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Sample records for pten develops mammary

  1. PTEN Loss in E-Cadherin-Deficient Mouse Mammary Epithelial Cells Rescues Apoptosis and Results in Development of Classical Invasive Lobular Carcinoma

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    Mirjam C. Boelens

    2016-08-01

    Full Text Available Invasive lobular carcinoma (ILC is an aggressive breast cancer subtype with poor response to chemotherapy. Besides loss of E-cadherin, a hallmark of ILC, genetic inactivation of PTEN is frequently observed in patients. Through concomitant Cre-mediated inactivation of E-cadherin and PTEN in mammary epithelium, we generated a mouse model of classical ILC (CLC, the main histological ILC subtype. While loss of E-cadherin induced cell dissemination and apoptosis, additional PTEN inactivation promoted cell survival and rapid formation of invasive mammary tumors that recapitulate the histological and molecular features, estrogen receptor (ER status, growth kinetics, metastatic behavior, and tumor microenvironment of human CLC. Combined inactivation of E-cadherin and PTEN is sufficient to cause CLC development. These CLCs showed significant tumor regression upon BEZ235-mediated inhibition of PI3K signaling. In summary, this mouse model provides important insights into CLC development and suggests inhibition of phosphatidylinositol 3-kinase (PI3K signaling as a potential therapeutic strategy for targeting CLC.

  2. Regulation of mammary stem/progenitor cells by PTEN/Akt/beta-catenin signaling.

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    Hasan Korkaya

    2009-06-01

    Full Text Available Recent evidence suggests that many malignancies, including breast cancer, are driven by a cellular subcomponent that displays stem cell-like properties. The protein phosphatase and tensin homolog (PTEN is inactivated in a wide range of human cancers, an alteration that is associated with a poor prognosis. Because PTEN has been reported to play a role in the maintenance of embryonic and tissue-specific stem cells, we investigated the role of the PTEN/Akt pathway in the regulation of normal and malignant mammary stem/progenitor cell populations. We demonstrate that activation of this pathway, via PTEN knockdown, enriches for normal and malignant human mammary stem/progenitor cells in vitro and in vivo. Knockdown of PTEN in normal human mammary epithelial cells enriches for the stem/progenitor cell compartment, generating atypical hyperplastic lesions in humanized NOD/SCID mice. Akt-driven stem/progenitor cell enrichment is mediated by activation of the Wnt/beta-catenin pathway through the phosphorylation of GSK3-beta. In contrast to chemotherapy, the Akt inhibitor perifosine is able to target the tumorigenic cell population in breast tumor xenografts. These studies demonstrate an important role for the PTEN/PI3-K/Akt/beta-catenin pathway in the regulation of normal and malignant stem/progenitor cell populations and suggest that agents that inhibit this pathway are able to effectively target tumorigenic breast cancer cells.

  3. Canine Mammary Tumours Are Affected by Frequent Copy Number Aberrations, including Amplification of MYC and Loss of PTEN.

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    Kaja S Borge

    Full Text Available Copy number aberrations frequently occur during the development of many cancers. Such events affect dosage of involved genes and may cause further genomic instability and progression of cancer. In this survey, canine SNP microarrays were used to study 117 canine mammary tumours from 69 dogs.We found a high occurrence of copy number aberrations in canine mammary tumours, losses being more frequent than gains. Increased frequency of aberrations and loss of heterozygosity were positively correlated with increased malignancy in terms of histopathological diagnosis. One of the most highly recurrently amplified regions harbored the MYC gene. PTEN was located to a frequently lost region and also homozygously deleted in five tumours. Thus, deregulation of these genes due to copy number aberrations appears to be an important event in canine mammary tumour development. Other potential contributors to canine mammary tumour pathogenesis are COL9A3, INPP5A, CYP2E1 and RB1. The present study also shows that a more detailed analysis of chromosomal aberrations associated with histopathological parameters may aid in identifying specific genes associated with canine mammary tumour progression.The high frequency of copy number aberrations is a prominent feature of canine mammary tumours as seen in other canine and human cancers. Our findings share several features with corresponding studies in human breast tumours and strengthen the dog as a suitable model organism for this disease.

  4. Pten Regulates Epithelial Cytodifferentiation during Prostate Development

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    Lokody, Isabel B; Francis, Jeffrey C; Gardiner, Jennifer R;

    2015-01-01

    Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic...... deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses...... that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study...

  5. Pten Regulates Epithelial Cytodifferentiation during Prostate Development.

    Directory of Open Access Journals (Sweden)

    Isabel B Lokody

    Full Text Available Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses, abnormal luminal cells fill the ductal lumens together with augmented epithelial proliferation. This phenotype resembles the hyperplasia seen in postnatal Pten deletion models that develop neoplasia at later stages. Consistent with this, gene expression analysis showed a number of genes affected that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study provides novel insight into the role of Pten in prostate development as part of the process of coordinating the differentiation and proliferation of cell types in time and space to form a functional organ.

  6. Pten Regulates Epithelial Cytodifferentiation during Prostate Development

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    Lokody, Isabel B.; Francis, Jeffrey C.; Gardiner, Jennifer R.; Erler, Janine T.; Swain, Amanda

    2015-01-01

    Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses, abnormal luminal cells fill the ductal lumens together with augmented epithelial proliferation. This phenotype resembles the hyperplasia seen in postnatal Pten deletion models that develop neoplasia at later stages. Consistent with this, gene expression analysis showed a number of genes affected that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study provides novel insight into the role of Pten in prostate development as part of the process of coordinating the differentiation and proliferation of cell types in time and space to form a functional organ. PMID:26076167

  7. Mammary gland development.

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    Macias, Hector; Hinck, Lindsay

    2012-01-01

    The mammary gland develops through several distinct stages. The first transpires in the embryo as the ectoderm forms a mammary line that resolves into placodes. Regulated by epithelial–mesenchymal interactions, the placodes descend into the underlying mesenchyme and produce the rudimentary ductal structure of the gland present at birth. Subsequent stages of development—pubertal growth, pregnancy, lactation, and involution—occur postnatally under the regulation of hormones. Puberty initiates branching morphogenesis, which requires growth hormone (GH) and estrogen, as well as insulin-like growth factor 1 (IGF1), to create a ductal tree that fills the fat pad. Upon pregnancy, the combined actions of progesterone and prolactin generate alveoli, which secrete milk during lactation. Lack of demand for milk at weaning initiates the process of involution whereby the gland is remodeled back to its prepregnancy state. These processes require numerous signaling pathways that have distinct regulatory functions at different stages of gland development. Signaling pathways also regulate a specialized subpopulation of mammary stem cells that fuel the dramatic changes in the gland occurring with each pregnancy. Our knowledge of mammary gland development and mammary stem cell biology has significantly contributed to our understanding of breast cancer and has advanced the discovery of therapies to treat this disease.

  8. Interaction of E-cadherin and PTEN regulates morphogenesis and growth arrest in human mammary epithelial cells

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    Fournier, Marcia V.; Fata, Jimmie E.; Martin, Katherine J.; Yaswen, Paul; Bissell, Mina J.

    2009-06-03

    PTEN is a dual function phosphatase with tumor suppressor function compromised in a wide spectrum of cancers. Because tissue polarity and architecture are crucial modulators of normal and malignant behavior, we postulated that PTEN may play a role in maintenance of tissue integrity. We used two non-malignant human mammary epithelial cell lines (HMECs) that form polarized, growth-arrested structures (acini) when cultured in 3-dimensional laminin-rich extracellular matrix gels (3D lrECM). As acini begin to form, PTEN accumulates in both the cytoplasm, and at cell-cell contacts where it colocalizes with E-cadherin/{beta}-catenin complex. Reduction of PTEN levels by shRNA in lrECM prevents formation of organized breast acini and disrupts growth arrest. Importantly, disruption of acinar polarity and cell-cell contact by E-cadherin function-blocking antibodies reduces endogenous PTEN protein levels and inhibits its accumulation at cell-cell contacts. Conversely, in SKBR3 breast cancer cells lacking endogenous E-cadherin expression, exogenous introduction of E-cadherin gene causes induction of PTEN expression and its accumulation at sites of cell interactions. These studies provide evidence that E-cadherin regulates both the PTEN protein levels and its recruitment to cell-cell junctions in 3D lrECM indicating a dynamic reciprocity between architectural integrity and the levels and localization of PTEN. This interaction thus appears to be a critical integrator of proliferative and morphogenetic signaling in breast epithelial cells.

  9. PTEN and p53 cross-regulation induced by soy isoflavone genistein promotes mammary epithelial cell cycle arrest and lobuloalveolar differentiation.

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    Rahal, Omar M; Simmen, Rosalia C M

    2010-08-01

    The tumor suppressors phosphatase and tensin homologue deleted on chromosome ten (PTEN) and p53 are closely related to the pathogenesis of breast cancer, yet pathway-specific mechanisms underlying their participation in mediating the protective actions of dietary bioactive components on breast cancer risk are poorly understood. We recently showed that dietary exposure to the soy isoflavone genistein (GEN) induced PTEN expression in mammary epithelial cells in vivo and in vitro, consistent with the breast cancer preventive effects of soy food consumption. Here, we evaluated PTEN and p53 functional interactions in the nuclear compartment of mammary epithelial cells as a mechanism for mammary tumor protection by GEN. Using the non-tumorigenic human mammary epithelial cells MCF10-A, we demonstrate that GEN increased PTEN expression and nuclear localization. We show that increased nuclear PTEN levels initiated an autoregulatory loop involving PTEN-dependent increases in p53 nuclear localization, PTEN-p53 physical association, PTEN-p53 co-recruitment to the PTEN promoter region and p53 transactivation of PTEN promoter activity. The PTEN-p53 cross talk induced by GEN resulted in increased cell cycle arrest; decreased pro-proliferative cyclin D1 and pleiotrophin gene expression and the early formation of mammary acini, indicative of GEN promotion of lobuloalveolar differentiation. Our findings provide support to GEN-induced PTEN as both a target and regulator of p53 action and offer a mechanistic basis for PTEN pathway activation to underlie the antitumor properties of dietary factors, with important implications for reducing breast cancer risk.

  10. Alterations of EGFR, p53 and PTEN that mimic changes found in basal-like breast cancer promote transformation of human mammary epithelial cells.

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    Pires, Maira M; Hopkins, Benjamin D; Saal, Lao H; Parsons, Ramon E

    2013-03-01

    Breast cancer can be classified into different molecular subtypes with varying clinical and pathological characteristics. The basal-like breast cancer subtype represents one of the most aggressive and lethal types of breast cancer, and due to poor mechanistic understanding, it lacks targeted therapy. Many basal-like breast cancer patient samples display alterations of established drivers of cancer development, including elevated expression of EGFR, p53 inactivating mutations and loss of expression of the tumor suppressor PTEN; however, their contribution to human basal-like breast cancer pathogenesis remains ill-defined. Using non-transformed human mammary epithelial cells, we set out to determine whether altering EGFR, p53 and PTEN in different combinations could contribute to basal-like breast cancer progression through transformation of cells. Altering PTEN in combination with either p53 or EGFR in contrast to any of the single alterations caused increased growth of transformed colonies in soft agar. Concomitantly modifying all three genes led to the highest rate of cellular proliferation and the greatest degree of anchorage-independent colony formation. Results from our effort to engineer a model of BBC expressing alterations of EGFR, p53 and PTEN suggest that these changes are cooperative and likely play a causal role in basal-like breast cancer pathogenesis. Consideration should be given to targeting EGFR and restoring p53 and PTEN signaling simultaneously as a strategy for treatment of this subtype of breast cancer.

  11. Pten Regulates Lactation in Dairy Cow Mammary Epithelial Cells%Pten基因对奶牛乳腺上皮细胞泌乳的调节功能

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    王卓然; 王春梅; 王杰; 李庆章; 高学军

    2016-01-01

    Pten基因参与调节奶牛乳腺上皮细胞泌乳的过程,负向调节细胞的活力、增殖能力和细胞周期,并能抑制奶牛乳腺上皮细胞分泌?-酪蛋白、甘油三酯和乳糖;这种调节作用是通过Pten基因靶向调节PI3K-AKT信号通路,进而调节其他泌乳相关信号通路基因的表达而实现的;同时发现Pten基因的表达受催乳素的负调节,但葡萄糖对Pten基因的表达水平无显著影响。%In the aim of detectting the role of Pten gene in the mammary gland of dairy cow, dairy cows mammary epithelial cells (DCMECs) in mid-lactation period were used as models to investigate the relationship of Pten expression and mammary glands development and lactation, which provides basic data for the study of ruminant mammary gland development and lactation mechanisms, and the theoretical support for milk production and milk quality of the artificial regulation at the same time. In this research, Holstein dairy cows were used as experimental animals, applying to qRT-PCR, Western blotting, and immunofluorescence triple staining technology, Pten mRNA and protein expression at different development stages and various milk qualities of dairy cows mammary gland tissue were detected. Furthermore, DCMECs as research objects in vitro were used to study the function of Pten gene. Recombinant plasmid pGCMV-Pten-IRES-EGFP was constructed and transient transfected into cells to prosue the Pten gene overexpression experiment. Meanwhile, RNAi method was used to transfect Pten siRNA in the Pten gene inhibition experiment. We determined concentrations of β-casein, triglyceride, and lactose following Pten gene overexpression and inhibition by specific kits. To determine whether Pten gene affected DCMEC viability and proliferation, cells were analyzed by CASY-TT and flow cytometry. Genes involved in lactation-related signaling pathways were detected by qRT-PCR and Western blotting. After prolactin and glucose were added to the

  12. PTEN and p53 cross-regulation induced by soy isoflavone genistein promotes mammary epithelial cell cycle arrest and lobuloalveolar differentiation

    OpenAIRE

    2010-01-01

    The tumor suppressors phosphatase and tensin homologue deleted on chromosome ten (PTEN) and p53 are closely related to the pathogenesis of breast cancer, yet pathway-specific mechanisms underlying their participation in mediating the protective actions of dietary bioactive components on breast cancer risk are poorly understood. We recently showed that dietary exposure to the soy isoflavone genistein (GEN) induced PTEN expression in mammary epithelial cells in vivo and in vitro, consistent wit...

  13. Subtle variations in Pten dose determine cancer susceptibility.

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    Alimonti, Andrea; Carracedo, Arkaitz; Clohessy, John G; Trotman, Lloyd C; Nardella, Caterina; Egia, Ainara; Salmena, Leonardo; Sampieri, Katia; Haveman, William J; Brogi, Edi; Richardson, Andrea L; Zhang, Jiangwen; Pandolfi, Pier Paolo

    2010-05-01

    Cancer susceptibility has been attributed to at least one heterozygous genetic alteration in a tumor suppressor gene (TSG). It has been hypothesized that subtle variations in TSG expression can promote cancer development. However, this hypothesis has not yet been definitively supported in vivo. Pten is a TSG frequently lost in human cancer and mutated in inherited cancer-predisposition syndromes. Here we analyze Pten hypermorphic mice (Pten(hy/+)), expressing 80% normal levels of Pten. Pten(hy/+) mice develop a spectrum of tumors, with breast tumors occurring at the highest penetrance. All breast tumors analyzed here retained two intact copies of Pten and maintained Pten levels above heterozygosity. Notably, subtle downregulation of Pten altered the steady-state biology of the mammary tissues and the expression profiles of genes involved in cancer cell proliferation. We present an alterative working model for cancer development in which subtle reductions in the dose of TSGs predispose to tumorigenesis in a tissue-specific manner.

  14. Combined deletion of Pten and p53 in mammary epithelium accelerates triple-negative breast cancer with dependency on eEF2K.

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    Liu, Jeff C; Voisin, Veronique; Wang, Sharon; Wang, Dong-Yu; Jones, Robert A; Datti, Alessandro; Uehling, David; Al-awar, Rima; Egan, Sean E; Bader, Gary D; Tsao, Ming; Mak, Tak W; Zacksenhaus, Eldad

    2014-12-01

    The tumor suppressors Pten and p53 are frequently lost in breast cancer, yet the consequences of their combined inactivation are poorly understood. Here, we show that mammary-specific deletion of Pten via WAP-Cre, which targets alveolar progenitors, induced tumors with shortened latency compared to those induced by MMTV-Cre, which targets basal/luminal progenitors. Combined Pten-p53 mutations accelerated formation of claudin-low, triple-negative-like breast cancer (TNBC) that exhibited hyper-activated AKT signaling and more mesenchymal features relative to Pten or p53 single-mutant tumors. Twenty-four genes that were significantly and differentially expressed between WAP-Cre:Pten/p53 and MMTV-Cre:Pten/p53 tumors predicted poor survival for claudin-low patients. Kinome screens identified eukaryotic elongation factor-2 kinase (eEF2K) inhibitors as more potent than PI3K/AKT/mTOR inhibitors on both mouse and human Pten/p53-deficient TNBC cells. Sensitivity to eEF2K inhibition correlated with AKT pathway activity. eEF2K monotherapy suppressed growth of Pten/p53-deficient TNBC xenografts in vivo and cooperated with doxorubicin to efficiently kill tumor cells in vitro. Our results identify a prognostic signature for claudin-low patients and provide a rationale for using eEF2K inhibitors for treatment of TNBC with elevated AKT signaling.

  15. In MMTV-Her-2/neu transgenic mammary tumors the absence of caveolin-1-/- alters PTEN and NHERF1 but not β-catenin expression.

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    Cuello-Carrión, F Darío; Cayado-Gutiérrez, Niubys; Natoli, Anthony L; Restall, Christina; Anderson, Robin L; Nadin, Silvina; Alvarez-Olmedo, Daiana; Castro, Gisela N; Gago, Francisco E; Fanelli, Mariel A; Ciocca, Daniel R

    2013-09-01

    In a recent study, we have shown that in mammary tumors from mice lacking the Cav-1 gene, there are alterations in specific heat shock proteins as well as in tumor development. With this in mind, we have now investigated other proteins in the same mammary mouse tumor model (Her-2/neu expressing mammary tumors from Cav-1 wild type and Cav-1 null mice), to further comprehend the complex tumor-stroma mechanisms involved in regulating stress responses during tumor development. In this tumor model the cancer cells always lacked of Cav-1, so the KO influenced the Cav-1 in the stroma. By immunohistochemistry, we have found a striking co-expression of β-catenin and Her-2/neu in the tumor cells. The absence of Cav-1 in the tumor stroma had no effect on expression or localization of β-catenin and Her-2/neu. Both proteins appeared co-localized at the cell surface during tumor development and progression. Since Her-2/neu activation induces MTA1, we next evaluated MTA1 in the mouse tumors. Although this protein was found in numerous nuclei, the absence of Cav-1 did not alter its expression level. In contrast, significantly more PTEN protein was noted in the tumors lacking Cav-1 in the stroma, with the protein localized mainly in the nuclei. P-Akt levels were relatively low in tumors from both Cav-1 WT and Cav-1 KO mice. There was also an increase in nuclear NHERF1 expression levels in the tumors arising from Cav-1 KO mice. The data obtained in the MMTV-neu model are consistent with a role for Cav-1 in adjacent breast cancer stromal cells in modulating the expression and localization of important proteins implicated in tumor cell behavior.

  16. The soybean peptide lunasin promotes apoptosis of mammary epithelial cells via induction of tumor suppressor PTEN: similarities and distinct actions from soy isoflavone genistein.

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    Pabona, John Mark P; Dave, Bhuvanesh; Su, Ying; Montales, Maria Theresa E; de Lumen, Ben O; de Mejia, Elvira G; Rahal, Omar M; Simmen, Rosalia C M

    2013-01-01

    Breast cancer is the leading cause of cancer deaths in women. Diet and lifestyle are major contributing factors to increased breast cancer risk. While mechanisms underlying dietary protection of mammary tumor formation are increasingly elucidated, there remains a dearth of knowledge on the nature and precise actions of specific bioactive components present in foods with purported health effects. The 43-amino acid peptide lunasin (LUN) is found in soybeans, is bioavailable similar to the isoflavone genistein (GEN), and thus may mediate the beneficial effects of soy food consumption. Here, we evaluated whether LUN displays common and distinct actions from those of GEN in non-malignant (mouse HC11) and malignant (human MCF-7) mammary epithelial cells. In MCF-7 cells, LUN up-regulated tumor suppressor phosphatase and tensin homolog deleted in chromosome ten (PTEN) promoter activity, increased PTEN transcript and protein levels and enhanced nuclear PTEN localization, similar to that shown for GEN in mammary epithelial cells. LUN-induced cellular apoptosis, akin to GEN, was mediated by PTEN, but unlike that for GEN, was p53-independent. LUN promoted E-cadherin and β-catenin non-nuclear localization similar to GEN, but unlike GEN, did not influence the proliferative effects of oncogene Wnt1 on HC11 cells. Further, LUN did not recapitulate GEN inhibitory effects on expansion of the cancer stem-like/progenitor population in MCF-7 cells. Results suggest the concerted actions of GEN and LUN on cellular apoptosis for potential mammary tumor preventive effects and highlight whole food consumption rather than intake of specific dietary supplements with limited biological effects for greater health benefits.

  17. Adiponectin haploinsufficiency promotes mammary tumor development in MMTV-PyVT mice by modulation of phosphatase and tensin homolog activities.

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    Janice B B Lam

    Full Text Available BACKGROUND: Adiponectin is an adipokine possessing beneficial effects on obesity-related medical complications. A negative association of adiponectin levels with breast cancer development has been demonstrated. However, the precise role of adiponectin deficiency in mammary carcinogenesis remains elusive. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, MMTV-polyomavirus middle T antigen (MMTV-PyVT transgenic mice with reduced adiponectin expressions were established and the stromal effects of adiponectin haploinsufficiency on mammary tumor development evaluated. In mice from both FVB/N and C57BL/6J backgrounds, insufficient adiponectin production promoted mammary tumor onset and development. A distinctive basal-like subtype of tumors, with a more aggressive phenotype, was derived from adiponectin haplodeficient MMTV-PyVT mice. Comparing with those from control MMTV-PyVT mice, the isolated mammary tumor cells showed enhanced tumor progression in re-implanted nude mice, accelerated proliferation in primary cultures, and hyperactivated phosphatidylinositol-3-kinase (PI3K/Akt/beta-catenin signaling, which at least partly attributed to the decreased phosphatase and tensin homolog (PTEN activities. Further analysis revealed that PTEN was inactivated by a redox-regulated mechanism. Increased association of PTEN-thioredoxin complexes was detected in tumors derived from mice with reduced adiponectin levels. The activities of thioredoxin (Trx1 and thioredoxin reductase (TrxR1 were significantly elevated, whereas treatment with either curcumin, an irreversible inhibitor of TrxR1, or adiponectin largely attenuated their activities and resulted in the re-activation of PTEN in these tumor cells. Moreover, adiponectin could inhibit TrxR1 promoter-mediated transcription and restore the mRNA expressions of TrxR1. CONCLUSION: Adiponectin haploinsufficiency facilitated mammary tumorigenesis by down-regulation of PTEN activity and activation of PI3K

  18. Dietary genistein stimulates mammary development in gilts

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    The possible role of the phytoestrogen, genistein, on prepubertal development of mammary glands, hormonal status and bone resorption was investigated in gilts. Forty-five gilts were fed a control diet containing soya (CTLS, n = 15), a control diet without soya (CTL0, n = 15) or the CTLS diet supplem...

  19. Distinct stem cells contribute to mammary gland development and maintenance.

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    Van Keymeulen, Alexandra; Rocha, Ana Sofia; Ousset, Marielle; Beck, Benjamin; Bouvencourt, Gaëlle; Rock, Jason; Sharma, Neha; Dekoninck, Sophie; Blanpain, Cédric

    2011-10-09

    The mammary epithelium is composed of several cell lineages including luminal, alveolar and myoepithelial cells. Transplantation studies have suggested that the mammary epithelium is maintained by the presence of multipotent mammary stem cells. To define the cellular hierarchy of the mammary gland during physiological conditions, we performed genetic lineage-tracing experiments and clonal analysis of the mouse mammary gland during development, adulthood and pregnancy. We found that in postnatal unperturbed mammary gland, both luminal and myoepithelial lineages contain long-lived unipotent stem cells that display extensive renewing capacities, as demonstrated by their ability to clonally expand during morphogenesis and adult life as well as undergo massive expansion during several cycles of pregnancy. The demonstration that the mammary gland contains different types of long-lived stem cells has profound implications for our understanding of mammary gland physiology and will be instrumental in unravelling the cells at the origin of breast cancers.

  20. Parathyroid hormone-related protein specifies the mammary mesenchyme and regulates embryonic mammary development.

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    Hiremath, Minoti; Wysolmerski, John

    2013-06-01

    Parathyroid Hormone related Protein (PTHrP) is a critical regulator of mammary gland morphogenesis in the mouse embryo. Loss of PTHrP, or its receptor, PTHR1, results in arrested mammary buds at day 15 of embryonic development (E15). In contrast, overexpression of PTHrP converts the ventral epidermis into hairless nipple skin. PTHrP signaling appears to be critical for mammary mesenchyme specification, which in turn maintains mammary epithelial identity, directs bud outgrowth, disrupts the male mammary rudiment and specifies the formation of the nipple. In the embryonic mammary bud, PTHrP exerts its effects on morphogenesis, in part, through epithelial-stromal crosstalk mediated by Wnt and BMP signaling. Recently, PTHLH has been identified as a strong candidate for a novel breast cancer susceptibility locus, although PTHrP's role in breast cancer has not been clearly defined. The effects of PTHrP on the growth of the embryonic mammary rudiment and its invasion into the dermis may, in turn, have connections to the role of PTHrP in breast cancer.

  1. Subtle variations in Pten dose determine cancer susceptibility

    Science.gov (United States)

    Alimonti, Andrea; Carracedo, Arkaitz; Clohessy, John G; Trotman, Lloyd C; Nardella, Caterina; Egia, Ainara; Salmena, Leonardo; Sampieri, Katia; Haveman, William J; Brogi, Edi; Richardson, Andrea L; Zhang, Jiangwen; Pandolfi, Pier Paolo

    2010-01-01

    Cancer susceptibility has been attributed to at least one heterozygous genetic alteration in a tumor suppressor gene (TSG)1. It has been hypothesized that subtle variations in TSG expression can promote cancer development2,3. However, this hypothesis has not yet been definitively supported in vivo. PTEN is a TSG frequently lost in human cancer and mutated in inherited cancer-predisposition syndromes4. Here, we analyze Pten hypermorphic mice (Ptenhy/+), expressing 80% normal levels of Pten. Ptenhy/+ mice develop a spectrum of tumors, with breast tumors occurring at the highest penetrance. All breast tumors analyzed here retained two intact copies of Pten and maintained Pten levels above heterozygosis. Notably, subtle downregulation of Pten altered the steady-state biology of the mammary tissues and the expression profiles of genes involved in cancer cell proliferation. We present an alterative working model for cancer development in which subtle reductions in the dose of TSGs predispose to tumorigenesis in a tissue-specific manner. PMID:20400965

  2. Mammary Development and Breast Cancer: A Wnt Perspective

    OpenAIRE

    Qing Cissy Yu; Verheyen, Esther M.; Yi Arial Zeng

    2016-01-01

    The Wnt pathway has emerged as a key signaling cascade participating in mammary organogenesis and breast oncogenesis. In this review, we will summarize the current knowledge of how the pathway regulates stem cells and normal development of the mammary gland, and discuss how its various components contribute to breast carcinoma pathology.

  3. Mammary development and breast cancer: the role of stem cells.

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    Ercan, C; van Diest, P J; Vooijs, M

    2011-06-01

    The mammary gland is a highly regenerative organ that can undergo multiple cycles of proliferation, lactation and involution, a process controlled by stem cells. The last decade much progress has been made in the identification of signaling pathways that function in these stem cells to control self-renewal, lineage commitment and epithelial differentiation in the normal mammary gland. The same signaling pathways that control physiological mammary development and homeostasis are also often found deregulated in breast cancer. Here we provide an overview on the functional and molecular identification of mammary stem cells in the context of both normal breast development and breast cancer. We discuss the contribution of some key signaling pathways with an emphasis on Notch receptor signaling, a cell fate determination pathway often deregulated in breast cancer. A further understanding of the biological roles of the Notch pathway in mammary stem cell behavior and carcinogenesis might be relevant for the development of future therapies.

  4. PTEN at 18: Still Growing.

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    Gorbenko, Olena; Stambolic, Vuk

    2016-01-01

    Discovered in 1997, PTEN remains one of the most studied tumor suppressors. In this issue of Methods in Molecular Biology, we assembled a series of papers describing various clinical and experimental approaches to studying PTEN function. Due to its broad expression, regulated subcellular localization, and intriguing phosphatase activity, methodologies aimed at PTEN study have often been developed in the context of mutations affecting various aspects of its regulation, found in patients burdened with PTEN loss-driven tumors. PTEN's extensive posttranslational modifications and dynamic localization pose unique challenges for studying PTEN features in isolation and necessitate considerable development of experimental systems to enable controlled characterization. Nevertheless, ongoing efforts towards the development of PTEN knockout and knock-in animals and cell lines, antibodies, and enzymatic assays have facilitated a huge body of work, which continues to unravel the fascinating biology of PTEN.

  5. PTEN/PIK3CA genes are frequently mutated in spontaneous and medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumours of tree shrews.

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    Xia, Hou-Jun; He, Bao-Li; Wang, Chun-Yan; Zhang, Hai-Lin; Ge, Guang-Zhe; Zhang, Yuan-Xu; Lv, Long-Bao; Jiao, Jian-Lin; Chen, Ceshi

    2014-12-01

    Tree shrew has increasingly become an attractive experimental animal model for human diseases, particularly for breast cancer due to spontaneous breast tumours and their close relationship to primates and by extension to humans. However, neither normal mammary glands nor breast tumours have been well characterised in the Chinese tree shrew (Tupaia belangeri chinensis). In this study, normal mammary glands from four different developmental stages and 18 spontaneous breast tumours were analysed. Haematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) showed that normal mammary gland morphology and structures of tree shrews were quite similar to those found in humans. Spontaneous breast tumours of tree shrews were identified as being intraductal papilloma, papillary carcinoma, and invasive ductal carcinoma with or without lung metastasis. To further analyse breast cancer tumours among tree shrews, 40 3-4 month-old female tree shrews were orally administrated 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) or peanut oil thrice, and then, 15 of these DMBA administrated tree shrews were implanted with medroxyprogesterone acetate (MPA) pellets. DMBA was shown to induce breast tumours (12%) while the addition of MPA increased the tumour incidence (50%). Of these, three induced breast tumours were intraductal papillary carcinomas and one was invasive ductal carcinoma (IDC). The PTEN/PIK3CA (phosphatase and tensin homologue/phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), but not TP53 and GATA3, genes are frequently mutated in breast tumours, and the PTEN/PIK3CA gene mutation status correlated with the expression of pAKT in tree shrew breast tumours. These results suggest that tree shrews may be a promising animal model for a subset of human breast cancers with PTEN/PIK3CA gene mutations.

  6. Luminal progenitors restrict their lineage potential during mammary gland development.

    Science.gov (United States)

    Rodilla, Veronica; Dasti, Alessandro; Huyghe, Mathilde; Lafkas, Daniel; Laurent, Cécile; Reyal, Fabien; Fre, Silvia

    2015-02-01

    The hierarchical relationships between stem cells and progenitors that guide mammary gland morphogenesis are still poorly defined. While multipotent basal stem cells have been found within the myoepithelial compartment, the in vivo lineage potential of luminal progenitors is unclear. Here we used the expression of the Notch1 receptor, previously implicated in mammary gland development and tumorigenesis, to elucidate the hierarchical organization of mammary stem/progenitor cells by lineage tracing. We found that Notch1 expression identifies multipotent stem cells in the embryonic mammary bud, which progressively restrict their lineage potential during mammary ductal morphogenesis to exclusively generate an ERαneg luminal lineage postnatally. Importantly, our results show that Notch1-labelled cells represent the alveolar progenitors that expand during pregnancy and survive multiple successive involutions. This study reveals that postnatal luminal epithelial cells derive from distinct self-sustained lineages that may represent the cells of origin of different breast cancer subtypes.

  7. Luminal progenitors restrict their lineage potential during mammary gland development.

    Directory of Open Access Journals (Sweden)

    Veronica Rodilla

    2015-02-01

    Full Text Available The hierarchical relationships between stem cells and progenitors that guide mammary gland morphogenesis are still poorly defined. While multipotent basal stem cells have been found within the myoepithelial compartment, the in vivo lineage potential of luminal progenitors is unclear. Here we used the expression of the Notch1 receptor, previously implicated in mammary gland development and tumorigenesis, to elucidate the hierarchical organization of mammary stem/progenitor cells by lineage tracing. We found that Notch1 expression identifies multipotent stem cells in the embryonic mammary bud, which progressively restrict their lineage potential during mammary ductal morphogenesis to exclusively generate an ERαneg luminal lineage postnatally. Importantly, our results show that Notch1-labelled cells represent the alveolar progenitors that expand during pregnancy and survive multiple successive involutions. This study reveals that postnatal luminal epithelial cells derive from distinct self-sustained lineages that may represent the cells of origin of different breast cancer subtypes.

  8. Development of mammary glands of fat sheep submitted to restricted feeding during late pregnancy

    DEFF Research Database (Denmark)

    Nørgaard, J V; Nielsen, M O; Theil, P K;

    2008-01-01

    Mammary gland development in sheep occurs mainly during puberty and pregnancy. We have investigated the effects of a late gestation feed restriction on mammary gland development in sheep.......Mammary gland development in sheep occurs mainly during puberty and pregnancy. We have investigated the effects of a late gestation feed restriction on mammary gland development in sheep....

  9. Hippo pathway in mammary gland development and breast cancer.

    Science.gov (United States)

    Shi, Peiguo; Feng, Jing; Chen, Ceshi

    2015-01-01

    Accumulated evidence suggests that the Hippo signaling pathway plays crucial roles in mammary gland development and breast cancer. Key components of the Hippo pathway regulate breast epithelial cell proliferation, migration, invasion, and stemness. Additionally, the Hippo pathway regulates breast tumor growth, metastasis, and drug resistance. It is expected that the Hippo pathway will provide novel therapeutic targets for breast cancer. This review will discuss and summarize the roles of several core components of the Hippo pathway in mammary gland development and breast cancer.

  10. Notch in mammary gland development and breast cancer.

    Science.gov (United States)

    Politi, Katerina; Feirt, Nikki; Kitajewski, Jan

    2004-10-01

    Notch signaling has been implicated in many processes including cell fate determination and oncogenesis. In mice, the Notch1 and Notch4 genes are both targets for insertion and rearrangement by the mouse mammary tumor virus and these mutations promote epithelial mammary tumorigenesis. Moreover, expression of a constitutively active form of Notch4 in mammary epithelial cells inhibits epithelial differentiation and leads to tumor formation in this organ. These data implicate the Notch pathway in breast tumorigenesis and provide the foundation for future experiments that will aid in our understanding of the role of Notch in human breast cancer development. Here, we review studies of mammary tumorigenesis induced by Notch in mouse and in vitro culture models providing evidence that Notch activation is a causal factor in human breast cancer.

  11. Alcohol exposure in utero leads to enhanced prepubertal mammary development and alterations in mammary IGF and estradiol systems.

    Science.gov (United States)

    Polanco, Tiffany A; Crismale-Gann, Catina; Cohick, Wendie S

    2011-08-01

    Exposure to alcohol during fetal development increases susceptibility to mammary cancer in adult rats. This study determined if early changes in mammary morphology and the insulin-like growth factor (IGF)/estradiol axis are involved in the mechanisms that underlie this increased susceptibility. Pregnant Sprague-Dawley rats were fed a liquid diet containing 6.7% ethanol (alcohol), an isocaloric liquid diet (pair-fed), or rat chow ad libitum from days 11 to 21 of gestation. At birth, female pups were cross-fostered to ad libitum-fed control dams. Offspring were euthanized at postnatal days (PND) 20, 40, or 80. Animals were injected with BrdU before euthanasia, then mammary glands, serum, and livers were collected. Mammary glands from animals exposed to alcohol in utero displayed increased epithelial cell proliferation and aromatase expression at PND 20 and 40. Mammary IGF-I mRNA was higher in alcohol-exposed animals relative to controls at PND 20, while mammary IGFBP-5 mRNA was lower in this group at PND 40. Hepatic IGF-I mRNA expression was increased at all time points in alcohol-exposed animals, however, circulating IGF-I levels were not altered. These data indicate that alcohol exposure in utero may advance mammary development via the IGF and estradiol systems, which could contribute to increased susceptibility to mammary cancer later in life.

  12. Role of PTEN in the Tumor Microenvironment

    Science.gov (United States)

    2008-06-01

    mouse mammary tumors. Oncogene 24, 6870-6876. 11. Park ES, Lee JS, Woo HG, Zhan F, Shih JH, Shaughnessy JD Jr, Frederic Mushinski J. (2007...between: Pearson : p-value PTEN and ETS2-P (T72) -0.577 < 0.001 PTEN and AKT-P (S473) -0.552 < 0.001 ETS2-P (T72) and AKT-P (S473) 0.947 < 0.001 50μm

  13. Impact of Prostate Inflammation on Lesion Development in the POET3+Pten+/− Mouse Model of Prostate Carcinogenesis

    Science.gov (United States)

    Burcham, Grant N.; Cresswell, Gregory M.; Snyder, Paul W.; Chen, Long; Liu, Xiaoqi; Crist, Scott A.; Henry, Michael D.; Ratliff, Timothy L.

    2015-01-01

    Evidence linking prostatitis and prostate cancer development is contradictory. To study this link, the POET3 mouse, an inducible model of prostatitis, was crossed with a Pten-loss model of prostate cancer (Pten+/−) containing the ROSA26 luciferase allele to monitor prostate size. Prostatitis was induced, and prostate bioluminescence was tracked over 12 months, with lesion development, inflammation, and cytokine expression analyzed at 4, 8, and 12 months and compared with mice without induction of prostatitis. Acute prostatitis led to more proliferative epithelium and enhanced bioluminescence. However, 4 months after initiation of prostatitis, mice with induced inflammation had lower grade pre-neoplastic lesions. A trend existed toward greater development of carcinoma 12 months after induction of inflammation, including one of two mice with carcinoma developing perineural invasion. Two of 18 mice at the later time points developed lesions with similarities to proliferative inflammatory atrophy, including one mouse with associated carcinoma. Pten+/− mice developed spontaneous inflammation, and prostatitis was similar among groups of mice at 8 and 12 months. Analyzed as one cohort, lesion number and grade were positively correlated with prostatitis. Specifically, amounts of CD11b+Gr1+ cells were correlated with lesion development. These results support the hypothesis that myeloid-based inflammation is associated with lesion development in the murine prostate, and previous bouts of CD8-driven prostatitis may promote invasion in the Pten+/− model of cancer. PMID:25455686

  14. PTEN and p53 cross-regulation induced by soy isoflavone genistein promotes mammary epithelial cell cycle arrest and lobuloalveolar differentiation

    Science.gov (United States)

    The tumor suppressors PTEN and p53 are closely related to the pathogenesis of breast cancer, yet pathway-specific mechanisms underlying their participation in mediating the protective actions of dietary bioactive components on breast cancer risk are poorly understood. We recently showed that dietary...

