michael; Pirkle, Sean; Ali, Solav; Lopez-Redondo, Maria-Luisa; Stokes, David L; Chao, Moses V

    2017-10-06

    The function of protein products generated from intramembraneous cleavage by the γ-secretase complex is not well defined. The γ-secretase complex is responsible for the cleavage of several transmembrane proteins, most notably the amyloid precursor protein that results in Aβ, a transmembrane (TM) peptide. Another protein that undergoes very similar γ-secretase cleavage is the p75 neurotrophin receptor. However, the fate of the cleaved p75 TM domain is unknown. p75 neurotrophin receptor is highly expressed during early neuronal development and regulates survival and process formation of neurons. Here, we report that the p75 TM can stimulate the phosphorylation of TrkB (tyrosine kinase receptor B). In vitro phosphorylation experiments indicated that a peptide representing p75 TM increases TrkB phosphorylation in a dose- and time-dependent manner. Moreover, mutagenesis analyses revealed that a valine residue at position 264 in the rat p75 neurotrophin receptor is necessary for the ability of p75 TM to induce TrkB phosphorylation. Because this residue is just before the γ-secretase cleavage site, we then investigated whether the p75(αγ) peptide, which is a product of both α- and γ-cleavage events, could also induce TrkB phosphorylation. Experiments using TM domains from other receptors, EGFR and FGFR1, failed to stimulate TrkB phosphorylation. Co-immunoprecipitation and biochemical fractionation data suggested that p75 TM stimulates TrkB phosphorylation at the cell membrane. Altogether, our results suggest that TrkB activation by p75(αγ) peptide may be enhanced in situations where the levels of the p75 receptor are increased, such as during brain injury, Alzheimer's disease, and epilepsy. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Hemin inhibits internalization of transferrin by reticulocytes and promotes phosphorylation of the membrane transferrin receptor

    International Nuclear Information System (INIS)

    Cox, T.M.; O'Donnell, M.W.; Aisen, P.; London, I.M.

    1985-01-01

    Addition of hemin to reticulocytes inhibits incorporation of iron from transferrin. Heme also regulates protein synthesis in immature erythroid cells through its effects on phosphorylation of the initiation factor eIF-2. The authors have examined its effects on endocytosis of iron-transferrin and phosphorylation of the transferrin receptor. Hemin reduced iron transport but increased cell-associated transferrin. During uptake of 125 I-labeled transferrin in the steady state, the use of a washing technique to dissociate bound transferrin on the cell membrane showed that radioligand accumulated on the surface of hemin-treated cells. Receptor phosphorylation was investigated by immunoprecipitation of reticulocyte extracts after metabolic labeling with [ 32 P]P/sub i/. In the absence of ligand, phosphorylated receptor was chiefly localized on cell stroma. Exposure to transferrin increased cytosolic phosphorylated receptor from 15-30% to approximately 50% of the total, an effect overcome by hemin treatment. The findings suggest a possible relationship of phosphorylation to endocytosis of the transferrin receptor in reticulocytes

  10. Tyrosine Phosphorylation in Toll-Like Receptor Signaling

    Science.gov (United States)

    Chattopadhyay, Saurabh; Sen, Ganes C.

    2014-01-01

    There is a wealth of knowledge about how different Ser/Thr protein kinases participate in Toll-like receptor (TLR) signaling. In many cases, we know the identities of the Ser/Thr residues of various components of the TLR-signaling pathways that are phosphorylated, the functional consequences of the phosphorylation and the responsible protein kinases. In contrast, the analysis of Tyr-phosphorylation of TLRs and their signaling proteins is currently incomplete, because several existing analyses are not systematic or they do not rely on robust experimental data. Nevertheless, it is clear that many TLRs require, for signaling, ligand-dependent phosphorylation of specific Tyr residues in their cytoplasmic domains; the list includes TLR2, TLR3, TLR4, TLR5, TLR8 and TLR9. In this article, we discuss the current status of knowledge on the effect of Tyr-phosphorylation of TLRs and their signaling proteins on their biochemical and biological functions, the possible identities of the relevant protein tyrosine kinases (PTKs) and the nature of regulations of PTK-mediated activation of TLR signaling pathways. PMID:25022196

  11. Novel series of potent, nonsteroidal, selective androgen receptor modulators based on 7H-[1,4]oxazino[3,2-g]quinolin-7-ones.

    Science.gov (United States)

    Higuchi, Robert I; Arienti, Kristen L; López, Francisco J; Mani, Neelakhanda S; Mais, Dale E; Caferro, Thomas R; Long, Yun Oliver; Jones, Todd K; Edwards, James P; Zhi, Lin; Schrader, William T; Negro-Vilar, Andrés; Marschke, Keith B

    2007-05-17

    Recent interest in orally available androgens has fueled the search for new androgens for use in hormone replacement therapy and as anabolic agents. In pursuit of this, we have discovered a series of novel androgen receptor modulators derived from 7H-[1,4]oxazino[3,2-g]quinolin-7-ones. These compounds were synthesized and evaluated in competitive binding assays and an androgen receptor transcriptional activation assay. A number of compounds from the series demonstrated single-digit nanomolar agonist activity in vitro. In addition, lead compound (R)-16e was orally active in established rodent models that measure androgenic and anabolic properties of these agents. In this assay, (R)-16e demonstrated full efficacy in muscle and only partially stimulated the prostate at 100 mg/kg. These data suggest that these compounds may be utilized as selective androgen receptor modulators or SARMs. This series represents a novel class of compounds for use in androgen replacement therapy.

  12. Phospho-kinase profile of triple negative breast cancer and androgen receptor signaling

    International Nuclear Information System (INIS)

    Cuenca-López, María D; Montero, Juan C; Morales, Jorge C; Prat, Aleix; Pandiella, Atanasio; Ocana, Alberto

    2014-01-01

    The androgen receptor (AR) plays a central role in the oncogenesis of different tumors, as is the case in prostate cancer. In triple negative breast cancer (TNBC) a gene expression classification has described different subgroups including a luminal androgen subtype. The AR can be controlled by several mechanisms like the activation of membrane tyrosine kinases and downstream signaling pathways. However little is known in TNBC about how the AR is modulated by these mechanisms and the potential therapeutic strategists to inhibit its expression. We used human samples to evaluate the expression of AR by western-blot and phospho-proteomic kinase arrays that recognize membrane tyrosine kinase receptors and downstream mediators. Western-blots in human cell lines were carried out to analyze the expression and activation of individual proteins. Drugs against these kinases in different conditions were used to measure the expression of the androgen receptor. PCR experiments were performed to assess changes in the AR gene after therapeutic modulation of these pathways. AR is present in a subset of TNBC and its expression correlates with activated membrane receptor kinases-EGFR and PDGFRβ in human samples and cell lines. Inhibition of the PI3K/mTOR pathway in TNBC cell lines decreased notably the expression of the AR. Concomitant administration of the anti-androgen bicalutamide with the EGFR, PDGFRβ and Erk1/2 inhibitors, decreased the amount of AR compared to each agent given alone, and had an additive anti-proliferative effect. Administration of dihydrotestosterone augmented the expression of AR that was not modified by the inhibition of the PI3K/mTOR or Erk1/2 pathways. AR expression was posttranscriptionally regulated by PI3K or Erk1/2 inhibition. Our results describe the expression of the AR in TNBC as a druggable target and further suggest the combination of bicalutamide with inhibitors of EGFR, PDGFRβ or Erk1/2 for future development

  13. Partial androgen insensitivity syndrome due to somatic mosaicism of the androgen receptor.

    Science.gov (United States)

    Batista, Rafael Loch; Rodrigues, Andresa De Santi; Machado, Aline Zamboni; Nishi, Mirian Yumie; Cunha, Flávia Siqueira; Silva, Rosana Barbosa; Costa, Elaine M F; Mendonca, Berenice B; Domenice, Sorahia

    2018-01-26

    Androgen insensitivity syndrome (AIS) is the most frequent etiology of 46,XY disorders of sex development (DSDs), and it is an X-linked disorder caused by mutations in the androgen receptor (AR) gene. AIS patients present a broad phenotypic spectrum and individuals with a partial phenotype present with different degrees of undervirilized external genitalia. There are more than 500 different AR gene allelic variants reported to be linked to AIS, but the presence of somatic mosaicisms has been rarely identified. In the presence of a wild-type AR gene, a significant degree of spontaneous virilization at puberty can be observed, and it could influence the gender assignment, genetic counseling and the clinical and psychological management of these patients and the psychosexual outcomes of these patients are not known. In this study, we report two patients with AR allelic variants in heterozygous (c.382G>T and c.1769-1G>C) causing a partial AIS (PAIS) phenotype. The first patient was raised as female and she had undergone a gonadectomy at puberty. In both patients there was congruency between gender of rearing and gender identity and gender role. Somatic mosaicism is rare in AIS and nonsense AR variant allelic can cause partial AIS phenotype in this situation. Despite the risk of virilization and prenatal androgen exposure, the gender identity and gender role was concordant with sex of rearing in both cases. A better testosterone response can be expected in male individuals and this should be considered in the clinical management.

  14. [7α-18F]fluoro-17α-methyl-5α-dihydrotestosterone: a ligand for androgen receptor-mediated imaging of prostate cancer

    International Nuclear Information System (INIS)

    Garg, Pradeep K.; Labaree, David C.; Hoyte, Robert M.; Hochberg, Richard B.

    2001-01-01

    We have synthesized a 18 F-labeled androgen, [7α- 18 F]fluoro-17α-methyl-5α-dihydrotestosterone, in a no-carrier-added radiosynthesis by exchange of 18 F- (tetrabutylammonium fluoride) with the 7β-tosyloxy of 17α-methyl-5α-dihydrotestosterone. The nonradioactive steroid binds with high affinity and specificity to the androgen receptor and binds poorly, if at all, to other steroid receptors and plasma sex hormone binding globulin. The 7α- 18 F-androgen concentrates markedly in the prostate of rats by an androgen receptor-dependent mechanism. It is likely that [7α- 18 F]fluoro-17α-methyl-5α-dihydrotestosterone will be an excellent positron emission tomography imaging agent for prostate cancer

  15. Potent, nonsteroidal selective androgen receptor modulators (SARMs) based on 8H-[1,4]oxazino[2,3-f]quinolin-8-ones.

    Science.gov (United States)

    Higuchi, Robert I; Thompson, Anthony W; Chen, Jyun-Hung; Caferro, Thomas R; Cummings, Marquis L; Deckhut, Charlotte P; Adams, Mark E; Tegley, Christopher M; Edwards, James P; López, Francisco J; Kallel, E Adam; Karanewsky, Donald S; Schrader, William T; Marschke, Keith B; Zhi, Lin

    2007-10-01

    A series of androgen receptor modulators based on 8H-[1,4]oxazino[2,3-f]quinolin-8-ones was synthesized and evaluated in an androgen receptor transcriptional activation assay. The most potent analogues from the series exhibited single-digit nanomolar potency in vitro. Compound 18h demonstrated full efficacy in the maintenance of muscle weight, at 10 mg/kg, with reduced activity in prostate weight in an in vivo model of androgen action.

  16. Bisphenol A affects androgen receptor function via multiple mechanisms.

    Science.gov (United States)

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

    2013-05-25

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. Published by Elsevier Ireland Ltd.

  17. GABAB receptor phosphorylation regulates KCTD12-induced K+ current desensitization

    DEFF Research Database (Denmark)

    Adelfinger, L; Turecek, R; Ivankova, K

    2014-01-01

    released from the G-protein. Receptor-activated K+ currents desensitize in the sustained presence of agonist to avoid excessive effects on neuronal activity. Desensitization of K+ currents integrates distinct mechanistic underpinnings. GABAB receptor activity reduces protein kinase-A activity, which...... reduces phosphorylation of serine-892 in GABAB2 and promotes receptor degradation. This form of desensitization operates on the time scale of several minutes to hours. A faster form of desensitization is induced by the auxiliary subunit KCTD12, which interferes with channel activation by binding to the G......-protein βγ subunits. Here we show that the two mechanisms of desensitization influence each other. Serine-892 phosphorylation in heterologous cells rearranges KCTD12 at the receptor and slows KCTD12-induced desensitization. Likewise, protein kinase-A activation in hippocampal neurons slows fast...

  18. Identification of androgen receptor antagonists: In vitro investigation and classification methodology for flavonoid.

    Science.gov (United States)

    Wu, Yang; Doering, Jon A; Ma, Zhiyuan; Tang, Song; Liu, Hongling; Zhang, Xiaowei; Wang, Xiaoxiang; Yu, Hongxia

    2016-09-01

    A tremendous gap exists between the number of potential endocrine disrupting chemicals (EDCs) possibly in the environment and the limitation of traditional regulatory testing. In this study, the anti-androgenic potencies of 21 flavonoids were analyzed in vitro, and another 32 flavonoids from the literature were selected as additional chemicals. Molecular dynamic simulations were employed to obtain four different separation approaches based on the different behaviors of ligands and receptors during the process of interaction. Specifically, ligand-receptor complex which highlighted the discriminating features of ligand escape or retention via "mousetrap" mechanism, hydrogen bonds formed during simulation times, ligand stability and the stability of the helix-12 of the receptor were investigated. Together, a methodology was generated that 87.5% of flavonoids could be discriminated as active versus inactive antagonists, and over 90% inactive antagonists could be filtered out before QSAR study. This methodology could be used as a "proof of concept" to identify inactive anti-androgenic flavonoids, as well could be beneficial for rapid risk assessment and regulation of multiple new chemicals for androgenicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Intratumoral conversion of adrenal androgen precursors drives androgen receptor-activated cell growth in prostate cancer more potently than de novo steroidogenesis.

    Science.gov (United States)

    Kumagai, Jinpei; Hofland, Johannes; Erkens-Schulze, Sigrun; Dits, Natasja F J; Steenbergen, Jacobie; Jenster, Guido; Homma, Yukio; de Jong, Frank H; van Weerden, Wytske M

    2013-11-01

    Despite an initial response to hormonal therapy, patients with advanced prostate cancer (PC) almost always progress to castration-resistant disease (CRPC). Although serum testosterone (T) is reduced by androgen deprivation therapy, intratumoral T levels in CRPC are comparable to those in prostate tissue of eugonadal men. These levels could originate from intratumoral conversion of adrenal androgens and/or from de novo steroid synthesis. However, the relative contribution of de novo steroidogenesis to AR-driven cell growth is unknown. The relative contribution of androgen biosynthetic pathways to activate androgen receptor (AR)-regulated cell growth and expression of PSA, FKBP5, and TMPRSS2 was studied at physiologically relevant levels of adrenal androgen precursors and intermediates of de novo androgen biosynthesis in human prostate cancer cell lines, PC346C, VCaP, and LNCaP. In PC346C and VCaP, responses to pregnenolone and progesterone were absent or minimal, while large effects of adrenal androgen precursors were found. VCaP CRPC clones overexpressing CYP17A1 did not acquire an increased ability to use pregnenolone or progesterone to activate AR. In contrast, all precursors stimulated growth and gene expression in LNCaP cells, presumably resulting from the mutated AR in these cells. Our data indicate that at physiological levels of T precursors PC cells can generally convert adrenal androgens, while de novo steroidogenesis is not generally possible in PC cells and is not able to support AR transactivation and PC growth. © 2013 Wiley Periodicals, Inc.

  20. Androgen Receptor Localizes to Plasma Membrane by Binding to Caveolin-1 in Mouse Sertoli Cells

    Directory of Open Access Journals (Sweden)

    Qiong Deng

    2017-01-01

    Full Text Available The nonclassical androgen signaling pathway translates signals into alterations in cellular function within minutes, and this action is proposed to be mediated by an androgen receptor (AR localized to the plasma membrane. This study was designed to determine the mechanism underlying the membrane association of androgen receptor in TM4 cells, a mouse Sertoli cell line. Western blot analysis indicated testosterone-induced AR translocation to the cell membrane. Data from coimmunoprecipitation indicated that AR is associated with caveolin-1, and testosterone enhanced this association. Knockdown of caveolin-1 by shRNA decreased the amount of AR localized to membrane fraction and prevented AR membrane trafficking after being exposed to testosterone at physiological concentration. The palmitoylation inhibitor 2-bromopalmitate decreased AR membrane localization in basal condition and completely blocked testosterone-induced AR translocation to membrane fraction. These data suggested that AR localized to membrane fraction by binding with caveolin-1 through palmitoylation of the cysteine residue. This study provided a new evidence for AR membrane localization and its application for clarifying the nonclassical signaling pathway of androgens.

  1. Multivalent Peptidomimetic Conjugates as Inhibitors of Androgen Receptor Function in Therapy-Resistant Prostate Cancer

    Science.gov (United States)

    2017-10-01

    response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and...hormones that play a critical role in stimulating prostate cancer growth. Androgens activate a protein called the androgen receptor (AR), which...treat patients with prostate cancer, over time the tumors become resistant to the drugs, leaving few treatment options. The goal of this proposal is to

  2. Phorbol ester-induced serine phosphorylation of the insulin receptor decreases its tyrosine kinase activity.

    Science.gov (United States)

    Takayama, S; White, M F; Kahn, C R

    1988-03-05

    The effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the function of the insulin receptor was examined in intact hepatoma cells (Fao) and in solubilized extracts purified by wheat germ agglutinin chromatography. Incubation of ortho[32P]phosphate-labeled Fao cells with TPA increased the phosphorylation of the insulin receptor 2-fold after 30 min. Analysis of tryptic phosphopeptides from the beta-subunit of the receptor by reverse-phase high performance liquid chromatography and determination of their phosphoamino acid composition suggested that TPA predominantly stimulated phosphorylation of serine residues in a single tryptic peptide. Incubation of the Fao cells with insulin (100 nM) for 1 min stimulated 4-fold the phosphorylation of the beta-subunit of the insulin receptor. Prior treatment of the cells with TPA inhibited the insulin-stimulated tyrosine phosphorylation by 50%. The receptors extracted with Triton X-100 from TPA-treated Fao cells and purified on immobilized wheat germ agglutinin retained the alteration in kinase activity and exhibited a 50% decrease in insulin-stimulated tyrosine autophosphorylation and phosphotransferase activity toward exogenous substrates. This was due primarily to a decrease in the Vmax for these reactions. TPA treatment also decreased the Km of the insulin receptor for ATP. Incubation of the insulin receptor purified from TPA-treated cells with alkaline phosphatase decreased the phosphate content of the beta-subunit to the control level and reversed the inhibition, suggesting that the serine phosphorylation of the beta-subunit was responsible for the decreased tyrosine kinase activity. Our results support the notion that the insulin receptor is a substrate for protein kinase C in the Fao cell and that the increase in serine phosphorylation of the beta-subunit of the receptor produced by TPA treatment inhibited tyrosine kinase activity in vivo and in vitro. These data suggest that protein kinase C may regulate the function

  3. The androgen receptor as an emerging target in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Kanda T

    2015-06-01

    Full Text Available Tatsuo Kanda, Osamu Yokosuka Department of Gastroenterology and Nephrology, Chiba University, Graduate School of Medicine, Chiba, Japan Abstract: Hepatocellular carcinoma (HCC is one of the male-dominant liver diseases with poor prognosis, although treatments for HCC have been progressing in the past decades. Androgen receptor (AR is a member of the nuclear receptor superfamily. Previous studies reported that AR was expressed in human HCC and non-HCC tissues. AR is activated both ligand-dependently and ligand-independently. The latter is associated with a mitogen-activated protein kinase–, v-akt murine thymoma viral oncogene homolog 1–, or signal-transducer and activator of transcription–signaling pathway, which has been implicated in the development of HCC. It has been reported that more than 200 RNA expression levels are altered by androgen treatment. In the liver, androgen-responsive genes are cytochrome P450s, transforming growth factor , vascular endothelial growth factor, and glucose-regulated protein 78 kDa, which are also associated with human hepatocarcinogenesis. Recent studies also revealed that AR plays a role in cell migration and metastasis. It is possible that cross-talk among AR-signaling, endoplasmic reticulum stress, and innate immune response is important for human hepatocarcinogenesis and HCC development. This review shows that AR could play a potential role in human HCC and represent one of the important target molecules for the treatment of HCC. Keywords: vascular endothelial growth factor, angiogenesis, glucose-regulated protein 78 kDa, hepatocarcinogenesis, molecular targets 

  4. Disruption of the Interaction of the Androgen Receptor with Chromatin: A Novel Therapeutic Approach in Prostate Cancer

    Science.gov (United States)

    2016-10-01

    AWARD NUMBER: W81XWH-15-1-0543 TITLE: Disruption of the Interaction of the Androgen Receptor with Chromatin : A Novel Therapeutic Approach in...DATES COVERED 8 Sep 2015 - 7 Sep 2016 4. TITLE AND SUBTITLE Disruption of the Interaction of the Androgen Receptor with Chromatin : A Novel 5a. CONTRACT...1: Select and evaluate peptides/peptidomimetics in models of PCa. Aim 2: Determine the molecular action of peptide /peptidomimetics at the chromatin

  5. ARA24/Ran enhances the androgen-dependent NH2- and COOH-terminal interaction of the androgen receptor

    International Nuclear Information System (INIS)

    Harada, Naoki; Ohmori, Yuji; Yamaji, Ryoichi; Higashimura, Yasuki; Okamoto, Kazuki; Isohashi, Fumihide; Nakano, Yoshihisa; Inui, Hiroshi

    2008-01-01

    The androgen receptor (AR) acts as an androgen-dependent transcription factor controlling the development of prostate tissue. Upon binding to androgen, AR undergoes a dynamic structural change leading to interaction between the NH 2 - and COOH-terminal regions of AR (N-C interaction). ARA24/Ran, which is a small GTPase, functions as an AR coactivator. Here, we report that ARA24/Ran enhances the N-C interaction of AR. The constitutively GTP- or GDP-bound form of ARA24/Ran repressed the AR N-C interaction. ARA24/Ran did not enhance the transcriptional activities of AR mutants that disrupt the N-C interaction. ARA24/Ran formed an endogenous protein complex with nuclear AR, but not cytoplasmic AR. Unlike SRC-1 with the positive activity for AR N-C interaction, ARA24/Ran did not enhance the transcriptional activity of the COOH-terminal domain-deleted AR mutant that is constitutively localized in the nucleus. These data demonstrate that ARA24/Ran increases AR transactivation by enhancing the AR N-C interaction in the nucleus

  6. Selective androgen receptor modulators as function promoting therapies.

    Science.gov (United States)

    Bhasin, Shalender; Jasuja, Ravi

    2009-05-01

    The past decade has witnessed an unprecedented discovery effort to develop selective androgen receptor modulators (SARMs) that improve physical function and bone health without adversely affecting the prostate and cardiovascular outcomes. This review describes the historical evolution, the rationale for SARM development, and the mechanisms of testosterone action and SARM selectivity. Although steroidal SARMs have been around since the 1940s, a number of nonsteroidal SARMs that do not serve as substrates for CYP19 aromatase or 5alpha-reductase, act as full agonists in muscle and bone and as partial agonists in prostate are in development. The differing interactions of steroidal and nonsteroidal compounds with androgen receptor (AR) contribute to their unique pharmacologic actions. Ligand binding induces specific conformational changes in the ligand-binding domain, which could modulate surface topology and protein-protein interactions between AR and coregulators, resulting in tissue-specific gene regulation. Preclinical studies have demonstrated the ability of SARMs to increase muscle and bone mass in preclinical rodent models with varying degree of prostate sparing. Phase I trials of SARMs in humans have reported modest increments in fat-free mass. SARMs hold promise as a new class of function promoting anabolic therapies for a number of clinical indications, including functional limitations associated with aging and chronic disease, frailty, cancer cachexia, and osteoporosis.

  7. Update of the androgen receptor gene mutations database.

    Science.gov (United States)

    Gottlieb, B; Beitel, L K; Lumbroso, R; Pinsky, L; Trifiro, M

    1999-01-01

    The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 309 to 374 during the past year. We have expanded the database by adding information on AR-interacting proteins; and we have improved the database by identifying those mutation entries that have been updated. Mutations of unknown significance have now been reported in both the 5' and 3' untranslated regions of the AR gene, and in individuals who are somatic mosaics constitutionally. In addition, single nucleotide polymorphisms, including silent mutations, have been discovered in normal individuals and in individuals with male infertility. A mutation hotspot associated with prostatic cancer has been identified in exon 5. The database is available on the internet (http://www.mcgill.ca/androgendb/), from EMBL-European Bioinformatics Institute (ftp.ebi.ac.uk/pub/databases/androgen), or as a Macintosh FilemakerPro or Word file (MC33@musica.mcgill.ca). Copyright 1999 Wiley-Liss, Inc.

  8. PTTG1, A novel androgen responsive gene is required for androgen-induced prostate cancer cell growth and invasion

    International Nuclear Information System (INIS)

    Zhang, Zheng; Jin, Bo; Jin, Yaqiong; Huang, Shengquan; Niu, Xiaohua; Mao, Zebin; Xin, Dianqi

    2017-01-01

    Androgens (AR) play an important role in initiation and progression of prostate cancer. It has been shown that AR exert their effects mainly through the androgen-activated AR which binds to androgen response elements (AREs) in the regulatory regions of target genes to regulate the transcription of androgen-responsive genes, thus, identification of AR downstream target gene is critical to understand androgen function in prostate cancer. In this study, our results showed that androgen treatment of LNCaP cells induced PTTG1 expression, which was blocked by the androgen receptor antagonist, Casodex. Bioinformatics analysis and experiments using PTTG1 promoter deletion mutants showed that the PTTG1 promoter contains a putative androgen response element (ARE), which localizes in the −851 to −836 region of the promoter. Androgen activated androgen receptor (AR) binding to this ARE was confirmed by Chromatin immunoprecipitation (ChIP) assay. Furthermore, Knockdown of PTTG1 expression using short hairpin RNA significantly reduced androgen-induced LNCaP cell growth and invasion. In addition, we showed PTTG1 is highly expressed in metastasis prostate cancer tissue. These results suggest that PTTG1 is a novel downstream target gene of androgen receptor and take part in prostate cancer proliferation and metastasis. - Highlights: • Androgen treatment of LNCaP cells induced PTTG1 expression. • Knockdown of PTTG1 expression significantly reduced androgen-induced LNCaP cell growth and invasion. • PTTG1 is highly expressed in metastasis prostate cancer tissue. • PTTG1 is a novel downstream target gene of androgen receptor.

  9. CD147 modulates androgen receptor activity through the Akt/Gsk-3β/β-catenin/AR pathway in prostate cancer cells.

    Science.gov (United States)

    Fang, Fang; Qin, Yingxin; Hao, Feng; Li, Qiang; Zhang, Wei; Zhao, Chen; Chen, Shuang; Zhao, Liangzhong; Wang, Liguo; Cai, Jianhui

    2016-08-01

    The androgen signaling pathway serves an important role in the development of prostate cancer. β-Catenin is an androgen receptor (AR) cofactor and augments AR signaling. Glycogen synthase kinase-3β (GSK-3β), a target of phosphorylated serine/threonine protein kinase B (p-Akt), regulates β-catenin stability. In addition, β-catenin, a coregulator of AR, physically interacts with AR and enhances AR-mediated target gene transcription. The multifunctional glycoprotein cluster of differentiation (CD) 147 is highly expressed on the cell surface of the majority of cancer cells, and it promotes tumor invasion, metastasis and growth. In the present study, the molecular effects of CD147 on the Akt/GSK-3β/β-catenin/AR signaling network were investigated in LNCaP cells. Using short hairpin-mediated RNA knockdown of CD147 in LNCaP cells, it was demonstrated that downregulation of CD147 resulted in inhibitory phosphorylation of GSK-3β, and then promoted degeneration of β-catenin and reduced nuclear accumulation of β-catenin. In addition, immunoprecipitation studies demonstrated that CD147 downregulation decreased the formation of a complex between β-catenin and AR. It was shown that CD147 knockdown suppressed the expression of the AR target gene prostate-specific antigen and the growth of AR-positive LNCaP cells. Furthermore, inhibition of PI3K/Akt with LY294002 augmented CD147-mediated function. The present study indicates that the PI3K/Akt pathway may facilitate CD147-mediated activation of the AR pathway.

  10. The study of the androgen receptor profile and changes of level of serum testosterone in human prostatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zhining, Gui; Xiaoke, Hu; Hanping, Lu; Wei, Fan; Naiyun, Wu; Jinhui, Gao [Zhongshan University of Medical Sciences, Guangzhou, GD (China); Hua, Mei; Jinyun, Zeng [First Affiliated Hospital of Zhongshan Univ. of Medical Sciences, Guangzhou, GD (China)

    1993-11-01

    The androgen receptors in biopsy specimens of 22 cases of human prostatic cancer (PC) were studied by radioligand binding assay. The cytoplasmic androgen receptor (AcR) and nuclear androgen receptor (AnR) densities were 305.70 +- 461.68 and 363.04 +- 391.44 pmol/g protein respectively, both were significantly higher than those of 36 benign prostatic hypertrophy (BPH) and 9 normal prostate (NP). Among the prostatic cancers, the AnR/AcR ratios were significantly different between metastatic and primary cancers. This result suggested that there might be migration of AR from nucleus to cytosol in the process of metastasis. The serum testosterone studied by RIA method are significantly lower than that of BPH and NP. Thawmounted autoradiography demonstrated that AR were mainly located in epithelial cells of the glandular tissue of prostate.

  11. Expression of androgen receptor target genes in skeletal muscle

    Directory of Open Access Journals (Sweden)

    Kesha Rana

    2014-10-01

    Full Text Available We aimed to determine the mechanisms of the anabolic actions of androgens in skeletal muscle by investigating potential androgen receptor (AR-regulated genes in in vitro and in vivo models. The expression of the myogenic regulatory factor myogenin was significantly decreased in skeletal muscle from testosterone-treated orchidectomized male mice compared to control orchidectomized males, and was increased in muscle from male AR knockout mice that lacked DNA binding activity (ARΔZF2 versus wildtype mice, demonstrating that myogenin is repressed by the androgen/AR pathway. The ubiquitin ligase Fbxo32 was repressed by 12 h dihydrotestosterone treatment in human skeletal muscle cell myoblasts, and c-Myc expression was decreased in testosterone-treated orchidectomized male muscle compared to control orchidectomized male muscle, and increased in AR∆ZF2 muscle. The expression of a group of genes that regulate the transition from myoblast proliferation to differentiation, Tceal7 , p57 Kip2, Igf2 and calcineurin Aa, was increased in AR∆ZF2 muscle, and the expression of all but p57 Kip2 was also decreased in testosterone-treated orchidectomized male muscle compared to control orchidectomized male muscle. We conclude that in males, androgens act via the AR in part to promote peak muscle mass by maintaining myoblasts in the proliferative state and delaying the transition to differentiation during muscle growth and development, and by suppressing ubiquitin ligase-mediated atrophy pathways to preserve muscle mass in adult muscle.

  12. Coordinate phosphorylation of insulin-receptor kinase and its 175,000-Mr endogenous substrate in rat hepatocytes

    International Nuclear Information System (INIS)

    Okamoto, M.; Karasik, A.; White, M.F.; Kahn, C.R.

    1991-01-01

    To investigate the early events in insulin signal transmission in liver, isolated rat hepatocytes were labeled with 32 P, and proteins phosphorylated in response to insulin were detected by immunoprecipitation with anti-phosphotyrosine and anti-receptor antibodies and analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and autoradiography. In these cells, insulin rapidly stimulated tyrosine phosphorylation of the 95,000-Mr beta-subunit of the insulin receptor and a 175,000-Mr phosphoprotein (pp175). Both proteins were precipitated by anti-phosphotyrosine antibody, whereas only the insulin receptor was recognized with anti-insulin-receptor antibody. In the insulin-stimulated state, both pp175 and the receptor beta-subunit were found to be phosphorylated on tyrosine and serine residues. Based on precipitation by the two antibodies, receptor phosphorylation was biphasic with an initial increase in tyrosine phosphorylation followed by a more gradual increase in serine phosphorylation over the first 30 min of stimulation. The time course of phosphorylation of pp175 was rapid and paralleled that of the beta-subunit of the insulin receptor. The pp175 was clearly distinguished from the insulin receptor, because it was detected only when boiling SDS was used to extract cellular phosphoproteins, whereas the insulin receptor was extracted with either Triton X-100 or SDS. In addition, the tryptic peptide maps of the two proteins were distinct. The dose-response curve for insulin stimulation was shifted slightly to the left of the insulin receptor, suggesting some signal amplification at this step. These data suggest that pp175 is a major endogenous substrate of the insulin receptor in liver and may be a cytoskeletal-associated protein

  13. Phosphorylation of G Protein-Coupled Receptors: From the Barcode Hypothesis to the Flute Model.

    Science.gov (United States)

    Yang, Zhao; Yang, Fan; Zhang, Daolai; Liu, Zhixin; Lin, Amy; Liu, Chuan; Xiao, Peng; Yu, Xiao; Sun, Jin-Peng

    2017-09-01

    Seven transmembrane G protein-coupled receptors (GPCRs) are often phosphorylated at the C terminus and on intracellular loops in response to various extracellular stimuli. Phosphorylation of GPCRs by GPCR kinases and certain other kinases can promote the recruitment of arrestin molecules. The arrestins critically regulate GPCR functions not only by mediating receptor desensitization and internalization, but also by redirecting signaling to G protein-independent pathways via interactions with numerous downstream effector molecules. Accumulating evidence over the past decade has given rise to the phospho-barcode hypothesis, which states that ligand-specific phosphorylation patterns of a receptor direct its distinct functional outcomes. Our recent work using unnatural amino acid incorporation and fluorine-19 nuclear magnetic resonance ( 19 F-NMR) spectroscopy led to the flute model, which provides preliminary insight into the receptor phospho-coding mechanism, by which receptor phosphorylation patterns are recognized by an array of phosphate-binding pockets on arrestin and are translated into distinct conformations. These selective conformations are recognized by various effector molecules downstream of arrestin. The phospho-barcoding mechanism enables arrestin to recognize a wide range of phosphorylation patterns of GPCRs, contributing to their diverse functions. Copyright © 2017 by The Author(s).

  14. Androgen Receptor: A Complex Therapeutic Target for Breast Cancer

    Science.gov (United States)

    Narayanan, Ramesh; Dalton, James T.

    2016-01-01

    Molecular and histopathological profiling have classified breast cancer into multiple sub-types empowering precision treatment. Although estrogen receptor (ER) and human epidermal growth factor receptor (HER2) are the mainstay therapeutic targets in breast cancer, the androgen receptor (AR) is evolving as a molecular target for cancers that have developed resistance to conventional treatments. The high expression of AR in breast cancer and recent discovery and development of new nonsteroidal drugs targeting the AR provide a strong rationale for exploring it again as a therapeutic target in this disease. Ironically, both nonsteroidal agonists and antagonists for the AR are undergoing clinical trials, making AR a complicated target to understand in breast cancer. This review provides a detailed account of AR’s therapeutic role in breast cancer. PMID:27918430

  15. Androgen Receptor: A Complex Therapeutic Target for Breast Cancer

    Directory of Open Access Journals (Sweden)

    Ramesh Narayanan

    2016-12-01

    Full Text Available Molecular and histopathological profiling have classified breast cancer into multiple sub-types empowering precision treatment. Although estrogen receptor (ER and human epidermal growth factor receptor (HER2 are the mainstay therapeutic targets in breast cancer, the androgen receptor (AR is evolving as a molecular target for cancers that have developed resistance to conventional treatments. The high expression of AR in breast cancer and recent discovery and development of new nonsteroidal drugs targeting the AR provide a strong rationale for exploring it again as a therapeutic target in this disease. Ironically, both nonsteroidal agonists and antagonists for the AR are undergoing clinical trials, making AR a complicated target to understand in breast cancer. This review provides a detailed account of AR’s therapeutic role in breast cancer.

  16. Molecular basis of androgen insensitivity

    NARCIS (Netherlands)

    Brinkmann, A.; Jenster, G.; Ris-Stalpers, C.; van der Korput, H.; Brüggenwirth, H.; Boehmer, A.; Trapman, J.

    1996-01-01

    Male sexual differentiation and development proceed under direct control of androgens. Androgen action is mediated by the intracellular androgen receptor, which belongs to the superfamily of ligand-dependent transcription factors. In the X-linked androgen insensitivity syndrome, defects in the

  17. Enzalutamide inhibits androgen receptor-positive bladder cancer cell growth.

    Science.gov (United States)

    Kawahara, Takashi; Ide, Hiroki; Kashiwagi, Eiji; El-Shishtawy, Kareem A; Li, Yi; Reis, Leonardo O; Zheng, Yichun; Miyamoto, Hiroshi

    2016-10-01

    Emerging preclinical evidence suggests that androgen-mediated androgen receptor (AR) signals promote bladder cancer progression. However, little is known about the efficacy of an AR signaling inhibitor, enzalutamide, in the growth of bladder cancer cells. In this study, we compared the effects of enzalutamide and 2 other classic antiandrogens, flutamide and bicalutamide, on androgen-induced bladder cancer cell proliferation, migration, and invasion as well as tumor growth in vivo. Thiazolyl blue cell viability assay, flow cytometry, scratch wound-healing assay, transwell invasion assay, real-time polymerase chain reaction, and reporter gene assay were performed in AR-positive (e.g., UMUC3, TCCSUP, and 647V-AR) and AR-negative (e.g., UMUC3-AR-short hairpin RNA [shRNA], TCCSUP-AR-shRNA, 647V) bladder cancer lines treated with dihydrotestosterone and each AR antagonist. We also used a mouse xenograft model for bladder cancer. Dihydrotestosterone increased bladder cancer cell proliferation, migration, and invasion indicating that endogenous or exogenous AR was functional. Enzalutamide, hydroxyflutamide, and bicalutamide showed similar inhibitory effects, without significant agonist activity, on androgen-mediated cell viability/apoptosis, cell migration, and cell invasion in AR-positive lines. No significant effects of dihydrotestosterone as well as AR antagonists on the growth of AR-negative cells were seen. Correspondingly, in UMUC3 cells, these AR antagonists down-regulated androgen-induced expression of AR, matrix metalloproteinase-2, and interleukin-6. Androgen-enhanced AR-mediated transcriptional activity was also blocked by each AR antagonist exhibiting insignificant agonist activity. In UMUC3 xenograft-bearing mice, oral gavage treatment with each antiandrogen retarded tumor growth, and only enzalutamide demonstrated a statistically significant suppression compared with mock treatment. Our current data support recent observations indicating the involvement of

  18. Androgen Receptor Expression in Thai Breast Cancer Patients

    Directory of Open Access Journals (Sweden)

    Suthat Chottanapund

    2016-09-01

    Full Text Available The aim of this study was to investigate prevalence and related factors of androgen receptor (AR expression in Thai breast cancer patients. A descriptive study was done in 95 patients, who were admitted to Charoenkrung Pracharak Hospital, Bangkok (2011–2013. Statistical relationships were examined between AR protein expression, tumor status, and patient characteristics. Compared with those from Western countries, ethnic Thai patients were younger at age of diagnosis and had a higher proliferative index (high Ki-67 expression, which indicates unfavorable prognosis. In addition, 91% of the Thai breast tumors that were positive for any of the following receptors, estrogen receptor (ER, progesterone receptor (PR, and human epidermal growth factor receptor 2 (HER2 also expressed the AR protein, while in triple negative breast tumors only 33% were AR positive. ER and PR expression was positively related with AR expression, while AR expression was inversely correlated to Ki-67 expression. AR status was strongly correlated with ER and PR status in Thai patients. There is an inverse relationship between Ki-67 and AR, which suggests that AR may be a prognostic factor for breast cancer.

  19. Metabolomics for informing adverse outcome pathways: Androgen receptor activation and the pharmaceutical spironolactone

    International Nuclear Information System (INIS)

    Davis, J.M.; Ekman, D.R.; Skelton, D.M.; LaLone, C.A.; Ankley, G.T.; Cavallin, J.E.; Villeneuve, D.L.; Collette, T.W.

    2017-01-01

    Highlights: • Metabolomics identified potential key events in an androgen receptor activation AOP. • Metabolomics indicate spironolactone may elicit effects via multiple nuclear receptors. • Spironolactone exposure may elicit interactive effects in multi-stressor environments. - Abstract: One objective in developing adverse outcome pathways (AOPs) is to connect biological changes that are relevant to risk assessors (i.e., fecundity) to molecular and cellular-level alterations that might be detectable at earlier stages of a chemical exposure. Here, we examined biochemical responses of fathead minnows (Pimephales promelas) to inform an AOP relevant to spironolactone’s activation of the androgen receptor, as well as explore other biological impacts possibly unrelated to this receptor. Liquid chromatography with high resolution mass spectrometry (LC–MS) was used to measure changes in endogenous polar metabolites in livers of male and female fish that were exposed to five water concentrations of spironolactone (0, 0.05, 0.5, 5, or 50 μg L"−"1) for 21 days. Metabolite profiles were affected at the two highest concentrations (5 and 50 μg L"−"1), but not in the lower-level exposures, which agreed with earlier reported results of reduced female fecundity and plasma vitellogenin (VTG) levels. We then applied partial least squares regression to assess whether metabolite alterations covaried with changes in fecundity, VTG gene expression and protein concentrations, and plasma 17β-estradiol and testosterone concentrations. Metabolite profiles significantly covaried with all measured endpoints in females, but only with plasma testosterone in males. Fecundity reductions occurred in parallel with changes in metabolites important in osmoregulation (e.g., betaine), membrane transport (e.g., L-carnitine), and biosynthesis of carnitine (e.g., methionine) and VTG (e.g., glutamate). Based on a network analysis program (i.e., mummichog), spironolactone also affected

  20. Metabolomics for informing adverse outcome pathways: Androgen receptor activation and the pharmaceutical spironolactone

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J.M., E-mail: davis.john@epa.gov [U.S. EPA, National Exposure Research Laboratory, 960 College Station Rd., Athens, GA 30605 (United States); Ekman, D.R., E-mail: ekman.drew@epa.gov [U.S. EPA, National Exposure Research Laboratory, 960 College Station Rd., Athens, GA 30605 (United States); Skelton, D.M. [U.S. EPA, National Exposure Research Laboratory, 960 College Station Rd., Athens, GA 30605 (United States); LaLone, C.A.; Ankley, G.T.; Cavallin, J.E.; Villeneuve, D.L. [U.S. EPA, National Health and Environmental Effects Research Laboratory, 6201 Congdon Blvd., Duluth, MN 55804 (United States); Collette, T.W. [U.S. EPA, National Exposure Research Laboratory, 960 College Station Rd., Athens, GA 30605 (United States)

    2017-03-15

    Highlights: • Metabolomics identified potential key events in an androgen receptor activation AOP. • Metabolomics indicate spironolactone may elicit effects via multiple nuclear receptors. • Spironolactone exposure may elicit interactive effects in multi-stressor environments. - Abstract: One objective in developing adverse outcome pathways (AOPs) is to connect biological changes that are relevant to risk assessors (i.e., fecundity) to molecular and cellular-level alterations that might be detectable at earlier stages of a chemical exposure. Here, we examined biochemical responses of fathead minnows (Pimephales promelas) to inform an AOP relevant to spironolactone’s activation of the androgen receptor, as well as explore other biological impacts possibly unrelated to this receptor. Liquid chromatography with high resolution mass spectrometry (LC–MS) was used to measure changes in endogenous polar metabolites in livers of male and female fish that were exposed to five water concentrations of spironolactone (0, 0.05, 0.5, 5, or 50 μg L{sup −1}) for 21 days. Metabolite profiles were affected at the two highest concentrations (5 and 50 μg L{sup −1}), but not in the lower-level exposures, which agreed with earlier reported results of reduced female fecundity and plasma vitellogenin (VTG) levels. We then applied partial least squares regression to assess whether metabolite alterations covaried with changes in fecundity, VTG gene expression and protein concentrations, and plasma 17β-estradiol and testosterone concentrations. Metabolite profiles significantly covaried with all measured endpoints in females, but only with plasma testosterone in males. Fecundity reductions occurred in parallel with changes in metabolites important in osmoregulation (e.g., betaine), membrane transport (e.g., L-carnitine), and biosynthesis of carnitine (e.g., methionine) and VTG (e.g., glutamate). Based on a network analysis program (i.e., mummichog), spironolactone also

  1. An examination of the characteristics, concentration, and distribution of androgen receptor in rat testis during sexual maturation

    International Nuclear Information System (INIS)

    Buzek, S.W.

    1989-01-01

    In these studies a nuclear exchange assay was established in rat testis in which exchange after 86 hours at 4 degree C was greater than 85% complete and receptor was stable. Receptor concentration per DNA measured by exchange declined between 15 and 25 days of age in the rat testis, then increased 4-fold during sexual maturation. Proliferation of germ cells which had low receptor concentration appeared to account for the early decline in testicular receptor concentration, whereas increase in receptor number per Sertoli cell between 25 and 35 days of age contributed to the later increase. Detailed studies showed that other possible explanations for changes in receptor number were not likely. Androgen receptor dynamics in testicular cells showed rapid, specific uptake of [ 3 H]-testosterone that was easily blocked by unlabeled testosterone, and medroxyprogesterone acetate, but not as well as by the anti-androgens cyproterone acetate and hydroxyflutamide

  2. The Role of Stat3 Activation in Androgen Receptor Signaling and Prostate Cancer

    National Research Council Canada - National Science Library

    Gao, Allen C

    2006-01-01

    .... The experiments proposed in this application are based upon the hypothesis that Stat3 activation alters androgen receptor signaling pathways which in turn results in the loss of growth control in prostate cancer cells...

  3. The Role of Stat3 Activation in Androgen Receptor Signaling and Prostate Cancer

    National Research Council Canada - National Science Library

    Gao, Allen

    2004-01-01

    .... The experiments proposed in this application are based upon the hypothesis that stat3 activation alters androgen receptor signaling pathways, that in turn results in the loss of growth control in prostate cancer cells...

  4. The Role of Stat3 Activation in Androgen Receptor Signaling and Prostate Cancer

    National Research Council Canada - National Science Library

    Gao, Allen

    2002-01-01

    .... The experiments proposed in this application are based upon the hypothesis that Stat3 activation alters androgen receptor signaling pathways, that in turn results in the loss of growth control in prostate cancer cells...

  5. The Role of Stat3 Activation in Androgen Receptor Signaling and Prostate Cancer

    National Research Council Canada - National Science Library

    Gao, Allen C

    2005-01-01

    .... The experiments proposed in this application are based upon the hypothesis that Stat3 activation alters androgen receptor signaling pathways, that in turn results in the loss of growth control in prostate cancer cells...

  6. The Role of Stat3 Activation in Androgen Receptor Signaling and Prostate Cancer

    National Research Council Canada - National Science Library

    Gao, Allen

    2003-01-01

    .... The experiments proposed in this application are based upon the hypothesis that Stat3 activation alters androgen receptor signaling pathways, that in turn results in the loss of growth control in prostate cancer cells...

  7. A Time-course Study with the Androgen Receptor Antagonist Flutamide in Fish

    Science.gov (United States)

    Flutamide, a drug registered to treat some types of prostate cancer in humans, has been used for many years as a model androgen receptor (AR) antagonist in studies aimed at characterizing disruption of the vertebrate hypothalamic-pituitary-gonadal (HPG) axis. Various studies hav...

  8. LncRNA HOTAIR Enhances the Androgen-Receptor-Mediated Transcriptional Program and Drives Castration-Resistant Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Ali Zhang

    2015-10-01

    Full Text Available Understanding the mechanisms of androgen receptor (AR activation in the milieu of low androgen is critical to effective treatment of castration-resistant prostate cancer (CRPC. Here, we report HOTAIR as an androgen-repressed lncRNA, and, as such, it is markedly upregulated following androgen deprivation therapies and in CRPC. We further demonstrate a distinct mode of lncRNA-mediated gene regulation, wherein HOTAIR binds to the AR protein to block its interaction with the E3 ubiquitin ligase MDM2, thereby preventing AR ubiquitination and protein degradation. Consequently, HOTAIR expression is sufficient to induce androgen-independent AR activation and drive the AR-mediated transcriptional program in the absence of androgen. Functionally, HOTAIR overexpression increases, whereas HOTAIR knockdown decreases, prostate cancer cell growth and invasion. Taken together, our results provide compelling evidence of lncRNAs as drivers of androgen-independent AR activity and CRPC progression, and they support the potential of lncRNAs as therapeutic targets.

  9. Coarse-grained molecular simulation of epidermal growth factor receptor protein tyrosine kinase multi-site self-phosphorylation.

    Directory of Open Access Journals (Sweden)

    John G Koland

    2014-01-01

    Full Text Available Upon the ligand-dependent dimerization of the epidermal growth factor receptor (EGFR, the intrinsic protein tyrosine kinase (PTK activity of one receptor monomer is activated, and the dimeric receptor undergoes self-phosphorylation at any of eight candidate phosphorylation sites (P-sites in either of the two C-terminal (CT domains. While the structures of the extracellular ligand binding and intracellular PTK domains are known, that of the ∼225-amino acid CT domain is not, presumably because it is disordered. Receptor phosphorylation on CT domain P-sites is critical in signaling because of the binding of specific signaling effector molecules to individual phosphorylated P-sites. To investigate how the combination of conventional substrate recognition and the unique topological factors involved in the CT domain self-phosphorylation reaction lead to selectivity in P-site phosphorylation, we performed coarse-grained molecular simulations of the P-site/catalytic site binding reactions that precede EGFR self-phosphorylation events. Our results indicate that self-phosphorylation of the dimeric EGFR, although generally believed to occur in trans, may well occur with a similar efficiency in cis, with the P-sites of both receptor monomers being phosphorylated to a similar extent. An exception was the case of the most kinase-proximal P-site-992, the catalytic site binding of which occurred exclusively in cis via an intramolecular reaction. We discovered that the in cis interaction of P-site-992 with the catalytic site was facilitated by a cleft between the N-terminal and C-terminal lobes of the PTK domain that allows the short CT domain sequence tethering P-site-992 to the PTK core to reach the catalytic site. Our work provides several new mechanistic insights into the EGFR self-phosphorylation reaction, and demonstrates the potential of coarse-grained molecular simulation approaches for investigating the complexities of self-phosphorylation in

  10. Androgen Receptor Involvement in Rat Amelogenesis: An Additional Way for Endocrine-Disrupting Chemicals to Affect Enamel Synthesis.

    Science.gov (United States)

    Jedeon, Katia; Loiodice, Sophia; Salhi, Khaled; Le Normand, Manon; Houari, Sophia; Chaloyard, Jessica; Berdal, Ariane; Babajko, Sylvie

    2016-11-01

    Endocrine-disrupting chemicals (EDCs) that interfere with the steroid axis can affect amelogenesis, leading to enamel hypomineralization similar to that of molar incisor hypomineralization, a recently described enamel disease. We investigated the sex steroid receptors that may mediate the effects of EDCs during rat amelogenesis. The expression of androgen receptor (AR), estrogen receptor (ER)-α, and progesterone receptor was dependent on the stage of ameloblast differentiation, whereas ERβ remained undetectable. AR was the only receptor selectively expressed in ameloblasts involved in final enamel mineralization. AR nuclear translocation and induction of androgen-responsive element-containing promoter activity upon T treatment, demonstrated ameloblast responsiveness to androgens. T regulated the expression of genes involved in enamel mineralization such as KLK4, amelotin, SLC26A4, and SLC5A8 but not the expression of genes encoding matrix proteins, which determine enamel thickness. Vinclozolin and to a lesser extent bisphenol A, two antiandrogenic EDCs that cause enamel defects, counteracted the actions of T. In conclusion, we show, for the first time, the following: 1) ameloblasts express AR; 2) the androgen signaling pathway is involved in the enamel mineralization process; and 3) EDCs with antiandrogenic effects inhibit AR activity and preferentially affect amelogenesis in male rats. Their action, through the AR pathway, may specifically and irreversibly affect enamel, potentially leading to the use of dental defects as a biomarker of exposure to environmental pollutants. These results are consistent with the steroid hormones affecting ameloblasts, raising the issue of the hormonal influence on amelogenesis and possible sexual dimorphism in enamel quality.