  15. FEEDING GENISTEIN TO PREPUBERTAL GILTS STIMULATES THEIR MAMMARY DEVELOPMENT

    Science.gov (United States)

    The possible role of dietary genistein on mammary development of prepubertal gilts was investigated. Forty-five gilts were fed one of three diets from 90 d of age until slaughter (day 183 ± 1). Diets were: without soya (CTL0, n=15); soya-based commercial (CTLS, n=15); and soya-based commercial with ...

  16. DEVELOPMENT OF HUMAN MAMMARY GLAND - A PRENATAL STU DY

    Directory of Open Access Journals (Sweden)

    Rachna

    2012-12-01

    Full Text Available ABSTRACT: 44 fetuses of varying gestational ages, ranging fr om 33m.m C.R.L. to 270m.m.C.R.L. (i.e. from 8weeks to 32weeks of intrauterine life were studied to note the developmental sequence of mammary gland. Tissues were prepared for microtomy by Paraffin wax embedding method. Serial sections were stained by Haematoxyli n & Eosin (H & E and Masson’s Trichome method(1. It was observed that the organ is subjec t to fluctuations in its development. In the present study the primary bud, secondary bud, & terti ary bud formation is seen at11th week ,14th week & 18 th week of gestation respectively .The canalization appeared at 20 th week of gestation. Variation is seen in the mode of canal ization as well as in the time of start of canalization. In the present study an endeavour has been made to establish the time of appearance of mammary buds and their time of canaliza tion .The observations are compared with the findings of other workers and discussed in the light of literature. Mammogenesis or development of mammary gland is of great importance for anatomists, surgeons, pathologists, physicians, obstetricians etc. A large number of dev elopmental anomalies like amastia, athelia, polymastia, polythelia, etc are of interest to them w hich can be understood more if thorough understanding of development of mammary gland is th ere.

  17. RUNX2 in mammary gland development and breast cancer.

    Science.gov (United States)

    Ferrari, Nicola; McDonald, Laura; Morris, Joanna S; Cameron, Ewan R; Blyth, Karen

    2013-06-01

    Runx2 is best known as an essential factor in osteoblast differentiation and bone development but, like many other transcription factors involved in development, is known to operate over a much wider tissue range. Our understanding of these other aspects of Runx2 function is still at a relatively early stage and the importance of its role in cell fate decisions and lineage maintenance in non-osseous tissues is only beginning to emerge. One such tissue is the mammary gland, where Runx2 is known to be expressed and participate in the regulation of mammary specific genes. Furthermore, differential and temporal expression of this gene is observed during mammary epithelial differentiation in vivo, strongly indicative of an important functional role. Although the precise nature of that role remains elusive, preliminary evidence hints at possible involvement in the regulation of mammary stem and/or progenitor cells. As with many genes important in regulating cell fate, RUNX2 has also been linked to metastatic cancer where in some established breast cell lines, retention of expression is associated with a more invasive phenotype. More recently, expression analysis has been extended to primary breast cancers where high levels of RUNX2 align with a specific subtype of the disease. That RUNX2 expression correlates with the so called "Triple Negative" subtype is particularly interesting given the known cross talk between Runx2 and estrogen receptor signaling pathways. This review summaries our current understanding of Runx2 in mammary gland development and cancer, and postulates a role that may link both these processes.

  18. Soy peptide lunasin induces pten-mediated apoptosis in human breast cancer cells

    Science.gov (United States)

    The tumor suppressor PTEN inhibits the AKT signaling pathway whose unrestrained activity underlies many human malignancies. Previously we showed that dietary intake of soy protein isolate (SPI) enhanced PTEN expression in mammary tissue of rats with lower NMU-induced mammary tumor incidence relative...

  19. Mammary gland development: cell fate specification, stem cells and the microenvironment.

    Science.gov (United States)

    Inman, Jamie L; Robertson, Claire; Mott, Joni D; Bissell, Mina J

    2015-03-15

    The development of the mammary gland is unique: the final stages of development occur postnatally at puberty under the influence of hormonal cues. Furthermore, during the life of the female, the mammary gland can undergo many rounds of expansion and proliferation. The mammary gland thus provides an excellent model for studying the 'stem/progenitor' cells that allow this repeated expansion and renewal. In this Review, we provide an overview of the different cell types that constitute the mammary gland, and discuss how these cell types arise and differentiate. As cellular differentiation cannot occur without proper signals, we also describe how the tissue microenvironment influences mammary gland development.

  20. Serotoninergic and circadian systems: driving mammary gland development and function

    Directory of Open Access Journals (Sweden)

    Aridany Suárez-Trujillo

    2016-07-01

    Full Text Available Since lactation is one of the most metabolically demanding states in adult female mammals, beautifully complex regulatory mechanisms are in place to time lactation to begin after birth and cease when the neonate is weaned. Lactation is regulated by numerous different homeorhetic factors, all of them tightly coordinated with the demands of milk production. Emerging evidence support that among these factors are the serotonergic and circadian clock systems. Here we review the serotoninergic and circadian clock systems and their roles in the regulation of mammary gland development and lactation physiology. We conclude by presenting our hypothesis that these two systems interact to accommodate the metabolic demands of lactation and thus adaptive changes in these systems occur to maintain mammary and systemic homeostasis through the reproductive cycles of female mammals.

  1. The soybean peptide lunasin promotes apoptosis of mammary epithelial cells via induction of tumor suppressor PTEN: similarities and distinct actions from soy isoflavone genistein

    Science.gov (United States)

    Breast cancer is the leading cause of cancer deaths in women. Diet and lifestyle are major contributing factors to increased breast cancer risk. While mechanisms underlying dietary protection of mammary tumor formation are increasingly elucidated, there remains a dearth of knowledge on the nature an...

  2. Perinatal ethinyl oestradiol alters mammary gland development in male and female Wistar rats

    DEFF Research Database (Denmark)

    Mandrup, Karen; Hass, Ulla; Christiansen, Sofie

    2012-01-01

    Increased attention is being paid to human mammary gland development because of concerns for environmental influences on puberty onset and breast cancer development. Studies in rodents have showed a variety of changes in the mammary glands after perinatal exposure to endocrine disrupting chemical...... exposures may alter mammary gland development, disrupt lactation and alter susceptibility to breast cancer.......Increased attention is being paid to human mammary gland development because of concerns for environmental influences on puberty onset and breast cancer development. Studies in rodents have showed a variety of changes in the mammary glands after perinatal exposure to endocrine disrupting chemicals......, Wistar rats were exposed to 0, 5, 15 or 50 μg/kg of ethinyl oestradiol per day during gestation and lactation. A wide range of morphological parameters were evaluated in whole mounts of mammary glands from male and female offspring PD21–22. This study showed that in both male and female pre...

  3. Role of Fibroblast Growth Factor Binding Protein-1 in Mammary Development and Tumorigenesis

    Science.gov (United States)

    2009-10-01

    2002) and parathyroid related hormone (Wysolmerski et al. 1998). Here we have focused on the effects that FGF may have on the mammary gland and...mammary gland development, reduced tertiary branching, apoptosis, HER2/neu mice 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18...inducible system. Preliminary data indicate a striking decrease in the lateral budding of mammary glands in animals expressing BP1. Matrigel plug assays

  4. Key stages in mammary gland development: the mammary end bud as a motile organ.

    Science.gov (United States)

    Hinck, Lindsay; Silberstein, Gary B

    2005-01-01

    In the rodent, epithelial end buds define the tips of elongating mammary ducts. These highly motile structures undergo repeated dichotomous branching as they aggressively advance through fatty stroma and, turning to avoid other ducts, they finally cease growth leaving behind the open, tree-like framework on which secretory alveoli develop during pregnancy. This review identifies the motility of end buds as a unique developmental marker that represents the successful integration of systemic and local mammotrophic influences, and covers relevant advances in ductal growth regulation, extracellular matrix (ECM) remodeling, and cell adhesion in the inner end bud. An unexpected growth-promoting synergy between insulin-like growth factor-1 and progesterone, in which ducts elongate without forming new end buds, is described as well as evidence strongly supporting self-inhibition of ductal elongation by end-bud-secreted transforming growth factor-beta acting on stromal targets. The influence of the matrix metalloproteinase ECM-remodeling enzymes, notably matrix metalloproteinase-2, on end bud growth is discussed in the broader context of enzymes that regulate the polysaccharide-rich glycosaminoglycan elements of the ECM. Finally, a critical, motility-enabling role for the cellular architecture of the end bud is identified and the contribution of cadherins, the netrin/neogenin system, and ErbB2 to the structure and motility of end buds is discussed.

  5. Biological Function of Plasma Kallikrein in Mammary Gland Stromal Development and Tumor Metastasis

    Science.gov (United States)

    2008-03-01

    L.A. Dent. 2003. Interleukin-5 transgene expression and eosinophilia are associated with retarded mammary gland development in mice. Biology of...and L.A. Dent. 2003. Interleukin-5 transgene expression and eosinophilia are associated with retarded mammary gland development in mice. Biology of

  6. The biology of zinc transport in mammary epithelial cells: implications for mammary gland development, lactation, and involution.

    Science.gov (United States)

    McCormick, Nicholas H; Hennigar, Stephen R; Kiselyov, Kirill; Kelleher, Shannon L

    2014-03-01

    Zinc plays a critical role in a vast array of cellular functions including gene transcription, protein translation, cell proliferation, differentiation, bioenergetics, and programmed cell death. The mammary gland depends upon tight coordination of these processes during development and reproduction for optimal expansion, differentiation, and involution. For example, zinc is required for activation of matrix metalloproteinases, intracellular signaling cascades such as MAPK and PKC, and the activation of both mitochondrial-mediated apoptosis and lysosomal-mediated cell death. In addition to functional needs, during lactation the mammary gland must balance providing optimal zinc for cellular requirements with the need to secrete a substantial amount of zinc into milk to meet the requirements of the developing neonate. Finally, the mammary gland exhibits the most profound example of programmed cell death, which is driven by both apoptotic and lysosomal-mediated cell death. Two families of zinc-specific transporters regulate zinc delivery for these diverse functions. Members of the ZIP family of zinc transporters (ZIP1-14) import zinc into the cytoplasm from outside the cell or from subcellular organelles, while members of the ZnT family (ZnT1-10) export zinc from the cytoplasm. Recently, the ion channel transient receptor potential mucolipin 1 (TRPML1) has also been implicated in zinc transport. Herein, we review our current understanding of the molecular mechanisms through which mammary epithelial cells utilize zinc with a focus on the transport of zinc into discrete subcellular organelles for specific cellular functions during mammary gland development, lactation, and involution.

  7. Interplay between progesterone and prolactin in mammary development and implications for breast cancer.

    Science.gov (United States)

    Lee, Heather J; Ormandy, Christopher J

    2012-06-24

    Progesterone and prolactin remodel mammary morphology during pregnancy by acting on the mammary epithelial cell hierarchy. The roles of each hormone in mammary development have been well studied, but evidence of signalling cross-talk between progesterone and prolactin is still emerging. Factors such as receptor activator of NFkB ligand (RANKL) may integrate signals from both hormones to orchestrate their joint actions on the epithelial cell hierarchy. Common targets of progesterone and prolactin signalling are also likely to integrate their pro-proliferative actions in breast cancer. Therefore, a thorough understanding of the interplay between progesterone and prolactin in mammary development may reveal therapeutic targets for breast cancer. This review summarises our understanding of Pg and PRL action in mammary gland development before focusing on molecular mechanisms of signalling cross-talk and the implications for breast cancer. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Relationship between histology, development and tumorigenesis of mammary gland in female rat

    Science.gov (United States)

    LÍŠKA, Ján; BRTKO, Július; DUBOVICKÝ, Michal; MACEJOVÁ, Dana; KISSOVÁ, Viktória; POLÁK, Štefan; UJHÁZY, Eduard

    2015-01-01

    The mammary gland is a dynamic organ that undergoes structural and functional changes associated with growth, reproduction, and post-menopausal regression. The postnatal transformations of the epithelium and stromal cells of the mammary gland may contribute to its susceptibility to carcinogenesis. The increased cancer incidence in mammary glands of humans and similarly of rodents in association with their development is believed to be partly explained by proliferative activity together with lesser degree of differentiation, but it is not completely understood how the virgin gland retains its higher susceptibility to carcinogenesis. During its developmental cycle, the mammary gland displays many of the properties associated with breast cancer. An early first full-term pregnancy may have a protective effect. Rodent models are useful for investigating potential breast carcinogens. The purpose of this review is to help recognizing histological appearance of the epithelium and the stroma of the normal mammary gland in rats, and throughout its development in relation to tumorigenic potential. PMID:26424555

  9. Unlocking the milk protein gene loci during mammary gland development and differentiation; a role for chromatin

    Science.gov (United States)

    Mammary gland development and differentiation occur mostly postnatally. Chromatin organization plays a key role in transcriptional and epigenetic regulation during development and differentiation. Considerable knowledge of the systemic hormones and local growth factors important for development and ...

  10. Mammary gland specific knockdown of the physiological surge in Cx26 during lactation retains normal mammary gland development and function.

    Directory of Open Access Journals (Sweden)

    Michael K G Stewart

    Full Text Available Connexin26 (Cx26 is the major Cx protein expressed in the human mammary gland and is up-regulated during pregnancy while remaining elevated throughout lactation. It is currently unknown if patients with loss-of-function Cx26 mutations that result in hearing loss and skin diseases have a greater susceptibility to impaired breast development. To investigate if Cx26 plays a critical role in mammary gland development and differentiation, a novel Cx26 conditional knockout mouse model was generated by crossing Cx26fl/fl mice with mice expressing Cre under the β-Lactoglobulin promoter. Conditional knockdown of Cx26 from the mammary gland resulted in a dramatic reduction in detectable gap junction plaques confirmed by a significant ∼65-70% reduction in Cx26 mRNA and protein throughout parturition and lactation. Interestingly, this reduction was accompanied by a decrease in mammary gland Cx30 gap junction plaques at parturition, while no change was observed for Cx32 or Cx43. Whole mount, histological and immunofluorescent assessment of breast tissue revealed comparatively normal lobuloalveolar development following pregnancy in the conditionally knockdown mice compared to control mice. In addition, glands from genetically-modified mice were capable of producing milk proteins that were evident in the lumen of alveoli and ducts at similar levels as controls, suggesting normal gland function. Together, our results suggest that low levels of Cx26 expression throughout pregnancy and lactation, and not the physiological surge in Cx26, is sufficient for normal gland development and function.

  11. Lentiviral Transduction of Mammary Stem Cells for Analysis of Gene Function during Development and Cancer

    Science.gov (United States)

    Welm, Bryan E.; Dijkgraaf, Gerrit J. P.; Bledau, Anita S.; Welm, Alana L.; Werb, Zena

    2008-01-01

    SUMMARY The mouse mammary gland is the only epithelial organ capable of complete regeneration upon orthotopic transplantation, making it ideally suited for in vivo gene function studies through viral mediated gene delivery. A hurdle that has challenged the widespread adoption of this technique has been the inability to transduce mammary stem cells effectively. We have overcome this limitation by infecting total primary mammary epithelial cells in suspension with high titer lentiviruses. Transduced cells gave rise to all major cell types of the mammary gland, and were capable of clonal outgrowth and functional differentiation in serial transplants. To demonstrate that this method is a valuable alternative to developing transgenic animals, we used lentiviral-mediated Wnt-1 overexpression to replicate MMTV-Wnt-1 mammary phenotypes and used a dominant-negative Xenopus Suppressor of Hairless to reveal a requirement for Notch signaling during ductal morphogenesis. Importantly, this method is also applicable to transduction of cells from other tissues. PMID:18371425

  12. Mixtures of environmentally relevant endocrine disrupting chemicals affect mammary gland development in female and male rats.

    Science.gov (United States)

    Mandrup, Karen Riiber; Johansson, Hanna Katarina Lilith; Boberg, Julie; Pedersen, Anne Stilling; Mortensen, Mette Sidsel; Jørgensen, Jennifer Solgaard; Vinggaard, Anne Marie; Hass, Ulla

    2015-07-01

    Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action. Pregnant rat dams were exposed during gestation and lactation to mixtures of environmentally relevant EDCs with estrogenic, anti-androgenic or dissimilar modes of action (TotalMix) of 100-, 200- or 450-fold high end human intake estimates. Mammary glands of prepubertal and adult female and male offspring were examined. Oestrogens increased mammary outgrowth in prepubertal females and the mRNA level of matrix metalloproteinase-3, which may be a potential biomarker for increased outgrowth. Mixtures of EDCs gave rise to ductal hyperplasia in adult males. Adult female mammary glands of the TotalMix group showed morphological changes possibly reflecting increased prolactin levels. In conclusion both estrogenic and anti-androgenic chemicals given during foetal life and lactation affected mammary glands in the offspring.

  13. Mutant PTEN in Cancer : Worse Than Nothing

    NARCIS (Netherlands)

    Leslie, Nick R; den Hertog, Jeroen

    2014-01-01

    Tumor suppressors block the development of cancer and are often lost during tumor development. Papa et al. show that partial loss of normal PTEN tumor suppressor function can be compounded by additional disruption caused by the expression of inactive mutant PTEN protein. This has significant

  14. Mammary epithelial cell: Influence of extracellular matrix composition and organization during development and tumorigenesis

    Science.gov (United States)

    Kass, Laura; Erler, Janine T.; Dembo, Micah; Weaver, Valerie M.

    2009-01-01

    Stromal–epithelial interactions regulate mammary gland development and are critical for the maintenance of tissue homeostasis. The extracellular matrix, which is a proteinaceous component of the stroma, regulates mammary epithelial growth, survival, migration and differentiation through a repertoire of transmembrane receptors, of which integrins are the best characterized. Integrins modulate cell fate by reciprocally transducing biochemical and biophysical cues between the cell and the extracellular matrix, facilitating processes such as embryonic branching morphogenesis and lactation in the mammary gland. During breast development and cancer progression, the extracellular matrix is dynamically altered such that its composition, turnover, processing and orientation change dramatically. These modifications influence mammary epithelial cell shape, and modulate growth factor and hormonal responses to regulate processes including branching morphogenesis and alveolar differentiation. Malignant transformation of the breast is also associated with significant matrix remodeling and a progressive stiffening of the stroma that can enhance mammary epithelial cell growth, perturb breast tissue organization, and promote cell invasion and survival. In this review, we discuss the role of stromal–epithelial interactions in normal and malignant mammary epithelial cell behavior. We specifically focus on how dynamic modulation of the biochemical and biophysical properties of the extracellular matrix elicit a dialogue with the mammary epithelium through transmembrane integrin receptors to influence tissue morphogenesis, homeostasis and malignant transformation. PMID:17719831

  15. Tsc1 deficiency impairs mammary development in mice by suppression of AKT, nuclear ERα, and cell-cycle-driving proteins

    OpenAIRE

    Zhenqi Qin; Hang Zheng; Ling Zhou; Yanhua Ou; Bin Huang; Bo Yan; Zhenshu Qin; Cuilan Yang; Yongchun Su; Xiaochun Bai; Jiasong Guo; Jun Lin

    2016-01-01

    Loss of Tsc1/Tsc2 results in excess cell growth that eventually forms hamartoma in multiple organs. Our study using a mouse model with Tsc1 conditionally knockout in mammary epithelium showed that Tsc1 deficiency impaired mammary development. Phosphorylated S6 was up-regulated in Tsc1 −/− mammary epithelium, which could be reversed by rapamycin, suggesting that mTORC1 was hyperactivated in Tsc1 −/− mammary epithelium. The mTORC1 inhibitor rapamycin restored the development of Tsc1 −/− mammary...

  16. Loss of vitamin D receptor signaling from the mammary epithelium or adipose tissue alters pubertal glandular development.

    Science.gov (United States)

    Johnson, Abby L; Zinser, Glendon M; Waltz, Susan E

    2014-10-15

    Vitamin D₃ receptor (VDR) signaling within the mammary gland regulates various postnatal stages of glandular development, including puberty, pregnancy, involution, and tumorigenesis. Previous studies have shown that vitamin D₃ treatment induces cell-autonomous growth inhibition and differentiation of mammary epithelial cells in culture. Furthermore, mammary adipose tissue serves as a depot for vitamin D₃ storage, and both epithelial cells and adipocytes are capable of bioactivating vitamin D₃. Despite the pervasiveness of VDR in mammary tissue, individual contributions of epithelial cells and adipocytes, as well as the VDR-regulated cross-talk between these two cell types during pubertal mammary development, have yet to be investigated. To assess the cell-type specific effect of VDR signaling during pubertal mammary development, novel mouse models with mammary epithelial- or adipocyte-specific loss of VDR were generated. Interestingly, loss of VDR in either cellular compartment accelerated ductal morphogenesis with increased epithelial cell proliferation and decreased apoptosis within terminal end buds. Conversely, VDR signaling specifically in the mammary epithelium modulated hormone-induced alveolar growth, as ablation of VDR in this cell type resulted in precocious alveolar development. In examining cellular cross-talk ex vivo, we show that ligand-dependent VDR signaling in adipocytes significantly inhibits mammary epithelial cell growth in part through the vitamin D₃-dependent production of the cytokine IL-6. Collectively, these studies delineate independent roles for vitamin D₃-dependent VDR signaling in mammary adipocytes and epithelial cells in controlling pubertal mammary gland development.

  17. Emerging evidence of the physiological role of hypoxia in mammary development and lactation

    Institute of Scientific and Technical Information of China (English)

    Yong Shao; Feng-Qi Zhao

    2014-01-01

    Hypoxia is a physiological or pathological condition of a deficiency of oxygen supply in the body as a whole or within a tissue. During hypoxia, tissues undergo a series of physiological responses to defend themselves against a low oxygen supply, including increased angiogenesis, erythropoiesis, and glucose uptake. The effects of hypoxia are mainly mediated by hypoxia-inducible factor 1 (HIF-1), which is a heterodimeric transcription factor consisting ofαandβsubunits. HIF-1βis constantly expressed, whereas HIF-1αis degraded under normal oxygen conditions. Hypoxia stabilizes HIF-1αand the HIF complex, and HIF then translocates into the nucleus to initiate the expression of target genes. Hypoxia has been extensively studied for its role in promoting tumor progression, and emerging evidence also indicates that hypoxia may play important roles in physiological processes, including mammary development and lactation. The mammary gland exhibits an increasing metabolic rate from pregnancy to lactation to support mammary growth, lactogenesis, and lactation. This process requires increasing amounts of oxygen consumption and results in localized chronic hypoxia as confirmed by the binding of the hypoxia marker pimonidazole HCl in mouse mammary gland. We hypothesized that this hypoxic condition promotes mammary development and lactation, a hypothesis that is supported by the following several lines of evidence:i) Mice with an HIF-1αdeletion selective for the mammary gland have impaired mammary differentiation and lipid secretion, resulting in lactation failure and striking changes in milk compositions;ii) We recently observed that hypoxia significantly induces HIF-1α-dependent glucose uptake and GLUT1 expression in mammary epithelial cells, which may be responsible for the dramatic increases in glucose uptake and GLUT1 expression in the mammary gland during the transition period from late pregnancy to early lactation;and ii ) Hypoxia and HIF-1αincrease the

  18. Differential requirement of GRP94 and GRP78 in mammary gland development

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    Zhu, Genyuan; Wang, Miao; Spike, Benjamin; Gray, Peter C.; Shen, Jieli; Lee, Sung-Hyung; Chen, Si-Yi; Lee, Amy S.

    2014-01-01

    Glucose Regulated Protein (GRP) 94 and GRP78 are critical molecular chaperones and regulators of signaling. Conditional knockout mouse models have revealed tissue specific requirements for GRP94 and GRP78, including selection for allele retention in specific cell types. Here we report the consequences of mammary-targeted knockout of these GRPs. Our studies revealed that MMTV-Cre, Grp94f/f mammary glands, despite GRP94 deficiency, exhibited normal proliferation and ductal morphogenesis. Interestingly, MMTV-Cre, Grp78f/f mammary glands displayed only slightly reduced GRP78 protein levels, associating with the retention of the non-recombined Grp78 floxed alleles in isolated mammary epithelial cells and displayed phenotypes comparable to wild-type glands. In contrast, transduction of isolated Grp78f/f mammary epithelial stem/progenitor cells with adenovirus expressing GFP and Cre-recombinase was successful in GRP78 ablation, and the GFP sorted cells failed to give rise to repopulated mammary glands in de-epithelialized recipient mice. These studies imply GRP78, but not GRP94, is required for mammary gland development. PMID:24953136

  19. Hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers.

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    Kohnoh, Takashi; Hashimoto, Naozumi; Ando, Akira; Sakamoto, Koji; Miyazaki, Shinichi; Aoyama, Daisuke; Kusunose, Masaaki; Kimura, Motohiro; Omote, Norihito; Imaizumi, Kazuyoshi; Kawabe, Tsutomu; Hasegawa, Yoshinori

    2016-01-01

    Persistent hypoxia stimulation, one of the most critical microenvironmental factors, accelerates the acquisition of epithelial-mesenchymal transition (EMT) phenotypes in lung cancer cells. Loss of phosphatase and tensin homologue deleted from chromosome 10 (PTEN) expression might accelerate the development of lung cancer in vivo. Recent studies suggest that tumor microenvironmental factors might modulate the PTEN activity though a decrease in total PTEN expression and an increase in phosphorylation of the PTEN C-terminus (p-PTEN), resulting in the acquisition of the EMT phenotypes. Nevertheless, it is not known whether persistent hypoxia can modulate PTEN phosphatase activity or whether hypoxia-induced EMT phenotypes are negatively regulated by the PTEN phosphatase activity. We aimed to investigate hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers. Western blotting was performed in five lung cancer cell lines to evaluate total PTEN expression levels and the PTEN activation. In a xenograft model of lung cancer cells with endogenous PTEN expression, the PTEN expression was evaluated by immunohistochemistry. To examine the effect of hypoxia on phenotypic alterations in lung cancer cells in vitro, the cells were cultured under hypoxia. The effect of unphosphorylated PTEN (PTEN4A) induction on hypoxia-induced EMT phenotypes was evaluated, by using a Dox-dependent gene expression system. Lung cancer cells involving the EMT phenotypes showed a decrease in total PTEN expression and an increase in p-PTEN. In a xenograft model, loss of PTEN expression was observed in the tumor lesions showing tissue hypoxia. Persistent hypoxia yielded an approximately eight-fold increase in the p-PTEN/PTEN ratio in vitro. PTEN4A did not affect stabilization of hypoxia-inducible factor 1α. PTEN4A blunted hypoxia-induced EMT via inhibition of β-catenin translocation into the cytoplasm and nucleus. Our study strengthens the therapeutic possibility that

  20. Focus on PTEN regulation

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    Miriam eBermudez-Brito

    2015-07-01

    Full Text Available The role of PTEN as a tumour suppressor has been for a long time attributed to its lipid phosphatase activity against PI(3,4,5P3, the phospholipid product of the class I PI3Ks. Besides its traditional role as a lipid phosphatase at the plasma membrane, a wealth of data has shown that PTEN can function independently of its phosphatase activity and that PTEN also exists and plays a role in the nucleus, in cytoplasmic organelles and extracellularly. Accumulating evidence has shed light on diverse physiological functions of PTEN which are accompanied by a complex regulation of its expression and activity. PTEN levels and function are regulated transcriptionally, post-transcriptionally and post-translationally. PTEN is also sensitive to regulation by its interacting proteins and its localization. Herein, we summarize the current knowledge on mechanisms that regulate the expression and enzymatic activity of PTEN and its role in human diseases.

  1. Characterisation of microRNA expression in post-natal mouse mammary gland development

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    Karagavriilidou Konstantina

    2009-11-01

    Full Text Available Abstract Background The differential expression pattern of microRNAs (miRNAs during mammary gland development might provide insights into their role in regulating the homeostasis of the mammary epithelium. Our aim was to analyse these regulatory functions by deriving a comprehensive tissue-specific combined miRNA and mRNA expression profile of post-natal mouse mammary gland development. We measured the expression of 318 individual murine miRNAs by bead-based flow-cytometric profiling of whole mouse mammary glands throughout a 16-point developmental time course, including juvenile, puberty, mature virgin, gestation, lactation, and involution stages. In parallel whole-genome mRNA expression data were obtained. Results One third (n = 102 of all murine miRNAs analysed were detected during mammary gland development. MicroRNAs were represented in seven temporally co-expressed clusters, which were enriched for both miRNAs belonging to the same family and breast cancer-associated miRNAs. Global miRNA and mRNA expression was significantly reduced during lactation and the early stages of involution after weaning. For most detected miRNA families we did not observe systematic changes in the expression of predicted targets. For miRNA families whose targets did show changes, we observed inverse patterns of miRNA and target expression. The data sets are made publicly available and the combined expression profiles represent an important community resource for mammary gland biology research. Conclusion MicroRNAs were expressed in likely co-regulated clusters during mammary gland development. Breast cancer-associated miRNAs were significantly enriched in these clusters. The mechanism and functional consequences of this miRNA co-regulation provide new avenues for research into mammary gland biology and generate candidates for functional validation.

  2. β-catenin is required for prostate development and cooperates with Pten loss to drive invasive carcinoma.

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    Jeffrey C Francis

    Full Text Available Prostate cancer is a major cause of male death in the Western world, but few frequent genetic alterations that drive prostate cancer initiation and progression have been identified. β-Catenin is essential for many developmental processes and has been implicated in tumorigenesis in many tissues, including prostate cancer. However, expression studies on human prostate cancer samples are unclear on the role this protein plays in this disease. We have used in vivo genetic studies in the embryo and adult to extend our understanding of the role of β-Catenin in the normal and neoplastic prostate. Our gene deletion analysis revealed that prostate epithelial β-Catenin is required for embryonic prostate growth and branching but is dispensable in the normal adult organ. During development, β-Catenin controls the number of progenitors in the epithelial buds and regulates a discrete network of genes, including c-Myc and Nkx3.1. Deletion of β-Catenin in a Pten deleted model of castration-resistant prostate cancer demonstrated it is dispensable for disease progression in this setting. Complementary overexpression experiments, through in vivo protein stabilization, showed that β-Catenin promotes the formation of squamous epithelia during prostate development, even in the absence of androgens. β-Catenin overexpression in combination with Pten loss was able to drive progression to invasive carcinoma together with squamous metaplasia. These studies demonstrate that β-Catenin is essential for prostate development and that an inherent property of high levels of this protein in prostate epithelia is to drive squamous fate differentiation. In addition, they show that β-Catenin overexpression can promote invasive prostate cancer in a clinically relevant model of this disease. These data provide novel information on cancer progression pathways that give rise to lethal prostate disease in humans.

  3. β-catenin is required for prostate development and cooperates with Pten loss to drive invasive carcinoma.

    Directory of Open Access Journals (Sweden)

    Jeffrey C Francis

    Full Text Available Prostate cancer is a major cause of male death in the Western world, but few frequent genetic alterations that drive prostate cancer initiation and progression have been identified. β-Catenin is essential for many developmental processes and has been implicated in tumorigenesis in many tissues, including prostate cancer. However, expression studies on human prostate cancer samples are unclear on the role this protein plays in this disease. We have used in vivo genetic studies in the embryo and adult to extend our understanding of the role of β-Catenin in the normal and neoplastic prostate. Our gene deletion analysis revealed that prostate epithelial β-Catenin is required for embryonic prostate growth and branching but is dispensable in the normal adult organ. During development, β-Catenin controls the number of progenitors in the epithelial buds and regulates a discrete network of genes, including c-Myc and Nkx3.1. Deletion of β-Catenin in a Pten deleted model of castration-resistant prostate cancer demonstrated it is dispensable for disease progression in this setting. Complementary overexpression experiments, through in vivo protein stabilization, showed that β-Catenin promotes the formation of squamous epithelia during prostate development, even in the absence of androgens. β-Catenin overexpression in combination with Pten loss was able to drive progression to invasive carcinoma together with squamous metaplasia. These studies demonstrate that β-Catenin is essential for prostate development and that an inherent property of high levels of this protein in prostate epithelia is to drive squamous fate differentiation. In addition, they show that β-Catenin overexpression can promote invasive prostate cancer in a clinically relevant model of this disease. These data provide novel information on cancer progression pathways that give rise to lethal prostate disease in humans.

  4. Endocrine hormones and local signals during the development of the mouse mammary gland.

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    Brisken, Cathrin; Ataca, Dalya

    2015-01-01

    Most of mammary gland development occurs postnatally under the control of female reproductive hormones, which in turn interact with other endocrine factors. While hormones impinge on many tissues and trigger very complex biological responses, tissue recombination experiments with hormone receptor-deficient mammary epithelia revealed eminent roles for estrogens, progesterone, and prolactin receptor (PrlR) signaling that are intrinsic to the mammary epithelium. A subset of the luminal mammary epithelial cells expresses the estrogen receptor α (ERα), the progesterone receptor (PR), and the PrlR and act as sensor cells. These cells convert the detected systemic signals into local signals that are developmental stage-dependent and may be direct, juxtacrine, or paracrine. This setup ensures that the original input is amplified and that the biological responses of multiple cell types can be coordinated. Some key mediators of hormone action have been identified such as Wnt, EGFR, IGFR, and RANK signaling. Multiple signaling pathways such as FGF, Hedgehog, and Notch signaling participate in driving different aspects of mammary gland development locally but how they link to the hormonal control remains to be elucidated. An increasing number of endocrine factors are appearing to have a role in mammary gland development, the adipose tissue is increasingly recognized to play a role in endocrine regulation, and a complex role of the immune system with multiple different cell types is being revealed. For further resources related to this article, please visit the WIREs website.

  5. Development and characterization of a novel rat model of estrogen-induced mammary cancer.

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    Dennison, Kirsten L; Samanas, Nyssa Becker; Harenda, Quincy Eckert; Hickman, Maureen Peters; Seiler, Nicole L; Ding, Lina; Shull, James D

    2015-04-01

    The ACI rat model of 17β-estradiol (E2)-induced mammary cancer is highly relevant for use in establishing the endocrine, genetic, and environmental bases of breast cancer etiology and identifying novel agents and strategies for preventing breast cancer. E2 treatment rapidly induces mammary cancer in female ACI rats and simultaneously induces pituitary lactotroph hyperplasia and adenoma. The pituitary tumors can result in undesired morbidity, which compromises long-term studies focused on mammary cancer etiology and prevention. We have defined the genetic bases of susceptibility to E2-induced mammary cancers and pituitary tumors and have utilized the knowledge gained in these studies to develop a novel inbred rat strain, designated ACWi, that retains the high degree of susceptibility to E2-induced mammary cancer exhibited by ACI rats, but lacks the treatment-related morbidity associated with pituitary lactotroph hyperplasia/adenoma. When treated with E2, female ACWi rats developed palpable mammary cancer at a median latency of 116 days, an incidence of 100% by 161 days and exhibited an average of 15.6 mammary tumors per rat following 196 days of treatment. These parameters did not differ from those observed for contemporaneously treated ACI rats. None of the E2-treated ACWi rats were killed before the intended experimental end point due to any treatment-related morbidity other than mammary cancer burden, whereas 20% of contemporaneously treated ACI rats exhibited treatment-related morbidity that necessitated premature killing. The ACWi rat strain is well suited for use by those in the research community, focusing on breast cancer etiology and prevention.

  6. Involvement of IGF-2, IGF-1R, IGF-2R and PTEN in development of human tooth germ – an immunohistochemical study

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    Kero, Darko; Cigic, Livia; Medvedec Mikic, Ivana; Galic, Tea; Cubela, Mladen; Vukojevic, Katarina; Saraga-Babic, Mirna

    2016-01-01

    ABSTRACT Insulin-Like Growth Factor 2 (IGF-2) is a peptide hormone essential for prenatal growth and development. IGF-2 exerts its mitogenic effects via Insulin-Like Growth Factor 1 Receptor (IGF-1R), and is eliminated by binding to Insulin-Like Growth Receptor 2 (IGF-2R). IGF-2 is also negatively regulated by Phosphatase and Tensin Homolog (PTEN), a phosphatase mutated in various tumors. Not much is known about the interplay between these factors during human odontogenesis. In this study, expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN were analyzed by double immunofluorescence in incisor human tooth germs during the foetal period of development between the 7th and 20th gestational week. Throughout the investigated period, IGF-2 was mostly expressed in enamel organ, whereas mild to moderate expression of PTEN could be seen in dental papilla and parts of enamel organ. Expression of IGF-1R was ubiquitous and displayed strong intensity throughout the entire enamel organ. In contrast, expression of IGF-2R had rather erratic pattern in enamel organ and dental papilla alike. Expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN in highly proliferative cervical loops, as well as in differentiating pre-ameloblasts and pre-odontoblasts of cusp tip region during the early and late bell stages when enamel organ acquires definitive shape, indicate importance of these factors in crown morphogenesis of human incisor. Taken together, our data suggest the involvement of IGF-2, IGF-1R, IGF-2R and PTEN in temporo-spatial patterning of basic cellular processes (proliferation, differentiation) during normal tooth development. They are also relevant for improving knowledge of molecular basis of human odontogenesis. PMID:27326759

  7. Involvement of IGF-2, IGF-1R, IGF-2R and PTEN in development of human tooth germ - an immunohistochemical study.

    Science.gov (United States)

    Kero, Darko; Cigic, Livia; Medvedec Mikic, Ivana; Galic, Tea; Cubela, Mladen; Vukojevic, Katarina; Saraga-Babic, Mirna

    2016-07-02

    Insulin-Like Growth Factor 2 (IGF-2) is a peptide hormone essential for prenatal growth and development. IGF-2 exerts its mitogenic effects via Insulin-Like Growth Factor 1 Receptor (IGF-1R), and is eliminated by binding to Insulin-Like Growth Receptor 2 (IGF-2R). IGF-2 is also negatively regulated by Phosphatase and Tensin Homolog (PTEN), a phosphatase mutated in various tumors. Not much is known about the interplay between these factors during human odontogenesis. In this study, expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN were analyzed by double immunofluorescence in incisor human tooth germs during the foetal period of development between the 7(th) and 20(th) gestational week. Throughout the investigated period, IGF-2 was mostly expressed in enamel organ, whereas mild to moderate expression of PTEN could be seen in dental papilla and parts of enamel organ. Expression of IGF-1R was ubiquitous and displayed strong intensity throughout the entire enamel organ. In contrast, expression of IGF-2R had rather erratic pattern in enamel organ and dental papilla alike. Expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN in highly proliferative cervical loops, as well as in differentiating pre-ameloblasts and pre-odontoblasts of cusp tip region during the early and late bell stages when enamel organ acquires definitive shape, indicate importance of these factors in crown morphogenesis of human incisor. Taken together, our data suggest the involvement of IGF-2, IGF-1R, IGF-2R and PTEN in temporo-spatial patterning of basic cellular processes (proliferation, differentiation) during normal tooth development. They are also relevant for improving knowledge of molecular basis of human odontogenesis.

  8. Reprogramming of the Tumor Microenvironment by Stromal Pten-regulated miR-320

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    Bronisz, A; Godlewski, J; Wallace, JA; Merchant, AS; Nowicki, MO; Mathsyaraja, H; Srinivasan, R; Trimboli, AJ; Martin, CK; Li, F; Yu, L; Fernandez, SA; Pécot, T; Rosol, TJ; Cory, S; Hallett, M; Park, M; Piper, MG; Marsh, CB; Yee, LD; Jimenez, RE; Nuovo, G; Lawler, SE; Chiocca, EA; Leone, G; Ostrowski, MC

    2011-01-01

    Phosphatase and tensin homolog deleted on chromosome ten (Pten) in stromal fibroblasts suppresses epithelial mammary tumors, but the underlying molecular mechanisms remain unknown. Using proteomic and expression profiling, we show that Pten loss from mammary stromal fibroblasts activates an oncogenic secretome that orchestrates the transcriptional reprogramming of other cell types in the microenvironment. Downregulation of miR-320 and upregulation of one of its direct targets, ETS2, are critical events in Pten-deleted stromal fibroblasts responsible for inducing this oncogenic secretome, which in turn promotes tumor angiogenesis and tumor cell invasion. Expression of the Pten-miR-320-Ets2 regulated secretome distinguished human normal breast stroma from tumor stroma and robustly correlated with recurrence in breast cancer patients. This work reveals miR-320 as a critical component of the Pten tumor suppressor axis that acts in stromal fibroblasts to reprogram the tumor microenvironment and curtail tumor progression. PMID:22179046

  9. Induction of PTEN-p53 crosstalk in mammary epithelial cells: A novel mechanism of breast cancer prevention by the dietary factor genistein

    Science.gov (United States)

    Consumption of soy foods either at an early age or for lifetime has been associated with reduced risk for developing breast cancer in humans and in animal models. However, this association continues to be controversial, and the precise mechanisms for protection remain elusive. Among the soy products...

  10. Key signalling nodes in mammary gland development and cancer. Mitogen-activated protein kinase signalling in experimental models of breast cancer progression and in mammary gland development.

    Science.gov (United States)

    Whyte, Jacqueline; Bergin, Orla; Bianchi, Alessandro; McNally, Sara; Martin, Finian

    2009-01-01

    Seven classes of mitogen-activated protein kinase (MAPK) intracellular signalling cascades exist, four of which are implicated in breast disease and function in mammary epithelial cells. These are the extracellular regulated kinase (ERK)1/2 pathway, the ERK5 pathway, the p38 pathway and the c-Jun N-terminal kinase (JNK) pathway. In some forms of human breast cancer and in many experimental models of breast cancer progression, signalling through the ERK1/2 pathway, in particular, has been implicated as being important. We review the influence of ERK1/2 activity on the organised three-dimensional association of mammary epithelial cells, and in models of breast cancer cell invasion. We assess the importance of epidermal growth factor receptor family signalling through ERK1/2 in models of breast cancer progression and the influence of ERK1/2 on its substrate, the oestrogen receptor, in this context. In parallel, we consider the importance of these MAPK-centred signalling cascades during the cycle of mammary gland development. Although less extensively studied, we highlight the instances of signalling through the p38, JNK and ERK5 pathways involved in breast cancer progression and mammary gland development.

  11. Loss of Panx1 Impairs Mammary Gland Development at Lactation: Implications for Breast Tumorigenesis

    Science.gov (United States)

    Stewart, Michael K. G.; Plante, Isabelle; Penuela, Silvia; Laird, Dale W.

    2016-01-01

    Pannexin1 (Panx1) subunits oligomerize to form large-pore channels between the intracellular and extracellular milieu that have been shown to regulate proliferation, differentiation and cell death mechanisms. These key cellular responses are ultimately necessary for normal tissue development and function but the role of Panx1 in development, differentiation and function in many tissues remains unexplored, including that of the breast. Panx1 was identified to be expressed in the mammary gland through western blot and immunofluorescent analysis and is dynamically upregulated during pregnancy and lactation. In order to evaluate the role of Panx1 in the context of mammary gland development and function, Panx1-/- mice were evaluated in comparison to wild-type mice in the mammary glands of virgin, lactating and involuting mice. Our results revealed that Panx1 ablation did not affect virgin or involuting mammary glands following histological and whole mount analysis. Panx1 was necessary for timely alveolar development during early lactation based on a decreased number of alveolar lumen following histological analysis and reduced proliferation following Ki67 immunofluorescent labelling. Importantly, the loss of Panx1 in lactating mammary glands did not overtly affect epithelial or secretory differentiation of the mammary gland suggesting that Panx1 is not critical in normal mammary gland function. In addition, PANX1 mRNA expression was correlated with negative clinical outcomes in patients with breast cancer using in silico arrays. Together, our results suggest that Panx1 is necessary for timely alveolar development following the transition from pregnancy to lactation, which may have implications extending to patients with breast cancer. PMID:27099931

  12. Inhibition of peripubertal sheep mammary gland development by cysteamine through reducing progesterone and growth factor production.

    Science.gov (United States)

    Zhao, Yong; Feng, Yanni; Zhang, Hongfu; Kou, Xin; Li, Lan; Liu, Xinqi; Zhang, Pengfei; Cui, Liantao; Chu, Meiqiang; Shen, Wei; Min, Lingjiang

    2017-02-01

    Cysteamine has been used for treating cystinosis for many years, and furthermore it has also been used as a therapeutic agent for different diseases including Huntington's disease, Parkinson's disease (PD), nonalcoholic fatty liver disease, malaria, cancer, and others. Although cysteamine has many potential applications, its use may also be problematic. The effects of low doses of cysteamine on the reproductive system, especially the mammary glands are currently unknown. In the current investigation, low dose (10 mg/kg BW/day) of cysteamine did not affect sheep body weight gain or organ index of the liver, spleen, or heart; it did, however, increase the levels of blood lymphocytes, monocytes, and platelets. Most interestingly, it inhibited mammary gland development after 2 or 5 months of treatment by reducing the organ index and the number of mammary gland ducts. Plasma growth hormone and estradiol remained unchanged; however, plasma progesterone levels and the protein level of HSD3β1 in sheep ovaries were decreased by cysteamine. In addition to steroid hormones, growth factors produced in the mammary glands also play crucial roles in mammary gland development. Results showed that protein levels of HGF, GHR, and IGF1R were decreased after 5 months of cysteamine treatment. These findings together suggest that progesterone and local growth factors in mammary glands might be involved in cysteamine initiated inhibition of pubertal ovine mammary gland development. Furthermore, it may lead to a reduction in fertility. Therefore, cysteamine should be used with great caution until its actions have been further investigated and its limitations overcome.

  13. Low-dose effects of bisphenol A on mammary gland development in rats.

    Science.gov (United States)

    Mandrup, K; Boberg, J; Isling, L K; Christiansen, S; Hass, U

    2016-07-01

    Bisphenol A (BPA) is widely used in food contact materials, toys, and other products. Several studies have indicated that effects observed at doses near human exposure levels may not be observed at higher doses. Many studies have shown effects on mammary glands at low doses of BPA, however, because of small number of animals or few doses investigated these data have not been used by EFSA as point of departure for the newly assessed tolerable daily intake (TDI). We performed a study with perinatal exposure to BPA (0, 0.025, 0.25, 5, and 50 mg/kg bw/day) in rats (n = 22 mated/group). One of the aims was to perform a study robust enough to contribute to the risk assessment of BPA and to elucidate possible biphasic dose-response relationships. We investigated mammary gland effects in the offspring at 22, 100, and 400 days of age. Male offspring showed increased mammary outgrowth on pup day (PD) 22 at 0.025 mg/kg BPA, indicating an increased mammary development at this low dose only. Increased prevalence of intraductal hyperplasia was observed in BPA females exposed to 0.25 mg/kg at PD 400, but not at PD 100, and not at higher or lower doses. The present findings support data from the published literature showing that perinatal exposure to BPA can induce increased mammary growth and proliferative lesions in rodents. Our results indicate that low-dose exposure to BPA can affect mammary gland development in male and female rats, although higher doses show a different pattern of effects. The observed intraductal hyperplasia in female rats could be associated with an increased risk for developing hyperplastic lesions, which are parallels to early signs of breast neoplasia in women. Collectively, current knowledge on effects of BPA on mammary gland at low doses indicates that highly exposed humans may not be sufficiently protected.

  14. Estrogen receptor coregulators and pioneer factors: The orchestrators of mammary gland cell fate and development

    Directory of Open Access Journals (Sweden)

    Bramanandam eManavathi

    2014-08-01

    Full Text Available The 17-beta estradiol (E2, a steroid hormone, which play critical role in various cellular processes such as cell proliferation, differentiation, migration and apoptosis, is essential for reproduction and mammary gland development. E2 actions are mediated by two classical nuclear hormone receptors, estrogen receptor alpha and beta (ERs. The activity of ERs depends on the coordinate activity of ligand binding, posttranslational modification, and importantly their interaction with their partner proteins called ‘coregulators’. Because majority of breast cancers are ERalpha positive and coregulators are proved to be crucial for ER transcriptional activity, an increased interest in the field has led to the identification of a large number of coregulators. In the last decade, gene knockout studies using mouse models provided impetus to our further understanding of the role of these coregulators in mammary gland development. Several coregulators appear to be critical for terminal end bud formation, ductal branching and alveologenesis during mammary gland development. The emerging studies support that, in addition to these coregulators, the other ER partner proteins ‘pioneering factors’ also seems to contribute significantly to E2 signaling and mammary cell fate. This review discusses emerging themes in coregulator- and pioneering factor-mediated action on ER functions, particularly their role in mammary gland cell fate and development.

  15. Integrated extracellular matrix signaling in mammary gland development and breast cancer progression.

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    Zhu, Jieqing; Xiong, Gaofeng; Trinkle, Christine; Xu, Ren

    2014-09-01

    Extracellular matrix (ECM), a major component of the cellular microenvironment, plays critical roles in normal tissue morphogenesis and disease progression. Binding of ECM to membrane receptor proteins, such as integrin, discoidin domain receptors, and dystroglycan, elicits biochemical and biomechanical signals that control cellular architecture and gene expression. These ECM signals cooperate with growth factors and hormones to regulate cell migration, differentiation, and transformation. ECM signaling is tightly regulated during normal mammary gland development. Deposition and alignment of fibrillar collagens direct migration and invasion of mammary epithelial cells during branching morphogenesis. Basement membrane proteins are required for polarized acinar morphogenesis and milk protein expression. Deregulation of ECM proteins in the long run is sufficient to promote breast cancer development and progression. Recent studies demonstrate that the integrated biophysical and biochemical signals from ECM and soluble factors are crucial for normal mammary gland development as well as breast cancer progression.

  16. Role of miRNA in Mammary Gland Development and Lactation

    Institute of Scientific and Technical Information of China (English)

    Li Qing-zhang; Wang Chun-mei; Gao Xue-jun

    2014-01-01

    miRNA can regulate development and milk yield of the mammary gland through epigenetic mechanism. miRNA can directly and indirectly modulate the activity of the epigenetic machinery, target genes through post-inhibition of translation initiation, mediate miRNA decay, target genes and inhibit the positive regulation, regulate tone modification, and regulate DNA methylation of target genes. Here we reviewed the role of miRNAs in mammary gland development and lactation. Researching miRNA in mammary gland development and lactation process, and understanding the response of the epigenetic mechanisms to external stimuli will be an important necessity to devise new technologies for maximizing their activity and milk production in the dairy cow.

  17. Epigenetic Modifications Unlock the Milk Protein Gene Loci during Mouse Mammary Gland Development and Differentiation

    Science.gov (United States)

    Rijnkels, Monique; Freeman-Zadrowski, Courtneay; Hernandez, Joseph; Potluri, Vani; Wang, Liguo; Li, Wei; Lemay, Danielle G.

    2013-01-01

    Background Unlike other tissues, development and differentiation of the mammary gland occur mostly after birth. The roles of systemic hormones and local growth factors important for this development and functional differentiation are well-studied. In other tissues, it has been shown that chromatin organization plays a key role in transcriptional regulation and underlies epigenetic regulation during development and differentiation. However, the role of chromatin organization in mammary gland development and differentiation is less well-defined. Here, we have studied the changes in chromatin organization at the milk protein gene loci (casein, whey acidic protein, and others) in the mouse mammary gland before and after functional differentiation. Methodology/Principal Findings Distal regulatory elements within the casein gene cluster and whey acidic protein gene region have an open chromatin organization after pubertal development, while proximal promoters only gain open-chromatin marks during pregnancy in conjunction with the major induction of their expression. In contrast, other milk protein genes, such as alpha-lactalbumin, already have an open chromatin organization in the mature virgin gland. Changes in chromatin organization in the casein gene cluster region that are present after puberty persisted after lactation has ceased, while the changes which occurred during pregnancy at the gene promoters were not maintained. In general, mammary gland expressed genes and their regulatory elements exhibit developmental stage- and tissue-specific chromatin organization. Conclusions/Significance A progressive gain of epigenetic marks indicative of open/active chromatin on genes marking functional differentiation accompanies the development of the mammary gland. These results support a model in which a chromatin organization is established during pubertal development that is then poised to respond to the systemic hormonal signals of pregnancy and lactation to achieve the

  18. The pivotal role of insulin-like growth factor I in normal mammary development.

    Science.gov (United States)

    Kleinberg, David L; Barcellos-Hoff, Mary Helen

    2011-09-01

    Mammary development begins in puberty in response to an estrogen (E(2)) surge. E(2) does not act alone. It relies on pituitary growth hormone (GH) to induce insulin-like growth factor I (IGF-I) production in the mammary stromal compartment. In turn, IGF-I permits E(2) (and progesterone) action. During puberty, E(2) and IGF-I synergize for ductal morphogenesis. During pregnancy, progesterone joins IGF-I and E(2) to stimulate secretory differentiation necessary to produce milk. Prolactin stimulates milk production, while transforming growth factor-β inhibits proliferation. The orchestrated action of hormones, growth factors, and receptors necessary for mammary development and function are also critical in breast cancer.

  19. The Expression of the IGF Family During Mouse Mammary Gland Development

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study was to determine the patterns and levels of IGF family members' expression during postnatal mammary gland development. The authors investigated the protein expression profile of the major components of the IGF axis in murine mammary glands. All the proteins examined, IGF- Ⅰ, IGF- Ⅱ, and IGF- Ⅰ receptor (IGF- Ⅰ R) were expressed at greatly different levels and displayed unique expression profiles. IGF- Ⅱ and IGF- Ⅰ R were always expressed at significantly higher levels than IGF- Ⅰ. IGF- Ⅰ was localized in adipocytes as well as the epithelial and stromal compartments, but just distinctly expressed where mammary cells aggregated to form ducts, in virgins. The IGF- Ⅱ was localized only on the basal layer epithelial cell membranes of ducts and alveoli, with a peak level on the initiation of lactation. The higher level of IGF- Ⅰ R compared with IGF- Ⅰ was also found in adipocytes as well as in the epithelial and stromal compartments, especially during pregnancy and late lactation. The IGF- Ⅰ R pathway was obviously significant for the development of the mammary parenchyma and stroma. Overall, the comparison of the expression profiles of these different proteins would strongly suggest that they were likely to have different functions throughout the mammary gland development, and it also highlighted the potential interactions and coregulation of the members of this axis. It seems that IGF- Ⅱ was the major local modulator rather than IGF- Ⅰ by an IGF- Ⅰ R-independent pathway, especially for initiation of lactation. This study has demonstrated the importance and complexity of the IGF axis during mammary gland development and provides a valuable resource for future research in this area.

  20. Epigenetic modifications unlock the milk protein gene loci during mouse mammary gland development and differentiation

    Science.gov (United States)

    Unlike with other tissues, development and differentiation of the mammary gland occur mostly after birth. The roles of systemic hormones and local growth factors important for this development and functional differentiation are well-studied. In other tissues, it has been shown that chromatin organiz...

  1. New methods in mammary gland development and cancer: proteomics, epigenetics, symmetric division and metastasis

    OpenAIRE

    Bentires-Alj, Mohamed; Glukhova, Marina; Hynes, Nancy; Vivanco, Maria dM.

    2012-01-01

    The European Network for Breast Development and Cancer (ENBDC) meeting on 'Methods in Mammary Gland Development and Cancer' has become an annual international rendezvous for scientists with interests in the normal and neoplastic breast. The fourth meeting in this series, held in April in Weggis, Switzerland, focused on proteomics, epigenetics, symmetric division, and metastasis.

  2. Growth hormone and insulin-like growth factor-I in the transition from normal mammary development to preneoplastic mammary lesions.

    Science.gov (United States)

    Kleinberg, David L; Wood, Teresa L; Furth, Priscilla A; Lee, Adrian V

    2009-02-01

    Adult female mammary development starts at puberty and is controlled by tightly regulated cross-talk between a group of hormones and growth factors. Although estrogen is the initial driving force and is joined by luteal phase progesterone, both of these hormones require GH-induced IGF-I in the mammary gland in order to act. The same group of hormones, when experimentally perturbed, can lead to development of hyperplastic lesions and increase the chances, or be precursors, of mammary carcinoma. For example, systemic administration of GH or IGF-I causes mammary hyperplasia, and overproduction of IGF-I in transgenic animals can cause the development of usual or atypical hyperplasias and sometimes carcinoma. Although studies have clearly demonstrated the transforming potential of both GH and IGF-I receptor in cell culture and in animals, debate remains as to whether their main role is actually instructive or permissive in progression to cancer in vivo. Genetic imprinting has been shown to occur in precursor lesions as early as atypical hyperplasia in women. Thus, the concept of progression from normal development to cancer through precursor lesions sensitive to hormones and growth factors discussed above is gaining support in humans as well as in animal models. Indeed, elevation of estrogen receptor, GH, IGF-I, and IGF-I receptor during progression suggests a role for these pathways in this process. New agents targeting the GH/IGF-I axis may provide a novel means to block formation and progression of precursor lesions to overt carcinoma. A novel somatostatin analog has recently been shown to prevent mammary development in rats via targeted IGF-I action inhibition at the mammary gland. Similarly, pegvisomant, a GH antagonist, and other IGF-I antagonists such as IGF binding proteins 1 and 5 also block mammary gland development. It is, therefore, possible that inhibition of IGF-I action, or perhaps GH, in the mammary gland may eventually play a role in breast cancer

  3. Mixtures of environmentally relevant endocrine disrupting chemicals affect mammary gland development in female and male rats

    DEFF Research Database (Denmark)

    Mandrup, Karen Riiber; Johansson, Hanna Katarina Lilith; Boberg, Julie

    2015-01-01

    Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action. Pregnant rat dams were exposed during gestation and lactation to mixtures...... and the mRNA level of matrix metalloproteinase-3, which may be a potential biomarker for increased outgrowth. Mixtures of EDCs gave rise to ductal hyperplasia in adult males. Adult female mammary glands of the TotalMix group showed morphological changes possibly reflecting increased prolactin levels...

  4. The effect of caffeine on mammary gland development and milk yield in primiparous sows.

    Science.gov (United States)

    Li, S; Hacker, R R

    1995-02-01

    Pregnant Yorkshire gilts (n = 42) were fed caffeine (6 g/d) or served as controls from d 60 of pregnancy until d 4 postpartum to test the effect of caffeine on mammary gland development, milk yield, and feed consumption. Caffeine reduced voluntary feed intake (P = .001) and body weight gain (P = .001) of gilts from d 60 to 109 of gestation. Pig birth weight in the treated group was less than (P = .01) that in the control group. However, pig viability score at birth was not affected by maternal caffeine ingestion. For assessing mammary gland DNA, RNA, dry fat-free tissue (DFFT), fat, and protein content, four sows from the caffeine group and three controls were slaughtered on the 1st d of lactation. Immediately after slaughter, mammary systems were removed, separated by gland, and dissected free of skin, muscle, and fatty pad, which had not been invaded by glandular tissue. The DNA and RNA content were evaluated in DFFT. Caffeine increased mammary RNA content (P = .023) and milk yield (P = .001) on d 1 of lactation. However, DNA, DFFT, fat, and protein were not significantly increased, although values were somewhat greater in the treatment group (approximately 82%). On d 21 of lactation, milk yield of treated sows did not differ from that of controls. The increased milk yield on d 1 of lactation was due to increased mammary epithelial cell activity and cell numbers. These results indicate that caffeine feeding can have a positive effect on porcine mammary gland development as well as milk yield.

  5. Impaired Pten expression in human malignant peripheral nerve sheath tumours.

    Directory of Open Access Journals (Sweden)

    Maren Bradtmöller

    Full Text Available Malignant peripheral nerve sheath tumours (MPNST are aggressive sarcomas that develop in about 10% of patients with the genetic disease neurofibromatosis type 1 (NF1. Molecular alterations contributing to MPNST formation have only partially been resolved. Here we examined the role of Pten, a key regulator of the Pi3k/Akt/mTOR pathway, in human MPNST and benign neurofibromas. Immunohistochemistry showed that Pten expression was significantly lower in MPNST (n=16 than in neurofibromas (n=16 and normal nervous tissue. To elucidate potential mechanisms for Pten down-regulation or Akt/mTOR activation in MPNST we performed further experiments. Mutation analysis revealed absence of somatic mutations in PTEN (n=31 and PIK3CA (n=38. However, we found frequent PTEN promotor methylation in primary MPNST (11/26 and MPNST cell lines (7/8 but not in benign nerve sheath tumours. PTEN methylation was significantly associated with early metastasis. Moreover, we detected an inverse correlation of Pten-regulating miR-21 and Pten protein levels in MPNST cell lines. The examination of NF1-/- and NF1+/+Schwann cells and fibroblasts showed that Pten expression is not regulated by NF1. To determine the significance of Pten status for treatment with the mTOR inhibitor rapamycin we treated 5 MPNST cell lines with rapamycin. All cell lines were sensitive to rapamycin without a significant correlation to Pten levels. When rapamycin was combined with simvastatin a synergistic anti-proliferative effect was achieved. Taken together we show frequent loss/reduction of Pten expression in MPNST and provide evidence for the involvement of multiple Pten regulating mechanisms.

  6. Development of Foreign Mammary Epithelial Morphology in the Stroma of Immunodeficient Mice.

    Directory of Open Access Journals (Sweden)

    Gat Rauner

    Full Text Available Systemic growth and branching stimuli, and appropriate interactions with the host stroma are essential for the development of foreign epithelia in the mammary gland of immunodeficient mice. These factors were manipulated to promote and investigate the generation of representative bovine epithelial morphology in the transplanted mouse mammary stroma. The bovine mammary epithelium is unique in its commitment to rapid proliferation and high rate of differentiation. Its morphological organization within a fibrotic stroma resembles that of the human breast, and differs significantly from the rudimentary ductal network that penetrates a fatty stroma in mice. Transplantation of bovine mammary epithelial cells into the cleared mammary fat pad of NOD-SCID mice led to continuous growth of epithelial structures. Multilayered hollow spheres developed within fibrotic areas, but in contrast to mice, no epithelial organization was formed between adipocytes. The multilayered spheres shared characteristics with the heifer gland's epithelium, including lumen size, cell proliferation, cytokeratin orientation, estrogen/progesterone receptor expression and localization, and milk protein synthesis. However, they did not extend into the mouse fat pad via ductal morphology. Pre-transplantation of fibroblasts increased the number of spheres, but did not promote extension of bovine morphology. The bovine cells preserved their fate and rarely participated in chimeric mouse-bovine outgrowths. Nevertheless, a single case of terminal ductal lobuloalveolar unit (TDLU development was recorded in mice treated with estrogen and progesterone, implying the feasibility of this representative bovine morphology's development. In vitro extension of these studies revealed paracrine inhibition of bovine epithelial mammosphere development by adipocytes, which was also generalized to breast epithelial mammosphere formation. The rescue of mammosphere development by fibroblast growth factor

  7. Segregated responses of mammary gland development and vaginal opening to prepubertal genistein exposure in Bscl2(-/-) female mice with lipodystrophy.

    Science.gov (United States)

    Li, Rong; El Zowalaty, Ahmed E; Chen, Weiqin; Dudley, Elizabeth A; Ye, Xiaoqin

    2015-07-01

    Berardinelli-Seip congenital lipodystrophy 2-deficient (Bscl2(-/-)) mice recapitulate human BSCL2 disease with lipodystrophy. Bscl2-encoded seipin is detected in adipocytes and epithelium of mammary gland. Postnatal mammary gland growth spurt and vaginal opening signify pubertal onset in female mice. Bscl2(-/-) females have longer and dilated mammary gland ducts at 5-week old and delayed vaginal opening. Prepubertal exposure to 500ppm genistein diet increases mammary gland area and accelerates vaginal opening in both control and Bscl2(-/-) females. However, genistein treatment increases ductal length in control but not Bscl2(-/-) females. Neither prepubertal genistein treatment nor Bscl2-deficiency affects phospho-estrogen receptor α or progesterone receptor expression patterns in 5-week old mammary gland. Interestingly, Bscl2-deficiency specifically reduces estrogen receptor β expression in mammary gland ductal epithelium. In summary, Bscl2(-/-) females have accelerated postnatal mammary ductal development but delayed vaginal opening; they display segregated responses in mammary gland development and vaginal opening to prepubertal genistein treatment.

  8. Generation of a new bioluminescent model for visualisation of mammary tumour development in transgenic mice

    Directory of Open Access Journals (Sweden)

    Zagozdzon Agnieszka M

    2012-05-01

    Full Text Available Abstract Background Numerous transgenic models have been generated to study breast cancer. However, despite many advantages, traditional transgenic models for breast cancer are also burdened with difficulties in early detection and longitudinal observation of transgene-induced tumours, which in most cases are randomly located and occur at various time points. Methods such as palpation followed by mechanical measurement of the tumours are of limited value in transgenic models. There is a crucial need for making these previously generated models suitable for modern methods of tumour visualisation and monitoring, e.g. by bioluminescence-based techniques. This approach was successfully used in the current study. Results A new mouse strain (MMTV-Luc2 mice expressing Luc2 luciferase primarily in mammary tissue in females, with low-level background expression in internal organs, was generated and bred to homozygosity. After these mice were intercrossed with MMTV-PyVT mice, all double transgenic females developed mammary tumours by the age of 10 weeks, the localisation and progression of which could be effectively monitored using the luminescence-based in vivo imaging. Luminescence-based readout allowed for early visualisation of the locally overgrown mammary tissue and for longitudinal evaluation of local progression of the tumours. When sampled ex vivo at the age of 10 weeks, all tumours derived from MMTV-Luc2PyVT females displayed robust bioluminescent signal. Conclusions We have created a novel transgenic strain for visualisation and longitudinal monitoring of mammary tumour development in transgenic mice as an addition and/or a new and more advanced alternative to manual methods. Generation of this mouse strain is vital for making many of the existing mammary tumour transgenic models applicable for in vivo imaging techniques.

  9. Generation of a new bioluminescent model for visualisation of mammary tumour development in transgenic mice

    LENUS (Irish Health Repository)

    Zagozdzon, Agnieszka M

    2012-05-30

    AbstractBackgroundNumerous transgenic models have been generated to study breast cancer. However, despite many advantages, traditional transgenic models for breast cancer are also burdened with difficulties in early detection and longitudinal observation of transgene-induced tumours, which in most cases are randomly located and occur at various time points. Methods such as palpation followed by mechanical measurement of the tumours are of limited value in transgenic models. There is a crucial need for making these previously generated models suitable for modern methods of tumour visualisation and monitoring, e.g. by bioluminescence-based techniques. This approach was successfully used in the current study.ResultsA new mouse strain (MMTV-Luc2 mice) expressing Luc2 luciferase primarily in mammary tissue in females, with low-level background expression in internal organs, was generated and bred to homozygosity. After these mice were intercrossed with MMTV-PyVT mice, all double transgenic females developed mammary tumours by the age of 10 weeks, the localisation and progression of which could be effectively monitored using the luminescence-based in vivo imaging. Luminescence-based readout allowed for early visualisation of the locally overgrown mammary tissue and for longitudinal evaluation of local progression of the tumours. When sampled ex vivo at the age of 10 weeks, all tumours derived from MMTV-Luc2PyVT females displayed robust bioluminescent signal.ConclusionsWe have created a novel transgenic strain for visualisation and longitudinal monitoring of mammary tumour development in transgenic mice as an addition and\\/or a new and more advanced alternative to manual methods. Generation of this mouse strain is vital for making many of the existing mammary tumour transgenic models applicable for in vivo imaging techniques.

  10. PTEN Interacts with Histone H1 and Controls Chromatin Condensation

    Directory of Open Access Journals (Sweden)

    Zhu Hong Chen

    2014-09-01

    Full Text Available Chromatin organization and dynamics are integral to global gene transcription. Histone modification influences chromatin status and gene expression. PTEN plays multiple roles in tumor suppression, development, and metabolism. Here, we report on the interplay of PTEN, histone H1, and chromatin. We show that loss of PTEN leads to dissociation of histone H1 from chromatin and decondensation of chromatin. PTEN deletion also results in elevation of histone H4 acetylation at lysine 16, an epigenetic marker for chromatin activation. We found that PTEN and histone H1 physically interact through their C-terminal domains. Disruption of the PTEN C terminus promotes the chromatin association of MOF acetyltransferase and induces H4K16 acetylation. Hyperacetylation of H4K16 impairs the association of PTEN with histone H1, which constitutes regulatory feedback that may reduce chromatin stability. Our results demonstrate that PTEN controls chromatin condensation, thus influencing gene expression. We propose that PTEN regulates global gene transcription profiling through histones and chromatin remodeling.

  11. PTEN Gene: A Model for Genetic Diseases in Dermatology

    Directory of Open Access Journals (Sweden)

    Corrado Romano

    2012-01-01

    Full Text Available PTEN gene is considered one of the most mutated tumor suppressor genes in human cancer, and it’s likely to become the first one in the near future. Since 1997, its involvement in tumor suppression has smoothly increased, up to the current importance. Germline mutations of PTEN cause the PTEN hamartoma tumor syndrome (PHTS, which include the past-called Cowden, Bannayan-Riley-Ruvalcaba, Proteus, Proteus-like, and Lhermitte-Duclos syndromes. Somatic mutations of PTEN have been observed in glioblastoma, prostate cancer, and brest cancer cell lines, quoting only the first tissues where the involvement has been proven. The negative regulation of cell interactions with the extracellular matrix could be the way PTEN phosphatase acts as a tumor suppressor. PTEN gene plays an essential role in human development. A recent model sees PTEN function as a stepwise gradation, which can be impaired not only by heterozygous mutations and homozygous losses, but also by other molecular mechanisms, such as transcriptional regression, epigenetic silencing, regulation by microRNAs, posttranslational modification, and aberrant localization. The involvement of PTEN function in melanoma and multistage skin carcinogenesis, with its implication in cancer treatment, and the role of front office in diagnosing PHTS are the main reasons why the dermatologist should know about PTEN.

  12. Flor-Essence? Herbal Tonic Promotes Mammary Tumor Development in Sprague Dawley Rats

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, L; Montgomery, J; Steinberg, S; Kulp, K

    2004-01-28

    Background: Women who are diagnosed with breast cancer often self-administer complementary and alternative medicines to augment their conventional treatments, improve health, or prevent recurrence. Flor-Essence{reg_sign} Tonic is a complex mixture of herbal extracts used by cancer patients because of anecdotal evidence that it can treat or prevent disease. Methods: Female Sprague Dawley rats were given water or exposed to 3% or 6% Flor-Essence{reg_sign} beginning at one day of age. Mammary tumors were induced with a single oral 40 mg/kg/bw dose of dimethylbenz(a)anthracene at 50 days of age and sacrificed at 23 weeks. Rats were maintained on AIN-76A diet. Results: Control rats had palpable mammary tumor incidence of 51.0% at 19 weeks of age compared to 65.0% and 59.4% for the 3% and 6% Flor-Essence{reg_sign} groups respectively. Overall, no significant difference in time until first palpable tumor was detected among any of the groups. At necropsy, mammary tumor incidence was 82.5% for controls compared to 90.0% and 97.3% for rats consuming 3% and 6% Flor-Essence{reg_sign}, respectively. Mean mammary tumor multiplicity ({+-}SES) for the controls was 2.8 ({+-} 0.5) and statistically different from the 3% or 6% Flor- Essence{reg_sign} groups with 5.2 ({+-} 0.7), and 4.8 ({+-} 0.6), respectively (p{<=}0.01). As expected, the majority of isolated tumors were diagnosed as adenocarcinomas. Conclusions: Flor-Essence{reg_sign} can promote mammary tumor development in the Sprague Dawley rat model. This observation is contrary to widely available anecdotal evidence as well as the desire of the consumer that this commercially available herbal tonic will suppress and/or inhibit tumor growth.

  13. Modulation of Mammary Gland Development and Milk Production by Growth Hormone Expression in GH Transgenic Goats.

    Science.gov (United States)

    Bao, Zekun; Lin, Jian; Ye, Lulu; Zhang, Qiang; Chen, Jianquan; Yang, Qian; Yu, Qinghua

    2016-01-01

    Mammary gland development during puberty and reconstruction during pregnancy and lactation is under the control of circulating endocrine hormones, such as growth hormone, which are released from the pituitary. In this study, we explored the influence of overexpression of growth hormone in the mammary gland on breast development and milk production in goats. Using transcriptome sequencing, we found that the number of highly expressed genes was greater in GH transgenic goats than non-transgenic goats. Furthermore, KEGG pathway analysis showed that the majority of the genes belonged to the MAPK signaling pathway and the ECM-receptor interaction pathway. The expression of genes related to breast development was further confirmed using qRT-PCR. Interestingly, both milk production and milk quality were increased. The results of these experiments imply that overexpression of growth hormone in the breast may stimulate breast development and enhances milk production by modulating alveolar cell proliferation or branching through the MAPK signaling pathway.

  14. Identification of nucleolus-localized PTEN and its function in regulating ribosome biogenesis.

    Science.gov (United States)

    Li, Pingdong; Wang, Danni; Li, Haiyang; Yu, Zhenkun; Chen, Xiaohong; Fang, Jugao

    2014-10-01

    The tumor suppressor PTEN is a lipid phosphatase that is found mutated in different types of human cancers. PTEN suppresses cell proliferation by inhibiting the PI3K-Akt signaling pathway at the cell membrane. However, PTEN is also demonstrated to localize in the cell nucleus where it exhibits tumor suppressive activity via a different, unknown mechanism. In this study we report that PTEN also localizes to the nucleolus and that nucleolar PTEN plays an important role in regulating nucleolar homeostasis and maintaining nucleolar morphology. Overexpression of nuclear PTEN in PTEN null cells inhibits Akt phosphorylation and reduces cell size. Knockdown of PTEN in PTEN positive cells leads to nucleolar morphologic changes and an increase in the proportion of cells with a greater number of nucleoli. In addition, knockdown of PTEN in PTEN positive cells increased ribosome biogenesis. These findings expand current understanding of function and relevance of nuclear localized PTEN and provide a foundation for the development of novel therapies targeting PTEN.

  15. Twisted Gastrulation as a BMP Modulator during Mammary Gland Development and Tumorigenesis

    Science.gov (United States)

    2014-05-01

    preplacodal ectoderm specification (Kwon et al., 2010), and hair follicle morphogenesis (Kobielak et al., 2003). In the MG, GATA-3 deficiency...BMP4 and PTHrP interact to stimulate ductal outgrowth during embryonic mammary development and to inhibit hair follicle induction. Development. 2007...pubertal duct cDNA we measured a significant reduction in downstream targets such as Id-2, Msx1, Msx2 and Gata-3 in the Twsg1-/- MG (Appendix 1

  16. PTEN: a default gate-keeping tumor suppressor with a versatile tail

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The tumor suppressor PTEN controls a variety of biological processes including cell proliferation, growth, migration, and death. As a master cellular regulator, PTEN itself is also subjected to deliberated regulation to ensure its proper function. Defects in PTEN regulation have a profound impact on carcinogenesis. In this review, we briefly discuss recent advances concerning PTEN regulation and how such knowledge facilitates our understanding and further exploration of PTEN biology. The carboxyl-tail of PTEN, which appears to be associated with multiple types of posttranslational regulation, will be under detailed scrutiny. Further, a comparative analysis of PTEN and p53 suggests while p53 needs to be activated to suppress tumorigenesis (a dormant gatekeeper), PTEN is probably a constitutive surveillant against cancer development, thus a default gatekeeper.

  17. Macrophages: Regulators of the Inflammatory Microenvironment during Mammary Gland Development and Breast Cancer.

    Science.gov (United States)

    Brady, Nicholas J; Chuntova, Pavlina; Schwertfeger, Kathryn L

    2016-01-01

    Macrophages are critical mediators of inflammation and important regulators of developmental processes. As a key phagocytic cell type, macrophages evolved as part of the innate immune system to engulf and process cell debris and pathogens. Macrophages produce factors that act directly on their microenvironment and also bridge innate immune responses to the adaptive immune system. Resident macrophages are important for acting as sensors for tissue damage and maintaining tissue homeostasis. It is now well-established that macrophages are an integral component of the breast tumor microenvironment, where they contribute to tumor growth and progression, likely through many of the mechanisms that are utilized during normal wound healing responses. Because macrophages contribute to normal mammary gland development and breast cancer growth and progression, this review will discuss both resident mammary gland macrophages and tumor-associated macrophages with an emphasis on describing how macrophages interact with their surrounding environment during normal development and in the context of cancer.

  18. Pten function in zebrafish : Anything but a fish story

    NARCIS (Netherlands)

    Stumpf, Miriam; Choorapoikayil, Suma; den Hertog, J.