  11. GLI1, a crucial mediator of sonic hedgehog signaling in prostate cancer, functions as a negative modulator for androgen receptor

    International Nuclear Information System (INIS)

    Chen, Guangchun; Goto, Yutaka; Sakamoto, Ryuichi; Tanaka, Kimitaka; Matsubara, Eri; Nakamura, Masafumi; Zheng, Hong; Lu, Jian; Takayanagi, Ryoichi; Nomura, Masatoshi

    2011-01-01

    Research highlights: → GLI1, which play a central role in sonic hedgehog signaling in prostate cancer, can act as a co-repressor to substantially block androgen receptor-mediated transactivation. → GLI1 directly interacts with AR. → SHH-GLI pathway might be one of determinants governing the transition of prostate cancer from an androgen-dependent to an androgen-independent state. -- Abstract: Sonic hedgehog (SHH) signaling, acting in a combinatorial manner with androgen signaling, is essential for prostate patterning and development. Recently, elevated activation of SHH signaling has been shown to play important roles in proliferation, progression and metastasis of prostate cancer. In this report, we demonstrate for the first time, that GLI1, which has been shown to play a central role in SHH signaling in prostate cancer, can act as a co-repressor to substantially block androgen receptor (AR)-mediated transactivation, at least in part, by directly interacting with AR. Our observations suggest that the SHH-GLI pathway might be one of determinants governing the transition of prostate cancer from an androgen-dependent to an androgen-independent state by compensating, or even superseding androgen signaling.

  12. A novel selective androgen receptor modulator (SARM) MK-4541 exerts anti-androgenic activity in the prostate cancer xenograft R-3327G and anabolic activity on skeletal muscle mass & function in castrated mice.

    Science.gov (United States)

    Chisamore, Michael J; Gentile, Michael A; Dillon, Gregory Michael; Baran, Matthew; Gambone, Carlo; Riley, Sean; Schmidt, Azriel; Flores, Osvaldo; Wilkinson, Hilary; Alves, Stephen E

    2016-10-01

    The androgen receptor (AR) is a member of the nuclear hormone receptor super family of transcription factors. Androgens play an essential role in the development, growth, and maintenance of male sex organs, as well as the musculoskeletal and central nervous systems. Yet with advancing age, androgens can drive the onset of prostate cancer, the second leading cause of cancer death in males within the United States. Androgen deprivation therapy (ADT) by pharmacologic and/or surgical castration induces apoptosis of prostate cells and subsequent shrinkage of the prostate and prostate tumors. However, ADT is associated with significant musculoskeletal and behavioral adverse effects. The unique pharmacological activity of selective androgen receptor modulator (SARM) MK-4541 recently has been reported as an AR antagonist with 5α-reductase inhibitor function. The molecule inhibits proliferation and induces apoptosis in AR positive, androgen dependent prostate cancer cells. Importantly, MK-4541 inhibited androgen-dependent prostate growth in male rats yet maintained lean body mass and bone formation following ovariectomy in female rats. In the present study, we evaluated the effects of SARM MK-4541 in the androgen-dependent Dunning R3327-G prostate carcinoma xenograft mouse model as well as on skeletal muscle mass and function, and AR-regulated behavior in mice. MK-4541 significantly inhibited the growth of R3327-G prostate tumors, exhibited anti-androgen effects on the seminal vesicles, reduced plasma testosterone concentrations in intact males, and inhibited Ki67 expression. MK-4541 treated xenografts appeared similar to xenografts in castrated mice. Importantly, we demonstrate that MK-4541 exhibited anabolic activity in androgen deficient conditions, increasing lean body mass and muscle function in adult castrated mice. Moreover, MK-4541 treatment restored general activity levels in castrated mice. Thus, MK-4541 exhibits an optimum profile as an adjuvant therapy to ADT

  13. Phosphorylation inhibits DNA-binding of alternatively spliced aryl hydrocarbon receptor nuclear translocator

    International Nuclear Information System (INIS)

    Kewley, Robyn J.; Whitelaw, Murray L.

    2005-01-01

    The basic helix-loop-helix/PER-ARNT-SIM homology (bHLH/PAS) transcription factor ARNT (aryl hydrocarbon receptor nuclear translocator) is a key component of various pathways which induce the transcription of cytochrome P450 and hypoxia response genes. ARNT can be alternatively spliced to express Alt ARNT, containing an additional 15 amino acids immediately N-terminal to the DNA-binding basic region. Here, we show that ARNT and Alt ARNT proteins are differentially phosphorylated by protein kinase CKII in vitro. Phosphorylation had an inhibitory effect on DNA-binding to an E-box probe by Alt ARNT, but not ARNT, homodimers. This inhibitory phosphorylation occurs through Ser77. Moreover, a point mutant, Alt ARNT S77A, shows increased activity on an E-box reporter gene, consistent with Ser77 being a regulatory site in vivo. In contrast, DNA binding by an Alt ARNT/dioxin receptor heterodimer to the xenobiotic response element is not inhibited by phosphorylation with CKII, nor does Alt ARNT S77A behave differently from wild type Alt ARNT in the context of a dioxin receptor heterodimer

  14. Structural analysis of complementary DNA and amino acid sequences of human and rat androgen receptors

    International Nuclear Information System (INIS)

    Chang, C.; Kokontis, J.; Liao, S.

    1988-01-01

    Structural analysis of cDNAs for human and rat androgen receptors (ARs) indicates that the amino-terminal regions of ARs are rich in oligo- and poly(amino acid) motifs as in some homeotic genes. The human AR has a long stretch of repeated glycines, whereas rat AR has a long stretch of glutamines. There is a considerable sequence similarity among ARs and the receptors for glucocorticoids, progestins, and mineralocorticoids within the steroid-binding domains. The cysteine-rich DNA-binding domains are well conserved. Translation of mRNA transcribed from AR cDNAs yielded 94- and 76-kDa proteins and smaller forms that bind to DNA and have high affinity toward androgens. These rat or human ARs were recognized by human autoantibodies to natural Ars. Molecular hybridization studies, using AR cDNAs as probes, indicated that the ventral prostate and other male accessory organs are rich in AR mRNA and that the production of AR mRNA in the target organs may be autoregulated by androgens

  15. 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.

  16. Enhanced Prediction of Src Homology 2 (SH2) Domain Binding Potentials Using a Fluorescence Polarization-derived c-Met, c-Kit, ErbB, and Androgen Receptor Interactome*

    Science.gov (United States)

    Leung, Kin K.; Hause, Ronald J.; Barkinge, John L.; Ciaccio, Mark F.; Chuu, Chih-Pin; Jones, Richard B.

    2014-01-01

    Many human diseases are associated with aberrant regulation of phosphoprotein signaling networks. Src homology 2 (SH2) domains represent the major class of protein domains in metazoans that interact with proteins phosphorylated on the amino acid residue tyrosine. Although current SH2 domain prediction algorithms perform well at predicting the sequences of phosphorylated peptides that are likely to result in the highest possible interaction affinity in the context of random peptide library screens, these algorithms do poorly at predicting the interaction potential of SH2 domains with physiologically derived protein sequences. We employed a high throughput interaction assay system to empirically determine the affinity between 93 human SH2 domains and phosphopeptides abstracted from several receptor tyrosine kinases and signaling proteins. The resulting interaction experiments revealed over 1000 novel peptide-protein interactions and provided a glimpse into the common and specific interaction potentials of c-Met, c-Kit, GAB1, and the human androgen receptor. We used these data to build a permutation-based logistic regression classifier that performed considerably better than existing algorithms for predicting the interaction potential of several SH2 domains. PMID:24728074

  17. Prostate Cancer Cells Express More Androgen Receptor (AR) Following Androgen Deprivation, Improving Recognition by AR-Specific T Cells.

    Science.gov (United States)

    Olson, Brian M; Gamat, Melissa; Seliski, Joseph; Sawicki, Thomas; Jeffery, Justin; Ellis, Leigh; Drake, Charles G; Weichert, Jamey; McNeel, Douglas G

    2017-12-01

    Androgen deprivation is the primary therapy for recurrent prostate cancer, and agents targeting the androgen receptor (AR) pathway continue to be developed. Because androgen-deprivation therapy (ADT) has immmunostimulatory effects as well as direct antitumor effects, AR-targeted therapies have been combined with other anticancer therapies, including immunotherapies. Here, we sought to study whether an antigen-specific mechanism of resistance to ADT (overexpression of the AR) may result in enhanced AR-specific T-cell immune recognition, and whether this might be strategically combined with an antitumor vaccine targeting the AR. Androgen deprivation increased AR expression in human and murine prostate tumor cells in vitro and in vivo The increased expression persisted over time. Increased AR expression was associated with recognition and cytolytic activity by AR-specific T cells. Furthermore, ADT combined with vaccination, specifically a DNA vaccine encoding the ligand-binding domain of the AR, led to improved antitumor responses as measured by tumor volumes and delays in the emergence of castrate-resistant prostate tumors in two murine prostate cancer models (Myc-CaP and prostate-specific PTEN-deficient mice). Together, these data suggest that ADT combined with AR-directed immunotherapy targets a major mechanism of resistance, overexpression of the AR. This combination may be more effective than ADT combined with other immunotherapeutic approaches. Cancer Immunol Res; 5(12); 1074-85. ©2017 AACR . ©2017 American Association for Cancer Research.

  18. 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...

  19. Bone stroma-derived cells change coregulators recruitment to androgen receptor and decrease cell proliferation in androgen-sensitive and castration-resistant prostate cancer cells

    International Nuclear Information System (INIS)

    Villagran, Marcelo A.; Gutierrez-Castro, Francisco A.; Pantoja, Diego F.; Alarcon, Jose C.; Fariña, Macarena A.; Amigo, Romina F.; Muñoz-Godoy, Natalia A.; Pinilla, Mabel G.; Peña, Eduardo A.; Gonzalez-Chavarria, Ivan; Toledo, Jorge R.; Rivas, Coralia I.; Vera, Juan C.; McNerney, Eileen M.; Onate, Sergio A.

    2015-01-01

    Prostate cancer (CaP) bone metastasis is an early event that remains inactive until later-stage progression. Reduced levels of circulating androgens, due to andropause or androgen deprivation therapies, alter androgen receptor (AR) coactivator expression. Coactivators shift the balance towards enhanced AR-mediated gene transcription that promotes progression to androgen-resistance. Disruptions in coregulators may represent a molecular switch that reactivates latent bone metastasis. Changes in AR-mediated transcription in androgen-sensitive LNCaP and androgen-resistant C4-2 cells were analyzed for AR coregulator recruitment in co-culture with Saos-2 and THP-1. The Saos-2 cell line derived from human osteosarcoma and THP-1 cell line representing human monocytes were used to display osteoblast and osteoclast activity. Increased AR activity in androgen-resistant C4-2 was due to increased AR expression and SRC1/TIF2 recruitment and decreased SMRT/NCoR expression. AR activity in both cell types was decreased over 90% when co-cultured with Saos-2 or THP-1 due to dissociation of AR from the SRC1/TIF2 and SMRT/NCoR coregulators complex, in a ligand-dependent and cell-type specific manner. In the absence of androgens, Saos-2 decreased while THP-1 increased proliferation of LNCaP cells. In contrast, both Saos-2 and THP-1 decreased proliferation of C4-2 in absence and presence of androgens. Global changes in gene expression from both CaP cell lines identified potential cell cycle and androgen regulated genes as mechanisms for changes in cell proliferation and AR-mediated transactivation in the context of bone marrow stroma cells. - Highlights: • Decreased corepressor expression change AR in androgen-resistance prostate cancer. • Bone stroma-derived cells change AR coregulator recruitment in prostate cancer. • Bone stroma cells change cell proliferation in androgen-resistant cancer cells. • Global gene expression in CaP cells is modified by bone stroma cells in co

  20. Bone stroma-derived cells change coregulators recruitment to androgen receptor and decrease cell proliferation in androgen-sensitive and castration-resistant prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Villagran, Marcelo A.; Gutierrez-Castro, Francisco A.; Pantoja, Diego F.; Alarcon, Jose C.; Fariña, Macarena A.; Amigo, Romina F.; Muñoz-Godoy, Natalia A. [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Pinilla, Mabel G. [Department of Medical Specialties, School of Medicine, University of Concepcion, Concepcion (Chile); Peña, Eduardo A.; Gonzalez-Chavarria, Ivan; Toledo, Jorge R.; Rivas, Coralia I.; Vera, Juan C. [Department of Physiopathology, School of Biological Sciences, University of Concepcion, Concepcion (Chile); McNerney, Eileen M. [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Onate, Sergio A., E-mail: sergio.onate@udec.cl [Molecular Endocrinology and Oncology Laboratory, University of Concepcion, Concepcion (Chile); Department of Medical Specialties, School of Medicine, University of Concepcion, Concepcion (Chile); Department of Urology, State University of New York at Buffalo, NY (United States)

    2015-11-27

    Prostate cancer (CaP) bone metastasis is an early event that remains inactive until later-stage progression. Reduced levels of circulating androgens, due to andropause or androgen deprivation therapies, alter androgen receptor (AR) coactivator expression. Coactivators shift the balance towards enhanced AR-mediated gene transcription that promotes progression to androgen-resistance. Disruptions in coregulators may represent a molecular switch that reactivates latent bone metastasis. Changes in AR-mediated transcription in androgen-sensitive LNCaP and androgen-resistant C4-2 cells were analyzed for AR coregulator recruitment in co-culture with Saos-2 and THP-1. The Saos-2 cell line derived from human osteosarcoma and THP-1 cell line representing human monocytes were used to display osteoblast and osteoclast activity. Increased AR activity in androgen-resistant C4-2 was due to increased AR expression and SRC1/TIF2 recruitment and decreased SMRT/NCoR expression. AR activity in both cell types was decreased over 90% when co-cultured with Saos-2 or THP-1 due to dissociation of AR from the SRC1/TIF2 and SMRT/NCoR coregulators complex, in a ligand-dependent and cell-type specific manner. In the absence of androgens, Saos-2 decreased while THP-1 increased proliferation of LNCaP cells. In contrast, both Saos-2 and THP-1 decreased proliferation of C4-2 in absence and presence of androgens. Global changes in gene expression from both CaP cell lines identified potential cell cycle and androgen regulated genes as mechanisms for changes in cell proliferation and AR-mediated transactivation in the context of bone marrow stroma cells. - Highlights: • Decreased corepressor expression change AR in androgen-resistance prostate cancer. • Bone stroma-derived cells change AR coregulator recruitment in prostate cancer. • Bone stroma cells change cell proliferation in androgen-resistant cancer cells. • Global gene expression in CaP cells is modified by bone stroma cells in co

  1. Anti-androgen effects of cypermethrin on the amino- and carboxyl-terminal interaction of the androgen receptor

    International Nuclear Information System (INIS)

    Hu, Jin-xia; Li, Yan-fang; Pan, Chen; Zhang, Jin-peng; Wang, Hong-mei; Li, Jing; Xu, Li-chun

    2012-01-01

    Graphical abstract: Both the known AR antagonist nilutamide and the pyrethroid insecticide cypermethrin inhibited DHT-induced AR N/C interaction in the mammalian two-hybrid assay. However, cypermethrin was a weaker androgen antagonist than nilutamide. Highlights: ► We have developed the mammalian two-hybrid assay. ► The assay displayed appropriate response to DHT and nilutamide. ► The N/C interaction was induced by DHT in a dose-dependent manner. ► Nilutamide inhibited DHT-induced AR N/C interaction. ► Cypermethrin exhibits inhibitory effects on DHT-induced AR N/C interaction. -- Abstract: The pyrethroid insecticide, cypermethrin has been demonstrated to be an environmental anti-androgen in the androgen receptor (AR) reporter gene assay. The amino- and carboxyl-terminal (N/C) interaction is required for transcription potential of the AR. In order to characterize the anti-androgen effects of cypermethrin involved in the N/C interaction of AR, the mammalian two-hybrid assay has been developed in the study. The fusion vectors pVP16-ARNTD, pM-ARLBD and the pG5CAT Reporter Vector were cotransfected into the CV-1 cells. The assay displayed appropriate response to the potent, classical AR agonist 5α-dihydrotestosterone (DHT) and known AR antagonist nilutamide. The N/C interaction was induced by DHT from 10 −11 M to 10 −5 M in a dose-dependent manner. Nilutamide did not activate N/C interaction, while inhibited DHT-induced AR N/C interaction at the concentrations from 10 −7 M to 10 −5 M. Treatment of CV-1 cells with cypermethrin alone did not activate the reporter CAT. Cypermethrin significantly decreased the DHT-induced reporter CAT expression at the higher concentration of 10 −5 M. The mammalian two-hybrid assay provides a promising tool both for defining mechanism involved in AR N/C interaction of EDCs and for screening of chemicals with androgen agonistic and antagonistic activities. Cypermethrin exhibits inhibitory effects on the DHT-induced AR N

  2. Expression of androgen receptor and prostate-specific antigen in male breast carcinoma

    International Nuclear Information System (INIS)

    Kidwai, Noman; Gong, Yun; Sun, Xiaoping; Deshpande, Charuhas G; Yeldandi, Anjana V; Rao, M Sambasiva; Badve, Sunil

    2004-01-01

    The androgen-regulated proteins prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP) are present in high concentrations in normal prostate and prostatic cancer and are considered to be tissue-specific to prostate. These markers are commonly used to diagnose metastatic prostate carcinoma at various sites including the male breast. However, expression of these two proteins in tumors arising in tissues regulated by androgens such as male breast carcinoma has not been thoroughly evaluated. In this study we analyzed the expression of PSA, PSAP and androgen receptor (AR) by immunohistochemistry in 26 cases of male breast carcinomas and correlated these with the expression of other prognostic markers. AR, PSA and PSAP expression was observed in 81%, 23% and 0% of carcinomas, respectively. Combined expression of AR and PSA was observed in only four tumors. Although the biological significance of PSA expression in male breast carcinomas is not clear, caution should be exercised when it is used as a diagnostic marker of metastatic prostate carcinoma

  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. Effect of organochlorine pesticides on human androgen receptor activation in vitro

    International Nuclear Information System (INIS)

    Lemaire, Geraldine; Terouanne, Beatrice; Mauvais, Pascale; Michel, Serge; Rahmani, Roger

    2004-01-01

    Many persistent organochlorine pesticides (OCs) have been implicated in adverse effects, that is, reproductive and developmental effects, in man and in wildlife alike. It has been hypothesized that these so-called xeno-hormones could be responsible for the increased incidence in various male sexual differentiation disorders such as hypospadias, cryptorchidism, low sperm counts and quality. In this report, OCs, called endocrine disrupters, were tested for their interaction with the androgen receptor. The stable prostatic cell line PALM, which contains a human androgen receptor (hAR) expression vector and the reporter MMTV-luciferase, was used to characterize the response of hAR to OC and was compared with synthetic androgen compound R1881. We found that all the OC pesticides tested were able to shift the agonist [ 3 H]-R1881 from its binding site to the AR in competitive binding assays. In addition, these compounds antagonize - in a dose-dependent manner - the AR-mediated transcription by synthetic AR ligand R1881. None of the pesticides reacted as agonists. These results demonstrate that OC endocrine activities in vivo probably result from direct and specific binding to the AR ligand-binding domain. Although the antagonistic potential of OC pesticides is lower than that of hydroxyflutamide, they are capable of disrupting the male hormone signaling pathway. Because these chemicals are extremely persistent and tend to bioaccumulate, these results support the hypothesis that the recent increase in the incidence of male sexual disorders could be due to long exposure to ubiquitous OC pesticides found in the environment

  5. Identification of novel androgen receptor target genes in prostate cancer

    Directory of Open Access Journals (Sweden)

    Gerald William L

    2007-06-01

    Full Text Available Abstract Background The androgen receptor (AR plays critical roles in both androgen-dependent and castrate-resistant prostate cancer (PCa. However, little is known about AR target genes that mediate the receptor's roles in disease progression. Results Using Chromatin Immunoprecipitation (ChIP Display, we discovered 19 novel loci occupied by the AR in castrate resistant C4-2B PCa cells. Only four of the 19 AR-occupied regions were within 10-kb 5'-flanking regulatory sequences. Three were located up to 4-kb 3' of the nearest gene, eight were intragenic and four were in gene deserts. Whereas the AR occupied the same loci in C4-2B (castrate resistant and LNCaP (androgen-dependent PCa cells, differences between the two cell lines were observed in the response of nearby genes to androgens. Among the genes strongly stimulated by DHT in C4-2B cells – D-dopachrome tautomerase (DDT, Protein kinase C delta (PRKCD, Glutathione S- transferase theta 2 (GSTT2, Transient receptor potential cation channel subfamily V member 3 (TRPV3, and Pyrroline-5-carboxylate reductase 1 (PYCR1 – most were less strongly or hardly stimulated in LNCaP cells. Another AR target gene, ornithine aminotransferase (OAT, was AR-stimulated in a ligand-independent manner, since it was repressed by AR siRNA knockdown, but not stimulated by DHT. We also present evidence for in vivo AR-mediated regulation of several genes identified by ChIP Display. For example, PRKCD and PYCR1, which may contribute to PCa cell growth and survival, are expressed in PCa biopsies from primary tumors before and after ablation and in metastatic lesions in a manner consistent with AR-mediated stimulation. Conclusion AR genomic occupancy is similar between LNCaP and C4-2B cells and is not biased towards 5' gene flanking sequences. The AR transcriptionally regulates less than half the genes nearby AR-occupied regions, usually but not always, in a ligand-dependent manner. Most are stimulated and a few are

  6. 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

  7. Design and synthesis of tricyclic tetrahydroquinolines as a new series of nonsteroidal selective androgen receptor modulators (SARMs).

    Science.gov (United States)

    Nagata, Naoya; Miyakawa, Motonori; Amano, Seiji; Furuya, Kazuyuki; Yamamoto, Noriko; Inoguchi, Kiyoshi

    2011-03-15

    Some tricyclic tetrahydroquinolines (THQs) were found to have the potential of a new series of nonsteroidal selective androgen receptor modulators (SARMs). Compound 5b was first designed and synthesized under our hypothesis based on a four-point pharmacophoric requirement of the 3-carbonyl, 18-methyl, 17-hydroxyl, and 13-quaternary carbon groups of dihydrotestosterone (DHT). It was revealed that this compound exhibits not only a strong androgen receptor (AR) agonistic activity (EC(50)=9.2 nM) but also the highest selectivity in binding affinity to AR among the steroid hormone receptors. Furthermore, this compound showed a weak virilizing effect with retention of the desired anabolic effect as compared with DHT in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Fundamental considerations in the design of fluorine-18 labeled progestins and androgens as imaging agents for receptor-positive tumors of the breast and prostate

    International Nuclear Information System (INIS)

    Brandes, S.J.; Katzenellenbogen, J.A.

    1988-01-01

    A review is given of the structural and functional features which are important in the design and development of imaging agents for the progesterone receptor (PR) and the androgen receptor (AR) directed towards imaging receptor-positive tumors in the breast and prostate respectively. In particular the effects of various substituents on the biological activities and homologous receptor binding of progesterone, testosterone, nortestosterone and dihydrotestosterone are discussed. The effect of fluorine substitution on the affinities of progestins and androgens for their respective receptors is described. Other ligand systems that have high affinity for AR and PR and which may provide good bases for the design of fluorine-substituted imaging agents are also discussed. Finally, previous studies with radiolabelled progestins and androgens are described. (U.K.)

  9. Phosphorylation and Internalization of Lysophosphatidic Acid Receptors LPA1, LPA2, and LPA3.

    Directory of Open Access Journals (Sweden)

    Rocío Alcántara-Hernández

    Full Text Available The lysophosphatidic acid receptors LPA1, LPA2, and LPA3 were individually expressed in C9 cells and their signaling and regulation were studied. Agonist-activation increases intracellular calcium concentration in a concentration-dependent fashion. Phorbol myristate acetate markedly inhibited LPA1- and LPA3-mediated effect, whereas that mediated by LPA2 was only partially diminished; the actions of the phorbol ester were inhibited by bisindolylmaleimide I and by overnight incubation with the protein kinase C activator, which leads to down regulation of this protein kinase. Homologous desensitization was also observed for the three LPA receptors studied, with that of LPA2 receptors being consistently of lesser magnitude; neither inhibition nor down-regulation of protein kinase C exerted any effect on homologous desensitization. Activation of LPA1-3 receptors induced ERK 1/2 phosphorylation; this effect was markedly attenuated by inhibition of epidermal growth factor receptor tyrosine kinase activity, suggesting growth factor receptor transactivation in this effect. Lysophosphatidic acid and phorbol myristate acetate were able to induce LPA1-3 phosphorylation, in time- and concentration-dependent fashions. It was also clearly observed that agonists and protein kinase C activation induced internalization of these receptors. Phosphorylation of the LPA2 subtype required larger concentrations of these agents and its internalization was less intense than that of the other subtypes.Our data show that these three LPA receptors are phosphoproteins whose phosphorylation state is modulated by agonist-stimulation and protein kinase C-activation and that differences in regulation and cellular localization exist, among the subtypes.

  10. Phosphorylation site dynamics of early T-cell receptor signaling

    DEFF Research Database (Denmark)

    Chylek, Lily A; Akimov, Vyacheslav; Dengjel, Jörn

    2014-01-01

    In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack...... that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites...... a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found...

  11. 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.

  12. Identification and characterisation of an androgen receptor from zebrafish Danio rerio

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Andersen, Ole; Bjerregaard, Poul

    2007-01-01

    ) and goldfish (Carassius auratus). Binding assays with zfAR demonstrated high affinity, saturable, single class binding site, with the characteristics of an androgen receptor. Saturation experiments along with subsequent Scatchard analysis determined that the Kd of the zfAR for 3H-testosterone was 2 n...

  13. Identification of the functional domains of ANT-1, a novel coactivator of the androgen receptor

    International Nuclear Information System (INIS)

    Fan Shuli; Goto, Kiminobu; Chen Guangchun; Morinaga, Hidetaka; Nomura, Masatoshi; Okabe, Taijiro; Nawata, Hajime; Yanase, Toshihiko

    2006-01-01

    Previously, we identified a transcriptional coactivator for the activation function-1 (AF-1) domain of the human androgen receptor (AR) and designated it androgen receptor N-terminal domain transactivating protein-1 (ANT-1). This coactivator, which contains multiple tetratricopeptide repeat (TPR) motifs from amino acid (aa) 294, is identical to a component of U5 small nuclear ribonucleoprotein particles and binds specifically to the AR or glucocorticoid receptor. Here, we identified four distinct functional domains. The AR-AF-1-binding domain, which bound to either aa 180-360 or 360-532 in AR-AF-1, clearly overlapped with TAU-1 and TAU-5. This domain and the subnuclear speckle formation domain in ANT-1 were assigned within the TPR motifs, while the transactivating and nuclear localization signal domains resided within the N-terminal sequence. The existence of these functional domains may further support the idea that ANT-1 can function as an AR-AF-1-specific coactivator while mediating a transcription-splicing coupling

  14. Androgen receptor signalling in Vascular Endothelial cells is dispensable for spermatogenesis and male fertility

    Directory of Open Access Journals (Sweden)

    O'Hara Laura

    2012-01-01

    Full Text Available Abstract Background Androgen signalling is essential both for male development and function of the male reproductive system in adulthood. Within the adult testis, Germ cells (GC do not express androgen receptor (AR suggesting androgen-mediated promotion of spermatogenesis must act via AR-expressing somatic cell-types. Several recent studies have exploited the Cre/lox system of conditional gene-targeting to ablate AR function from key somatic cell-types in order to establish the cell-specific role of AR in promotion of male fertility. In this study, we have used a similar approach to specifically ablate AR-signalling from Vascular Endothelial (VE cells, with a view to defining the significance of androgen signalling within this cell-type on spermatogenesis. Findings AR expression in VE cells of the testicular vasculature was confirmed using an antibody against AR. A Cre-inducible fluorescent reporter line was used to empirically establish the utility of a mouse line expressing Cre Recombinase driven by the Tie2-Promoter, for targeting VE cells. Immunofluorescent detection revealed expression of YFP (and therefore Cre Recombinase function limited to VE cells and an interstitial population of cells, believed to be macrophages, that did not express AR. Mating of Tie2-Cre males to females carrying a floxed AR gene produced Vascular Endothelial Androgen Receptor Knockout (VEARKO mice and littermate controls. Ablation of AR from all VE cells was confirmed; however, no significant differences in bodyweight or reproductive tissue weights could be detected in VEARKO animals and spermatogenesis and fertility was unaffected. Conclusions We demonstrate the successful generation and empirical validation of a cell-specific knockout of AR from VE cells, and conclude that AR expression in VE cells is not essential for spermatogenesis or male fertility.

  15. Growth hormone-dependent phosphorylation of tyrosine 333 and/or 338 of the growth hormone receptor

    DEFF Research Database (Denmark)

    VanderKuur, J A; Wang, X; Zhang, L

    1995-01-01

    and a reduction of GH-dependent phosphorylation of the full-length receptor. Consistent with Tyr333 and/or Tyr338 serving as substrates of JAK2, these substitutions resulted in a loss of tyrosyl phosphorylation of truncated receptor in an in vitro kinase assay using substantially purified GH.GHR.JAK2 complexes...

  16. Therapeutic targeting of angiotensin II receptor type 1 to regulate androgen receptor in prostate cancer.

    Science.gov (United States)

    Takahashi, Satoru; Uemura, Hiroji; Seeni, Azman; Tang, Mingxi; Komiya, Masami; Long, Ne; Ishiguro, Hitoshi; Kubota, Yoshinobu; Shirai, Tomoyuki

    2012-10-01

    With the limited strategies for curative treatment of castration-resistant prostate cancer (CRPC), public interest has focused on the potential prevention of prostate cancer. Recent studies have demonstrated that an angiotensin II receptor blocker (ARB) has the potential to decrease serum prostate-specific antigen (PSA) level and improve performance status in CRPC patients. These facts prompted us to investigate the direct effects of ARBs on prostate cancer growth and progression. Transgenic rat for adenocarcinoma of prostate (TRAP) model established in our laboratory was used. TRAP rats of 3 weeks of age received ARB (telmisartan or candesartan) at the concentration of 2 or 10 mg/kg/day in drinking water for 12 weeks. In vitro analyses for cell growth, ubiquitylation or reporter gene assay were performed using LNCaP cells. We found that both telmisartan and candesartan attenuated prostate carcinogenesis in TRAP rats by augmentation of apoptosis resulting from activation of caspases, inactivation of p38 MAPK and down-regulation of the androgen receptor (AR). Further, microarray analysis demonstrated up-regulation of estrogen receptor β (ERβ) by ARB treatment. In both parental and androgen-independent LNCaP cells, ARB inhibited both cell growth and AR-mediated transcriptional activity. ARB also exerted a mild additional effect on AR-mediated transcriptional activation by the ERβ up-regulation. An intervention study revealed that PSA progression was prolonged in prostate cancer patients given an ARB compared with placebo control. These data provide a new concept that ARBs are promising potential chemopreventive and chemotherapeutic agents for prostate cancer. Copyright © 2012 Wiley Periodicals, Inc.

  17. Modulation of Androgen Receptor Transcriptional Activity

    NARCIS (Netherlands)

    H.Y. Wong (Hao Yun)

    2009-01-01

    textabstractAndrogens, testosterone (T) and 5a-dihydrotestosterone (DHT), are important for male and female physiology, in particular for male sexual differentiation, development of secondary male characteristics and spermatogenesis. These hormones exert their actions by binding to the androgen

  18. 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

  19. Identifying Environmental Chemicals as Agonists of the Androgen Receptor by Applying a Quantitative High-throughput Screening Platform

    Science.gov (United States)

    Background: The androgen receptor (AR, NR3C4) is a nuclear receptor whose main function is acting as a transcription factor regulating gene expression for male sexual development and maintaining accessory sexual organ function. It is also a necessary component of female fertility...

  20. In Vitro Androgen Bioassays as a Detection Method for Designer Androgens

    Directory of Open Access Journals (Sweden)

    Alison K. Heather

    2013-02-01

    Full Text Available Androgens are the class of sex steroids responsible for male sexual characteristics, including increased muscle mass and decreased fat mass. Illicit use of androgen doping can be an attractive option for those looking to enhance sporting performance and/or physical appearance. The use of in vitro bioassays to detect androgens, especially designer or proandrogens, is becoming increasingly important in combating androgen doping associated with nutritional supplements. The nutritional sports supplement market has grown rapidly throughout the past decade. Many of these supplements contain androgens, designer androgens or proandrogens. Many designer or proandrogens cannot be detected by the standard highly-sensitive screening methods such as gas chromatography-mass spectrometry because their chemical structure is unknown. However, in vitro androgen bioassays can detect designer and proandrogens as these assays are not reliant on knowing the chemical structure but instead are based on androgen receptor activation. For these reasons, it may be advantageous to use routine androgen bioassay screening of nutraceutical samples to help curb the increasing problem of androgen doping.

  1. Inhibition of androgen receptor by decoy molecules delays progression to castration-recurrent prostate cancer.

    Directory of Open Access Journals (Sweden)

    Jae-Kyung Myung

    Full Text Available Androgen receptor (AR is a member of the steroid receptor family and a therapeutic target for all stages of prostate cancer. AR is activated by ligand binding within its C-terminus ligand-binding domain (LBD. Here we show that overexpression of the AR NTD to generate decoy molecules inhibited both the growth and progression of prostate cancer in castrated hosts. Specifically, it was shown that lentivirus delivery of decoys delayed hormonal progression in castrated hosts as indicated by increased doubling time of tumor volume, prolonged time to achieve pre-castrate levels of serum prostate-specific antigen (PSA and PSA nadir. These clinical parameters are indicative of delayed hormonal progression and improved therapeutic response and prognosis. Decoys reduced the expression of androgen-regulated genes that correlated with reduced in situ interaction of the AR with androgen response elements. Decoys did not reduce levels of AR protein or prevent nuclear localization of the AR. Nor did decoys interact directly with the AR. Thus decoys did not inhibit AR transactivation by a dominant negative mechanism. This work provides evidence that the AR NTD plays an important role in the hormonal progression of prostate cancer and supports the development of AR antagonists that target the AR NTD.

  2. Molecular mechanisms of androgen receptor functions

    NARCIS (Netherlands)

    K. Steketee (Karine)

    2007-01-01

    textabstractThe androgens testosterone (T) and dihydrotestosterone (DHT) are steroid hormones, which are necessary for development and maintenance of the functions of the male sex organs, including the prostate. Androgens also play an important role in benign abnormalities of the prostate and in the

  3. Phosphorylation of SLP-76 by the ZAP-70 protein-tyrosine kinase is required for T-cell receptor function.

    Science.gov (United States)

    Bubeck Wardenburg, J; Fu, C; Jackman, J K; Flotow, H; Wilkinson, S E; Williams, D H; Johnson, R; Kong, G; Chan, A C; Findell, P R

    1996-08-16

    Two families of tyrosine kinases, the Src and Syk families, are required for T-cell receptor activation. While the Src kinases are responsible for phosphorylation of receptor-encoded signaling motifs and for up-regulation of ZAP-70 activity, the downstream substrates of ZAP-70 are unknown. Evidence is presented herein that the Src homology 2 (SH2) domain-containing leukocyte protein of 76 kDa (SLP-76) is a substrate of ZAP-70. Phosphorylation of SLP-76 is diminished in T cells that express a catalytically inactive ZAP-70. Moreover, SLP-76 is preferentially phosphorylated by ZAP-70 in vitro and in heterologous cellular systems. In T cells, overexpression of wild-type SLP-76 results in a hyperactive receptor, while expression of a SLP-76 molecule that is unable to be tyrosine-phosphorylated attenuates receptor function. In addition, the SH2 domain of SLP-76 is required for T-cell receptor function, although its role is independent of the ability of SLP-76 to undergo tyrosine phosphorylation. As SLP-76 interacts with both Grb2 and phospholipase C-gamma1, these data indicate that phosphorylation of SLP-76 by ZAP-70 provides an important functional link between the T-cell receptor and activation of ras and calcium pathways.

  4. Differential regulation of the transcriptional activity of the glucocorticoid receptor through site-specific phosphorylation

    Directory of Open Access Journals (Sweden)

    Raj Kumar

    2008-08-01

    Full Text Available Raj Kumar1, William J Calhoun21Division of Gastroenterology; 2Division of Allergy, Pulmonary, Immunology, Critical Care, and Sleep (APICS, Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USAAbstract: Post-translational modifications such as phosphorylation are known to play an important role in the gene regulation by the transcription factors including the nuclear hormone receptor superfamily of which the glucocorticoid receptor (GR is a member. Protein phosphorylation often switches cellular activity from one state to another. Like many other transcription factors, the GR is a phosphoprotein, and phosphorylation plays an important role in the regulation of GR activity. Cell signaling pathways that regulate phosphorylation of the GR and its associated proteins are important determinants of GR function under various physiological conditions. While the role of many phosphorylation sites in the GR is still not fully understood, the role of others is clearer. Several aspects of transcription factor function, including DNA binding affinity, interaction of transactivation domains with the transcription initiation complex, and shuttling between the cytoplasmic compartments, have all been linked to site-specific phosphorylation. All major phosphorylation sites in the human GR are located in the N-terminal domain including the major transactivation domain, AF1. Available literature clearly indicates that many of these potential phosphorylation sites are substrates for multiple kinases, suggesting the potential for a very complex regulatory network. Phosphorylated GR interacts favorably with critical coregulatory proteins and subsequently enhances transcriptional activity. In addition, the activities and specificities of coregulators may be subject to similar regulation by phosphorylation. Regulation of the GR activity due to phosphorylation appears to be site-specific and dependent upon specific cell signaling cascade

  5. 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...

  6. Identification of the molecular switch that regulates access of 5alpha-DHT to the androgen receptor.

    Science.gov (United States)

    Penning, Trevor M; Bauman, David R; Jin, Yi; Rizner, Tea Lanisik

    2007-02-01

    Pairs of hydroxysteroid dehydrogenases (HSDs) govern ligand access to steroid receptors in target tissues and act as molecular switches. By acting as reductases or oxidases, HSDs convert potent ligands into their cognate inactive metabolites or vice versa. This pre-receptor regulation of steroid hormone action may have profound effects on hormonal response. We have identified the HSDs responsible for regulating ligand access to the androgen receptor (AR) in human prostate. Type 3 3alpha-hydroxysteroid dehydrogenase (aldo-keto reductase 1C2) acts solely as a reductase to convert 5alpha-dihydrotestosterone (DHT), a potent ligand for the AR (K(d)=10(-11)M for the AR), to the inactive androgen 3alpha-androstanediol (K(d)=10(-6)M for the AR); while RoDH like 3alpha-HSD (a short-chain dehydrogenase/reductase (SDR)) acts solely as an oxidase to convert 3alpha-androstanediol back to 5alpha-DHT. Our studies suggest that aldo-keto reductase (AKRs) and SDRs function as reductases and oxidases, respectively, to control ligand access to nuclear receptors.

  7. Testosterone regulates keratin 33B expression in rat penis growth through androgen receptor signaling.

    Science.gov (United States)

    Ma, Yan-Min; Wu, Kai-Jie; Dang, Qiang; Shi, Qi; Gao, Yang; Guo, Peng; Xu, Shan; Wang, Xin-Yang; He, Da-Lin; Gong, Yong-Guang

    2014-01-01

    Androgen therapy is the mainstay of treatment for the hypogonadotropic hypogonadal micropenis because it obviously enhances penis growth in prepubescent microphallic patients. However, the molecular mechanisms of androgen treatment leading to penis growth are still largely unknown. To clarify this well-known phenomenon, we successfully generated a castrated male Sprague Dawley rat model at puberty followed by testosterone administration. Interestingly, compared with the control group, testosterone treatment stimulated a dose-dependent increase of penis weight, length, and width in castrated rats accompanied with a dramatic recovery of the pathological changes of the penis. Mechanistically, testosterone administration substantially increased the expression of androgen receptor (AR) protein. Increased AR protein in the penis could subsequently initiate transcription of its target genes, including keratin 33B (Krt33b). Importantly, we demonstrated that KRT33B is generally expressed in the rat penis and that most KRT33B expression is cytoplasmic. Furthermore, AR could directly modulate its expression by binding to a putative androgen response element sequence of the Krt33b promoter. Overall, this study reveals a novel mechanism facilitating penis growth after testosterone treatment in precastrated prepubescent animals, in which androgen enhances the expression of AR protein as well as its target genes, such as Krt33b.

  8. Testosterone regulates keratin 33B expression in rat penis growth through androgen receptor signaling

    Directory of Open Access Journals (Sweden)

    Yan-Min Ma

    2014-12-01

    Full Text Available Androgen therapy is the mainstay of treatment for the hypogonadotropic hypogonadal micropenis because it obviously enhances penis growth in prepubescent microphallic patients. However, the molecular mechanisms of androgen treatment leading to penis growth are still largely unknown. To clarify this well-known phenomenon, we successfully generated a castrated male Sprague Dawley rat model at puberty followed by testosterone administration. Interestingly, compared with the control group, testosterone treatment stimulated a dose-dependent increase of penis weight, length, and width in castrated rats accompanied with a dramatic recovery of the pathological changes of the penis. Mechanistically, testosterone administration substantially increased the expression of androgen receptor (AR protein. Increased AR protein in the penis could subsequently initiate transcription of its target genes, including keratin 33B (Krt33b. Importantly, we demonstrated that KRT33B is generally expressed in the rat penis and that most KRT33B expression is cytoplasmic. Furthermore, AR could directly modulate its expression by binding to a putative androgen response element sequence of the Krt33b promoter. Overall, this study reveals a novel mechanism facilitating penis growth after testosterone treatment in precastrated prepubescent animals, in which androgen enhances the expression of AR protein as well as its target genes, such as Krt33b.

  9. Restoration of the cellular secretory milieu overrides androgen dependence of in vivo generated castration resistant prostate cancer cells overexpressing the androgen receptor.

    Science.gov (United States)

    Patki, Mugdha; Huang, Yanfang; Ratnam, Manohar

    2016-07-22

    It is believed that growth of castration resistant prostate cancer (CRPC) cells is enabled by sensitization to minimal residual post-castrate androgen due to overexpression of the androgen receptor (AR). Evidence is derived from androgen-induced colony formation in the absence of cell-secreted factors or from studies involving forced AR overexpression in hormone-dependent cells. On the other hand, standard cell line models established from CRPC patient tumors (e.g., LNCaP and VCaP) are hormone-dependent and require selection pressure in castrated mice to re-emerge as CRPC cells and the resulting tumors then tend to be insensitive to the androgen antagonist enzalutamide. Therefore, we examined established CRPC model cells produced by castration of mice bearing hormone-dependent cell line xenografts including CRPC cells overexpressing full-length AR (C4-2) or co-expressing wtAR and splice-variant AR-V7 that is incapable of ligand binding (22Rv1). In standard colony formation assays, C4-2 cells were shown to be androgen-dependent and sensitive to enzalutamide whereas 22Rv1 cells were incapable of colony formation under identical conditions. However, both C4-2 and 22Rv1 cells formed colonies in conditioned media derived from the same cells or from HEK293 fibroblasts that were proven to lack androgenic activity. This effect was (i) not enhanced by androgen, (ii) insensitive to enzalutamide, (iii) dependent on AR (in C4-2) and on AR-V7 and wtAR (in 22Rv1) and (iv) sensitive to inhibitors of several signaling pathways, similar to androgen-stimulation. Therefore, during progression to CRPC in vivo, coordinate cellular changes accompanying overexpression of AR may enable cooperation between hormone-independent activity of AR and actions of cellular secretory factors to completely override androgen-dependence and sensitivity to drugs targeting hormonal factors. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Androgen receptor-negative human prostate cancer cells induce osteogenesis in mice through FGF9-mediated mechanisms.

    Science.gov (United States)

    Li, Zhi Gang; Mathew, Paul; Yang, Jun; Starbuck, Michael W; Zurita, Amado J; Liu, Jie; Sikes, Charles; Multani, Asha S; Efstathiou, Eleni; Lopez, Adriana; Wang, Jing; Fanning, Tina V; Prieto, Victor G; Kundra, Vikas; Vazquez, Elba S; Troncoso, Patricia; Raymond, Austin K; Logothetis, Christopher J; Lin, Sue-Hwa; Maity, Sankar; Navone, Nora M

    2008-08-01

    In prostate cancer, androgen blockade strategies are commonly used to treat osteoblastic bone metastases. However, responses to these therapies are typically brief, and the mechanism underlying androgen-independent progression is not clear. Here, we established what we believe to be the first human androgen receptor-negative prostate cancer xenografts whose cells induced an osteoblastic reaction in bone and in the subcutis of immunodeficient mice. Accordingly, these cells grew in castrated as well as intact male mice. We identified FGF9 as being overexpressed in the xenografts relative to other bone-derived prostate cancer cells and discovered that FGF9 induced osteoblast proliferation and new bone formation in a bone organ assay. Mice treated with FGF9-neutralizing antibody developed smaller bone tumors and reduced bone formation. Finally, we found positive FGF9 immunostaining in prostate cancer cells in 24 of 56 primary tumors derived from human organ-confined prostate cancer and in 25 of 25 bone metastasis cases studied. Collectively, these results suggest that FGF9 contributes to prostate cancer-induced new bone formation and may participate in the osteoblastic progression of prostate cancer in bone. Androgen receptor-null cells may contribute to the castration-resistant osteoblastic progression of prostate cancer cells in bone and provide a preclinical model for studying therapies that target these cells.

  11. Androgen-androgen receptor system improves chronic inflammatory conditions by suppressing monocyte chemoattractant protein-1 gene expression in adipocytes via transcriptional regulation

    Energy Technology Data Exchange (ETDEWEB)

    Morooka, Nobukatsu, E-mail: amorooka@gunma-u.ac.jp [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Ueguri, Kei [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Yee, Karen Kar Lye [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Human Resources Cultivation Center, Gunma University, 1-5-1 Tenjin-cho, Kiryushi, Gunma, 376-8515 (Japan); Yanase, Toshihiko [Department of Endocrinology and Diabetes Mellitus, School of Medicine, Fukuoka University, Jonan-ku, Fukuoka, 814-0180 (Japan); Sato, Takashi [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan)

    2016-09-02

    Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatory macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. - Highlights: • DHT, non-aromatizable androgen suppresses Mcp-1 expression in adipocytes. • Mcp-1 transcription was negatively regulated by DHT-AR action. • DHT-AR selectively regulates Mcp-1 transcription through distinct NF-κB sites.

  12. Androgen-androgen receptor system improves chronic inflammatory conditions by suppressing monocyte chemoattractant protein-1 gene expression in adipocytes via transcriptional regulation

    International Nuclear Information System (INIS)

    Morooka, Nobukatsu; Ueguri, Kei; Yee, Karen Kar Lye; Yanase, Toshihiko; Sato, Takashi

    2016-01-01

    Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatory macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. - Highlights: • DHT, non-aromatizable androgen suppresses Mcp-1 expression in adipocytes. • Mcp-1 transcription was negatively regulated by DHT-AR action. • DHT-AR selectively regulates Mcp-1 transcription through distinct NF-κB sites.

  13. Beyond T and DHT - novel steroid derivatives capable of wild type androgen receptor activation.

    Science.gov (United States)

    Mostaghel, Elahe A

    2014-01-01

    While androgen deprivation therapy (ADT) remains the primary treatment for metastatic prostate cancer (PCa), castration does not eliminate androgens from the prostate tumor microenvironment, and residual intratumoral androgens are implicated in nearly every mechanism by which androgen receptor (AR)-mediated signaling promotes castration-resistant disease. The uptake and intratumoral (intracrine) conversion of circulating adrenal androgens such as dehydroepiandrosterone sulfate (DHEA-S) to steroids capable of activating the wild type AR is a recognized driver of castration resistant prostate cancer (CRPC). However, less well-characterized adrenal steroids, including 11-deoxcorticosterone (DOC) and 11beta-hydroxyandrostenedione (11OH-AED) may also play a previously unrecognized role in promoting AR activation. In particular, recent data demonstrate that the 5α-reduced metabolites of DOC and 11OH-AED are activators of the wild type AR. Given the well-recognized presence of SRD5A activity in CRPC tissue, these observations suggest that in the low androgen environment of CRPC, alternative sources of 5α-reduced ligands may supplement AR activation normally mediated by the canonical 5α-reduced agonist, 5α-DHT. Herein we review the emerging data that suggests a role for these alternative steroids of adrenal origin in activating the AR, and discuss the enzymatic pathways and novel downstream metabolites mediating these effects. We conclude by discussing the potential implications of these findings for CRPC progression, particularly in context of new agents such as abiraterone and enzalutamide which target the AR-axis for prostate cancer therapy.

  14. Selective androgen receptor modulators (SARMs) negatively regulate triple-negative breast cancer growth and epithelial:mesenchymal stem cell signaling.

    Science.gov (United States)

    Narayanan, Ramesh; Ahn, Sunjoo; Cheney, Misty D; Yepuru, Muralimohan; Miller, Duane D; Steiner, Mitchell S; Dalton, James T

    2014-01-01

    The androgen receptor (AR) is the most highly expressed steroid receptor in breast cancer with 75-95% of estrogen receptor (ER)-positive and 40-70% of ER-negative breast cancers expressing AR. Though historically breast cancers were treated with steroidal androgens, their use fell from favor because of their virilizing side effects and the emergence of tamoxifen. Nonsteroidal, tissue selective androgen receptor modulators (SARMs) may provide a novel targeted approach to exploit the therapeutic benefits of androgen therapy in breast cancer. Since MDA-MB-453 triple-negative breast cancer cells express mutated AR, PTEN, and p53, MDA-MB-231 triple-negative breast cancer cells stably expressing wildtype AR (MDA-MB-231-AR) were used to evaluate the in vitro and in vivo anti-proliferative effects of SARMs. Microarray analysis and epithelial:mesenchymal stem cell (MSC) co-culture signaling studies were performed to understand the mechanisms of action. Dihydrotestosterone and SARMs, but not bicalutamide, inhibited the proliferation of MDA-MB-231-AR. The SARMs reduced the MDA-MB-231-AR tumor growth and tumor weight by greater than 90%, compared to vehicle-treated tumors. SARM treatment inhibited the intratumoral expression of genes and pathways that promote breast cancer development through its actions on the AR. SARM treatment also inhibited the metastasis-promoting paracrine factors, IL6 and MMP13, and subsequent migration and invasion of epithelial:MSC co-cultures. 1. AR stimulation inhibits paracrine factors that are important for MSC interactions and breast cancer invasion and metastasis. 2. SARMs may provide promise as novel targeted therapies to treat AR-positive triple-negative breast cancer.

  15. Selective androgen receptor modulators (SARMs negatively regulate triple-negative breast cancer growth and epithelial:mesenchymal stem cell signaling.

    Directory of Open Access Journals (Sweden)

    Ramesh Narayanan

    Full Text Available The androgen receptor (AR is the most highly expressed steroid receptor in breast cancer with 75-95% of estrogen receptor (ER-positive and 40-70% of ER-negative breast cancers expressing AR. Though historically breast cancers were treated with steroidal androgens, their use fell from favor because of their virilizing side effects and the emergence of tamoxifen. Nonsteroidal, tissue selective androgen receptor modulators (SARMs may provide a novel targeted approach to exploit the therapeutic benefits of androgen therapy in breast cancer.Since MDA-MB-453 triple-negative breast cancer cells express mutated AR, PTEN, and p53, MDA-MB-231 triple-negative breast cancer cells stably expressing wildtype AR (MDA-MB-231-AR were used to evaluate the in vitro and in vivo anti-proliferative effects of SARMs. Microarray analysis and epithelial:mesenchymal stem cell (MSC co-culture signaling studies were performed to understand the mechanisms of action.Dihydrotestosterone and SARMs, but not bicalutamide, inhibited the proliferation of MDA-MB-231-AR. The SARMs reduced the MDA-MB-231-AR tumor growth and tumor weight by greater than 90%, compared to vehicle-treated tumors. SARM treatment inhibited the intratumoral expression of genes and pathways that promote breast cancer development through its actions on the AR. SARM treatment also inhibited the metastasis-promoting paracrine factors, IL6 and MMP13, and subsequent migration and invasion of epithelial:MSC co-cultures.1. AR stimulation inhibits paracrine factors that are important for MSC interactions and breast cancer invasion and metastasis. 2. SARMs may provide promise as novel targeted therapies to treat AR-positive triple-negative breast cancer.

  16. Androgen receptors and serum testosterone levels identify different subsets of postmenopausal breast cancers

    Directory of Open Access Journals (Sweden)

    Secreto Giorgio

    2012-12-01

    Full Text Available Abstract Background Androgen receptors (AR are frequently expressed in breast cancers, but their implication in cancer growth is still controversial. In the present study, we further investigated the role of the androgen/AR pathway in breast cancer development. Methods AR expression was evaluated by immunochemistry in a cohort of 528 postmenopausal breast cancer patients previously examined for the association of serum testosterone levels with patient and tumor characteristics. AR expression was classified according to the percentage of stained cells: AR-absent (0% and AR-poorly (1%-30%, AR-moderately (>30%-60%, and AR-highly (>60% positive. Results Statistical analysis was performed in 451 patients who experienced natural menopause. AR-high expression was significantly related with low histologic grade and estrogen receptor (ER- and progesterone receptor (PR-positive status (P trendP=0.022, although a trend across the AR expression categories was not present. When women defined by ER status were analyzed separately, regression analysis in the ER-positive group showed a significant association of high testosterone levels with AR-highly-positive expression (OR 1.86; 95% CI, 1.10-3.16, but the association was essentially due to patients greater than or equal to 65 years (OR 2.42; 95% CI, 1.22-4.82. In ER-positive group, elevated testosterone levels appeared also associated with AR-absent expression, although the small number of patients in this category limited the appearance of significant effects (OR 1.92; 95% CI, 0.73–5.02: the association was present in both age groups ( Conclusions The findings in the present study confirm that testosterone levels are a marker of hormone-dependent breast cancer and suggest that the contemporary evaluation of ER status, AR expression, and circulating testosterone levels may identify different subsets of cancers whose growth may be influenced by androgens.

  17. Size matters: Associations between the androgen receptor CAG repeat length and the intrafollicular hormone milieu

    DEFF Research Database (Denmark)

    Borgbo, T; Macek, M; Chrudimska, J

    2015-01-01

    Granulosa cell (GC) expressed androgen receptors (AR) and intrafollicular androgens are central to fertility. The transactivating domain of the AR contains a polymorphic CAG repeat sequence, which is linked to the transcriptional activity of AR and may influence the GC function. This study aims...... to evaluate the effects of the AR CAG repeat length on the intrafollicular hormone profiles, and the gene expression profiles of GC from human small antral follicles. In total, 190 small antral follicles (3-11 mm in diameter) were collected from 58 women undergoing ovarian cryopreservation for fertility...... expression compared to medium CAG repeat lengths (P = 0.03). In conclusion, long CAG repeat lengths in the AR were associated to significant attenuated levels of androgens and an increased conversion of testosterone into oestradiol, in human small antral follicles....

  18. Inhibition of Androgen Receptor Nuclear Localization and Castration-Resistant Prostate Tumor Growth by Pyrroloimidazole-based Small Molecules.

    Science.gov (United States)

    Masoodi, Khalid Z; Xu, Yadong; Dar, Javid A; Eisermann, Kurtis; Pascal, Laura E; Parrinello, Erica; Ai, Junkui; Johnston, Paul A; Nelson, Joel B; Wipf, Peter; Wang, Zhou

    2017-10-01

    The androgen receptor (AR) is a ligand-dependent transcription factor that controls the expression of androgen-responsive genes. A key step in androgen action, which is amplified in castration-resistant prostate cancer (CRPC), is AR nuclear translocation. Small molecules capable of inhibiting AR nuclear localization could be developed as novel therapeutics for CRPC. We developed a high-throughput screen and identified two structurally-related pyrroloimidazoles that could block AR nuclear localization in CRPC cells. We show that these two small molecules, 3-(4-ethoxyphenyl)-6,7-dihydro-5 H -pyrrolo[1,2- a ]imidazole (EPPI) and 3-(4-chlorophenyl)-6,7-dihydro-5 H -pyrrolo[1,2- a ]imidazole (CPPI) can inhibit the nuclear localization and transcriptional activity of AR and reduce the proliferation of AR-positive but not AR-negative prostate cancer cell lines. EPPI and CPPI did not inhibit nuclear localization of the glucocorticoid receptor or the estrogen receptor, suggesting they selectively target AR. In LNCaP tumor xenografts, CPPI inhibited the proliferation of relapsed LNCaP tumors. These findings suggest that EPPI and CPPI could serve as lead structures for the development of therapeutic agents for CRPC. Mol Cancer Ther; 16(10); 2120-9. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. Urokinase receptor expression involves tyrosine phosphorylation of phosphoglycerate kinase.

    Science.gov (United States)

    Shetty, Praveenkumar; Velusamy, Thirunavukkarasu; Bhandary, Yashodhar P; Liu, Ming C; Shetty, Sreerama

    2010-02-01

    The interaction of urokinase-type plasminogen activator (uPA) with its receptor, uPAR, plays a central role in several pathophysiological processes, including cancer. uPA induces its own cell surface receptor expression through stabilization of uPAR mRNA. The mechanism involves binding of a 51 nt uPAR mRNA coding sequence with phosphoglycerate kinase (PGK) to down regulate cell surface uPAR expression. Tyrosine phosphorylation of PGK mediated by uPA treatment enhances uPAR mRNA stabilization. In contrast, inhibition of tyrosine phosphorylation augments PGK binding to uPAR mRNA and attenuates uPA-induced uPAR expression. Mapping the specific peptide region of PGK indicated that its first quarter (amino acids 1-100) interacts with uPAR mRNA. To determine if uPAR expression by uPA is regulated through activation of tyrosine residues of PGK, we mutated the specific tyrosine residue and tested mutant PGK for its ability to interfere with uPAR expression. Inhibition of tyrosine phosphorylation by mutating Y76 residue abolished uPAR expression induced by uPA treatment. These findings collectively demonstrate that Y76 residue present in the first quarter of the PGK molecule is involved in lung epithelial cell surface uPAR expression. This region can effectively mimic the function of a whole PGK molecule in inhibiting tumor cell growth.

  20. Carboxyl-terminal multi-site phosphorylation regulates internalization and desensitization of the human sst2 somatostatin receptor.

    Science.gov (United States)

    Lehmann, Andreas; Kliewer, Andrea; Schütz, Dagmar; Nagel, Falko; Stumm, Ralf; Schulz, Stefan

    2014-04-25

    The somatostatin receptor 2 (sst2) is the pharmacological target of somatostatin analogs that are widely used in the diagnosis and treatment of human neuroendocrine tumors. We have recently shown that the stable somatostatin analogs octreotide and pasireotide (SOM230) stimulate distinct patterns of sst2 receptor phosphorylation and internalization. Like somatostatin, octreotide promotes the phosphorylation of at least six carboxyl-terminal serine and threonine residues namely S341, S343, T353, T354, T356 and T359, which in turn leads to a robust receptor endocytosis. Unlike somatostatin, pasireotide stimulates a selective phosphorylation of S341 and S343 of the human sst2 receptor followed by a partial receptor internalization. Here, we show that exchange of S341 and S343 by alanine is sufficient to block pasireotide-driven internalization, whereas mutation of T353, T354, T356 and T359 to alanine is required to strongly inhibited both octreotide- and somatostatin-induced internalization. Yet, combined mutation of T353, T354, T356 and T359 is not sufficient to prevent somatostatin-driven β-arrestin mobilization and receptor desensitization. Replacement of all fourteen carboxyl-terminal serine and threonine residues by alanine completely abrogates sst2 receptor internalization and β-arrestin mobilization in HEK293 cells. Together, our findings demonstrate for the first time that agonist-selective sst2 receptor internalization is regulated by multi-site phosphorylation of its carboxyl-terminal tail. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. A pp32-retinoblastoma protein complex modulates androgen receptor-mediated transcription and associates with components of the splicing machinery

    International Nuclear Information System (INIS)

    Adegbola, Onikepe; Pasternack, Gary R.

    2005-01-01

    We have previously shown pp32 and the retinoblastoma protein interact. pp32 and the retinoblastoma protein are nuclear receptor transcriptional coregulators: the retinoblastoma protein is a coactivator for androgen receptor, the major regulator of prostate cancer growth, while pp32, which is highly expressed in prostate cancer, is a corepressor of the estrogen receptor. We now show pp32 increases androgen receptor-mediated transcription and the retinoblastoma protein modulates this activity. Using affinity purification and mass spectrometry, we identify members of the pp32-retinoblastoma protein complex as PSF and nonO/p54nrb, proteins implicated in coordinate regulation of nuclear receptor-mediated transcription and splicing. We show that the pp32-retinoblastoma protein complex is modulated during TPA-induced K562 differentiation. Present evidence suggests that nuclear receptors assemble multiprotein complexes to coordinately regulate transcription and mRNA processing. Our results suggest that pp32 and the retinoblastoma protein may be part of a multiprotein complex that coordinately regulates nuclear receptor-mediated transcription and mRNA processing

  2. Relationship between serum response factor and androgen receptor in prostate cancer.

    Science.gov (United States)

    Prencipe, Maria; O'Neill, Amanda; O'Hurley, Gillian; Nguyen, Lan K; Fabre, Aurelie; Bjartell, Anders; Gallagher, William M; Morrissey, Colm; Kay, Elaine W; Watson, R William

    2015-11-01

    Serum response factor (SRF) is an important transcription factor in castrate-resistant prostate cancer (CRPC). Since CRPC is associated with androgen receptor (AR) hypersensitivity, we investigated the relationship between SRF and AR. Transcriptional activity was assessed by luciferase assay. Cell proliferation was measured by MTT and flow cytometry. Protein expression in patients was assessed by immunohistochemistry. To investigate AR involvement in SRF response to androgen, AR expression was down-regulated using siRNA. This resulted in the abrogation of SRF induction post-DHT. Moreover, DHT stimulation failed to induce SRF transcriptional activity in AR-negative PC346 DCC cells, which was only restored following AR over-expression. Next, SRF expression was down-regulated by siRNA, resulting in AR increased transcriptional activity in castrate-resistant LNCaP Abl cells but not in the parental LNCaP. This negative feedback loop in the resistant cells was confirmed by immunohistochemistry which showed a negative correlation between AR and SRF expression in CRPC bone metastases and a positive correlation in androgen-naïve prostatectomies. Cell proliferation was next assessed following SRF inhibition, demonstrating that SRF inhibition is more effective than AR inhibition in castrate-resistant cells. Our data support SRF as a promising therapeutic target in combination with current treatments. © 2015 Wiley Periodicals, Inc.

  3. 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...

  4. Design, synthesis, and in vivo SAR of a novel series of pyrazolines as potent selective androgen receptor modulators.

    Science.gov (United States)

    Zhang, Xuqing; Li, Xiaojie; Allan, George F; Sbriscia, Tifanie; Linton, Olivia; Lundeen, Scott G; Sui, Zhihua

    2007-08-09

    A novel series of pyrazolines 2 have been designed, synthesized, and evaluated by in vivo screening as tissue-selective androgen receptor modulators (SARMs). Structure-activity relationships (SAR) were investigated at the R1 to R6 positions as well as the core pyrazoline ring and the anilide linker. Overall, strong electron-withdrawing groups at the R1 and R2 positions and a small group at the R5 and R6 position are optimal for AR agonist activity. The (S)-isomer of 7c exhibits more potent AR agonist activity than the corresponding (R)-isomer. (S)-7c exhibited an overall partial androgenic effect but full anabolic effect via oral administration in castrated rats. It demonstrated a noticeable antiandrogenic effect on prostate in intact rats with endogenous testosterone. Thus, (S)-7c is a tissue-selective nonsteroidal androgen receptor modulator with agonist activity on muscle and mixed agonist and antagonist activity on prostate.

  5. Prostate cancer characteristics associated with response to pre-receptor targeting of the androgen axis.

    Directory of Open Access Journals (Sweden)

    Elahe A Mostaghel

    Full Text Available Factors influencing differential responses of prostate tumors to androgen receptor (AR axis-directed therapeutics are poorly understood, and predictors of treatment efficacy are needed. We hypothesized that the efficacy of inhibiting DHT ligand synthesis would associate with intra-tumoral androgen ratios indicative of relative dependence on DHT-mediated growth.We characterized two androgen-sensitive prostate cancer xenograft models after androgen suppression by castration in combination with the SRD5A inhibitor, dutasteride, as well as a panel of castration resistant metastases obtained via rapid autopsy.In LuCaP35 tumors (intra-tumoral T:DHT ratio 2:1 dutasteride suppressed DHT to 0.02 ng/gm and prolonged survival vs. castration alone (337 vs.152 days, HR 2.8, p = 0.0015. In LuCaP96 tumors (T:DHT 10:1, survival was not improved despite similar DHT reduction (0.02 ng/gm. LuCaP35 demonstrated higher expression of steroid biosynthetic enzymes maintaining DHT levels (5-fold higher SRD5A1, 41 fold higher, 99-fold higher RL-HSD, p<0.0001 for both, reconstitution of intra-tumoral DHT (to ∼30% of untreated tumors, and ∼2 fold increased expression of full length AR. In contrast, LuCaP96 demonstrated higher levels of steroid catabolizing enzymes (6.9-fold higher AKR1C2, 3000-fold higher UGT2B15, p = 0.002 and p<0.0001 respectively, persistent suppression of intra-tumoral DHT, and 6-8 fold induction of full length AR and the ligand independent V7 AR splice variant. Human metastases demonstrated bio-active androgen levels and AR full length and AR splice-variant expression consistent with the range observed in xenografts.Intrinsic differences in basal steroidogenesis, as well as variable expression of full length and splice-variant AR, associate with response and resistance to pre-receptor AR ligand suppression. Expression of steroidogenic enzymes and AR isoforms may serve as potential biomarkers of sensitivity to potent AR-axis inhibition and

  6. Effects of alcohol feeding on androgen receptors in the rat pituitary gland

    International Nuclear Information System (INIS)

    Chung, K.W.

    1987-01-01

    Specific binding of testosterone-1β,2β- 3 H by cytosol from anterior pituitary gland of ethanol-fed, isocaloric control, and castrated control and ethanol-fed rats with or without testosterone treatment has been investigated by charcoal assay. The number of androgen binding sites was significantly reduced in alcohol-fed rats when compared to the isocaloric control value, with no significant change in Kd. Castration significantly increased the number of receptor sites in control rats and when castrated control animals were treated with testosterone the binding sites were decreased to the intact control level. In contrast, castration or testosterone given to castrated alcohol-fed rats did not alter alcohol-induced reduction of the receptor sites. The binding affinity (Kd) is identical in all groups. The concentration of serum luteinizing hormone (LH) was significantly lower in alcohol-fed rats when compared to that of normal controls. An increased serum LH level with a decreased testosterone level was noted in castrated control rats. However, castration of alcohol-fed rats had little or no effects on the concentrations of LH and testosterone. Administration of testosterone suppressed castration-induced high LH in control rats but alcohol induced reduction of LH level was not altered by this treatment. These findings indicate that alcohol exerts a suppressive effect on the content of androgen receptors and secretory functions of gonadotropins in the pituitary gland. 23 references, 1 figure, 1 table

  7. ZINC-INDUCED EGF RECEPTOR SIGNALING REQUIRES SRC-MEDIATED PHOSPHORYLATION OF THE EGF RECEPTOR ON TYROSINE 845 (Y845)

    Science.gov (United States)

    ZINC-INDUCED EGF RECEPTOR SIGNALING REQUIRES Src-MEDIATED PHOSPHORYLATION OF THE EGF RECEPTOR ON TYROSINE 845 (Y845)Weidong Wu1, Lee M. Graves2, Gordon N. Gill3 and James M. Samet4 1Center for Environmental Medicine and Lung Biology; 2Department of Pharmacology, University o...

  8. Pituitary Androgen Receptor Signalling Regulates Prolactin but Not Gonadotrophins in the Male Mouse

    Science.gov (United States)

    O’Hara, Laura; Curley, Michael; Tedim Ferreira, Maria; Cruickshanks, Lyndsey; Milne, Laura; Smith, Lee B.

    2015-01-01

    Production of the androgen testosterone is controlled by a negative feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. Stimulation of testicular Leydig cells by pituitary luteinising hormone (LH) is under the control of hypothalamic gonadotrophin releasing hormone (GnRH), while suppression of LH secretion by the pituitary is controlled by circulating testosterone. Exactly how androgens exert their feedback control of gonadotrophin secretion (and whether this is at the level of the pituitary), as well as the role of AR in other pituitary cell types remains unclear. To investigate these questions, we exploited a transgenic mouse line (Foxg1Cre/+; ARfl/y) which lacks androgen receptor in the pituitary gland. Both circulating testosterone and gonadotrophins are unchanged in adulthood, demonstrating that AR signalling is dispensable in the male mouse pituitary for testosterone-dependent regulation of LH secretion. In contrast, Foxg1Cre/+; ARfl/y males have a significant increase in circulating prolactin, suggesting that, rather than controlling gonadotrophins, AR-signalling in the pituitary acts to suppress aberrant prolactin production in males. PMID:25799562

  9. The ErbB family and androgen receptor signaling are targets of Celecoxib in prostate cancer.

    Science.gov (United States)

    Brizzolara, Antonella; Benelli, Roberto; Venè, Roberta; Barboro, Paola; Poggi, Alessandro; Tosetti, Francesca; Ferrari, Nicoletta

    2017-08-01

    Inflammation plays a central role in prostate cancer (PCa) development through significant crosstalk between the COX-2-ErbB family receptor network and androgen receptor (AR)-EGFR signaling pathways. The purpose of this work was to determine the ability of the COX-2 inhibitor Celecoxib to modulate the EGFR-AR signaling pathway in androgen-dependent PCa cells and to provide a rationale for its beneficial use in chemopreventive strategies. Functional studies of Celecoxib activity were performed on LNCaP prostate cancer cells. Western blotting, gene expression analysis, dual-luciferase reporter assay and ELISA were applied to assess the Celecoxib mechanisms of action. We found that Celecoxib, through EGF and amphiregulin (AREG) induction, caused EGFR and ErbB2 activation and consequent degradation associated with the inhibition of androgenic signaling. By upregulating the E3 ubiquitin ligase Nrdp1, Celecoxib also efficiently downregulated ErbB3, which is strongly implicated in castration-resistant prostate cancer. Lastly, Celecoxib directly regulated AR transcription and translation independent of ErbB activation by downregulating the RNA binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K). The simultaneous suppression of ErbB kinases and androgen signaling by Celecoxib represents a novel strategy to interrupt the vicious cycle of AR/ErbB cross-talk with the primary purpose of undermining their resilient signaling in prostate cancer progression. Our data provide important premises for the chemopreventive use of Celecoxib in the clinical management of prostate cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Genotype and phenotype in Klinefelter syndrome - impact of androgen receptor polymorphism and skewed X inactivation

    DEFF Research Database (Denmark)

    Bojesen, A; Hertz, J M; Gravholt, C H

    2011-01-01

    The phenotypic variation of Klinefelter syndrome (KS) is wide and may by caused by various genetic and epigenetic effects. Skewed inactivation of the supra-numerical X chromosome and polymorphism in the androgen receptor (AR) have been suggested as plausible causes. We wanted to describe X...

  11. Androgen responsiveness of the new human endometrial cancer cell line MFE-296.

    Science.gov (United States)

    Hackenberg, R; Beck, S; Filmer, A; Hushmand Nia, A; Kunzmann, R; Koch, M; Slater, E P; Schulz, K D

    1994-04-01

    MFE-296 endometrial cancer cells express androgen receptors in vitro. These cells, which are tumorigenic in nude mice, are derived from a moderately differentiated human endometrial adenocarcinoma. They express vimentin and the cytokeratins 7, 8, 18, and 19. Karyotyping revealed near-tetraploidy for most of the cells. No marker chromosomes were observed. DNA analyses confirmed the genetic identity of the cell line and the patient from whom the cell line was derived. Proliferation of MFE-296 cells was inhibited by the progestin R5020 and the androgen dihydrotestosterone (DHT). The inhibition of proliferation by DHT was antagonized by the antiandrogen Casodex, demonstrating the involvement of the androgen receptor. Androgen binding was determined at 22,000 binding sites per cell using a whole-cell assay (KD = 0.05 nM) and 30 fmol/mg protein with the dextran charcoal method; 7 fmol/mg protein of progesterone receptors were found, whereas estrogen receptors were below 5 fmol/mg protein. The androgen receptor was functionally intact, as demonstrated by transfection experiments with a reporter-gene construct, containing an androgen-responsive element. In MFE-296 cells the content of the androgen receptor was up-regulated by its own ligand.

  12. Androgen Signaling Disruption during Fetal and Postnatal Development Affects Androgen Receptor and Connexin 43 Expression and Distribution in Adult Boar Prostate

    Directory of Open Access Journals (Sweden)

    Anna Hejmej

    2013-01-01

    Full Text Available To date, limited knowledge exists regarding the role of the androgen signaling during specific periods of development in the regulation of androgen receptor (AR and connexin 43 (Cx43 in adult prostate. Therefore, in this study we examined mRNA and protein expression, and tissue distribution of AR and Cx43 in adult boar prostates following fetal (GD20, neonatal (PD2, and prepubertal (PD90 exposure to an antiandrogen flutamide (50 mg/kg bw. In GD20 and PD2 males we found the reduction of the luminal compartment, inflammatory changes, decreased AR and increased Cx43 expression, and altered localization of both proteins. Moreover, enhanced apoptosis and reduced proliferation were detected in the prostates of these animals. In PD90 males the alterations were less evident, except that Cx43 expression was markedly upregulated. The results presented herein indicate that in boar androgen action during early fetal and neonatal periods plays a key role in the maintenance of normal phenotype and functions of prostatic cells at adulthood. Furthermore, we demonstrated that modulation of Cx43 expression in the prostate could serve as a sensitive marker of hormonal disruption during different developmental stages.

  13. Prognostic value of androgen receptor level in breast tumors

    International Nuclear Information System (INIS)

    Gershtejn, E.S.; Smirnova, K.D.; Vishnyakova, V.V.; Ermilova, V.D.

    1988-01-01

    Androgen receptor (AR) level was studied in 254 untreated cases of breast cancer. The occurrence and mean level of AR did not depend upon stage of disease or reproductive status. Increase in degree of anaplasia of ductal-invasive carcinoma was matched by decrease in its AR-positive fraction from 75 to 20 %. Recurence-free survival in surgically treated p T 1-2 No Mo patients did not depend upon AR status of tumor. In cases of p T 1-2 Nd Mo AR-positive malignancy, recurrences or metastases occurred 2.2 times as rarely when surgery was followed by the best results were obtained with postoperative chemo- and chemoradiation treatment

  14. The transcriptional programme of the androgen receptor (AR) in prostate cancer.

    Science.gov (United States)

    Lamb, Alastair D; Massie, Charlie E; Neal, David E

    2014-03-01

    The androgen receptor (AR) is essential for normal prostate and prostate cancer cell growth. AR transcriptional activity is almost always maintained even in hormone relapsed prostate cancer (HRPC) in the absence of normal levels of circulating testosterone. Current molecular techniques, such as chromatin-immunoprecipitation sequencing (ChIP-seq), have permitted identification of direct AR-binding sites in cell lines and human tissue with a distinct coordinate network evident in HRPC. The effectiveness of novel agents, such as abiraterone acetate (suppresses adrenal androgens) or enzalutamide (MDV3100, potent AR antagonist), in treating advanced prostate cancer underlines the on-going critical role of the AR throughout all stages of the disease. Persistent AR activity in advanced disease regulates cell cycle activity, steroid biosynthesis and anabolic metabolism in conjunction with regulatory co-factors, such as the E2F family, c-Myc and signal transducer and activator of transcription (STAT) transcription factors. Further treatment approaches must target these other factors. © 2013 The Authors. BJU International © 2013 BJU International.

  15. Androgen Receptor Deregulation Drives Bromodomain-Mediated Chromatin Alterations in Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Alfonso Urbanucci

    2017-06-01

    Full Text Available Global changes in chromatin accessibility may drive cancer progression by reprogramming transcription factor (TF binding. In addition, histone acetylation readers such as bromodomain-containing protein 4 (BRD4 have been shown to associate with these TFs and contribute to aggressive cancers including prostate cancer (PC. Here, we show that chromatin accessibility defines castration-resistant prostate cancer (CRPC. We show that the deregulation of androgen receptor (AR expression is a driver of chromatin relaxation and that AR/androgen-regulated bromodomain-containing proteins (BRDs mediate this effect. We also report that BRDs are overexpressed in CRPCs and that ATAD2 and BRD2 have prognostic value. Finally, we developed gene stratification signature (BROMO-10 for bromodomain response and PC prognostication, to inform current and future trials with drugs targeting these processes. Our findings provide a compelling rational for combination therapy targeting bromodomains in selected patients in which BRD-mediated TF binding is enhanced or modified as cancer progresses.

  16. CAG repeat testing of androgen receptor polymorphism: is this necessary for the best clinical management of hypogonadism?

    Science.gov (United States)

    Francomano, Davide; Greco, Emanuela A; Lenzi, Andrea; Aversa, Antonio

    2013-10-01

    It is controversial whether or not testing the length of the androgen receptor polymorphism in clinical practice is useful for correct diagnosis and treatment of hypogonadism. To describe the molecular and clinical implications of testing the length of the androgen receptor polymorphism for treatment of hypogonadism in both male and female subjects. A systematic Medline search was conducted using several terms related to and including the terms "androgen receptor," "CAG-repeat polymorphism," "male hypogonadism," "female hypogonadism," and "neurodegenerative disease." Clinical evidence that demonstrates the importance of CAG repeat number investigation in male and female hypogonadism. A thorough review of the clinical utility of CAG repeat polymorphism investigation in men and women with hypogonadism is presented. The role of AR CAG repeat number investigation in hypogonadism (male and female) is not yet established in the clinical practice. In both sexes, a role during clinical management of hormonal replacement therapies may be hypothesized, but the CAG repeat number's relationship with the presence or absence of hypogonadal symptoms remains unclear. Pharmacogenomic investigations of the AR polymorphism may be a future option to tailor testosterone titration individually and to better identify subjects as potentially more or less responsive to treatments; also, investigation may be important to individually predict beneficial and side effects in special subpopulations, specifically, obese men and postmenopausal women. © 2013 International Society for Sexual Medicine.

  17. Assessment of endocrine disruption potential of essential oils of culinary herbs and spices involving glucocorticoid, androgen and vitamin D receptors.

    Science.gov (United States)

    Bartoňková, Iveta; Dvořák, Zdeněk

    2018-04-25

    Essential oils (EOs) of culinary herbs and spices are consumed on a daily basis. They are multicomponent mixtures of compounds with already demonstrated biological activities. Taking into account regular dietary intake and the chemical composition of EOs, they may be considered as candidates for endocrine-disrupting entities. Therefore, we examined the effects of 31 EOs of culinary herbs and spices on transcriptional activities of glucocorticoid receptor (GR), androgen receptor (AR) and vitamin D receptor (VDR). Using reporter gene assays in stably transfected cell lines, weak anti-androgen and anti-glucocorticoid activity was observed for EO of vanilla and nutmeg, respectively. Moderate augmentation of calcitriol-dependent VDR activity was caused by EOs of ginger, thyme, coriander and lemongrass. Mixed anti-glucocorticoid and VDR-stimulatory activities were displayed by EOs of turmeric, oregano, dill, caraway, verveine and spearmint. The remaining 19 EOs were inactive against all receptors under investigation. Analyses of GR, AR and VDR target genes by means of RT-PCR confirmed the VDR-stimulatory effects, but could not confirm the anti-glucocorticoid and anti-androgen effects of EOs. In conclusion, although we observed minor effects of several EOs on transcriptional activities of GR, AR and VDR, the toxicological significance of these effects is very low. Hence, 31 EOs of culinary herbs and spices may be considered safe, in terms of endocrine disruption involving receptors GR, AR and VDR.

  18. Intrahippocampal administration of an androgen receptor antagonist, flutamide, can increase anxiety-like behavior in intact and DHT-replaced male rats.

    Science.gov (United States)

    Edinger, Kassandra L; Frye, Cheryl A

    2006-08-01

    Testosterone (T) and its 5alpha-reduced metabolite, dihydrotestosterone (DHT), can decrease anxiety-like behavior; however, the mechanisms underlying these effects have not been established. First, we hypothesized that if T reduces anxiety-like behavior through actions of its 5alpha-reduced metabolite, DHT, then gonadectomy (GDX) would increase anxiety-like behavior, an effect which would be reversed by systemic administration of DHT. Second, we hypothesized that if T and DHT reduce anxiety-like behavior in part through actions at intracellular androgen receptors in the hippocampus, then administration of an androgen receptor antagonist, flutamide, directly to the hippocampus should increase anxiety-like behavior of intact and DHT-replaced, but not GDX, male rats. Inserts that were empty or contained flutamide were applied directly to the dorsal hippocampus of intact, GDX, or GDX and DHT-replaced rats 2 h prior to testing in the open field, elevated plus maze, or defensive freezing tasks. GDX rats exhibited significantly more anxiety-like behaviors than intact or DHT-replaced rats. Intact and DHT-replaced rats administered flutamide to the hippocampus showed significantly more anxiety-like behavior than did intact and DHT-replaced controls. However, flutamide alone did not increase anxiety-like behavior of GDX rats. Together, these findings suggest that androgens can decrease anxiety-like behavior of male rats in part through DHT's actions at androgen receptors in the hippocampus.

  19. Differential Effects of Leptin on the Invasive Potential of Androgen-Dependent and -Independent Prostate Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Dayanand D. Deo

    2008-01-01

    Full Text Available Obesity has been linked with an increased risk of prostate cancer. The formation of toxic free oxygen radicals has been implicated in obesity mediated disease processes. Leptin is one of the major cytokines produced by adipocytes and controls body weight homeostasis through food intake and energy expenditure. The rationale of the study was to determine the impact of leptin on the metastatic potential of androgen-sensitive (LNCaP cells as well as androgen-insensitive (PC-3 and DU-145 cells. At a concentration of 200_nm, LNCaP cells showed a significant increase (20% above control; P<.0001 in cellular proliferation without any effect on androgen-insensitive cells. Furthermore, exposure to leptin caused a significant (P<.01 to P<.0001 dose-dependent decrease in migration and invasion of PC3 and Du-145 prostate carcinoma cell lines. At the molecular level, exposure of androgen-independent prostate cancer cells to leptin stimulates the phosphorylation of MAPK at early time point as well as the transcription factor STAT3, suggesting the activation of the intracellular signaling cascade upon leptin binding to its cognate receptor. Taken together, these results suggest that leptin mediates the invasive potential of prostate carcinoma cells, and that this effect is dependent on their androgen sensitivity.

  20. Noradrenaline, oxymetazoline and phorbol myristate acetate induce distinct functional actions and phosphorylation patterns of α1A-adrenergic receptors.

    Science.gov (United States)

    Alcántara-Hernández, Rocío; Hernández-Méndez, Aurelio; Romero-Ávila, M Teresa; Alfonzo-Méndez, Marco A; Pupo, André S; García-Sáinz, J Adolfo

    2017-12-01

    In LNCaP cells that stably express α 1A -adrenergic receptors, oxymetazoline increased intracellular calcium and receptor phosphorylation, however, this agonist was a weak partial agonist, as compared to noradrenaline, for calcium signaling. Interestingly, oxymetazoline-induced receptor internalization and desensitization displayed greater effects than those induced by noradrenaline. Phorbol myristate acetate induced modest receptor internalization and minimal desensitization. α 1A -Adrenergic receptor interaction with β-arrestins (colocalization/coimmunoprecipitation) was induced by noradrenaline and oxymetazoline and, to a lesser extent, by phorbol myristate acetate. Oxymetazoline was more potent and effective than noradrenaline in inducing ERK 1/2 phosphorylation. Mass spectrometric analysis of immunopurified α 1A -adrenergic receptors from cells treated with adrenergic agonists and the phorbol ester clearly showed that phosphorylated residues were present both at the third intracellular loop and at the carboxyl tail. Distinct phosphorylation patterns were observed under the different conditions. The phosphorylated residues were: a) Baseline and all treatments: T233; b) noradrenaline: S220, S227, S229, S246, S250, S389; c) oxymetazoline: S227, S246, S381, T384, S389; and d) phorbol myristate acetate: S246, S250, S258, S351, S352, S401, S402, S407, T411, S413, T451. Our novel data, describing the α 1A -AR phosphorylation sites, suggest that the observed different phosphorylation patterns may participate in defining adrenoceptor localization and action, under the different conditions examined. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Key structural features of nonsteroidal ligands for binding and activation of the androgen receptor.

    Science.gov (United States)

    Yin, Donghua; He, Yali; Perera, Minoli A; Hong, Seoung Soo; Marhefka, Craig; Stourman, Nina; Kirkovsky, Leonid; Miller, Duane D; Dalton, James T

    2003-01-01

    The purposes of the present studies were to examine the androgen receptor (AR) binding ability and in vitro functional activity of multiple series of nonsteroidal compounds derived from known antiandrogen pharmacophores and to investigate the structure-activity relationships (SARs) of these nonsteroidal compounds. The AR binding properties of sixty-five nonsteroidal compounds were assessed by a radioligand competitive binding assay with the use of cytosolic AR prepared from rat prostates. The AR agonist and antagonist activities of high-affinity ligands were determined by the ability of the ligand to regulate AR-mediated transcriptional activation in cultured CV-1 cells, using a cotransfection assay. Nonsteroidal compounds with diverse structural features demonstrated a wide range of binding affinity for the AR. Ten compounds, mainly from the bicalutamide-related series, showed a binding affinity superior to the structural pharmacophore from which they were derived. Several SARs regarding nonsteroidal AR binding were revealed from the binding data, including stereoisomeric conformation, steric effect, and electronic effect. The functional activity of high-affinity ligands ranged from antagonist to full agonist for the AR. Several structural features were found to be determinative of agonist and antagonist activities. The nonsteroidal AR agonists identified from the present studies provided a pool of candidates for further development of selective androgen receptor modulators (SARMs) for androgen therapy. Also, these studies uncovered or confirmed numerous important SARs governing AR binding and functional properties by nonsteroidal molecules, which would be valuable in the future structural optimization of SARMs.

  2. BTG2 is an LXXLL-dependent co-repressor for androgen receptor transcriptional activity

    International Nuclear Information System (INIS)

    Hu, Xu-Dong; Meng, Qing-Hui; Xu, Jia-Ying; Jiao, Yang; Ge, Chun-Min; Jacob, Asha; Wang, Ping; Rosen, Eliot M; Fan, Saijun

    2011-01-01

    Research highlights: → BTG2 associates with AR, androgen causes an increase of the interaction. → BTG2 as a co-repressor inhibits the AR-mediated transcription activity. → BTG2 inhibits the transcription activity and expression of PSA. → An intact 92 LxxLL 96 motif is essential and necessary for these activities of BTG2, while the 20 LxxLL 24 motif is not required. → Ectopic expression of BTG2 reduces proliferation of prostate cancer cells. -- Abstract: The tumor suppressor gene, BTG2 has been down-regulated in prostate cancer and the ectopic expression of this gene has been shown to inhibit prostate cancer cell growth. Sequence analysis revealed that the BTG2 protein contains two leucine-rich motifs ( 20 LxxLL 24 and 92 LxxLL 96 ), which are usually found in nuclear receptor co-factors. Based on this, we postulated that there will be an association between BTG2 and AR. In this study, we discovered that BTG2 directly bound to the androgen receptor (AR) in the absence of 5α-dihydrotestosterone (DHT), and in the presence of the androgen, this interaction was increased. BTG2 bearing the mutant 20 LxxLL 24 motif bound to AR equally efficient as the wild-type BTG2, while BTG2 bearing the mutant 92 LxxLL 96 motif failed to interact with AR. Functional studies indicated that ectopic expression of BTG2 caused a significant inhibition of AR-mediated transcriptional activity and a decreased growth of prostate cancer cells. Androgen-induced promoter activation and expression of prostate-specific antigen (PSA) are significantly attenuated by BTG2. The intact 92 LxxLL 96 motif is required for these activities. These findings, for the first time, demonstrate that BTG2 complexes with AR via an LxxLL-dependent mechanism and may play a role in prostate cancer via modulating the AR signaling pathway.

  3. BTG2 is an LXXLL-dependent co-repressor for androgen receptor transcriptional activity

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xu-Dong [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou 215123 (China); Meng, Qing-Hui [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057 (United States); Xu, Jia-Ying; Jiao, Yang [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou 215123 (China); Ge, Chun-Min [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057 (United States); Jacob, Asha; Wang, Ping [North Shore University Hospital-Long Island Jewish Medical Center and The Feinstein Institute for Medical Research, Manhasset, NY 11030 (United States); Rosen, Eliot M [Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20057 (United States); Fan, Saijun, E-mail: sjfan@suda.edu.cn [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou 215123 (China)

    2011-01-28

    Research highlights: {yields} BTG2 associates with AR, androgen causes an increase of the interaction. {yields} BTG2 as a co-repressor inhibits the AR-mediated transcription activity. {yields} BTG2 inhibits the transcription activity and expression of PSA. {yields} An intact {sup 92}LxxLL{sup 96} motif is essential and necessary for these activities of BTG2, while the {sup 20}LxxLL{sup 24} motif is not required. {yields} Ectopic expression of BTG2 reduces proliferation of prostate cancer cells. -- Abstract: The tumor suppressor gene, BTG2 has been down-regulated in prostate cancer and the ectopic expression of this gene has been shown to inhibit prostate cancer cell growth. Sequence analysis revealed that the BTG2 protein contains two leucine-rich motifs ({sup 20}LxxLL{sup 24} and {sup 92}LxxLL{sup 96}), which are usually found in nuclear receptor co-factors. Based on this, we postulated that there will be an association between BTG2 and AR. In this study, we discovered that BTG2 directly bound to the androgen receptor (AR) in the absence of 5{alpha}-dihydrotestosterone (DHT), and in the presence of the androgen, this interaction was increased. BTG2 bearing the mutant {sup 20}LxxLL{sup 24} motif bound to AR equally efficient as the wild-type BTG2, while BTG2 bearing the mutant {sup 92}LxxLL{sup 96} motif failed to interact with AR. Functional studies indicated that ectopic expression of BTG2 caused a significant inhibition of AR-mediated transcriptional activity and a decreased growth of prostate cancer cells. Androgen-induced promoter activation and expression of prostate-specific antigen (PSA) are significantly attenuated by BTG2. The intact {sup 92}LxxLL{sup 96} motif is required for these activities. These findings, for the first time, demonstrate that BTG2 complexes with AR via an LxxLL-dependent mechanism and may play a role in prostate cancer via modulating the AR signaling pathway.

  4. 5alphaDH-DOC (5alpha-dihydro-deoxycorticosterone) activates androgen receptor in castration-resistant prostate cancer.

    Science.gov (United States)

    Uemura, Motohide; Honma, Seijiro; Chung, Suyoun; Takata, Ryo; Furihata, Mutsuo; Nishimura, Kazuo; Nonomura, Norio; Nasu, Yasutomo; Miki, Tsuneharu; Shuin, Taro; Fujioka, Tomoaki; Okuyama, Akihiko; Nakamura, Yusuke; Nakagawa, Hidewaki

    2010-08-01

    Prostate cancer often relapses during androgen-depletion therapy, even under the castration condition in which circulating androgens are drastically reduced. High expressions of androgen receptor (AR) and genes involved in androgen metabolism indicate a continued role for AR in castration-resistant prostate cancers (CRPCs). There is increasing evidence that some amounts of 5alpha-dihydrotestosterone (DHT) and other androgens are present sufficiently to activate AR within CRPC tissues, and enzymes involved in the androgen and steroid metabolism, such as 5alpha-steroid reductases, are activated in CRPCs. In this report, we screened eight natural 5alphaDH-steroids to search for novel products of 5alpha-steroid reductases, and identified 11-deoxycorticosterone (DOC) as a novel substrate for 5alpha-steroid reductases in CRPCs. 11-Deoxycorticosterone (DOC) and 5alpha-dihydro-deoxycorticosterone (5alphaDH-DOC) could promote prostate cancer cell proliferation through AR activation, and type 1 5alpha-steroid reductase (SRD5A1) could convert from DOC to 5alphaDH-DOC. Sensitive liquid chromatography-tandem mass spectrometric analysis detected 5alphaDH-DOC in some clinical CRPC tissues. These findings implicated that under an extremely low level of DHT, 5alphaDH-DOC and other products of 5alpha-steroid reductases within CRPC tissues might activate the AR pathway for prostate cancer cell proliferation and survival under castration.

  5. Targeting the androgen receptor pathway in castration-resistant prostate cancer: progresses and prospects

    Science.gov (United States)

    Ferraldeschi, R; Welti, J; Luo, J; Attard, G; de Bono, JS

    2015-01-01

    Androgen receptor (AR) signaling is a critical pathway for prostate cancer cells, and androgen-deprivation therapy (ADT) remains the principal treatment for patients with locally advanced and metastatic disease. However, over time, most tumors become resistant to ADT. The view of castration-resistant prostate cancer (CRPC) has changed dramatically in the last several years. Progress in understanding the disease biology and mechanisms of castration resistance led to significant advancements and to paradigm shift in the treatment. Accumulating evidence showed that prostate cancers develop adaptive mechanisms for maintaining AR signaling to allow for survival and further evolution. The aim of this review is to summarize molecular mechanisms of castration resistance and provide an update in the development of novel agents and strategies to more effectively target the AR signaling pathway. PMID:24837363

  6. Selective androgen receptor modulators for the treatment of late onset male hypogonadism.

    Science.gov (United States)

    Coss, Christopher C; Jones, Amanda; Hancock, Michael L; Steiner, Mitchell S; Dalton, James T

    2014-01-01

    Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators (SARMs) have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defi ned clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

  7. Selective androgen receptor modulators for the treatment of late onset male hypogonadism

    Directory of Open Access Journals (Sweden)

    Christopher C Coss

    2014-04-01

    Full Text Available Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators (SARMs have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defi ned clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

  8. Selective androgen receptor modulators for the treatment of late onset male hypogonadism

    Science.gov (United States)

    Coss, Christopher C; Jones, Amanda; Hancock, Michael L; Steiner, Mitchell S; Dalton, James T

    2014-01-01

    Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators (SARMs) have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defined clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism. PMID:24407183

  9. Reproductive phase dependent daily variation in melatonin receptors (Mel(1a) and Mel(1b)), androgen receptor (AR) and lung associated immunity of Perdicula asiatica.

    Science.gov (United States)

    Kharwar, R K; Haldar, C

    2011-06-01

    Our knowledge about the involvement of melatonin in the regulation of lung associated immune system (LAIS) is still poor though the melatonin receptor types (Mel(1a) and Mel(1b)) have been localized in lungs of some wild birds. We thought to explore the correlation between daily variation (within a 24h time scale) in peripheral melatonin and testosterone along with expression of melatonin receptors (Mel(1a) and Mel(1b)) and androgen receptor (AR) in lungs during reproductively active and inactive phases. Receptor expression of Mel(1b) was more prominent than Mel(1a) at all the time points during both the reproductive phases. The expression of AR was inversely related to both the melatonin and its receptor expression at the 24h time scale during both the reproductive phases. Results also reflected a parallel relationship of melatonin, melatonin receptors and all the immune parameters (total leukocyte count, lymphocyte count, % stimulation ratio) suggesting that peripheral melatonin might be responsible for daily periodicity of LAIS. The presence of androgen receptors in lung led us to propose that gonadal steroid does influence the LAIS. Therefore melatonin along with testosterone might be acting as a temporal synchronizer for daily rhythms in lung associated immunity in Perdicula asiatica during different reproductive phases. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Saw Palmetto induces growth arrest and apoptosis of androgen-dependent prostate cancer LNCaP cells via inactivation of STAT 3 and androgen receptor signaling.

    Science.gov (United States)

    Yang, Yang; Ikezoe, Takayuki; Zheng, Zhixing; Taguchi, Hirokuni; Koeffler, H Phillip; Zhu, Wei-Guo

    2007-09-01

    PC-SPES is an eight-herb mixture that has an activity against prostate cancer. Recently, we purified Saw Palmetto (Serenoa repens) from PC-SPES and found that Saw Palmetto induced growth arrest of prostate cancer LNCaP, DU145, and PC3 cells with ED50s of approximately 2.0, 2.6, and 3.3 microl/ml, respectively, as measured by mitochondrial-dependent conversion of the the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Saw Palmetto induced apoptosis of LNCaP cells in a time- and dose-dependent manner as measured by TUNEL assays. Also, Saw Palmetto increased the expression of p21waf1 and p53 protein in LNCaP cells. In addition, we found that Saw Palmetto down-regulated DHT- or IL-6-induced expression of prostate specific antigen in conjunction with down-regulation of the level of androgen receptor in the nucleus as measured by Western blot analysis. Moreover, Saw Palmetto down-regulated the IL-6-induced level of the phosphorylated form of STAT 3 in LNCaP cells. Furthermore, Saw Palmetto inhibited the growth of LNCaP cells present as tumor xenografts in BALB/c nude mice without adverse effect. These results indicate that Saw Palmetto might be useful for the treatment of individuals with prostate cancer.

  11. A novel inducible transactivation domain in the androgen receptor: implications for PRK in prostate cancer

    OpenAIRE

    Metzger, Eric; Müller, Judith M.; Ferrari, Stefano; Buettner, Reinhard; Schüle, Roland

    2003-01-01

    In addition to the classical activation by ligands, nuclear receptor activity is also regulated by ligand-independent signalling. Here, we unravel a novel signal transduction pathway that links the RhoA effector protein kinase C-related kinase PRK1 to the transcriptional activation of the androgen receptor (AR). Stimulation of the PRK signalling cascade results in a ligand-dependent superactivation of AR. We show that AR and PRK1 interact both in vivo and in vitro. The transactivation unit 5 ...

  12. TBECH, 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane, alters androgen receptor regulation in response to mutations associated with prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kharlyngdoh, Joubert Banjop; Asnake, Solomon; Pradhan, Ajay; Olsson, Per-Erik, E-mail: per-erik.olsson@oru.se

    2016-09-15

    Point mutations in the AR ligand-binding domain (LBD) can result in altered AR structures leading to changes of ligand specificity and functions. AR mutations associated to prostate cancer (PCa) have been shown to result in receptor activation by non-androgenic substances and anti-androgenic drugs. Two AR mutations known to alter the function of anti-androgens are the AR{sub T877A} mutation, which is frequently detected mutation in PCa tumors and the AR{sub W741C} that is rare and has been derived in vitro following exposure of cells to the anti-androgen bicalutamide. AR activation by non-androgenic environmental substances has been suggested to affect PCa progression. In the present study we investigated the effect of AR mutations (AR{sub W741C} and AR{sub T877A}) on the transcriptional activation following exposure of cells to an androgenic brominated flame retardant, 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH, also named DBE-DBCH). The AR mutations resulted in higher interaction energies and increased transcriptional activation in response to TBECH diastereomer exposures. The AR{sub T877A} mutation rendered AR highly responsive to low levels of DHT and TBECH and led to increased AR nuclear translocation. Gene expression analysis showed a stronger induction of AR target genes in LNCaP cells (AR{sub T877A}) compared to T-47D cells (AR{sub WT}) following TBECH exposure. Furthermore, AR knockdown experiments confirmed the AR dependency of these responses. The higher sensitivity of AR{sub T877A} and AR{sub W741C} to low levels of TBECH suggests that cells with these AR mutations are more susceptible to androgenic endocrine disrupters. - Highlights: • TBECH, is an endocrine disrupting compound that differ in activity depending on AR structure and sequence. • TBECH interaction with the human AR-LBD containing the mutations W741C and T877A is increased compared to the wild type receptor • The mutations, W741C and T877A, are more potent than the wild type

  13. Phosphorylation of the dimeric cytoplasmic domain of the phytosulfokine receptor, PSKR1

    KAUST Repository

    Muleya, V.

    2016-08-04

    Phytosulfokines (PSKs) are plant peptide hormones that co-regulate plant growth, differentiation and defense responses. PSKs signal through a plasma membrane localized leucine-rich repeat receptor-like kinase (phytosulfokine receptor 1, PSKR1) that also contains a functional cytosolic guanylate cyclase with its cyclase catalytic center embedded within the kinase domain. To functionally characterize this novel type of overlapping dual catalytic function, we investigated the phosphorylation of PSKR1 in vitro Tandem mass spectrometry of the cytoplasmic domain of PSKR1 (PSKR1cd) revealed at least 11 phosphorylation sites (8 serines, 2 threonines and 1 tyrosine) within the PSKR1cd. Phosphomimetic mutations of three serine residues (Ser686, Ser696 and Ser698) in tandem at the juxta-membrane position resulted in enhanced kinase activity in the on-mutant that was suppressed in the off-mutant, but both mutations reduced guanylate cyclase activity. Both the on and off phosphomimetic mutations of the phosphotyrosine (Tyr888) residue in the activation loop suppressed kinase activity, while neither mutation affected guanylate cyclase activity. Size exclusion and analytical ultracentrifugation analysis of the PSKR1cd suggest that it is reversibly dimeric in solution, which was further confirmed by biflourescence complementation. Taken together, these data suggest that in this novel type of receptor domain architecture, specific phosphorylation and dimerization are possibly essential mechanisms for ligand-mediated catalysis and signaling.

  14. Phosphorylation of the dimeric cytoplasmic domain of the phytosulfokine receptor, PSKR1

    KAUST Repository

    Muleya, V.; Marondedze, Claudius; Wheeler, J. I.; Thomas, Ludivine; Mok, Y.-F.; Griffin, M. D. W.; Manallack, D. T.; Kwezi, L.; Lilley, K. S.; Gehring, Christoph A; Irving, H. R.

    2016-01-01

    Phytosulfokines (PSKs) are plant peptide hormones that co-regulate plant growth, differentiation and defense responses. PSKs signal through a plasma membrane localized leucine-rich repeat receptor-like kinase (phytosulfokine receptor 1, PSKR1) that also contains a functional cytosolic guanylate cyclase with its cyclase catalytic center embedded within the kinase domain. To functionally characterize this novel type of overlapping dual catalytic function, we investigated the phosphorylation of PSKR1 in vitro Tandem mass spectrometry of the cytoplasmic domain of PSKR1 (PSKR1cd) revealed at least 11 phosphorylation sites (8 serines, 2 threonines and 1 tyrosine) within the PSKR1cd. Phosphomimetic mutations of three serine residues (Ser686, Ser696 and Ser698) in tandem at the juxta-membrane position resulted in enhanced kinase activity in the on-mutant that was suppressed in the off-mutant, but both mutations reduced guanylate cyclase activity. Both the on and off phosphomimetic mutations of the phosphotyrosine (Tyr888) residue in the activation loop suppressed kinase activity, while neither mutation affected guanylate cyclase activity. Size exclusion and analytical ultracentrifugation analysis of the PSKR1cd suggest that it is reversibly dimeric in solution, which was further confirmed by biflourescence complementation. Taken together, these data suggest that in this novel type of receptor domain architecture, specific phosphorylation and dimerization are possibly essential mechanisms for ligand-mediated catalysis and signaling.

  15. A selective androgen receptor modulator with minimal prostate hypertrophic activity restores lean body mass in aged orchidectomized male rats.

    Science.gov (United States)

    Allan, George; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Ng, Raymond; Sui, Zhihua; Lundeen, Scott

    2008-06-01

    Androgens are required for the maintenance of normal sexual activity in adulthood and for enhancing muscle growth and lean body mass in adolescents and adults. Androgen receptor (AR) ligands with tissue selectivity (selective androgen receptor modulators, or SARMs) have potential for treating muscle wasting, hypogonadism of aging, osteoporosis, female sexual dysfunction, and other indications. JNJ-37654032 is a nonsteroidal AR ligand with mixed agonist and antagonist activity in androgen-responsive cell-based assays. It is an orally active SARM with muscle selectivity in orchidectomized rat models. It stimulated growth of the levator ani muscle with ED(50) 0.8 mg/kg, stimulating maximal growth at a dose of 3mg/kg. In contrast, it stimulated ventral prostate growth to 21% of its full size at 3mg/kg. At the same time, JNJ-37654032 reduced prostate weight in intact rats by 47% at 3mg/kg, while having no inhibitory effect on muscle. Using magnetic resonance imaging to monitor body composition, JNJ-37654032 restored about 20% of the lean body mass lost following orchidectomy in aged rats. JNJ-37654032 reduced follicle-stimulating hormone levels in orchidectomized rats and reduced testis size in intact rats. JNJ-37654032 is a potent prostate-sparing SARM with the potential for clinical benefit in muscle-wasting diseases.

  16. Androgen receptor signals regulate UDP-glucuronosyltransferases in the urinary bladder: a potential mechanism of androgen-induced bladder carcinogenesis.

    Science.gov (United States)

    Izumi, Koji; Zheng, Yichun; Hsu, Jong-Wei; Chang, Chawnshang; Miyamoto, Hiroshi

    2013-02-01

    UDP-glucuronosyltransferases (UGTs), major phase II drug metabolism enzymes, play an important role in urinary bladder cancer initiation by detoxifying carcinogens. We aimed to determine if androgens regulate UGT expression via the androgen receptor (AR) pathway in the bladder. Real-time reverse transcription-polymerase chain reaction and Western blot analyses were used to assess UGT1A levels in the normal urothelium SVHUC cell line stably expressed with AR and in bladder tissues from AR knockout (ARKO) and castrated male mice. Immunohistochemistry was also performed in radical cystectomy specimens. Dihydrotestosterone (DHT) treatment in SVHUC-AR reduced mRNA expression of all the UGT1A subtypes (19-75% decrease), and hydroxyflutamide antagonized the DHT effects. In contrast, DHT showed only marginal effects on UGT1A expression in SVHUC-Vector. Of note were higher expression levels of UGT1As in SVHUC-Vector than in SVHUC-AR. In ARKO mice, all the Ugt1a subtypes were up-regulated, compared to wild-type littermates. In wild-type male mice, castration increased the expression of Ugt1a8, Ugt1a9, and Ugt1a10. Additionally, wild-type female mice had higher levels of Ugt1a than wild-type males. Immunohistochemical studies showed strong (3+) UGT1A staining in 11/24 (46%) cancer tissues, which was significantly lower than in corresponding benign tissues [17/18 (94%) cases (P = 0.0009)]. These results suggest that androgen-mediated AR signals promote bladder carcinogenesis by down-regulating the expression of UGTs in the bladder. Copyright © 2011 Wiley Periodicals, Inc.