    2015-01-01

    Zebrafish is an excellent model system for the analysis of gene function. We and others use zebrafish to investigate the function of the tumor suppressor, Pten, in tumorigenesis and embryonic development. Zebrafish have two pten genes, ptena and ptenb. The recently identified N-terminal extension of

  19. Abnormal Mammary Development in 129:STAT1-Null Mice is Stroma-Dependent.

    Science.gov (United States)

    Chen, Jane Q; Mori, Hidetoshi; Cardiff, Robert D; Trott, Josephine F; Hovey, Russell C; Hubbard, Neil E; Engelberg, Jesse A; Tepper, Clifford G; Willis, Brandon J; Khan, Imran H; Ravindran, Resmi K; Chan, Szeman R; Schreiber, Robert D; Borowsky, Alexander D

    2015-01-01

    Female 129:Stat1-null mice (129S6/SvEvTac-Stat1(tm1Rds) homozygous) uniquely develop estrogen-receptor (ER)-positive mammary tumors. Herein we report that the mammary glands (MG) of these mice have altered growth and development with abnormal terminal end buds alongside defective branching morphogenesis and ductal elongation. We also find that the 129:Stat1-null mammary fat pad (MFP) fails to sustain the growth of 129S6/SvEv wild-type and Stat1-null epithelium. These abnormalities are partially reversed by elevated serum progesterone and prolactin whereas transplantation of wild-type bone marrow into 129:Stat1-null mice does not reverse the MG developmental defects. Medium conditioned by 129:Stat1-null epithelium-cleared MFP does not stimulate epithelial proliferation, whereas it is stimulated by medium conditioned by epithelium-cleared MFP from either wild-type or 129:Stat1-null females having elevated progesterone and prolactin. Microarrays and multiplexed cytokine assays reveal that the MG of 129:Stat1-null mice has lower levels of growth factors that have been implicated in normal MG growth and development. Transplanted 129:Stat1-null tumors and their isolated cells also grow slower in 129:Stat1-null MG compared to wild-type recipient MG. These studies demonstrate that growth of normal and neoplastic 129:Stat1-null epithelium is dependent on the hormonal milieu and on factors from the mammary stroma such as cytokines. While the individual or combined effects of these factors remains to be resolved, our data supports the role of STAT1 in maintaining a tumor-suppressive MG microenvironment.

  20. The T-box transcription factors TBX2 and TBX3 in mammary gland development and breast cancer.

    Science.gov (United States)

    Douglas, Nataki C; Papaioannou, Virginia E

    2013-06-01

    TBX2 and TBX3, closely related members of the T-box family of transcription factor genes, are expressed in mammary tissue in both humans and mice. Ulnar mammary syndrome (UMS), an autosomal dominant disorder caused by mutations in TBX3, underscores the importance of TBX3 in human breast development, while abnormal mammary gland development in Tbx2 or Tbx3 mutant mice provides models for experimental investigation. In addition to their roles in mammary development, aberrant expression of TBX2 and TBX3 is associated with breast cancer. TBX2 is preferentially amplified in BRCA1/2-associated breast cancers and TBX3 overexpression has been associated with advanced stage disease and estrogen-receptor-positive breast tumors. The regulation of Tbx2 and Tbx3 and the downstream targets of these genes in development and disease are not as yet fully elucidated. However, it is clear that the two genes play unique, context-dependent roles both in mammary gland development and in mammary tumorigenesis.

  1. The role of the microenvironment in mammary gland development and cancer.

    Science.gov (United States)

    Polyak, Kornelia; Kalluri, Raghu

    2010-11-01

    The mammary gland is composed of a diverse array of cell types that form intricate interaction networks essential for its normal development and physiologic function. Abnormalities in these interactions play an important role throughout different stages of tumorigenesis. Branching ducts and alveoli are lined by an inner layer of secretory luminal epithelial cells that produce milk during lactation and are surrounded by contractile myoepithelial cells and basement membrane. The surrounding stroma comprised of extracellular matrix and various cell types including fibroblasts, endothelial cells, and infiltrating leukocytes not only provides a scaffold for the organ, but also regulates mammary epithelial cell function via paracrine, physical, and hormonal interactions. With rare exceptions breast tumors initiate in the epithelial compartment and in their initial phases are confined to the ducts but this barrier brakes down with invasive progression because of a combination of signals emitted by tumor epithelial and various stromal cells. In this article, we overview the importance of cellular interactions and microenvironmental signals in mammary gland development and cancer.

  2. ErbB/EGF signaling and EMT in mammary development and breast cancer.

    Science.gov (United States)

    Hardy, Katharine M; Booth, Brian W; Hendrix, Mary J C; Salomon, David S; Strizzi, Luigi

    2010-06-01

    Activation of the ErbB family of receptor tyrosine kinases via cognate Epidermal Growth Factor (EGF)-like peptide ligands constitutes a major group of related signaling pathways that control proliferation, survival, angiogenesis and metastasis of breast cancer. In this respect, clinical trials with various ErbB receptor blocking antibodies and specific tyrosine kinase inhibitors have proven to be partially efficacious in the treatment of this heterogeneous disease. Induction of an embryonic program of epithelial-to-mesenchymal transition (EMT) in breast cancer, whereupon epithelial tumor cells convert to a more mesenchymal-like phenotype, facilitates the migration, intravasation, and extravasation of tumor cells during metastasis. Breast cancers which exhibit properties of EMT are highly aggressive and resistant to therapy. Activation of ErbB signaling can regulate EMT-associated invasion and migration in normal and malignant mammary epithelial cells, as well as modulating discrete stages of mammary gland development. The purpose of this review is to summarize current information regarding the role of ErbB signaling in aspects of EMT that influence epithelial cell plasticity during mammary gland development and tumorigenesis. How this information may contribute to the improvement of therapeutic approaches in breast cancer will also be addressed.

  3. Stromal regulation of embryonic and postnatal mammary epithelial development and differentiation.

    Science.gov (United States)

    Howard, Beatrice A; Lu, Pengfei

    2014-01-01

    The stroma, which is composed of supporting cells and connective tissue, comprises a large component of the local microenvironment of many epithelial cell types, and influences several fundamental aspects of cell behaviour through both tissue interactions and niche regulation. The significance of the stroma in development and disease has been increasingly recognised. Whereas normal stroma is essential for various developmental processes during vertebrate organogenesis, it can be deregulated and become abnormal, which in turn can initiate or promote a disease process, including cancer. The mouse mammary gland has emerged in recent years as an excellent model system for understanding stromal function in both developmental and cancer biology. Here, we take a systematic approach and focus on the dynamic interactions that the stroma engages with the epithelium during mammary specification, cell differentiation, and branching morphogenesis of both the embryonic and postnatal development of the mammary gland. Similar stromal-epithelial interactions underlie the aetiology of breast cancer, making targeting the cancer stroma an increasingly important and promising therapeutic strategy to pursue for breast cancer treatment.

  4. Gpr177 deficiency impairs mammary development and prohibits Wnt-induced tumorigenesis.

    Science.gov (United States)

    Maruyama, Eri Ohfuchi; Yu, H-M Ivy; Jiang, Ming; Fu, Jiang; Hsu, Wei

    2013-01-01

    Aberrant regulation of the Wnt pathway, essential for various developmental processes, is tightly linked to human breast cancers. By hijacking this evolutionary conserved signaling pathway, cancer cells acquire sustaining proliferation ability, leading to modification of physiologic properties necessary for tumor initiation and progression. An enormous wealth of knowledge on the importance of Wnt signaling in breast development and cancer has been obtained, but the cell types responsible for production of this proliferative signal operating within normal and malignant tissues remains poorly understood. Here we report that Wnt production mediated by Gpr177 is essential for mammary morphogenesis. The loss of Gpr177 interferes with mammary stem cells, leading to deficiencies in cell proliferation and differentiation. Genetic analysis further demonstrates an indispensable role of Gpr177 in Wnt-induced tumorigenesis. The Gpr177-deficiency mice are resistant to malignant transformation. This study not only demonstrates the necessity of Wnt in mammary organogenesis but also provides a proof-of-principle for targeting of Gpr177 as a potential new treatment for human diseases with aberrant Wnt stimulation.

  5. Gpr177 deficiency impairs mammary development and prohibits Wnt-induced tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Eri Ohfuchi Maruyama

    Full Text Available Aberrant regulation of the Wnt pathway, essential for various developmental processes, is tightly linked to human breast cancers. By hijacking this evolutionary conserved signaling pathway, cancer cells acquire sustaining proliferation ability, leading to modification of physiologic properties necessary for tumor initiation and progression. An enormous wealth of knowledge on the importance of Wnt signaling in breast development and cancer has been obtained, but the cell types responsible for production of this proliferative signal operating within normal and malignant tissues remains poorly understood. Here we report that Wnt production mediated by Gpr177 is essential for mammary morphogenesis. The loss of Gpr177 interferes with mammary stem cells, leading to deficiencies in cell proliferation and differentiation. Genetic analysis further demonstrates an indispensable role of Gpr177 in Wnt-induced tumorigenesis. The Gpr177-deficiency mice are resistant to malignant transformation. This study not only demonstrates the necessity of Wnt in mammary organogenesis but also provides a proof-of-principle for targeting of Gpr177 as a potential new treatment for human diseases with aberrant Wnt stimulation.

  6. Modulation of mammary gland development in prepubertal male rats exposed to genistein and methoxychlor.

    Science.gov (United States)

    You, Li; Sar, Madhabananda; Bartolucci, Erika J; McIntyre, Barry S; Sriperumbudur, Rajagopal

    2002-04-01

    The estrogenic isoflavone genistein is a common dietary component that has been shown to affect reproductive development in experimental animals at high doses. The objective of the present study was to examine interactions of genistein and the hormonally active pesticide methoxychlor on mammary gland development in juvenile rats. Timed-pregnant Sprague-Dawley rats were fed a soy- and alfalfa-free diet containing different combinations of genistein (300 and 800 ppm) and methoxychlor (800 ppm). Rats were fed these diets starting on gestation day (GD)1 and continuing through pregnancy and lactation until postnatal day (PND) 22, when the pups were killed. Inguinal mammary glands from both female and male pups were processed as whole-mount preparations for morphometric analysis. The total glandular area and the numbers of branch points, lateral buds, and terminal end buds in the male rats were found to be significantly greater in the groups exposed to methoxychlor than those exposed to genistein only. These effects were not observed in the female rats. In the male rats, methoxychlor had the most prominent effect on elongating the glandular ducts, while genistein enhanced the ductile branching. The 2 compounds in combination promoted the development of alveolar-lobular structure, an effect not observed with either compound alone. Immunostaining for proliferating cell nuclear antigen revealed a high percentage of immunopositive cells in the mammary epithelia of the males exposed to methoxychlor and genistein (800 ppm) compared to the controls. While no significant changes in serum levels of mammotrophic hormones were detected, increased immunostaining for insulin-like growth factor-1 receptor, estrogen receptor alpha, and progesterone receptor in the genistein + methoxychlor group suggested that local factors involved in regulating mammary growth may have played a role in propagating the endocrine effects of these two compounds. These results indicated that the mammary

  7. Differential Mammary Gland Development in FVB and C57Bl/6 Mice: Implications for Breast Cancer Research

    Directory of Open Access Journals (Sweden)

    Breanne M. Anderson

    2011-10-01

    Full Text Available A growing body of research suggests a linkage between pubertal mammary gland development and environmental factors such as diet as modifiers of long term breast cancer risk. Much of this research is dependent upon mouse models, which may vary between studies. However, effects may be strain dependent and further modified by diet, which has not been previously examined. Therefore, the objective of the present study was to determine whether mammary gland development differs between FVB and C57Bl/6 strains on diets containing either n-6 or n-3 polyunsaturated fats. Developmental measures related to onset of puberty and mammary gland development differed between strains. Mice fed the n-3 polyunsaturated fatty acids (PUFA diet were shown to have lower numbers of terminal end buds, a marker of mammary gland development. This study helps to further clarify differences in development and dietary response between FVB and C57Bl/6 mice in order to more appropriately relate mammary gland research to human populations.

  8. Akt1 is essential for postnatal mammary gland development, function, and the expression of Btn1a1.

    Directory of Open Access Journals (Sweden)

    Jessica LaRocca

    Full Text Available Akt1, a serine-threonine protein kinase member of the PKB/Akt gene family, plays critical roles in the regulation of multiple cellular processes, and has previously been implicated in lactation and breast cancer development. In this study, we utilized Akt1+/+ and Akt1-/- C57/Bl6 female mice to assess the role that Akt1 plays in normal mammary gland postnatal development and function. We examined postnatal morphology at multiple time points, and analyzed gene and protein expression changes that persist into adulthood. Akt1 deficiency resulted in several mammary gland developmental defects, including ductal outgrowth and defective terminal end bud formation. Adult Akt1-/- mammary gland composition remained altered, exhibiting fewer alveolar buds coupled with increased epithelial cell apoptosis. Microarray analysis revealed that Akt1 deficiency altered expression of genes involved in numerous biological processes in the mammary gland, including organismal development, cell death, and tissue morphology. Of particular importance, a significant decrease in expression of Btn1a1, a gene involved in milk lipid secretion, was observed in Akt1-/- mammary glands. Additionally, pseudopregnant Akt1-/- females failed to induce Btn1a1 expression in response to hormonal stimulation compared to their wild-type counterparts. Retroviral-mediated shRNA knockdown of Akt1 and Btn1a1 in MCF-7 human breast epithelial further illustrated the importance of Akt1 in mammary epithelial cell proliferation, as well as in the regulation of Btn1a1 and subsequent expression of ß-casein, a gene that encodes for milk protein. Overall these findings provide mechanistic insight into the role of Akt1 in mammary morphogenesis and function.

  9. Mammary carcinoma diagnostics and therapy; Diagnostik und Therapie des Mammakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Uwe; Baum, Friedemann (eds.) [Diagnostisches Brustzentrum Goettingen BZG, Goettingen(Germany)

    2014-11-01

    The book on mammary carcinoma diagnostics and therapy covers the following issues: development, anatomy and physiology of the mammary glands, pathology of benign and malign mammary gland changes, non-imaging diagnostics; mammography; ultrasonic mammography; magnetic resonance tomography of the mammary glands; imaging diagnostics findings; mammary interventions; examination concepts; operative therapy of the mammary carcinoma; chemotherapy of the mammary carcinoma; radio-oncological therapy of the mammary carcinoma; logistics in a medical center for mammary gland diseases; logistics in an interdisciplinary center for mammary diseases; dialogue conduction and psycho-social attendance.

  10. A Novel Nectin-mediated Cell Adhesion Apparatus That Is Implicated in Prolactin Receptor Signaling for Mammary Gland Development.

    Science.gov (United States)

    Kitayama, Midori; Mizutani, Kiyohito; Maruoka, Masahiro; Mandai, Kenji; Sakakibara, Shotaro; Ueda, Yuki; Komori, Takahide; Shimono, Yohei; Takai, Yoshimi

    2016-03-11

    Mammary gland development is induced by the actions of various hormones to form a structure consisting of collecting ducts and milk-secreting alveoli, which comprise two types of epithelial cells known as luminal and basal cells. These cells adhere to each other by cell adhesion apparatuses whose roles in hormone-dependent mammary gland development remain largely unknown. Here we identified a novel cell adhesion apparatus at the boundary between the luminal and basal cells in addition to desmosomes. This apparatus was formed by the trans-interaction between the cell adhesion molecules nectin-4 and nectin-1, which were expressed in the luminal and basal cells, respectively. Nectin-4 of this apparatus further cis-interacted with the prolactin receptor in the luminal cells to enhance the prolactin-induced prolactin receptor signaling for alveolar development with lactogenic differentiation. Thus, a novel nectin-mediated cell adhesion apparatus regulates the prolactin receptor signaling for mammary gland development.

  11. Subcellular targeting and dynamic regulation of PTEN: Implications for neuronal cells and neurological disorders

    Directory of Open Access Journals (Sweden)

    Patricia eKreis

    2014-04-01

    Full Text Available PTEN is a lipid and protein phosphatase that regulates a diverse range of cellular mechanisms. PTEN is mainly present in the cytosol and transiently associates with the plasma membrane to dephosphorylate PI(3,4,5P3, thereby antagonizing the PI3-Kinase signaling pathway. Recently, PTEN has been shown to associate also with organelles such as the endoplasmic reticulum, the mitochondria or the nucleus, and to be secreted outside of the cell. In addition, PTEN dynamically localizes to specialized sub-cellular compartments such as the neuronal growth cone or dendritic spines. The diverse localizations of PTEN imply a tight temporal and spatial regulation, orchestrated by mechanisms such as posttranslational modifications, formation of distinct protein-protein interactions or the activation/recruitment of PTEN downstream of external cues. The regulation of PTEN function is thus not only important at the enzymatic activity level, but is also associated to its spatial distribution. In this review we will summarize (i recent findings that highlight mechanisms controlling PTEN movement and sub-cellular localization, and (ii current understanding of how PTEN localization is achieved by mechanisms controlling posttranslational modification, by association with binding partners and by PTEN structural or activity requirements. Finally, we will discuss the possible roles of compartmentalized PTEN in developing and mature neurons in health and disease.

  12. Influence of prevastein (R), an isoflavone-rich soy product, on mammary gland development and Tumorigenesis in Tg.NK (MMTV/c-neu) mice

    DEFF Research Database (Denmark)

    Thomsen, Anni R.; Mortensen, Alicja; Breinholt, Vibeke

    2005-01-01

    to controls (P actively dividing cells within the TEBs was unaffected by isoflavone exposure as was the activity of drug-metabolizing and antioxidant enzymes. In conclusion, isoflavones may augment mammary gland and mammary tumor development....... of isoflavones was associated with a small but significant increase in the number and size of tumors as compared to mice administered a Western-style control diet (P activity (measured as apoptotic density) at the highest dose and the degree of branching of the mammary tree...

  13. Loss of the heparan sulfate sulfotransferase, Ndst1, in mammary epithelial cells selectively blocks lobuloalveolar development in mice.

    Directory of Open Access Journals (Sweden)

    Brett E Crawford

    Full Text Available BACKGROUND: Considerable evidence indicates that heparan sulfate is essential for the development of tissues consisting of branching ducts and tubules. However, there are few examples where specific sulfate residues regulate a specific stage in the formation of such tissues. METHODOLOGY/PRINCIPAL FINDINGS: We examined the role of heparan sulfation in mammary gland branching morphogenesis, lactation and lobuloalveolar development by inactivation of heparan sulfate GlcNAc N-deacetylase/N-sulfotransferase genes (Ndst in mammary epithelial cells using the Cre-loxP system. Ndst1 deficiency resulted in an overall reduction in glucosamine N-sulfation and decreased binding of FGF to mammary epithelial cells in vitro and in vivo. Mammary epithelia lacking Ndst1 underwent branching morphogenesis, filling the gland with ductal tissue by sexual maturity to the same extent as wildtype epithelia. However, lobuloalveolar expansion did not occur in Ndst1-deficient animals, resulting in insufficient milk production to nurture newly born pups. Lactational differentiation of isolated mammary epithelial cells occurred appropriately via stat5 activation, further supporting the notion that the lack of milk production was due to lack of expansion of the lobuloalveoli. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate a selective, highly penetrant, cell autonomous effect of Ndst1-mediated sulfation on lobuloalveolar development.

  14. Comparative expression pathway analysis of human and canine mammary tumors

    Directory of Open Access Journals (Sweden)

    Marconato Laura

    2009-03-01

    Full Text Available Abstract Background Spontaneous tumors in dog have been demonstrated to share many features with their human counterparts, including relevant molecular targets, histological appearance, genetics, biological behavior and response to conventional treatments. Mammary tumors in dog therefore provide an attractive alternative to more classical mouse models, such as transgenics or xenografts, where the tumour is artificially induced. To assess the extent to which dog tumors represent clinically significant human phenotypes, we performed the first genome-wide comparative analysis of transcriptional changes occurring in mammary tumors of the two species, with particular focus on the molecular pathways involved. Results We analyzed human and dog gene expression data derived from both tumor and normal mammary samples. By analyzing the expression levels of about ten thousand dog/human orthologous genes we observed a significant overlap of genes deregulated in the mammary tumor samples, as compared to their normal counterparts. Pathway analysis of gene expression data revealed a great degree of similarity in the perturbation of many cancer-related pathways, including the 'PI3K/AKT', 'KRAS', 'PTEN', 'WNT-beta catenin' and 'MAPK cascade'. Moreover, we show that the transcriptional relationships between different gene signatures observed in human breast cancer are largely maintained in the canine model, suggesting a close interspecies similarity in the network of cancer signalling circuitries. Conclusion Our data confirm and further strengthen the value of the canine mammary cancer model and open up new perspectives for the evaluation of novel cancer therapeutics and the development of prognostic and diagnostic biomarkers to be used in clinical studies.

  15. Mesodermal Pten inactivation leads to alveolar capillary dysplasia- like phenotype.

    Science.gov (United States)

    Tiozzo, Caterina; Carraro, Gianni; Al Alam, Denise; Baptista, Sheryl; Danopoulos, Soula; Li, Aimin; Lavarreda-Pearce, Maria; Li, Changgong; De Langhe, Stijn; Chan, Belinda; Borok, Zea; Bellusci, Saverio; Minoo, Parviz

    2012-11-01

    Alveolar capillary dysplasia (ACD) is a congenital, lethal disorder of the pulmonary vasculature. Phosphatase and tensin homologue deleted from chromosome 10 (Pten) encodes a lipid phosphatase controlling key cellular functions, including stem/progenitor cell proliferation and differentiation; however, the role of PTEN in mesodermal lung cell lineage formation remains unexamined. To determine the role of mesodermal PTEN in the ontogeny of various mesenchymal cell lineages during lung development, we specifically deleted Pten in early embryonic lung mesenchyme in mice. Pups lacking Pten died at birth, with evidence of failure in blood oxygenation. Analysis at the cellular level showed defects in angioblast differentiation to endothelial cells and an accompanying accumulation of the angioblast cell population that was associated with disorganized capillary beds. We also found decreased expression of Forkhead box protein F1 (Foxf1), a gene associated with the ACD human phenotype. Analysis of human samples for ACD revealed a significant decrease in PTEN and increased activated protein kinase B (AKT). These studies demonstrate that mesodermal PTEN has a key role in controlling the amplification of angioblasts as well as their differentiation into endothelial cells, thereby directing the establishment of a functional gas exchange interface. Additionally, these mice could serve as a murine model of ACD.

  16. Characterization of a novel PTEN mutation in MDA-MB-453 breast carcinoma cell line

    Directory of Open Access Journals (Sweden)

    Singh Gobind

    2011-11-01

    Full Text Available Abstract Background Cowden Syndrome (CS patients with germ line point mutations in the PTEN gene are at high risk for developing breast cancer. It is believed that cells harboring these mutant PTEN alleles are predisposed to malignant conversion. This article will characterize the biochemical and biological properties of a mutant PTEN protein found in a commonly used metastatic breast cancer cell line. Methods The expression of PTEN in human breast carcinoma cell lines was evaluated by Western blotting analysis. Cell line MDA-MB-453 was selected for further analysis. Mutation analysis of the PTEN gene was carried out using DNA isolated from MDA-MB-453. Site-directed mutagenesis was used to generate a PTEN E307K mutant cDNA and ectopic expressed in PC3, U87MG, MCF7 and Pten-/- mouse embryo fibroblasts (MEFS. Histidine (His-tagged PTEN fusion protein was generated in Sf9 baculovirus expression system. Lipid phosphatase and ubiquitination assays were carried out to characterize the biochemical properties of PTEN E307K mutant. The intracellular localization of PTEN E307K was determined by subcellular fractionation experiments. The ability of PTEN E307K to alter cell growth, migration and apoptosis was analyzed in multiple PTEN-null cell lines. Results We found a mutation in the PTEN gene at codon 307 in MDA-MB-453 cell line. The glutamate (E to lysine (K substitution rendered the mutant protein to migrate with a faster mobility on SDS-PAGE gels. Biochemically, the PTEN E307K mutant displayed similar lipid phosphatase and growth suppressing activities when compared to wild-type (WT protein. However, the PTEN E307K mutant was present at higher levels in the membrane fraction and suppressed Akt activation to a greater extent than the WT protein. Additionally, the PTEN E307K mutant was polyubiquitinated to a greater extent by NEDD4-1 and displayed reduced nuclear localization. Finally, the PTEN E307K mutant failed to confer chemosensitivity to

  17. Development of Hyperplasias, Preneoplasias, and Mammary Tumors in MMTV-c-erbB-2 and MMTV-TGFα Transgenic Rats

    Science.gov (United States)

    Davies, Barry R.; Platt-Higgins, Angela M.; Schmidt, Gunter; Rudland, Philip S.

    1999-01-01

    Human cDNAs corresponding to two epidermal growth factor-related products that are overexpressed in human breast cancers, that for c-erbB-2 (HER-2) and for transforming growth factor α (TGFα), have been cloned downstream of the mouse mammary tumor virus (MMTV) long terminal repeat promoter and injected into the pronucleus of fertilized oocytes of Sprague-Dawley rats to produce transgenic offspring. Expression of the transgenic mRNAs is not detectable in mammary tissue from virgin transgenic rats but is detected in mammary tissue from certain lines of mid-pregnant transgenic rats. When two such lines of either type of transgenic rat are subjected to repeated cycles of pregnancy and lactation, they produce, primarily in the mammary glands, extensive pathologies, whereas virgin transgenic rats produce no such abnormalities. Multiparous transgenic female offspring from c-erbB-2-expressing lines develop a variety of focal hyperplastic and benign lesions that resemble lesions commonly found in human breasts. These lesions include lobular and ductal hyperplasia, fibroadenoma, cystic expansions, and papillary adenomas. More malignant lesions, including ductal carcinoma in situ and carcinoma, also develop stochastically at low frequency. The mammary glands of transgenic females invariably fail to involute fully after lactation. Similar phenotypes are observed in female MMTV-TGFα transgenic rats. In addition, multiparous TGFα-expressing female transgenics frequently develop severe pregnancy-dependent lactating hyperplasias as well as residual lobules of hyperplastic secretory epithelium and genuine lactating adenomas after weaning. These transgenic rat models confirm the conclusions reached in transgenic mice that overexpression of the c-erbB-2 and TGFα genes predisposes the mammary gland to stochastic tumor development. PMID:10393862

  18. Quantitative assessment of mammary gland development in female Long Evans rats following in utero exposure to atrazine.

    Science.gov (United States)

    Hovey, Russell C; Coder, Pragati Sawhney; Wolf, Jeffrey C; Sielken, Robert L; Tisdel, Merrill O; Breckenridge, Charles B

    2011-02-01

    In this study, we quantified the effects of in utero exposure to the herbicide atrazine on subsequent mammary gland development. Atrazine was administered to pregnant female Long Evans rats from gestation days 13-19 at doses of 0, 6.5, 50, or 100 mg/kg/day. A pair-fed control group was yoked to the high-dose atrazine-treated group. Litter size was standardized to 10 pups on postnatal day (PND) 4. Whole mounts of the left fourth mammary gland and histologic sections of the right fourth gland were obtained from a subgroup of offspring on PND1, 21, 33, on day of vaginal opening (VO), or around PND65 at diestrus. A blinded, quantitative analysis of key morphological features in mammary gland whole mounts (ductal elongation, ductal network area, epithelial area, terminal end bud [TEB] incidence, and epithelial density) as well as epithelial proliferation within different parenchymal structures was conducted. There was no effect of atrazine exposure on any of the measures of mammary gland development at the maternal dose of 6.5 mg/kg/day. On PND1, ductal elongation was increased by approximately 20% (p < 0.05) in the female offspring born to dams exposed to 50 and 100 mg/kg/day atrazine, coincident with decreased epithelial proliferation in the 100 mg/kg/day group at this age. These differences were not present on PND21, or thereafter. An increased incidence of TEB in the mammary glands from females that were born to both the pair-fed and 50 mg/kg/day-treated dams at the time of VO indicated that this response was a specific result of maternal caloric restriction. Collectively, these data indicate that maternal atrazine exposure has no long-term effects on mammary gland development in female offspring beyond a transitory response to high doses at PND1.

  19. Development of a RNA extraction method from milk for gene expression study in the mammary gland of sheep.

    Science.gov (United States)

    Mura, Maria Consuelo; Daga, Cinzia; Bodano, Sara; Paludo, Marta; Luridiana, Sebastiano; Pazzola, Michele; Dettori, Maria Luisa; Vacca, Giuseppe Massimo; Carcangiu, Vincenzo

    2013-03-01

    The aim of the study was to develop a reliable method for the RNA extraction from milk of Sarda sheep breed and to highlight if the extracted RNA can be used for expression study on mammary genes involved in milk fat synthesis using RT-qPCR. The main result is that a sample of 150 ml of milk provides an optimal amount of RNA (73.5 μg/ml). The highest RNA concentration has been found in the samples analysed within 4 h after collection. The RNA extracted was positively correlated to the number of somatic cells (P Ct value, for SREBPF1 gene of 26.8 ± 0.15. This research demonstrated that the high-quality of the RNA obtained is suited to use for studies of mammary genes expression in sheep, avoiding any damage caused by mammary gland biopsy.

  20. Poly-ADP ribosylation of PTEN by tankyrases promotes PTEN degradation and tumor growth

    OpenAIRE

    Li, Nan; Zhang, Yajie; Han, Xin; Liang, Ke; Wang, Jiadong; Feng, Lin; Wang, Wenqi; Songyang, Zhou; Lin, Chunru; Yang, Liuqing; Yu, Yonghao; Chen, Junjie

    2015-01-01

    Li et al. report ADP-ribosylation as a new post-translational modification of the tumor suppressor PTEN. Tankyrases interact with and ribosylate PTEN, which promotes the recognition of PTEN by a PAR-binding E3 ubiquitin ligase, RNF146, leading to PTEN ubiquitination and degradation. Tankyrases were up-regulated and negatively correlated with PTEN expression in human colon carcinomas.

  1. Roles of estrogen and progesterone in normal mammary gland development insights from progesterone receptor null mutant mice and in situ localization of receptor.

    Science.gov (United States)

    Shyamala, G

    1997-01-01

    In contrast to most other organs, the development of normal mammary glands occurs mostly in the postnatal state and in a discontinuous fashion. In all species, the glands are composed of various cell types, and it is the epithelium, embedded in the fatty stroma (commonly known as the "fat pad"), that is targeted for proliferation and differentiation. Hormones, in particular the female sex steroids estrogen and progesterone, are absolutely essential for the proliferation of mammary epithelial cell. However, despite intensive efforts by many laboratories spanning nearly 4 decades, at present, the precise role of these steroids and their relative importance in mammary development remains unclear. This article reviews the general features and the effects of estrogen and progesterone on normal mammary gland development, followed by a discussion of our recent studies, which emphasize the primary importance of progesterone and progesterone receptor for the normal mammary epithelial cell proliferation and differentiation. (c) 1997, Elsevier Science Inc. (Trends Endocrinol Metab 1997;8:34-39).

  2. Expression of Autoactivated Stromelysin-1 in Mammary Glands of Transgenic Mice Leads to a Reactive Stroma During Early Development

    Energy Technology Data Exchange (ETDEWEB)

    Thomasset, N.; Lochter, A.; Sympson, C.J.; Lund, L.R.; Williams, D.R.; Behrendtsen, O.; Werb, Z.; Bissell, M.J.

    1998-04-24

    Extracellular matrix and extracellular matrix-degrading matrix metalloproteinases play a key role in interactions between the epithelium and the mesenchyme during mammary gland development and disease. In patients with breast cancer, the mammary mesenchyme undergoes a stromal reaction, the etiology of which is unknown. We previously showed that targeting of an autoactivating mutant of the matrix metalloproteinase stromelysin-1 to mammary epithelia of transgenic mice resulted in reduced mammary function during pregnancy and development of preneoplastic and neoplastic lesions. Here we examine the cascade of alterations before breast tumor formation in the mammary gland stroma once the expression of the stromelysin-1 transgene commences. Beginning in postpubertal virgin animals, low levels of transgene expression in mammary epithelia led to increased expression of endogenous stromelysin-1 in stromal fibroblasts and up-regulation of other matrix metalloproteinases, without basement membrane disruption. These changes were accompanied by the progressive development of a compensatory reactive stroma, characterized by increased collagen content and vascularization in glands from virgin mice. This remodeling of the gland affected epithelial-mesenchymal communication as indicated by inappropriate expression of tenascin-C starting by day 6 of pregnancy. This, together with increased transgene expression, led to basement membrane disruption starting by day 15 of pregnancy. We propose that the highly reactive stroma provides a prelude to breast epithelial tumors observed in these animals. Epithelial development depends on an exquisite series of inductive and instructive interactions between the differentiating epithelium and the mesenchymal (stromal) compartment. The epithelium, which consists of luminal and myoepithelial cells, is separated from the stroma by a basement membrane (BM), which plays a central role in mammary gland homeostasis and gene expression. In vivo, stromal

  3. From milk to malignancy: the role of mammary stem cells in development, pregnancy and breast cancer.

    Science.gov (United States)

    Tiede, Benjamin; Kang, Yibin

    2011-02-01

    Adult stem cells of the mammary gland (MaSCs) are a highly dynamic population of cells that are responsible for the generation of the gland during puberty and its expansion during pregnancy. In recent years significant advances have been made in understanding how these cells are regulated during these developmentally important processes both in humans and in mice. Understanding how MaSCs are regulated is becoming a particularly important area of research, given that they may be particularly susceptible targets for transformation in breast cancer. Here, we summarize the identification of MaSCs, how they are regulated and the evidence for their serving as the origins of breast cancer. In particular, we focus on how changes in MaSC populations may explain both the increased risk of developing aggressive ER/PR(-) breast cancer shortly after pregnancy and the long-term decreased risk of developing ER/PR(+) tumors.

  4. From milk to malignancy: the role of mammary stem cells in development, pregnancy and breast cancer

    Institute of Scientific and Technical Information of China (English)

    Benjamin Tiede; Yibin Kang

    2011-01-01

    Adult stem cells of the mammary gland (MaSCs) are a highly dynamic population of cells that are responsible for the generation of the gland during puberty and its expansion during pregnancy, in recent years significant advances have been made in understanding how these cells are regulated during these developmentally important processes both in humans and in mice. Understanding how MaSCs are regulated is becoming a particularly important area of research, given that they may be particularly susceptible targets for transformation in breast cancer. Here, we summarize the identification of MaSCs, how they are regulated and the evidence for their serving as the origins of breast cancer, in particular, we focus on how changes in MaSC populations may explain both the increased risk of developing aggressive ERJPR(-) breast cancer shortly after pregnancy and the long-term decreased risk of developing ER/ PR(+) tumors.

  5. What controls PTEN and what it controls (in prostate cancer)

    Institute of Scientific and Technical Information of China (English)

    Paramita M Ghosh

    2012-01-01

    The standard of care for metastatic prostate cancer (PCa) is androgen deprivation therapy since almost all PCa growth is initially reliant on the androgen receptor (AR).However,almost all patients develop resistance to this therapy within 18-24months,and current treatment for castration-resistant prostate cancer (CRPC) is extremely limited,despite the advent of new drugs that target the AR,such as ahiraterone and MDV3100.1 Multiple studies have associated the loss of phosphatase and tensin homolog deleted on chromosome 10(PTEN),a dual lipid and protein phosphatase that is frequently lost in prostate cancer,with the development of CRPC.2,3 Yet,multiple studies have shown that at least 20%-40%of primary PCa,which are almost always androgen sensitive,experience a loss of PTEN,4,5 while as many as 30% of CRPC tumors are PTEN-positive.6 The broad questions then facing researchers are:(i) How does PTEN loss cause CRPC?;(ii) What is the mechanism of CRPC development in PTEN+/+ tumors?;and (iii) How can CRPC tumors be inhibited in PTEN-null cells?Three new publications in recent times have come up with mechanisms that answer these questions.7-9 Two of these,both in Cancer Cell eadier this year,from the laboratories of Dr Charles Sawyers and Dr Hong Wu,address a novel negative feedback regulation between AR and PTEN,and all three,including the one from Dr Damu Tang,show that the loss of PTEN function is likely the first step towards the development of CRPC.

  6. A functional connection between pRB and transforming growth factor beta in growth inhibition and mammary gland development.

    Science.gov (United States)

    Francis, Sarah M; Bergsied, Jacqueline; Isaac, Christian E; Coschi, Courtney H; Martens, Alison L; Hojilla, Carlo V; Chakrabarti, Subrata; Dimattia, Gabriel E; Khoka, Rama; Wang, Jean Y J; Dick, Frederick A

    2009-08-01

    Transforming growth factor beta (TGF-beta) is a crucial mediator of breast development, and loss of TGF-beta-induced growth arrest is a hallmark of breast cancer. TGF-beta has been shown to inhibit cyclin-dependent kinase (CDK) activity, which leads to the accumulation of hypophosphorylated pRB. However, unlike other components of TGF-beta cytostatic signaling, pRB is thought to be dispensable for mammary development. Using gene-targeted mice carrying subtle missense changes in pRB (Rb1(DeltaL) and Rb1(NF)), we have discovered that pRB plays a critical role in mammary gland development. In particular, Rb1 mutant female mice have hyperplastic mammary epithelium and defects in nursing due to insensitivity to TGF-beta growth inhibition. In contrast with previous studies that highlighted the inhibition of cyclin/CDK activity by TGF-beta signaling, our experiments revealed that active transcriptional repression of E2F target genes by pRB downstream of CDKs is also a key component of TGF-beta cytostatic signaling. Taken together, our work demonstrates a unique functional connection between pRB and TGF-beta in growth control and mammary gland development.

  7. In-silico QTL mapping of postpubertal mammary ductal development in the mouse uncovers potential human breast cancer risk loci

    Science.gov (United States)

    Genetic background plays a dominant role in mammary gland development and breast cancer (BrCa). Despite this, the role of genetics is only partially understood. This study used strain-dependent variation in an inbred mouse mapping panel, to identify quantitative trait loci (QTL) underlying structura...

  8. Mammary gland development and response to prenatal atrazine exposure in the Sprague Dawley and Long-Evans rats.

    Science.gov (United States)

    Mammary gland (MG) tumor development in Sprague Dawley (SD) rats is increased by longterm dietary exposure to the chlorotriazine herbicide atrazine (ATR). ATR is proposed to cause these changes in the adult SD rat by altering hormonally-regulated estrous cyclicity. In Long-Evans...

  9. Elf5 inhibits the epithelial-mesenchymal transition in mammary gland development and breast cancer metastasis by transcriptionally repressing Snail2.

    Science.gov (United States)

    Chakrabarti, Rumela; Hwang, Julie; Andres Blanco, Mario; Wei, Yong; Lukačišin, Martin; Romano, Rose-Anne; Smalley, Kirsten; Liu, Song; Yang, Qifeng; Ibrahim, Toni; Mercatali, Laura; Amadori, Dino; Haffty, Bruce G; Sinha, Satrajit; Kang, Yibin

    2012-11-01

    The epithelial-mesenchymal transition (EMT) is a complex process that occurs during organogenesis and in cancer metastasis. Despite recent progress, the molecular pathways connecting the physiological and pathological functions of EMT need to be better defined. Here we show that the transcription factor Elf5, a key regulator of mammary gland alveologenesis, controls EMT in both mammary gland development and metastasis. We uncovered this role for Elf5 through analyses of Elf5 conditional knockout animals, various in vitro and in vivo models of EMT and metastasis, an MMTV-neu transgenic model of mammary tumour progression and clinical breast cancer samples. Furthermore, we demonstrate that Elf5 suppresses EMT by directly repressing the transcription of Snail2, a master regulator of mammary stem cells and a known inducer of EMT. These findings establish Elf5 not only as a key cell lineage regulator during normal mammary gland development, but also as a suppressor of EMT and metastasis in breast cancer.