  17. Determination of sites of U50,488H-promoted phosphorylation of the mouse κ opioid receptor (KOPR): disconnect between KOPR phosphorylation and internalization.

    Science.gov (United States)

    Chen, Chongguang; Chiu, Yi-Ting; Wu, Wenman; Huang, Peng; Mann, Anika; Schulz, Stefan; Liu-Chen, Lee-Yuan

    2016-02-15

    Phosphorylation sites of KOPR (κ opioid receptor) following treatment with the selective agonist U50,488H {(-)(trans)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidiny)cyclo-hexyl]benzeneacetamide} were identified after affinity purification, SDS/PAGE, in-gel digestion with Glu-C and HPLC-MS/MS. Single- and double-phosphorylated peptides were identified containing phosphorylated Ser(356), Thr(357), Thr(363) and Ser(369) in the C-terminal domain. Antibodies were generated against three phosphopeptides containing pSer(356)/pThr(357), pThr(363) and pSer(369) respectively, and affinity-purified antibodies were found to be highly specific for phospho-KOPR. U50,488H markedly enhanced staining of the KOPR by pThr(363)-, pSer(369)- and pSer(356)/pThr(357)-specific antibodies in immunoblotting, which was blocked by the selective KOPR antagonist norbinaltorphimine. Ser(369) phosphorylation affected Thr(363) phosphorylation and vice versa, and Thr(363) or Ser(369) phosphorylation was important for Ser(356)/Thr(357) phosphorylation, revealing a phosphorylation hierarchy. U50,488H, but not etorphine, promoted robust KOPR internalization, although both were full agonists. U50,488H induced higher degrees of phosphorylation than etorphine at Ser(356)/Thr(357), Thr(363) and Ser(369) as determined by immunoblotting. Using SILAC (stable isotope labelling by amino acids in cell culture) and HPLC-MS/MS, we found that, compared with control (C), U50,488H (U) and etorphine (E) KOPR promoted single phosphorylation primarily at Thr(363) and Ser(369) with U/E ratios of 2.5 and 2 respectively. Both induced double phosphorylation at Thr(363)+Ser(369) and Thr(357)+Ser(369) with U/E ratios of 3.3 and 3.4 respectively. Only U50,488H induced triple phosphorylation at Ser(356)+Thr(357)+Ser(369). An unphosphorylated KOPR-(354-372) fragment containing all of the phosphorylation sites was detected with a C/E/U ratio of 1/0.7/0.4, indicating that ∼60% and ∼30% of the mouse KOPR are phosphorylated

  18. Characterization of phosphorylation sites in the cytoplasmic domain of the 300 kDa mannose-6-phosphate receptor

    DEFF Research Database (Denmark)

    Rosorius, O; Mieskes, G; Issinger, O G

    1993-01-01

    The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation and the phosphorylat......The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation...... and the phosphorylation sites the entire coding sequence of the cytoplasmic tail was expressed in Escherichia coli. The isolated cytoplasmic domain was used as a substrate for four purified serine/threonine kinases [casein kinase II (CK II), protein kinase A (PKA), protein kinase C and Ca2+/calmodulin kinase]. All...... kinases phosphorylate the cytoplasmic tail exclusively on serine residues. Inhibition studies using synthetic peptides, partial sequencing of isolated tryptic phosphopeptides and co-migration with tryptic phosphopeptides from MPR 300 labelled in vivo showed that (i) PKA phosphorylates the cytoplasmic MPR...

  19. Molecular and Biochemical Effects of a Kola Nut Extract on Androgen Receptor-Mediated Pathways

    Directory of Open Access Journals (Sweden)

    Rajasree Solipuram

    2009-01-01

    Full Text Available The low incidence of prostate cancer in Asians has been attributed to chemopreventative properties of certain chemicals found in their diet. This study characterized the androgenic and chemopreventative properties of the Jamaican bush tea “Bizzy,” using androgen receptor positive and negative cell lines. Exposure of prostate cells to Biz-2 resulted in a growth inhibition (GI50 of 15 ppm in LNCaP cells and 3.6 ppm in DU145 cells. Biz-2 elicited a 2-fold increase in the mRNA of the anti-apoptotic gene Bcl2, with a 10-fold increase in that of the proapoptotic gene Bax. We observed a 2.4- to 7.5-fold change in apoptotic cells in both cell lines. Biz-2 at 10 ppm elicited a time- and dose-dependent stimulation of both the protein and mRNA levels of several androgen-regulated genes. Biz-2 caused a 36% decrease in PSA secretion and a significant increase in PSA mRNA. The relative binding affinity (IC50 of Biz-2 for AR was 2- to 5-fold lower than that of the synthetic androgen R1881. Biz-2 was found to be a specific ligand for the AR in that the natural ligand, DHT, and the anti-androgen, flutamide, displaced Biz-2 bound to AR and inhibited Biz-2-induced transcription and PSA secretion. This study provided evidence that Biz-2 extract possesses the ability to modulate prostate cancer cell biology in an AR-dependent manner.

  20. Non-linear association between androgen receptor CAG and GGN repeat lengths and reproductive parameters in fertile European and Inuit men

    DEFF Research Database (Denmark)

    Brokken, L J S; Rylander, L; Jönsson, B A

    2013-01-01

    Recently the dogma that there is an inverse linear association between androgen receptor (AR) CAG and GGN polymorphisms and receptor activity has been challenged. We analysed the pattern of association between 21 male reproductive phenotypes and AR CAG/GGN repeat lengths in 557 proven-fertile men...

  1. Somatic mosaicism of androgen receptor CAG repeats in colorectal carcinoma epithelial cells from men.

    Science.gov (United States)

    Di Fabio, Francesco; Alvarado, Carlos; Gologan, Adrian; Youssef, Emad; Voda, Linda; Mitmaker, Elliot; Beitel, Lenore K; Gordon, Philip H; Trifiro, Mark

    2009-06-01

    The X-linked human androgen receptor gene (AR) contains an exonic polymorphic trinucleotide CAG. The length of this encoded CAG tract inversely affects AR transcriptional activity. Colorectal carcinoma is known to express the androgen receptor, but data on somatic CAG repeat lengths variations in malignant and normal epithelial cells are still sporadic. Using laser capture microdissection (LCM), epithelial cells from colorectal carcinoma and normal-appearing mucosa were collected from the fresh tissue of eight consecutive male patients undergoing surgery (mean age, 70 y; range, 54-82). DNA isolated from each LCM sample underwent subsequent PCR and DNA sequencing to precisely determine AR CAG repeat lengths and the presence of microsatellite instability (MSI). Different AR CAG repeat lengths were observed in colorectal carcinoma (ranging from 0 to 36 CAG repeats), mainly in the form of multiple shorter repeat lengths. This genetic heterogeneity (somatic mosaicism) was also found in normal-appearing colorectal mucosa. Half of the carcinoma cases examined tended to have a higher number of AR CAG repeat lengths with a wider range of repeat size variation compared to normal mucosa. MSI carcinomas tended to have longer median AR CAG repeat lengths (n = 17) compared to microsatellite stable carcinomas (n = 14), although the difference was not significant (P = 0.31, Mann-Whitney test). Multiple unique somatic mutations of the AR CAG repeats occur in colorectal mucosa and in carcinoma, predominantly resulting in shorter alleles. Colorectal epithelial cells carrying AR alleles with shorter CAG repeat lengths may be more androgen-sensitive and therefore have a growth advantage.

  2. Androgen receptor expression in Circulating Tumor Cells from castration-resistant prostate cancer patients with novel endocrine agents

    NARCIS (Netherlands)

    Crespo, M.; van Dalum, Guus; Ferraldeschi, R.; Zafeiriou, Z.; Sideris, S.; Lorente, D.; Bianchini, D.; Rodrigues, D.N.; Rijsnaes, R.; Miranda, S.; Figueiredo, I.; Flohr, P.; Nowakowska, K.; de Bono, J.S.; Terstappen, Leonardus Wendelinus Mathias Marie; Attard, G.

    2015-01-01

    Background: Abiraterone and enzalutamide are novel endocrine treatments that abrogate androgen receptor (AR) signalling in castration-resistant prostate cancer (CRPC). Here, we developed a circulating tumour cells (CTCs)-based assay to evaluate AR expression in real-time in CRPC and investigated

  3. The role of glucocorticoid receptor phosphorylation in Mcl-1 and NOXA gene expression

    Directory of Open Access Journals (Sweden)

    Demonacos Constantinos

    2010-02-01

    Full Text Available Abstract Background The cyclin-dependent kinase (CDK and mitogen-activated protein kinase (MAPK mediated phosphorylation of glucocorticoid receptor (GR exerts opposite effects on GR transcriptional activity and affects other posttranslational modifications within this protein. The major phosphorylation site of human GR targeted by MAPK family is the serine 226 and multiple kinase complexes phosphorylate receptor at the serine 211 residue. We hypothesize that GR posttranslational modifications are involved in the determination of the cellular fate in human lymphoblastic leukemia cells. We investigated whether UV signalling through alternative GR phosphorylation determined the cell type specificity of glucocorticoids (GCs mediated apoptosis. Results We have identified putative Glucocorticoid Response Elements (GREs within the promoter regulatory regions of the Bcl-2 family members NOXA and Mcl-1 indicating that they are direct GR transcriptional targets. These genes were differentially regulated in CEM-C7-14, CEM-C1-15 and A549 cells by glucocorticoids and JNK pathway. In addition, our results revealed that the S211 phosphorylation was dominant in CEM-C7-14, whereas the opposite was the case in CEM-C1-15 where prevalence of S226 GR phosphorylation was observed. Furthermore, multiple GR isoforms with cell line specific patterns were identified in CEM-C7-14 cells compared to CEM-C1-15 and A549 cell lines with the same antibodies. Conclusions GR phosphorylation status kinetics, and site specificity as well as isoform variability differ in CEM-C7-14, CEM-C1-15, and A549 cells. The positive or negative response to GCs induced apoptosis in these cell lines is a consequence of the variable equilibrium of NOXA and Mcl-1 gene expression potentially mediated by alternatively phosphorylated GR, as well as the balance of MAPK/CDK pathways controlling GR phosphorylation pattern. Our results provide molecular base and valuable knowledge for improving the GC

  4. 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

  5. Multivalent Peptidomimetic Conjugates as Inhibitors of Androgen Receptor Function in Therapy-Resistant Prostate Cancer

    Science.gov (United States)

    2017-10-01

    treat patients with prostate cancer, over time the tumors become resistant to the drugs, leaving few treatment options. The goal of this proposal is to...interactions with the AR. 15. SUBJECT TERMS androgen receptor, prostate cancer, peptidomimetic conjugates, 16. SECURITY CLASSIFICATION OF: 17...used successfully to treat patients with prostate cancer, over time the tumors become resistant to the drugs, leaving few treatment options. The goal

  6. Stromal androgen receptor roles in the development of normal prostate, benign prostate hyperplasia, and prostate cancer.

    Science.gov (United States)

    Wen, Simeng; Chang, Hong-Chiang; Tian, Jing; Shang, Zhiqun; Niu, Yuanjie; Chang, Chawnshang

    2015-02-01

    The prostate is an androgen-sensitive organ that needs proper androgen/androgen receptor (AR) signals for normal development. The progression of prostate diseases, including benign prostate hyperplasia (BPH) and prostate cancer (PCa), also needs proper androgen/AR signals. Tissue recombination studies report that stromal, but not epithelial, AR plays more critical roles via the mesenchymal-epithelial interactions to influence the early process of prostate development. However, in BPH and PCa, much more attention has been focused on epithelial AR roles. However, accumulating evidence indicates that stromal AR is also irreplaceable and plays critical roles in prostate disease progression. Herein, we summarize the roles of stromal AR in the development of normal prostate, BPH, and PCa, with evidence from the recent results of in vitro cell line studies, tissue recombination experiments, and AR knockout animal models. Current evidence suggests that stromal AR may play positive roles to promote BPH and PCa progression, and targeting stromal AR selectively with AR degradation enhancer, ASC-J9, may allow development of better therapies with fewer adverse effects to battle BPH and PCa. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  7. The androgen receptor malignancy shift in prostate cancer.

    Science.gov (United States)

    Copeland, Ben T; Pal, Sumanta K; Bolton, Eric C; Jones, Jeremy O

    2018-05-01

    Androgens and the androgen receptor (AR) are necessary for the development, function, and homeostatic growth regulation of the prostate gland. However, once prostate cells are transformed, the AR is necessary for the proliferation and survival of the malignant cells. This change in AR function appears to occur in nearly every prostate cancer. We have termed this the AR malignancy shift. In this review, we summarize the current knowledge of the AR malignancy shift, including the DNA-binding patterns that define the shift, the transcriptome changes associated with the shift, the putative drivers of the shift, and its clinical implications. In benign prostate epithelial cells, the AR primarily binds consensus AR binding sites. In carcinoma cells, the AR cistrome is dramatically altered, as the AR associates with FOXA1 and HOXB13 motifs, among others. This shift leads to the transcription of genes associated with a malignant phenotype. In model systems, some mutations commonly found in localized prostate cancer can alter the AR cistrome, consistent with the AR malignancy shift. Current evidence suggests that the AR malignancy shift is necessary but not sufficient for transformation of prostate epithelial cells. Reinterpretation of prostate cancer genomic classification systems in light of the AR malignancy shift may improve our ability to predict clinical outcomes and treat patients appropriately. Identifying and targeting the molecular factors that contribute to the AR malignancy shift is not trivial but by doing so, we may be able to develop new strategies for the treatment or prevention of prostate cancer. © 2018 Wiley Periodicals, Inc.

  8. PCA3 Silencing Sensitizes Prostate Cancer Cells to Enzalutamide-mediated Androgen Receptor Blockade.

    Science.gov (United States)

    Özgür, Emre; Celik, Ayca Iribas; Darendeliler, Emin; Gezer, Ugur

    2017-07-01

    Prostate cancer (PCa) is an androgen-dependent disease. Novel anti-androgens (i.e. enzalutamide) have recently been developed for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC). Evidence is accumulating that prostate cancer antigen 3 (PCA3) is involved in androgen receptor (AR) signaling. Here, in combination with enzalutamide-mediated AR blockade, we investigated the effect of PCA3 targeting on the viability of PCa cells. In hormone-sensitive LNCaP cells, AR-overexpressing LNCaP-AR + cells and VCaP cells (representing CRPC), PCA3 was silenced using siRNA oligonucleotides. Gene expression and cell viability was assessed in PCA3-silenced and/or AR-blocked cells. PCA3 targeting reduced the expression of AR-related genes (i.e. prostate-specific antigen (PSA) and prostate-specific transcript 1 (non-protein coding) (PCGEM1)) and potentiated the effect of enzalutamide. Proliferation of PCa cells was suppressed upon PCA3 silencing with a greater effect in LNCaP-AR + cells. Furthermore, PCA3 silencing sensitized PCa cells to enzalutamide-induced loss of cell growth. PCA3, as a therapeutic target in PCa, might be used to potentiate AR antagonists. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  9. Polymorphic variation in the androgen receptor gene: association with risk of testicular germ cell cancer and metastatic disease

    DEFF Research Database (Denmark)

    Västermark, Åke; Giwercman, Yvonne Lundberg; Hagströmer, Oskar

    2011-01-01

    Increasing incidence of testicular germ cell cancer (TGCC) is most probably related to environment and lifestyle. However, an underlying genetic predisposition may play a role and since sex steroids are assumed to be important for the rise and progression of TGCC, a study of androgen receptor (AR...... of endocrine disruptors. From a biological point of view, our findings strengthen the hypothesis of the importance of androgen action in the aetiology and pathogenesis of testicular malignancy. Future studies should focus on the impact of sex hormones on foetal germ cell development and the interaction between...

  10. Androgen receptor activation: a prospective therapeutic target for bladder cancer?

    Science.gov (United States)

    Mizushima, Taichi; Tirador, Kathleen A; Miyamoto, Hiroshi

    2017-03-01

    Patients with non-muscle-invasive or muscle-invasive bladder cancer undergoing surgery and currently available conventional therapy remain having a high risk of tumor recurrence or progression, respectively. Novel targeted molecular therapy is therefore expected to improve patient outcomes. Meanwhile, substantially higher incidence of bladder cancer in men has prompted research on androgen-mediated androgen receptor (AR) signaling in this malignancy. Indeed, preclinical evidence has suggested that AR signaling plays an important role in urothelial carcinogenesis and tumor outgrowth as well as resistance to some of the currently available conventional non-surgical therapies. Areas covered: We summarize and discuss available data suggesting the involvement of AR and its potential downstream targets in the development and progression of bladder cancer. Associations between AR signaling and sensitivity to cisplatin/doxorubicin or bacillus Calmette-Guérin treatment are also reviewed. Expert opinion: AR activation is likely to correlate with the promotion of urothelial carcinogenesis and cancer outgrowth as well as resistance to conventional therapies. Molecular therapy targeting the AR may thus provide effective chemopreventive and therapeutic approaches for urothelial cancer. Accordingly, bladder cancer can now be considered as an endocrine-related neoplasm. Clinical application of various anti-AR therapies available for AR-dependent prostate cancer to bladder cancer patients is anticipated.

  11. Activation of estrogen receptor beta (ERβ) regulates the expression of N-cadherin, E-cadherin and β-catenin in androgen-independent prostate cancer cells.

    Science.gov (United States)

    Silva, Rafael de Souza; Lombardi, Ana Paola G; de Souza, Deborah Simão; Vicente, Carolina M; Porto, Catarina S

    2018-03-01

    The aim of the present study was to investigate the impact of the activation of estrogen receptors on expression and localization of N-cadherin, E-cadherin and non-phosphorylated β-catenin in androgen-independent prostate cancer cells (PC-3 and DU-145) and in human post pubertal prostate epithelial cells (PNT1A). Expression of N-cadherin was detected in PNT1A and PC-3 cells, but not in DU-145 cells. E-cadherin was detected only in DU-145 cells and β-catenin was detected in all cells studied. N-cadherin and β-catenin were located preferentially in the cellular membrane of PNT1A cells and in the cytoplasm of PC-3 cells. E-cadherin and β-catenin were located preferentially in the cellular membrane of DU-145 cells. 17β-estradiol (E2) or the ERα-selective agonist PPT did not affect the content and localization of N-cadherin in PC-3 and PNT1A cells or E-cadherin in DU-145 cells. In PC-3 cells, ERβ-selective agonist DPN decreased the expression of N-cadherin. DPN-induced downregulation of N-cadherin was blocked by pretreatment with the ERβ-selective antagonist (PHTPP), indicating that ERβ1 is the upstream receptor regulating the expression of N-cadherin. In DU-145 cells, the activation of ERβ1 by DPN increased the expression of E-cadherin. Taken together, these results suggest that activation of ERβ1 is required to maintain an epithelial phenotype in PC-3 and DU-145 cells. The activation of ERβ1 also increased the expression of β-catenin in cytoplasm of PC-3 and in the cellular membrane of DU-145 cells. In conclusion, our results indicate differential expression and localization of N-cadherin, E-cadherin and β-catenin in androgen-independent prostate cancer cells. The reduction of N-cadherin content by activation of ERβ, exclusively observed in androgen-independent prostate cancer cells (PC-3), may be related to the activation of signaling pathways, such as the release of β-catenin into the cytoplasm, translocation of β-catenin to the nucleus and

  12. Androgen receptor signalling in peritubular myoid cells is essential for normal differentiation and function of adult Leydig cells

    DEFF Research Database (Denmark)

    Welsh, M.; Moffat, L.; Belling, Kirstine Christensen

    2012-01-01

    Testosterone synthesis depends on normal Leydig cell (LC) development, but the mechanisms controlling this development remain unclear. We recently demonstrated that androgen receptor (AR) ablation from a proportion of testicular peritubular myoid cells (PTM-ARKO) did not affect LC number, but res......Testosterone synthesis depends on normal Leydig cell (LC) development, but the mechanisms controlling this development remain unclear. We recently demonstrated that androgen receptor (AR) ablation from a proportion of testicular peritubular myoid cells (PTM-ARKO) did not affect LC number......’ subpopulation that had arrested development and only weakly expressed INSL3, luteinizing hormone receptor, and several steroidogenic enzymes. Furthermore, unlike ‘normal’ LCs in PTM-ARKOs, the ‘abnormal’ LCs did not involute as expected in response to exogenous testosterone. Differential function of these LC...... sub-populations is likely to mean that the ‘normal’ LCs work harder to compensate for the ‘abnormal’ LCs to maintain normal serum testosterone. These findings reveal new paracrine mechanisms underlying adult LC development, which can be further investigated using PTM-ARKOs....

  13. Screening of synthetic and natural product databases: Identification of novel androgens and antiandrogens.

    Science.gov (United States)

    Bobach, Claudia; Tennstedt, Stephanie; Palberg, Kristin; Denkert, Annika; Brandt, Wolfgang; de Meijere, Armin; Seliger, Barbara; Wessjohann, Ludger A

    2015-01-27

    The androgen receptor is an important pharmaceutical target for a variety of diseases. This paper presents an in silico/in vitro screening procedure to identify new androgen receptor ligands. The two-step virtual screening procedure uses a three-dimensional pharmacophore model and a docking/scoring routine. About 39,000 filtered compounds were docked with PLANTS and scored by Chemplp. Subsequent to virtual screening, 94 compounds, including 28 steroidal and 66 nonsteroidal compounds, were tested by an androgen receptor fluorescence polarization ligand displacement assay. As a result, 30 compounds were identified that show a relative binding affinity of more than 50% in comparison to 100 nM dihydrotestosterone and were classified as androgen receptor binders. For 11 androgen receptor binders of interest IC50 and Ki values were determined. The compound with the highest affinity exhibits a Ki value of 10.8 nM. Subsequent testing of the 11 compounds in a PC-3 and LNCaP multi readout proliferation assay provides insights into the potential mode of action. Further steroid receptor ligand displacement assays and docking studies on estrogen receptors α and β, glucocorticoid receptor, and progesterone receptor gave information about the specificity of the 11 most active compounds. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  14. Restoration of spermatogenesis and male fertility using an androgen receptor transgene.

    Directory of Open Access Journals (Sweden)

    William H Walker

    Full Text Available Androgens signal through the androgen receptor (AR to regulate male secondary sexual characteristics, reproductive tract development, prostate function, sperm production, bone and muscle mass as well as body hair growth among other functions. We developed a transgenic mouse model in which endogenous AR expression was replaced by a functionally modified AR transgene. A bacterial artificial chromosome (BAC was constructed containing all AR exons and introns plus 40 kb each of 5' and 3' regulatory sequence. Insertion of an internal ribosome entry site and the EGFP gene 3' to AR allowed co-expression of AR and EGFP. Pronuclear injection of the BAC resulted in six founder mice that displayed EGFP production in appropriate AR expressing tissues. The six founder mice were mated into a Sertoli cell specific AR knockout (SCARKO background in which spermatogenesis is blocked at the meiosis stage of germ cell development. The AR-EGFP transgene was expressed in a cyclical manner similar to that of endogenous AR in Sertoli cells and fertility was restored as offspring were produced in the absence of Sertoli cell AR. Thus, the AR-EGFP transgene under the control of AR regulatory elements is capable of rescuing AR function in a cell selective, AR-null background. These initial studies provide proof of principle that a strategy employing the AR-EGFP transgene can be used to understand AR functions. Transgenic mice expressing selective modifications of the AR-EGFP transgene may provide crucial information needed to elicit the molecular mechanisms by which AR acts in the testis and other androgen responsive tissues.

  15. Heterologous activation of protein kinase C stimulates phosphorylation of delta-opioid receptor at serine 344, resulting in beta-arrestin- and clathrin-mediated receptor internalization

    DEFF Research Database (Denmark)

    Xiang, B; Yu, G H; Guo, J

    2001-01-01

    The purpose of the current study is to investigate the effect of opioid-independent, heterologous activation of protein kinase C (PKC) on the responsiveness of opioid receptor and the underlying molecular mechanisms. Our result showed that removing the C terminus of delta opioid receptor (DOR......) containing six Ser/Thr residues abolished both DPDPE- and phorbol 12-myristate 13-acetate (PMA)-induced DOR phosphorylation. The phosphorylation levels of DOR mutants T352A, T353A, and T358A/T361A/S363S were comparable to that of the wild-type DOR, whereas S344G substitution blocked PMA-induced receptor......, and ionomycin resulted in DOR internalization that required phosphorylation of Ser-344. Expression of dominant negative beta-arrestin and hypertonic sucrose treatment blocked PMA-induced DOR internalization, suggesting that PKC mediates DOR internalization via a beta-arrestin- and clathrin-dependent mechanism...

  16. Variation in melatonin receptors (Mel(1a) and Mel(1b)) and androgen receptor (AR) expression in the spleen of a seasonally breeding bird, Perdicula asiatica.

    Science.gov (United States)

    Yadav, S K; Haldar, C; Singh, S S

    2011-12-01

    Daily variation in the peripheral level of melatonin plays a major role in integrating reproduction and environmental information for seasonally breeding birds. However, the variation in immunity and reproduction has never been assessed in any avian species on a 24 h time scale. Therefore, to understand the relationship between immune function and reproductive phases in a seasonally breeding bird, Perdicula asiatica, the Indian jungle bush quail, we studied the daily variation of melatonin and testosterone levels along with expression of their receptors Mel(1a), Mel(1b), and androgen receptor in the spleen during the reproductively active phase. Immunocytochemistry for the melatonin receptors Mel(1a) and Mel(1b) presented a differential distribution pattern. Western blot of splenic protein suggested a daily rhythm of melatonin receptors, while acrophases for the two melatonin receptors Mel(1a) and Mel(1b) differed by 4 h, suggesting that the expression of the receptors may peak at different times, causing more of either Mel(1a) or Mel(1b) to be available at a particular time to mediate function. The circulatory melatonin level correlated with percentage stimulation ratio of splenocytes and plasma interleukin-2 level, but did not correlate with testosterone or androgen receptor, suggesting that melatonin could be a major hormone imparting a time-of-day effect on the modulation of immune function in a seasonally breeding bird during the reproductively active phase. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  17. Loss and recovery of androgen receptor protein expression in the adult rat testis following androgen withdrawal by ethane dimethanesulfonate.

    Directory of Open Access Journals (Sweden)

    Boycho Nikolov

    2006-06-01

    Full Text Available Androgens are especially important for the maintenance of spermatogenesis in adulthood and the experimental withdrawal of testosterone (T production by ethane dimenthanesulfonate (EDS is a valuable tool for studying androgen-dependent events of spermatogenesis. The aim of the present study was to investigate the specific changes in immunoexpression of androgen receptor (AR in the testis in relation to degeneration and regeneration of Leydig cell (LC population and seminiferous epithelium. Immunohistochemistry for AR and 3beta-hydroxysteroid dehydrogenase (3beta-HSD as well as TUNEL assay for apoptosis were performed on testicular sections of control and EDS-treated rats. Serum LH and T levels were measured by RIA. Our results revealed a total loss of AR immunoexpression from the nuclei of Sertoli (SCs, LCs and peritubular cells during the first week after EDS administration and that coincided with severe drop in T levels. Two weeks after EDS administration, the AR expression was recovered in these cells but normal stage-specificity in SCs was replaced by uniform intensity of AR immunostaining at all the stages of the spermatogenic cycle. The stage-specific pattern of androgen expression in SCs with a maximum at stages VII-VIII appeared 5 weeks after treatment. LC immunoreactivity for 3beta-HSD at different time points after EDS administration correlated with values of T concentration. The maximal germ cell apoptosis on day 7 was followed by total loss of elongated spermatids 2 weeks after EDS treatment. Regeneration of seminiferous epithelium 3 weeks after EDS administration and onwards occurred in tandem with the development of new LC population indicated by the appearance of 3beta-HSD-positive cells and gradual increase in T production. The specific changes in AR after EDS including their loss and recovery in Sertoli cells paralleled with degenerative and regenerative events in Leydig and germ cell populations, confirming close functional

  18. Tzfp represses the androgen receptor in mouse testis.

    Science.gov (United States)

    Furu, Kari; Klungland, Arne

    2013-01-01

    The testis zinc finger protein (Tzfp), also known as Repressor of GATA, belongs to the BTB/POZ zinc finger family of transcription factors and is thought to play a role in spermatogenesis due to its remarkably high expression in testis. Despite many attempts to find the in vivo role of the protein, the molecular function is still largely unknown. Here, we address this issue using a novel mouse model with a disrupted Tzfp gene. Homozygous Tzfp null mice are born at reduced frequency but appear viable and fertile. Sertoli cells in testes lacking Tzfp display an increase in Androgen Receptor (AR) signaling, and several genes in the testis, including Gata1, Aie1 and Fanc, show increased expression. Our results indicate that Tzfp function as a transcriptional regulator and that loss of the protein leads to alterations in AR signaling and reduced number of apoptotic cells in the testicular tubules.

  19. Substitution of aspartic acid-686 by histidine or asparagine in the human androgen receptor leads to a functionally inactive protein with altered hormone-binding characteristics

    NARCIS (Netherlands)

    Ris-Stalpers, C.; Trifiro, M. A.; Kuiper, G. G.; Jenster, G.; Romalo, G.; Sai, T.; van Rooij, H. C.; Kaufman, M.; Rosenfield, R. L.; Liao, S.

    1991-01-01

    We have identified two different single nucleotide alterations in codon 686 (GAC; aspartic acid) in exon 4 of the human androgen receptor gene in three unrelated families with the complete form of androgen insensitivity. One mutation (G----C) results in an aspartic acid----histidine substitution

  20. Partial Androgen Insensitivity Syndrome Presenting with Gynecomastia

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    2015-06-01

    Full Text Available Gynecomastia is a benign enlargement of the male breast caused by the proliferation of glandular breast tissue. Determining the various causes of gynecomastia such as physiological causes, drugs, systemic diseases, and endocrine disorders is important. Androgen insensitivity syndrome (AIS is a rare endocrine disorder presenting with gynecomastia and is a disorder of male sexual differentiation caused by mutations within the androgen receptor gene. All individuals with AIS have the 46 XY karyotype, although AIS phenotypes can be classified as mild, partial or complete and can differ among both males and females including ambiguous genitalia or infertility in males. We experienced a case of partial AIS presenting with gynecomastia and identified the androgen receptor gene mutation.

  1. Androgens as double-edged swords: Induction and suppression of follicular development.

    Science.gov (United States)

    Pan, Jie-Xue; Zhang, Jun-Yu; Ke, Zhang-Hong; Wang, Fang-Fang; Barry, John A; Hardiman, Paul J; Qu, Fan

    2015-01-01

    Androgens, which are mediated via the androgen receptor (AR), play important roles in normal follicular development and female fertility. However, just like a double-edged sword, besides the positive effects of androgen on follicular development, abnormal androgen levels, especially as in hyperandrogenism, seriously suppress normal follicular development. A crucial balance exists between the importance of androgens in follicular development and their negative effects when in excess. As the first meiotic division and epigenetic reprogramming are two critical events in oogenesis, abnormal androgen levels or deficiency in androgen/AR signaling in the ovary may affect these vital events. Oocytes have a tendency to develop genomic instability, thus resulting in an increasing incidence of unpredictable adult diseases. Although many studies have explored the effects of androgens and AR on follicular development, the conclusions are controversial and there has been no thorough review of this topic. This review focuses on the roles of androgens in the physiological process of follicular development, summarizes new insights into the roles of androgens in the arrested development of follicles, and discusses the potential risk of adult diseases originating from abnormal follicular androgen levels or androgen receptor signals, which may determine areas for future studies.

  2. Multivalent Peptidomimetic Conjugates as Inhibitors of Androgen Receptor Function in Therapy-Resistant Prostate Cancer

    Science.gov (United States)

    2016-10-01

    findings in the journal Cancer Research. 15. SUBJECT TERMS androgen receptor, prostate cancer, peptidomimetic conjugates, 16. SECURITY CLASSIFICATION OF...CAN-16-0385. Epub 2016 Aug 3, which is widely read by basic and clinical oncologists. The study was also highlighted in the journal Nature Reviews...This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Received February 11

  3. Performance comparison of two androgen receptor splice variant 7 (AR-V7) detection methods.

    Science.gov (United States)

    Bernemann, Christof; Steinestel, Julie; Humberg, Verena; Bögemann, Martin; Schrader, Andres Jan; Lennerz, Jochen K

    2018-01-23

    To compare the performance of two established androgen receptor splice variant 7 (AR-V7) mRNA detection systems, as paradoxical responses to next-generation androgen-deprivation therapy in AR-V7 mRNA-positive circulating tumour cells (CTC) of patients with castration-resistant prostate cancer (CRPC) could be related to false-positive classification using detection systems with different sensitivities. We compared the performance of two established mRNA-based AR-V7 detection technologies using either SYBR Green or TaqMan chemistries. We assessed in vitro performance using eight genitourinary cancer cell lines and serial dilutions in three AR-V7-positive prostate cancer cell lines, as well as in 32 blood samples from patients with CRPC. Both assays performed identically in the cell lines and serial dilutions showed identical diagnostic thresholds. Performance comparison in 32 clinical patient samples showed perfect concordance between the assays. In particular, both assays determined AR-V7 mRNA-positive CTCs in three patients with unexpected responses to next-generation anti-androgen therapy. Thus, technical differences between the assays can be excluded as the underlying reason for the unexpected responses to next-generation anti-androgen therapy in a subset of AR-V7 patients. Irrespective of the method used, patients with AR-V7 mRNA-positive CRPC should not be systematically precluded from an otherwise safe treatment option. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.

  4. The emerging role of the androgen receptor in bladder cancer.

    Science.gov (United States)

    Lombard, Alan P; Mudryj, Maria

    2015-10-01

    Men are three to four times more likely to get bladder cancer than women. The gender disparity characterizing bladder cancer diagnoses has been investigated. One hypothesis is that androgen receptor (AR) signaling is involved in the etiology and progression of this disease. Although bladder cancer is not typically described as an endocrine-related malignancy, it has become increasingly clear that AR signaling plays a role in bladder tumors. This review summarizes current findings regarding the role of the AR in bladder cancer. We discuss work demonstrating AR expression in bladder cancer and its role in promoting formation and progression of tumors. Additionally, we discuss the therapeutic potential of targeting the AR in this disease. © 2015 Society for Endocrinology.

  5. Effects of Sorafenib on C-Terminally Truncated Androgen Receptor Variants in Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Mark Schrader

    2012-09-01

    Full Text Available Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR. A putative mechanism allowing prostate cancer (PCa cells to grow under low levels of androgens, is the expression of constitutively active, C-terminally truncated AR lacking the AR-ligand binding domain (LBD. Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa.

  6. Androgen receptor requires JunD as a coactivator to switch on an oxidative stress generation pathway in prostate cancer cells.

    Science.gov (United States)

    Mehraein-Ghomi, Farideh; Basu, Hirak S; Church, Dawn R; Hoffmann, F Michael; Wilding, George

    2010-06-01

    Relatively high oxidative stress levels in the prostate are postulated to be a major factor for prostate carcinogenesis and prostate cancer (CaP) progression. We focused on elucidating metabolic pathways of oxidative stress generation in CaP cells. Previously, we showed that the transcription factor JunD is essential for androgen-induced reactive oxygen species (ROS) production in androgen-dependent human CaP cells. We also recently showed that androgen induces the first and regulatory enzyme spermidine/spermine N1-acetyltransferase (SSAT) in a polyamine catabolic pathway that produces copious amounts of metabolic ROS. Here, we present coimmunoprecipitation and Gaussia luciferase reconstitution assay data that show that JunD forms a complex with androgen-activated androgen receptor (AR) in situ. Our chromatin immunoprecipitation assay data show that JunD binds directly to a specific SSAT promoter sequence only in androgen-treated LNCaP cells. Using a vector containing a luciferase reporter gene connected to the SSAT promoter and a JunD-silenced LNCaP cell line, we show that JunD is essential for androgen-induced SSAT gene expression. The elucidation of JunD-AR complex inducing SSAT expression leading to polyamine oxidation establishes the mechanistic basis of androgen-induced ROS production in CaP cells and opens up a new prostate-specific target for CaP chemopreventive/chemotherapeutic drug development. Copyright 2010 AACR.

  7. Renaturation of the androgen receptor after denaturation in SDS

    International Nuclear Information System (INIS)

    Johnson, M.P.; Young, C.Y.F.; Rowley, D.R.; Tindall, D.J.

    1986-01-01

    Renaturation of the steroid binding activity of receptor proteins is a potentially useful tool for their purification and analysis. Cytosol was prepared from rat Dunning prostate tumor in buffer containing molybdate and then denatured by addition of SDS buffer and heating. Aliquots were precipitated in cold acetone and the resulting pellets were washed and solubilized with a small volume of solution containing a chaotropic agent such as 6M guanidine, 8M urea, or 5M sodium iodide. After a 20-minute incubation, samples were diluted 20-fold with buffer containing 4nM [ 3 H]dihydrotestosterone with or without excess unlabeled dihydrotestosterone. Diluted samples were incubated at 0 0 C for varying periods of time prior to assay of bound radioactivity using hydroxylapatite. A time-course of renaturation after exposure to guanidine showed a steady increase of specific binding activity during the first 7 hrs post-dilution that remained stable up to 22 hrs. Experiments with guanidine consistently demonstrated that 25-50% of binding activity was recoverable. Preliminary results using urea or sodium iodide were similar. Efforts to optimize recovery and to characterize the renatured androgen receptor are in progress

  8. Androgen interacts with exercise through the mTOR pathway to induce skeletal muscle hypertrophy.

    Science.gov (United States)

    Zeng, Fanxing; Zhao, Hua; Liao, Jingwen

    2017-12-01

    This study was designed to investigate the effects of exogenous androgen and resistance exercise on skeletal muscle hypertrophy and the role of the mammalian target of rapamycin (mTOR) signalling during the process. A total of 24 male Sprague-Dawley rats were randomly assigned to sham operation and dihydrotestosterone (DHT) implantation groups with subgroups subjected to sedentary conditions or resistance exercise (SHAM+SED, SHAM+EX, DHT+SED, and DHT+EX). The experimental procedure lasted for 10 days. The mRNA expression of androgen receptor (AR) and insulin-like growth factor I (IGF-I), the expression of myosin heavy chain (MHC), as well as the phosphorylation statuses of AR, mTOR, p70 ribosomal S6 kinase (p70 S6K ), and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) were determined in the white gastrocnemius muscle. The cross sectional area and wet mass of the muscle were also measured. The cross sectional area and MHC expression were significantly higher in SHAM+EX, DHT+SED, and DHT+EX than in SHAM+SED. There was no significant difference among groups in muscle mass. The mRNA expression of AR and IGF-I and the phosphorylation of mTOR, p70 S6K , and 4EBP1 were significantly increased in DHT+SED and SHAM+EX and were significantly enhanced in DHT+EX compared with either DHT or exercise alone. These data show that DHT causes hypertrophy in skeletal muscle and that exercise has a synergistic effect on DHT-induced hypertrophy. Exercise enhances androgen-induced rapid anabolic action, which involves activation of the mTOR pathway.

  9. A highly phosphorylated subpopulation of insulin-like growth factor II/mannose 6-phosphate receptors is concentrated in a clathrin-enriched plasma membrane fraction

    International Nuclear Information System (INIS)

    Corvera, S.; Folander, K.; Clairmont, K.B.; Czech, M.P.

    1988-01-01

    Insulin-like growth factor II (IGF-II)/mannose 6-phosphate (Man-6-P) receptors immunoprecipitated from purified plasma membranes of 32 P-labeled rat adipocytes are markedly heterogenous in their phosphorylation state. Approximately 80% of the plasma membrane receptors are solubilized in 1% (vol/vol) Triton X-100 and are phosphorylated on serine residues at a stoichiometry of ∼ 0.1-0.2 mol of phosphate per mol of receptor. In contrast, 15-20% of the receptors are Triton X-100-insoluble and are phosphorylated on serine and threonine residues at ∼ 4 or 5 mol of phosphate per mol of receptor. This Triton X-100-insoluble membrane subfraction contains only 5% of the total plasma membrane protein and yet contains all of the clathrin heavy chain associated with plasma membrane. Based on the relative yields of protein in the detergent-insoluble material, IGF-II/Man-6-P receptors are concentrated ∼ 3-fold in this clathrin-enriched subfraction. Taken together, these results indicate that insulin decreases the phosphorylation state of a highly phosphorylated subpopulation of IGF-II/Man-6-P receptors on the plasma membrane. In addition, insulin action may prevent the concentration of these receptors in a clathrin-enriched membrane subfraction

  10. Mass spectrometry of selective androgen receptor modulators.

    Science.gov (United States)

    Thevis, Mario; Schänzer, Wilhelm

    2008-07-01

    Nonsteroidal selective androgen receptor modulators (SARMs) are an emerging class of drugs for treatment of various diseases including osteoporosis and muscle wasting as well as the correction of age-related functional decline such as muscle strength and power. Several SARMs, which have advanced to preclinical and clinical trials, are composed of diverse chemical structures including arylpropionamide-, bicyclic hydantoin-, quinoline-, and tetrahydroquinoline-derived nuclei. Since January 2008, SARMs have been categorized as anabolic agents and prohibited by the World Anti-Doping Agency (WADA). Suitable detection methods for these low-molecular weight drugs were based on mass spectrometric approaches, which necessitated the elucidation of dissociation pathways in order to characterize and identify the target analytes in doping control samples as well as potential metabolic products and synthetic analogs. Fragmentation patterns of representatives of each category of SARMs after electrospray ionization (ESI) and collision-induced dissociation (CID) as well as electron ionization (EI) are summarized. The complexity and structural heterogeneity of these drugs is a daunting challenge for detection methods. Copyright 2008 John Wiley & Sons, Ltd.

  11. Zipper-interacting protein kinase is involved in regulation of ubiquitination of the androgen receptor, thereby contributing to dynamic transcription complex assembly.

    Science.gov (United States)

    Felten, A; Brinckmann, D; Landsberg, G; Scheidtmann, K H

    2013-10-10

    We have recently identified apoptosis-antagonizing transcription factor (AATF), tumor-susceptibility gene 101 (TSG101) and zipper-interacting protein kinase (ZIPK) as novel coactivators of the androgen receptor (AR). The mechanisms of coactivation remained obscure, however. Here we investigated the interplay and interdependence between these coactivators and the AR using the endogenous prostate specific antigen (PSA) gene as model for AR-target genes. Chromatin immunoprecipitation in combination with siRNA-mediated knockdown revealed that recruitment of AATF and ZIPK to the PSA enhancer was dependent on AR, whereas recruitment of TSG101 was dependent on AATF. Association of AR and its coactivators with the PSA enhancer or promoter occurred in cycles. Dissociation of AR-transcription complexes was due to degradation because inhibition of the proteasome system by MG132 caused accumulation of AR at enhancer/promoter elements. Moreover, inhibition of degradation strongly reduced transcription, indicating that continued and efficient transcription is based on initiation, degradation and reinitiation cycles. Interestingly, knockdown of ZIPK by siRNA had a similar effect as MG132, leading to reduced transcription but enhanced accumulation of AR at androgen-response elements. In addition, knockdown of ZIPK, as well as overexpression of a dominant-negative ZIPK mutant, diminished polyubiquitination of AR. Furthermore, ZIPK cooperated with the E3 ligase Mdm2 in AR-dependent transactivation, assembled into a single complex on chromatin and phosphorylated Mdm2 in vitro. These results suggest that ZIPK has a crucial role in regulation of ubiquitination and degradation of the AR, and hence promoter clearance and efficient transcription.

  12. Neural protein gamma-synuclein interacting with androgen receptor promotes human prostate cancer progression

    International Nuclear Information System (INIS)

    Chen, Junyi; Jiao, Li; Xu, Chuanliang; Yu, Yongwei; Zhang, Zhensheng; Chang, Zheng; Deng, Zhen; Sun, Yinghao

    2012-01-01

    Gamma-synuclein (SNCG) has previously been demonstrated to be significantly correlated with metastatic malignancies; however, in-depth investigation of SNCG in prostate cancer is still lacking. In the present study, we evaluated the role of SNCG in prostate cancer progression and explored the underlying mechanisms. First, alteration of SNCG expression in LNCaP cell line to test the ability of SNCG on cellular properties in vitro and vivo whenever exposing with androgen or not. Subsequently, the Dual-luciferase reporter assays were performed to evaluate whether the role of SNCG in LNCaP is through AR signaling. Last, the association between SNCG and prostate cancer progression was assessed immunohistochemically using a series of human prostate tissues. Silencing SNCG by siRNA in LNCaP cells contributes to the inhibition of cellular proliferation, the induction of cell-cycle arrest at the G1 phase, the suppression of cellular migration and invasion in vitro, as well as the decrease of tumor growth in vivo with the notable exception of castrated mice. Subsequently, mechanistic studies indicated that SNCG is a novel androgen receptor (AR) coactivator. It interacts with AR and promotes prostate cancer cellular growth and proliferation by activating AR transcription in an androgen-dependent manner. Finally, immunohistochemical analysis revealed that SNCG was almost undetectable in benign or androgen-independent tissues prostate lesions. The high expression of SNCG is correlated with peripheral and lymph node invasion. Our data suggest that SNCG may serve as a biomarker for predicting human prostate cancer progression and metastasis. It also may become as a novel target for biomedical therapy in advanced prostate cancer

  13. A Somatically Acquired Enhancer of the Androgen Receptor Is a Noncoding Driver in Advanced Prostate Cancer. | Office of Cancer Genomics

    Science.gov (United States)

    Increased androgen receptor (AR) activity drives therapeutic resistance in advanced prostate cancer. The most common resistance mechanism is amplification of this locus presumably targeting the AR gene. Here, we identify and characterize a somatically acquired AR enhancer located 650 kb centromeric to the AR. Systematic perturbation of this enhancer using genome editing decreased proliferation by suppressing AR levels. Insertion of an additional copy of this region sufficed to increase proliferation under low androgen conditions and to decrease sensitivity to enzalutamide.

  14. Endocytosis of G protein-coupled receptors is regulated by clathrin light chain phosphorylation.

    Science.gov (United States)

    Ferreira, Filipe; Foley, Matthew; Cooke, Alex; Cunningham, Margaret; Smith, Gemma; Woolley, Robert; Henderson, Graeme; Kelly, Eamonn; Mundell, Stuart; Smythe, Elizabeth

    2012-08-07

    Signaling by transmembrane receptors such as G protein-coupled receptors (GPCRs) occurs at the cell surface and throughout the endocytic pathway, and signaling from the cell surface may differ in magnitude and downstream output from intracellular signaling. As a result, the rate at which signaling molecules traverse the endocytic pathway makes a significant contribution to downstream output. Modulation of the core endocytic machinery facilitates differential uptake of individual cargoes. Clathrin-coated pits are a major entry portal where assembled clathrin forms a lattice around invaginating buds that have captured endocytic cargo. Clathrin assembles into triskelia composed of three clathrin heavy chains and associated clathrin light chains (CLCs). Despite the identification of clathrin-coated pits at the cell surface over 30 years ago, the functions of CLCs in endocytosis have been elusive. In this work, we identify a novel role for CLCs in the regulated endocytosis of specific cargoes. Small interfering RNA-mediated knockdown of either CLCa or CLCb inhibits the uptake of GPCRs. Moreover, we demonstrate that phosphorylation of Ser204 in CLCb is required for efficient endocytosis of a subset of GPCRs and identify G protein-coupled receptor kinase 2 (GRK2) as a kinase that can phosphorylate CLCb on Ser204. Overexpression of CLCb(S204A) specifically inhibits the endocytosis of those GPCRs whose endocytosis is GRK2-dependent. Together, these results indicate that CLCb phosphorylation acts as a discriminator for the endocytosis of specific GPCRs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. In vitro phosphorylation of insulin receptor substrate 1 by protein kinase C-zeta: functional analysis and identification of novel phosphorylation sites.

    Science.gov (United States)

    Sommerfeld, Mark R; Metzger, Sabine; Stosik, Magdalene; Tennagels, Norbert; Eckel, Jürgen

    2004-05-18

    Protein kinase C-zeta (PKC-zeta) participates both in downstream insulin signaling and in the negative feedback control of insulin action. Here we used an in vitro approach to identify PKC-zeta phosphorylation sites within insulin receptor substrate 1 (IRS-1) and to characterize the functional implications. A recombinant IRS-1 fragment (rIRS-1(449)(-)(664)) containing major tyrosine motifs for interaction with phosphatidylinositol (PI) 3-kinase strongly associated to the p85alpha subunit of PI 3-kinase after Tyr phosphorylation by the insulin receptor. Phosphorylation of rIRS-1(449)(-)(664) by PKC-zeta induced a prominent inhibition of this process with a mixture of classical PKC isoforms being less effective. Both PKC-zeta and the classical isoforms phosphorylated rIRS-1(449)(-)(664) on Ser(612). However, modification of this residue did not reduce the affinity of p85alpha binding to pTyr-containing peptides (amino acids 605-615 of rat IRS-1), as determined by surface plasmon resonance. rIRS-1(449)(-)(664) was then phosphorylated by PKC-zeta using [(32)P]ATP and subjected to tryptic phosphopeptide mapping based on two-dimensional HPLC coupled to mass spectrometry. Ser(498) and Ser(570) were identified as novel phosphoserine sites targeted by PKC-zeta. Both sites were additionally confirmed by phosphopeptide mapping of the corresponding Ser --> Ala mutants of rIRS-1(449)(-)(664). Ser(570) was specifically targeted by PKC-zeta, as shown by immunoblotting with a phosphospecific antiserum against Ser(570) of IRS-1. Binding of p85alpha to the S570A mutant was less susceptible to inhibition by PKC-zeta, when compared to the S612A mutant. In conclusion, our in vitro data demonstrate a strong inhibitory action of PKC-zeta at the level of IRS-1/PI 3-kinase interaction involving multiple serine phosphorylation sites. Whereas Ser(612) appears not to participate in the negative control of insulin signaling, Ser(570) may at least partly contribute to this process.

  16. Tzfp represses the androgen receptor in mouse testis.

    Directory of Open Access Journals (Sweden)

    Kari Furu

    Full Text Available The testis zinc finger protein (Tzfp, also known as Repressor of GATA, belongs to the BTB/POZ zinc finger family of transcription factors and is thought to play a role in spermatogenesis due to its remarkably high expression in testis. Despite many attempts to find the in vivo role of the protein, the molecular function is still largely unknown. Here, we address this issue using a novel mouse model with a disrupted Tzfp gene. Homozygous Tzfp null mice are born at reduced frequency but appear viable and fertile. Sertoli cells in testes lacking Tzfp display an increase in Androgen Receptor (AR signaling, and several genes in the testis, including Gata1, Aie1 and Fanc, show increased expression. Our results indicate that Tzfp function as a transcriptional regulator and that loss of the protein leads to alterations in AR signaling and reduced number of apoptotic cells in the testicular tubules.

  17. Unraveling the Complexities of Androgen Receptor Signaling in Prostate Cancer Cells

    OpenAIRE

    Heemers, Hannelore V.; Tindall, Donald J.

    2009-01-01

    Androgen signaling is critical for proliferation of prostate cancer cells but cannot be fully inhibited by current androgen deprivation therapies. A study by Xu et al. in this issue of Cancer Cell provides insights into the complexities of androgen signaling in prostate cancer and suggests avenues to target a subset of androgen-sensitive genes.

  18. Understanding the Differential Selectivity of Arrestins toward the Phosphorylation State of the Receptor

    NARCIS (Netherlands)

    Sensoy, Ozge; de Sousa Moreira, Irina; Morra, Giulia

    2016-01-01

    Proteins in the arrestin family exhibit a conserved structural fold that nevertheless allows for significant differences in their selectivity for G-protein coupled receptors (GPCRs) and their phosphorylation states. To reveal the mechanism of activation that prepares arrestin for selective

  19. Expression profiles and functional associations of endogenous androgen receptor and caveolin-1 in prostate cancer cell lines.

    Science.gov (United States)

    Bennett, Nigel C; Hooper, John D; Johnson, David W; Gobe, Glenda C

    2014-05-01

    In prostate cancer (PCa) patients, the protein target for androgen deprivation and blockade therapies is androgen receptor (AR). AR interacts with many proteins that function to either co-activate or co-repress its activity. Caveolin-1 (Cav-1) is not found in normal prostatic epithelium, but is found in PCa, and may be an AR co-regulator protein. We investigated cell line-specific signatures and associations of endogenous AR and Cav-1 in six PCa cell lines of known androgen sensitivity: LNCaP (androgen sensitive); 22Rv1 (androgen responsive); PC3, DU145, and ALVA41 (androgen non-reliant); and RWPE1 (non-malignant). Protein and mRNA expression profiles were compared and electron microscopy used to identify cells with caveolar structures. For cell lines expressing both AR and Cav-1, knockdown techniques using small interfering RNA against AR or Cav-1 were used to test whether diminished expression of one affected the other. Co-sedimentation of AR and Cav-1 was used to test their association. A reporter assay for AR genomic activity was utilized following Cav-1 knockdown. AR-expressing LNCaP and 22Rv1 cells had low endogenous Cav-1 mRNA and protein. Cell lines that expressed little or no AR (DU145, PC3, ALVA41, and RWPE1) expressed high endogenous levels of Cav-1. AR knockdown in LNCaP cells had little effect on Cav-1, but Cav-1 knockdown inhibited AR expression and genomic activity. These data show endogenous AR and Cav-1 mRNA and protein expression is inversely related in PCa cells, with Cav-1 acting on the androgen/AR signaling axis possibly as an AR co-activator, demonstrated by diminished AR genomic activity following Cav-1 knockdown. © 2013 Wiley Periodicals, Inc.

  20. Baicalein suppresses the androgen receptor (AR)-mediated prostate cancer progression via inhibiting the AR N-C dimerization and AR-coactivators interaction.

    Science.gov (United States)

    Xu, Defeng; Chen, Qiulu; Liu, Yalin; Wen, Xingqiao

    2017-12-01

    Androgen receptor (AR) plays a critical role in prostate cancer (PCa) development and progression. Androgen deprivation therapy with antiandrogens to reduce androgen biosynthesis or prevent androgens from binding to AR are widely used to suppress AR-mediated PCa growth. However, most of ADT may eventually fail with development of the castration resistance after 12-24 months. Here we found that a natural product baicalein can effectively suppress the PCa progression via targeting the androgen-induced AR transactivation with little effect to AR protein expression. PCa cells including LNCaP, CWR22Rv1, C4-2, PC-3, and DU145, were treated with baicalein and luciferase assay was used to evaluate their effect on the AR transactivation. Cell growth and IC 50 were determined by MTT assay after 48 hrs treatment. RT-PCR was used to evaluate the mRNA levels of AR target genes including PSA, TMPRSS2, and TMEPA1. Western blot was used to determine AR and PSA protein expression. The natural product of baicalein can selectively inhibit AR transactivation with little effect on the other nuclear receptors, including ERα, and GR. At a low concentration, 2.5 μM of baicalein effectively suppresses the growth of AR-positive PCa cells, and has little effect on AR-negative PCa cells. Mechanism dissection suggest that baicalein can suppress AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive LNCaP cells and castration resistant CWR22Rv1 cells, that may involve the inhibiting the AR N/C dimerization and AR-coactivators interaction. Baicalein may be developed as an effective anti-AR therapy via its ability to inhibit AR transactivation and AR-mediated PCa cell growth.

  1. The Safety, Pharmacokinetics, and Effects of LGD-4033, a Novel Nonsteroidal Oral, Selective Androgen Receptor Modulator, in Healthy Young Men

    Science.gov (United States)

    Basaria, Shehzad; Collins, Lauren; Dillon, E. Lichar; Orwoll, Katie; Storer, Thomas W.; Miciek, Renee; Ulloor, Jagadish; Zhang, Anqi; Eder, Richard; Zientek, Heather; Gordon, Gilad; Kazmi, Syed; Sheffield-Moore, Melinda

    2013-01-01

    Background. Concerns about potential adverse effects of testosterone on prostate have motivated the development of selective androgen receptor modulators that display tissue-selective activation of androgenic signaling. LGD-4033, a novel nonsteroidal, oral selective androgen receptor modulator, binds androgen receptor with high affinity and selectivity. Objectives. To evaluate the safety, tolerability, pharmacokinetics, and effects of ascending doses of LGD-4033 administered daily for 21 days on lean body mass, muscle strength, stair-climbing power, and sex hormones. Methods. In this placebo-controlled study, 76 healthy men (21–50 years) were randomized to placebo or 0.1, 0.3, or 1.0 mg LGD-4033 daily for 21 days. Blood counts, chemistries, lipids, prostate-specific antigen, electrocardiogram, hormones, lean and fat mass, and muscle strength were measured during and for 5 weeks after intervention. Results. LGD-4033 was well tolerated. There were no drug-related serious adverse events. Frequency of adverse events was similar between active and placebo groups. Hemoglobin, prostate-specific antigen, aspartate aminotransferase, alanine aminotransferase, or QT intervals did not change significantly at any dose. LGD-4033 had a long elimination half-life and dose-proportional accumulation upon multiple dosing. LGD-4033 administration was associated with dose-dependent suppression of total testosterone, sex hormone–binding globulin, high density lipoprotein cholesterol, and triglyceride levels. follicle-stimulating hormone and free testosterone showed significant suppression at 1.0-mg dose only. Lean body mass increased dose dependently, but fat mass did not change significantly. Hormone levels and lipids returned to baseline after treatment discontinuation. Conclusions. LGD-4033 was safe, had favorable pharmacokinetic profile, and increased lean body mass even during this short period without change in prostate-specific antigen. Longer randomized trials should

  2. ENVIRONMENTAL ANDROGENS AND ANTIANDROGENS: AN EXPANDING CHEMICAL UNIVERSE

    Science.gov (United States)

    Within the last ten years, awareness has grown about environmental chemicals that display antiandrogenic or androgenic activity. While studies in the early 1990s focused on pesticides that acted as androgen receptor (AR) antagonists, it soon became evident that this was not the ...

  3. Development of a New Class of Drugs To Inhibit All Forms of Androgen Receptor in Castration Resistant Prostate Cancers

    Science.gov (United States)

    2016-10-01

    receptor, castration-resistant prostate cancer, DNA binding domain, androgen response element, AR inhibitor, chromatin, x-ray crystallography , pre-clinical...14228 (months 1-30) 3.2. Synthesis of derivatives of our lead compounds (months 6-30). 3.3.Experimental evaluation of the developed synthetic

  4. Choline Kinase Alpha as an Androgen Receptor Chaperone and Prostate Cancer Therapeutic Target

    Science.gov (United States)

    Asim, Mohammad; Massie, Charles E.; Orafidiya, Folake; Pértega-Gomes, Nelma; Warren, Anne Y.; Esmaeili, Mohsen; Selth, Luke A.; Zecchini, Heather I.; Luko, Katarina; Qureshi, Arham; Baridi, Ajoeb; Menon, Suraj; Madhu, Basetti; Escriu, Carlos; Lyons, Scott; Vowler, Sarah L.; Zecchini, Vincent R.; Shaw, Greg; Hessenkemper, Wiebke; Russell, Roslin; Mohammed, Hisham; Stefanos, Niki; Lynch, Andy G.; Grigorenko, Elena; D’Santos, Clive; Taylor, Chris; Lamb, Alastair; Sriranjan, Rouchelle; Yang, Jiali; Stark, Rory; Dehm, Scott M.; Rennie, Paul S.; Carroll, Jason S.; Griffiths, John R.; Tavaré, Simon; Mills, Ian G.; McEwan, Iain J.; Baniahmad, Aria; Tilley, Wayne D.; Neal, David E.

    2016-01-01

    Background: The androgen receptor (AR) is a major drug target in prostate cancer (PCa). We profiled the AR-regulated kinome to identify clinically relevant and druggable effectors of AR signaling. Methods: Using genome-wide approaches, we interrogated all AR regulated kinases. Among these, choline kinase alpha (CHKA) expression was evaluated in benign (n = 195), prostatic intraepithelial neoplasia (PIN) (n = 153) and prostate cancer (PCa) lesions (n = 359). We interrogated how CHKA regulates AR signaling using biochemical assays and investigated androgen regulation of CHKA expression in men with PCa, both untreated (n = 20) and treated with an androgen biosynthesis inhibitor degarelix (n = 27). We studied the effect of CHKA inhibition on the PCa transcriptome using RNA sequencing and tested the effect of CHKA inhibition on cell growth, clonogenic survival and invasion. Tumor xenografts (n = 6 per group) were generated in mice using genetically engineered prostate cancer cells with inducible CHKA knockdown. Data were analyzed with χ2 tests, Cox regression analysis, and Kaplan-Meier methods. All statistical tests were two-sided. Results: CHKA expression was shown to be androgen regulated in cell lines, xenografts, and human tissue (log fold change from 6.75 to 6.59, P = .002) and was positively associated with tumor stage. CHKA binds directly to the ligand-binding domain (LBD) of AR, enhancing its stability. As such, CHKA is the first kinase identified as an AR chaperone. Inhibition of CHKA repressed the AR transcriptional program including pathways enriched for regulation of protein folding, decreased AR protein levels, and inhibited the growth of PCa cell lines, human PCa explants, and tumor xenografts. Conclusions: CHKA can act as an AR chaperone, providing, to our knowledge, the first evidence for kinases as molecular chaperones, making CHKA both a marker of tumor progression and a potential therapeutic target for PCa. PMID:26657335

  5. Targeting androgen receptor and JunD interaction for prevention of prostate cancer progression.

    Science.gov (United States)

    Mehraein-Ghomi, Farideh; Kegel, Stacy J; Church, Dawn R; Schmidt, Joseph S; Reuter, Quentin R; Saphner, Elizabeth L; Basu, Hirak S; Wilding, George

    2014-05-01

    Multiple studies show that reactive oxygen species (ROS) play a major role in prostate cancer (PCa) development and progression. Previously, we reported an induction of Spermidine/Spermine N(1) -Acetyl Transferase (SSAT) by androgen-activated androgen receptor (AR)-JunD protein complex that leads to over-production of ROS in PCa cells. In our current research, we identify small molecules that specifically block AR-JunD in this ROS-generating metabolic pathway. A high throughput assay based on Gaussia Luciferase reconstitution was used to identify inhibitors of the AR-JunD interaction. Selected hits were further screened using a fluorescence polarization competitor assay to eliminate those that bind to the AR Ligand Binding Domain (LBD), in order to identify molecules that specifically target events downstream to androgen activation of AR. Eleven molecules were selected for studies on their efficacy against ROS generation and growth of cultured human PCa cells by DCFH dye-oxidation assay and DNA fluorescence assay, respectively. In situ Proximity Ligation Assay (PLA), SSAT promoter-luciferase reporter assay, and western blotting of apoptosis and cell cycle markers were used to study mechanism of action of the lead compound. Selected lead compound GWARJD10 with EC(50) 10 μM against ROS production was shown to block AR-JunD interaction in situ as well as block androgen-induced SSAT gene expression at IC(50) 5 μM. This compound had no effect on apoptosis markers, but reduced cyclin D1 protein level. Inhibitor of AR-JunD interaction, GWARJD10 shows promise for prevention of progression of PCa at an early stage of the disease by blocking growth and ROS production. © 2014 Wiley Periodicals, Inc.

  6. Racial Variations in Prostate Cancer Molecular Subtypes and Androgen Receptor Signaling Reflect Anatomic Tumor Location.

    Science.gov (United States)

    Faisal, Farzana A; Sundi, Debasish; Tosoian, Jeffrey J; Choeurng, Voleak; Alshalalfa, Mohammed; Ross, Ashley E; Klein, Eric; Den, Robert; Dicker, Adam; Erho, Nicholas; Davicioni, Elai; Lotan, Tamara L; Schaeffer, Edward M

    2016-07-01

    Prostate cancer (PCa) subtypes based on ETS gene expression have been described. Recent studies suggest there are racial differences in tumor location, with PCa located anteriorly more often among African-American (AA) compared to Caucasian-American (CA) men. In this retrospective analysis of a multi-institutional cohort treated by radical prostatectomy (179 CA, 121 AA), we evaluated associations among molecular subtype, race, anatomic tumor location, and androgen receptor (AR) signaling. Subtype (m-ERG(+), m-ETS(+), m-SPINK1(+), or triple-negative) was determined using distribution-based outlier analysis. AR signaling was investigated using gene expression profiling of canonical AR targets. m-ERG(+) was more common in CA than AA men (47% vs 22%, pprostate cancer molecular subtypes, and tumor location. Location-specific differences in androgen regulation may further underlie these relationships. Copyright © 2015. Published by Elsevier B.V.

  7. A Novel Dietary Flavonoid Fisetin Inhibits Androgen Receptor Signaling and Tumor Growth in Athymic Nude Mice

    Science.gov (United States)

    Khan, Naghma; Asim, Mohammad; Afaq, Farrukh; Zaid, Mohammad Abu; Mukhtar, Hasan

    2010-01-01

    Androgen receptor (AR)–mediated signaling plays an important role in the development and progression of prostate cancer (PCa). Hormonal therapies, mainly with combinations of antiandrogens and androgen deprivation, are the mainstay treatment for advanced disease. However, emergence of androgen resistance largely due to inefficient antihormone action limits their therapeutic usefulness. Here, we report that fisetin, a novel dietary flavonoid, acts as a novel AR ligand by competing with the high-affinity androgen to interact with the ligand binding domain of AR. We show that this physical interaction results in substantial decrease in AR stability and decrease in amino-terminal/carboxyl-terminal (N-C) interaction of AR. This results in blunting of AR-mediated transactivation of target genes including prostate-specific antigen (PSA). In addition, treatment of LNCaP cells with fisetin decreased AR protein levels, in part, by decreasing its promoter activity and by accelerating its degradation. Fisetin also synergized with Casodex in inducing apoptosis in LNCaP cells. Treatment with fisetin in athymic nude mice implanted with AR-positive CWR22Rυ1 human PCa cells resulted in inhibition of tumor growth and reduction in serum PSA levels. These data identify fisetin as an inhibitor of AR signaling axis and suggest that it could be a useful chemopreventive and chemotherapeutic agent to delay progression of PCa. PMID:18922931

  8. Up-Regulation of Follistatin-Like 1 By the Androgen Receptor and Melanoma Antigen-A11 in Prostate Cancer.

    Science.gov (United States)

    Su, Shifeng; Parris, Amanda B; Grossman, Gail; Mohler, James L; Wang, Zengjun; Wilson, Elizabeth M

    2017-04-01

    High affinity androgen binding to the androgen receptor (AR) activates genes required for male sex differentiation and promotes the development and progression of prostate cancer. Human AR transcriptional activity involves interactions with coregulatory proteins that include primate-specific melanoma antigen-A11 (MAGE-A11), a coactivator that increases AR transcriptional activity during prostate cancer progression to castration-resistant/recurrent prostate cancer (CRPC). Microarray analysis and quantitative RT-PCR were performed to identify androgen-regulated MAGE-A11-dependent genes in LAPC-4 prostate cancer cells after lentivirus shRNA knockdown of MAGE-A11. Chromatin immunoprecipitation was used to assess androgen-dependent AR recruitment, and immunocytochemistry to localize an androgen-dependent protein in prostate cancer cells and tissue and in the CWR22 human prostate cancer xenograft. Microarray analysis of androgen-treated LAPC-4 prostate cancer cells indicated follistatin-like 1 (FSTL1) is up-regulated by MAGE-A11. Androgen-dependent up-regulation of FSTL1 was inhibited in LAPC-4 cells by lentivirus shRNA knockdown of AR or MAGE-A11. Chromatin immunoprecipitation demonstrated AR recruitment to intron 10 of the FSTL1 gene that contains a classical consensus androgen response element. Increased levels of FSTL1 protein in LAPC-4 cells correlated with higher levels of MAGE-A11 relative to other prostate cancer cells. FSTL1 mRNA levels increased in CRPC and castration-recurrent CWR22 xenografts in association with predominantly nuclear FSTL1. Increased nuclear localization of FSTL1 in prostate cancer was suggested by predominantly cytoplasmic FSTL1 in benign prostate epithelial cells and predominantly nuclear FSTL1 in epithelial cells in CRPC tissue and the castration-recurrent CWR22 xenograft. AR expression studies showed nuclear colocalization of AR and endogenous FSTL1 in response to androgen. AR and MAGE-A11 cooperate in the up-regulation of FSTL1 to

  9. The Androgen Receptor Bridges Stem Cell-Associated Signaling Nodes in Prostate Stem Cells

    Directory of Open Access Journals (Sweden)

    Alastair H. Davies

    2016-01-01

    Full Text Available The therapeutic potential of stem cells relies on dissecting the complex signaling networks that are thought to regulate their pluripotency and self-renewal. Until recently, attention has focused almost exclusively on a small set of “core” transcription factors for maintaining the stem cell state. It is now clear that stem cell regulatory networks are far more complex. In this review, we examine the role of the androgen receptor (AR in coordinating interactions between signaling nodes that govern the balance of cell fate decisions in prostate stem cells.

  10. Growth Inhibition by Testosterone in an Androgen Receptor Splice Variant-Driven Prostate Cancer Model.

    Science.gov (United States)

    Nakata, Daisuke; Nakayama, Kazuhide; Masaki, Tsuneo; Tanaka, Akira; Kusaka, Masami; Watanabe, Tatsuya

    2016-12-01

    Castration resistance creates a significant problem in the treatment of prostate cancer. Constitutively active splice variants of androgen receptor (AR) have emerged as drivers for resistance to androgen deprivation therapy, including the next-generation androgen-AR axis inhibitors abiraterone and enzalutamide. In this study, we describe the characteristics of a novel castration-resistant prostate cancer (CRPC) model, designated JDCaP-hr (hormone refractory). JDCaP-hr was established from an androgen-dependent JDCaP xenograft model after surgical castration. The expression of AR and its splice variants in JDCaP-hr was evaluated by immunoblotting and quantitative reverse transcription-polymerase chain reaction. The effects of AR antagonists and testosterone on JDCaP-hr were evaluated in vivo and in vitro. The roles of full-length AR (AR-FL) and AR-V7 in JDCaP-hr cell growth were evaluated using RNA interference. JDCaP-hr acquired a C-terminally truncated AR protein during progression from the parental JDCaP. The expression of AR-FL and AR-V7 mRNA was upregulated by 10-fold in JDCaP-hr compared with that in JDCaP, indicating that the JDCaP and JDCaP-hr models simulate castration resistance with some clinical features, such as overexpression of AR and its splice variants. The AR antagonist bicalutamide did not affect JDCaP-hr xenograft growth, and importantly, testosterone induced tumor regression. In vitro analysis demonstrated that androgen-independent prostate-specific antigen secretion and cell proliferation of JDCaP-hr were predominantly mediated by AR-V7. JDCaP-hr cell growth displayed a bell-shaped dependence on testosterone, and it was suppressed by physiological concentrations of testosterone. Testosterone induced rapid downregulation of both AR-FL and AR-V7 expression at physiological concentrations and suppressed expression of the AR target gene KLK3. Our findings support the clinical value of testosterone therapy, including bipolar androgen therapy, in the

  11. Prostate Cancer Cells in Different Androgen Receptor Status Employ Different Leucine Transporters.

    Science.gov (United States)

    Otsuki, Hideo; Kimura, Toru; Yamaga, Takashi; Kosaka, Takeo; Suehiro, Jun-Ichi; Sakurai, Hiroyuki

    2017-02-01

    Leucine stimulates cancer cell proliferation through the mTOR pathway, therefore, inhibiting leucine transporters may be a novel therapeutic target for cancer. L-type amino acid transporter (LAT) 1, a Na + -independent amino acid transporter, is highly expressed in many tumor cells. However, leucine transporter(s) in different stages of prostate cancer, particularly in the stages of castration resistance with androgen receptor (AR) expression, is unclear. LNCaP and DU145 and PC-3 cell lines were used as a model of androgen dependent, and metastatic prostate cancer. A new "LN-cr" cell line was established after culturing LNCaP cells for 6 months under androgen-free conditions, which is considered a model of castration resistant prostate cancer (CRPC) with androgen AR expression. The expression of leucine transporters was investigated with quantitative PCR and immunofluorescence. Uptake of 14 C Leucine was examined in the presence or absence of BCH (a pan-LAT inhibitor), JPH203 (an LAT1-specific inhibitor), or Na + . Cell growth was assessed with MTT assay. siRNA studies were performed to evaluate the indispensability of y + LAT2 on leucine uptake and cell viability in LN-cr. Cell viability showed a 90% decrease in the absence of leucine in all four cell lines. LNCaP cells principally expressed LAT3, and their leucine uptake was more than 90% Na + -independent. BCH, but not JPH203, inhibited leucine uptake, and cell proliferation (IC 50BCH :15 mM). DU145 and PC-3 cells predominantly expressed LAT1. Leucine uptake and cell growth were suppressed by BCH or JPH203 in a dose-dependent manner (IC 50BCH : ∼20 mM, IC 50JPH203 : ∼5 µM). In LN-cr cells, Na + -dependent uptake of leucine was 3.8 pmol/mgprotein/min, while, Na + -independent uptake was only 0.52 (P prostate cancer. Prostate 77:222-233, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Epigenomic Regulation of Androgen Receptor Signaling: Potential Role in Prostate Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Vito Cucchiara

    2017-01-01

    Full Text Available Androgen receptor (AR signaling remains the major oncogenic pathway in prostate cancer (PCa. Androgen-deprivation therapy (ADT is the principle treatment for locally advanced and metastatic disease. However, a significant number of patients acquire treatment resistance leading to castration resistant prostate cancer (CRPC. Epigenetics, the study of heritable and reversible changes in gene expression without alterations in DNA sequences, is a crucial regulatory step in AR signaling. We and others, recently described the technological advance Chem-seq, a method to identify the interaction between a drug and the genome. This has permitted better understanding of the underlying regulatory mechanisms of AR during carcinogenesis and revealed the importance of epigenetic modifiers. In screening for new epigenomic modifiying drugs, we identified SD-70, and found that this demethylase inhibitor is effective in CRPC cells in combination with current therapies. The aim of this review is to explore the role of epigenetic modifications as biomarkers for detection, prognosis, and risk evaluation of PCa. Furthermore, we also provide an update of the recent findings on the epigenetic key processes (DNA methylation, chromatin modifications and alterations in noncoding RNA profiles involved in AR expression and their possible role as therapeutic targets.

  13. Receptor tyrosine phosphatase R-PTP-alpha is tyrosine-phosphorylated and associated with the adaptor protein Grb2

    DEFF Research Database (Denmark)

    Su, J; Batzer, A; Sap, J

    1994-01-01

    Receptor tyrosine phosphatases (R-PTPases) have generated interest because of their suspected involvement in cellular signal transduction. The adaptor protein Grb2 has been implicated in coupling receptor tyrosine kinases to Ras. We report that a ubiquitous R-PTPase, R-PTP-alpha, is tyrosine......-phosphorylated and associated in vivo with the Grb2 protein. This association can be reproduced in stably and transiently transfected cells, as well as in vitro using recombinant Grb2 protein. Association requires the presence of an intact SH2 domain in Grb2, as well as tyrosine phosphorylation of R-PTP-alpha. This observation...... links a receptor tyrosine phosphatase with a key component of a central cellular signalling pathway and provides a basis for addressing R-PTP-alpha function....

  14. Amino acid containing thapsigargin analogues deplete androgen receptor protein via synthesis inhibition and induce the death of prostate cancer cells

    DEFF Research Database (Denmark)

    Griend, Donald J Vander; Antony, Lizamma; Dalrymple, Susan L

    2009-01-01

    There are quantitative and/or qualitative mechanisms allowing androgen receptor (AR) growth signaling in androgen ablation refractory prostate cancer cells. Regardless of the mechanism, agents that deplete AR protein expression prevent such AR growth signaling. Thapsigargin (TG) is a highly cell......-penetrant sequiterpene-lactone that once inside cells inhibits (IC(50), approximately 10 nmol/L) critically important housekeeping SERCA 2b calcium pumps in the endoplasmic reticulum. Using a series of five genetically diverse androgen ablation refractory human prostate cancer lines (LNCaP, LAPC-4, VCaP, MDA-PCa-2b......-specific proteases, such as prostate-specific antigen and prostate-specific membrane antigen, or cancer-specific proteases, such as fibroblast activation protein, so that toxicity of these prodrugs is selectively targeted to metastatic sites of prostate cancer. Based on these results, these prodrugs are undergoing...

  15. Obstructing Androgen Receptor Activation in Prostate Cancer Cells Through Post-translational Modification by NEDD8

    Science.gov (United States)

    2012-11-01

    FACS flow cytometer analysis . In addition, we will measure the steady state protein level of p53, p21, p27, and pRb. In the Jab1 silencing cell...affected by DHT treatment, and the endogenous AR level was not affected by Jab1 silencing. Interestingly, Western blot analysis of immunoprecipitated AR...Avantaggiati, and R. G. Pestell . 2003. Acetylation of androgen receptor enhances coactivator binding and promotes prostate cancer cell growth. Mol

  16. Nitric oxide generated by ionizing radiation and EGF is implicated in EGF receptor phosphorylation in A549 lung carcinoma cells

    International Nuclear Information System (INIS)

    Park, In Chul; Lee, Hyung Chahn; Rhee, Chang Hun; Hong, Seok Il

    2004-01-01

    Although it has been demonstrated that ionizing radiation (IR) control various cell functions in a different cell types, the mechanisms of its action via NO are not well understood. NO may potentially affect every type of mammalian cells, owing to its ubiquitous production and participate in the control of cell proliferation in a great variety of cell types. The epidermal growth factor (EGF) receptor is a transmembrane glycoprotein of Mr 170,000. When EGF binds to its receptor, the receptor is dimerized and autophosphorylated at the carboxyl-terminal tyrosine 992, 1608, 1086, 1148 and 1173. This phosphorylated receptor initiates a series of signal tranduction events through interacting proteins of SH2 family including Shc, Grb2 and Sos, which in turn trigger ativation of MAPK cascades. Although the number of signaling events mediated by IR-induced NO is growing, it is still unclear how NO activate cellular signaling events. Thus, we examined the effect of NO on cellular phosphorylation and found that NO was produced by ionizing radiation in A549 lung adenocarcinoma cells and enhances the unique tyrosine phosphorylation on EGF receptor

  17. Implication of androgen receptor in urinary bladder cancer: a critical mini review.

    Science.gov (United States)

    Rahmani, Arshad H; Alzohairy, Mohammad; Babiker, Ali Yousif Y; Khan, Amjad A; Aly, Salah M; Rizvi, Moshahid A

    2013-01-01

    Cancer is probably the most dreaded disease of mankind and the bladder cancer is the fifth most common type of cancer worldwide. It is a major cause of cancer morbidity and mortality. From amongst the bladder cancer, the Transitional Cell Carcinoma (TCC) is the most prevalent cancer of the bladder and accounts for 90% of all bladder cancer cases. Despite such a high prevalence, the molecular mechanism involved in the induction of bladder carcinoma and its progression are poorly understood. Tumorigenesis and tumor progression of bladder carcinomas are thought to result from the accumulation of multiple genetic alterations. The Androgen Receptor (AR) gene is located on the q arm of X chromosome (q11-12) and considered as a ligand-inducible transcription factor that regulates target gene expression. The Androgen plays a vital role in the development and maintenance of the normal urinary bladder. The AR is also involved in the development and progression of urinary bladder carcinoma, which is the most common type of carcinoma. Mutation in AR alters the ligand binding ability that may cause the progression and development of bladder cancer. Tumorigenesis and tumor progression are thought to result from changes in the function of hormonal receptor gene. The accumulation of the changes in AR expressions, determines the tumor's phenotype and ultimately the patient's clinical outcome. The early detection of which may help in management and prediction, how will it behave and respond to the therapeutic regimen. The present review aimed to study the mechanism and alteration of AR gene that play a vital role in the tumorIgenesis of bladder carcinoma.

  18. Quantitation of multisite EGF receptor phosphorylation using mass spectrometry and a novel normalization approach

    DEFF Research Database (Denmark)

    Erba, Elisabetta Boeri; Matthiesen, Rune; Bunkenborg, Jakob

    2007-01-01

    Using stable isotope labeling and mass spectrometry, we performed a sensitive, quantitative analysis of multiple phosphorylation sites of the epidermal growth factor (EGF) receptor. Phosphopeptide detection efficiency was significantly improved by using the tyrosine phosphatase inhibitor sodium p...

  19. Expression of Androgen Receptor Is Negatively Regulated By p53

    Directory of Open Access Journals (Sweden)

    Fatouma Alimirah

    2007-12-01

    Full Text Available Increased expression of androgen receptor (AR in prostate cancer (PC is associated with transition to androgen independence. Because the progression of PC to advanced stages is often associated with the loss of p53 function, we tested whether the p53 could regulate the expression of AR gene. Here we report that p53 negatively regulates the expression of AR in prostate epithelial cells (PrECs. We found that in LNCaP human prostate cancer cells that express the wild-type p53 and AR and in human normal PrECs, the activation of p53 by genotoxic stress or by inhibition of p53 nuclear export downregulated the expression of AR. Furthermore, forced expression of p53 in LNCaP cells decreased the expression of AR. Conversely, knockdown of p53 expression in LNCaP cells increased the AR expression. Consistent with the negative regulation of AR expression by p53, the p53-null HCT116 cells expressed higher levels of AR compared with the isogenic HCT116 cells that express the wildtype p53. Moreover, we noted that in etoposide treated LNCaP cells p53 bound to the promoter region of the AR gene, which contains a potential p53 DNA-binding consensus sequence, in chromatin immunoprecipitation assays. Together, our observations provide support for the idea that the loss of p53 function in prostate cancer cells contributes to increased expression of AR.

  20. The androgen receptor controls expression of the cancer-associated sTn antigen and cell adhesion through induction of ST6GalNAc1 in prostate cancer

    Science.gov (United States)

    Munkley, Jennifer; Oltean, Sebastian; Vodák, Daniel; Wilson, Brian T.; Livermore, Karen E.; Zhou, Yan; Star, Eleanor; Floros, Vasileios I.; Johannessen, Bjarne; Knight, Bridget; McCullagh, Paul; McGrath, John; Crundwell, Malcolm; Skotheim, Rolf I.; Robson, Craig N.; Leung, Hing Y.; Harries, Lorna W.; Rajan, Prabhakar; Mills, Ian G.; Elliott, David J.

    2015-01-01

    Patterns of glycosylation are important in cancer, but the molecular mechanisms that drive changes are often poorly understood. The androgen receptor drives prostate cancer (PCa) development and progression to lethal metastatic castration-resistant disease. Here we used RNA-Seq coupled with bioinformatic analyses of androgen-receptor (AR) binding sites and clinical PCa expression array data to identify ST6GalNAc1 as a direct and rapidly activated target gene of the AR in PCa cells. ST6GalNAc1 encodes a sialytransferase that catalyses formation of the cancer-associated sialyl-Tn antigen (sTn), which we find is also induced by androgen exposure. Androgens induce expression of a novel splice variant of the ST6GalNAc1 protein in PCa cells. This splice variant encodes a shorter protein isoform that is still fully functional as a sialyltransferase and able to induce expression of the sTn-antigen. Surprisingly, given its high expression in tumours, stable expression of ST6GalNAc1 in PCa cells reduced formation of stable tumours in mice, reduced cell adhesion and induced a switch towards a more mesenchymal-like cell phenotype in vitro. ST6GalNAc1 has a dynamic expression pattern in clinical datasets, being significantly up-regulated in primary prostate carcinoma but relatively down-regulated in established metastatic tissue. ST6GalNAc1 is frequently upregulated concurrently with another important glycosylation enzyme GCNT1 previously associated with prostate cancer progression and implicated in Sialyl Lewis X antigen synthesis. Together our data establishes an androgen-dependent mechanism for sTn antigen expression in PCa, and are consistent with a general role for the androgen receptor in driving important coordinate changes to the glycoproteome during PCa progression. PMID:26452038

  1. Novel, non-steroidal, selective androgen receptor modulators (SARMs) with anabolic activity in bone and muscle and improved safety profile.

    Science.gov (United States)

    Rosen, J; Negro-Vilar, A

    2002-03-01

    A novel approach to the treatment of osteoporosis in men, and possibly women, is the development of selective androgen receptor modulators (SARMs) that can stimulate formation of new bone with substantially diminished proliferative activity in the prostate, as well as reduced virilizing activity in women. Over the last several years, we have developed a program to discover and develop novel, non-steroidal, orally-active selective androgen receptor modulators (SARMs) that provide improved therapeutic benefits and reduce risk and side effects. In recent studies, we have used a skeletally mature orchiectomized (ORX) male rat as an animal model of male hypogonadism for assessing the efficacy of LGD2226, a nonsteroidal, non-aromatizable, and non-5alpha-reducible SARM. We assessed the activity of LGD2226 on bone turnover, bone mass and bone strength, and also evaluated the effects exerted on classic androgen-dependent targets, such as prostate, seminal vesicles and muscle. A substantial loss of bone density was observed in ORX animals, and this loss was prevented by SARMs, as well as standard androgens. Biochemical markers of bone turnover revealed an early increase of bone resorption in androgen-deficient rats that was repressed in ORX animals treated with the oral SARM, LGD2226, during a 4-month treatment period. Differences in architectural properties and bone strength were detected by histomorphometric and mechanical analyses, demonstrating beneficial effects of LGD2226 on bone quality in androgen-deficient rats. Histomorphometric analysis of cortical bone revealed distinct anabolic activity of LGD2226 in periosteal bone. LGD2226 was able to prevent bone loss and maintain bone quality in ORX rats by stimulating bone formation, while also inhibiting bone turnover. LGD2226 also exerted anabolic activity on the levator ani muscle. Taken together, these results suggest that orally-active, non-steroidal SARMs may be useful therapeutics for both muscle and bone in elderly

  2. A selective androgen receptor modulator that reduces prostate tumor size and prevents orchidectomy-induced bone loss in rats.

    Science.gov (United States)

    Allan, George; Lai, Muh-Tsann; Sbriscia, Tifanie; Linton, Olivia; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Dodds, Robert; Fiordeliso, James; Lanter, James; Sui, Zhihua; Lundeen, Scott

    2007-01-01

    The pharmacological activity of JNJ-26146900 is described. JNJ-26146900 is a nonsteroidal androgen receptor (AR) ligand with tissue-selective activity in rats. The compound was evaluated in in vitro and in vivo models of AR activity. It binds to the rat AR with a K(i) of 400nM and acts as a pure androgen antagonist in an in vitro cell-based assay. Its in vitro profile is similar to the androgen antagonist bicalutamide (Casodex). In intact rats, JNJ-26146900 reduces ventral prostate weight with an oral potency (ED(50)) of 20-30mg/kg, again comparable to that of bicalutamide. JNJ-26146900 prevented prostate tumor growth in the Dunning rat model, maximally inhibiting growth at a dose of 10mg/kg. It slowed tumor growth significantly in a CWR22-LD1 mouse xenograft model of human prostate cancer. It was tested in aged male rats for its ability to prevent bone loss and loss of lean body mass following orchidectomy. After 6 weeks of dosing, bone volume decreased by 33% in orchidectomized versus intact vehicle-treated rats with a probability (P) of less than 0.05, as measured by micro-computerized tomography analysis. At a dose of 30mg/kg, JNJ-26146900 significantly reduced castration-induced tibial bone loss as indicated by the following parameters: bone volume, trabecular connectivity, trabecular number and spacing between trabeculae. Bone mineral density decreased from 229+/-34mg/cm(3) of hydroxyapatite to 166+/-26mg/cm(3) following orchidectomy, and was maintained at 194+/-20mg/cm(3) with JNJ-26146900 treatment (Pselective androgen receptor modulators (SARMs) have the potential for anabolic effects on bone and muscle while maintaining therapeutic efficacy in prostate cancer.

  3. Androgen receptor levels during progression of prostate cancer in the transgenic adenocarcinoma of mouse prostate model

    Directory of Open Access Journals (Sweden)

    Krisna Murti

    2010-02-01

    Full Text Available Aim To construct tissue microarrays (TMAs that consisted of prostate tumours from the transgenic adenocarcinoma of mouse prostate (TRAMP mice and non-transgenic murine prostates and to assess androgen receptor (AR levels during progression of prostate cancer in TRAMP mice by immunohistochemistry.Methods Haematoxylin and eosin (H&E sections from the ventral and dorso-lateral prostate lobes of non-transgenic, intact TRAMP and castrated TRAMP were used to demarcate regions of interest for TMAs construction. The samples on TMAs were used to evaluate AR expression using video image analysis (VIA.Results AR was expressed during cancer progression, but AR levels were reduced or absent in late stage disease. Furthermore, when AR levels were compared in tumours from intact and castrate animals, a significant increase in AR levels was observed following androgen ablation.Conclusion Similar to clinical prostate cancer, in the TRAMP model, prostate tumours evolve mechanisms to maintain AR expression and AR responsive gene pathways following castration to facilitate continued tumour growth. (Med J Indones 2010; 19:5-13Keywords : androgen ablation therapy, tissue microarrays, haematoxylin and eosin, video image analysis

  4. Immunohistochemical localization of androgen receptor in rat caput epididymis during postnatal development

    Directory of Open Access Journals (Sweden)

    Sema Timurkaan

    2011-09-01

    Full Text Available Objectives: The aim of this study was to investigate the developmental pattern of androgen receptor (AR in caput epididymis.Materials and methods: In this study three randomly selected rats were sacrificed at ages 21, 56, 90 and 120 days old. All male rats were anesthetized with ethyl ether before killing. Then, the caput epididymides were removed and fixed in Bouin’s fixative at +4°C for 36 hour. Afterwards the tissue samples were embedded in paraffin for routine histological methods. Later the tissues were sectioned at 5μm and mounted on poly-L-lysin-coated slides. To solve the antigen masking problem, we performed microwave stimulated antigen retrieval technique before the immunohistochemical staining. Avidin-Biotin-Peroxidase Complex (ABC method was applied for immunohistochemical staining.Results: In all age groups of rats studied, positive immunohistochemical staining for the AR appeared in nuclei of epididymal cells. The staining intensity of AR positive cells did not change depending on age. In caput epididymis, immunostainable AR was found in tubular epithelial cells (principal cells, basal cells and apical cells and peritubular smooth muscle cells. The AR staining in the epithelial cells appeared to be stronger than in the peritubular smooth muscle cells. In the epithelial cells; staining intensity was stronger in principal cells than in basal cells and apical cells.Conclusion: Staining intensity of AR positive epididymal cells irrespective of age indicated the necessity of androgens for postnatal differentiation and maintaining the structure of the epididymis. Stronger staining intensity in principal cells suggested that principal cells are more sensitive to androgen stimulation. J Clin Exp Invest 2011; 2 (3: 260-266.

  5. Resistance to EGF receptor inhibitors in glioblastoma mediated by phosphorylation of the PTEN tumor suppressor at tyrosine 240.

    Science.gov (United States)

    Fenton, Tim R; Nathanson, David; Ponte de Albuquerque, Claudio; Kuga, Daisuke; Iwanami, Akio; Dang, Julie; Yang, Huijun; Tanaka, Kazuhiro; Oba-Shinjo, Sueli Mieko; Uno, Miyuki; Inda, Maria del Mar; Wykosky, Jill; Bachoo, Robert M; James, C David; DePinho, Ronald A; Vandenberg, Scott R; Zhou, Huilin; Marie, Suely K N; Mischel, Paul S; Cavenee, Webster K; Furnari, Frank B

    2012-08-28

    Glioblastoma multiforme (GBM) is the most aggressive of the astrocytic malignancies and the most common intracranial tumor in adults. Although the epidermal growth factor receptor (EGFR) is overexpressed and/or mutated in at least 50% of GBM cases and is required for tumor maintenance in animal models, EGFR inhibitors have thus far failed to deliver significant responses in GBM patients. One inherent resistance mechanism in GBM is the coactivation of multiple receptor tyrosine kinases, which generates redundancy in activation of phosphoinositide-3'-kinase (PI3K) signaling. Here we demonstrate that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) tumor suppressor is frequently phosphorylated at a conserved tyrosine residue, Y240, in GBM clinical samples. Phosphorylation of Y240 is associated with shortened overall survival and resistance to EGFR inhibitor therapy in GBM patients and plays an active role in mediating resistance to EGFR inhibition in vitro. Y240 phosphorylation can be mediated by both fibroblast growth factor receptors and SRC family kinases (SFKs) but does not affect the ability of PTEN to antagonize PI3K signaling. These findings show that, in addition to genetic loss and mutation of PTEN, its modulation by tyrosine phosphorylation has important implications for the development and treatment of GBM.

  6. The clinical and molecular spectrum of androgen insensitivity syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Hiort, O.; Sinnecker, G.H.G.; Holterhus, P.M.; Nitsche, E.M.; Kruse, K. [Medical Univ. of Luebeck (Germany)

    1996-05-03

    Androgen insensitivity syndromes (AIS) are due to end-organ resistance to androgenic steroids in males leading to defective virilization of the external genitalia. The phenotype encompasses a wide array of genital ambiguity and may range from completely female to undervirilized but unequivocally male with infertility. This disorder is caused by mutations of the androgen receptor and is an X-linked recessive trait. We have studied 47 patients with AIS and have characterized the underlying molecular abnormality in the androgen receptor gene. Twenty patients had complete AIS and twenty-seven had partial AIS. Of the latter, 11 were of predominantly female phenotypic appearance and gender was assigned accordingly, while 16 were raised as males. Within the group of complete AIS, two patients had gross deletions within the gene, one had a small deletion, and one had an insertion. In the other patients with complete AIS, as well as all individuals with partial AIS, single nucleotide substitutions within the coding region were detected, each leading to an amino acid alteration. Seven codons were involved in more than one mutation in different cases. In addition, in one patient with spinal and bulbar muscular atrophy, an elongation of a glutamine-repeat was characterized. We conclude that mutations in the androgen receptor gene may be present throughout the whole coding region. However, our study provides evidence that several mutational hot spots exist. 18 refs., 2 figs.

  7. Characterization of Aromatase Expression in the Adult Male and Female Mouse Brain. I. Coexistence with Oestrogen Receptors α and β, and Androgen Receptors

    Science.gov (United States)

    Stanić, Davor; Dubois, Sydney; Chua, Hui Kheng; Tonge, Bruce; Rinehart, Nicole; Horne, Malcolm K.; Boon, Wah Chin

    2014-01-01

    Aromatase catalyses the last step of oestrogen synthesis. There is growing evidence that local oestrogens influence many brain regions to modulate brain development and behaviour. We examined, by immunohistochemistry, the expression of aromatase in the adult male and female mouse brain, using mice in which enhanced green fluorescent protein (EGFP) is transcribed following the physiological activation of the Cyp19A1 gene. EGFP-immunoreactive processes were distributed in many brain regions, including the bed nucleus of the stria terminalis, olfactory tubercle, medial amygdaloid nucleus and medial preoptic area, with the densest distributions of EGFP-positive cell bodies in the bed nucleus and medial amygdala. Differences between male and female mice were apparent, with the density of EGFP-positive cell bodies and fibres being lower in some brain regions of female mice, including the bed nucleus and medial amygdala. EGFP-positive cell bodies in the bed nucleus, lateral septum, medial amygdala and hypothalamus co-expressed oestrogen receptor (ER) α and β, or the androgen receptor (AR), although single-labelled EGFP-positive cells were also identified. Additionally, single-labelled ERα−, ERβ- or AR-positive cell bodies often appeared to be surrounded by EGFP-immunoreactive nerve fibres/terminals. The widespread distribution of EGFP-positive cell bodies and fibres suggests that aromatase signalling is common in the mouse brain, and that locally synthesised brain oestrogens could mediate biological effects by activating pre- and post-synaptic oestrogen α and β receptors, and androgen receptors. The higher number of EGFP-positive cells in male mice may indicate that the autocrine and paracrine effects of oestrogens are more prominent in males than females. PMID:24646567

  8. Effects of cypermethrin on the ligand-independent interaction between androgen receptor and steroid receptor coactivator-1

    International Nuclear Information System (INIS)

    Pan, Chen; Liu, Ya-Peng; Li, Yan-Fang; Hu, Jin-Xia; Zhang, Jin-Peng; Wang, Hong-Mei; Li, Jing; Xu, Li-Chun

    2012-01-01

    The pyrethroid insecticide, cypermethrin has been considered as an environmental anti-androgen by interfering with the androgen receptor (AR) transactivation. In order to clarify the effects of cypermethrin on the ligand-independent interaction between the AR and SRC-1, the mammalian two-hybrid assay has been developed in the study. The AR N-terminal domain 1–660 amino acid residues were subcloned into the plasmid pVP16 to construct the vector pVP16-ARNTD. The SRC-1 C-terminal domain 989–1240 amino acid residues were subcloned into the plasmid pM to construct the vector pM-SRC-1. The fusion vectors pVP16-ARNTD, pM-SRC-1 and the pG5CAT Reporter Vector were cotransfected into the CV-1 cells. The AR AF1 interacted with SRC-1 in the absence of exogenous ligand 5α-dihydrotestosterone (DHT). Furthermore, DHT did not enhance the interaction between AR AF-1 and SRC-1 at the concentrations from 10 −10 M to 10 −8 M. Cypermethrin inhibited the interaction between the AR AF1 and SRC-1, and the significant reduction was detected at the concentration of 10 −5 M. It is suggested that the interaction between the AR AF1 and SRC-1 is ligand-independent. Cypermethrin inhibits AR activity by disrupting the ligand-independent AR–SRC-1 interaction.

  9. Differential effects of genistein on prostate cancer cells depend on mutational status of the androgen receptor.

    Directory of Open Access Journals (Sweden)

    Abeer M Mahmoud

    Full Text Available Blocking the androgen receptor (AR activity is the main goal of therapies for advanced prostate cancer (PCa. However, relapse with a more aggressive, hormone refractory PCa arises, which harbors restored AR activity. One mechanism of such reactivation occurs through acquisition of AR mutations that enable its activation by various steroidal and non-steroidal structures. Thus, natural and chemical compounds that contribute to inappropriate (androgen-independent activation of the AR become an area of intensive research. Here, we demonstrate that genistein, a soy phytoestrogen binds to both the wild and the Thr877Ala (T877A mutant types of AR competitively with androgen, nevertheless, it exerts a pleiotropic effect on PCa cell proliferation and AR activity depending on the mutational status of the AR. Genistein inhibited, in a dose-dependent way, cell proliferation and AR nuclear localization and expression in LAPC-4 cells that have wild AR. However, in LNCaP cells that express the T877A mutant AR, genistein induced a biphasic effect where physiological doses (0.5-5 µmol/L stimulated cell growth and increased AR expression and transcriptional activity, and higher doses induced inhibitory effects. Similar biphasic results were achieved in PC-3 cells transfected with AR mutants; T877A, W741C and H874Y. These findings suggest that genistein, at physiological concentrations, potentially act as an agonist and activate the mutant AR that can be present in advanced PCa after androgen ablation therapy.

  10. The role of androgen receptor activity mediated by the CAG repeat polymorphism in the pathogenesis of PCOS.

    Science.gov (United States)

    Baculescu, N

    2013-03-15

    Polycystic ovary syndrome (PCOS), one of the most common and complex endocrine disorders affecting up to 15 % of reproductive age women, is considered a predominantly hyperandrogenic syndrome according to the Androgen Excess Society. It is generally accepted that androgens determine the characteristic features of PCOS; in this context, a hyperactive androgen receptor (AR) at the levels of the GnRH pulse generator in the hypothalamus and at the granulosa cells in the ovary, skeletal muscle or adipocytes senses initially normal testosterone and dihydrotestosterone as biochemical hyperandrogenism and might be a crucial connection between the vicious circles of the PCOS pathogenesis. Polymorphism of the AR gene has been associated with different androgen pattern diseases. Several studies have demonstrated an association between AR with increased activity encoded by shorter CAG repeat polymorphism in the exon 1 of the AR gene and PCOS, although there are conflicting results in this field. The phenomenon is more complex because the AR activity is determined by the epigenetic effect of X chromosome inactivation (XCI). Moreover, we must evaluate the AR as a dynamic heterocomplex, with a large number of coactivators and corepressors that are essential to its function, thus mediating tissue-specific effects. In theory, any of these factors could modify the activity of AR, which likely explains the inconsistent results obtained when this activity was quantified by only the CAG polymorphism in PCOS.

  11. Synergic prodegradative activity of Bicalutamide and trehalose on the mutant androgen receptor responsible for spinal and bulbar muscular atrophy

    NARCIS (Netherlands)

    Giorgetti, Elise; Rusmini, Paola; Crippa, Valeria; Cristofani, Riccardo; Boncoraglio, Alessandra; Cicardi, Maria E.; Galbiati, Mariarita; Poletti, Angelo

    2015-01-01

    Spinal and bulbar muscular atrophy (SBMA) is an X-linked motoneuron disease due to a CAG triplet-repeat expansion in the androgen receptor (AR) gene, which is translated into an elongated polyglutamine (polyQ) tract in AR protein (ARpolyQ). ARpolyQ toxicity is activated by the AR ligand testosterone

  12. A study of the prostate, androgens and sexual activity of male rats

    Directory of Open Access Journals (Sweden)

    Garcia Luis I

    2007-03-01

    Full Text Available Abstract Background The prostate is a sexual gland that produces important substances for the potency of sperm to fertilize eggs within the female reproductive tract, and is under complex endocrine control. Taking advantage of the peculiar behavioral pattern of copulating male rats, we developed experimental paradigms to determine the influence of sexual behavior on the level of serum testosterone, prostate androgen receptors, and mRNA for androgen receptors in male rats displaying up to four consecutive ejaculations. Methods The effect of four consecutive ejaculations was investigated by determining levels of (i testosterone in serum by solid phase RIA, (ii androgen receptors at the ventral prostate with Western Blots, and (iii androgen receptors-mRNA with RT-PCR. Data were analyzed with a one-way ANOVA followed by a post hoc application of Dunnett's test if required. Results The constant execution of sexual behavior did not produce any change in the weight of the ventral prostate. Serum testosterone increased after the second ejaculation, and remained elevated even after four ejaculations. The androgen receptor at the ventral prostate was higher after the first to third ejaculations, but returned suddenly to baseline levels after the fourth ejaculation. The level of mRNA increased after the first ejaculation, continued to increase after the second, and reached the highest peak after the third ejaculation; however, it returned suddenly to baseline levels after the fourth ejaculation. Conclusion Four consecutive ejaculations by sexually experienced male rats had important effects on the physiological responses of the ventral prostate. Fast responses were induced as a result of sexual behavior that involved an increase and decrease in androgen receptors after one and four ejaculations, respectively. However, a progressive response was observed in the elevation of mRNA for androgen receptors, which also showed a fast decrease after four

  13. Protein kinase D1 (PKD1) influences androgen receptor (AR) function in prostate cancer cells

    International Nuclear Information System (INIS)

    Mak, Paul; Jaggi, Meena; Syed, Viqar; Chauhan, Subhash C.; Hassan, Sazzad; Biswas, Helal; Balaji, K.C.

    2008-01-01

    Protein kinase D1 (PKD1), founding member of PKD protein family, is down-regulated in advanced prostate cancer (PCa). We demonstrate that PKD1 and androgen receptor (AR) are present as a protein complex in PCa cells. PKD1 is associated with a transcriptional complex which contains AR and promoter sequence of the Prostate Specific Antigen (PSA) gene. Ectopic expression of wild type PKD1 and the kinase dead mutant PKD1 (K628W) attenuated the ligand-dependent transcriptional activation of AR in prostate cancer cells and yeast cells indicating that PKD1 can affect AR transcription activity, whereas knocking down PKD1 enhanced the ligand-dependent transcriptional activation of AR. Co-expression of kinase dead mutant with AR significantly inhibited androgen-mediated cell proliferation in both LNCaP and DU145 PC cells. Our data demonstrate for the first time that PKD1 can influence AR function in PCa cells

  14. Muscle Dysfunction in Androgen Deprivation: Role of Ryanodine Receptor

    Science.gov (United States)

    2016-11-01

    reversible pharmacological treatment is a key therapeutic goal in prostate cancer patients. This life prolonging treatment is accompanied by the adverse... reversible pharmacological treatment, is a key therapeutic goal of androgen deprivation therapies (ADT) used in patients with androgen-dependent...gel improves sexual function, mood, muscle strength, and body composition parameters in hypogonadal men. J Clin Endocrinol Metab. Aug 2000;85(8):2839

  15. N-Aryl-oxazolidin-2-imine Muscle Selective Androgen Receptor Modulators Enhance Potency through Pharmacophore Reorientation

    Energy Technology Data Exchange (ETDEWEB)

    Nirschl, Alexandra A.; Zou, Yan; Krystek, Jr., Stanley R.; Sutton, James C.; Simpkins, Ligaya M.; Lupisella, John A.; Kuhns, Joyce E.; Seethala, Ramakrishna; Golla, Rajasree; Sleph, Paul G.; Beehler, Blake C.; Grover, Gary J.; Egan, Donald; Fura, Aberra; Vyas, Viral P.; Li, Yi-Xin; Sack, John S.; Kish, Kevin F.; An, Yongmi; Bryson, James A.; Gougoutas, Jack Z.; DiMarco, John; Zahler, Robert; Ostrowski, Jacek; Hamann, Lawrence G.; (BMS)

    2010-11-09

    A novel selective androgen receptor modulator (SARM) scaffold was discovered as a byproduct obtained during synthesis of our earlier series of imidazolidin-2-ones. The resulting oxazolidin-2-imines are among the most potent SARMs known, with many analogues exhibiting sub-nM in vitro potency in binding and functional assays. Despite the potential for hydrolytic instability at gut pH, compounds of the present class showed good oral bioavailability and were highly active in a standard rodent pharmacological model.