  10. Oncogenic AKT1(E17K) mutation induces mammary hyperplasia but prevents HER2-driven tumorigenesis.

    Science.gov (United States)

    Mancini, Maria L; Lien, Evan C; Toker, Alex

    2016-04-05

    One of the most frequently deregulated signaling pathways in breast cancer is the PI 3-K/Akt cascade. Genetic lesions are commonly found in PIK3CA, PTEN, and AKT, which lead to excessive and constitutive activation of Akt and downstream signaling that results in uncontrolled proliferation and increased cellular survival. One such genetic lesion is the somatic AKT1(E17K) mutation, which has been identified in 4-8% of breast cancer patients. To determine how this mutation contributes to mammary tumorigenesis, we constructed a genetically engineered mouse model that conditionally expresses human AKT1(E17K) in the mammary epithelium. Although AKT1(E17K) is only weakly constitutively active and does not promote proliferation in vitro, it is capable of escaping negative feedback inhibition to exhibit sustained signaling dynamics in vitro. Consistently, both virgin and multiparous AKT1(E17K) mice develop mammary gland hyperplasia that do not progress to carcinoma. This hyperplasia is accompanied by increased estrogen receptor expression, although exposure of the mice to estrogen does not promote tumor development. Moreover, AKT1(E17K) prevents HER2-driven mammary tumor formation, in part through negative feedback inhibition of RTK signaling. Analysis of TCGA breast cancer data revealed that the mRNA expression, total protein levels, and phosphorylation of various RTKs are decreased in human tumors harboring AKT1(E17K).

  11. Mammary Duct Ectasia

    Science.gov (United States)

    ... tenderness or inflammation of the clogged duct (periductal mastitis). Mammary duct ectasia most often occurs in women ... that's turned inward (inverted) A bacterial infection called mastitis also may develop in the affected milk duct, ...

  12. Design And Development Of A Mammary And Axillary Region Positron Emission Tomography System (maxpet)

    CERN Document Server

    Doshi, N K

    2000-01-01

    Breast cancer is the second leading cause of cancer death in women. Currently, mammography and physical breast examination, both non-invasive techniques, provide the two most effective methods available for screening potential breast cancer patients. During the management of patients, however, several invasive techniques such as axillary lymph node dissection, core biopsies and lumpectomies, are utilized to determine the stage or malignancy of the disease with significant cost and morbidity associated with them. Positron Emission Tomography (PET), using [F-18] fluorodeoxyglucose (FDG) tracer is a sensitive and non-invasive imaging modality that may be a cost-effective alternative to certain invasive procedures. In this project we have developed a low cost, high performance, dedicated PET camera (maxPET) for mammary and axillary region imaging. The system consists of two 15x15 cm2 planar scintillation detector arrays composed of modular detectors operating in coincidence. The modular detectors are comprised of...

  13. SNORD-host RNA Zfas1 is a regulator of mammary development and a potential marker for breast cancer.

    Science.gov (United States)

    Askarian-Amiri, Marjan E; Crawford, Joanna; French, Juliet D; Smart, Chanel E; Smith, Martin A; Clark, Michael B; Ru, Kelin; Mercer, Tim R; Thompson, Ella R; Lakhani, Sunil R; Vargas, Ana C; Campbell, Ian G; Brown, Melissa A; Dinger, Marcel E; Mattick, John S

    2011-05-01

    Long noncoding RNAs (lncRNAs) are increasingly recognized to play major regulatory roles in development and disease. To identify novel regulators in breast biology, we identified differentially regulated lncRNAs during mouse mammary development. Among the highest and most differentially expressed was a transcript (Zfas1) antisense to the 5' end of the protein-coding gene Znfx1. In vivo, Zfas1 RNA is localized within the ducts and alveoli of the mammary gland. Zfas1 intronically hosts three previously undescribed C/D box snoRNAs (SNORDs): Snord12, Snord12b, and Snord12c. In contrast to the general assumption that noncoding SNORD-host transcripts function only as vehicles to generate snoRNAs, knockdown of Zfas1 in a mammary epithelial cell line resulted in increased cellular proliferation and differentiation, while not substantially altering the levels of the SNORDs. In support of an independent function, we also found that Zfas1 is extremely stable, with a half-life >16 h. Expression analysis of the SNORDs revealed these were expressed at different levels, likely a result of distinct structures conferring differential stability. While there is relatively low primary sequence conservation between Zfas1 and its syntenic human ortholog ZFAS1, their predicted secondary structures have similar features. Like Zfas1, ZFAS1 is highly expressed in the mammary gland and is down-regulated in breast tumors compared to normal tissue. We propose a functional role for Zfas1/ ZFAS1 in the regulation of alveolar development and epithelial cell differentiation in the mammary gland, which, together with its dysregulation in human breast cancer, suggests ZFAS1 as a putative tumor suppressor gene.

  14. Hydrocephalus caused by conditional ablation of the Pten or beta-catenin gene

    Directory of Open Access Journals (Sweden)

    Ohtoshi Akihira

    2008-10-01

    Full Text Available Abstract To investigate the roles of Pten and β-Catenin in the midbrain, either the Pten gene or the β-catenin gene was conditionally ablated, using Dmbx1 (diencephalon/mesencephalon-expressed brain homeobox gene 1-Cre mice. Homozygous disruption of the Pten or β-catenin gene in Dmbx1-expressing cells caused severe hydrocephalus and mortality during the postnatal period. Conditional deletion of Pten resulted in enlargement of midbrain structures. β-catenin conditional mutant mice showed malformation of the superior and inferior colliculi and stenosis of the midbrain aqueduct. These results demonstrate that both Pten and β-Catenin are essential for proper midbrain development, and provide the direct evidence that mutations of both Pten and β-catenin lead to hydrocephalus.

  15. Mammary epithelial cell

    DEFF Research Database (Denmark)

    Kass, Laura; Erler, Janine Terra; Dembo, Micah

    2007-01-01

    a repertoire of transmembrane receptors, of which integrins are the best characterized. Integrins modulate cell fate by reciprocally transducing biochemical and biophysical cues between the cell and the extracellular matrix, facilitating processes such as embryonic branching morphogenesis and lactation...... in the mammary gland. During breast development and cancer progression, the extracellular matrix is dynamically altered such that its composition, turnover, processing and orientation change dramatically. These modifications influence mammary epithelial cell shape, and modulate growth factor and hormonal...

  16. Characterization of novel non-clonal intrachromosomal rearrangements between the H4 and PTEN genes (H4/PTEN) in human thyroid cell lines and papillary thyroid cancer specimens

    Energy Technology Data Exchange (ETDEWEB)

    Puxeddu, Efisio [Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, PO Box 670547, Cincinnati, OH 45267-0547 (United States); Zhao Guisheng [Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, PO Box 670547, Cincinnati, OH 45267-0547 (United States); Stringer, James R. [Department of Molecular Genetics, University of Cincinnati College of Medicine, PO Box 670547, Cincinnati, OH 45267-0547 (United States); Medvedovic, Mario [Center for Biostatistic Service, University of Cincinnati College of Medicine, PO Box 670547, Cincinnati, OH 45267-0547 (United States); Moretti, Sonia [Dipartimento di Medicina Interna, Universita degli Studi di Perugia, Via E. dal Pozzo, Perugia 06126, (Italy); Fagin, James A. [Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, PO Box 670547, Cincinnati, OH 45267-0547 (United States)]. E-mail: james.fagin@uc.edu

    2005-02-15

    The two main forms of RET rearrangement in papillary thyroid carcinomas (PTC) arise from intrachromosomal inversions fusing the tyrosine kinase domain of RET with either the H4 (RET/PTC1) or the ELE1/RFG genes (RET/PTC3). PTEN codes for a dual-specificity phosphatase and maps to chromosome 10q22-23. Germline mutations confer susceptibility to Cowden syndrome whereas somatic mutations or deletions are common in several sporadic human tumors. Decreased PTEN expression has been implicated in thyroid cancer development. We report the characterization of a new chromosome 10 rearrangement involving H4 and PTEN. The initial H4/PTEN rearrangement was discovered as a non-specific product of RT-PCR for RET/PTC1 in irradiated thyroid cell lines. Sequencing revealed a transcript consisting of exon 1 and 2 of H4 fused with exons 3-6 of PTEN. Nested RT-PCR with specific primers bracketing the breakpoints confirmed the H4/PTEN rearrangements in irradiated KAT-1 and KAT-50 cells. Additional H4/PTEN variants, generated by recombination of either exon 1 or exon 2 of H4 with exon 6 of PTEN, were found in non-irradiated KAK-1, KAT-50, ARO and NPA cells. Their origin through chromosomal recombination was confirmed by detection of the reciprocal PTEN/H4 product. H4/PTEN recombination was not a clonal event in any of the cell lines, as Southern blots with appropriate probes failed to demonstrate aberrant bands, and multicolor FISH of KAK1 cells with BAC probes for H4 and PTEN did not show a signal overlap in all cells. Based on PCR of serially diluted samples, the minimal frequency of spontaneous recombination between these loci was estimated to be approximately 1/10{sup 6} cells. H4/PTEN products were found by nested RT-PCR in 4/14 normal thyroid tissues (28%) and 14/18 PTC (78%) (P < 0.01). H4/PTEN is another example of recombination involving the H4 locus, and points to the high susceptibility of thyroid cells to intrachromosomal gene rearrangements. As this also represents a

  17. The Role of BRCA1 in Suppressing Epithelial Mesenchymal Transition in Mammary Gland and Tumor Development

    Science.gov (United States)

    2016-11-01

    J signaling pathway controls the balance of cell lineages in mammary epithelium during pregnancy . Dev Biol. 2006;293(2):565-80. Epub 2006/04/04. doi...lineages in mammary epithelium during pregnancy . Dev Biol 2006;293:565–80. 32. Lim E, Wu D, Pal B, Bouras T, Asselin-Labat ML, Vaillant F, et al...linked with multiple pathways including DNA damage repair and oxidative stress regulation [19]. Functional loss of BRCA1 by germline or somatic

  18. A role for Pten in paediatric intestinal dysmotility disorders.

    LENUS (Irish Health Repository)

    O'Donnell, Anne-Marie

    2012-02-01

    PURPOSE: The enteric nervous system (ENS) is a network of neurons and glia that lies within the gut wall. It is responsible for the normal regulation of gut motility and secretory activities. Hirschsprung\\'s disease (HD) is a congenital defect of the ENS, characterised by an absence of ganglia in the distal colon. Intestinal neuronal dysplasia (IND) is a condition that clinically resembles HD, characterised by hyperganglionosis, giant and ectopic ganglia, resulting in intestinal dysmotility. Intestinal ganglioneuromatosis is characterised by hyperplasia and hypertrophy of enteric neuronal cells and causes chronic intestinal pseudo-obstruction (CIPO). Phosphatase and tensin homolog deleted on chromosome 10 (Pten) is a phosphatase that is critical for controlling cell growth, proliferation and cell death. A recent study of Pten knockout mice showed evidence of ganglioneuromatosis in the ENS suggesting a role for this protein in ENS development. Ganglioneuromatosis patients have also been shown to have a decreased level of Pten expression in the colon. The aim of our study was to investigate Pten expression in the ENS of HD and IND patients compared to normal controls. METHODS: Resected tissue from 10 HD and 10 IND type B patients was fixed and embedded in paraffin wax. Normal control colon tissue was obtained from ten patients who underwent a colostomy closure for imperforate anus. Sections were cut and immunohistochemistry was carried out using a Pten antibody. Results were analysed by light microscopy. RESULTS: Staining showed that Pten was strongly expressed in ganglia of both the submucosal and myenteric plexus of normal and HD specimens from the ganglionic colon. Pten expression was significantly reduced in the giant ganglia in IND patients in both the myenteric and submucosal plexuses compared to the normal controls. Specimens from the aganglionic region of HD did not show Pten expression. CONCLUSION: To the best of our knowledge, this is the first study

  19. Redefining the expression and function of the inhibitor of differentiation 1 in mammary gland development.

    Directory of Open Access Journals (Sweden)

    Radhika Nair

    Full Text Available The accumulation of poorly differentiated cells is a hallmark of breast neoplasia and progression. Thus an understanding of the factors controlling mammary differentiation is critical to a proper understanding of breast tumourigenesis. The Inhibitor of Differentiation 1 (Id1 protein has well documented roles in the control of mammary epithelial differentiation and proliferation in vitro and breast cancer progression in vivo. However, it has not been determined whether Id1 expression is sufficient for the inhibition of mammary epithelial differentiation or the promotion of neoplastic transformation in vivo. We now show that Id1 is not commonly expressed by the luminal mammary epithelia, as previously reported. Generation and analysis of a transgenic mouse model of Id1 overexpression in the mammary gland reveals that Id1 is insufficient for neoplastic progression in virgin animals or to prevent terminal differentiation of the luminal epithelia during pregnancy and lactation. Together, these data demonstrate that there is no luminal cell-autonomous role for Id1 in mammary epithelial cell fate determination, ductal morphogenesis and terminal differentiation.

  20. Selective neuronal PTEN deletion: can we take the brakes off of growth without losing control?

    Science.gov (United States)

    Gutilla, Erin A; Steward, Oswald

    2016-08-01

    The limited ability for injured adult axons to regenerate is a major cause for limited functional recovery after injury to the nervous system, motivating numerous efforts to uncover mechanisms capable of enhancing regeneration potential. One promising strategy involves deletion or knockdown of the phosphatase and tensin (PTEN) gene. Conditional genetic deletion of PTEN before, immediately following, or several months after spinal cord injury enables neurons of the corticospinal tract (CST) to regenerate their axons across the lesion, which is accompanied by enhanced recovery of skilled voluntary motor functions mediated by the CST. Although conditional genetic deletion or knockdown of PTEN in neurons enables axon regeneration, PTEN is a well-known tumor suppressor and mutations of the PTEN gene disrupt brain development leading to neurological abnormalities including macrocephaly, seizures, and early mortality. The long-term consequences of manipulating PTEN in the adult nervous system, as would be done for therapeutic intervention after injury, are only now being explored. Here, we summarize evidence indicating that long-term deletion of PTEN in mature neurons does not cause evident pathology; indeed, cortical neurons that have lived without PTEN for over 1 year appear robust and healthy. Studies to date provide only a first look at potential negative consequences of PTEN deletion or knockdown, but the absence of any detectable neuropathology supports guarded optimism that interventions to enable axon regeneration after injury are achievable.

  1. Selective neuronal PTEN deletion: can we take the brakes off of growth without losing control?

    Directory of Open Access Journals (Sweden)

    Erin A Gutilla

    2016-01-01

    Full Text Available The limited ability for injured adult axons to regenerate is a major cause for limited functional recovery after injury to the nervous system, motivating numerous efforts to uncover mechanisms capable of enhancing regeneration potential. One promising strategy involves deletion or knockdown of the phosphatase and tensin (PTEN gene. Conditional genetic deletion of PTEN before, immediately following, or several months after spinal cord injury enables neurons of the corticospinal tract (CST to regenerate their axons across the lesion, which is accompanied by enhanced recovery of skilled voluntary motor functions mediated by the CST. Although conditional genetic deletion or knockdown ofPTEN in neurons enables axon regeneration, PTEN is a well-known tumor suppressor and mutations of the PTEN gene disrupt brain development leading to neurological abnormalities including macrocephaly, seizures, and early mortality. The long-term consequences of manipulating PTEN in the adult nervous system, as would be done for therapeutic intervention after injury, are only now being explored. Here, we summarize evidence indicating that long-term deletion of PTEN in mature neurons does not cause evident pathology; indeed, cortical neurons that have lived without PTEN for over 1 year appear robust and healthy. Studies to date provide only a first look at potential negative consequences of PTEN deletion or knockdown, but the absence of any detectable neuropathology supports guarded optimism that interventions to enable axon regeneration after injury are achievable.

  2. Evolution of somatic mutations in mammary tumors in transgenic mice is influenced by the inherited genotype

    Directory of Open Access Journals (Sweden)

    Li Yi

    2004-06-01

    Full Text Available Abstract Background MMTV-Wnt1 transgenic mice develop mammary hyperplasia early in development, followed by the appearance of solitary mammary tumors with a high proportion of cells expressing early lineage markers and many myoepithelial cells. The occurrence of tumors is accelerated in experiments that activate FGF proto-oncogenes or remove the tumor suppressor genes Pten or P53, implying that secondary oncogenic events are required for progression from mammary hyperplasia to carcinoma. It is not known, however, which oncogenic pathways contribute to Wnt1-induced tumorigenesis – further experimental manipulation of these mice is needed. Secondary events also appear to be required for mammary tumorigenesis in MMTV-Neu transgenic mice because the transgene in the tumors usually contains an acquired mutation that activates the Neu protein-tyrosine kinase. Methods cDNA or DNA from the mammary glands and mammary tumors from MMTV-Wnt1, MMTV-Wnt1/p53-/-, MMTV-Neu transgenic mice, and newly generated MMTV-Wnt1/MMTV-Neu bitransgenic mice, was sequenced to seek activating mutations in H-Ras, K-Ras, and N-Ras genes, or in the MMTV-Neu transgene. In addition, tumors from bitransgenic animals were examined to determine the cellular phenotype. Results We found activating mutations at codons 12, 13, and 61 of H-Ras in just over half of the mammary tumors in MMTV-Wnt1 transgenic mice, and we confirmed the high frequency of activating mutations of Neu in tumors in MMTV-Neu transgenic mice. Tumors appeared earlier in bitransgenic MMTV-Wnt1/MMTV-Neu mice, but no Ras or MMTV-Neu mutations were found in these tumors, which were phenotypically similar to those arising in MMTV-Wnt1 mice. In addition, no Ras mutations were found in the mammary tumors that arise in MMTV-Wnt1 transgenic mice lacking an intact P53 gene. Conclusions Tumorigenic properties of cells undergoing functionally significant secondary mutations in H-Ras or the MMTV-Neu transgene allow selection

  3. Genetic suppression reveals DNA repair-independent antagonism between BRCA1 and COBRA1 in mammary gland development.

    Science.gov (United States)

    Nair, Sreejith J; Zhang, Xiaowen; Chiang, Huai-Chin; Jahid, Md Jamiul; Wang, Yao; Garza, Paula; April, Craig; Salathia, Neeraj; Banerjee, Tapahsama; Alenazi, Fahad S; Ruan, Jianhua; Fan, Jian-Bing; Parvin, Jeffrey D; Jin, Victor X; Hu, Yanfen; Li, Rong

    2016-03-04

    The breast cancer susceptibility gene BRCA1 is well known for its function in double-strand break (DSB) DNA repair. While BRCA1 is also implicated in transcriptional regulation, the physiological significance remains unclear. COBRA1 (also known as NELF-B) is a BRCA1-binding protein that regulates RNA polymerase II (RNAPII) pausing and transcription elongation. Here we interrogate functional interaction between BRCA1 and COBRA1 during mouse mammary gland development. Tissue-specific deletion of Cobra1 reduces mammary epithelial compartments and blocks ductal morphogenesis, alveologenesis and lactogenesis, demonstrating a pivotal role of COBRA1 in adult tissue development. Remarkably, these developmental deficiencies due to Cobra1 knockout are largely rescued by additional loss of full-length Brca1. Furthermore, Brca1/Cobra1 double knockout restores developmental transcription at puberty, alters luminal epithelial homoeostasis, yet remains deficient in homologous recombination-based DSB repair. Thus our genetic suppression analysis uncovers a previously unappreciated, DNA repair-independent function of BRCA1 in antagonizing COBRA1-dependent transcription programme during mammary gland development.

  4. Hyperactivity of Newborn Pten Knock-out Neurons Results from Increased Excitatory Synaptic Drive

    Science.gov (United States)

    Williams, Michael R.; DeSpenza, Tyrone; Li, Meijie; Gulledge, Allan T.

    2015-01-01

    Developing neurons must regulate morphology, intrinsic excitability, and synaptogenesis to form neural circuits. When these processes go awry, disorders, including autism spectrum disorder (ASD) or epilepsy, may result. The phosphatase Pten is mutated in some patients having ASD and seizures, suggesting that its mutation disrupts neurological function in part through increasing neuronal activity. Supporting this idea, neuronal knock-out of Pten in mice can cause macrocephaly, behavioral changes similar to ASD, and seizures. However, the mechanisms through which excitability is enhanced following Pten depletion are unclear. Previous studies have separately shown that Pten-depleted neurons can drive seizures, receive elevated excitatory synaptic input, and have abnormal dendrites. We therefore tested the hypothesis that developing Pten-depleted neurons are hyperactive due to increased excitatory synaptogenesis using electrophysiology, calcium imaging, morphological analyses, and modeling. This was accomplished by coinjecting retroviruses to either “birthdate” or birthdate and knock-out Pten in granule neurons of the murine neonatal dentate gyrus. We found that Pten knock-out neurons, despite a rapid onset of hypertrophy, were more active in vivo. Pten knock-out neurons fired at more hyperpolarized membrane potentials, displayed greater peak spike rates, and were more sensitive to depolarizing synaptic input. The increased sensitivity of Pten knock-out neurons was due, in part, to a higher density of synapses located more proximal to the soma. We determined that increased synaptic drive was sufficient to drive hypertrophic Pten knock-out neurons beyond their altered action potential threshold. Thus, our work contributes a developmental mechanism for the increased activity of Pten-depleted neurons. PMID:25609613

  5. Effects of soy-derived isoflavones and a high-fat diet on spontaneous mammary rimor development in Tg.NK (MMTV/c-neu) mice

    DEFF Research Database (Denmark)

    Luijten, M.; Thomsen, A.R.; van den Berg, J.A.H.;

    2004-01-01

    Phytoestrogens such as isoflavonoids and lignans have been postulated as breast cancer protective constituents in soy and whole-grain cereals. We investigated the ability of isoflavones (IFs) and flaxseed to modulate spontaneous mammary tumor development in female heterozygous Tg.NK (MMTV...... to IFs and flaxseed tended to accelerate the onset of mammary adenocarcinoma development, although tumor burden at necropsy was not changed significantly. Perinatal IF exposure resulted in enhanced mammary gland differentiation, but palpable mammary tumor onset was not affected. However, tumor burden...... at necropsy in the perinatal exposure study was significantly increased in the medium- and high-IF dose groups. Comparison of both exposure scenarios revealed a strongly accelerated onset of tumor growth after perinatal high-fat diet exposure compared with the low-fat diet. This study shows that breast cancer...

  6. Cancer risk and genotype-phenotype correlations in PTEN hamartoma tumor syndrome

    NARCIS (Netherlands)

    Nieuwenhuis, M.H.; Kets, C.M.; Murphy-Ryan, M.; Yntema, H.G.; Evans, D.G.; Colas, C.; Moller, P.; Hes, F.J.; Hodgson, S.V.; Olderode-Berends, M.J.; Aretz, S.; Heinimann, K.; Garcia, E.B.; Douglas, F.; Spigelman, A.; Timshel, S.; Lindor, N.M.; Vasen, H.F.

    2014-01-01

    Patients with germline PTEN mutations are at high risk of developing benign and malignant tumours. We aimed to evaluate the cumulative risk of several types of cancer and of dysplastic cerebellar gangliocytoma (Lhermitte-Duclos disease, LDD). In addition, genotype-phenotype correlations in PTEN hama

  7. Identification of reliable reference genes for qRT-PCR studies of the developing mouse mammary gland

    Science.gov (United States)

    van de Moosdijk, Anoeska Agatha Alida; van Amerongen, Renée

    2016-01-01

    Cell growth and differentiation are often driven by subtle changes in gene expression. Many challenges still exist in detecting these changes, particularly in the context of a complex, developing tissue. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) allows relatively high-throughput evaluation of multiple genes and developmental time points. Proper quantification of gene expression levels by qRT-PCR requires normalization to one or more reference genes. Traditionally, these genes have been selected based on their presumed “housekeeping” function, with the implicit assumption that they are stably expressed over the entire experimental set. However, this is rarely tested empirically. Here we describe the identification of novel reference genes for the mouse mammary gland based on their stable expression in published microarray datasets. We compared eight novel candidate reference genes (Arpc3, Clock, Ctbp1, Phf7, Prdx1, Sugp2, Taf11 and Usp7) to eight traditional ones (18S, Actb, Gapdh, Hmbs, Hprt, Rpl13a, Sdha and Tbp) and analysed all genes for stable expression in the mouse mammary gland from pre-puberty to adulthood using four different algorithms (GeNorm, DeltaCt, BestKeeper and NormFinder). Prdx1, Phf7 and Ctbp1 were validated as novel and reliable, tissue-specific reference genes that outperform traditional reference genes in qRT-PCR studies of postnatal mammary gland development. PMID:27752147

  8. t10,c12-CLA decreases adiposity in peripubertal mice without dose-related detrimental effects on mammary development, inflammation status, and metabolism.

    Science.gov (United States)

    Foote, M R; Giesy, S L; Bernal-Santos, G; Bauman, D E; Boisclair, Y R

    2010-12-01

    The trans 10, cis 12-conjugated linoleic acid (10,12-CLA) isomer reduces adiposity in several animal models. In the mouse, however, this effect is associated with adipose tissue inflammation, hyperinsulinemia and hepatic lipid accumulation. Moreover, 10,12-CLA was recently shown to promote mammary ductal hyperplasia and ErbB2/Her2-driven mammary cancer in the mouse. Reasons for detrimental effects of 10,12-CLA on the mouse mammary gland could relate to its effect on the mammary fat pad (MFP), which is essential for normal development. Accordingly, we hypothesized that mammary effects of 10,12-CLA were mediated through the MFP in a dose-dependent manner. Female FVB mice were fed 10,12-CLA at doses of 0%, 0.1%, 0.2%, or 0.5% of the diet from day 24 of age, and effects on mammary development and metabolism were measured on day 49. The 0.5% dose reduced ductal elongation and caused premature alveolar budding. These effects were associated with increased expression of inflammatory markers and genes shown to alter epithelial growth (IGF binding protein-5) and alveolar budding (TNF-α and receptor of activated NF-κB ligand). The 0.5% dose also caused hyperinsulinemia and hepatic lipid accumulation. In contrast, the 0.1% 10,12-CLA dose had no adverse effects on mammary development, metabolic events, and inflammatory responses, but remained effective in decreasing adipose weights and lipogenic gene expression. These results show that a low dose of 10,12-CLA reduces adiposity in the mouse without negative effects on mammary development, inflammation, and metabolism, and suggest that previously reported detrimental effects relate to the use of excessive doses.

  9. Cell-Type Specific Roles for PTEN in Establishing a Functional Retinal Architecture

    Science.gov (United States)

    Cantrup, Robert; Dixit, Rajiv; Palmesino, Elena; Bonfield, Stephan; Shaker, Tarek; Tachibana, Nobuhiko; Zinyk, Dawn; Dalesman, Sarah; Yamakawa, Kazuhiro; Stell, William K.; Wong, Rachel O.; Reese, Benjamin E.; Kania, Artur; Sauvé, Yves; Schuurmans, Carol

    2012-01-01

    Background The retina has a unique three-dimensional architecture, the precise organization of which allows for complete sampling of the visual field. Along the radial or apicobasal axis, retinal neurons and their dendritic and axonal arbors are segregated into layers, while perpendicular to this axis, in the tangential plane, four of the six neuronal types form patterned cellular arrays, or mosaics. Currently, the molecular cues that control retinal cell positioning are not well-understood, especially those that operate in the tangential plane. Here we investigated the role of the PTEN phosphatase in establishing a functional retinal architecture. Methodology/Principal Findings In the developing retina, PTEN was localized preferentially to ganglion, amacrine and horizontal cells, whose somata are distributed in mosaic patterns in the tangential plane. Generation of a retina-specific Pten knock-out resulted in retinal ganglion, amacrine and horizontal cell hypertrophy, and expansion of the inner plexiform layer. The spacing of Pten mutant mosaic populations was also aberrant, as were the arborization and fasciculation patterns of their processes, displaying cell type-specific defects in the radial and tangential dimensions. Irregular oscillatory potentials were also observed in Pten mutant electroretinograms, indicative of asynchronous amacrine cell firing. Furthermore, while Pten mutant RGC axons targeted appropriate brain regions, optokinetic spatial acuity was reduced in Pten mutant animals. Finally, while some features of the Pten mutant retina appeared similar to those reported in Dscam-mutant mice, PTEN expression and activity were normal in the absence of Dscam. Conclusions/Significance We conclude that Pten regulates somal positioning and neurite arborization patterns of a subset of retinal cells that form mosaics, likely functioning independently of Dscam, at least during the embryonic period. Our findings thus reveal an unexpected level of cellular

  10. Cell-type specific roles for PTEN in establishing a functional retinal architecture.

    Directory of Open Access Journals (Sweden)

    Robert Cantrup

    Full Text Available BACKGROUND: The retina has a unique three-dimensional architecture, the precise organization of which allows for complete sampling of the visual field. Along the radial or apicobasal axis, retinal neurons and their dendritic and axonal arbors are segregated into layers, while perpendicular to this axis, in the tangential plane, four of the six neuronal types form patterned cellular arrays, or mosaics. Currently, the molecular cues that control retinal cell positioning are not well-understood, especially those that operate in the tangential plane. Here we investigated the role of the PTEN phosphatase in establishing a functional retinal architecture. METHODOLOGY/PRINCIPAL FINDINGS: In the developing retina, PTEN was localized preferentially to ganglion, amacrine and horizontal cells, whose somata are distributed in mosaic patterns in the tangential plane. Generation of a retina-specific Pten knock-out resulted in retinal ganglion, amacrine and horizontal cell hypertrophy, and expansion of the inner plexiform layer. The spacing of Pten mutant mosaic populations was also aberrant, as were the arborization and fasciculation patterns of their processes, displaying cell type-specific defects in the radial and tangential dimensions. Irregular oscillatory potentials were also observed in Pten mutant electroretinograms, indicative of asynchronous amacrine cell firing. Furthermore, while Pten mutant RGC axons targeted appropriate brain regions, optokinetic spatial acuity was reduced in Pten mutant animals. Finally, while some features of the Pten mutant retina appeared similar to those reported in Dscam-mutant mice, PTEN expression and activity were normal in the absence of Dscam. CONCLUSIONS/SIGNIFICANCE: We conclude that Pten regulates somal positioning and neurite arborization patterns of a subset of retinal cells that form mosaics, likely functioning independently of Dscam, at least during the embryonic period. Our findings thus reveal an unexpected

  11. Rescue of glandular dysmorphogenesis in PTEN-deficient colorectal cancer epithelium by PPARγ-targeted therapy.

    Science.gov (United States)

    Jagan, I; Fatehullah, A; Deevi, R K; Bingham, V; Campbell, F C

    2013-03-07

    Disruption of glandular architecture associates with poor clinical outcome in high-grade colorectal cancer (CRC). Phosphatase and tensin homolog deleted on chromosome ten (PTEN) regulates morphogenic growth of benign MDCK (Madin Darby Canine Kidney) cells through effects on the Rho-like GTPase cdc42 (cell division cycle 42). This study investigates PTEN-dependent morphogenesis in a CRC model. Stable short hairpin RNA knockdown of PTEN in Caco-2 cells influenced expression or localization of cdc42 guanine nucleotide exchange factors and inhibited cdc42 activation. Parental Caco-2 cells formed regular hollow gland-like structures (glands) with a single central lumen, in three-dimensional (3D) cultures. Conversely, PTEN-deficient Caco-2 ShPTEN cells formed irregular glands with multiple abnormal lumens as well as intra- and/or intercellular vacuoles evocative of the high-grade CRC phenotype. Effects of targeted treatment were investigated. Phosphatidinylinositol 3-kinase (PI3K) modulating treatment did not affect gland morphogenesis but did influence gland number, gland size and/or cell size within glands. As PTEN may be regulated by the nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ), cultures were treated with the PPARγ ligand rosiglitazone. This treatment enhanced PTEN expression, cdc42 activation and rescued dysmorphogenesis by restoring single lumen formation in Caco-2 ShPTEN glands. Rosiglitazone effects on cdc42 activation and Caco-2 ShPTEN gland development were attenuated by cotreatment with GW9662, a PPARγ antagonist. Taken together, these studies show PTEN-cdc42 regulation of lumen formation in a 3D model of human CRC glandular morphogenesis. Treatment by the PPARγ ligand rosiglitazone, but not PI3K modulators, rescued colorectal glandular dysmorphogenesis of PTEN deficiency.

  12. Mammary-specific inactivation of E-cadherin and p53 impairs functional gland development and leads to pleomorphic invasive lobular carcinoma in mice

    Directory of Open Access Journals (Sweden)

    Patrick W. B. Derksen

    2011-05-01

    Breast cancer is the most common malignancy in women of the Western world. Even though a large percentage of breast cancer patients show pathological complete remission after standard treatment regimes, approximately 30–40% are non-responsive and ultimately develop metastatic disease. To generate a good preclinical model of invasive breast cancer, we have taken a tissue-specific approach to somatically inactivate p53 and E-cadherin, the cardinal cell-cell adhesion receptor that is strongly associated with tumor invasiveness. In breast cancer, E-cadherin is found mutated or otherwise functionally silenced in invasive lobular carcinoma (ILC, which accounts for 10–15% of all breast cancers. We show that mammary-specific stochastic inactivation of conditional E-cadherin and p53 results in impaired mammary gland function during pregnancy through the induction of anoikis resistance of mammary epithelium, resulting in loss of epithelial organization and a dysfunctional mammary gland. Moreover, combined inactivation of E-cadherin and p53 induced lactation-independent development of invasive and metastatic mammary carcinomas, which showed strong resemblance to human pleomorphic ILC. Dissemination patterns of mouse ILC mimic the human malignancy, showing metastasis to the gastrointestinal tract, peritoneum, lung, lymph nodes and bone. Our results confirm that loss of E-cadherin contributes to both mammary tumor initiation and metastasis, and establish a preclinical mouse model of human ILC that can be used for the development of novel intervention strategies to treat invasive breast cancer.

  13. PTEN inhibition and axon regeneration and neural repair

    Institute of Scientific and Technical Information of China (English)

    Yosuke Ohtake; Umar Hayat; Shuxin Li

    2015-01-01

    The intrinsic growth ability of all the neurons declines during development although some may grow better than others. Numerous intracellular signaling proteins and transcription factors have been shown to regulate the intrinsic growth capacity in mature neurons. Among them, PI3 kinase/Akt pathway is important for controlling axon elongation. As a negative regulator of this pathway, the tumor suppressor phosphatase and tensin homolog (PTEN) appears critical to con-trol the regenerative ability of young and adult neurons. This review will focus on recent research progress in axon regeneration and neural repair by PTEN inhibition and therapeutic potential of blocking this phosphatase for neurological disorders. Inhibition of PTEN by deletion in con-ditional knockout mice, knockdown by short-hairpin RNA, or blockade by pharmacological approaches, including administration of selective PTEN antagonist peptides, stimulates various degrees of axon regrowth in juvenile or adult rodents with central nervous system injuries. Im-portantly, post-injury PTEN suppression could enhance axonal growth and functional recovery in adult central nervous system after injury.

  14. Function of PTEN during the formation and maintenance of neuronal circuits in the brain.

    Science.gov (United States)

    van Diepen, Michiel T; Eickholt, Britta J

    2008-01-01

    PTEN (phosphatase and tensin homologue deleted on chromosome 10) is a tumor suppressor that can inhibit proliferation and migration and controls apoptosis in a number of cell types, mainly through inhibition of the phosphoinositide 3-kinase (PI3K) signaling pathway. Patients carrying inactivating mutations of PTEN show a prevalence to develop tumors that can coincide with neurological defects such as mental retardation, ataxia and seizures. A number of in vitro and in vivo studies were instrumental in uncovering a direct correlation between deregulated PI3K/PTEN signaling and changes in neuronal morphogenesis, which is likely to have profound bearings upon the pathogenesis of neurological symptoms. This review outlines recent work on the function of PTEN during vertebrate brain development and the current understanding of the signaling pathways downstream of PTEN that control neuronal connectivity in the brain.

  15. The Involvement of Phosphatase and Tensin Homolog Deleted on Chromosome Ten (PTEN in the Regulation of Inflammation Following Coronary Microembolization

    Directory of Open Access Journals (Sweden)

    Jiangyou Wang

    2014-06-01

    Full Text Available Background/Aims: Growing evidence shows that phosphatase and tensin homolog deleted on chromosome ten (PTEN is involved in regulating inflammation in different pathological conditions. Therefore, we hypothesized that the upregulation of PTEN correlates with the impairment of cardiac function in swine following coronary microembolization (CME. Methods: To possibly disclose an anti-inflammatory effect of PTEN, we induced swine CME by injecting inertia plastic microspheres (42 μm in diameter into the left anterior descending coronary artery and analyzed the myocardial tissue by immunochemistry, qRT-PCR and western blot analyses. In addition, we downregulated PTEN using siRNA. Results: Following CME, PTEN mRNA and protein levels were elevated as early as 3 h, peaked at 12 h, and then continuously decreased at 24 h and 48 h but remained elevated. Through linear correlation analysis, the PTEN protein level positively correlated with cTnI and TNF-α but was negatively correlated with LVEF. Furthermore, PTEN siRNA reduced the microinfarct volume, improved cardiac function (LVEF, reduced the release of cTnI, and suppressed PTEN and TNF-α protein expression. Conclusion: This study demonstrated, for the first time, that PTEN is involved in CME-induced inflammatory injury. The data generated from this study provide a rationale for the development of PTEN-based anti-inflammatory strategies.

  16. Low-dose effects of bisphenol A on mammary gland development in rats

    DEFF Research Database (Denmark)

    Egebjerg, Karen Mandrup; Boberg, Julie; Isling, Louise Krag

    2016-01-01

    Bisphenol A (BPA) is widely used in food contact materials, toys, and other products. Several studies have indicated that effects observed at doses near human exposure levels may not be observed at higher doses. Many studies have shown effects on mammary glands at low doses of BPA, however, because...

  17. In-Silico Genomic Approaches To Understanding Lactation, Mammary Development, And Breast Cancer

    Science.gov (United States)

    Lactation-related traits are influenced by genetics. From a quantitative standpoint, these traits have been well studied in dairy species, but there has also been work on the genetics of lactation in humans and mice. In addition, there is evidence to support the notion that other mammary gland trait...