  16. Regulation of uterine progesterone receptors by the nonsteroidal anti-androgen hydroxyflutamide

    International Nuclear Information System (INIS)

    Chandrasekhar, Y.; Armstrong, D.T.

    1991-01-01

    The authors have recently reported that the anti-androgen hydroxyflutamide causes delayed implantation and exhibits antideciduogenic activity in the rat. The present experiments were conducted to examine whether hydroxyflutamide binds to the uterine progesterone receptors and/or alters the progesterone binding sites in the uterus. Cytosol and nuclear fractions from decidualized rat uterus were incubated with [3H]-R5020 without or with increasing concentrations of radioinert R5020, RU486, dihydrotestosterone, or hydroxyflutamide. From the log-dose inhibition curves, the relative binding affinity of both hydroxyflutamide and dihydrotestosterone was less than 0.1% and 2%, compared with R5020 (100%) for displacing [3H]-R5020 bound to uterine cytosol and nuclear fractions, respectively. Injection of estradiol-17 beta (1 microgram/rat) to ovariectomized prepubertal rats induced a 1.85-fold increase in uterine weight by 24 h. Hydroxyflutamide at 2.5 or 5.0 mg did not significantly alter the estrogen-induced increase in uterine weight. Compared to vehicle alone, estrogen induced an approximately 5-fold increase in uterine cytosolic progesterone binding sites. Hydroxyflutamide at both 2.5- and 5.0-mg doses significantly attenuated the estrogen-induced elevation in uterine progesterone binding sites. These studies demonstrate that hydroxyflutamide does not bind with high affinity to progesterone receptors, but suppresses the estrogen-induced elevation in progesterone receptor levels in the uterus

  17. Network analysis of an in vitro model of androgen-resistance in prostate cancer

    International Nuclear Information System (INIS)

    Detchokul, Sujitra; Elangovan, Aparna; Crampin, Edmund J.; Davis, Melissa J.; Frauman, Albert G.

    2015-01-01

    The development of androgen resistance is a major limitation to androgen deprivation treatment in prostate cancer. We have developed an in vitro model of androgen-resistance to characterise molecular changes occurring as androgen resistance evolves over time. Our aim is to understand biological network profiles of transcriptomic changes occurring during the transition to androgen-resistance and to validate these changes between our in vitro model and clinical datasets (paired samples before and after androgen-deprivation therapy of patients with advanced prostate cancer). We established an androgen-independent subline from LNCaP cells by prolonged exposure to androgen-deprivation. We examined phenotypic profiles and performed RNA-sequencing. The reads generated were compared to human clinical samples and were analysed using differential expression, pathway analysis and protein-protein interaction networks. After 24 weeks of androgen-deprivation, LNCaP cells had increased proliferative and invasive behaviour compared to parental LNCaP, and its growth was no longer responsive to androgen. We identified key genes and pathways that overlap between our cell line and clinical RNA sequencing datasets and analysed the overlapping protein-protein interaction network that shared the same pattern of behaviour in both datasets. Mechanisms bypassing androgen receptor signalling pathways are significantly enriched. Several steroid hormone receptors are differentially expressed in both datasets. In particular, the progesterone receptor is significantly differentially expressed and is part of the interaction network disrupted in both datasets. Other signalling pathways commonly altered in prostate cancer, MAPK and PI3K-Akt pathways, are significantly enriched in both datasets. The overlap between the human and cell-line differential expression profiles and protein networks was statistically significant showing that the cell-line model reproduces molecular patterns observed in

  18. Testosterone treatment increases androgen receptor and aromatase gene expression in myotubes from patients with PCOS and controls, but does not induce insulin resistance.

    Science.gov (United States)

    Eriksen, Mette Brandt; Glintborg, Dorte; Nielsen, Michael Friberg Bruun; Jakobsen, Marianne Antonius; Brusgaard, Klaus; Tan, Qihua; Gaster, Michael

    2014-09-05

    Polycystic ovary syndrome (PCOS) is associated with insulin resistance and increased risk of type 2 diabetes. Skeletal muscle is the major site of insulin mediated glucose disposal and the skeletal muscle tissue is capable to synthesize, convert and degrade androgens. Insulin sensitivity is conserved in cultured myotubes (in vitro) from patients with PCOS, but the effect of testosterone on this insulin sensitivity is unknown. We investigated the effect of 7days testosterone treatment (100nmol/l) on glucose transport and gene expression levels of hormone receptors and enzymes involved in the synthesis and conversion of testosterone (HSD17B1, HSD17B2, CYP19A1, SRD5A1-2, AR, ER-α, HSD17B6 and AKR1-3) in myotubes from ten patients with PCOS and ten matched controls. Testosterone treatment significantly increased aromatase and androgen receptor gene expression levels in patients and controls. Glucose transport in myotubes was comparable in patients with PCOS vs. controls and was unchanged by testosterone treatment (p=0.21 PCOS vs. controls). These results suggest that testosterone treatment of myotubes increases the aromatase and androgen receptor gene expression without affecting insulin sensitivity and if testosterone is implicated in muscular insulin resistance in PCOS, this is by and indirect mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. In vivo imaging of brain androgen receptors in rats: a [18F]FDHT PET study

    International Nuclear Information System (INIS)

    Khayum, M.A.; Doorduin, J.; Antunes, I.F.; Kwizera, C.; Zijlma, R.; Boer, J.A. den; Dierckx, R.A.J.O.; Vries, E.F.J. de

    2015-01-01

    Introduction: Steroid hormones like androgens play an important role in the development and maintenance of several brain functions. Androgens can act through androgen receptors (AR) in the brain. This study aims to demonstrate the feasibility of positron emission tomography (PET) with 16β-[ 18 F]fluoro-5α-dihydrotestosterone ([ 18 F]FDHT) to image AR expression in the brain. Methods: Male Wistar rats were either orchiectomized to inhibit endogenous androgen production or underwent sham-surgery. Fifteen days after surgery, rats were subjected to a 90-min dynamic [ 18 F]FDHT PET scan with arterial blood sampling. In a subset of orchiectomized rats, 1 mg/kg dihydrotestosterone was co-injected with the tracer in order to saturate the AR. Plasma samples were analyzed for the presence of radioactive metabolites by radio-TLC. Pharmacokinetic modeling was performed to quantify brain kinetics of the tracer. After the PET scan, the animals were terminated for ex-vivo biodistribution. Results: PET imaging and ex vivo biodistribution studies showed low [ 18 F]FDHT uptake in all brain regions, except pituitary. [ 18 F]FDHT uptake in the surrounding cranial bones was high and increased over time. [ 18 F]FDHT was rapidly metabolized in rats. Metabolism was significantly faster in orchiectomized rats than in sham-orchiectomized rats. Quantitative analysis of PET data indicated substantial spill-over of activity from cranial bones into peripheral brain regions, which prevented further analysis of peripheral brain regions. Logan graphical analysis and kinetic modeling using 1- and 2-tissue compartment models showed reversible and homogenously distributed tracer uptake in central brain regions. [ 18 F]FDHT uptake in the brain could not be blocked by endogenous androgens or administration of dihydrotestosterone. Conclusion: The results of this study indicate that imaging of AR availability in rat brain with [ 18 F]FDHT PET is not feasible. The low AR expression in the brain, the

  20. The role of testosterone in coordinating male life history strategies: The moderating effects of the androgen receptor CAG repeat polymorphism.

    Science.gov (United States)

    Gettler, Lee T; Ryan, Calen P; Eisenberg, Dan T A; Rzhetskaya, Margarita; Hayes, M Geoffrey; Feranil, Alan B; Bechayda, Sonny Agustin; Kuzawa, Christopher W

    2017-01-01

    Partnered fathers often have lower testosterone than single non-parents, which is theorized to relate to elevated testosterone (T) facilitating competitive behaviors and lower T contributing to nurturing. Cultural- and individual-factors moderate the expression of such psychobiological profiles. Less is known about genetic variation's role in individual psychobiological responses to partnering and fathering, particularly as related to T. We examined the exon 1 CAG (polyglutamine) repeat (CAGn) within the androgen receptor (AR) gene. AR CAGn shapes T's effects after it binds to AR by affecting AR transcriptional activity. Thus, this polymorphism is a strong candidate to influence individual-level profiles of "androgenicity." While males with a highly androgenic profile are expected to engage in a more competitive-oriented life history strategy, low androgenic men are at increased risk of depression, which could lead to similar outcomes for certain familial dynamics, such as marriage stability and parenting. Here, in a large longitudinal study of Filipino men (n=683), we found that men who had high androgenicity (elevated T and shorter CAGn) or low androgenicity (lower T and longer CAGn) showed elevated likelihood of relationship instability over the 4.5-year study period and were also more likely be relatively uninvolved with childcare as fathers. We did not find that CAGn moderated men's T responses to the fatherhood transition. In total, our results provide evidence for invested fathering and relationship stability at intermediate levels of androgenicity and help inform our understanding of variation in male reproductive strategies and the individual hormonal and genetic differences that underlie it. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Reversal of androgen inhibition of estrogen-activated sexual behavior by cholinergic agents.

    Science.gov (United States)

    Dohanich, G P; Cada, D A

    1989-12-01

    Androgens have been found to inhibit lordosis activated by estrogen treatment of ovariectomized female rats. In the present experiments, dihydrotestosterone propionate (200 micrograms for 3 days) inhibited the incidence of lordosis in ovariectomized females treated with estradiol benzoate (1 microgram for 3 days). This inhibition of lordosis was reversed 15 min after bilateral intraventricular infusion of physostigmine (10 micrograms/cannula), an acetylcholinesterase inhibitor, or carbachol (0.5 microgram/cannula), a cholinergic receptor agonist. This reversal of inhibition appears to be mediated by cholinergic muscarinic receptors since pretreatment with scopolamine (4 mg/kg, ip), a muscarinic receptor blocker, prevented the reversal of androgen inhibition by physostigmine. These results indicate that androgens may inhibit estrogen-activated lordosis through interference with central cholinergic muscarinic mechanisms.

  2. Neural androgen receptors affect the number of surviving new neurones in the adult dentate gyrus of male mice.

    Science.gov (United States)

    Swift-Gallant, A; Duarte-Guterman, P; Hamson, D K; Ibrahim, M; Monks, D A; Galea, L A M

    2018-04-01

    Adult hippocampal neurogenesis occurs in many mammalian species. In rats, the survival of new neurones within the hippocampus is modulated by the action of androgen via the androgen receptor (AR); however, it is not known whether this holds true in mice. Furthermore, the evidence is mixed regarding whether androgens act in neural tissue or via peripheral non-neural targets to promote new neurone survival in the hippocampus. We evaluated whether the action of androgen via AR underlies the survival of new neurones in mice, and investigated whether increasing AR selectively in neural tissue would increase new neurone survival in the hippocampus. We used the cre-loxP system to overexpress AR only in neural tissues (Nestin-AR). These males were compared with wild-type males, as well as control males with 1 of the 2 mutations required for overexpression. Mice were gonadectomised and injected with the DNA synthesis marker, bromodeoxyuridine (BrdU) and for 37 days (following BrdU injection), mice were treated with oil or dihydrotestosterone (DHT). Using immunohistochemistry, proliferation (Ki67) and survival (BrdU) of new neurones were both evaluated in the dorsal and ventral dentate gyrus. Dihydrotestosterone treatment increased the survival of new neurones in the entire hippocampus in wild-type mice and control mice that only have 1 of 2 necessary mutations for transgenic expression. However, DHT treatment did not increase the survival of new neurones in mice that overexpressed AR in neural tissue. Cell proliferation (Ki67) and cell death (pyknotic cells) were not affected by DHT treatment in wild-type or transgenic males. These results suggest that androgens act via neural AR to affect hippocampal neurogenesis by promoting cell survival; however, the relationship between androgen dose and new neurone survival is nonlinear. © 2018 British Society for Neuroendocrinology.

  3. Targeting Stromal Androgen Receptor Suppresses Prolactin-Driven Benign Prostatic Hyperplasia (BPH)

    Science.gov (United States)

    Lai, Kuo-Pao; Huang, Chiung-Kuei; Fang, Lei-Ya; Izumi, Kouji; Lo, Chi-Wen; Wood, Ronald; Kindblom, Jon; Yeh, Shuyuan

    2013-01-01

    Stromal-epithelial interaction plays a pivotal role to mediate the normal prostate growth, the pathogenesis of benign prostatic hyperplasia (BPH), and prostate cancer development. Until now, the stromal androgen receptor (AR) functions in the BPH development, and the underlying mechanisms remain largely unknown. Here we used a genetic knockout approach to ablate stromal fibromuscular (fibroblasts and smooth muscle cells) AR in a probasin promoter-driven prolactin transgenic mouse model (Pb-PRL tg mice) that could spontaneously develop prostate hyperplasia to partially mimic human BPH development. We found Pb-PRL tg mice lacking stromal fibromuscular AR developed smaller prostates, with more marked changes in the dorsolateral prostate lobes with less proliferation index. Mechanistically, prolactin mediated hyperplastic prostate growth involved epithelial-stromal interaction through epithelial prolactin/prolactin receptor signals to regulate granulocyte macrophage-colony stimulating factor expression to facilitate stromal cell growth via sustaining signal transducer and activator of transcription-3 activity. Importantly, the stromal fibromuscular AR could modulate such epithelial-stromal interacting signals. Targeting stromal fibromuscular AR with the AR degradation enhancer, ASC-J9®, led to the reduction of prostate size, which could be used in future therapy. PMID:23893956

  4. Molecular chaperones enhance the degradation of expanded polyglutamine repeat androgen receptor in a cellular model of spinal and bulbar muscular atrophy

    NARCIS (Netherlands)

    Bailey, CK; Andriola, IFM; Kampinga, HH; Merry, DE

    2002-01-01

    Spinal and bulbar muscular atrophy (SBMA) is one of a growing number of neurodegenerative diseases caused by a polyglutamine-encoding CAG trinucleotide repeat expansion, and is caused by an expansion within exon 1 of the androgen receptor (AR) gene. The family of polyglutamine diseases is

  5. 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

  6. SP600125 Induces Src and Type I IGF Receptor Phosphorylation Independent of JNK

    Directory of Open Access Journals (Sweden)

    Qingbin Kong

    2014-09-01

    Full Text Available c-Jun N-terminal kinases (JNK are members of the mitogen-activated protein kinase (MAPK family that have important roles in signal transduction. The small molecule SP600125 is widely used in biochemical studies as a JNK inhibitor. However, recent studies indicate that SP600125 may also act independent of JNK. Here, we report that SP600125 can induce Src, type I insulin-like growth factor receptor (IGF-IR, Akt and Erk1/2 phosphorylation. Notably, these effects are independent of its inhibition of JNK. Inhibition of Src abrogates the stimulation of IGF-IR, Akt and Erk1/2 phosphorylation. IGF-IR knockdown blunts the induction of both Akt and Erk1/2 phosphorylation by SP600125. Moreover, combination of SP600125 and the Src inhibitor saracatinib synergistically inhibits cell proliferation. We conclude that SP600125 can activate Src-IGF-IR-Akt/Erk1/2 signaling pathways independent of JNK.

  7. Phosphorylation of the Transient Receptor Potential Ankyrin 1 by Cyclin-dependent Kinase 5 affects Chemo-nociception

    OpenAIRE

    Hall, Bradford E.; Prochazkova, Michaela; Sapio, Matthew R.; Minetos, Paul; Kurochkina, Natalya; Binukumar, B. K.; Amin, Niranjana D.; Terse, Anita; Joseph, John; Raithel, Stephen J.; Mannes, Andrew J.; Pant, Harish C.; Chung, Man-Kyo; Iadarola, Michael J.; Kulkarni, Ashok B.

    2018-01-01

    Cyclin-dependent kinase 5 (Cdk5) is a key neuronal kinase that is upregulated during inflammation, and can subsequently modulate sensitivity to nociceptive stimuli. We conducted an in silico screen for Cdk5 phosphorylation sites within proteins whose expression was enriched in nociceptors and identified the chemo-responsive ion channel Transient Receptor Potential Ankyrin 1 (TRPA1) as a possible Cdk5 substrate. Immunoprecipitated full length TRPA1 was shown to be phosphorylated by Cdk5 and th...

  8. Integrated regulation of AMPA glutamate receptor phosphorylation in the striatum by dopamine and acetylcholine.

    Science.gov (United States)

    Xue, Bing; Chen, Elton C; He, Nan; Jin, Dao-Zhong; Mao, Li-Min; Wang, John Q

    2017-01-01

    Dopamine (DA) and acetylcholine (ACh) signals converge onto protein kinase A (PKA) in medium spiny neurons of the striatum to control cellular and synaptic activities of these neurons, although underlying molecular mechanisms are less clear. Here we measured phosphorylation of the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) at a PKA site (S845) as an indicator of AMPAR responses in adult rat brains in vivo to explore how DA and ACh interact to modulate AMPARs. We found that subtype-selective activation of DA D1 receptors (D1Rs), D2 receptors (D2Rs), or muscarinic M4 receptors (M4Rs) induced specific patterns of GluA1 S845 responses in the striatum. These defined patterns support a local multitransmitter interaction model in which D2Rs inhibited an intrinsic inhibitory element mediated by M4Rs to enhance the D1R efficacy in modulating AMPARs. Consistent with this, selective enhancement of M4R activity by a positive allosteric modulator resumed the cholinergic inhibition of D1Rs. In addition, D1R and D2R coactivation recruited GluA1 and PKA preferentially to extrasynaptic sites. In sum, our in vivo data support an existence of a dynamic DA-ACh balance in the striatum which actively modulates GluA1 AMPAR phosphorylation and trafficking. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Cyproterone acetate enhances TRAIL-induced androgen-independent prostate cancer cell apoptosis via up-regulation of death receptor 5.

    Science.gov (United States)

    Chen, Linjie; Wolff, Dennis W; Xie, Yan; Lin, Ming-Fong; Tu, Yaping

    2017-03-07

    Virtually all prostate cancer deaths occur due to obtaining the castration-resistant phenotype after prostate cancer cells escaped from apoptosis and/or growth suppression initially induced by androgen receptor blockade. TNF-related apoptosis-inducing ligand (TRAIL) was an attractive cancer therapeutic agent due to its minimal toxicity to normal cells and remarkable apoptotic activity in tumor cells. However, most localized cancers including prostate cancer are resistant to TRAIL-induced apoptosis, thereby creating a therapeutic challenge of inducing TRAIL sensitivity in cancer cells. Herein the effects of cyproterone acetate, an antiandrogen steroid, on the TRAIL-induced apoptosis of androgen receptor-negative prostate cancer cells are reported. Cell apoptosis was assessed by both annexin V/propidium iodide labeling and poly (ADP-ribose) polymerase cleavage assays. Gene and protein expression changes were determined by quantitative real-time PCR and western blot assays. The effect of cyproterone acetate on gene promoter activity was determined by luciferase reporter assay. Cyproterone acetate but not AR antagonist bicalutamide dramatically increased the susceptibility of androgen receptor-negative human prostate cancer PC-3 and DU145 cells to TRAIL-induced apoptosis but no effects on immortalized human prostate stromal PS30 cells and human embryonic kidney HEK293 cells. Further investigation of the TRAIL-induced apoptosis pathway revealed that cyproterone acetate exerted its effect by selectively increasing death receptor 5 (DR5) mRNA and protein expression. Cyproterone acetate treatment also increased DR5 gene promoter activity, which could be abolished by mutation of a consensus binding domain of transcription factor CCAAT-enhancer-binding protein homologous protein (CHOP) in the DR5 gene promoter. Cyproterone acetate increases CHOP expression in a concentration and time-dependent manner and endoplasmic reticulum stress reducer 4-phenylbutyrate could block

  10. Treadmill Slope Modulates Inflammation, Fiber Type Composition, Androgen, and Glucocorticoid Receptors in the Skeletal Muscle of Overtrained Mice

    Directory of Open Access Journals (Sweden)

    Alisson L. da Rocha

    2017-10-01

    Full Text Available Overtraining (OT may be defined as an imbalance between excessive training and adequate recovery period. Recently, a downhill running-based overtraining (OTR/down protocol induced the nonfunctional overreaching state, which is defined as a performance decrement that may be associated with psychological and hormonal disruptions and promoted intramuscular and systemic inflammation. To discriminate the eccentric contraction effects on interleukin 1beta (IL-1β, IL-6, IL-10, IL-15, and SOCS-3, we compared the release of these cytokines in OTR/down with other two OT protocols with the same external load (i.e., the product between training intensity and volume, but performed in uphill (OTR/up and without inclination (OTR. Also, we evaluated the effects of these OT models on the muscle morphology and fiber type composition, serum levels of fatigue markers and corticosterone, as well as androgen receptor (AR and glucocorticoid receptor (GR expressions. For extensor digitorum longus (EDL, OTR/down and OTR groups increased the cytokines and exhibited micro-injuries with polymorphonuclear infiltration. While OTR/down group increased the cytokines in soleus muscle, OTR/up group only increased IL-6. All OT groups presented micro-injuries with polymorphonuclear infiltration. In serum, while OTR/down and OTR/up protocols increased IL-1β, IL-6, and tumor necrosis factor alpha, OTR group increased IL-1β, IL-6, IL-15, and corticosterone. The type II fibers in EDL and soleus, total and phosphorylated AR levels in soleus, and total GR levels in EDL and soleus were differentially modulated by the OT protocols. In summary, the proinflammatory cytokines were more sensitive for OTR/down than for OTR/up and OTR. Also, the specific treadmill inclination of each OT model influenced most of the other evaluated parameters.

  11. Tissue Selective Androgen Receptor Modulators (SARMs) Increase Pelvic Floor Muscle Mass in Ovariectomized Mice.

    Science.gov (United States)

    Ponnusamy, Suriyan; Sullivan, Ryan D; Thiyagarajan, Thirumagal; Tillmann, Heather; Getzenberg, Robert H; Narayanan, Ramesh

    2017-03-01

    Stress urinary incontinence (SUI), a prevalent condition, is represented by an involuntary leakage of urine that results, at least in part, from weakened or damaged pelvic floor muscles and is triggered by physical stress. Current treatment options are limited with no oral therapies available. The pelvic floor is rich in androgen receptor and molecules with anabolic activity including selective androgen receptor modulators (SARMs) may serve as therapeutic options for individuals with SUI. In this study, two SARMs (GTx-024 and GTx-027) were evaluated in a post-menopausal animal model in order to determine their effect on pelvic floor muscles. Female C57BL/6 mice were ovariectomized and their pelvic muscles allowed to regress. The animals were then treated with vehicle or doses of GTx-024 or GTx-027. Animal total body weight, lean body mass, and pelvic floor muscle weights were measured along with the expression of genes associated with muscle catabolism. Treatment with the SARMs resulted in a restoration of the pelvic muscles to the sham-operated weight. Coordinately, the induction of genes associated with muscle catabolism was inhibited. Although a trend was observed towards an increase in total lean body mass in the SARM-treated groups, no significant differences were detected. Treatment of an ovariectomized mouse model with SARMs resulted in an increase in pelvic floor muscles, which may translate to an improvement of symptoms associated with SUI and serves as the basis for evaluating their clinical use. J. Cell. Biochem. 118: 640-646, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Testosterone treatment increases androgen receptor and aromatase gene expression in myotubes from patients with PCOS and controls, but does not induce insulin resistance

    DEFF Research Database (Denmark)

    Eriksen, Mette Brandt; Glintborg, Dorte; Nielsen, Michael Friberg Bruun

    2014-01-01

    Polycystic ovary syndrome (PCOS) is associated with insulin resistance and increased risk of type 2 diabetes. Skeletal muscle is the major site of insulin mediated glucose disposal and the skeletal muscle tissue is capable to synthesize, convert and degrade androgens. Insulin sensitivity is conse......Polycystic ovary syndrome (PCOS) is associated with insulin resistance and increased risk of type 2 diabetes. Skeletal muscle is the major site of insulin mediated glucose disposal and the skeletal muscle tissue is capable to synthesize, convert and degrade androgens. Insulin sensitivity...... is conserved in cultured myotubes (in vitro) from patients with PCOS, but the effect of testosterone on this insulin sensitivity is unknown. We investigated the effect of 7days testosterone treatment (100nmol/l) on glucose transport and gene expression levels of hormone receptors and enzymes involved...... in the synthesis and conversion of testosterone (HSD17B1, HSD17B2, CYP19A1, SRD5A1-2, AR, ER-α, HSD17B6 and AKR1-3) in myotubes from ten patients with PCOS and ten matched controls. Testosterone treatment significantly increased aromatase and androgen receptor gene expression levels in patients and controls...

  13. Inhibition of glycogen synthase kinase-3β counteracts ligand-independent activity of the androgen receptor in castration resistant prostate cancer.

    Directory of Open Access Journals (Sweden)

    Stefanie V Schütz

    Full Text Available In order to generate genomic signals, the androgen receptor (AR has to be transported into the nucleus upon androgenic stimuli. However, there is evidence from in vitro experiments that in castration-resistant prostate cancer (CRPC cells the AR is able to translocate into the nucleus in a ligand-independent manner. The recent finding that inhibition of the glycogen-synthase-kinase 3β (GSK-3β induces a rapid nuclear export of the AR in androgen-stimulated prostate cancer cells prompted us to analyze the effects of a GSK-3β inhibition in the castration-resistant LNCaP sublines C4-2 and LNCaP-SSR. Both cell lines exhibit high levels of nuclear AR in the absence of androgenic stimuli. Exposure of these cells to the maleimide SB216763, a potent GSK-3β inhibitor, resulted in a rapid nuclear export of the AR even under androgen-deprived conditions. Moreover, the ability of C4-2 and LNCaP-SSR cells to grow in the absence of androgens was diminished after pharmacological inhibition of GSK-3β in vitro. The ability of SB216763 to modulate AR signalling and function in CRPC in vivo was additionally demonstrated in a modified chick chorioallantoic membrane xenograft assay after systemic delivery of SB216763. Our data suggest that inhibition of GSK-3β helps target the AR for export from the nucleus thereby diminishing the effects of mislocated AR in CRPC cells. Therefore, inhibition of GSK-3β could be an interesting new strategy for the treatment of CRPC.

  14. Characterizations of Factors Affecting Androgen Receptor Transcriptional Regulation in Prostate Cancer

    National Research Council Canada - National Science Library

    Garabedian, Michael

    2003-01-01

    .... Expression of ART-27 in LNCaP cells, an androgen-dependent prostate cancer cell line, reduces androgen-mediated cellular proliferation, suggesting that ART-27 plays a role in suppressing cell growth...

  15. Tyrosine phosphorylation of platelet derived growth factor β receptors in coronary artery lesions: implications for vascular remodelling after directional coronary atherectomy and unstable angina pectoris

    Science.gov (United States)

    Abe, J; Deguchi, J; Takuwa, Y; Hara, K; Ikari, Y; Tamura, T; Ohno, M; Kurokawa, K

    1998-01-01

    Background—Growth factors such as platelet derived growth factor (PDGF) have been postulated to be important mediators of neointimal proliferation observed in atherosclerotic plaques and restenotic lesions following coronary interventions. Binding of PDGF to its receptor results in intrinsic receptor tyrosine kinase activation and subsequent cellular migration, proliferation, and vascular contraction.
Aims—To investigate whether the concentration of PDGF β receptor tyrosine phosphorylation obtained from directional coronary atherectomy (DCA) samples correlate with atherosclerotic plaque burden, the ability of diseased vessels to remodel, coronary risk factors, and clinical events.
Methods—DCA samples from 59 patients and 15 non-atherosclerotic left internal thoracic arteries (LITA) were analysed for PDGF β receptor tyrosine phosphorylation content by receptor immunoprecipitation and antiphosphotyrosine western blot. The amount of PDGF β receptor phosphorylation was analysed in relation to angiographic follow up data and clinical variables.
Results—PDGF β receptor tyrosine phosphorylation in the 59 DCA samples was greater than in the 15 non-atherosclerotic LITA (mean (SD) 0.84 (0.67) v 0.17 (0.08) over a control standard, p atherectomy;  restenosis PMID:9616351

  16. Atmospheric Pressure Photoionization Tandem Mass Spectrometry of Androgens in Prostate Cancer

    Science.gov (United States)

    Lih, Fred Bjørn; Titus, Mark A.; Mohler, James L.; Tomer, Kenneth B.

    2010-01-01

    Androgen deprivation therapy is the most common treatment option for advanced prostate cancer. Almost all prostate cancers recur during androgen deprivation therapy, and new evidence suggests that androgen receptor activation persists despite castrate levels of circulating androgens. Quantitation of tissue levels of androgens is critical to understanding the mechanism of recurrence of prostate cancer during androgen deprivation therapy. A liquid chromatography atmospheric pressure photoionization tandem mass spectrometric method was developed for quantitation of tissue levels of androgens. Quantitation of the saturated keto-steroids dihydrotestosterone and 5-α-androstanedione required detection of a novel parent ion, [M + 15]+. The nature of this parent ion was explored and the method applied to prostate tissue and cell culture with comparison to results achieved using electrospray ionization. PMID:20560527

  17. Intratumoral androgen metabolism and actions in invasive lobular carcinoma of the breast.

    Science.gov (United States)

    Yoda, Tomomi; McNamara, Keely May; Miki, Yasuhiro; Takagi, Mayu; Rai, Yoshiaki; Ohi, Yasuyo; Sagara, Yasuaki; Tamaki, Kentaro; Hirakawa, Hisashi; Ishida, Takanori; Suzuki, Takashi; Ohuchi, Noriaki; Sasano, Hironobu

    2014-11-01

    Invasive lobular carcinoma (ILC) accounts for approximately 10% of all breast carcinomas and is characterized by higher levels of androgen receptor (AR) compared to invasive ductal carcinoma (IDC). Despite this potentially androgen-responsive environment, the combined importance of AR and androgen metabolism in non-neoplastic lobules and lobular carcinoma remains unknown. Therefore, in this study, we evaluated the status of pivotal androgen-producing enzymes 17β-hydroxysteroid dehydrogenase type 5 (17βHSD5) and 5α-reductase type 1 (5αRed1) in 178 cases of ILC and surrounding histologically non-neoplastic lobular tissue using immunohistochemistry. Androgen receptor prevalence was higher but androgenic enzymes lower in ILC than non-neoplastic lobules. In ILC cases the status of 5αRed1 and 17βHSD5 was inversely correlated with tumor size (P = 0.0053) and nuclear grade (P = 0.0290), and significantly associated with better overall survival of the patients (P = 0.0059). Based on these findings, we hypothesized that androgen signaling could act as a tumor suppressor. As previous studies suggested that androgens might partially act by increasing levels of the estrogen inactivating enzyme 17β-hydroxysteroid dehydrogenase type 2 (17βHSD2) in IDC tissues, this was reasonably considered a potential mechanism of androgen actions. Significantly positive correlation was detected between the status of androgenic enzymes and 17βHSD2 (P Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  18. Peripheral Androgen Receptor Gene Suppression Rescues Disease in Mouse Models of Spinal and Bulbar Muscular Atrophy

    Directory of Open Access Journals (Sweden)

    Andrew P. Lieberman

    2014-05-01

    Full Text Available Spinal and bulbar muscular atrophy (SBMA is caused by the polyglutamine androgen receptor (polyQ-AR, a protein expressed by both lower motor neurons and skeletal muscle. Although viewed as a motor neuronopathy, data from patients and mouse models suggest that muscle contributes to disease pathogenesis. Here, we tested this hypothesis using AR113Q knockin and human bacterial artificial chromosome/clone (BAC transgenic mice that express the full-length polyQ-AR and display androgen-dependent weakness, muscle atrophy, and early death. We developed antisense oligonucleotides that suppressed AR gene expression in the periphery but not the CNS after subcutaneous administration. Suppression of polyQ-AR in the periphery rescued deficits in muscle weight, fiber size, and grip strength, reversed changes in muscle gene expression, and extended the lifespan of mutant males. We conclude that polyQ-AR expression in the periphery is an important contributor to pathology in SBMA mice and that peripheral administration of therapeutics should be explored for SBMA patients.

  19. Synergistic co-targeting of prostate-specific membrane antigen and androgen receptor in prostate cancer.

    Science.gov (United States)

    Murga, Jose D; Moorji, Sameer M; Han, Amy Q; Magargal, Wells W; DiPippo, Vincent A; Olson, William C

    2015-02-15

    Antibody-drug conjugates (ADCs) are an emerging class of cancer therapies that have demonstrated favorable activity both as single agents and as components of combination regimens. Phase 2 testing of an ADC targeting prostate-specific membrane antigen (PSMA) in advanced prostate cancer has shown antitumor activity. The present study examined PSMA ADC used in combination with potent antiandrogens (enzalutamide and abiraterone) and other compounds. Antiproliferative activity and expression of PSMA, prostate-specific antigen and androgen receptor were evaluated in the prostate cancer cell lines LNCaP and C4-2. Cells were tested for susceptibility to antiandrogens or other inhibitors, used alone and in combination with PSMA ADC. Potential drug synergy or antagonism was evaluated using the Bliss independence method. Enzalutamide and abiraterone demonstrated robust, statistically significant synergy when combined with PSMA ADC. Largely additive activity was observed between the antiandrogens and the individual components of the ADC (free drug and unmodified antibody). Rapamycin also synergized with PSMA ADC in certain settings. Synergy was linked in part to upregulation of PSMA expression. In androgen-dependent LNCaP cells, enzalutamide and abiraterone each inhibited proliferation, upregulated PSMA expression, and synergized with PSMA ADC. In androgen-independent C4-2 cells, enzalutamide and abiraterone showed no measurable antiproliferative activity on their own but increased PSMA expression and synergized with PSMA ADC nonetheless. PSMA expression increased progressively over 3 weeks with enzalutamide and returned to baseline levels 1 week after enzalutamide removal. The findings support exploration of clinical treatment regimens that combine potent antiandrogens and PSMA-targeted therapies for prostate cancer. © 2014 Wiley Periodicals, Inc.

  20. [The impact of the androgen receptor splice variant AR-V7 on the prognosis and treatment of advanced prostate cancer].

    Science.gov (United States)

    Thelen, P; Taubert, H; Duensing, S; Kristiansen, G; Merseburger, A S; Cronauer, M V

    2018-01-25

    A recently discovered mechanism enabling prostate cancer cells to escape the effects of endocrine therapies consists in the synthesis of C-terminally truncated, constitutively active androgen receptor (AR) splice variants (AR-V). Devoid of a functional C-terminal hormone/ligand binding domain, various AR-Vs are insensitive to therapies targeting the androgen/AR signalling axis. Preliminary studies suggest that AR-V7, the most common AR-V, is a promising predictive tumour marker and a relevant selection marker for the treatment of advanced prostate cancer. This review critically outlines recent advances in AR-V7 diagnostics and presents an overview of current AR-V7 targeted therapies. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Establishment of a novel immortalized human prostatic epithelial cell line stably expressing androgen receptor and its application for the functional screening of androgen receptor modulators

    International Nuclear Information System (INIS)

    Yu, Shan; Wang, Ming-Wei; Yao, Xiaoqiang; Chan, F.L.

    2009-01-01

    In this study, we developed a human prostatic epithelial cell line BPH-1-AR stably expressing AR by lentiviral transduction. Characterization by immunoblot and RT-PCR showed that AR was stably expressed in all representative BPH-1-AR clones. Androgen treatment induced a secretory differentiation phenotype in BPH-1-AR cells but suppressed their cell proliferation. Treatments with AR agonists induced transactivation of a transfected PSA-gene promoter reporter in BPH-1-AR cells, whereas this transactivation was suppressed by an AR antagonist flutamide, indicating that the transduced AR in BPH-1-AR cells was functional. Finally, we utilized BPH-1-AR cells to evaluate the androgenic activities and growth effects of five newly developed non-steroidal compounds. Results showed that these compounds showed androgenic activities and growth-inhibitory effects on BPH-1-AR cells. Our results showed that BPH-1-AR cell line would be a valuable in vitro model for the study of androgen-regulated processes in prostatic epithelial cells and identification of compounds with AR-modulating activities.

  2. Androgen receptor agonists increase lean mass, improve cardiopulmonary functions and extend survival in preclinical models of Duchenne muscular dystrophy.

    Science.gov (United States)

    Ponnusamy, Suriyan; Sullivan, Ryan D; You, Dahui; Zafar, Nadeem; He Yang, Chuan; Thiyagarajan, Thirumagal; Johnson, Daniel L; Barrett, Maron L; Koehler, Nikki J; Star, Mayra; Stephenson, Erin J; Bridges, Dave; Cormier, Stephania A; Pfeffer, Lawrence M; Narayanan, Ramesh

    2017-07-01

    Duchenne muscular dystrophy (DMD) is a neuromuscular disease that predominantly affects boys as a result of mutation(s) in the dystrophin gene. DMD is characterized by musculoskeletal and cardiopulmonary complications, resulting in shorter life-span. Boys afflicted by DMD typically exhibit symptoms within 3-5 years of age and declining physical functions before attaining puberty. We hypothesized that rapidly deteriorating health of pre-pubertal boys with DMD could be due to diminished anabolic actions of androgens in muscle, and that intervention with an androgen receptor (AR) agonist will reverse musculoskeletal complications and extend survival. While castration of dystrophin and utrophin double mutant (mdx-dm) mice to mimic pre-pubertal nadir androgen condition resulted in premature death, maintenance of androgen levels extended the survival. Non-steroidal selective-AR modulator, GTx-026, which selectively builds muscle and bone was tested in X-linked muscular dystrophy mice (mdx). GTx-026 significantly increased body weight, lean mass and grip strength by 60-80% over vehicle-treated mdx mice. While vehicle-treated castrated mdx mice exhibited cardiopulmonary impairment and fibrosis of heart and lungs, GTx-026 returned cardiopulmonary function and intensity of fibrosis to healthy control levels. GTx-026 elicits its musculoskeletal effects through pathways that are distinct from dystrophin-regulated pathways, making AR agonists ideal candidates for combination approaches. While castration of mdx-dm mice resulted in weaker muscle and shorter survival, GTx-026 treatment increased the muscle mass, function and survival, indicating that androgens are important for extended survival. These preclinical results support the importance of androgens and the need for intervention with AR agonists to treat DMD-affected boys. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. The Three Dimensional Quantitative Structure Activity Relationships (3D-QSAR and Docking Studies of Curcumin Derivatives as Androgen Receptor Antagonists

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2012-05-01

    Full Text Available Androgen receptor antagonists have been proved to be effective anti-prostate cancer agents. 3D-QSAR and Molecular docking methods were performed on curcumin derivatives as androgen receptor antagonists. The bioactive conformation was explored by docking the potent compound 29 into the binding site of AR. The constructed Comparative Molecular Field Analysis (CoMFA and Comparative Similarity Indices Analysis (CoMSIA models produced statistically significant results with the cross-validated correlation coefficients q2 of 0.658 and 0.567, non-cross-validated correlation coefficients r2 of 0.988 and 0.978, and predicted correction coefficients r2pred of 0.715 and 0.793, respectively. These results ensure the CoMFA and CoMSIA models as a tool to guide the design of novel potent AR antagonists. A set of 30 new analogs were proposed by utilizing the results revealed in the present study, and were predicted with potential activities in the developed models.

  4. Sex differences in androgen receptors of the human mamillary bodies are related to endocrine status rather than to sexual orientation or transsexuality

    NARCIS (Netherlands)

    Kruijver, F. P.; Fernández-Guasti, A.; Fodor, M.; Kraan, E. M.; Swaab, D. F.

    2001-01-01

    In a previous study we found androgen receptor (AR) sex differences in several regions throughout the human hypothalamus. Generally, men had stronger nuclear AR immunoreactivity (AR-ir) than women. The strongest nuclear labeling was found in the caudal hypothalamus in the mamillary body complex

  5. The NLR-related protein NWD1 is associated with prostate cancer and modulates androgen receptor signaling.

    Science.gov (United States)

    Correa, Ricardo G; Krajewska, Maryla; Ware, Carl F; Gerlic, Motti; Reed, John C

    2014-03-30

    Prostate cancer (PCa) is among the leading causes of cancer-related death in men. Androgen receptor (AR) signaling plays a seminal role in prostate development and homeostasis, and dysregulation of this pathway is intimately linked to prostate cancer pathogenesis and progression. Here, we identify the cytosolic NLR-related protein NWD1 as a novel modulator of AR signaling. We determined that expression of NWD1 becomes elevated during prostate cancer progression, based on analysis of primary tumor specimens. Experiments with cultured cells showed that NWD1 expression is up-regulated by the sex-determining region Y (SRY) family proteins. Gene silencing procedures, in conjunction with transcriptional profiling, showed that NWD1 is required for expression of PDEF (prostate-derived Ets factor), which is known to bind and co-regulate AR. Of note, NWD1 modulates AR protein levels. Depleting NWD1 in PCa cell lines reduces AR levels and suppresses activity of androgen-driven reporter genes. NWD1 knockdown potently suppressed growth of androgen-dependent LNCaP prostate cancer cells, thus showing its functional importance in an AR-dependent tumor cell model. Proteomic analysis suggested that NWD1 associates with various molecular chaperones commonly related to AR complexes. Altogether, these data suggest a role for tumor-associated over-expression of NWD1 in dysregulation of AR signaling in PCa.

  6. Molecular insight into the differential anti-androgenic activity of resveratrol and its natural analogs: In Silico approach to understand biological actions

    Science.gov (United States)

    The androgen receptor (AR) is a therapeutic target for the treatment of prostate cancer. Androgen receptor reactivation during the androgen-independent stage of prostate cancer is mediated by numerous mechanisms including expression of AR mutants and splice variants that become non-responsive to con...

  7. Bisphenol-A rapidly enhanced passive avoidance memory and phosphorylation of NMDA receptor subunits in hippocampus of young rats

    International Nuclear Information System (INIS)

    Xu Xiaohong; Li Tao; Luo Qingqing; Hong Xing; Xie Lingdan; Tian Dong

    2011-01-01

    Bisphenol-A (BPA), an endocrine disruptor, is found to influence development of brain and behaviors in rodents. The previous study indicated that perinatal exposure to BPA impaired learning-memory and inhibited N-methyl-D-aspartate receptor (NMDAR) subunits expressions in hippocampus during the postnatal development in rats; and in cultured hippocampal neurons, BPA rapidly promotes dynamic changes in dendritic morphology through estrogen receptor-mediated pathway by concomitant phosphorylation of NMDAR subunit NR2B. In the present study, we examined the rapid effect of BPA on passive avoidance memory and NMDAR in the developing hippocampus of Sprague-Dawley rats at the age of postnatal day 18. The results showed that BPA or estradiol benzoate (EB) rapidly extended the latency to step down from the platform 1 h after footshock and increased the phosphorylation levels of NR1, NR2B, and mitogen-activated extracellular signal-regulated kinase (ERK) in hippocampus within 1 h. While 24 h after BPA or EB treatment, the improved memory and the increased phosphorylation levels of NR1, NR2B, ERK disappeared. Furthermore, pre-treatment with an estrogen receptors (ERs) antagonist, ICI182,780, or an ERK-activating kinase inhibitor, U0126, significantly attenuated EB- or BPA-induced phosphorylations of NR1, NR2B, and ERK within 1 h. These data suggest that BPA rapidly enhanced short-term passive avoidance memory in the developing rats. A non-genomic effect via ERs may mediate the modulation of the phosphorylation of NMDAR subunits NR1 and NR2B through ERK signaling pathway. - Highlights: → BPA rapidly extended the latency to step down from platform 1 h after footshock. → BPA rapidly increased pNR1, pNR2B, and pERK in hippocampus within 1 h. → ERs antagonist or MEK inhibitor attenuated BPA-induced pNR1, pNR2B, and pERK.

  8. 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.

  9. Lapatinib Plasma and Tumor Concentrations and Effects on HER Receptor Phosphorylation in Tumor.

    Directory of Open Access Journals (Sweden)

    Neil L Spector

    Full Text Available The paradigm shift in cancer treatment from cytotoxic drugs to tumor targeted therapies poses new challenges, including optimization of dose and schedule based on a biologically effective dose, rather than the historical maximum tolerated dose. Optimal dosing is currently determined using concentrations of tyrosine kinase inhibitors in plasma as a surrogate for tumor concentrations. To examine this plasma-tumor relationship, we explored the association between lapatinib levels in tumor and plasma in mice and humans, and those effects on phosphorylation of human epidermal growth factor receptors (HER in human tumors.Mice bearing BT474 HER2+ human breast cancer xenografts were dosed once or twice daily (BID with lapatinib. Drug concentrations were measured in blood, tumor, liver, and kidney. In a randomized phase I clinical trial, 28 treatment-naïve female patients with early stage HER2+ breast cancer received lapatinib 1000 or 1500 mg once daily (QD or 500 mg BID before evaluating steady-state lapatinib levels in plasma and tumor.In mice, lapatinib levels were 4-fold higher in tumor than blood with a 4-fold longer half-life. Tumor concentrations exceeded the in vitro IC90 (~ 900 nM or 500 ng/mL for inhibition of HER2 phosphorylation throughout the 12-hour dosing interval. In patients, tumor levels were 6- and 10-fold higher with QD and BID dosing, respectively, compared to plasma trough levels. The relationship between tumor and plasma concentration was complex, indicating multiple determinants. HER receptor phosphorylation varied depending upon lapatinib tumor concentrations, suggestive of changes in the repertoire of HER homo- and heterodimers.Plasma lapatinib concentrations underestimated tumor drug levels, suggesting that optimal dosing should be focused on the site of action to avoid to inappropriate dose escalation. Larger clinical trials are required to determine optimal dose and schedule to achieve tumor concentrations that maximally

  10. Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications.

    Science.gov (United States)

    Lucas-Herald, Angela K; Alves-Lopes, Rheure; Montezano, Augusto C; Ahmed, S Faisal; Touyz, Rhian M

    2017-07-01

    The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca 2+ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function. © 2017 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  11. Linking γ-aminobutyric acid A receptor to epidermal growth factor receptor pathways activation in human prostate cancer.

    Science.gov (United States)

    Wu, Weijuan; Yang, Qing; Fung, Kar-Ming; Humphreys, Mitchell R; Brame, Lacy S; Cao, Amy; Fang, Yu-Ting; Shih, Pin-Tsen; Kropp, Bradley P; Lin, Hsueh-Kung

    2014-03-05

    Neuroendocrine (NE) differentiation has been attributed to the progression of castration-resistant prostate cancer (CRPC). Growth factor pathways including the epidermal growth factor receptor (EGFR) signaling have been implicated in the development of NE features and progression to a castration-resistant phenotype. However, upstream molecules that regulate the growth factor pathway remain largely unknown. Using androgen-insensitive bone metastasis PC-3 cells and androgen-sensitive lymph node metastasis LNCaP cells derived from human prostate cancer (PCa) patients, we demonstrated that γ-aminobutyric acid A receptor (GABA(A)R) ligand (GABA) and agonist (isoguvacine) stimulate cell proliferation, enhance EGF family members expression, and activate EGFR and a downstream signaling molecule, Src, in both PC-3 and LNCaP cells. Inclusion of a GABA(A)R antagonist, picrotoxin, or an EGFR tyrosine kinase inhibitor, Gefitinib (ZD1839 or Iressa), blocked isoguvacine and GABA-stimulated cell growth, trans-phospohorylation of EGFR, and tyrosyl phosphorylation of Src in both PCa cell lines. Spatial distributions of GABAAR α₁ and phosphorylated Src (Tyr416) were studied in human prostate tissues by immunohistochemistry. In contrast to extremely low or absence of GABA(A)R α₁-positive immunoreactivity in normal prostate epithelium, elevated GABA(A)R α₁ immunoreactivity was detected in prostate carcinomatous glands. Similarly, immunoreactivity of phospho-Src (Tyr416) was specifically localized and limited to the nucleoli of all invasive prostate carcinoma cells, but negative in normal tissues. Strong GABAAR α₁ immunoreactivity was spatially adjacent to the neoplastic glands where strong phospho-Src (Tyr416)-positive immunoreactivity was demonstrated, but not in adjacent to normal glands. These results suggest that the GABA signaling is linked to the EGFR pathway and may work through autocrine or paracine mechanism to promote CRPC progression. Copyright © 2013 Elsevier

  12. ANDROGENS REGULATE T47D CELLS MOTILITY AND INVASION THROUGH ACTIN CYTOSKELETON REMODELLING

    Directory of Open Access Journals (Sweden)

    Maria Magdalena Montt-Guevara

    2016-09-01

    Full Text Available The relationship between androgens and breast cancer is controversial. Androgens have complex effects on breast cancer progression and metastasis. Moreover, androgens receptor (AR is expressed in approximately 70% to 90% of invasive breast carcinomas, which has prognostic relevance in basal-like cancers and in triple negative breast cancers. Recent studies have associated the actin-binding proteins of the Ezrin-Radixin-Moesin (ERM family with metastasis in endocrine-sensitive cancers. We studied on T47D breast cancer cells whether androgens with different characteristics, such as testosterone (T, dihydrotestosterone (DHT and dehydroepiandrosterone (DHEA may regulate breast cancer cell motility and invasion through the control of actin remodelling. We demonstrate that androgens promote migration and invasion in T47D via Moesin activation. We show that T and DHEA exert their actions via the AR and estrogen receptor (ER, while the non aromatizable androgen – DHT only recruits AR. We further report that androgen induced significant changes in actin organization with pseudopodia along with membrane ruffles formation, and this process is mediated by Moesin. Our work identifies novel mechanisms of action of androgens on breast cancer cells. Through the modulation of Moesin, androgens alter the architecture of cytoskeleton in T47D breast cancer cell and promote cell migration and invasion. These results could help to understand the biological actions of androgens on breast cancer, and eventually to develop new strategies for treatment of breast cancer.

  13. Tyrosine phosphorylation of Grb14 by Tie2

    Directory of Open Access Journals (Sweden)

    Dumont Daniel J

    2010-10-01

    Full Text Available Abstract Background Growth factor receptor bound (Grb proteins 7, 10 and 14 are a family of structurally related multi-domain adaptor proteins involved in a variety of biological processes. Grb7, 10 and 14 are known to become serine and/or threonine phosphorylated in response to growth factor (GF stimulation. Grb7 and 10 have also been shown to become tyrosine phosphorylated under certain conditions. Under experimental conditions Grb7 is tyrosine phosphorylated by the Tie2/Tie-2/Tek angiogenic receptor tyrosine kinase (RTK. Furthermore, Grb14 has also been shown to interact with Tie2, however tyrosine phosphorylation of this Grb family member has yet to be reported. Results Here we report for the first time tyrosine phosphorylation of Grb14. This phosphorylation requires a kinase competent Tie2 as well as intact tyrosines 1100 and 1106 (Y1100 and Y1106 on the receptor. Furthermore, a complete SH2 domain on Grb14 is required for Grb14 tyrosine phosphorylation by Tie2. Grb14 was also able to become tyrosine phosphorylated in primary endothelial cells when treated with a soluble and potent variant of the Tie2 ligand, cartilage oligomeric matrix protein (COMP Ang1. Conclusion Our results show that Grb14, like its family members Grb7 and Grb10, is able to be tyrosine phosphorylated. Furthermore, our data indicate a role for Grb14 in endothelial signaling downstream of the Tie2 receptor.

  14. Insulin treatment promotes tyrosine phosphorylation of PKR and inhibits polyIC induced PKR threonine phosphorylation.

    Science.gov (United States)

    Swetha, Medchalmi; Ramaiah, Kolluru V A

    2015-11-01

    Tyrosine phosphorylation of insulin receptor beta (IRβ) in insulin treated HepG2 cells is inversely correlated to ser(51) phosphorylation in the alpha-subunit of eukaryotic initiation factor 2 (eIF2α) that regulates protein synthesis. Insulin stimulates interaction between IRβ and PKR, double stranded RNA-dependent protein kinase, also known as EIF2AK2, and phosphorylation of tyrosine residues in PKR, as analyzed by immunoprecipitation and pull down assays using anti-IRβ and anti-phosphotyrosine antibodies, recombinant IRβ and immunopurified PKR. Further polyIC or synthetic double stranded RNA-induced threonine phosphorylation or activation of immunopurified and cellular PKR is suppressed in the presence of insulin treated purified IRβ and cell extracts. Acute, but not chronic, insulin treatment enhances tyrosine phosphorylation of IRβ, its interaction with PKR and tyrosine phosphorylation of PKR. In contrast, lipopolysaccharide that stimulates threonine phosphorylation of PKR and eIF2α phosphorylation and AG 1024, an inhibitor of the tyrosine kinase activity of IRβ, reduces PKR association with the receptor, IRβ in HepG2 cells. These findings therefore may suggest that tyrosine phosphorylated PKR plays a role in the regulation of insulin induced protein synthesis and in maintaining insulin sensitivity, whereas, suppression of polyIC-mediated threonine phosphorylation of PKR by insulin compromises its ability to fight against virus infection in host cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Androgen receptor regulates nuclear trafficking and nuclear domain residency of corepressor HDAC7 in a ligand-dependent fashion

    International Nuclear Information System (INIS)

    Karvonen, Ulla; Jaenne, Olli A.; Palvimo, Jorma J.

    2006-01-01

    In addition to chromosomal proteins, histone deacetylases (HDACs) target transcription factors in transcriptional repression. Here, we show that the class II HDAC family member HDAC7 is an efficient corepressor of the androgen receptor (AR). HDAC7 resided in the cytoplasm in the absence of AR or a cognate ligand, but hormone-occupancy of AR induced nuclear transfer of HDAC7. Nuclear colocalization pattern of AR and HDAC7 was dependent on the nature of the ligand. In the presence of testosterone, a portion of HDAC7 localized to pearl-like nuclear domains, whereas AR occupied with antagonistic ligands cyproterone acetate- or casodex (bicalutamide) recruited HDAC7 from these domains to colocalize with the receptor in speckles and nucleoplasm in a more complete fashion. Ectopic expression of PML-3 relieved the repressive effect of HDAC7 on AR function by sequestering HDAC7 to PML-3 domains. AR acetylation at Lys630/632/633 was not the target of HDAC7 repression, since repression of AR function was independent of these acetylation sites. Moreover, the deacetylase activity of HDAC7 was in part dispensable in the repression of AR function. In sum, our results identify HDAC7 as a novel AR corepressor whose subcellular and subnuclear compartmentalization can be regulated in an androgen-selective manner

  16. 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

  17. Mutation of the SHP-2 binding site in growth hormone (GH) receptor prolongs GH-promoted tyrosyl phosphorylation of GH receptor, JAK2, and STAT5B

    DEFF Research Database (Denmark)

    Stofega, M R; Herrington, J; Billestrup, Nils

    2000-01-01

    phosphorylation. Consistent with the effects on STAT5B phosphorylation, tyrosine-to-phenylalanine mutation of tyrosine 595 prolongs the duration of tyrosyl phosphorylation of GHR and JAK2. These data suggest that tyrosine 595 is a major site of interaction of GHR with SHP-2, and that GHR-bound SHP-2 negatively......Binding of GH to GH receptor (GHR) rapidly and transiently activates multiple signal transduction pathways that contribute to the growth-promoting and metabolic effects of GH. While the events that initiate GH signal transduction, such as activation of the Janus tyrosine kinase JAK2, are beginning...

  18. Androgen receptor CAG repeat polymorphism and epigenetic influence among the south Indian women with Polycystic Ovary Syndrome.

    Directory of Open Access Journals (Sweden)

    Shilpi Dasgupta

    Full Text Available The present study was carried out to assess the role of androgen receptor CAG repeat polymorphism and X chromosome inactivation (XCI pattern among Indian PCOS women and controls which has not been hitherto explored and also to test the hypothesis that shorter CAG alleles would be preferentially activated in PCOS. CAG repeat polymorphism and X chromosome methylation patterns were compared between PCOS and non-PCOS women. 250 PCOS women and 299 controls were included for this study. Androgen receptor CAG repeat sizes, XCI percentages, and clinical and biochemical parameters were measured. The mean CAG repeat number is similar between the cases (18.74±0.13 and controls (18.73±0.12. The obese PCOS women were significantly more frequent in the 20 CAG repeat category than the lean PCOS women, yielding a highly significant odds (p=0.001. Among the women with non-random X-inactivation, alleles with <19 repeats were more frequently activated among cases than controls (p=0.33. CAG repeat polymorphism by itself cannot be considered as a useful marker for discriminating PCOS. We observed a trend of preferential activation of the shorter allele among the PCOS cases with non random XCI pattern. In the obese PCOS women, this microsatellite variation may account for the hyperandrogenicity to a larger extent than the lean PCOS women.

  19. Adult body size and physical activity in relation to risk of breast cancer according to tumor androgen receptor status.

    Science.gov (United States)

    Zhang, Xuehong; Eliassen, A Heather; Tamimi, Rulla M; Hazra, Aditi; Beck, Andrew H; Brown, Myles; Collins, Laura C; Rosner, Bernard; Hankinson, Susan E

    2015-06-01

    Obesity and physical activity have been hypothesized to affect breast cancer risk partly via the androgen signaling pathway. We conducted the first study to evaluate these associations by tumor androgen receptor (AR) status. Height, weight, and physical activity were assessed using questionnaires in the Nurses' Health Study. AR, estrogen receptor (ER), and progesterone receptor (PR) status were determined using immunohistochemistry on tumor tissue and medical/pathology reports. A total of 1,701 AR(+) and 497 AR(-) cases were documented during 26 years of follow-up of 103,577 women. After adjusting for ER/PR status and other risk factors, the relative risks (RR) and 95% confidence intervals (95% CI) for every 5 kg/m(2) increase in body mass index (BMI) were 1.07 (1.01-1.13) for AR(+) and 1.16 (1.05-1.29) for AR(-) tumors (P-heterogeneity = 0.17). The RRs (95% CIs) per 5 hours of brisk walking/week were 0.87 (0.73-1.04) for AR(+) and 0.67 (0.45-0.99) for AR(-) tumors (P-heterogeneity = 0.22). Further, BMI, but not physical activity, associations differed significantly across ER/PR/AR subtypes (P-heterogeneity = 0.04 and 0.63, respectively). The RRs (95% CIs) for 5 kg/m(2) increase in BMI were 1.23 (1.04-1.45) for ER(+)PR(+)AR(-), 1.19 (1.01-1.39) for ER(-)PR(-)AR(-), 1.15 (1.08-1.23) for ER(+)PR(+)AR(+), and 0.88 (0.75-1.03) for ER(+)PR(-)AR(+) tumors. Higher BMI was associated with an increased risk of both AR(+) and AR(-) breast tumors in postmenopausal women, whereas physical activity, including brisk walking, was associated with a reduced risk of both subtypes. In addition, a significant positive association was observed between higher BMI and ER(-)PR(-)AR(-) tumors. The similar associations observed by AR status suggest that mechanisms other than androgen signaling underlie these two breast cancer risk factors. ©2015 American Association for Cancer Research.

  20. Influence of Androgen Receptor in Vascular Cells on Reperfusion following Hindlimb Ischaemia.

    Directory of Open Access Journals (Sweden)

    Junxi Wu

    Full Text Available Studies in global androgen receptor knockout (G-ARKO and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall.Mice with selective deletion of AR (ARKO from vascular smooth muscle cells (SM-ARKO, endothelial cells (VE-ARKO, or both (SM/VE-ARKO were compared with wild type (WT controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10-10-10-7M; 6 days.These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis.

  1. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    BACKGROUND: Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. RESULTS: Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. CONCLUSION: Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  2. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-08-22

    Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  3. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Hatt Hanns

    2011-08-01

    Full Text Available Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  4. Androgen receptor regulated microRNA miR-182-5p promotes prostate cancer progression by targeting the ARRDC3/ITGB4 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jingjing [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Xu, Chen [Research Center of Developmental Biology, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Department of Orthopedics, Changzheng Hospital Affiliated to Second Military Medical University, 415th Feng Yang Road, Shanghai, 200003 (China); Fang, Ziyu; Li, Yaoming [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Liu, Houqi; Wang, Yue [Research Center of Developmental Biology, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Translational Medicine Center, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Xu, Chuanliang [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Sun, Yinghao, E-mail: sunyh@medmail.com.cn [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China)

    2016-05-20

    Abstracts: MicroRNAs (miRNAs) are important endogenous gene regulators that play key roles in prostate cancer development and metastasis. However, specific miRNA expression patterns in prostate cancer tissues from Chinese patients remain largely unknown. In this study, we compared miRNA expression patterns in 65 pairs of prostate cancer and para-cancer tissues by RNA sequencing and found that miR-182-5p was the most up-regulated miRNA in prostate cancer tissues. The result was validated using realtime PCR in 18 pairs of prostate cancer and para-cancer tissues. In in vitro analysis, it was confirmed that miR-182-5p promotes prostate cancer cell proliferation, invasion and migration and inhibit apoptosis. In addition, the androgen receptor directly regulated the transcription of miR-182-5p, which could target to the 3′UTR of ARRDC3 mRNA and affect the expression of ARRDC3 and its downstream gene ITGB4. For the in vivo experiment, miR-182-5p overexpression also promoted the growth and progression of prostate cancer tumors. In this regard, we suggest that miR-182-5p may be a key androgen receptor-regulated factor that contributes to the development and metastasis of Chinese prostate cancers and may be a potential target for the early diagnosis and therapeutic studies of prostate cancer. -- Highlights: •miR-182-5p is the mostly up-regulated miRNA in Chinese prostate cancer. •miR-182-5p is regulated by androgen receptor. •miR-182-5p promotes prostate cancer progression. •miR-182-5p regulates ARRDC3/ITGB4 pathway.

  5. Overexpression of HepaCAM inhibits cell viability and motility through suppressing nucleus translocation of androgen receptor and ERK signaling in prostate cancer.

    Science.gov (United States)

    Song, Xuedong; Wang, Yin; Du, Hongfei; Fan, Yanru; Yang, Xue; Wang, Xiaorong; Wu, Xiaohou; Luo, Chunli

    2014-07-01

    HepaCAM is suppressed in a variety of human cancers, and involved in cell adhesion, growth, migration, invasion, and survival. However, the expression and function of HepaCAM in prostate cancer are still unknown. HepaCAM expression has been detected by RT-PCR, Western blotting and immunohistochemistry staining in prostate cell lines RWPE-1, LNCap, DU145, PC3, and in 75 human prostate tissue specimens, respectively. Meanwhile, the cell proliferation ability was detected by WST-8 assay. The role of HepaCAM in prostate cancer cell migration and invasion was examined by wound healing and transwell assay. And flow cytometry was used to observe the apoptosis of prostate cancer cells. Then we detected changes of Androgen Receptor translocation and ERK signaling using immunofluorescence staining and western blot after overexpression of HepaCAM. The HepaCAM expression was significantly down-regulated in prostate cancer tissues and undetected in prostate cancer cells. However, the low HepaCAM expression was not statistically associated with clinicopathological characteristics of prostate cancer. Overexpression of HepaCAM in prostate cancer cells decreased the cell proliferation, migration and invasion, and induced the cell apoptosis. Meanwhile, HepaCAM prevented the androgen receptor translocation from the cytoplasm to the nucleus and down-regulated the MAPK/ERK signaling. Our results suggested that HepaCAM acted as a tumor suppressor in prostate cancer. HepaCAM inhibited cell viability and motility which might be through suppressing the nuclear translocation of Androgen Receptor and down-regulating the ERK signaling. Therefore, it was indicated that HepaCAM may be a potential therapeutic target for prostate cancer. © 2014 Wiley Periodicals, Inc.

  6. Androgen receptor regulated microRNA miR-182-5p promotes prostate cancer progression by targeting the ARRDC3/ITGB4 pathway

    International Nuclear Information System (INIS)

    Yao, Jingjing; Xu, Chen; Fang, Ziyu; Li, Yaoming; Liu, Houqi; Wang, Yue; Xu, Chuanliang; Sun, Yinghao

    2016-01-01

    Abstracts: MicroRNAs (miRNAs) are important endogenous gene regulators that play key roles in prostate cancer development and metastasis. However, specific miRNA expression patterns in prostate cancer tissues from Chinese patients remain largely unknown. In this study, we compared miRNA expression patterns in 65 pairs of prostate cancer and para-cancer tissues by RNA sequencing and found that miR-182-5p was the most up-regulated miRNA in prostate cancer tissues. The result was validated using realtime PCR in 18 pairs of prostate cancer and para-cancer tissues. In in vitro analysis, it was confirmed that miR-182-5p promotes prostate cancer cell proliferation, invasion and migration and inhibit apoptosis. In addition, the androgen receptor directly regulated the transcription of miR-182-5p, which could target to the 3′UTR of ARRDC3 mRNA and affect the expression of ARRDC3 and its downstream gene ITGB4. For the in vivo experiment, miR-182-5p overexpression also promoted the growth and progression of prostate cancer tumors. In this regard, we suggest that miR-182-5p may be a key androgen receptor-regulated factor that contributes to the development and metastasis of Chinese prostate cancers and may be a potential target for the early diagnosis and therapeutic studies of prostate cancer. -- Highlights: •miR-182-5p is the mostly up-regulated miRNA in Chinese prostate cancer. •miR-182-5p is regulated by androgen receptor. •miR-182-5p promotes prostate cancer progression. •miR-182-5p regulates ARRDC3/ITGB4 pathway.

  7. Glycoprotein VI/Fc receptor γ chain-independent tyrosine phosphorylation and activation of murine platelets by collagen

    OpenAIRE

    Jarvis, Gavin E.; Best, Denise; Watson, Steve P.

    2004-01-01

    We have investigated the ability of collagen to induce signalling and functional responses in suspensions of murine platelets deficient in the FcRγ (Fc receptor γ) chain, which lack the collagen receptor GPVI (glycoprotein VI). In the absence of the FcRγ chain, collagen induced a unique pattern of tyrosine phosphorylation which was potentiated by the thromboxane analogue U46619. Immunoprecipitation studies indicated that neither collagen alone nor the combination of collagen plus U46619 induc...

  8. Interrelation of androgen receptor and miR-30a and miR-30a function in ER-, PR-, AR+ MDA-MB-453 breast cancer cells.

    Science.gov (United States)

    Lyu, Shuhua; Liu, Han; Liu, Xia; Liu, Shan; Wang, Yahong; Yu, Qi; Niu, Yun

    2017-10-01

    The association between androgen-induced androgen receptor (AR) activating signal and microRNA (miR)-30a was investigated, as well as the function of miR-30a in estrogen receptor-negative (ER - ), progesterone receptor-negative (PR - ), and AR-positive (AR + ) MDA-MB-453 breast cancer cells. Androgen-induced AR activating signal upregulated the expression of AR, and downregulated the expression of miR-30a, b and c. Bioinformatics analysis indicated a putative miR-30a, b and c binding site in the 3'-untranslated region of AR mRNA. It was confirmed that the AR gene is a direct target of miR-30a, whereas AR does not target the miR-30a promoter, and AR activating signal may indirectly downregulate miR-30a through other cell signaling pathways. In this positive feedback mechanism AR is then upregulated through miR-30a. Overexpression of miR-30a inhibited cell proliferation, whereas inhibition of miR-30a expression by specific antisense oligonucleotides, increased cell growth. Previously, androgen-induced AR activating signal was demonstrated to inhibit cell proliferation in ER - , PR - and AR + MDA-MB-453 breast cancer cells, but AR activating signal downregulated the expression of miR-30a, relieving the inhibition of MDA-MB-453 cell growth. Therefore, in MDA-MB-453 breast cancer cells, miR-30a has two different functions regarding cell growth: Inhibition of cell proliferation through a positive feedback signaling pathway; and the relative promotion of cell proliferation through downregulation of miR-30a. Thus, the association between AR activating signal and microRNAs is complex, and microRNAs may possess different functions due to different signaling pathways. Although the results of the present study were obtained in one cell line, they contribute to subsequent studies on ER - , PR - and AR + breast cancer.

  9. Androgen receptor-dependent and -independent mechanisms driving prostate cancer progression: Opportunities for therapeutic targeting from multiple angles

    Science.gov (United States)

    Hoang, David T; Iczkowski, Kenneth A; Kilari, Deepak; See, William; Nevalainen, Marja T

    2017-01-01

    Despite aggressive treatment for localized cancer, prostate cancer (PC) remains a leading cause of cancer-related death for American men due to a subset of patients progressing to lethal and incurable metastatic castrate-resistant prostate cancer (CRPC). Organ-confined PC is treated by surgery or radiation with or without androgen deprivation therapy (ADT), while options for locally advanced and disseminated PC include radiation combined with ADT, or systemic treatments including chemotherapy. Progression to CRPC results from failure of ADT, which targets the androgen receptor (AR) signaling axis and inhibits AR-driven proliferation and survival pathways. The exact mechanisms underlying the transition from androgen-dependent PC to CRPC remain incompletely understood. Reactivation of AR has been shown to occur in CRPC despite depletion of circulating androgens by ADT. At the same time, the presence of AR-negative cell populations in CRPC has also been identified. While AR signaling has been proposed as the primary driver of CRPC, AR-independent signaling pathways may represent additional mechanisms underlying CRPC progression. Identification of new therapeutic strategies to target both AR-positive and AR-negative PC cell populations and, thereby, AR-driven as well as non-AR-driven PC cell growth and survival mechanisms would provide a two-pronged approach to eliminate CRPC cells with potential for synthetic lethality. In this review, we provide an overview of AR-dependent and AR-independent molecular mechanisms which drive CRPC, with special emphasis on the role of the Jak2-Stat5a/b signaling pathway in promoting castrate-resistant growth of PC through both AR-dependent and AR-independent mechanisms. PMID:27741508

  10. Chiral dimethylamine flutamide derivatives-modeling, synthesis, androgen receptor affinities and carbon-11 labeling

    International Nuclear Information System (INIS)

    Jacobson, Orit; Laky, Desideriu; Carlson, Kathryn E.; Elgavish, Sharona; Gozin, Michael; Even-Sapir, Einat; Leibovitc, Ilan; Gutman, Mordechai; Chisin, Roland; Katzenellenbogen, John A.; Mishani, Eyal

    2006-01-01

    Most prostate cancers are androgen dependent upon initial diagnosis. On the other hand, some very aggressive forms of prostate cancer were shown to have lost the expression of the androgen receptor (AR). Although the AR is routinely targeted in endocrine treatment, the clinical outcome remains suboptimal. Therefore, it is crucial to demonstrate the presence and activity of the AR in each case of prostate cancer, before and after treatment. While noninvasive positron emission tomography (PET) has the potential to determine AR expression of tumor cells in vivo, fully optimized PET imaging agents are not yet available. Based on molecular modeling, three novel derivatives of hydroxyflutamide (Compounds 1-3) were designed and synthesized. They contain an electron-rich group (dimethylamine) located on the methyl moiety, which may confer a better stability to the molecule in vivo. Compounds 1-3 have AR binding that is similar or higher than that of the currently used commercial drugs. An automated carbon-11 radiolabeling route was developed, and the compounds were successfully labeled with a 10-15% decay-corrected radiochemical yield, 99% radiochemical purity and a specific activity of 4Ci/μmol end of bombardment (n=15). These labeled biomarkers may facilitate the future quantitative molecular imaging of AR-positive prostate cancer using PET and may also allow for image-guided treatment of prostate cancer

  11. Androgen Receptor-Mediated Growth Suppression of HPr-1AR and PC3-Lenti-AR Prostate Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Young-Chae Kim

    Full Text Available The androgen receptor (AR mediates the developmental, physiologic, and pathologic effects of androgens including 5α-dihydrotestosterone (DHT. However, the mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells are not well understood, though they are central to prostate development, homeostasis, and neoplasia. Here, we identify androgen-responsive genes that restrain cell cycle progression and proliferation of human prostate epithelial cell lines (HPr-1AR and PC3-Lenti-AR, and we investigate the mechanisms through which AR regulates their expression. DHT inhibited proliferation of HPr-1AR and PC3-Lenti-AR, and cell cycle analysis revealed a prolonged G1 interval. In the cell cycle, the G1/S-phase transition is initiated by the activity of cyclin D and cyclin-dependent kinase (CDK complexes, which relieve growth suppression. In HPr-1AR, cyclin D1/2 and CDK4/6 mRNAs were androgen-repressed, whereas CDK inhibitor, CDKN1A, mRNA was androgen-induced. The regulation of these transcripts was AR-dependent, and involved multiple mechanisms. Similar AR-mediated down-regulation of CDK4/6 mRNAs and up-regulation of CDKN1A mRNA occurred in PC3-Lenti-AR. Further, CDK4/6 overexpression suppressed DHT-inhibited cell cycle progression and proliferation of HPr-1AR and PC3-Lenti-AR, whereas CDKN1A overexpression induced cell cycle arrest. We therefore propose that AR-mediated growth suppression of HPr-1AR involves cyclin D1 mRNA decay, transcriptional repression of cyclin D2 and CDK4/6, and transcriptional activation of CDKN1A, which serve to decrease CDK4/6 activity. AR-mediated inhibition of PC3-Lenti-AR proliferation occurs through a similar mechanism, albeit without down-regulation of cyclin D. Our findings provide insight into AR-mediated regulation of prostate epithelial cell proliferation.

  12. Testosterone increases renal anti-aging klotho gene expression via the androgen receptor-mediated pathway.

    Science.gov (United States)

    Hsu, Shih-Che; Huang, Shih-Ming; Lin, Shih-Hua; Ka, Shuk-Man; Chen, Ann; Shih, Meng-Fu; Hsu, Yu-Juei

    2014-12-01

    Gender is known to be associated with longevity and oestrogen administration induced longevity-associated gene expression is one of the potential mechanisms underlying the benefits of oestrogen on lifespan, whereas the role of testosterone in the regulation of longevity-associated gene expressions remains largely unclear. The klotho gene, predominantly expressed in the kidney, has recently been discovered to be an aging suppressor gene. In the present study, we investigated the regulatory effects of testosterone on renal klotho gene expression in vivo and in vitro. In testosterone-administered mouse kidney and NRK-52E cells, increased klotho expression was accompanied by the up-regulation of the nuclear androgen receptor (AR). Overexpression of AR enhanced the expression of klotho mRNA and protein. Conversely, testosterone-induced klotho expression was attenuated in the presence of flutamide, an AR antagonist. A reporter assay and a chromatin immunoprecipitation (ChIP) assay demonstrated that AR directly binds to the klotho promoter via androgen response elements (AREs) which reconfirmed its importance for AR binding via the element mutation. In summary, our study demonstrates that testosterone up-regulates anti-aging klotho together with AR expression in the kidney in vivo and in vitro by recruiting AR on to the AREs of the klotho promoter.

  13. Downregulation of androgen receptors by NaAsO2 via inhibition of AKT-NF-κB and HSP90 in castration resistant prostate cancer.

    Science.gov (United States)

    Kim, Yunlim; Park, Sang Eun; Moon, Jeong-Weon; Kim, Bong-Min; Kim, Ha-Gyeong; Jeong, In Gab; Yoo, Sangjun; Ahn, Jae Beom; You, Dalsan; Pak, Jhang Ho; Kim, Sujong; Hwang, Jung Jin; Kim, Choung-Soo

    2017-07-01

    Androgen and androgen receptor (AR) play essential roles in the development and maintenance of prostate cancer. The recently identified AR splice variants (AR-Vs) have been considered as a plausible mechanism for the primary resistance against androgen deprivation therapy (ADT) in castration-resistant prostate cancer (CRPC). Sodium meta-arsenite (NaAsO 2 ; KML001; Kominox), a trivalent arsenical, is an orally bioavailable and water soluble, which is currently in phase I/II clinical trials for the treatment of prostate cancer. It has a potent anti-cancer effect on prostate cancer cells and xenografts. The aim of this study was to examine the effect of NaAsO 2 on AR signaling in LNCaP and 22Rv1 CRPC cells. We used hormone-sensitive LNCaP cells, hormone-insensitive 22Rv1 cells, and CRPC patient-derived primary cells. We analyzed anti-cancer effect of NaAsO 2 using real-time quantitative reverse transcription-PCR, Western blotting, immunofluorescence staining and CellTiter Glo® luminescent assay. Statistical evaluation of the results was performed by one-way ANOVA. NaAsO 2 significantly reduced the translocation of AR and AR-Vs to the nucleus as well as their level in LNCaP and 22Rv1 cells. Besides, the level of the prostate-specific antigen (PSA), downstream target gene of AR, was also decreased. This compound was also an effective modulator of AKT-dependent NF-κB activation which regulates AR. NaAsO 2 significantly inhibited phosphorylation of AKT and expression and nuclear translocation of NF-κB. We then investigated the effect of NaAsO 2 on AR stabilization. NaAsO 2 promoted HSP90 acetylation by down-regulating HDAC6, which reduces the stability of AR in prostate cancer cells. Here, we show that NaAsO 2 disrupts AR signaling at multiple levels by affecting AR expression, stability, and degradation in primary tumor cell cultures from prostate cancer patients as well as CRPC cell lines. These results suggest that NaAsO 2 could be a novel therapeutics for prostate

  14. Development of Novel Drugs That Target Coactivation Sites of the Androgen Receptor for Treatment of Antiandrogen-Resistant Prostate Cancer

    Science.gov (United States)

    2015-12-01

    quantifying their effect on the production of the prostate specific antigen (PSA) in prostate cancer cell lines (11). PSA is AR-regulated serine protease and... products . The hydroxylation products were observed in lesser amounts. The IV and IP serum profiles of VPC-13566 suggest that it could be administered IP...Glucocorticoid, mineralocorticoid, progesterone , and androgen receptors. Pharmacological Reviews. 2006;58:782-97. 2. Denmeade SR, Isaacs JT. A

  15. The function of androgen/androgen receptor and insulin growth factor‑1/insulin growth factor‑1 receptor on the effects of Tribulus terrestris extracts in rats undergoing high intensity exercise.

    Science.gov (United States)

    Wu, Yin; Yang, Hongfang; Wang, Xiaohui

    2017-09-01

    Our previous study demonstrated that treatment with Tribulus terrestris (TT) extracts (120 mg/kg) promoted the muscle weight gain and performance of rats undergoing high intensity exercise. The present study was designed to explore the mechanisms underlying the effect of treatment with TT extracts and the involvement of androgens, the androgen receptor (AR), insulin growth factor‑1 (IGF‑1) and the IGF‑1 receptor (IGF‑1R). A total of 32 Sprague‑Dawley rats were randomly divided into groups as follows: Control; TT, treated with TT extracts, E, high intensity exercise; E+TT, high intensity exercise plus TT treatment. The rats of the E and E+TT groups underwent high intensity exercise with a progressively increasing load for 5 weeks, and TT extracts were intragastrically administered in the TT and E+TT rats 30 min prior to training. TT extract composition was analyzed using ultra‑high performance liquid chromatography‑quadrupole‑time of flight mass spectrometry. Testosterone and IGF‑1 plasma levels and AR, IGF‑1R and myosin heavy chain (MHC) protein levels in muscles were determined by ELISA and western blotting, respectively. The saponins tigogenin and diosgenin comprised ~71.35% of the total peak area. Compared with the E group, TT extracts increased the testosterone and IGF‑1 plasma levels, and AR, IGF‑1R and MHC protein levels in the gastrocnemius of rats undergoing high intensity exercise, accompanied with increased body weight and gastrocnemius weight. In conclusion, the effect of TT extracts on the performance of high intensity exercise rats may be attributed to increased levels of circulating testosterone and IGF‑1 and increased AR and IGF‑1R protein expression levels in the gastrocnemius, resulting in increased muscle weight and increased MHC in the gastrocnemius. The present study provided preliminary evidence supporting the use of TT extracts as a dietary supplement for the promotion of skeletal muscle mass increase and the

  16. 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.

  17. Analysis of the molecular networks in androgen dependent and independent prostate cancer revealed fragile and robust subsystems.

    Directory of Open Access Journals (Sweden)

    Ryan Tasseff

    Full Text Available Androgen ablation therapy is currently the primary treatment for metastatic prostate cancer. Unfortunately, in nearly all cases, androgen ablation fails to permanently arrest cancer progression. As androgens like testosterone are withdrawn, prostate cancer cells lose their androgen sensitivity and begin to proliferate without hormone growth factors. In this study, we constructed and analyzed a mathematical model of the integration between hormone growth factor signaling, androgen receptor activation, and the expression of cyclin D and Prostate-Specific Antigen in human LNCaP prostate adenocarcinoma cells. The objective of the study was to investigate which signaling systems were important in the loss of androgen dependence. The model was formulated as a set of ordinary differential equations which described 212 species and 384 interactions, including both the mRNA and protein levels for key species. An ensemble approach was chosen to constrain model parameters and to estimate the impact of parametric uncertainty on model predictions. Model parameters were identified using 14 steady-state and dynamic LNCaP data sets taken from literature sources. Alterations in the rate of Prostatic Acid Phosphatase expression was sufficient to capture varying levels of androgen dependence. Analysis of the model provided insight into the importance of network components as a function of androgen dependence. The importance of androgen receptor availability and the MAPK/Akt signaling axes was independent of androgen status. Interestingly, androgen receptor availability was important even in androgen-independent LNCaP cells. Translation became progressively more important in androgen-independent LNCaP cells. Further analysis suggested a positive synergy between the MAPK and Akt signaling axes and the translation of key proliferative markers like cyclin D in androgen-independent cells. Taken together, the results support the targeting of both the Akt and MAPK

  18. A selective androgen receptor modulator with minimal prostate hypertrophic activity enhances lean body mass in male rats and stimulates sexual behavior in female rats.

    Science.gov (United States)

    Allan, George F; Tannenbaum, Pamela; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Zhang, Xuqing; Sui, Zhihua; Lundeen, Scott G

    2007-08-01

    Androgen receptor (AR) ligands with tissue selectivity (selective androgen receptor modulators, or SARMs) have potential for treating muscle wasting, hypogonadism of aging, osteoporosis, female sexual dysfunction, and other indications. JNJ-28330835 is a nonsteroidal AR ligand with mixed agonist and antagonist activity in androgen-responsive cell-based assays. It is an orally active SARM with muscle selectivity in orchidectomized rat models. It stimulated growth of the levator ani muscle, stimulating maximal growth at a dose of 10 mg/kg. At the same time, JNJ-28330835 reduced prostate weight in intact rats by a mean of 30% at 10 mg/kg, while having no inhibitory effect on muscle. Using magnetic resonance imaging (MRI) to monitor body composition, it prevented half of the loss of lean body mass associated with orchidectomy, and restored about 30% of lost lean mass to aged orchidectomized rats. It had agonist effects on markers of both osteoclast and osteoblast activity, suggesting that it reduces bone turnover. In a model of sexual behavior, JNJ-28330835 enhanced the preference of ovariectomized female rats for sexually intact male rats over nonsexual orchidectomized males. JNJ-28330835 is a prostate-sparing SARM with the potential for clinically beneficial effects in muscle-wasting diseases and sexual function disorders.

  19. Differential effects of androgens on coronary blood flow regulation and arteriolar diameter in intact and castrated swine

    Directory of Open Access Journals (Sweden)

    O’Connor Erin K

    2012-05-01

    Full Text Available Abstract Background Low endogenous testosterone levels have been shown to be a risk factor for the development of cardiovascular disease and cardiovascular benefits associated with testosterone replacement therapy are being advocated; however, the effects of endogenous testosterone levels on acute coronary vasomotor responses to androgen administration are not clear. The objective of this study was to compare the effects of acute androgen administration on in vivo coronary conductance and in vitro coronary microvascular diameter in intact and castrated male swine. Methods Pigs received intracoronary infusions of physiologic levels (1–100 nM of testosterone, the metabolite 5α-dihydrotestosterone, and the epimer epitestosterone while left anterior descending coronary blood flow and mean arterial pressure were continuously monitored. Following sacrifice, coronary arterioles were isolated, cannulated, and exposed to physiologic concentrations (1–100 nM of testosterone, 5α-dihydrotestosterone, and epitestosterone. To evaluate effects of the androgen receptor on acute androgen dilation responses, real-time PCR and immunohistochemistry for androgen receptor were performed on conduit and resistance coronary vessels. Results In vivo, testosterone and 5α-dihydrotestosterone produced greater increases in coronary conductance in the intact compared to the castrated males. In vitro, percent maximal dilation of microvessels was similar between intact and castrated males for testosterone and 5α-dihydrotestosterone. In both studies epitestosterone produced significant increases in conductance and microvessel diameter from baseline in the intact males. Androgen receptor mRNA expression and immunohistochemical staining were similar in intact and castrated males. Conclusions Acute coronary vascular responses to exogenous androgen administration are increased by endogenous testosterone, an effect unrelated to changes in androgen receptor expression.

  20. Androgen Receptor Gene Polymorphism, Aggression, and Reproduction in Tanzanian Foragers and Pastoralists

    Science.gov (United States)

    Butovskaya, Marina L.; Lazebny, Oleg E.; Vasilyev, Vasiliy A.; Dronova, Daria A.; Karelin, Dmitri V.; Mabulla, Audax Z. P.; Shibalev, Dmitri V.; Shackelford, Todd K.; Fink, Bernhard; Ryskov, Alexey P.

    2015-01-01

    The androgen receptor (AR) gene polymorphism in humans is linked to aggression and may also be linked to reproduction. Here we report associations between AR gene polymorphism and aggression and reproduction in two small-scale societies in northern Tanzania (Africa)—the Hadza (monogamous foragers) and the Datoga (polygynous pastoralists). We secured self-reports of aggression and assessed genetic polymorphism of the number of CAG repeats for the AR gene for 210 Hadza men and 229 Datoga men (aged 17–70 years). We conducted structural equation modeling to identify links between AR gene polymorphism, aggression, and number of children born, and included age and ethnicity as covariates. Fewer AR CAG repeats predicted greater aggression, and Datoga men reported more aggression than did Hadza men. In addition, aggression mediated the identified negative relationship between CAG repeats and number of children born. PMID:26291982

  1. Minnelide Inhibits Androgen Dependent, Castration Resistant Prostate Cancer Growth by Decreasing Expression of Androgen Receptor Full Length and Splice Variants.

    Science.gov (United States)

    Isharwal, Sumit; Modi, Shrey; Arora, Nivedita; Uhlrich, Charles; Giri, Bhuwan; Barlass, Usman; Soubra, Ayman; Chugh, Rohit; Dehm, Scott M; Dudeja, Vikas; Saluja, Ashok; Banerjee, Sulagna; Konety, Badrinath

    2017-05-01

    With almost 30,000 deaths per year, prostate cancer is the second-leading cause of cancer-related death in men. Androgen Deprivation Therapy (ADT) has been the corner stone of prostate cancer treatment for decades. However, despite an initial response of prostate cancer to ADT, this eventually fails and the tumors recur, resulting in Castration Resistant Prostate Cancer (CRPC). Triptolide, a diterpene triepoxide, has been tested for its anti-tumor properties in a number of cancers for over a decade. Owing to its poor solubility in aqueous medium, its clinical application had been limited. To circumvent this problem, we have synthesized a water-soluble pro-drug of triptolide, Minnelide, that is currently being evaluated in a Phase 1 clinical trial against gastrointestinal tumors. In the current study, we assessed the therapeutic potential of Minnelide and its active compound triptolide against androgen dependent prostate cancer both in vitro as well as in vivo. Cell viability was measured by a MTT based assay after treating prostate cancer cells with multiple doses of triptolide. Apoptotic cell death was measured using a caspase 3/7 activity. Androgen Receptor (AR) promoter-binding activity was evaluated by using luciferase reporter assay. For evaluating the effect in vivo, 22Rv1 cells were implanted subcutaneously in animals, following which, treatment was started with 0.21 mg/kg Minnelide. Our study showed that treatment with triptolide induced apoptotic cell death in CRPC cells. Triptolide treatment inhibited AR transcriptional activity and decreased the expression of AR and its splice variants both at the mRNA and the protein level. Our studies show that triptolide inhibits nuclear translocation of Sp1, resulting in its decreased transcriptional activity leading to downregulation of AR and its splice variants in prostate cancer cells. In vivo, Minnelide (0.21 mg/kg) regressed subcutaneous tumors derived from CRPC 22RV1 at our study endpoint. Our animal

  2. PROLACTIN-INDUCED TYROSINE PHOSPHORYLATION, ACTIVATION AND RECEPTOR ASSOCIATION OF FOCAL ADHESION KINASE (FAK) IN MAMMARY EPITHELIAL CELLS

    Science.gov (United States)

    Prolactin-Induced Tyrosine Phosphorylation, Activation and ReceptorAssociation of Focal Adhesion Kinase (FAK) in Mammary Epithelial Cells. Suzanne E. Fenton1 and Lewis G. Sheffield2. 1U.S. Environmental ProtectionAgency, MD-72, Research Triangle Park, NC 27711, and

  3. The pluripotency factor Nanog is directly upregulated by the androgen receptor in prostate cancer cells.

    Science.gov (United States)

    Kregel, Steven; Szmulewitz, Russell Z; Vander Griend, Donald J

    2014-11-01

    The Androgen Receptor (AR) is a nuclear hormone receptor that functions as a critical oncogene in all stages of prostate cancer progression, including progression to castration-resistance following androgen-deprivation therapy. Thus, identifying and targeting critical AR-regulated genes is one potential method to block castration-resistant cancer proliferation. Of particular importance are transcription factors that regulate stem cell pluripotency; many of these genes are emerging as critical oncogenes in numerous tumor cell types. Of these, Nanog has been previously shown to increase the self-renewal and stem-like properties of prostate cancer cells. Thus, we hypothesized that Nanog is a candidate AR target gene that may impart castration-resistance. We modulated AR signaling in LNCaP prostate cancer cells and assayed for Nanog expression. Direct AR binding to the NANOG promoter was tested using AR Chromatin Immunoprecipation (ChIP) and analyses of publically available AR ChIP-sequencing data-sets. Nanog over-expressing cells were analyzed for cell growth and cytotoxicity in response to the AR antagonist enzalutamide and the microtubule stabilizing agent docetaxel. AR signaling upregulates Nanog mRNA and protein. AR binds directly to the NANOG promoter, and was not identified within 75 kb of the NANOGP8 pseudogene, suggesting the NANOG gene locus was preferentially activated. Nanog overexpression in LNCaP cells increases overall growth, but does not increase resistance to enzalutamide or docetaxel. Nanog is a novel oncogenic AR target gene in prostate cancer cells, and stable expression of Nanog increases proliferation and growth of prostate cancer cells, but not resistance to enzalutamide or docetaxel. © 2014 Wiley Periodicals, Inc.

  4. Corepressive function of nuclear receptor coactivator 2 in androgen receptor of prostate cancer cells treated with antiandrogen

    International Nuclear Information System (INIS)

    Takeda, Keisuke; Hara, Noboru; Nishiyama, Tsutomu; Tasaki, Masayuki; Ishizaki, Fumio; Tomita, Yoshihiko

    2016-01-01

    Recruitment of cofactors in the interaction of the androgen receptor (AR) and AR ligands plays a critical role in determining androgenic/antiandrogenic effects of the AR ligand on signaling, but the functions of key cofactors, including nuclear receptor coactivator (NCOA), remain poorly understood in prostate cancer cells treated with AR ligands. We examined prostate cancer cell lines LNCaP and VCaP expressing mutated and wild-type ARs, respectively, to clarify the significance of NCOAs in the effect of antiandrogens. Hydroxyflutamide showed antagonistic activity against VCaP and an agonistic effect on LNCaP. Bicalutamide served as an antagonist for both. We analyzed mRNA transcription and protein expression of NCOAs in these cells pretreated with dihydrotestosterone and thereafter treated with the mentioned antiandrogens. Transcriptional silencing of candidate NCOAs and AR was performed using small interfering RNA (siRNA). Cell proliferation was evaluated with MTT assay. LNCaP treated with bicalutamide showed an about four-fold increase in the expression of NCOA2 mRNA compared to those pretreated with dihydrotestosterone alone (P <0.01). In VCaP pretreated with dihydrotestosterone, transcriptions of NCOA2 and NCOA7 were slightly increased with bicalutamide (1.96- and 2.42-fold, respectively) and hydroxyflutamide (1.33-fold in both). With Western blotting, the expression of NCOA2 protein also increased in LNCaP cells treated with bicalutamide compared with that in control cells pretreated with dihydrotestosterone alone. Following silencing with siRNA for NCOA2, PSA levels in media with LNCaP receiving bicalutamide were elevated compared with those in non-silencing controls (101.6 ± 4.2 vs. 87.8 ± 1.4 ng/mL, respectively, P =0.0495). In LNCaP cells treated with dihydrotestosterone and bicalutamide, NCOA2-silencing was associated with a higher proliferation activity compared with non-silencing control and AR-silencing. NCOA2, which has been thought to be recruited

  5. Transcripts of genes encoding reproductive neuroendocrine hormones and androgen receptor in the brain and testis of goldfish exposed to vinclozolin, flutamide, testosterone, and their combinations.

    Science.gov (United States)

    Golshan, Mahdi; Habibi, Hamid R; Alavi, Sayyed Mohammad Hadi

    2016-08-01

    Vinclozolin (VZ) is a pesticide that acts as an anti-androgen to impair reproduction in mammals. However, VZ-induced disruption of reproduction is largely unknown in fish. In the present study, we have established a combination exposure in which adult goldfish were exposed to VZ (30 and 100 μg/L), anti-androgen flutamide (Flu, 300 μg/L), and androgen testosterone (T, 1 μg/L) to better understand effects of VZ on reproductive endocrine system. mRNA levels of kisspeptin (kiss-1 and kiss-2) and its receptor (gpr54), salmon gonadotropin-releasing hormone (gnrh3) and androgen receptor (ar) in the mid-brain, and luteinizing hormone receptor (lhr) in the testis were analyzed and compared with those of control following 10 days of exposure. kiss-1 mRNA level was increased in goldfish exposed to 100 µg/L VZ and to Flu, while kiss-2 mRNA level was increased following exposure to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. gpr54 mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu and 100 µg/L VZ with T. gnrh3 mRNA level was increased in goldfish exposed to 100 µg/L VZ, to Flu, and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. The mid-brain ar mRNA level was increased in goldfish exposed to Flu and to combinations of 30 µg/L VZ with Flu, 100 µg/L VZ with T, and Flu with T. Testicular lhr mRNA level was increased in goldfish exposed to Flu and to combination of 30 µg/L VZ with Flu. These results suggest that VZ and Flu are capable of interfering with kisspeptin and GnRH systems to alter pituitary and testicular horonal functions in adult goldfish and the brain ar mediates VZ-induced disruption of androgen production.

  6. Disruption of δ-opioid receptor phosphorylation at threonine 161 attenuates morphine tolerance in rats with CFA-induced inflammatory hypersensitivity.

    Science.gov (United States)

    Chen, Hai-Jing; Xie, Wei-Yan; Hu, Fang; Zhang, Ying; Wang, Jun; Wang, Yun

    2012-04-01

    Our previous study identified Threonine 161 (Thr-161), located in the second intracellular loop of the δ-opioid receptor (DOR), as the only consensus phosphorylation site for cyclin-dependent kinase 5 (Cdk5). The aim of this study was to assess the function of DOR phosphorylation by Cdk5 in complete Freund's adjuvant (CFA)-induced inflammatory pain and morphine tolerance. Dorsal root ganglion (DRG) neurons of rats with CFA-induced inflammatory pain were acutely dissociated and the biotinylation method was used to explore the membrane localization of phosphorylated DOR at Thr-161 (pThr-161-DOR), and paw withdrawal latency was measured after intrathecal delivery of drugs or Tat-peptide, using a radiant heat stimulator in rats with CFA-induced inflammatory pain. Both the total amount and the surface localization of pThr-161-DOR were significantly enhanced in the ipsilateral DRG following CFA injection. Intrathecal delivery of the engineered Tat fusion-interefering peptide corresponding to the second intracellular loop of DOR (Tat-DOR-2L) increased inflammatory hypersensitivity, and inhibited DOR- but not µ-opioid receptor-mediated spinal analgesia in CFA-treated rats. However, intrathecal delivery of Tat-DOR-2L postponed morphine antinociceptive tolerance in rats with CFA-induced inflammatory pain. Phosphorylation of DOR at Thr-161 by Cdk5 attenuates hypersensitivity and potentiates morphine tolerance in rats with CFA-induced inflammatory pain, while disruption of the phosphorylation of DOR at Thr-161 attenuates morphine tolerance.

  7. Characterization of phosphorylated beta-adrenergic receptors from desensitized turkey erythrocytes

    International Nuclear Information System (INIS)

    Rebar, R.; Crooke, S.T.; Stadel, J.M.

    1986-01-01

    Catecholamine-induced desensitization of turkey erythrocyte (TE) adenylate cyclase results in a 40-50 percent decrease in agonist stimulated cyclase activity. Desensitization is accompanied by decreased mobility on SDS-PAGE of beta-adrenergic receptor (BAR) proteins photoaffinity labeled with [ 125 I]-p-azidobenzylcarazolol compared to control. Using a low crosslinked gel, the M/sub r/ = 42,000 band of BAR from desensitized TE was further resolved into a doublet compared to a single M/sub r/ = 38,000 band for control. The formation of the doublet appears to correlate with the amount of adenylate cyclase desensitization. Preincubating TE for 20 hr at 37 0 C with 32 P-/sub i/ labels BAR. 32 P-BAR was partially purified by affinity chromatography over alprenolol-Sepharose. Limited digest peptide maps of 32 P-BAR using papain identified a unique peptide (M/sub r/ = 2800) from BAR of desensitized TE which was absent in control. This unique 32 P-peptide was found only in the upper band of the doublet of BAR from desensitized TE. These data indicate that BAR is not uniformly phosphorylated following agonist-induced desensitization of TE and identify a peptide of BAR which is a site of phosphorylation correlating with desensitization of TE adenylate cyclase

  8. Androgen receptor or estrogen receptor-beta blockade alters DHEA-, DHT-, and E(2)-induced proliferation and PSA production in human prostate cancer cells.

    Science.gov (United States)

    Arnold, Julia T; Liu, Xunxian; Allen, Jeffrey D; Le, Hanh; McFann, Kimberly K; Blackman, Marc R

    2007-08-01

    Dehydroepiandrosterone (DHEA) is an endogenous steroid that is metabolized to androgens and/or estrogens in the human prostate. DHEA levels decline with age, and use of DHEA supplements to retard the aging process is of unproved effectiveness and safety. LNCaP and LAPC-4 prostate cancer cells were used to determine whether DHEA-modulated proliferation and prostate specific antigen (PSA) production were mediated via the androgen receptor (AR) and/or ERbeta. Cells were treated with DHEA, DHT, or E(2) and antagonists to AR (Casodex-bicalutamide) or ER (ICI 182,780) or siRNA to the respective receptors. Proliferation was assessed by MTT assay and PSA mRNA and protein secretion were measured by quantitative real-time PCR and ELISA. Associations of AR and ERbeta were analyzed by co-immunoprecipitation studies and fluorescent confocal microscopy. DHEA-, T-, and E(2)-induced proliferation of LNCaP cells was blunted by Casodex but not by ICI treatment. In LNCaP cells, Casodex and ICI suppressed hormone-induced PSA production. In LAPC-4 cells, DHT-stimulated PSA mRNA was inhibited by Casodex and ICI, and the minimal stimulation by DHEA was inhibited by ICI. Use of siRNAs confirmed involvement of AR and ERbeta in hormone-induced PSA production while AR-ERbeta co-association was suggested by immunoprecipitation and nuclear co-localization. These findings support involvement of both AR and ERbeta in mediating DHEA-, DHT-, and E(2)-induced PSA expression in prostate cancer cells. (c) 2007 Wiley-Liss, Inc.

  9. Selective androgen receptor modulators for the prevention and treatment of muscle wasting associated with cancer.

    Science.gov (United States)

    Dalton, James T; Taylor, Ryan P; Mohler, Michael L; Steiner, Mitchell S

    2013-12-01

    This review highlights selective androgen receptor modulators (SARMs) as emerging agents in late-stage clinical development for the prevention and treatment of muscle wasting associated with cancer. Muscle wasting, including a loss of skeletal muscle, is a cancer-related symptom that begins early in the progression of cancer and affects a patient's quality of life, ability to tolerate chemotherapy, and survival. SARMs increase muscle mass and improve physical function in healthy and diseased individuals, and potentially may provide a new therapy for muscle wasting and cancer cachexia. SARMs modulate the same anabolic pathways targeted with classical steroidal androgens, but within the dose range in which expected effects on muscle mass and function are seen androgenic side-effects on prostate, skin, and hair have not been observed. Unlike testosterone, SARMs are orally active, nonaromatizable, nonvirilizing, and tissue-selective anabolic agents. Recent clinical efficacy data for LGD-4033, MK-0773, MK-3984, and enobosarm (GTx-024, ostarine, and S-22) are reviewed. Enobosarm, a nonsteroidal SARM, is the most well characterized clinically, and has consistently demonstrated increases in lean body mass and better physical function across several populations along with a lower hazard ratio for survival in cancer patients. Completed in May 2013, results for the Phase III clinical trials entitled Prevention and treatment Of muscle Wasting in patiEnts with Cancer1 (POWER1) and POWER2 evaluating enobosarm for the prevention and treatment of muscle wasting in patients with nonsmall cell lung cancer will be available soon, and will potentially establish a SARM, enobosarm, as the first drug for the prevention and treatment of muscle wasting in cancer patients.

  10. Androgen receptor CAG repeat polymorphism and hypothalamic-pituitary-gonadal function in Filipino young adult males

    Science.gov (United States)

    Ryan, Calen P.; McDade, Thomas W; Gettler, Lee T.; Eisenberg, Dan T.A.; Rzhetskaya, Margarita; Hayes, M. Geoffey; Kuzawa, Christopher W.

    2016-01-01

    Objectives Testosterone (T), the primary androgenic hormone in males, is stimulated through pulsatile secretion of LH and regulated through negative feedback inhibition at the hypothalamus and pituitary. The hypothalamic-pituitary-gonadal (HPG) axis also controls sperm production through the secretion of follicle-stimulating hormone (FSH). Negative feedback in the HPG axis is achieved in part through the binding of T to the androgen receptor (AR), which contains a highly variable trinucleotide repeat polymorphism (AR-CAGn). The number of repeats in the AR-CAGn inversely correlates with transcriptional activity of the AR. Thus, we predicted longer AR-CAGn to be associated with higher T, LH, and FSH levels. Methods We examined the relationship between AR-CAGn and total plasma T, LH, and FSH, as well as 'bioavailable' morning (AM-T) and evening (PM-T) testosterone in 722 young (21.5 ± 0.5 years) Filipino males. Results There was no relationship between AR-CAGn and total T, AM-T, or LH (P > 0.25 for all). We did observe a marginally non-significant (P = 0.066) correlation between AR-CAGn and PM-T in the predicted direction, and a negative correlation between AR-CAGn and FSH (P = 0.005). Conclusions Our results both support and differ from previous findings in this area, and study parameters that differ between our study and others, such as participant age, sample time, and the role of other hormones should be considered when interpreting our findings. While our data point to a modest effect of AR-CAGn on HPG regulation at best, the AR-CAGn may still affect somatic traits by regulating androgenic activity at peripheral tissues. PMID:27417274

  11. Androgen receptor variant-7: an important predictive biomarker in castrate resistant prostate cancer

    Directory of Open Access Journals (Sweden)

    Oliver Sartor

    2015-06-01

    Full Text Available The recent manuscript in New England Journal of Medicine by Antonarakis et al. [1] has important clinical implications. This study evaluates mRNA expression of a particular androgen receptor splice variant-7 (AR-V7, in circulating tumor cells (CTCs from metastatic castrate-resistant prostate cancer (mCRPC patients receiving enzalutamide or abiraterone. The findings were striking, none of the 18 patients with detectable AR-V7 in CTCs had prostate-specific antigen (PSA responses. Further, the median time to PSA progression after enzalutamide or abiraterone treatment was only 1.3-1.4 months in AR-V7-positive patients as compared to 5.3-6.1 months in AR-V7 negative patients. AR-V7 in CTCs was also associated with shorter survival.

  12. Transient gestational and neonatal hypothyroidism-induced specific changes in androgen receptor expression in skeletal and cardiac muscles of adult rat.