  18. A study of the dynamics of PTEN proteins in living cells using in vivo fluorescence correlation spectroscopy

    Science.gov (United States)

    Du, Zhixue; Dong, Chaoqing; Ren, Jicun

    2017-06-01

    PTEN (phosphatase and tensin homolog on chromosome 10) is one of the most important tumor-suppressor proteins, which plays a key role in negative regulation of the PI3K/AKT pathway, and governs many cellular processes including growth, proliferation, survival and migration. The dynamics of PTEN proteins in single living cells is as yet unclear owing to a shortage of suitable in vivo approaches. Here, we report a single-molecule method for in vivo study of the dynamics of PTEN proteins in living cells using fluorescence correlation spectroscopy (FCS). First, we established a monoclonal H1299 stable cell line expressing enhanced green fluorescent protein (EGFP) and PTEN (EGFP-PTEN) fusion proteins; we then developed an in vivo FCS method to study the dynamics of EGFP-PTEN both in the nucleus and the cytoplasm. We investigated the diffusion behaviors of EGFP and EGFP-PTEN in solution, nucleus and cytosol, and observed that the motion of PTEN in living cells was restricted compared with EGFP. Finally, we investigated the protein dynamics in living cells under oxidative stress stimulation and a cellular ATP depletion treatment. Under oxidative stress stimulation, the EGFP-PTEN concentration increased in the nucleus, but slightly decreased in the cytoplasm. The diffusion coefficient and alpha value of EGFP-PTEN reduced significantly both in the nucleus and cytoplasm; the significantly decreased alpha parameter indicates a more restricted Brownian diffusion behavior. Under the cellular ATP depletion treatment, the concentration of EGFP-PTEN remained unchanged in the nucleus and decreased significantly in cytosol. The diffusion coefficient of EGFP-PTEN decreased significantly in cytosol, but showed no significant change in the nucleus; the alpha value decreased significantly in both the nucleus and cytoplasm. These results suggest that the concentration and mobility of PTEN in the nucleus and cytoplasm can be regulated by stimulation methods. Our approach provides a unique

  19. PELP1 overexpression in the mouse mammary gland results in the development of hyperplasia and carcinoma.

    Science.gov (United States)

    Cortez, Valerie; Samayoa, Cathy; Zamora, Andrea; Martinez, Lizatte; Tekmal, Rajeshwar R; Vadlamudi, Ratna K

    2014-12-15

    Estrogen receptor (ER) coregulator overexpression promotes carcinogenesis and/or progression of endocrine related-cancers in which steroid hormones are powerful mitogenic agents. Recent studies in our laboratory, as well as others, demonstrated that the estrogen receptor coregulator PELP1 is a proto-oncogene. PELP1 interactions with histone demethylase KDM1 play a critical role in its oncogenic functions and PELP1 is a prognostic indicator of decreased survival in patients with breast cancer. However, the in vivo significance of PELP1 deregulation during initiation and progression of breast cancer remains unknown. We generated an inducible, mammary gland-specific PELP1-expressing transgenic (Tg) mouse (MMTVrtTA-TetOPELP1). We found more proliferation, extensive side branching, and precocious differentiation in PELP1-overexpressing mammary glands than in control glands. Aged MMTVrtTA-TetOPELP1 Tg mice had hyperplasia and preneoplastic changes as early as 12 weeks, and ER-positive mammary tumors occurred at a latency of 14 to 16 months. Mechanistic studies revealed that PELP1 deregulation altered expression of a number of known ER target genes involved in cellular proliferation (cyclin D1, CDKs) and morphogenesis (EGFR, MMPs) and such changes facilitated altered mammary gland morphogenesis and tumor progression. Furthermore, PELP1 was hyper-phosphorylated at its CDK phosphorylation site, suggesting an autocrine loop involving the CDK-cyclin D1-PELP1 axis in promoting mammary tumorigenesis. Treatment of PELP1 Tg mice with a KDM1 inhibitor significantly reduced PELP1-driven hyperbranching, reversed alterations in cyclin D1 expression levels, and reduced CDK-driven PELP1 phosphorylation. These results further support the hypothesis that PELP1 deregulation has the potential to promote breast tumorigenesis in vivo and represent a novel model for future investigation into molecular mechanisms of PELP1-mediated tumorigenesis.

  20. In Vitro and In Vivo Effects of Tumor Suppressor Gene PTEN on Endometriosis: An Experimental Study

    Science.gov (United States)

    Lv, Juan; Zhu, Qiaoying; Jia, Xuemei; Yu, Ningzhu; Li, Qian

    2016-01-01

    Background Endometriosis can cause dysmenorrhea and infertility. Its pathogenesis has not yet been clarified and its treatment continues to pose enormous challenges. The protein tyrosine phosphatase (PTEN) gene is a tumor suppressor gene. The aim of this study was to investigate the role and significance of PTEN protein in the occurrence, development, and treatment of endometriosis through changes in apoptosis rate, cell cycle, and angiogenesis. Material/Methods PTEN was overexpressed and silenced in lentiviral vectors and inserted into primary endometrial cells. The changes in cell cycle and apoptosis in the different PTEN expression groups were evaluated using flow cytometry. Vessel growth mimicry was observed using 3-dimensional culture. A human-mouse chimeric endometriosis model was constructed using SCID mice. Hematoxylin and eosin staining and immunohistochemistry were used to detect pathological changes in ectopic endometrial tissues and the expression of VEGF protein in a human-mouse chimeric endometriosis mouse model. Results PTEN overexpression significantly increased apoptosis and inhibited the cell cycle compared with the silenced and control groups. Furthermore, cells expressing low PTEN levels were better able to undergo vasculogenic mimicry, and exhibited significantly increased angiogenesis compared to cells overexpressing PTEN. We found that ectopic foci were more easily formed in the endometrial tissue of SCID mice with low PTEN expression, and the VEGF expression in this group was relatively high. Conclusions PTEN inhibits the occurrence and development of endometriosis by regulating angiogenesis and the apoptosis and cell cycle of endometrial cells; therefore, we propose that the PTEN gene can be used to treat endometriosis. PMID:27744455

  1. Mice lacking pten in osteoblasts have improved intramembranous and late endochondral fracture healing.

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    Travis A Burgers

    Full Text Available The failure of an osseous fracture to heal (development of a non-union is a common and debilitating clinical problem. Mice lacking the tumor suppressor Pten in osteoblasts have dramatic and progressive increases in bone volume and density throughout life. Since fracture healing is a recapitulation of bone development, we investigated the process of fracture healing in mice lacking Pten in osteoblasts (Ocn-cre(tg/+;Pten(flox/flox . Mid-diaphyseal femoral fractures induced in wild-type and Ocn-cre(tg/+;Pten(flox/flox mice were studied via micro-computed tomography (µCT scans, biomechanical testing, histological and histomorphometric analysis, and protein expression analysis. Ocn-cre(tg/+;Pten(flox/flox mice had significantly stiffer and stronger intact bones relative to controls in all cohorts. They also had significantly stiffer healing bones at day 28 post-fracture (PF and significantly stronger healing bones at days 14, 21, and 28 PF. At day 7 PF, the proximal and distal ends of the Pten mutant calluses were more ossified. By day 28 PF, Pten mutants had larger and more mineralized calluses. Pten mutants had improved intramembranous bone formation during healing originating from the periosteum. They also had improved endochondral bone formation later in the healing process, after mature osteoblasts are present in the callus. Our results indicate that the inhibition of Pten can improve fracture healing and that the local or short-term use of commercially available Pten-inhibiting agents may have clinical application for enhancing fracture healing.

  2. Deletion of the nuclear localization sequences and C-terminus of PTHrP impairs embryonic mammary development but also inhibits PTHrP production.

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    Kata Boras-Granic

    Full Text Available Parathyroid hormone-related protein (PTHrP can be secreted from cells and interact with its receptor, the Type 1 PTH/PTHrP Receptor (PTHR1 in an autocrine, paracrine or endocrine fashion. PTHrP can also remain inside cells and be transported into the nucleus, where its functions are unclear, although recent experiments suggest that it may broadly regulate cell survival and senescence. Disruption of either the PTHrP or PTHR1 gene results in many abnormalities including a failure of embryonic mammary gland development in mice and in humans. In order to examine the potential functions of nuclear PTHrP in the breast, we examined mammary gland development in PTHrP (1-84 knock-in mice, which express a mutant form of PTHrP that lacks the C-terminus and nuclear localization signals and which can be secreted but cannot enter the nucleus. Interestingly, we found that PTHrP (1-84 knock-in mice had defects in mammary mesenchyme differentiation and mammary duct outgrowth that were nearly identical to those previously described in PTHrP-/- and PTHR1-/- mice. However, the mammary buds in PTHrP (1-84 knock-in mice had severe reductions in mutant PTHrP mRNA levels, suggesting that the developmental defects were due to insufficient production of PTHrP by mammary epithelial cells and not loss of PTHrP nuclear function. Examination of the effects of nuclear PTHrP in the mammary gland in vivo will require the development of alternative animal models.

  3. Deletion of the Nuclear Localization Sequences and C-Terminus of PTHrP Impairs Embryonic Mammary Development but also Inhibits PTHrP Production

    Science.gov (United States)

    Boras-Granic, Kata; Dann, Pamela; VanHouten, Joshua; Karaplis, Andrew; Wysolmerski, John

    2014-01-01

    Parathyroid hormone-related protein (PTHrP) can be secreted from cells and interact with its receptor, the Type 1 PTH/PTHrP Receptor (PTHR1) in an autocrine, paracrine or endocrine fashion. PTHrP can also remain inside cells and be transported into the nucleus, where its functions are unclear, although recent experiments suggest that it may broadly regulate cell survival and senescence. Disruption of either the PTHrP or PTHR1 gene results in many abnormalities including a failure of embryonic mammary gland development in mice and in humans. In order to examine the potential functions of nuclear PTHrP in the breast, we examined mammary gland development in PTHrP (1–84) knock-in mice, which express a mutant form of PTHrP that lacks the C-terminus and nuclear localization signals and which can be secreted but cannot enter the nucleus. Interestingly, we found that PTHrP (1–84) knock-in mice had defects in mammary mesenchyme differentiation and mammary duct outgrowth that were nearly identical to those previously described in PTHrP−/− and PTHR1−/− mice. However, the mammary buds in PTHrP (1–84) knock-in mice had severe reductions in mutant PTHrP mRNA levels, suggesting that the developmental defects were due to insufficient production of PTHrP by mammary epithelial cells and not loss of PTHrP nuclear function. Examination of the effects of nuclear PTHrP in the mammary gland in vivo will require the development of alternative animal models. PMID:24785493

  4. Genomic rearrangements of PTEN in prostate cancer

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    Sopheap ePhin

    2013-09-01

    Full Text Available The phosphatase and tensin homolog gene on chromosome 10q23.3 (PTEN is a negative regulator of the PIK3/Akt survival pathway and is the most frequently deleted tumor suppressor gene in prostate cancer. Monoallelic loss of PTEN is present in up to 60% of localized prostate cancers and complete loss of PTEN in prostate cancer is linked to metastasis and androgen independent progression. Studies on the genomic status of PTEN in prostate cancer initially used a two-color fluorescence in-situ hybridization (FISH assay for PTEN copy number detection in formalin fixed paraffin embedded tissue preparations. More recently, a four-color FISH assay containing two additional control probes flanking the PTEN locus with a lower false-positive rate was reported. Combined with the detection of other critical genomic biomarkers for prostate cancer such as ERG, AR, and MYC, the evaluation of PTEN genomic status has proven to be invaluable for patient stratification and management. Although less frequent than allelic deletions, point mutations in the gene and epigenetic silencing are also known to contribute to loss of PTEN function, and ultimately to prostate cancer initiation. Overall, it is clear that PTEN is a powerful biomarker for prostate cancer. Used as a companion diagnostic for emerging therapeutic drugs, FISH analysis of PTEN is promisingly moving human prostate cancer closer to more effective cancer management and therapies.

  5. Parathyroid hormone-related protein is not required for normal ductal or alveolar development in the post-natal mammary gland.

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    Kata Boras-Granic

    Full Text Available PTHrP is necessary for the formation of the embryonic mammary gland and, in its absence, the embryonic mammary bud fails to form the neonatal duct system. In addition, PTHrP is produced by the breast during lactation and contributes to the regulation of maternal calcium homeostasis during milk production. In this study, we examined the role of PTHrP during post-natal mammary development. Using a PTHrP-lacZ transgenic mouse, we surveyed the expression of PTHrP in the developing post-natal mouse mammary gland. We found that PTHrP expression is restricted to the basal cells of the gland during pubertal development and becomes expressed in milk secreting alveolar cells during pregnancy and lactation. Based on the previous findings that overexpression of PTHrP in cap and myoepithelial cells inhibited ductal elongation during puberty, we predicted that ablation of native PTHrP expression in the post-natal gland would result in accelerated ductal development. To address this hypothesis, we generated two conditional models of PTHrP-deficiency specifically targeted to the postnatal mammary gland. We used the MMTV-Cre transgene to ablate the floxed PTHrP gene in both luminal and myoepithelial cells and a tetracycline-regulated K14-tTA;tetO-Cre transgene to target PTHrP expression in just myoepithelial and cap cells. In both models of PTHrP ablation, we found that mammary development proceeds normally despite the absence of PTHrP. We conclude that PTHrP signaling is not required for normal ductal or alveolar development.

  6. Parathyroid hormone-related protein is not required for normal ductal or alveolar development in the post-natal mammary gland.

    Science.gov (United States)

    Boras-Granic, Kata; VanHouten, Joshua; Hiremath, Minoti; Wysolmerski, John

    2011-01-01

    PTHrP is necessary for the formation of the embryonic mammary gland and, in its absence, the embryonic mammary bud fails to form the neonatal duct system. In addition, PTHrP is produced by the breast during lactation and contributes to the regulation of maternal calcium homeostasis during milk production. In this study, we examined the role of PTHrP during post-natal mammary development. Using a PTHrP-lacZ transgenic mouse, we surveyed the expression of PTHrP in the developing post-natal mouse mammary gland. We found that PTHrP expression is restricted to the basal cells of the gland during pubertal development and becomes expressed in milk secreting alveolar cells during pregnancy and lactation. Based on the previous findings that overexpression of PTHrP in cap and myoepithelial cells inhibited ductal elongation during puberty, we predicted that ablation of native PTHrP expression in the post-natal gland would result in accelerated ductal development. To address this hypothesis, we generated two conditional models of PTHrP-deficiency specifically targeted to the postnatal mammary gland. We used the MMTV-Cre transgene to ablate the floxed PTHrP gene in both luminal and myoepithelial cells and a tetracycline-regulated K14-tTA;tetO-Cre transgene to target PTHrP expression in just myoepithelial and cap cells. In both models of PTHrP ablation, we found that mammary development proceeds normally despite the absence of PTHrP. We conclude that PTHrP signaling is not required for normal ductal or alveolar development.

  7. Dysregulation of synaptic plasticity precedes appearance of morphological defects in a Pten conditional knockout mouse model of autism.

    Science.gov (United States)

    Takeuchi, Koichi; Gertner, Michael J; Zhou, Jing; Parada, Luis F; Bennett, Michael V L; Zukin, R Suzanne

    2013-03-19

    The phosphoinositide signaling system is a crucial regulator of neural development, cell survival, and plasticity. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulates phosphatidylinositol 3-kinase signaling and downstream targets. Nse-Cre Pten conditional knockout mice, in which Pten is ablated in granule cells of the dentate gyrus and pyramidal neurons of the hippocampal CA3, but not CA1, recapitulate many of the symptoms of humans with inactivating PTEN mutations, including progressive hypertrophy of the dentate gyrus and deficits in hippocampus-based social and cognitive behaviors. However, the impact of Pten loss on activity-dependent synaptic plasticity in this clinically relevant mouse model of Pten inactivation remains unclear. Here, we show that two phosphatidylinositol 3-kinase- and protein synthesis-dependent forms of synaptic plasticity, theta burst-induced long-term potentiation and metabotropic glutamate receptor (mGluR)-dependent long-term depression, are dysregulated at medial perforant path-to-dentate gyrus synapses of young Nse-Cre Pten conditional knockout mice before the onset of visible morphological abnormalities. In contrast, long-term potentiation and mGluR-dependent long-term depression are normal at CA3-CA1 pyramidal cell synapses at this age. Our results reveal that deletion of Pten in dentate granule cells dysregulates synaptic plasticity, a defect that may underlie abnormal social and cognitive behaviors observed in humans with Pten inactivating mutations and potentially other autism spectrum disorders.

  8. Computational Analysis of PTEN Gene Mutation

    Directory of Open Access Journals (Sweden)

    Siew-Kien Mah

    2012-01-01

    Full Text Available Post-genomic data can be efficiently analyzed using computational tools. It has the advantage over the biochemical and biophysical methods in term of higher coverage. In this research, we adopted a computational analysis on PTEN gene mutation.  Mutation in PTEN is responsible for many human diseases. The results of this research provide insights into the protein domains of PTEN and the distribution of mutation.

  9. PPARγ, PTEN, and the Fight against Cancer

    OpenAIRE

    Teresi, Rosemary E.; Kristin A. Waite

    2008-01-01

    Peroxisome proliferator-activated receptor gamma (PPAR ) is a ligand-activated transcription factor, which belongs to the family of nuclear hormone receptors. Recent in vitro studies have shown that PPAR can regulate the transcription of phosphatase and tensin homolog on chromosome ten (PTEN), a known tumor suppressor. PTEN is a susceptibility gene for a number of disorders, including breast and thyroid cancer. Activation of PPAR through agonists increases functional PTEN protein levels...

  10. Prenatal exposure to BPA alters the epigenome of the rat mammary gland and increases the propensity to neoplastic development.

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    Eugen Dhimolea

    Full Text Available Exposure to environmental estrogens (xenoestrogens may play a causal role in the increased breast cancer incidence which has been observed in Europe and the US over the last 50 years. The xenoestrogen bisphenol A (BPA leaches from plastic food/beverage containers and dental materials. Fetal exposure to BPA induces preneoplastic and neoplastic lesions in the adult rat mammary gland. Previous results suggest that BPA acts through the estrogen receptors which are detected exclusively in the mesenchyme during the exposure period by directly altering gene expression, leading to alterations of the reciprocal interactions between mesenchyme and epithelium. This initiates a long sequence of altered morphogenetic events leading to neoplastic transformation. Additionally, BPA induces epigenetic changes in some tissues. To explore this mechanism in the mammary gland, Wistar-Furth rats were exposed subcutaneously via osmotic pumps to vehicle or 250 µg BPA/kg BW/day, a dose that induced ductal carcinomas in situ. Females exposed from gestational day 9 to postnatal day (PND 1 were sacrificed at PND4, PND21 and at first estrus after PND50. Genomic DNA (gDNA was isolated from the mammary tissue and immuno-precipitated using anti-5-methylcytosine antibodies. Detection and quantification of gDNA methylation status using the Nimblegen ChIP array revealed 7412 differentially methylated gDNA segments (out of 58207 segments, with the majority of changes occurring at PND21. Transcriptomal analysis revealed that the majority of gene expression differences between BPA- and vehicle-treated animals were observed later (PND50. BPA exposure resulted in higher levels of pro-activation histone H3K4 trimethylation at the transcriptional initiation site of the alpha-lactalbumin gene at PND4, concomitantly enhancing mRNA expression of this gene. These results show that fetal BPA exposure triggers changes in the postnatal and adult mammary gland epigenome and alters gene

  11. PTEN Mediates the Antioxidant Effect of Resveratrol at Nutritionally Relevant Concentrations

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    Marta Inglés

    2014-01-01

    Full Text Available Introduction. Antioxidant properties of resveratrol have been intensively studied for the last years, both in vivo and in vitro. Its bioavailability after an oral dose is very low and therefore it is very important to make sure that plasma concentrations of free resveratrol are sufficient enough to be active as antioxidant. Aims. In the present study, using nutritionally relevant concentrations of resveratrol, we aim to confirm its antioxidant capacity on reducing peroxide levels and look for the molecular pathway involved in this antioxidant effect. Methods. We used mammary gland tumor cells (MCF-7, which were pretreated with different concentrations of resveratrol for 48 h, and/or a PTEN inhibitor (bpV: bipy. Hydrogen peroxide levels were determined by fluorimetry, PTEN levels and Akt phosphorylation by Western Blotting, and mRNA expression of antioxidant genes by real-time reverse transcriptase-polymerase chain reaction (RT-PCR. Results. Resveratrol treatment for 48 h lowered peroxide levels in MCF-7, even at low nutritional concentrations (1 nM. This effect was mediated by the activation of PTEN/Akt pathway, which resulted in an upregulation of catalase and MnSOD mRNA levels. Conclusion. Resveratrol acts as an antioxidant at nutritionally relevant concentrations by inducing the expression of antioxidant enzymes, through a mechanism involving PTEN/Akt signaling pathway.

  12. Analysis of tumor heterogeneity and cancer gene networks using deep sequencing of MMTV-induced mouse mammary tumors.

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    Christiaan Klijn

    Full Text Available Cancer develops through a multistep process in which normal cells progress to malignant tumors via the evolution of their genomes as a result of the acquisition of mutations in cancer driver genes. The number, identity and mode of action of cancer driver genes, and how they contribute to tumor evolution is largely unknown. This study deployed the Mouse Mammary Tumor Virus (MMTV as an insertional mutagen to find both the driver genes and the networks in which they function. Using deep insertion site sequencing we identified around 31000 retroviral integration sites in 604 MMTV-induced mammary tumors from mice with mammary gland-specific deletion of Trp53, Pten heterozygous knockout mice, or wildtype strains. We identified 18 known common integration sites (CISs and 12 previously unknown CISs marking new candidate cancer genes. Members of the Wnt, Fgf, Fgfr, Rspo and Pdgfr gene families were commonly mutated in a mutually exclusive fashion. The sequence data we generated yielded also information on the clonality of insertions in individual tumors, allowing us to develop a data-driven model of MMTV-induced tumor development. Insertional mutations near Wnt and Fgf genes mark the earliest "initiating" events in MMTV induced tumorigenesis, whereas Fgfr genes are targeted later during tumor progression. Our data shows that insertional mutagenesis can be used to discover the mutational networks, the timing of mutations, and the genes that initiate and drive tumor evolution.

  13. Proliferative lesion of anogenital mammary-like glands in the setting of Cowden syndrome: case report and review of the literature.

    Science.gov (United States)

    Hedayat, Amin A; Pettus, Jason R; Marotti, Jonathan D; Tafe, Laura J; Holubar, Stefan D; Lisovsky, Mikhail

    2016-08-01

    Mammary-like glands are normal appendages of anogenital skin and can give rise to epithelial and stromal tumors that closely resemble breast tumors. Cowden syndrome is an autosomal-dominant cancer-predisposition syndrome that is associated with increased risk of various benign and malignant tumors including breast cancers. Here, we report the first case of a proliferative lesion of mammary-like glands in the setting of Cowden syndrome. A 27-year-old female with Cowden syndrome (R130Q-PTEN mutation) presented with a 1-cm tender, polypoid perianal lesion. An excisional biopsy revealed a circumscribed, lobulated lesion with fibromyxoid stroma and epithelial hyperplasia with apocrine and columnar cell changes that was arranged in papillary, micropapillary and focal cribriform architecture. The features strikingly resembled proliferative changes commonly seen in the breast. Interestingly, the patient subsequently developed an atypical complex sclerosing lesion of the breast. Given the increased risk of breast neoplasia in Cowden syndrome, and the morphologic relationship between breast glands and mammary-like glands, this case raises the possibility of an increased risk of neoplasia arising in mammary-like glands in the setting of Cowden syndrome.

  14. Correlation between PTEN Expression and PI3K/Akt Signal Pathway in Endometrial Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Qinglei GAO; Fei YE; Xi XIA; Hui XING; Yunping LU; Jianfeng ZHOU; Ding MA

    2009-01-01

    In order to investigate the role of the PTEN expression in carcinogenesis and develop-ment of endometrial carcinoma and clarify whether and how PTEN and PI3K/Akt pathway relate to endometrial carcinoma,the expression of PTEN and phospho-Akt was detected by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) methods and Western-blot from 24 cases of endomctrial carcinoma,10 cases of endometrial atypical hyperplasia,10 cases of endometrial hy-perplasia,and 10 cases of normal endometrium.SP immunohistochemical methods were used to measure levels of PTEN protein expression in following 5 study groups:31 cases of endometrium in proliferative phase,30 cases of endometrium in secretory phase,71 cases of endometrial hyperplasia,25 cases of atypical hyperplasia and 73 cases of endometrial carcinoma.Immunostaining score of PTEN was 3.39±0.15 in proliferative phase,1.90±0.21 in secretory phase,3.34~0.29 in endometrial hyperplasia,0.624±0.11 in atypical hyperplasia,and 0.74±0.19 in endometrial carcinoma,respectively.PTEN mRNA relative value in normal endometrium,endometrial hyperplasia,endometrial atypical hyperplasia,and endometrial carcinoma was 2.45±0.51,2.32±0.32,0.46±0.11,and 0.35±0.13 respec-tively.The expression levels of PTEN mRNA and protein in patients with endometrial carcinoma and atypical hyperplasia were significantly lower than in those of proliferative phase and with endo-metrial hyperplasia.The level of PTEN expression in patients with endometrial carcinoma was sig-nificantly related to tissue type (P0.05).Western blot analysis revealed that Phospho-Akt level in PTEN negative cases was significantly higher,and there was a negative correlation between PTEN and phospho-Akt (r=- 0.8973,P<0.0001).It was suggested that loss of PTEN expression was an early event in endometrial tumorigenesis.The phosphorylation of Akt induced by the loss of PTEN took part in the tumorigenesis and development of endometrial carcinoma.

  15. Development of new therapy for canine mammary cancer with recombinant measles virus

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    Koichiro Shoji

    2016-01-01

    Full Text Available Oncolytic virotherapy is a promising treatment strategy for cancer. We previously generated a recombinant measles virus (rMV-SLAMblind that selectively uses a poliovirus receptor-related 4 (PVRL4/Nectin4 receptor, but not signaling lymphocyte activation molecule (SLAM. We demonstrated that the virus exerts therapeutic effects against human breast cancer cells. Here, we examined the applicability of rMV-SLAMblind to treating canine mammary cancers (CMCs. We found that the susceptibilities of host cells to rMV-SLAMblind were dependent on canine Nectin-4 expression. Nectin-4 was detected in four of nine CMC cell lines. The rMV-SLAMblind efficiently infected those four Nectin-4-positive cell lines and was cytotoxic for three of them (CF33, CHMm, and CTBm. In vivo experiment showed that the administration of rMV-SLAMblind greatly suppressed the progression of tumors in mice xenografted with a CMC cell line (CF33. Immunohistochemistry revealed that canine Nectin-4 was expressed in 45% of canine mammary tumors, and the tumor cells derived from one clinical specimen were efficiently infected with rMV-SLAMblind. These results suggest that rMV-SLAMblind infects CMC cells and displays antitumor activity in vitro, in xenografts, and ex vivo. Therefore, oncolytic virotherapy with rMV-SLAMblind can be a novel method for treating CMCs.

  16. Loss of the BRCA1-interacting helicase BRIP1 results in abnormal mammary acinar morphogenesis.

    Directory of Open Access Journals (Sweden)

    Kazuhiro Daino

    Full Text Available BRIP1 is a DNA helicase that directly interacts with the C-terminal BRCT repeat of the breast cancer susceptibility protein BRCA1 and plays an important role in BRCA1-dependent DNA repair and DNA damage-induced checkpoint control. Recent studies implicate BRIP1 as a moderate/low-penetrance breast cancer susceptibility gene. However, the phenotypic effects of BRIP1 dysfunction and its role in breast cancer tumorigenesis remain unclear. To explore the function of BRIP1 in acinar morphogenesis of mammary epithelial cells, we generated BRIP1-knockdown MCF-10A cells by short hairpin RNA (shRNA-mediated RNA interference and examined its effect in a three-dimensional culture model. Genome-wide gene expression profiling by microarray and quantitative RT-PCR were performed to identify alterations in gene expression in BRIP1-knockdown cells compared with control cells. The microarray data were further investigated using the pathway analysis and Gene Set Enrichment Analysis (GSEA for pathway identification. BRIP1 knockdown in non-malignant MCF-10A mammary epithelial cells by RNA interference induced neoplastic-like changes such as abnormal cell adhesion, increased cell proliferation, large and irregular-shaped acini, invasive growth, and defective lumen formation. Differentially expressed genes, including MCAM, COL8A1, WIPF1, RICH2, PCSK5, GAS1, SATB1, and ELF3, in BRIP1-knockdown cells compared with control cells were categorized into several functional groups, such as cell adhesion, polarity, growth, signal transduction, and developmental process. Signaling-pathway analyses showed dysregulation of multiple cellular signaling pathways, involving LPA receptor, Myc, Wnt, PI3K, PTEN as well as DNA damage response, in BRIP1-knockdown cells. Loss of BRIP1 thus disrupts normal mammary morphogenesis and causes neoplastic-like changes, possibly via dysregulating multiple cellular signaling pathways functioning in the normal development of mammary glands.

  17. PTEN inhibits BMI1 function independently of its phosphatase activity

    Directory of Open Access Journals (Sweden)

    Kapoor Anil

    2009-11-01

    Full Text Available Abstract Background PTEN is the second most mutated tumor suppressor gene other than p53. It suppresses tumorigenesis by dephosphorylating phosphatidylinositol (3,4,5-triphosphate (PIP3 to phosphatidylinositol (4,5-biphosphate (PIP2, thereby directly inhibiting phosphatidylinositol 3 kinase (PI3K-mediated tumorigenic activities. Consistent with this model of action, cytosolic PTEN is recruited to the plasma membrane to dephosphorylate PIP3. While nuclear PTEN has been shown to suppress tumorigenesis by governing genome integrity, additional mechanisms may also contribute to nuclear PTEN-mediated tumor suppression. The nuclear protein BMI1 promotes stem cell self-renewal and tumorigenesis and PTEN inhibits these events, suggesting that PTEN may suppress BMI1 function. Results We investigated whether PTEN inhibits BMI1 function during prostate tumorigenesis. PTEN binds to BMI1 exclusively in the nucleus. This interaction does not require PTEN's phosphatase activity, as phosphatase-deficient PTEN mutants, PTEN/C124S (CS, PTEN/G129E (GE, and a C-terminal PTEN fragment (C-PTEN excluding the catalytic domain, all associate with BMI1. Furthermore, the residues 186-286 of C-PTEN are sufficient for binding to BMI1. This interaction reduces BMI1's function. BMI1 enhances hTERT activity and reduces p16INK4A and p14ARF expression. These effects were attenuated by PTEN, PTEN(CS, PTEN(GE, and C-PTEN. Furthermore, knockdown of PTEN in DU145 cells increased hTERT promoter activity, which was reversed when BMI1 was concomitantly knocked-down, indicating that PTEN reduces hTERT promoter activity via inhibiting BMI1 function. Conversely, BMI1 reduces PTEN's ability to inhibit AKT activation, which can be attributed to its interaction with PTEN in the nucleus, making PTEN unavailable to dephosphorylate membrane-bound PIP3. Furthermore, BMI1 appears to co-localize with PTEN more frequently in clinical prostate tissue samples from patients diagnosed with PIN

  18. The angiotensin receptor blocker, Losartan, inhibits mammary tumor development and progression to invasive carcinoma

    Science.gov (United States)

    Coulson, Rhiannon; Liew, Seng H.; Connelly, Angela A.; Yee, Nicholas S.; Deb, Siddhartha; Kumar, Beena; Vargas, Ana C.; O’Toole, Sandra A.; Parslow, Adam C.; Poh, Ashleigh; Putoczki, Tracy; Morrow, Riley J.; Alorro, Mariah; Lazarus, Kyren A.; Yeap, Evie F.W.; Walton, Kelly L.; Harrison, Craig A.; Hannan, Natalie J.; George, Amee J.; Clyne, Colin D.; Ernst, Matthias; Allen, Andrew M.; Chand, Ashwini L.

    2017-01-01

    Drugs that target the Renin-Angiotensin System (RAS) have recently come into focus for their potential utility as cancer treatments. The use of Angiotensin Receptor Blockers (ARBs) and Angiotensin-Converting Enzyme (ACE) Inhibitors (ACEIs) to manage hypertension in cancer patients is correlated with improved survival outcomes for renal, prostate, breast and small cell lung cancer. Previous studies demonstrate that the Angiotensin Receptor Type I (AT1R) is linked to breast cancer pathogenesis, with unbiased analysis of gene-expression studies identifying significant up-regulation of AGTR1, the gene encoding AT1R in ER+ve/HER2−ve tumors correlating with poor prognosis. However, there is no evidence, so far, of the functional contribution of AT1R to breast tumorigenesis. We explored the potential therapeutic benefit of ARB in a carcinogen-induced mouse model of breast cancer and clarified the mechanisms associated with its success. Mammary tumors were induced with 7,12-dimethylbenz[α]antracene (DMBA) and medroxyprogesterone acetate (MPA) in female wild type mice and the effects of the ARB, Losartan treatment assessed in a preventative setting (n = 15 per group). Tumor histopathology was characterised by immunohistochemistry, real-time qPCR to detect gene expression signatures, and tumor cytokine levels measured with quantitative bioplex assays. AT1R was detected with radiolabelled ligand binding assays in fresh frozen tumor samples. We showed that therapeutic inhibition of AT1R, with Losartan, resulted in a significant reduction in tumor burden; and no mammary tumor incidence in 20% of animals. We observed a significant reduction in tumor progression from DCIS to invasive cancer with Losartan treatment. This was associated with reduced tumor cell proliferation and a significant reduction in IL-6, pSTAT3 and TNFα levels. Analysis of tumor immune cell infiltrates, however, demonstrated no significant differences in the recruitment of lymphocytes or tumour

  19. PTEN, Longevity and Age-Related Diseases

    Directory of Open Access Journals (Sweden)

    Izak S. Tait

    2013-12-01

    Full Text Available Since the discovery of PTEN, this protein has been shown to be an effective suppressor of cancer and a contributor to longevity. This report will review, in depth, the associations between PTEN and other molecules, its mutations and regulations in order to present how PTEN can be used to increase longevity. This report will collect recent research of PTEN and use this to discuss PTEN’s role in caloric restriction, antioxidative defense of DNA-damage and the role it plays in suppressing tumors. The report will also discuss that variety of ways that PTEN can be compromised, through mutations, complete loss of alleles and its main antagonist, the PI3K/AKT pathway.

  20. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... understood. The mouse is a widely used model of mammary gland development, both directly by studying the mouse mammary epithelial cells themselves and indirectly, by studying development, morphogenesis, differentiation and carcinogenesis of xenotransplanted human breast epithelium in vivo. While in early...... studies, human or mouse epithelium was implanted as fragments into the mouse gland, more recent technical progress has allowed the self-renewal capacity and differentiation potential of distinct cell populations or even individual cells to be interrogated. Here, we review and discuss similarities...

  1. DNA Mismatch Repair Deficiency Accelerates Endometrial Tumorigenesis in Pten Heterozygous Mice

    OpenAIRE

    Hong WANG; Douglas, Wayne; Lia, Marie; Edelmann, Winfried; Kucherlapati, Raju; Podsypanina, Katrina; Parsons, Ramon; Ellenson, Lora Hedrick

    2002-01-01

    PTEN mutation and microsatellite instability are two of the most common genetic alterations in uterine endometrioid carcinoma. Furthermore, previous studies have suggested an association between the two alterations, however the basis and consequence of the association is not understood. Recently it has been shown that 100% of female Pten+/− mice develop complex atypical hyperplasia by 32 weeks of age that progresses to endometrial carcinoma in ∼20 to 25% of mice at 40 weeks. In an attempt to ...

  2. Connexins, E-cadherin, Claudin-7 and β-catenin transiently form junctional nexuses during the post-natal mammary gland development.

    Science.gov (United States)

    Dianati, Elham; Poiraud, Jérémy; Weber-Ouellette, Anne; Plante, Isabelle

    2016-08-01

    Gap junctions are intercellular channels made of connexins (Cxs) that allow direct communication between adjacent cells. Modulation of Cxs has been associated with abnormal development and function of the mammary gland and breast cancer. However, the mechanisms underlying their expression during normal mammary gland are not yet known. Cxs interact with components of tight and adherens junctions. Thus, we hypothesized that the expression levels of Cxs vary during mammary gland development and are regulated through stage-dependent interactions with members of the tight and adherens junctions. Our specific objectives were to: 1) determine the expression of Cxs and tight and adherens junction proteins throughout development and 2) characterize Cxs interactions with components of tight and adherens junctions. Murine mammary glands were sampled at various developmental stages (pre-pubescent to post-weaning). RT-qPCR and western-blot analyses demonstrated differential expression patterns for all gap (Cx43, Cx32, Cx26, Cx30), tight (Claudin-1, -3, -4, -7) and adherens (β-catenin, E- and P-cadherins) junctions throughout development. Interestingly, co-immunoprecipitation demonstrated interactions between these different types of junctions. Cx30 interacted with Cx26 just at the late pregnancy stage. While Cx43 showed a persistent interaction with β-catenin from virginity to post-weaning, its interactions with E-cadherin and Claudin-7 were transient. Cx32 interacted with Cx26, E-cadherin and β-catenin during lactation. Immunofluorescence results confirmed the existence of a junctional nexus that remodeled during mammary gland development. Together, our results confirm that the expression levels of Cxs vary concomitantly and that Cxs form junctional nexuses with tight and adherens junctions, suggesting the existence of common regulatory pathways.