    Science.gov (United States)

    Annapoorna, K; Anbalagan, J; Neelamohan, R; Vengatesh, G; Stanley, J; Amudha, G; Aruldhas, M M

    2013-03-01

    The present study aims to identify the association between androgen status and metabolic activity in skeletal and cardiac muscles of adult rats with transient gestational/neonatal-onset hypothyroidism. Pregnant and lactating rats were made hypothyroid by exposing to 0.05% methimazole in drinking water; gestational exposure was from embryonic day 9-14 (group II) or 21 (group III), lactational exposure was from postnatal day 1-14 (group IV) or 29 (group V). Serum was collected for hormone assay. Androgen receptor status, Glu-4 expression, and enzyme activities were assessed in the skeletal and cardiac muscles. Serum testosterone and estradiol levels decreased in adult rats of groups II and III, whereas testosterone remained normal but estradiol increased in group IV and V, when compared to coeval control. Androgen receptor ligand binding activity increased in both muscle phenotypes with a consistent increase in the expression level of its mRNA and protein expressions except in the forelimb of adult rats with transient hypothyroidism (group II-V). Glut-4 expression remained normal in skeletal and cardiac muscle of experimental rats. Specific activity of hexokinase and lactate dehydrogenase increased in both muscle phenotypes whereas, creatine kinase activity increased in skeletal muscles alone. It is concluded that transient gestational/lactational exposure to methimazole results in hypothyroidism during prepuberal life whereas it increases AR status and glycolytic activity in skeletal and cardiac muscles even at adulthood. Thus, the present study suggests that euthyroid status during prenatal and early postnatal life is essential to have optimal AR status and metabolic activity at adulthood. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Effects of extract of Buddleja officinalis eye drops on androgen receptors of lacrimal gland cells of castrated rats with dry eye.

    Science.gov (United States)

    Peng, Qing-Hua; Yao, Xiao-Lei; Wu, Quan-Long; Tan, Han-Yu; Zhang, Jing-Rong

    2010-01-01

    To evaluate the effects of the extract of Buddleja officinalis eye drops in basic tears secretory volume, tear film stability, expression of androgen receptors (AR) in castrated rats with dry eye, and to investigate the therapeutic effects of the extract of Buddleja officinalis on dry eye caused by gonadal hormones level imbalance. Forty-five Wistar masculinity rats were divided at random into nine groups, including normal groups (A1, A2 and A3); model groups (B1, B2 and B3); therapy groups with extract of Buddleja officinalis eye drops (C1, C2 and C3). The "1" stood for being fed for 1 month, and "2" for 2 months, and "3" for 3 months. The dry eye model was established with orchiectomy on groups B and C. Group C was treated with Buddleja officinalis extract eye drops for one month. All rats were checked with Schirmer I test (SIT) and tear film break-up time (BUT). Expression of AR was analyzed by flow cytometer (FCM). The SIT value of group C was significantly higher than that of group B (PBuddleja officinalis is the flavonoids that can significantly inhibit happening of dry eye of rat after androgen level lowered. Its mechanism is like androgen's and it can display androgen-like activity to keep basic tears secretory volume and tear film stability.

  14. Androgen receptor in early apoptotic follicles in the porcine ovary at pregnancy.

    Directory of Open Access Journals (Sweden)

    Zbigniew Tabarowski

    2006-09-01

    Full Text Available Localization of androgen receptor (AR was investigated in ovarian follicles developing and undergoing atresia during pregnancy in the pig. Immunohistochemical staining was conducted on ovarian antral follicles isolated on different days of gestation: 10, 18, 32, 50, 70, and 90. Paraffin sections were also subjected to in situ DNA labeling. TUNEL staining revealed the presence of positive follicles on all days of pregnancy but the amount of atretic follicles increased with time. However, even on day 90 of gestation many follicles were normal, with no signs of atresia. In atretic follicles, apoptotic cells were localized predominantly in the granulosa while theca was much less affected. Atretic follicles with many apoptotic cells were negative for AR. Nuclear immunostaining for AR was positive in follicles with limited amount of apoptotic cells. The same relationship was observed in ovarian follicles isolated at various days of pregnancy.

  15. Neurotensin-induced Erk1/2 phosphorylation and growth of human colonic cancer cells are independent from growth factors receptors activation

    Energy Technology Data Exchange (ETDEWEB)

    Massa, Fabienne; Tormo, Aurelie; Beraud-Dufour, Sophie; Coppola, Thierry [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France); Mazella, Jean, E-mail: mazella@ipmc.cnrs.fr [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France)

    2011-10-14

    Highlights: {yields} We compare intracellular pathways of NT and EGF in HT29 cells. {yields} NT does not transactivate EGFR. {yields} Transactivation of EGFR is not a general rule in cancer cell growth. -- Abstract: Neurotensin (NT) promotes the proliferation of human colonic cancer cells by undefined mechanisms. We already demonstrated that, in the human colon adenocarcinoma cell line HT29, the effects of NT were mediated by a complex formed between the NT receptor-1 (NTSR1) and-3 (NTSR3). Here we examined cellular mechanisms that led to NT-induced MAP kinase phosphorylation and growth factors receptors transactivation in colonic cancer cells and proliferation in HT29 cells. With the aim to identify upstream signaling involved in NT-elicited MAP kinase activation, we found that the stimulatory effects of the peptide were totally independent from the activation of the epidermal growth factor receptor (EGFR) both in the HT29 and the HCT116 cells. NT was unable to promote phosphorylation of EGFR and to compete with EGF for its binding to the receptor. Pharmacological approaches allowed us to differentiate EGF and NT signaling in HT29 cells since only NT activation of Erk1/2 was shown to be sensitive to PKC inhibitors and since only NT increased the intracellular level of calcium. We also observed that NT was not able to transactivate Insulin-like growth factor receptor. Our findings indicate that, in the HT29 and HCT116 cell lines, NT stimulates MAP kinase phosphorylation and cell growth by a pathway which does not involve EGF system but rather NT receptors which transduce their own intracellular effectors. These results indicate that depending on the cell line used, blocking EGFR is not the general rule to inhibit NT-induced cancer cell proliferation.

  16. Recent progress in the development of protein-protein interaction inhibitors targeting androgen receptor-coactivator binding in prostate cancer.

    Science.gov (United States)

    Biron, Eric; Bédard, François

    2016-07-01

    The androgen receptor (AR) is a key regulator for the growth, differentiation and survival of prostate cancer cells. Identified as a primary target for the treatment of prostate cancer, many therapeutic strategies have been developed to attenuate AR signaling in prostate cancer cells. While frontline androgen-deprivation therapies targeting either the production or action of androgens usually yield favorable responses in prostate cancer patients, a significant number acquire treatment resistance. Known as the castration-resistant prostate cancer (CRPC), the treatment options are limited for this advanced stage. It has been shown that AR signaling is restored in CRPC due to many aberrant mechanisms such as AR mutations, amplification or expression of constitutively active splice-variants. Coregulator recruitment is a crucial regulatory step in AR signaling and the direct blockade of coactivator binding to AR offers the opportunity to develop therapeutic agents that would remain effective in prostate cancer cells resistant to conventional endocrine therapies. Structural analyses of the AR have identified key surfaces involved in protein-protein interaction with coregulators that have been recently used to design and develop promising AR-coactivator binding inhibitors. In this review we will discuss the design and development of small-molecule inhibitors targeting the AR-coactivator interactions for the treatment of prostate cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Homologous desensitization of adenylate cyclase: the role of β-adrenergic receptor phosphorylation and dephosphorylation

    International Nuclear Information System (INIS)

    Sibley, D.R.; Strasser, R.H.; Daniel, K.; Lefkowitz, R.J.

    1986-01-01

    The authors utilized the frog erythrocyte (FE) as a β-adreneric receptor (βAR) model system in which to study homologous desensitization. Preincubation with isoproterenol (ISO) leads to a 50% decline in ISO-stimulated adenylate cyclase (AC) activity without significant changes in basal, PGE 1 -, NaF-, GppNHp-, forskolin-, or MnCl 2 -stimulated AC activities. ISO treatment also induces the sequestration of βAR from the cell surface as evidenced by a 35% decline in [ 3 H]CGP-12177 binding sites on the surface of intact FE. Treatment of intact FE with ISO also promotes βAR phosphorylation to 2 mol PO 4 /mol of βAR. At 25 0 C, the time courses of ISO-induced AC desensitization, βAR sequestration and βAR phosphorylation are identical occurring without a lag and exhibiting a t 1/2 of 30 min and a maximal response at 2.5 hrs. The sequestered βAR can be partially recovered upon cell lysis in a light membrane fraction (LMF), separable from the plasma membranes using sucrose gradients or differential centrifugation. βAR phosphorylation is reversed in the sequestered LMF exhibiting a PO 4 /βAR stoichiometry of 0.7 mol/mol - similar to that observed under basal conditions. These data suggest that phosphorylation of βAR in the plasma membrane promotes their translocation away from the cell surface into a sequestered membrane domain where the phosphorylation is reversed, thus, enabling the return of βAR back to the cell surface and recoupling with AC

  18. PEST Motif Serine and Tyrosine Phosphorylation Controls Vascular Endothelial Growth Factor Receptor 2 Stability and Downregulation ▿

    Science.gov (United States)

    Meyer, Rosana D.; Srinivasan, Srimathi; Singh, Amrik J.; Mahoney, John E.; Gharahassanlou, Kobra Rezazadeh; Rahimi, Nader

    2011-01-01

    The internalization and degradation of vascular endothelial growth factor receptor 2 (VEGFR-2), a potent angiogenic receptor tyrosine kinase, is a central mechanism for the regulation of the coordinated action of VEGF in angiogenesis. Here, we show that VEGFR-2 is ubiquitinated in response to VEGF, and Lys 48-linked polyubiquitination controls its degradation via the 26S proteosome. The degradation and ubiquitination of VEGFR-2 is controlled by its PEST domain, and the phosphorylation of Ser1188/Ser1191 is required for the ubiquitination of VEGFR-2. F-box-containing β-Trcp1 ubiquitin E3 ligase is recruited to S1188/S1191 VEGFR-2 and mediates the ubiquitination and degradation of VEGFR-2. The PEST domain also controls the activation of p38 mitogen-activated protein kinase (MAPK) through phospho-Y1173. The activation of p38 stabilizes VEGFR-2, and its inactivation accelerates VEGFR-2 downregulation. The VEGFR-2-mediated activation of p38 is established through the protein kinase A (PKA)/MKK6 pathway. PKA is recruited to VEGFR-2 through AKAP1/AKAP149, and its phosphorylation requires Y1173 of VEGFR-2. The study has identified a unique mechanism in which VEGFR-2 stability and degradation is modulated. The PEST domain acts as a dual modulator of VEGFR-2; the phosphorylation of S1188/S1191 controls ubiquitination and degradation via β-Trcp1, where the phosphorylation of Y1173 through PKA/p38 MAPK controls the stability of VEGFR-2. PMID:21402774

  19. Nucleoporin 62 and Ca(2+)/calmodulin dependent kinase kinase 2 regulate androgen receptor activity in castrate resistant prostate cancer cells.

    Science.gov (United States)

    Karacosta, Loukia G; Kuroski, Laura A; Hofmann, Wilma A; Azabdaftari, Gissou; Mastri, Michalis; Gocher, Angela M; Dai, Shuhang; Hoste, Allen J; Edelman, Arthur M

    2016-02-15

    Re-activation of the transcriptional activity of the androgen receptor (AR) is an important factor mediating progression from androgen-responsive to castrate-resistant prostate cancer (CRPC). However, the mechanisms regulating AR activity in CRPC remain incompletely understood. Ca(2+) /calmodulin-dependent kinase kinase (CaMKK) 2 was previously shown to regulate AR activity in androgen-responsive prostate cancer cells. Our objective was to further explore the basis of this regulation in CRPC cells. The abundance of CaMKK2 in nuclear fractions of androgen-responsive prostate cancer and CRPC, cells were determined by subcellular fractionation and Western blotting. CaMKK2 association with nuclear pore complexes (NPCs) and nucleoporins (Nups) including Nup62, were imaged by structured illumination and super-resolution fluorescence microscopy and co-immunoprecipitation, respectively. The abundance and subcellular localization of CaMKK2 and Nup62 in human clinical specimens of prostate cancer was visualized by immunohistochemistry. The role of Nups in the growth and viability of CRPC cells was assessed by RNA interference and cell counting. The involvement of CaMKK2 and Nup62 in regulating AR transcriptional activity was addressed by RNA interference, chromatin immunoprecipitation, androgen response element reporter assay, and Western blotting. CaMKK2 was expressed at higher levels in the nuclear fraction of CPRC C4-2 cells, than in that of androgen-responsive LNCaP cells. In C4-2 cells, CaMKK2 associated with NPCs of the nuclear envelope and physically interacted with Nup62. CaMKK2 and Nup62 demonstrated pronounced, and similar increases in both expression and perinuclear/nuclear localization in human clinical specimens of advanced prostate cancer relative to normal prostate. Knockdown of Nup62, but not of Nups, 98 or 88, reduced growth and viability of C4-2 cells. Knockdown of Nup62 produced a greater reduction of the growth and viability of C4-2 cells than of non

  20. Transition from androgenic to neurosteroidal action of 5α-androstane-3α, 17β-diol through the type A γ-aminobutyric acid receptor in prostate cancer progression.

    Science.gov (United States)

    Xia, Ding; Lai, Doan V; Wu, Weijuan; Webb, Zachary D; Yang, Qing; Zhao, Lichao; Yu, Zhongxin; Thorpe, Jessica E; Disch, Bryan C; Ihnat, Michael A; Jayaraman, Muralidharan; Dhanasekaran, Danny N; Stratton, Kelly L; Cookson, Michael S; Fung, Kar-Ming; Lin, Hsueh-Kung

    2018-04-01

    Androgen ablation is the standard of care prescribed to patients with advanced or metastatic prostate cancer (PCa) to slow down disease progression. Unfortunately, a majority of PCa patients under androgen ablation progress to castration-resistant prostate cancer (CRPC). Several mechanisms including alternative intra-prostatic androgen production and androgen-independent androgen receptor (AR) activation have been proposed for CRPC progression. Aldo-keto reductase family 1 member C3 (AKR1C3), a multi-functional steroid metabolizing enzyme, is specifically expressed in the cytoplasm of PCa cells; and positive immunoreactivity of the type A γ-aminobutyric acid receptor (GABA A R), an ionotropic receptor and ligand-gated ion channel, is detected on the membrane of PCa cells. We studied a total of 72 radical prostatectomy cases by immunohistochemistry, and identified that 21 cases exhibited positive immunoreactivities for both AKR1C3 and GABA A R. In the dual positive cancer cases, AKR1C3 and GABA A R subunit α 1 were either expressed in the same cells or in neighboring cells. Among several possible substrates, AKR1C3 reduces 5α-dihydrotesterone (DHT) to form 5α-androstane-3α, 17β-diol (3α-diol). 3α-diol is a neurosteroid that acts as a positive allosteric modulator of the GABA A R in the central nervous system (CNS). We examined the hypothesis that 3α-diol-regulated pathological effects in the prostate are GABA A R-dependent, but are independent of the AR. In GABA A R-positive, AR-negative human PCa PC-3 cells, 3α-diol significantly stimulated cell growth in culture and the in ovo chorioallantoic membrane (CAM) xenograft model. 3α-diol also up-regulated expression of the epidermal growth factor (EGF) family of growth factors and activation of EGF receptor (EGFR) and Src as measured by quantitative polymerase chain reaction and immunoblotting, respectively. Inclusion of GABA A R antagonists reversed 3α-diol-stimulated tumor cell growth, expression of EGF

  1. GGC and StuI polymorphism on the androgen receptor gene in endometrial cancer patients

    International Nuclear Information System (INIS)

    Sasaki, Masahiro; Karube, Akihiro; Karube, Yuko; Watari, Michiko; Sakuragi, Noriaki; Fujimoto, Seiichiro; Dahiya, Rajvir

    2005-01-01

    Androgens have an anti-proliferative effect on endometrial cells. Human androgen receptor (AR) gene contains two polymorphic short tandem repeats of GGC and CAG, and a single-nucleotide polymorphism on exon 1 that is recognized by the restriction enzyme, StuI. Prior studies have shown that the lengths of the CAG repeat are inversely and linearly related to AR activity and associated with endometrial cancer. However, little is known about the GGC repeat and the StuI polymorphism of the AR gene. Thus, we investigated whether these AR polymorphisms are risk factors for endometrial cancer. To test this hypothesis, the genetic distributions of these polymorphisms were investigated in blood samples from endometrial cancer patients and healthy controls. The allelic and genotyping profiles were analyzed by polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism (PCR-RFLP), and direct DNA sequencing, and analyzed statistically. The GGC repeat was significantly longer in endometrial cancer patients as compared to normal healthy controls. In general, an increased risk of endometrial cancer was found with increasing GGC repeat. The relative risk for the 17 GGC repeat was greater than 4, as compared to controls. However, the StuI polymorphism was not significantly different between patients and controls. The findings suggest that increased numbers of GGC repeat on the AR gene may be a risk factor for endometrial cancer

  2. Non-Coding RNAs in Castration-Resistant Prostate Cancer: Regulation of Androgen Receptor Signaling and Cancer Metabolism.

    Science.gov (United States)

    Shih, Jing-Wen; Wang, Ling-Yu; Hung, Chiu-Lien; Kung, Hsing-Jien; Hsieh, Chia-Ling

    2015-12-04

    Hormone-refractory prostate cancer frequently relapses from therapy and inevitably progresses to a bone-metastatic status with no cure. Understanding of the molecular mechanisms conferring resistance to androgen deprivation therapy has the potential to lead to the discovery of novel therapeutic targets for type of prostate cancer with poor prognosis. Progression to castration-resistant prostate cancer (CRPC) is characterized by aberrant androgen receptor (AR) expression and persistent AR signaling activity. Alterations in metabolic activity regulated by oncogenic pathways, such as c-Myc, were found to promote prostate cancer growth during the development of CRPC. Non-coding RNAs represent a diverse family of regulatory transcripts that drive tumorigenesis of prostate cancer and various other cancers by their hyperactivity or diminished function. A number of studies have examined differentially expressed non-coding RNAs in each stage of prostate cancer. Herein, we highlight the emerging impacts of microRNAs and long non-coding RNAs linked to reactivation of the AR signaling axis and reprogramming of the cellular metabolism in prostate cancer. The translational implications of non-coding RNA research for developing new biomarkers and therapeutic strategies for CRPC are also discussed.

  3. Identification of Androgen Receptor-Specific Enhancer RNAs

    Science.gov (United States)

    2017-08-01

    SUPPLEMENTARY NOTES 14. ABSTRACT The major goal of this application is to determine whether prostate cancer cells express enhancer RNAs in response to...androgen treatment such that these enhancer RNAs may serve as novel biomarkers for prostate cancer diagnosis and prognosis. There are two Tasks in...biomarkers or therapeutic targets for prostate cancer , especially for castration resistant prostate cancer . 15. SUBJECT TERMS lncRNA, eRNA, biomarker

  4. Sequence of the intron/exon junctions of the coding region of the human androgen receptor gene and identification of a point mutation in a family with complete androgen insensitivity

    International Nuclear Information System (INIS)

    Lubahn, D.B.; Simental, J.A.; Higgs, H.N.; Wilson, E.M.; French, F.S.; Brown, T.R.; Migeon, C.J.

    1989-01-01

    Androgens act through a receptor protein (AR) to mediate sex differentiation and development of the male phenotype. The authors have isolated the eight exons in the amino acid coding region of the AR gene from a human X chromosome library. Nucleotide sequences of the AR gene intron/exon boundaries were determined for use in designing synthetic oligonucleotide primers to bracket coding exons for amplification by the polymerase chain reaction. Genomic DNA was amplified from 46, XY phenotypic female siblings with complete androgen insensitivity syndrome. AR binding affinity for dihydrotestosterone in the affected siblings was lower than in normal males, but the binding capacity was normal. Sequence analysis of amplified exons demonstrated within the AR steroid-binding domain (exon G) a single guanine to adenine mutation, resulting in replacement of valine with methionine at amino acid residue 866. As expected, the carrier mother had both normal and mutant AR genes. Thus, a single point mutation in the steroid-binding domain of the AR gene correlated with the expression of an AR protein ineffective in stimulating male sexual development

  5. Complete Androgen Insensitivity Syndrome: A Rare Case of Disorder of Sex Development

    Directory of Open Access Journals (Sweden)

    Alfonsa Pizzo

    2013-01-01

    Full Text Available Androgen Insensitivity Syndrome (AIS could be considered as a disease that causes resistance to androgens actions, influencing both the morphogenesis and differentiation of the body structures, and systems in which this hormone exerts its effects. It depends on an X-linked mutations in the Androgen Receptor (AR gene that express a variety of phenotypes ranging from male infertility to completely normal female external genitalia. The clinical phenotypes of AIS could vary and be classified into three categories, as complete (CAIS, partial (PAIS, and mild (MAIS forms, according to the severity of androgen resistance. We will describe a case of CAIS in a 16-year-old patient.

  6. Androgen receptor-beta mRNA levels in different tissues in breeding and post-breeding male and female sticklebacks, Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Hoffmann Erik

    2012-03-01

    Full Text Available Abstract Background Androgens induce male characters by activating androgen receptors (AR. Previous quantitative studies on AR in fishes have been limited to few tissues and/or a single season/reproductive state. The aim of this investigation was to study the possible role of AR-beta expression levels in the control of male traits in the three-spined stickleback. To that end, AR-beta expression levels in major tissues in breeding and post-breeding male and female sticklebacks were examined. Methods AR-beta mRNA levels were quantified in ten tissues; eye, liver, axial muscle, heart, brain, intestine, ovary, testis, kidney and pectoral muscle in six breeding and post-breeding males and females using reverse transcription quantitative PCR. Results Breeding in contrast to post-breeding males built nests and showed secondary sexual characters (e.g. kidney hypertrophy and elevated androgen levels. Post-breeding females had lower ovarian weights and testosterone levels than breeding females. AR-beta was expressed in all studied tissues in both sexes and reproductive states with the highest expression in the gonads and in the kidneys. The kidney is an androgen target organ in sticklebacks, from which breeding males produce the protein spiggin, which is used in nest-building. There was also high AR-beta expression in the intestine, an organ that appears to take over hyperosmo-regulation in fresh water when the kidney hypertrophies in mature males and largely loses this function. The only tissue that showed effects of sex or reproductive state on AR-beta mRNA levels was the kidneys, where post-breeding males displayed higher AR-beta mRNA levels than breeding males. Conclusion The results indicate that changes in AR-beta mRNA levels play no or little role in changes in androgen dependent traits in the male stickleback.

  7. Three novel and two known androgen receptor gene mutations ...

    Indian Academy of Sciences (India)

    BALACHANDRAN SARANYA

    with androgen insensitivity syndrome in sex-reversed XY female patients. BALACHANDRAN ..... from the subjects, their family members and controls who participated in the ..... disease, 1st edition. Springer Science + Business Media, New.

  8. A new dawn for androgens: Novel lessons from 11-oxygenated C19 steroids.

    Science.gov (United States)

    Pretorius, Elzette; Arlt, Wiebke; Storbeck, Karl-Heinz

    2017-02-05

    The abundant adrenal C19 steroid 11β-hydroxyandrostenedione (11OHA4) has been written off as a dead-end product of adrenal steroidogenesis. However, recent evidence has demonstrated that 11OHA4 is the precursor to the potent androgenic 11-oxygenated steroids, 11-ketotestosterone and 11-ketodihydrotestosterone, that bind and activate the human androgen receptor similarly to testosterone and DHT. The significance of this discovery becomes apparent when considering androgen dependent diseases such as castration resistant prostate cancer and diseases associated with androgen excess, e.g. congenital adrenal hyperplasia and polycystic ovary syndrome. In this review we describe the production and metabolism of 11-oxygenated steroids. We subsequently discuss their androgenic activity and highlight the putative role of these androgens in disease states. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Combined exposure to anti-androgens causes markedly increased frequencies of hypospadias in the rat

    DEFF Research Database (Denmark)

    Christiansen, Sofie; Scholze, M.; Petersen, Marta Axelstad

    2008-01-01

    of several anti-androgenic chemicals. In a mixture (MIX) study with three androgen receptor antagonists, vinclozolin, flutamide and procymidone, rats were gavaged during gestation and lactation with several doses of a MIX of the three chemicals or the chemicals alone. External malformations of the male...

  10. Prenatal androgen excess programs metabolic derangements in pubertal female rats.

    Science.gov (United States)

    Yan, Xiaonan; Dai, Xiaonan; Wang, Jing; Zhao, Nannan; Cui, Yugui; Liu, Jiayin

    2013-04-01

    Owing to the heterogeneity in the clinical symptoms of polycystic ovary syndrome (PCOS), the early pathophysiological mechanisms of PCOS remain unclear. Clinical, experimental, and genetic evidence supports an interaction between genetic susceptibility and the influence of maternal environment in the pathogenesis of PCOS. To determine whether prenatal androgen exposure induced PCOS-related metabolic derangements during pubertal development, we administrated 5α-dihydrotestosterone (DHT) in pregnant rats and observed their female offspring from postnatal 4 to 8 weeks. The prenatally androgenized (PNA) rats exhibited more numerous total follicles, cystic follicles, and atretic follicles than the controls. Fasting glucose, insulin, leptin levels, and homeostatic model assessment for insulin resistance were elevated in the PNA rats at the age of 5-8 weeks. Following intraperitoneal glucose tolerance tests, glucose and insulin levels did not differ between two groups; however, the PNA rats showed significantly higher 30- and 60-min glucose levels than the controls after insulin stimulation during 5-8 weeks. In addition, prenatal DHT treatment significantly decreased insulin-stimulated phosphorylation of AKT in the skeletal muscles of 6-week-old PNA rats. The abundance of IR substrate 1 (IRS1) and IRS2 was decreased in the skeletal muscles and liver after stimulation with insulin in the PNA group, whereas phosphorylation of insulin-signaling proteins was unaltered in the adipose tissue. These findings validate the contribution of prenatal androgen excess to metabolic derangements in pubertal female rats, and the impaired insulin signaling through IRS and AKT may result in the peripheral insulin resistance during pubertal development.

  11. 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.

  12. Estradiol suppresses tissue androgens and prostate cancer growth in castration resistant prostate cancer

    International Nuclear Information System (INIS)

    Montgomery, Bruce; Nelson, Peter S; Vessella, Robert; Kalhorn, Tom; Hess, David; Corey, Eva

    2010-01-01

    Estrogens suppress tumor growth in prostate cancer which progresses despite anorchid serum androgen levels, termed castration resistant prostate cancers (CRPC), although the mechanisms are unclear. We hypothesize that estrogen inhibits CRPC in anorchid animals by suppressing tumoral androgens, an effect independent of the estrogen receptor. The human CRPC xenograft LuCaP 35V was implanted into orchiectomized male SCID mice and established tumors were treated with placebo, 17β-estradiol or 17β-estradiol and estrogen receptor antagonist ICI 182,780. Effects of 17β-estradiol on tumor growth were evaluated and tissue testosterone (T) and dihydrotestosterone (DHT) evaluated by mass spectrometry. Treatment of LuCaP 35V with 17β-estradiol slowed tumor growth compared to controls (tumor volume at day 21: 785 ± 81 mm 3 vs. 1195 ± 84 mm 3 , p = 0.002). Survival was also significantly improved in animals treated with 17β-estradiol (p = 0.03). The addition of the estrogen receptor antagonist ICI 182,780 did not significantly change survival or growth. 17β-estradiol in the presence and absence of ICI 182,780 suppressed tumor testosterone (T) and dihydrotestosterone (DHT) as assayed by mass spectrometry. Tissue androgens in placebo treated LuCaP 35V xenografts were; T = 0.71 ± 0.28 pg/mg and DHT = 1.73 ± 0.36 pg/mg. In 17β-estradiol treated LuCaP35V xenografts the tissue androgens were, T = 0.20 ± 0.10 pg/mg and DHT = 0.15 ± 0.15 pg/mg, (p < 0.001 vs. controls). Levels of T and DHT in control liver tissue were < 0.2 pg/mg. CRPC in anorchid animals maintains tumoral androgen levels despite castration. 17β-estradiol significantly suppressed tumor T and DHT and inhibits growth of CRPC in an estrogen receptor independent manner. The ability to manipulate tumoral androgens will be critical in the development and testing of agents targeting CRPC through tissue steroidogenesis

  13. Development of androgen-and estrogen-responsive bioassays, members of a panel of human cell line-based highly selective steroid-responsive bioassays

    NARCIS (Netherlands)

    Sonneveld, E.; Jansen, H.J..; Riteco, J.A.C.; Brouwer, A.

    2005-01-01

    We have established highly sensitive and specific androgen and estrogen reporter cell lines which we have named AR (androgen receptor) and ERα (estrogen receptor alpha) CALUX® (Chemically Activated LUciferase eXpression), respectively. Both bioassays are member of a panel of CALUX reporter cell

  14. Androgens regulate gene expression in avian skeletal muscles.

    Directory of Open Access Journals (Sweden)

    Matthew J Fuxjager

    Full Text Available Circulating androgens in adult reproductively active male vertebrates influence a diversity of organ systems and thus are considered costly. Recently, we obtained evidence that androgen receptors (AR are expressed in several skeletal muscles of three passeriform birds, the golden-collared manakin (Manacus vitellinus, zebra finch (Taenopygia guttata, and ochre-bellied flycatcher (Mionectes oleagieus. Because skeletal muscles that control wing movement make up the bulk of a bird's body mass, evidence for widespread effects of androgen action on these muscles would greatly expand the functional impact of androgens beyond their well-characterized effects on relatively discrete targets throughout the avian body. To investigate this issue, we use quantitative PCR (qPCR to determine if androgens alter gene mRNA expression patterns in wing musculature of wild golden-collared manakins and captive zebra finches. In manakins, the androgen testosterone (T up-regulated expression of parvalbumin (PV and insulin-like growth factor I (IGF-I, two genes whose products enhance cellular Ca(2+ cycling and hypertrophy of skeletal muscle fibers. In T-treated zebra finches, the anti-androgen flutamide blunted PV and IGF-I expression. These results suggest that certain transcriptional effects of androgen action via AR are conserved in passerine skeletal muscle tissue. When we examined wing muscles of manakins, zebra finches and ochre-bellied flycatchers, we found that expression of PV and IGF-I varied across species and in a manner consistent with a function for AR-dependent gene regulation. Together, these findings imply that androgens have the potential to act on avian muscle in a way that may enhance the physicality required for successful reproduction.

  15. Growth hormone, interferon-gamma, and leukemia inhibitory factor promoted tyrosyl phosphorylation of insulin receptor substrate-1

    DEFF Research Database (Denmark)

    Argetsinger, L S; Hsu, G W; Myers, M G

    1995-01-01

    ), the principle substrate of the insulin receptor. Tyrosyl phosphorylation of IRS-1 is a critical step in insulin signaling and provides binding sites for proteins with the appropriate Src homology 2 domains, including the 85-kDa regulatory subunit of phosphatidylinositol (PI) 3'-kinase. In 3T3-F442A fibroblasts......., Campbell, G. S., Allevato, G., Billestrup, N., Norstedt, G., and Carter-Su, C. (1994) J. Biol. Chem. 269, 21709-21717). When other cytokines that activate JAK2 were tested for the ability to stimulate the tyrosyl phosphorylation of IRS-1, stimulation was detected with interferon-gamma and leukemia...... to JAK2. GH is also shown to stimulate binding of IRS-1 to the 85-kDa regulatory subunit of PI 3'-kinase. The ability of GH to stimulate tyrosyl phosphorylation of IRS-1 and its association with PI 3'-kinase provides a biochemical basis for responses shared by insulin and GH including the well...

  16. Salivary testosterone and a trinucleotide (CAG) length polymorphism in the androgen receptor gene predict amygdala reactivity in men.

    Science.gov (United States)

    Manuck, Stephen B; Marsland, Anna L; Flory, Janine D; Gorka, Adam; Ferrell, Robert E; Hariri, Ahmad R

    2010-01-01

    In studies employing functional magnetic resonance imaging (fMRI), reactivity of the amygdala to threat-related sensory cues (viz., facial displays of negative emotion) has been found to correlate positively with interindividual variability in testosterone levels of women and young men and to increase on acute administration of exogenous testosterone. Many of the biological actions of testosterone are mediated by intracellular androgen receptors (ARs), which exert transcriptional control of androgen-dependent genes and are expressed in various regions of the brain, including the amygdala. Transactivation potential of the AR decreases (yielding relative androgen insensitivity) with expansion a polyglutamine stretch in the N-terminal domain of the AR protein, as encoded by a trinucleotide (CAG) repeat polymorphism in exon 1 of the X-chromosome AR gene. Here we examined whether amygdala reactivity to threat-related facial expressions (fear, anger) differs as a function of AR CAG length variation and endogenous (salivary) testosterone in a mid-life sample of 41 healthy men (mean age=45.6 years, range: 34-54 years; CAG repeats, range: 19-29). Testosterone correlated inversely with participant age (r=-0.39, p=0.012) and positively with number of CAG repeats (r=0.45, p=0.003). In partial correlations adjusted for testosterone level, reactivity in the ventral amygdala was lowest among men with largest number of CAG repeats. This inverse association was seen in both the right (r(p)=-0.34, pleft (r(p)=-0.32, pdifferences in salivary testosterone, also in right (r=0.40, pleft (r=0.32, pdifferences in salivary testosterone also predicted dorsal amygdala reactivity and did so independently of CAG repeats, it is suggested that androgenic influences within this anatomically distinct region may be mediated, in part, by non-genomic or AR-independent mechanisms.

  17. Small Molecule Antagonists of the Nuclear Androgen Receptor for the Treatment of Castration-Resistant Prostate Cancer.

    Science.gov (United States)

    Johnson, James K; Skoda, Erin M; Zhou, Jianhua; Parrinello, Erica; Wang, Dan; O'Malley, Katherine; Eyer, Benjamin R; Kazancioglu, Mustafa; Eisermann, Kurtis; Johnston, Paul A; Nelson, Joel B; Wang, Zhou; Wipf, Peter

    2016-08-11

    After a high-throughput screening campaign identified thioether 1 as an antagonist of the nuclear androgen receptor, a zone model was developed for structure-activity relationship (SAR) purposes and analogues were synthesized and evaluated in a cell-based luciferase assay. A novel thioether isostere, cyclopropane (1S,2R)-27, showed the desired increased potency and structural properties (stereospecific SAR response, absence of a readily oxidized sulfur atom, low molecular weight, reduced number of flexible bonds and polar surface area, and drug-likeness score) in the prostate-specific antigen luciferase assay in C4-2-PSA-rl cells to qualify as a new lead structure for prostate cancer drug development.

  18. Bone anabolic effects of S-40503, a novel nonsteroidal selective androgen receptor modulator (SARM), in rat models of osteoporosis.

    Science.gov (United States)

    Hanada, Keigo; Furuya, Kazuyuki; Yamamoto, Noriko; Nejishima, Hiroaki; Ichikawa, Kiyonoshin; Nakamura, Tsutomu; Miyakawa, Motonori; Amano, Seiji; Sumita, Yuji; Oguro, Nao

    2003-11-01

    A novel nonsteroidal androgen receptor (AR) binder, S-40503, was successfully generated in order to develop selective androgen receptor modulators (SARMs). We evaluated the binding specificity for nuclear receptors (NRs) and osteoanabolic activities of S-40503 in comparison with a natural nonaromatizable steroid, 5alpha-dihydrotestosterone (DHT). The compound preferentially bound to AR with nanomolar affinity among NRs. When S-40503 was administrated into orchiectomized (ORX) rats for 4 weeks, bone mineral density (BMD) of femur and muscle weight of levator ani were increased as markedly as DHT, but prostate weight was not elevated over the normal at any doses tested. In contrast, DHT administration caused about 1.5-fold increase in prostate weight. The reduced virilizing activity was clearly evident from the result that 4-week treatment of normal rats with S-40503 showed no enlargement of prostate. To confirm the bone anabolic effect, S-40503 was given to ovariectomized (OVX) rats for 2 months. The compound significantly increased the BMD and biomechanical strength of femoral cortical bone, whereas estrogen, anti-bone resorptive hormone, did not. The increase in periosteal mineral apposition rate (MAR) of the femur revealed direct bone formation activity of S-40503. It was unlikely that the osteoanabolic effect of the compound was attribute to the enhancement of muscle mass, because immobilized ORX rats treated with S-40503 showed a marked increase in BMD of tibial cortical bone without any actions on the surrounding muscle tissue. Collectively, our novel compound served as a prototype for SARMs, which had unique tissue selectivity with high potency for bone formation and lower impact upon sex accessory tissues.

  19. Integrated expression profiling and ChIP-seq analyses of the growth inhibition response program of the androgen receptor.

    Directory of Open Access Journals (Sweden)

    Biaoyang Lin

    2009-08-01

    Full Text Available The androgen receptor (AR plays important roles in the development of male phenotype and in different human diseases including prostate cancers. The AR can act either as a promoter or a tumor suppressor depending on cell types. The AR proliferative response program has been well studied, but its prohibitive response program has not yet been thoroughly studied.Previous studies found that PC3 cells expressing the wild-type AR inhibit growth and suppress invasion. We applied expression profiling to identify the response program of PC3 cells expressing the AR (PC3-AR under different growth conditions (i.e. with or without androgens and at different concentration of androgens and then applied the newly developed ChIP-seq technology to identify the AR binding regions in the PC3 cancer genome. A surprising finding was that the comparison of MOCK-transfected PC3 cells with AR-transfected cells identified 3,452 differentially expressed genes (two fold cutoff even without the addition of androgens (i.e. in ethanol control, suggesting that a ligand independent activation or extremely low-level androgen activation of the AR. ChIP-Seq analysis revealed 6,629 AR binding regions in the cancer genome of PC3 cells with an FDR (false discovery rate cut off of 0.05. About 22.4% (638 of 2,849 can be mapped to within 2 kb of the transcription start site (TSS. Three novel AR binding motifs were identified in the AR binding regions of PC3-AR cells, and two of them share a core consensus sequence CGAGCTCTTC, which together mapped to 27.3% of AR binding regions (1,808/6,629. In contrast, only about 2.9% (190/6,629 of AR binding sites contains the canonical AR matrix M00481, M00447 and M00962 (from the Transfac database, which is derived mostly from AR proliferative responsive genes in androgen dependent cells. In addition, we identified four top ranking co-occupancy transcription factors in the AR binding regions, which include TEF1 (Transcriptional enhancer factor

  20. NK cell cytotoxicity mediated by 2B4 and NTB-A is dependent on SAP acting downstream of receptor phosphorylation

    Directory of Open Access Journals (Sweden)

    Stephan eMeinke

    2013-01-01

    Full Text Available 2B4 (CD244 and NK-T-B-antigen (NTB-A, CD352 are activating receptors on human NK cells and belong to the family of SLAM-related receptors. Engagement of these receptors leads to phosphorylation of their cytoplasmic tails and recruitment of the adapter proteins SAP and EAT-2. X-linked lymphoproliferative syndrome (XLP is a severe immunodeficiency that results from mutations in the SAP gene. 2B4 and NTB-A-mediated cytotoxicity are abrogated in XLP NK cells. To elucidate the molecular basis for this defect we analyzed early signaling events in SAP knockdown cells. Similar to XLP NK cells, knockdown of SAP in primary human NK cells leads to a reduction of 2B4 and NTB-A-mediated cytotoxicity. We found that early signaling events such as raft recruitment and receptor phosphorylation are not affected by the absence of SAP, indicating the defect in the absence of SAP is downstream of these events. In addition, knockdown of EAT-2 does not impair 2B4 or NTB-A-mediated cytotoxicity. Surprisingly, EAT-2 recruitment to both receptors is abrogated in the absence of SAP, revealing a novel cooperativity between these adapters.

  1. Receptor-type Protein Tyrosine Phosphatase β Regulates Met Phosphorylation and Function in Head and Neck Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yiru Xu

    2012-11-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC is the sixth most common cancer and has a high rate of mortality. Emerging evidence indicates that hepatocyte growth factor receptor (or Met pathway plays a pivotal role in HNSCC metastasis and resistance to chemotherapy. Met function is dependent on tyrosine phosphorylation that is under direct control by receptor-type protein tyrosine phosphatase β (RPTP-β. We report here that RPTP-β expression is significantly downregulated in HNSCC cells derived from metastatic tumors compared to subject-matched cells from primary tumors. Knockdown of endogenous RPTP-β in HNSCC cells from primary tumor potentiated Met tyrosine phosphorylation, downstream mitogen-activated protein (MAP kinase pathway activation, cell migration, and invasion. Conversely, restoration of RPTP-β expression in cells from matched metastatic tumor decreased Met tyrosine phosphorylation and downstream functions. Furthermore, we observed that six of eight HNSCC tumors had reduced levels of RPTP-β protein in comparison with normal oral tissues. Collectively, the results demonstrate the importance of RPTP-β in tumor biology of HNSCC through direct dephosphorylation of Met and regulation of downstream signal transduction pathways. Reduced RPTP-β levels, with or without Met overexpression, could promote Met activation in HNSCC tumors.

  2. Spinal Tolerance and Dependence: Some Observations on the Role of Spinal N-Methyl-D-Aspartate Receptors and Phosphorylation in the Loss of Opioid Analgesic Responses

    Directory of Open Access Journals (Sweden)

    Tony L Yaksh

    2000-01-01

    Full Text Available The continuous delivery of opiates can lead to a reduction in analgesic effects. In humans, as in other animals, some component of this change in sensitivity seems likely to have a strong pharmacodynamic component. Such loss of effect, deemed to be tolerance in the present article, can be readily demonstrated in animals with repeated bolus and continuous intrathecal infusion of mu and delta opioids and alpha-2 adrenergic agonists. Research has shown that this loss of effect can be diminished by concurrent treatment with N-methyl-D-aspartate (NMDA receptor antagonists and by the suppression of the activity of spinal protein kinase C (PKC. This suggests in part the probable role of PKC-mediated phosphorylation in the right shift in the dose-effect curves observed with continuous opiate or adrenergic exposure. Importantly, this right shift is seen to occur in parallel with an increase in the phosphorylating activity in the dorsal horn and in the expression of several PKC isozymes. The target of this phosphorylation is not certain. Phosphorylation of the NMDA receptor enhances its functionality, while phosphorylation of the opioid receptor or associated channels seems to diminish their activity or to enhance internalization. While the focus is on several specific components, the accumulating data emphasize the biological complexity of these changes in spinal drug reactivity.

  3. Three novel and two known androgen receptor gene mutations ...

    Indian Academy of Sciences (India)

    with androgen insensitivity syndrome in sex-reversed XY female patients. BALACHANDRAN .... Three novel AR gene mutations associated with AIS in XY sex-reversed females. Ta b le. 1 . ( contd. ) ..... disease, 1st edition. Springer Science + ...

  4. Development of Androgen- and Estrogen-Responsive bio-assays, members of a panel of human cell line-based highly selective steroid-responsive bioassays

    NARCIS (Netherlands)

    Sonneveld, E.; Jansen, H.J.

    2004-01-01

    We have established highly sensitive and specific androgen and estrogen reporter cell lines which we have named AR (androgen receptor) and ERα (estrogen receptor alpha) CALUX® (Chemically Activated LUciferase eXpression), respectively. Both bioassays are member of a panel of CALUX reporter cell

  5. The fate of the duplicated androgen receptor in fishes: a late neofunctionalization event?

    Directory of Open Access Journals (Sweden)

    Haendler Bernard

    2008-12-01

    Full Text Available Abstract Background Based on the observation of an increased number of paralogous genes in teleost fishes compared with other vertebrates and on the conserved synteny between duplicated copies, it has been shown that a whole genome duplication (WGD occurred during the evolution of Actinopterygian fish. Comparative phylogenetic dating of this duplication event suggests that it occurred early on, specifically in teleosts. It has been proposed that this event might have facilitated the evolutionary radiation and the phenotypic diversification of the teleost fish, notably by allowing the sub- or neo-functionalization of many duplicated genes. Results In this paper, we studied in a wide range of Actinopterygians the duplication and fate of the androgen receptor (AR, NR3C4, a nuclear receptor known to play a key role in sex-determination in vertebrates. The pattern of AR gene duplication is consistent with an early WGD event: it has been duplicated into two genes AR-A and AR-B after the split of the Acipenseriformes from the lineage leading to teleost fish but before the divergence of Osteoglossiformes. Genomic and syntenic analyses in addition to lack of PCR amplification show that one of the duplicated copies, AR-B, was lost in several basal Clupeocephala such as Cypriniformes (including the model species zebrafish, Siluriformes, Characiformes and Salmoniformes. Interestingly, we also found that, in basal teleost fish (Osteoglossiformes and Anguilliformes, the two copies remain very similar, whereas, specifically in Percomorphs, one of the copies, AR-B, has accumulated substitutions in both the ligand binding domain (LBD and the DNA binding domain (DBD. Conclusion The comparison of the mutations present in these divergent AR-B with those known in human to be implicated in complete, partial or mild androgen insensitivity syndrome suggests that the existence of two distinct AR duplicates may be correlated to specific functional differences that may be

  6. Androgen and retinoic acid interaction in LNCaP cells, effects on cell proliferation and expression of retinoic acid receptors and epidermal growth factor receptor

    International Nuclear Information System (INIS)

    Li, Ming-tang; Richter, Frank; Chang, Chawnshang; Irwin, Robert J; Huang, Hosea FS

    2002-01-01

    Modulation of the expression of retinoic acid receptors (RAR) α and γ in adult rat prostate by testosterone (T) suggests that RAR signaling events might mediate some of the androgen effects on prostate cells. In this study, we examined the interactions between T and retinoic acid (RA) in cell growth of human prostate carcinoma cells, LNCaP, and their relationship with the expression of RAR and epidermal growth factor receptor (EGF-R). Both T and RA, when administered alone, stimulated 3 H-thymidine incorporation in LNCaP cells in a dose-dependent manner; the effect of each agent was reciprocally attenuated by the other agent. Testosterone treatment of LNCaP cells also resulted in dose dependent, biphasic increases in RAR α and γ mRNAs; increases paralleled that of 3 H-thymidine incorporation and were attenuated by the presence of 100 nM RA. These results suggest a link between RAR signaling and the effect of T on LNCaP cell growth. Gel electrophoretic mobility shift assays revealed the presence of putative androgen responsive element (ARE) in the promoter region of RAR α gene, suggesting that a direct AR-DNA interaction might mediate the effects of T on RAR α gene. Furthermore, treatment of LNCaP cells with 20 nM T resulted in an increase in EGF-R. In contrast, EGF-R was suppressed by 100 nM RA that also suppressed the effect of T. Current results demonstrate interactions between T and RA in the expression of RARs and cell growth in LNCaP cells. The presence of putative ARE in the promoter of the RAR α gene suggests that AR-DNA interaction might mediate the effects of T on RAR α gene. The opposite effects of T and RA on the expression of RAR and EGF-R suggest that signal events of these receptors might be involved in the interaction between T and RA in the control of LNCaP cell growth

  7. Androgen and retinoic acid interaction in LNCaP cells, effects on cell proliferation and expression of retinoic acid receptors and epidermal growth factor receptor

    Directory of Open Access Journals (Sweden)

    Irwin Robert J

    2002-06-01

    Full Text Available Abstract Background Modulation of the expression of retinoic acid receptors (RAR α and γ in adult rat prostate by testosterone (T suggests that RAR signaling events might mediate some of the androgen effects on prostate cells. Method In this study, we examined the interactions between T and retinoic acid (RA in cell growth of human prostate carcinoma cells, LNCaP, and their relationship with the expression of RAR and epidermal growth factor receptor (EGF-R. Results Both T and RA, when administered alone, stimulated 3H-thymidine incorporation in LNCaP cells in a dose-dependent manner; the effect of each agent was reciprocally attenuated by the other agent. Testosterone treatment of LNCaP cells also resulted in dose dependent, biphasic increases in RAR α and γ mRNAs; increases paralleled that of 3H-thymidine incorporation and were attenuated by the presence of 100 nM RA. These results suggest a link between RAR signaling and the effect of T on LNCaP cell growth. Gel electrophoretic mobility shift assays revealed the presence of putative androgen responsive element (ARE in the promoter region of RAR α gene, suggesting that a direct AR-DNA interaction might mediate the effects of T on RAR α gene. Furthermore, treatment of LNCaP cells with 20 nM T resulted in an increase in EGF-R. In contrast, EGF-R was suppressed by 100 nM RA that also suppressed the effect of T. Conclusions Current results demonstrate interactions between T and RA in the expression of RARs and cell growth in LNCaP cells. The presence of putative ARE in the promoter of the RAR α gene suggests that AR-DNA interaction might mediate the effects of T on RAR α gene. The opposite effects of T and RA on the expression of RAR and EGF-R suggest that signal events of these receptors might be involved in the interaction between T and RA in the control of LNCaP cell growth.

  8. Androgen receptor immunoreactivity in rat occipital cortex after callosotomy

    Directory of Open Access Journals (Sweden)

    G Lepore

    2009-08-01

    Full Text Available Gonadal steroidogenesis can be influenced by direct neural links between the central nervous system and the gonads. It is known that androgen receptor (AR is expressed in many areas of the rat brain involved in neuroendocrine control of reproduction, such as the cerebral cortex. It has been recently shown that the occipital cortex exerts an inhibitory effect on testicular stereoidogenesis by a pituitary-independent neural mechanism. Moreover, the complete transection of the corpus callosum leads to an increase in testosterone (T secretion of hemigonadectomized rats. The present study was undertaken to analyze the possible corticocortical influences regulating male reproductive activities. Adult male Wistar rats were divided into 4 groups: 1 intact animals as control; 2 rats undergoing sham callosotomy; 3 posterior callosotomy; 4 gonadectomy and posterior callosotomy. Western blot analysis showed no remarkable variations in cortical AR expression in any of the groups except in group I where a significant decrease in AR levels was found. Similarly, both immunocytochemical study and cell count estimation showed a lower AR immunoreactivity in occipital cortex of callosotomized rats than in other groups. In addition, there was no difference in serum T and LH concentration between sham-callosotomized and callosotomized rats. In conclusion, our results show that posterior callosotomy led to a reduction in AR in the right occipital cortex suggesting a putative inhibiting effect of the contralateral cortical area.

  9. Selective Androgen Receptor Modulators (SARMs) as Function Promoting Therapies

    Science.gov (United States)

    Bhasin, Shalender; Jasuja, Ravi

    2010-01-01

    Purpose of review The last decade has witnessed unprecedented discovery effort to develop selective androgen receptor modulators (SARMs) that improve physical function and bone health without adversely affecting the prostate and cardiovascular outcomes. This review describes the historical evolution, the rationale for SARM development, and the mechanisms of testosterone action and SARM selectivity. Recent Findings While steroidal SARMs have been around since the 1940s, a number of nonsteroidal SARMs that do not serve as substrates for CYP19 aromatase or 5α-reductase, act as full agonists in muscle and bone and as partial agonists in prostate are in development. The differing interactions of steroidal and nonsteroidal compounds with AR contribute to their unique pharmacologic actions. Ligand binding induces specific conformational changes in the ligand binding domain, which could modulate surface topology and protein-protein interactions between AR and coregulators, resulting in tissue-specific gene regulation. Preclinical studies have demonstrated the ability of SARMs to increase muscle and bone mass in preclinical rodent models with varying degree of prostate sparing. Phase I trials of SARMs in humans have reported modest increments in fat-free mass. Summary SARMs hold promise as a new class of function promoting anabolic therapies for a number of clinical indications, including functional limitations associated with aging and chronic disease, frailty, cancer cachexia, and osteoporosis. PMID:19357508

  10. REST mediates androgen receptor actions on gene repression and predicts early recurrence of prostate cancer

    DEFF Research Database (Denmark)

    Svensson, Charlotte; Ceder, Jens; Iglesias Gato, Diego

    2014-01-01

    The androgen receptor (AR) is a key regulator of prostate tumorgenesis through actions that are not fully understood. We identified the repressor element (RE)-1 silencing transcription factor (REST) as a mediator of AR actions on gene repression. Chromatin immunoprecipitation showed that AR binds...... in cell cycle progression, including Aurora Kinase A, that has previously been implicated in the growth of NE-like castration-resistant tumors. The analysis of prostate cancer tissue microarrays revealed that tumors with reduced expression of REST have higher probability of early recurrence, independently...... of their Gleason score. The demonstration that REST modulates AR actions in prostate epithelia and that REST expression is negatively correlated with disease recurrence after prostatectomy, invite a deeper characterization of its role in prostate carcinogenesis....

  11. 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.

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