  3. Poly-ADP ribosylation of PTEN by tankyrases promotes PTEN degradation and tumor growth

    Science.gov (United States)

    Li, Nan; Zhang, Yajie; Han, Xin; Liang, Ke; Wang, Jiadong; Feng, Lin; Wang, Wenqi; Songyang, Zhou; Lin, Chunru; Yang, Liuqing; Yu, Yonghao

    2015-01-01

    PTEN [phosphatidylinositol (3,4,5)-trisphosphate phosphatase and tensin homolog deleted from chromosome 10], a phosphatase and critical tumor suppressor, is regulated by numerous post-translational modifications, including phosphorylation, ubiquitination, acetylation, and SUMOylation, which affect PTEN localization and protein stability. Here we report ADP-ribosylation as a new post-translational modification of PTEN. We identified PTEN as a novel substrate of tankyrases, which are members of the poly(ADP-ribose) polymerases (PARPs). We showed that tankyrases interact with and ribosylate PTEN, which promotes the recognition of PTEN by a PAR-binding E3 ubiquitin ligase, RNF146, leading to PTEN ubiquitination and degradation. Double knockdown of tankyrase1/2 stabilized PTEN, resulting in the subsequent down-regulation of AKT phosphorylation and thus suppressed cell proliferation and glycolysis in vitro and tumor growth in vivo. Furthermore, tankyrases were up-regulated and negatively correlated with PTEN expression in human colon carcinomas. Together, our study revealed a new regulation of PTEN and highlighted a role for tankyrases in the PTEN–AKT pathway that can be explored further for cancer treatment. PMID:25547115

  4. Vitamin D and the mammary gland: a review on its role in normal development and breast cancer.

    Science.gov (United States)

    Lopes, Nair; Paredes, Joana; Costa, José Luis; Ylstra, Bauke; Schmitt, Fernando

    2012-05-31

    Breast cancer is a heterogeneous disease associated with diverse biological behaviours and clinical outcome. Although some molecular subgroups of breast cancer have a targeted therapy, the most aggressive tumours still lack a molecular target. Despite vitamin D being classically associated with the physiological role of calcium regulation and phosphate transport in bone metabolism, several studies have demonstrated a wide range of functions for this hormone, which are particularly important in the field of cancer. The mechanisms underlying the protective actions of vitamin D in cancer development are only sparsely understood, but evidence shows that vitamin D participates in cell growth regulation, apoptosis and cell differentiation. In addition, it has been implicated in the suppression of cancer cell invasion, angiogenesis and metastasis. Most of vitamin D biological actions are mediated by the vitamin D receptor and the synthesis and catabolism of this hormone are regulated by the enzymes CYP27B1 and CYP24A1. In the present review we highlight research data concerning the function of this hormone in the mammary gland, with a special focus on breast carcinogenesis. Hence, and although the available data are controversial, we consider not only updated information on the epidemiology of vitamin D in breast cancer and its potential value as a therapeutic agent or prophylactic (with an emphasis on molecular mechanisms and effectors of vitamin D action), but include data on its role in other stages of breast cancer progression as well. Accordingly, we review data on the influence of vitamin D in the development of normal breast and the expression of vitamin D-related proteins (VDR, CYP27B1 and CYP24A21) in benign mammary lesions and ductal carcinomas in situ.

  5. Jnk2 effects on tumor development, genetic instability and replicative stress in an oncogene-driven mouse mammary tumor model.

    Directory of Open Access Journals (Sweden)

    Peila Chen

    Full Text Available Oncogenes induce cell proliferation leading to replicative stress, DNA damage and genomic instability. A wide variety of cellular stresses activate c-Jun N-terminal kinase (JNK proteins, but few studies have directly addressed the roles of JNK isoforms in tumor development. Herein, we show that jnk2 knockout mice expressing the Polyoma Middle T Antigen transgene developed mammary tumors earlier and experienced higher tumor multiplicity compared to jnk2 wildtype mice. Lack of jnk2 expression was associated with higher tumor aneuploidy and reduced DNA damage response, as marked by fewer pH2AX and 53BP1 nuclear foci. Comparative genomic hybridization further confirmed increased genomic instability in PyV MT/jnk2-/- tumors. In vitro, PyV MT/jnk2-/- cells underwent replicative stress and cell death as evidenced by lower BrdU incorporation, and sustained chromatin licensing and DNA replication factor 1 (CDT1 and p21(Waf1 protein expression, and phosphorylation of Chk1 after serum stimulation, but this response was not associated with phosphorylation of p53 Ser15. Adenoviral overexpression of CDT1 led to similar differences between jnk2 wildtype and knockout cells. In normal mammary cells undergoing UV induced single stranded DNA breaks, JNK2 localized to RPA (Replication Protein A coated strands indicating that JNK2 responds early to single stranded DNA damage and is critical for subsequent recruitment of DNA repair proteins. Together, these data support that JNK2 prevents replicative stress by coordinating cell cycle progression and DNA damage repair mechanisms.

  6. A common variation of the PTEN gene is associated with peripheral insulin resistance

    DEFF Research Database (Denmark)

    Grinder-Hansen, L; Ribel-Madsen, R; Wojtaszewski, Jørgen

    2016-01-01

    . RESULTS: The minor G allele of PTEN rs11202614 was associated with elevated fasting plasma insulin levels and a decreased peripheral glucose disposal rate, but not with the hepatic insulin resistance index or insulin secretion measured as the first-phase insulin response and disposition index. The single...... nucleotide polymorphism was not associated with either PI3K or Akt activities. CONCLUSION: A common PTEN variation is associated with peripheral insulin resistance and subsequent risk of developing T2D. However, the association with insulin resistance is not explained by decreased proximal insulin signalling......AIM: Phosphatase and tensin homologue (PTEN) reduces insulin sensitivity by inhibiting the phosphatidylinositol 3-kinase (PI3K)/v-akt murine thymoma viral oncogene homologue (Akt) pathway. This study investigated how a common single nucleotide polymorphism near PTEN, previously associated...

  7. Expression and significance of PTEN and PCNA in human laryngeal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    李长青; 文莲姬; 金春顺; 崔树勋

    2004-01-01

    Objective: To elucidate the expression and significance of PTEN and PCNA in human laryngeal squamous cell carcinoma. Methods: Immunochemical method was used to study 60 cases of laryngeal carcinoma, 20 cases of normal laryngeal tissues which were closely adjacent to carcinoma and 10 cases of normal laryngeal tissues. Results: It was showed that PTEN gene was expressed in 85 % laryngeal carcinoma tissues. The percentage of lymph node metastasis of laryngeal carcinoma which were negative or positive of PTEN protein was 77.8 % and 33.3 % respectively, and the difference was significance ( P < 0.05). Conclusion: Expression of PTEN in laryngeal carcinoma was different from that of normal laryngeal tissues. It may play a role but not important in the tumorigenesis and development of laryngeal carcinoma.

  8. Expression of prolactin receptors in normal canine mammary tissue, canine mammary adenomas and mammary adenocarcinomas

    Directory of Open Access Journals (Sweden)

    Michel Erika

    2012-05-01

    Full Text Available Abstract Background Mammary tumors represent the most common neoplastic disease in female dogs. Recently, the promoting role of prolactin (PRL in the development of human breast carcinoma has been shown. Possible proliferative, anti-apoptotic, migratory and angiogenic effects of PRL on human mammary cancer cells in vitro and in vivo were suggested. The effects of PRL are mediated by its receptor, and alterations in receptor expression are likely to play a role in tumor development. Currently, not much data is available about prolactin receptor (PRLR expression in canine mammary tumors. To set the basis for investigations on the role of PRL in mammary tumorigenesis in this species, prolactin receptor expression was evaluated by semi-quantitative real time PCR and immunohistochemistry on 10 formalin-fixed, paraffin-embedded samples each of canine non-neoplastic mammary tissue, mammary adenomas and adenocarcinomas. Results The highest PRLR expression levels were found in normal mammary tissue, while adenomas, and to an even higher degree adenocarcinomas, showed a significant decrease in prolactin receptor expression. Compared to normal tissue, PRLR mRNA was reduced 2.4 fold (p = 0.0261 in adenomas and 4.8 fold (p = 0.008 in adenocarcinomas. PRLR mRNA expression was significantly lower in malignant than in benign lesions (p = 0.0165. Immunohistochemistry demonstrated PRLR expression in all three tissue types with signals mostly limited to epithelial cells. Conclusions Malignant transformation of mammary tissue was associated with a decline in prolactin receptor expression. Further studies are warranted to address the functional significance of this finding.

  9. PTEN, a widely known negative regulator of insulin/PI3K signaling, positively regulates neuronal insulin resistance

    Science.gov (United States)

    Gupta, Amit; Dey, Chinmoy Sankar

    2012-01-01

    Lipid and protein tyrosine phosphatase, phosphatase and tension homologue (PTEN), is a widely known negative regulator of insulin/phosphoinositide 3-kinase signaling. Down-regulation of PTEN is thus widely documented to ameliorate insulin resistance in peripheral tissues such as skeletal muscle and adipose. However, not much is known about its exact role in neuronal insulin signaling and insulin resistance. Moreover, alterations of PTEN in neuronal systems have led to discovery of several unexpected outcomes, including in the neurodegenerative disorder Alzheimer's disease (AD), which is increasingly being recognized as a brain-specific form of diabetes. In addition, contrary to expectations, its neuron-specific deletion in mice resulted in development of diet-sensitive obesity. The present study shows that PTEN, paradoxically, positively regulates neuronal insulin signaling and glucose uptake. Its down-regulation exacerbates neuronal insulin resistance. The positive role of PTEN in neuronal insulin signaling is likely due to its protein phosphatase actions, which prevents the activation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK), the kinases critically involved in neuronal energy impairment and neurodegeneration. Results suggest that PTEN acting through FAK, the direct protein substrate of PTEN, prevents ERK activation. Our findings provide an explanation for unexpected outcomes reported earlier with PTEN alterations in neuronal systems and also suggest a novel molecular pathway linking neuronal insulin resistance and AD, the two pathophysiological states demonstrated to be closely linked. PMID:22875989

  10. Canine mammary tumors - clinical survey

    Directory of Open Access Journals (Sweden)

    Elena Atanaskova Petrov

    2014-10-01

    Full Text Available Mammary tumours are the second most frequent neoplasia in dogs, mainly affecting older female patients. Approximately 50% of the mammary tumours are malignant with high percentage of mortality if not treated in time. The aim of this study was to analyze the data of canine patients with mammary tumours, to evaluate the type of tumours, as well as the relationship between tumour incidence and dogs’ age, reproductive cycle and sterilization. The survey was used to retrieve the information in the period of two years from the patient data base of the University Veterinary Hospital at the Faculty of Veterinary medicine in Skopje. Patients included in this survey were subjected to routine clinical investigation and additional laboratory tests (cytological examination, x-rays imaging, CBC and biochemical profile, histopathology of the tumor samples. Aged female patients (12 – 13 years are the most susceptible category for development of mammary tumours. The reproductive history showed that five of the patients with malignant mammary tumourshave never whelped and were not treated with any exogenous hormones. Malignant tumours (adenocarcinoma were diagnosed in 90% of the patients. Three patients died due to lung metastasis. Late diagnosis is one of the major problems that results in lethal outcome due to lung metastases. Since ovarian steroids play an important role in the aetiology, the most effective prevention of mammary tumoursis elective ovariectomy of the bitch at an early age.

  11. Differential Contribution of Acute and Chronic Inflammation to the Development of Murine Mammary 4T1 Tumors.

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    Celso Tarso Rodrigues Viana

    Full Text Available Based on the notion that inflammation favors tumorigenesis, our experiments comparatively assessed the influence of acute and chronic inflammation on the development of a murine mammary tumor (4T1. In addition, we characterized angiogenic and inflammatory markers in the tumor tissue and systemically. Subcutaneous implantation of polyether-polyurethane sponge discs in Balb/c mice was used to host 4T1 tumor cells (1x10(6, which were inoculated intraimplant 24 h or 10 days post implantation. Flow cytometric analysis of enzyme-digested implants revealed that, after 24 hours, the population of leukocytes was primarily characterized by neutrophils (42.53% +/- 8.45 and monocytes (37.53% +/- 7.48, with some lymphocytes (16.27% +/- 4.0 and a few dendritic cells (1.82% +/- 0.36. At 10 days, macrophages were predominant (37.10% +/- 4.54, followed by lymphocytes (28.1% +/- 4.77, and monocytes (22.33% +/- 3.05, with some dendritic cells (13.60% +/- 0.55 and neutrophils (11.07% +/- 2.27. A mammary tumor grown in a chronic inflammatory environment was 2-fold when compared with one grown in acute inflammation and 5-fold when compared with tumor alone. The levels of pro-angiogenic cytokine (VEGF-Vascular Endothelial Growth Factor were higher in implant-bearing tumor when 4T1 cells were grown in 10-day old implants as compared to the VEGF levels of the two other groups. Overall, the levels of the inflammatory markers evaluated (NAG -N-acetylglucosaminidase, TNF-α-Tumor Necrosis Factor-α were higher in both groups of implant-bearing tumors and in serum from those animals when compared with the tumor alone levels. This inflammation-related difference in tumor growth may provide new insights into the contribution of different inflammatory cell populations to cancer progression.

  12. Glioma cell VEGFR-2 confers resistance to chemotherapeutic and antiangiogenic treatments in PTEN-deficient glioblastoma.

    Science.gov (United States)

    Kessler, Tobias; Sahm, Felix; Blaes, Jonas; Osswald, Matthias; Rübmann, Petra; Milford, David; Urban, Severino; Jestaedt, Leonie; Heiland, Sabine; Bendszus, Martin; Hertenstein, Anne; Pfenning, Philipp-Niclas; Ruiz de Almodóvar, Carmen; Wick, Antje; Winkler, Frank; von Deimling, Andreas; Platten, Michael; Wick, Wolfgang; Weiler, Markus

    2015-10-13

    Loss of the tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a prerequisite for tumor cell-specific expression of vascular endothelial growth factor receptor (VEGFR)-2 in glioblastoma defining a subgroup prone to develop evasive resistance towards antiangiogenic treatments. Immunohistochemical analysis of human tumor tissues showed VEGFR-2 expression in glioma cells in 19% of specimens examined, mainly in the infiltration zone. Glioma cell VEGFR-2 positivity was restricted to PTEN-deficient tumor specimens. PTEN overexpression reduced VEGFR-2 expression in vitro, as well as knock-down of raptor or rictor. Genetic interference with VEGFR-2 revealed proproliferative, antiinvasive and chemoprotective functions for VEGFR-2 in glioma cells. VEGFR-2-dependent cellular effects were concomitant with activation of 'kappa-light-chain-enhancer' of activated B-cells, protein kinase B, and N-myc downstream regulated gene 1. Two-photon in vivo microscopy revealed that expression of VEGFR-2 in glioma cells hampers antiangiogenesis. Bevacizumab induces a proinvasive response in VEGFR-2-positive glioma cells. Patients with PTEN-negative glioblastomas had a shorter survival after initiation of bevacizumab therapy compared with PTEN-positive glioblastomas. Conclusively, expression of VEGFR-2 in glioma cells indicates an aggressive glioblastoma subgroup developing early resistance to temozolomide or bevacizumab. Loss of PTEN may serve as a biomarker identifying those tumors upfront by routine neuropathological methods.

  13. MicroRNA-152 regulates DNA methyltransferase 1 and is involved in the development and lactation of mammary glands in dairy cows.

    Directory of Open Access Journals (Sweden)

    Jie Wang

    Full Text Available MicroRNAs (miRNAs are a class of small non-coding, endogenous regulatory RNAs that function by controlling gene expression at the post-transcriptional level. Using small RNA sequencing and qRT-PCR techniques, we found that the expression of miR-152 was significantly increased during lactation in the mammary glands of dairy cows producing high quality milk compared with that in cows producing low quality milk. Furthermore, DNA methyltransferase 1 (DNMT1, which is a target of miR-152, was inversely correlated with the expression levels of miR-152 in the mammary glands of dairy cows. Dairy cow mammary epithelial cells (DCMECs were used as in vitro cell models to study the function of miR-152. The forced expression of miR-152 in DCMECs resulted in a marked reduction of DNMT1 at both mRNA and protein levels. This in turn led to a decrease in global DNA methylation and increased the expression of two lactation-related genes, serine/threonine protein kinase Akt (Akt and peroxisome proliferator-activated receptor gamma (Pparγ. In contrast, inhibition of miR-152 showed the opposite results. By using an electronic Coulter counter (CASY-TT and flow cytometer, we discovered that miR-152 enhanced the viability and multiplication capacity of DCMECs. In conclusion, miR-152 plays an important role in the development and lactation processes in the mammary glands of dairy cows. Our data provide insights into dairy cow mammary gland development and lactation.

  14. PTEN in liver diseases and cancer

    Institute of Scientific and Technical Information of China (English)

    Marion; Peyrou; Lucie; Bourgoin; Michelangelo; Foti

    2010-01-01

    The phosphoinositide 3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/Akt axis is a key signal transduction node that regulates crucial cellular functions, including insulin and other growth factors signaling, lipid and glucose metabolism, as well as cell survival and apoptosis. In this pathway, PTEN acts as a phosphoinositide phosphatase, which terminates PI3Kpropagated signaling by dephosphorylating PtdIns(3,4)P2 and PtdIns(3,4,5)P3. However, the role of PTEN does not appear to be restricted only to ...

  15. Development of a subset of forelimb muscles and their attachment sites requires the ulnar-mammary syndrome gene Tbx3

    Directory of Open Access Journals (Sweden)

    Mary P. Colasanto

    2016-11-01

    Full Text Available In the vertebrate limb over 40 muscles are arranged in a precise pattern of attachment via muscle connective tissue and tendon to bone and provide an extensive range of motion. How the development of somite-derived muscle is coordinated with the development of lateral plate-derived muscle connective tissue, tendon and bone to assemble a functional limb musculoskeletal system is a long-standing question. Mutations in the T-box transcription factor, TBX3, have previously been identified as the genetic cause of ulnar-mammary syndrome (UMS, characterized by distinctive defects in posterior forelimb bones. Using conditional mutagenesis in mice, we now show that TBX3 has a broader role in limb musculoskeletal development. TBX3 is not only required for development of posterior forelimb bones (ulna and digits 4 and 5, but also for a subset of posterior muscles (lateral triceps and brachialis and their bone eminence attachment sites. TBX3 specification of origin and insertion sites appears to be tightly linked with whether these particular muscles develop and may represent a newly discovered mechanism for specification of anatomical muscles. Re-examination of an individual with UMS reveals similar previously unrecognized muscle and bone eminence defects and indicates a conserved role for TBX3 in regulating musculoskeletal development.

  16. Mammary hypertrophy in an ovariohysterectomized cat.

    Science.gov (United States)

    Pukay, B P; Stevenson, D A

    1983-05-01

    A four year old ovariohysterectomized domestic short-haired cat under treatment for behavioral urine spraying and idiopathic alopecia developed mammary gland hypertrophy following treatment with megestrol acetate. Withdrawal of the progestin and treatment with androgen failed to cause regression of the hypertrophy. The affected mammary gland was surgically excised and recovery was uneventful.

  17. Does cancer start in the womb? altered mammary gland development and predisposition to breast cancer due to in utero exposure to endocrine disruptors.

    Science.gov (United States)

    Soto, Ana M; Brisken, Cathrin; Schaeberle, Cheryl; Sonnenschein, Carlos

    2013-06-01

    We are now witnessing a resurgence of theories of development and carcinogenesis in which the environment is again being accepted as a major player in phenotype determination. Perturbations in the fetal environment predispose an individual to disease that only becomes apparent in adulthood. For example, gestational exposure to diethylstilbestrol resulted in clear cell carcinoma of the vagina and breast cancer. In this review the effects of the endocrine disruptor bisphenol-A (BPA) on mammary development and tumorigenesis in rodents is used as a paradigmatic example of how altered prenatal mammary development may lead to breast cancer in humans who are also widely exposed to it through plastic goods, food and drink packaging, and thermal paper receipts. Changes in the stroma and its extracellular matrix led to altered ductal morphogenesis. Additionally, gestational and lactational exposure to BPA increased the sensitivity of rats and mice to mammotropic hormones during puberty and beyond, thus suggesting a plausible explanation for the increased incidence of breast cancer.

  18. PTEN degradation after ischemic stroke: a double-edged sword.

    Science.gov (United States)

    Li, W; Huang, R; Chen, Z; Yan, L-J; Simpkins, J W; Yang, S-H

    2014-08-22

    Tumor suppressor phosphatase and tensin homolog (PTEN) is highly expressed in neurons and PTEN inhibition has been reported to be neuroprotective against ischemic stroke in experimental models. On the other hand, PTEN deletion has been shown to lead to cognitive impairment. In the current study, we examined the expression and functions of PTEN in an ischemic stroke rodent model. We found rapid S-nitrosylation and degradation of PTEN after cerebral ischemia/reperfusion injury. PTEN degradation leads to activation of Akt. PTEN partial deletion or PTEN inhibition increased the expression of GABAA receptor (GABAAR) γ2 subunit and enhanced GABAA receptor current. After cerebral ischemia, increased expression of GABAAR γ2 subunit was observed in the ischemia region and the penumbra area. We also observed PTEN loss in astrocytes after cerebral ischemia. Astrocytic PTEN partial knockout increased astrocyte activation and exacerbated ischemic damage. We speculated that ischemic stroke induced neuronal PTEN degradation, hence enhanced GABAA receptor-medicated neuronal activity inhibition which could attenuate excitotoxicity and provide neuroprotection during the acute phase after stroke, while inhibiting long-term functional recovery and contributing to vascular cognitive impairment after stroke. On the other hand, ischemic stroke induced astrocytic PTEN loss and enhanced ischemic damage and astrogliosis. Taken together, our study indicates that ischemic stroke induces rapid PTEN degradation in both neurons and astrocytes which play both protective and detrimental action in a spatiotemporal- and cell-type-dependent manner. Our study provides critical insight for targeting PTEN signaling pathway for stroke treatment.

  19. Glandular epithelial AR inactivation enhances PTEN deletion-induced uterine pathology.

    Science.gov (United States)

    Choi, Jaesung Peter; Zheng, Yu; Handelsman, David J; Simanainen, Ulla

    2016-05-01

    Phosphatase and tensin homolog (PTEN) deletion induces uterine pathology, whereas androgen actions via androgen receptor (AR) support uterine growth and therefore may modify uterine cancer risk. We hypothesized that the androgen actions mediated via uterine glandular epithelial AR could modify PTEN deletion-induced uterine pathology. To test our hypothesis, we developed uterine glandular epithelium-specific PTEN and/or AR knockout mouse models comparing the uterine pathology among wild-type (WT), glandular epithelium-specific AR inactivation (ugeARKO), PTEN deletion (ugePTENKO), and the combined PTEN and AR knockout (ugePTENARKO) female mice. The double knockout restricted to glandular epithelium showed that AR inactivation enhanced PTEN deletion-induced uterine pathology with development of intraepithelial neoplasia by 20 weeks of age. In ugePTENARKO, 6/10 (60%) developed intraepithelial neoplasia, whereas 3/10 (30%) developed only glandular hyperplasia in ugePTENKO uterus. No uterine pathology was observed in WT (n=8) and ugeARKO (n=7) uteri. Uterine weight was significantly (P=0.002) increased in ugePTENARKO (374±97 mg (mean±s.e.)) compared with WT (97±6 mg), ugeARKO (94±12 mg), and ugePTENKO (205±33 mg). Estrogen receptor alpha (ERα) and P-AKT expression was modified by uterine pathology but did not differ between ugePTENKO and ugePTENARKO, suggesting that its expressions are not directly affected by androgens. However, progesterone receptor (PR) expression was reduced in ugePTENARKO compared to ugePTENKO uterus, suggesting that PR expression could be regulated by glandular epithelial AR inactivation. In conclusion, glandular epithelial AR inactivation (with persistent stromal AR action) enhanced PTEN deletion-induced uterine pathology possibly by downregulating PR expression in the uterus.

  20. Identification of novel PTEN-binding partners: PTEN interaction with fatty acid binding protein FABP4.

    Science.gov (United States)

    Gorbenko, O; Panayotou, G; Zhyvoloup, A; Volkova, D; Gout, I; Filonenko, V

    2010-04-01

    PTEN is a tumor suppressor with dual protein and lipid-phosphatase activity, which is frequently deleted or mutated in many human advanced cancers. Recent studies have also demonstrated that PTEN is a promising target in type II diabetes and obesity treatment. Using C-terminal PTEN sequence in pEG202-NLS as bait, yeast two-hybrid screening on Mouse Embryo, Colon Cancer, and HeLa cDNA libraries was carried out. Isolated positive clones were validated by mating assay and identified through automated DNA sequencing and BLAST database searches. Sequence analysis revealed a number of PTEN-binding proteins linking this phosphatase to a number of different signaling cascades, suggesting that PTEN may perform other functions besides tumor-suppressing activity in different cell types. In particular, the interplay between PTEN function and adipocyte-specific fatty-acid-binding protein FABP4 is of notable interest. The demonstrable tautology of PTEN to FABP4 suggested a role for this phosphatase in the regulation of lipid metabolism and adipocyte differentiation. This interaction was further studied using coimmunoprecipitation and gel-filtration assays. Finally, based on Biacore assay, we have calculated the K(D) of PTEN-FABP4 complex, which is around 2.8 microM.

  1. A prognosis classifier for breast cancer based on conserved gene regulation between mammary gland development and tumorigenesis: a multiscale statistical model.

    Science.gov (United States)

    Tian, Yingpu; Chen, Baozhen; Guan, Pengfei; Kang, Yujia; Lu, Zhongxian

    2013-01-01

    Identification of novel cancer genes for molecular therapy and diagnosis is a current focus of breast cancer research. Although a few small gene sets were identified as prognosis classifiers, more powerful models are still needed for the definition of effective gene sets for the diagnosis and treatment guidance in breast cancer. In the present study, we have developed a novel statistical approach for systematic analysis of intrinsic correlations of gene expression between development and tumorigenesis in mammary gland. Based on this analysis, we constructed a predictive model for prognosis in breast cancer that may be useful for therapy decisions. We first defined developmentally associated genes from a mouse mammary gland epithelial gene expression database. Then, we found that the cancer modulated genes were enriched in this developmentally associated genes list. Furthermore, the developmentally associated genes had a specific expression profile, which associated with the molecular characteristics and histological grade of the tumor. These result suggested that the processes of mammary gland development and tumorigenesis share gene regulatory mechanisms. Then, the list of regulatory genes both on the developmental and tumorigenesis process was defined an 835-member prognosis classifier, which showed an exciting ability to predict clinical outcome of three groups of breast cancer patients (the predictive accuracy 64∼72%) with a robust prognosis prediction (hazard ratio 3.3∼3.8, higher than that of other clinical risk factors (around 2.0-2.8)). In conclusion, our results identified the conserved molecular mechanisms between mammary gland development and neoplasia, and provided a unique potential model for mining unknown cancer genes and predicting the clinical status of breast tumors. These findings also suggested that developmental roles of genes may be important criteria for selecting genes for prognosis prediction in breast cancer.

  2. Quantitative and dynamic analysis of PTEN phosphorylation by NMR.

    Science.gov (United States)

    Cordier, Florence; Chaffotte, Alain; Wolff, Nicolas

    2015-05-01

    The dual lipid and protein phosphatase PTEN is a tumor suppressor controlling key biological processes, such as cell growth, proliferation and neuro-survival. Its activity and intracellular trafficking is finely regulated notably by multi-site phosphorylation of its C-terminal tail. The reversible and highly dynamic character of these regulatory events confers a temporal dimension to the cell for triggering crucial decisions. In this review, we describe how a recently developed time-resolved NMR spectroscopy approach unveils the dynamic establishment of the phosphorylation events of PTEN C-terminal tail controlled by CK2 and GSK3β kinases. Two cascades of reactions have been identified, in vitro and in extracts of human neuroblastoma cells. They are triggered independently on two nearby clusters of sites (S380-S385 and S361-S370) and occur on different timescales. In each cascade, the reactions follow an ordered model with a distributive kinetic mechanism. The vision of these cascades as two delay timers activating distinct or time-delayed regulatory responses gives a temporal dimension on PTEN regulation and is discussed in relation to the known functional roles of each cluster. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Role of PTEN in TNFα induced insulin resistance

    Energy Technology Data Exchange (ETDEWEB)

    Bulger, David A. [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Wellcome Trust Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ (United Kingdom); National Institute of Diabetes & Digestive & Kidney Disease, National Institutes of Health, Bethesda, MD 20892 (United States); Conley, Jermaine [Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Conner, Spencer H.; Majumdar, Gipsy [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Solomon, Solomon S., E-mail: ssolomon@uthsc.edu [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States)

    2015-06-05

    Aims/hypothesis: PTEN may play a reversible role in TNFα induced insulin resistance, which has been linked to obesity-associated insulin resistance (IR). Methods: Western blots for PTEN and p-Akt were performed on H-411E liver cells incubated with insulin, TNFα, and in selected experiments VO-OHpic vanadium complex in the presence and absence of PTEN siRNA. Total PTEN was compared to β-actin loading control and p-Akt was compared to total Akt. Results: Western blot and Real Time RT-PCR experiments showed increased PTEN after TNFα treatment (p = 0.04); slightly decreased PTEN after insulin treatment; and slightly increased PTEN after insulin + TNFα treatment. PTEN siRNA markedly inhibited the TNFα-induced increase in PTEN (p < 0.01) without significantly changing the p-Akt levels. The vanadium complex, exhibiting insulin-like effects, also significantly prevented the TNFα-induced increase in PTEN. Combining insulin and VO-OHpic was additive, providing both proof of concept and insight into mechanism. Discussion: The PTEN increase due to TNFα treatment was reversible by both PTEN siRNA knockdown and VO-OHpic treatment. Thus, PTEN is identified as a potential new therapeutic target for reducing IR in Type 2 DM. - Highlights: • TNFα treatment induced a significant increase in PTEN in H-411E liver cells. • PTEN siRNA knockdown prevented this effect. • VO-OHpic (vanadium complex) treatment, like insulin, decreased PTEN protein levels. • Thus, PTEN is identified as a potential therapeutic target in DM Type 2.

  4. Preclinical Remodeling of Human Prostate Cancer through the PTEN/AKT Pathway

    Directory of Open Access Journals (Sweden)

    Marco A. De Velasco

    2012-01-01

    Full Text Available Knowledge gained from the identification of genetic and epigenetic alterations that contribute to the progression of prostate cancer in humans is now being implemented in the development of functionally relevant translational models. GEM (genetically modified mouse models are being developed to incorporate the same molecular defects associated with human prostate cancer. Haploinsufficiency is common in prostate cancer and homozygous loss of PTEN is strongly correlated with advanced disease. In this paper, we discuss the evolution of the PTEN knockout mouse and the cooperation between PTEN and other genetic alterations in tumor development and progression. Additionally, we will outline key points that make these models key players in the development of personalized medicine, as potential tools for target and biomarker development and validation as well as models for drug discovery.

  5. Inhibition of transfected PTEN on human colon cancer

    Institute of Scientific and Technical Information of China (English)

    Shou-Shui Xu; Wen-Lu Shen; Song-Ying Ouyang

    2004-01-01

    AIM: To study the inhibitory effect of transfected PTEN on LoVo cells.METHODS: Human PTEN cDNA was transferred into LoVo cells via lipofectin and PTEN mRNA levels and its expression were analyzed by Western blot and flow cytometry. Before or after transfection, the effects of 5-Fu on inhibiting cell proliferation and inducing apoptosis were measured by flow cytometry, DNA bands and MTT.RESULTS: PTEN transfection significantly up-regulated PTEN expression in LoVo cells. 5-Fu inhibited cell proliferation and induced apoptosis in transfected LoVo cells.CONCLUSION: Transfected PTEN can remark ably up-regulate PTEN expression in LoVo cells and promote the apoptosis.PTEN transfection is associated with 5-Fu treatment effect and has a cooperatively cytotoxic effect.

  6. Nuclear PTEN controls DNA repair and sensitivity to genotoxic stress

    Science.gov (United States)

    Bassi, C; Ho, J; Srikumar, T; Dowling, RJO; Gorrini, C; Miller, SJ; Mak, TW; Neel, BG; Raught, B; Stambolic, V

    2016-01-01

    Loss of function of the Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) tumor suppressor gene is associated with many human cancers. In the cytoplasm, PTEN antagonizes the Phosphatidylinositol 3′ kinase (PI3K) signaling pathway. PTEN also accumulates in the nucleus, where its function remains poorly understood. We demonstrate that SUMOylation (SUMO) of PTEN controls its nuclear localization. In cells exposed to genotoxic stress, SUMO-PTEN was rapidly excluded from the nucleus dependent on the protein kinase Ataxia telangiectasia mutated (ATM). Cells lacking nuclear PTEN were hypersensitive to DNA damage, while PTEN-deficient cells were susceptible to killing by a combination of genotoxic stress and a small molecule PI3K inhibitor both in vitro and in vivo. Our findings may have implications for individualized therapy for patients with PTEN-deficient tumors. PMID:23888040

  7. PTEN function: the long and the short of it.

    Science.gov (United States)

    Hopkins, Benjamin D; Hodakoski, Cindy; Barrows, Douglas; Mense, Sarah M; Parsons, Ramon E

    2014-04-01

    Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a phosphatase that is frequently altered in cancer. PTEN has phosphatase-dependent and -independent roles, and genetic alterations in PTEN lead to deregulation of protein synthesis, the cell cycle, migration, growth, DNA repair, and survival signaling. PTEN localization, stability, conformation, and phosphatase activity are controlled by an array of protein-protein interactions and post-translational modifications. Thus, PTEN-interacting and -modifying proteins have profound effects on the tumor suppressive functions of PTEN. Moreover, recent studies identified mechanisms by which PTEN can exit cells, via either exosomal export or secretion, and act on neighboring cells. This review focuses on modes of PTEN protein regulation and ways in which perturbations in this regulation may lead to disease.

  8. Growth and activation of PI-3K/PKB and Akt by stromal cell-derived factor 1α in endometrial carcinoma cells with expression of suppressor endoprotein PTEN

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-ping; ZHAO Dan; GAO Min; ZHAO Chao; WANG Jian-liu; WEI Li-hui

    2006-01-01

    Background Mutation or deletion in the phosphatase and tensin homologue deleted on chromosome ten (PTEN)gene has been identified as an important cause of endometrial carcinoma; stromal cell derived factor-1α (SDF-1α)exerts growth-promoting effects on endometrial cancer cells through activation of the PI-3 kinase/Akt pathway and downstream effectors such as extracellular-responsive kinase (ERK). In this study, a plasmid containing the PTEN gene was transfected into Ishikawa cells to investigate the difference in growth and signal transduction between Ishikawa-PTEN and Ishikawa cells after SDF-1α stimulation, and to study mechanisms of the involvement of PTEN protein in endometrial carcinoma development.Methods Ishikawa cells were transfected with a plasmid (pLXSN-PTEN) containing the PTEN gene and a plasmid (pLXSN-EGFP) with enhanced green fluorescent protein (EGFP). Cells were then screened to obtain Ishikawa-PTEN cells and Ishikawa-neo cells that can both stably express PTEN protein and EGFP. Expression of PTEN protein, phosphorylation levels of AKT and ERK (pAKT and pERK) and growth differences in Ishikawa-PTEN, Ishikawa-neo and Ishikawa cells before and after SDF-1α stimulation were then determined by Western blots and MTT assays.Results Western blot analysis showed that Ishikawa cells produced PTEN after transfection with the PTEN gene. At 15 minutes after SDF-1α stimulation, the pAKT level of Ishikawa-PTEN cells was lower than that of Ishikawa-neo cells and Ishikawa cells. There was no significant difference in pERK levels among the three cell lines. The positive effect of SDF-1α on Ishikawa-PTEN cells growth was markedly less than the effect on Ishikawa-neo and Ishikawa cells. However, in the absence of SDF-1α stimulation (baseline), the pAKT level in Ishikawa-PTEN cells was less than that in Ishikawa cells. There was a significant difference in growth between the Ishikawa-PTEN cells and the Ishikawa-neo cells.Conclusions PTEN gene transfection can

  9. [Mammary ductal ectasia child. Diagnostic and therapeutic approach].

    Science.gov (United States)

    Martínez-Medel, Jorge; Cabistany-Esqué, Ana Cristina; Sanz-Asin, Olga; del Martínez-Rubio, María Pilar; Echavarren-Plaza, Virginia; Arroyo-Lemarroy, Taydé

    2014-01-01

    Mammary duct ectasia in childhood is a rare disease. It appears typically as a periareolar mammary mass and/or nipple discharge. Even though in the adult age is an acquired disease, its occurrence in children suggests it may constitute a development mammary gland anomaly. Sonography is highly useful in the diagnosis. Differential diagnosis must include other nipple discharge and mammary mass causes as the juvenile fibroadenoma or malignant pathology. This usually is a self-limited process, so that a conservative approach is recommended, even though occasionally surgical treatment is required. We report the case of a 13 years old girl with nipple discharge who finally was diagnosed bilateral mammary duct ectasia.

  10. PTEN coding product:a new marker for tumorigenesis and progession of endometrial carcinoma

    Institute of Scientific and Technical Information of China (English)

    Gao Qinglei; Li Jing; Xing Hui; Lu Yunping; Zhou Jianfeng; Ma Ding

    2008-01-01

    Objective :To investigate the expression of PTEN in carcinogenesis and development of endometrial carcinoma.Methods: The expression of PTEN was detected by reverse transcription-polymerase chain reaction(RT-PCR) methods from 24 cases with endometrial carcinoma,10 cases with endometrial atypical hyperplasia,I0 eases with endometrial hyperplasia and I0 cases with normal endometrium and by SP immunohistochemical methods from 73 cases with endometrial carcinoma,25 cases with endometrial atypical hyperplasia,71 cases with endometrial hyperplasia and 31 cases with normal endometrium.Results:PTEN expression of both RNA and protein in patients with endometrial carcinoma and endometrial atypical hyperplasia was significantly lower than that of patients with endometrial hyperplasia and normal endometriurn.mRNA relative value was 0.35±0.13,0.46±0.11,2.32±0.32,2.45±0.51,respectively.Loss of PTEN expression rates were 66.67% (38/57) ,76.00% ( 19/25 ) ,5.63% (4/71 ) ,0 (0/31 ),repeetively.The results were also compared with clinical parameters.Loss of PTEN expression in patients with endometrial carcinoma was significantly related to histological classification ( P < 0.0001 ) and differentiation ( P < 0.05 ).It was not related to depth of myometrium invasion and clinical stage( P >0.05 ).Conclusion:Loss of PTEN expression is an early event in endometrial tumorigenesis.Detection of PTEN protein may be a diagnostic biomarker for endometrial precancers and adenocareinoma.

  11. PTEN and p16 genes as epigenetic biomarkers in oral squamous cell carcinoma (OSCC): a study on south Indian population.

    Science.gov (United States)

    Sushma, P S; Jamil, Kaiser; Kumar, P Uday; Satyanarayana, U; Ramakrishna, M; Triveni, B

    2016-06-01

    Phosphatase and tensin homolog (PTEN) and p16INK4a (p16) genes are tumor suppressor genes, associated with epigenetic alterations. PTEN and p16 promoter hypermethylation is a major epigenetic silencing mechanism leading to cancer. The cooperation between PTEN and p16 in pathogenesis of cancers suggest that their combination might be considered as potential molecular marker for specific subgroups of patients. Hence, the present study aimed to investigate whether PTEN and p16 promoter methylations were involved in oral squamous cell carcinoma (OSCC) in south Indian subjects. DNA methylation quantitative analyses of the two candidate tumor suppressor genes PTEN and p16 were performed by methylation-specific polymerase chain reaction (MSP). Fifty OSCC biopsy samples and their corresponding non-malignant portions as controls were studied comparatively. The methylation status was correlated with the clinical manifestations. Twelve out of 50 patients (24 %) were found to be methylated for PTEN gene, whereas methylation of the p16 gene occurred in 19 out of 50 cases (38 %). A statistically significant result was obtained (P = p16 genes. PTEN and p16 promoter methylation may be the main mechanism leading to the low expression of PTEN and p16 genes indicating the progress of tumor development. Our data suggest that a low PTEN and p16 expression due to methylation may contribute to the cancer progression and could be useful for prognosis of OSCC. Therefore, analysis of promoter methylation in such genes may provide a biomarker valuable for early detection of oral cancer.

  12. Honey bee PTEN--description, developmental knockdown, and tissue-specific expression of splice-variants correlated with alternative social phenotypes.

    Directory of Open Access Journals (Sweden)

    Navdeep S Mutti

    Full Text Available BACKGROUND: Phosphatase and TENsin (PTEN homolog is a negative regulator that takes part in IIS (insulin/insulin-like signaling and Egfr (epidermal growth factor receptor activation in Drosophila melanogaster. IIS and Egfr signaling events are also involved in the developmental process of queen and worker differentiation in honey bees (Apis mellifera. Here, we characterized the bee PTEN gene homologue for the first time and begin to explore its potential function during bee development and adult life. RESULTS: Honey bee PTEN is alternatively spliced, resulting in three splice variants. Next, we show that the expression of PTEN can be down-regulated by RNA interference (RNAi in the larval stage, when female caste fate is determined. Relative to controls, we observed that RNAi efficacy is dependent on the amount of PTEN dsRNA that is delivered to larvae. For larvae fed queen or worker diets containing a high amount of PTEN dsRNA, PTEN knockdown was significant at a whole-body level but lethal. A lower dosage did not result in a significant gene down-regulation. Finally, we compared same-aged adult workers with different behavior: nursing vs. foraging. We show that between nurses and foragers, PTEN isoforms were differentially expressed within brain, ovary and fat body tissues. All isoforms were expressed at higher levels in the brain and ovaries of the foragers. In fat body, isoform B was expressed at higher level in the nurse bees. CONCLUSION: Our results suggest that PTEN plays a central role during growth and development in queen- and worker-destined honey bees. In adult workers, moreover, tissue-specific patterns of PTEN isoform expression are correlated with differences in complex division of labor between same-aged individuals. Therefore, we propose that knowledge on the roles of IIS and Egfr activity in developmental and behavioral control may increase through studies of how PTEN functions can impact bee social phenotypes.

  13. Development of Hyperplasias, Preneoplasias, and Mammary Tumors in MMTV-c-erbB-2 and MMTV-TGFα Transgenic Rats

    OpenAIRE

    Davies, Barry R.; Platt-Higgins, Angela M.; Schmidt, Gunter; Rudland, Philip S.

    1999-01-01

    Human cDNAs corresponding to two epidermal growth factor-related products that are overexpressed in human breast cancers, that for c-erbB-2 (HER-2) and for transforming growth factor α (TGFα), have been cloned downstream of the mouse mammary tumor virus (MMTV) long terminal repeat promoter and injected into the pronucleus of fertilized oocytes of Sprague-Dawley rats to produce transgenic offspring. Expression of the transgenic mRNAs is not detectable in mammary tissue from virgin transgenic r...

  14. Can we accurately report PTEN status in advanced colorectal cancer?

    OpenAIRE

    Hocking, Christopher; Hardingham, Jennifer E.; Broadbridge, Vy; Wrin, Joe; Townsend, Amanda R; Tebbutt, Niall; Cooper, John; Ruszkiewicz, Andrew; Lee, Chee; Price, Timothy J.

    2014-01-01

    Background Loss of phosphatase and tensin homologue (PTEN) function evaluated by loss of PTEN protein expression on immunohistochemistry (IHC) has been reported as both prognostic in metastatic colorectal cancer and predictive of response to anti-EGFR monoclonal antibodies although results remain uncertain. Difficulties in the methodological assessment of PTEN are likely to be a major contributor to recent conflicting results. Methods We assessed loss of PTEN function in 51 colorectal cancer ...

  15. EXPRESSION AND SIGNIFICANCE OF PTEN IN ENDOMETRIAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    GE Xiu-jun; LIU Zhi-hui; LI Ying-yong; Gao Rui-ping

    2005-01-01

    Objective: To investigate the expression of PTEN in endometrial carcinoma and its clinical significance. Methods: Reverse transcriptase-polymerase chain reaction and Western-blot methods were used to detect PTEN expression in 28 cases of endometrial carcinoma. Results: mRNA and protein expression levels of PTEN in endometrial carcinomas were significantly lower than those in normal endometrium (P<0.01). Conclusion: PTEN may play an important role in the tumorigenesis of endometrial carcinoma.

  16. PTEN regulates colorectal epithelial apoptosis through Cdc42 signalling

    OpenAIRE

    Deevi, R; A. Fatehullah; Jagan, I; Nagaraju, M; Bingham, V; Campbell, F C

    2011-01-01

    Background: Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) regulation of the Rho-like GTPase Cdc42 has a central role in epithelial polarised growth, but effects of this molecular network on apoptosis remain unclear. Methods: To investigate the role of Cdc42 in PTEN-dependent cell death, we used flow cytometry, in vitro pull-down assays, poly(ADP ribose) polymerase (PARP) cleavage and other immunoblots in isogenic PTEN-expressing and -deficient colorectal cells (HCT116PTEN+/...

  17. MicroRNAs in the development and neoplasia of the mammary gland [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Jena

    2017-06-01

    Full Text Available Study on the role of microRNAs (miRs as regulators of gene expression through posttranscriptional gene silencing is currently gaining much interest,due to their wide involvement in different physiological processes. Understanding mammary gland development, lactation, and neoplasia in relation to miRs is essential. miR expression profiling of the mammary gland from different species in various developmental stages shows their role as critical regulators of development. miRs such as miR-126, miR-150, and miR-145 have been shown to be involved in lipid metabolism during lactation. In addition, lactogenic hormones influence miR expression as evidenced by overexpression of miR-148a in cow mammary epithelial cells, leading to enhanced lactation. Similarly, the miR-29 family modulates lactation-related gene expression by regulating DNA methylation of their promoters. Besides their role in development, lactation and involution, miRs are responsible for breast cancer development. Perturbed estrogen (E2 signaling is one of the major causes of breast cancer. Increased E2 levels cause altered expression of ERα, and ERα-miR cross-talk promotes tumour progression. miRs, such as miR-206, miR-34a, miR-17-5p, and miR-125 a/b are found to be tumour suppressors; whereas miR-21, miR-10B, and miR-155 are oncogenes.Studies using an ACI rat model showed similar findings of miR dysregulation due to excess E2, and a natural phenol antioxidant ellagic acid showed therapeutic properties by reversing the miR dysregulation. This review focuses on the recent findings concerning the role of miRs in developmental stages of the mammary gland (mainly lactation and involution stages and their involvement in breast cancer progression. Further studies in this area will help us understand the molecular details of mammary gland biology,as well as miRs that could be therapeutic targets of breast cancer.

  18. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review.

    Science.gov (United States)

    Lohakare, J D; Südekum, K-H; Pattanaik, A K

    2012-09-01

    This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only reduces the age of sexual maturity but also lowers the time period of attaining the age of first calving. However, high energy diets may cause undesirable fat deposition thereby affecting future milk yield potential. Discrepancies exist whether overfed or overweight heifers at puberty can influence the mammary development and future milk yield potential and performance. The data on post-pubertal nutritional management suggested that body weight at calving and post-pubertal growth rate is important in first lactation milk yield. There is a continuous research need for strategic feeding that accelerates growth of dairy heifers without reduction in subsequent production. Nutritional management from birth, across puberty and during pregnancy is critical for mammary growth and for producing a successful cow. This review will mostly highlight studies carried out on dairy breeds and possible available opportunities to manipulate nutritional status from birth until age at first calving.

  19. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review

    Directory of Open Access Journals (Sweden)

    J. D. Lohakare

    2012-09-01

    Full Text Available This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only reduces the age of sexual maturity but also lowers the time period of attaining the age of first calving. However, high energy diets may cause undesirable fat deposition thereby affecting future milk yield potential. Discrepancies exist whether overfed or overweight heifers at puberty can influence the mammary development and future milk yield potential and performance. The data on post-pubertal nutritional management suggested that body weight at calving and post-pubertal growth rate is important in first lactation milk yield. There is a continuous research need for strategic feeding that accelerates growth of dairy heifers without reduction in subsequent production. Nutritional management from birth, across puberty and during pregnancy is critical for mammary growth and for producing a successful cow. This review will mostly highlight studies carried out on dairy breeds and possible available opportunities to manipulate nutritional status from birth until age at first calving.

  20. Quantitative Analysis of the Human Milk Whey Proteome Reveals Developing Milk and Mammary-Gland Functions across the First Year of Lactation

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2013-09-01

    Full Text Available In-depth understanding of the changing functions of human milk (HM proteins and the corresponding physiological adaptions of the lactating mammary gland has been inhibited by incomplete knowledge of the HM proteome. We analyzed the HM whey proteome (n = 10 women with samples at 1 week and 1, 3, 6, 9 and 12 months using a quantitative proteomic approach. One thousand three hundred and thirty three proteins were identified with 615 being quantified. Principal component analysis revealed a transition in the HM whey proteome-throughout the first year of lactation. Abundance changes in IgG, sIgA and sIgM display distinct features during the first year. Complement components and other acute-phase proteins are generally at higher levels in early lactation. Proteomic analysis further suggests that the sources of milk fatty acids (FA shift from more direct blood influx to more de novo mammary synthesis over lactation. The abundances of the majority of glycoproteins decline over lactation, which is consistent with increased enzyme expression in glycoprotein degradation and decreased enzyme expression in glycoprotein synthesis. Cellular detoxification machinery may be transformed as well, thereby accommodating increased metabolic activities in late lactation. The multiple developing functions of HM proteins and the corresponding mammary adaption become more apparent from this study.

  1. Quantitative Analysis of the Human Milk Whey Proteome Reveals Developing Milk and Mammary-Gland Functions across the First Year of Lactation.

    Science.gov (United States)

    Zhang, Qiang; Cundiff, Judy K; Maria, Sarah D; McMahon, Robert J; Woo, Jessica G; Davidson, Barbara S; Morrow, Ardythe L

    2013-09-03

    In-depth understanding of the changing functions of human milk (HM) proteins and the corresponding physiological adaptions of the lactating mammary gland has been inhibited by incomplete knowledge of the HM proteome. We analyzed the HM whey proteome (n = 10 women with samples at 1 week and 1, 3, 6, 9 and 12 months) using a quantitative proteomic approach. One thousand three hundred and thirty three proteins were identified with 615 being quantified. Principal component analysis revealed a transition in the HM whey proteome-throughout the first year of lactation. Abundance changes in IgG, sIgA and sIgM display distinct features during the first year. Complement components and other acute-phase proteins are generally at higher levels in early lactation. Proteomic analysis further suggests that the sources of milk fatty acids (FA) shift from more direct blood influx to more de novo mammary synthesis over lactation. The abundances of the majority of glycoproteins decline over lactation, which is consistent with increased enzyme expression in glycoprotein degradation and decreased enzyme expression in glycoprotein synthesis. Cellular detoxification machinery may be transformed as well, thereby accommodating increased metabolic activities in late lactation. The multiple developing functions of HM proteins and the corresponding mammary adaption become more apparent from this study.

  2. PTEN mosaicism with features of Cowden syndrome.

    Science.gov (United States)

    Gammon, A; Jasperson, K; Pilarski, R; Prior, Tw; Kuwada, S

    2013-12-01

    We present the first known case of somatic PTEN mosaicism causing features of Cowden syndrome (CS) and inheritance in the subsequent generation. A 20-year-old woman presented for genetics evaluation with multiple ganglioneuromas of the colon. On examination, she was found to have a thyroid goiter, macrocephaly, and tongue papules, all suggestive of CS. However, her reported family history was not suspicious for CS. A deleterious PTEN mutation was identified in blood lymphocytes, 966A>G, 967delA. Genetic testing was recommended for her parents. Her 48-year-old father was referred for evaluation and was found to have macrocephaly and a history of Hashimoto's thyroiditis, but no other features of CS. Site-specific genetic testing carried out on blood lymphocytes showed mosaicism for the same PTEN mutation identified in his daughter. Identifying PTEN mosaicism in the proband's father had significant implications for the risk assessment/genetic testing plan for the rest of his family. His result also provides impetus for somatic mosaicism in a parent to be considered when a de novo PTEN mutation is suspected.

  3. A Tale of Two Signals: AR and WNT in Development and Tumorigenesis of Prostate and Mammary Gland

    Directory of Open Access Journals (Sweden)

    Hubert Pakula

    2017-01-01

    Full Text Available Prostate cancer (PCa is one of the most common cancers and among the leading causes of cancer deaths for men in industrialized countries. It has long been recognized that the prostate is an androgen-dependent organ and PCa is an androgen-dependent disease. Androgen action is mediated by the androgen receptor (AR. Androgen deprivation therapy (ADT is the standard treatment for metastatic PCa. However, almost all advanced PCa cases progress to castration-resistant prostate cancer (CRPC after a period of ADT. A variety of mechanisms of progression from androgen-dependent PCa to CRPC under ADT have been postulated, but it remains largely unclear as to when and how castration resistance arises within prostate tumors. In addition, AR signaling may be modulated by extracellular factors among which are the cysteine-rich glycoproteins WNTs. The WNTs are capable of signaling through several pathways, the best-characterized being the canonical WNT/β-catenin/TCF-mediated canonical pathway. Recent studies from sequencing PCa genomes revealed that CRPC cells frequently harbor mutations in major components of the WNT/β-catenin pathway. Moreover, the finding of an interaction between β-catenin and AR suggests a possible mechanism of cross talk between WNT and androgen/AR signaling pathways. In this review, we discuss the current knowledge of both AR and WNT pathways in prostate development and tumorigenesis, and their interaction during development of CRPC. We also review the possible therapeutic application of drugs that target both AR and WNT/β-catenin pathways. Finally, we extend our review of AR and WNT signaling to the mammary gland system and breast cancer. We highlight that the role of AR signaling and its interaction with WNT signaling in these two hormone-related cancer types are highly context-dependent.

  4. Von Hippel-Lindau status influences phenotype of liver cancers arising from PTEN loss

    Directory of Open Access Journals (Sweden)

    Sendor AB

    2015-02-01

    Full Text Available Adam B Sendor,1 Kathryn E Hacker,1 Shufen Chen,1 Armando L Corona,1 Oishee Sen,1 Derek Y Chiang,1 Anna Snavely,1 Arlin B Rogers,2 Stephanie A Montgomery,1 W Kimryn Rathmell,1 Autumn J McRee11Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA; 2Section of Pathology, Department of Biomedical Sciences, Cummings School of Veterinary Medicine, Tufts University, Boston, MA, USABackground: PTEN loss contributes to the development of liver diseases including hepatic steatosis and both hepatocellular carcinoma (HCC and cholangiocarcinoma (CC. The factors that influence the penetrance of these conditions are unclear. We explored the influence of sustained hypoxia signaling through co-deletion of Pten and Vhl in a murine model.Methods: We used a CreER-linked Keratin 18 mouse model to conditionally delete Pten, Vhl or both in somatic cells of adult mice, evaluating the resultant tumors by histology and gene expression microarray. Existing sets of gene expression data for human HCC and CC were examined for pathways related to those observed in the murine tumors, and a cohort of human CC samples was evaluated for relationships between HIF-1α expression and clinical outcomes.Results: Both Pten deletion genotypes developed liver tumors, but with differing phenotypes. Pten deletion alone led to large hepatic tumors with widespread hepatosteatosis. Co-deletion of Pten and Vhl with the Keratin 18 promoter resulted in reduced steatosis and a reduced tumor burden that was characterized by a trabecular architecture similar to CC. Genes associated with hepatic steatosis were coordinately expressed in the human HCC dataset, while genes involved in hypoxia response were upregulated in tumors from the human CC dataset. HIF-1α expression and overall survival were examined in an independent cohort of human CC tumors with no statistical differences uncovered.Conclusion: Pten deletion in Keratin 18 expressing cells leads to

  5. Mammary Cancer and Activation of Transposable Elements

    Science.gov (United States)

    2015-03-01

    transcriptionally activated during pregnancy and lactation , and the mice are predisposed to develop mammary cancer after a minimum of 3 pregnancies and...pregnancy and lactation . After 3 pregnancies and lactations , but not after 1 pregnancy and lactation , females develop mammary cancers at an average...mated females per experimental condition (1 or 3 pregnancies/ lactations . 5 breeding strategy to develop triple transgenic cancer -prone and control

  6. A functional dissection of PTEN N-terminus : Implications in PTEN subcellular targeting and tumor suppressor activity

    NARCIS (Netherlands)

    Gil, Anabel; Rodríguez-Escudero, Isabel; Stumpf, Miriam; Molina, María; Cid, Víctor J.; Pulido, Rafael

    2015-01-01

    Spatial regulation of the tumor suppressor PTEN is exerted through alternative plasma membrane, cytoplasmic, and nuclear subcellular locations. The N-terminal region of PTEN is important for the control of PTEN subcellular localization and function. It contains both an active nuclear localization

  7. miR-17 inhibitor suppressed osteosarcoma tumor growth and metastasis via increasing PTEN expression

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yong, E-mail: gaoyongunion@163.com [Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Luo, Ling-hui [Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Li, Shuai; Yang, Cao [Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China)

    2014-02-07

    Highlights: • miR-17 was increased in OS tissues and cell lines. • Inhibition of miR-17 suppressed OS cell proliferation. • Inhibition of miR-17 suppressed OS cell migration and invasion. • PTEN was a target of miR-17. • miR-17 was negatively correlated with PTEN in OS tissues. - Abstract: MicroRNAs (miRNAs) play essential roles in cancer development and progression. Here, we investigated the role of miR-17 in the progression and metastasis of osteosarcoma (OS). miR-17 was frequently increased in OS tissues and cell lines. Inhibition of miR-17 in OS cell lines substantially suppressed cell proliferation, migration, and invasion. Phosphatase and tensin homolog (PTEN) was identified as a target of miR-17, and ectopic expression of miR-17 inhibited PTEN by direct binding to its 3′-untranslated region (3′-UTR). Expression of miR-17 was negatively correlated with PTEN in OS tissues. Together, these findings indicate that miR-17 acts as an oncogenic miRNA and may contribute to the progression and metastasis of OS, suggesting miR-17 as a potential novel diagnostic and therapeutic target of OS.

  8. Conditional Inactivation of Pten with EGFR Overexpression in Schwann Cells Models Sporadic MPNST

    Directory of Open Access Journals (Sweden)

    Vincent W. Keng

    2012-01-01

    Full Text Available The genetic mechanisms involved in the transformation from a benign neurofibroma to a malignant sarcoma in patients with neurofibromatosis-type-1- (NF1-associated or sporadic malignant peripheral nerve sheath tumors (MPNSTs remain unclear. It is hypothesized that many genetic changes are involved in transformation. Recently, it has been shown that both phosphatase and tensin homolog (PTEN and epidermal growth factor receptor (EGFR play important roles in the initiation of peripheral nerve sheath tumors (PNSTs. In human MPNSTs, PTEN expression is often reduced, while EGFR expression is often induced. We tested if these two genes cooperate in the evolution of PNSTs. Transgenic mice were generated carrying conditional floxed alleles of Pten, and EGFR was expressed under the control of the 2′,3′-cyclic nucleotide 3′phosphodiesterase (Cnp promoter and a desert hedgehog (Dhh regulatory element driving Cre recombinase transgenic mice (Dhh-Cre. Complete loss of Pten and EGFR overexpression in Schwann cells led to the development of high-grade PNSTs. In vitro experiments using immortalized human Schwann cells demonstrated that loss of PTEN and overexpression of EGFR cooperate to increase cellular proliferation and anchorage-independent colony formation. This mouse model can rapidly recapitulate PNST onset and progression to high-grade PNSTs, as seen in sporadic MPNST patients.

  9. Estimation of mammary gland composition using CdTe series detector developed for photon-counting mammography

    Science.gov (United States)

    Ihori, Akiko; Okamoto, Chizuru; Yamakawa, Tsutomu; Yamamoto, Shuichiro; Okada, Masahiro; Nakajima, Ai; Kato, Misa; Kodera, Yoshie

    2016-03-01

    Energy resolved photon-counting mammography is a new technology, which counts the number of photons that passes through an object, and presents it as a pixel value in an image of the object. Silicon semiconductor detectors are currently used in commercial mammography. However, the disadvantage of silicon is the low absorption efficiency for high X-ray energies. A cadmium telluride (CdTe) series detector has a high absorption efficiency over a wide energy range. In this study, we proposed a method to estimate the composition of the mammary gland using a CdTe series detector as a photon-counting detector. The fact that the detection rate of breast cancer in mammography is affected by mammary gland composition is now widely accepted. Assessment of composition of the mammary gland has important implications. An important advantage of our proposed technique is its ability to discriminate photons using three energy bins. We designed the CdTe series detector system using the MATLAB simulation software. The phantom contains nine regions with the ratio of glandular tissue and adipose varying in increments of 10%. The attenuation coefficient for each bin's energy was calculated from the number of input and output photons possessed by each. The evaluation results obtained by plotting the attenuation coefficient μ in a three-dimensional (3D) scatter plot show that the plots had a regular composition order congruent with that of the mammary gland. Consequently, we believe that our proposed method can be used to estimate the composition of the mammary gland.

  10. PTEN function, the long and the short of it

    Science.gov (United States)

    Hopkins, Benjamin D.; Hodakoski, Cindy; Barrows, Doug; Mense, Sarah; Parsons, Ramon E.

    2014-01-01

    Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is a phosphatase that is frequently altered in cancer. PTEN has phosphatase-dependent and - independent roles; and genetic alterations in PTEN lead to deregulation of protein synthesis, cell cycle, migration, growth, DNA repair, and survival signaling. PTEN localization, stability, conformation, and phosphatase activity are controlled by an array of protein-protein interactions and post-translational modifications. Thus, PTEN-interacting and modifying proteins have profound effects on PTEN’s tumor suppressive functions. Moreover, recent studies identified mechanisms by which PTEN can exit cells, either via exosomal export or secretion, and act on neighboring cells. This review focuses on modes of PTEN protein regulation and ways in which perturbations in this regulation may lead to disease. PMID:24656806

  11. A novel PTEN gene promoter mutation and untypical Cowden syndrome

    Institute of Scientific and Technical Information of China (English)

    Chen Liu; Guangbing Li; Rongrong Chen; Xiaobo Yang; Xue Zhao; Haitao Zhao

    2013-01-01

    Cowden syndrome (CS),an autosomal dominant disorder,is one of a spectrum of clinical disorders that have been linked to germline mutations in the phosphatase and tensin homolog (PTEN) gene.Although 70-80% of patients with CS have an identifiable germline PTEN mutation,the clinical diagnosis presents many challenges because of the phenotypic and genotypic variations.In the present study,we sequenced the exons and the promoter of PTEN gene,mutations and variations in the promoter and exons were identified,and a PTEN protein expression negative region was determined by immunohistochemistry (IHC).In conclusion,a novel promoter mutation we found in PTEN gene may turn off PTEN protein expression occasionally,leading to the disorder of PTEN and untypical CS manifestations.

  12. Luteolin suppresses development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats.

    Science.gov (United States)

    Cook, Matthew T; Mafuvadze, Benford; Besch-Williford, Cynthia; Ellersieck, Mark R; Goyette, Sandy; Hyder, Salman M

    2016-02-01

    Postmenopausal women undergoing hormone-replacement therapy containing both progestins and estrogens are at an increased risk of developing breast cancer compared with women taking estrogen alone. We recently demonstrated that medroxyprogesterone acetate, a progestin commonly used for hormone-replacement therapy, accelerates development of mammary carcinogenesis in 7,12-dimethylbenz(a)anthracene‑treated Sprague-Dawley rats. Synthetic antiprogestins used to block the deleterious effects of progestins, are themselves associated with toxic side-effects. In order to circumvent this, we used the aforementioned model to identify less toxic natural compounds that may prevent the development of progestin-accelerated tumors. Luteolin, a naturally-occurring flavonoid commonly found in fruits and vegetables, has previously been shown to possess anticancer properties. In our studies, both low (1 mg/kg) and high (25 mg/kg) doses of luteolin significantly suppressed progestin-dependent increases in tumor incidence, while increasing tumor latency and reducing the occurrence of large (>300 mm3) mammary tumors. However, an intermediate dose of luteolin (10 mg/kg), while suppressing the development of large tumors, did not affect either tumor incidence or latency. Immunohistochemical analysis of tumor tissues revealed that all concentrations of luteolin (1, 10, and 25 mg/kg) significantly reduced levels of VEGF within tumors. The suppressive effects of luteolin on tumor incidence and volume, together with its ability to reduce VEGF and blood vessels, persisted even after treatment was terminated. This suggests that luteolin possesses anti‑angiogenic properties which could mechanistically explain its capacity to control tumor progression. Thus luteolin may be a valuable, non-toxic, naturally-occurring anticancer compound which may potentially be used to combat progestin-accelerated mammary tumors.

  13. The tumor suppressor PTEN and the PDK1 kinase regulate formation of the columnar neural epithelium.

    Science.gov (United States)

    Grego-Bessa, Joaquim; Bloomekatz, Joshua; Castel, Pau; Omelchenko, Tatiana; Baselga, José; Anderson, Kathryn V

    2016-01-26

    Epithelial morphogenesis and stability are essential for normal development and organ homeostasis. The mouse neural plate is a cuboidal epithelium that remodels into a columnar pseudostratified epithelium over the course of 24 hr. Here we show that the transition to a columnar epithelium fails in mutant embryos that lack the tumor suppressor PTEN, although proliferation, patterning and apical-basal polarity markers are normal in the mutants. The Pten phenotype is mimicked by constitutive activation of PI3 kinase and is rescued by the removal of PDK1 (PDPK1), but does not depend on the downstream kinases AKT and mTORC1. High resolution imaging shows that PTEN is required for stabilization of planar cell packing in the neural plate and for the formation of stable apical-basal microtubule arrays. The data suggest that appropriate levels of membrane-associated PDPK1 are required for stabilization of apical junctions, which promotes cell elongation, during epithelial morphogenesis.

  14. Characterization of Heterogeneous Prostate Tumors in Targeted Pten Knockout Mice.

    Directory of Open Access Journals (Sweden)

    Hanneke Korsten

    Full Text Available Previously, we generated a preclinical mouse prostate tumor model based on PSA-Cre driven inactivation of Pten. In this model homogeneous hyperplastic prostates (4-5m developed at older age (>10m into tumors. Here, we describe the molecular and histological characterization of the tumors in order to better understand the processes that are associated with prostate tumorigenesis in this targeted mouse Pten knockout model. The morphologies of the tumors that developed were very heterogeneous. Different histopathological growth patterns could be identified, including intraductal carcinoma (IDC, adenocarcinoma and undifferentiated carcinoma, all strongly positive for the epithelial cell marker Cytokeratin (CK, and carcinosarcomas, which were negative for CK. IDC pattern was already detected in prostates of 7-8 month old mice, indicating that it could be a precursor stage. At more than 10 months IDC and carcinosarcoma were most frequently observed. Gene expression profiling discriminated essentially two molecular subtypes, denoted tumor class 1 (TC1 and tumor class 2 (TC2. TC1 tumors were characterized by high expression of epithelial markers like Cytokeratin 8 and E-Cadherin whereas TC2 tumors showed high expression of mesenchyme/stroma markers such as Snail and Fibronectin. These molecular subtypes corresponded with histological growth patterns: where TC1 tumors mainly represented adenocarcinoma/intraductal carcinoma, in TC2 tumors carcinosarcoma was the dominant growth pattern. Further molecular characterization of the prostate tumors revealed an increased expression of genes associated with the inflammatory response. Moreover, functional markers for senescence, proliferation, angiogenesis and apoptosis were higher expressed in tumors compared to hyperplasia. The highest expression of proliferation and angiogenesis markers was detected in TC2 tumors. Our data clearly showed that in the genetically well-defined PSA-Cre;Pten-loxP/loxP prostate tumor

  15. In Utero Exposure to Cadmium, Mammary Gland Development, and Breast Cancer Risk

    Science.gov (United States)

    2007-05-01

    fetal development, are re-employed at times of tissue remodeling or wound healing during adulthood. These signal transduction systems effect...Danielsen, E. Pentecost , and A. Stoica. 2002. Role of Cadmium in the Regulation of AR Gene Expression and Activity. Endocrinology. 143:263-275

  16. Gpr177 Deficiency Impairs Mammary Development and Prohibits Wnt-Induced Tumorigenesis

    OpenAIRE

    Eri Ohfuchi Maruyama; H-M Ivy Yu; Ming Jiang; Jiang Fu; Wei Hsu

    2013-01-01

    Aberrant regulation of the Wnt pathway, essential for various developmental processes, is tightly linked to human breast cancers. By hijacking this evolutionary conserved signaling pathway, cancer cells acquire sustaining proliferation ability, leading to modification of physiologic properties necessary for tumor initiation and progression. An enormous wealth of knowledge on the importance of Wnt signaling in breast development and cancer has been obtained, but the cell types responsible for ...

  17. The Parvalbumin/Somatostatin Ratio Is Increased in Pten Mutant Mice and by Human PTEN ASD Alleles

    Directory of Open Access Journals (Sweden)

    Daniel Vogt

    2015-05-01

    Full Text Available Mutations in the phosphatase PTEN are strongly implicated in autism spectrum disorder (ASD. Here, we investigate the function of Pten in cortical GABAergic neurons using conditional mutagenesis in mice. Loss of Pten results in a preferential loss of SST+ interneurons, which increases the ratio of parvalbumin/somatostatin (PV/SST interneurons, ectopic PV+ projections in layer I, and inhibition onto glutamatergic cortical neurons. Pten mutant mice exhibit deficits in social behavior and changes in electroencephalogram (EEG power. Using medial ganglionic eminence (MGE transplantation, we test for cell-autonomous functional differences between human PTEN wild-type (WT and ASD alleles. The PTEN ASD alleles are hypomorphic in regulating cell size and the PV/SST ratio in comparison to WT PTEN. This MGE transplantation/complementation assay is efficient and is generally applicable for functional testing of ASD alleles in vivo.

  18. The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor Development

    Science.gov (United States)

    2015-09-01

    prognosis triple negative (ER-, PR-, and HER2-) invasive carcinomas with high frequencies of metaplastic and medullary differentiation(23-25). To...Clinically, the majority of CL tumors are poor prognosis triple - negative (ER, PR, and HER2) invasive carcinomas with high frequencies of metaplastic and...AWARD NUMBER: W81XWH-13-1-0282 TITLE: The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor

  19. Phosphorylation of PTEN increase in pathological right ventricular hypertrophy in rats with chronic hypoxia induced pulmonary hypertension

    Institute of Scientific and Technical Information of China (English)

    Nie Xin; Shi Yiwei; Yu Wenyan; Xu Jianying; Hu Xiaoyun; Du Yongcheng

    2014-01-01

    Background Phosphatase and tensin homologue on chromosome ten (PTEN) acts as a convergent nodal signalling point for cardiomyocyte hypertrophy,growth and survival.However,the role of PTEN in cardiac conditions such as right ventricular hypertrophy caused by chronic hypoxic pulmonary,hypertension remains unclear.This study preliminarily discussed the role of PTEN in the cardiac response to increased pulmonary vascular resistance using the hypoxia-induced PH rats.Methods Male Sprague Dawley rats were exposed to 10% oxygen for 1,3,7,14 or 21 days to induce hypertension and right ventricular hypertrophy.Right ventricular systolic pressure was measured via catheterization.Hypertrophy index was calculated as the ratio of right ventricular mass to left ventricle plus septum mass.Tissue morphology and fibrosis were measured using hematoxylin,eosin and picrosirius red staining.The expression and phosphorylation levels of PTEN in ventricles were determined by real time PCR and Western blotting.Results Hypoxic exposure of rats resulted in pathological hypertrophy,interstitial fibrosis and remodelling of the right ventricle.The phosphorylation of PTEN increased significantly in the hypertrophic right ventricle compared to the normoxic control group.There were no changes in protein expression in either ventricle.Conclusion Hypoxia induced pulmonary hypertension developed pathological right ventricular hypertrophy and remodelling probablv related to an increased phosohorvlation of PTEN.

  20. PTEN microdeletions in T-cell acute lymphoblastic leukemia are caused by illegitimate RAG-mediated recombination events.

    Science.gov (United States)

    Mendes, Rui D; Sarmento, Leonor M; Canté-Barrett, Kirsten; Zuurbier, Linda; Buijs-Gladdines, Jessica G C A M; Póvoa, Vanda; Smits, Willem K; Abecasis, Miguel; Yunes, J Andres; Sonneveld, Edwin; Horstmann, Martin A; Pieters, Rob; Barata, João T; Meijerink, Jules P P

    2014-07-24

    Phosphatase and tensin homolog (PTEN)-inactivating mutations and/or deletions are an independent risk factor for relapse of T-cell acute lymphoblastic leukemia (T-ALL) patients treated on Dutch Childhood Oncology Group or German Cooperative Study Group for Childhood Acute Lymphoblastic Leukemia protocols. Some monoallelic mutated or PTEN wild-type patients lack PTEN protein, implying that additional PTEN inactivation mechanisms exist. We show that PTEN is inactivated by small deletions affecting a few exons in 8% of pediatric T-ALL patients. These microdeletions were clonal in 3% and subclonal in 5% of patients. Conserved deletion breakpoints are flanked by cryptic recombination signal sequences (cRSSs) and frequently have non-template-derived nucleotides inserted in between breakpoints, pointing to an illegitimate RAG recombination-driven activity. Identified cRSSs drive RAG-dependent recombination in a reporter system as efficiently as bona fide RSSs that flank gene segments of the T-cell receptor locus. Remarkably, equivalent microdeletions were detected in thymocytes of healthy individuals. Microdeletions strongly associate with the TALLMO subtype characterized by TAL1 or LMO2 rearrangements. Primary and secondary xenotransplantation of TAL1-rearranged leukemia allowed development of leukemic subclones with newly acquired PTEN microdeletions. Ongoing RAG activity may therefore actively contribute to the acquisition of preleukemic hits, clonal diversification, and disease progression. © 2014 by The American Society of Hematology.

  1. Mammary Cancer and Activation of Transposable Elements

    Science.gov (United States)

    2012-09-01

    SV40Tag is transcriptionally activated during pregnancy and lactation , and the mice are predisposed to develop mammary cancer after 3 pregnancies...and lactations . Using this model, populations of marked cells can be collected for integrated analysis of gene expression, promoter usage, and DNA...completed over the first 6 months on the job . Training included mouse husbandry and colony management, mammary cell isolations in preparation for

  2. MDH2 Stimulated by Estrogen-GPR30 Pathway Down-Regulated PTEN Expression Promoting the Proliferation and Invasion of Cells in Endometrial Cancer

    Directory of Open Access Journals (Sweden)

    Yan Zhuang

    2017-04-01

    Full Text Available PURPOSE: The relationship between endometrial carcinoma and cellular metabolism is unknown. In endometrial cancer, mutation rate of PTEN has been reported very high. Malate dehydrogenase 2 (MDH2 is one of the isoforms of malate dehydrogenase, which is involved in citric acid cycle in mitochondria. Our study aimed to investigate the role MDH2 played in PTEN-regulated endometrial carcinoma. METHODS: To reveal the expression of MDH2 and the co-localization of PTEN and MDH2, immunohistochemistry and immunofluorescent staining were used. Western blot, Real-time PCR, RNA interference and overexpression plasmid DNA transfection were performed to investigate the relationship between PTEN and MDH2 as well as the impact of E2 on the expression of PTEN and MDH2, while CCK8, transwell and flow cytometric analysis were carried out to evaluate the proliferation, migration and invasion and apoptosis of endometrial carcinoma cell lines. RESULTS: Our results demonstrated that as a metabolism related enzyme, MDH2 was overexpressed in endometrial carcinoma tissues and related to the grade of the cancer (P = .038. Western blot, Real-time PCR and immunofluorescent staining revealed MDH2 inhibited the expression of PTEN and was co-localized with PTEN in the cytoplasm of endometrial carcinoma. Proliferation, transwell and apoptosis assay suggested that MDH2 enhanced the proliferation, migration and invasion but inhibited the apoptosis of endometrial cancer cell line through suppressing PTEN. Furthermore, E2 inhibited the expression level of PTEN but enhanced MDH2 via GPR30. CONCLUSIONS: Our study demonstrated that MDH2, stimulated by estrogen, was involved in the development of PTEN-regulated endometrial carcinoma through GPR30-related pathway.

  3. The mammary cellular hierarchy and breast cancer.

    Science.gov (United States)

    Oakes, Samantha R; Gallego-Ortega, David; Ormandy, Christopher J

    2014-11-01

    Advances in the study of hematopoietic cell maturation have paved the way to a deeper understanding the stem and progenitor cellular hierarchy in the mammary gland. The mammary epithelium, unlike the hematopoietic cellular hierarchy, sits in a complex niche where communication between epithelial cells and signals from the systemic hormonal milieu, as well as from extra-cellular matrix, influence cell fate decisions and contribute to tissue homeostasis. We review the discovery, definition and regulation of the mammary cellular hierarchy and we describe the development of the concepts that have guided our investigations. We outline recent advances in in vivo lineage tracing that is now challenging many of our assumptions regarding the behavior of mammary stem cells, and we show how understanding these cellular lineages has altered our view of breast cancer.

  4. Identification of Putative Ortholog Gene Blocks Involved in Gestant and Lactating Mammary Gland Development: A Rodent Cross-Species Microarray Transcriptomics Approach

    Science.gov (United States)

    Rodríguez-Cruz, Maricela; Coral-Vázquez, Ramón M.; Hernández-Stengele, Gabriel; Sánchez, Raúl; Salazar, Emmanuel; Sanchez-Muñoz, Fausto; Encarnación-Guevara, Sergio; Ramírez-Salcedo, Jorge

    2013-01-01

    The mammary gland (MG) undergoes functional and metabolic changes during the transition from pregnancy to lactation, possibly by regulation of conserved genes. The objective was to elucidate orthologous genes, chromosome clusters and putative conserved transcriptional modules during MG development. We analyzed expression of 22,000 transcripts using murine microarrays and RNA samples of MG from virgin, pregnant, and lactating rats by cross-species hybridization. We identified 521 transcripts differentially expressed; upregulated in early (78%) and midpregnancy (89%) and early lactation (64%), but downregulated in mid-lactation (61%). Putative orthologous genes were identified. We mapped the altered genes to orthologous chromosomal locations in human and mouse. Eighteen sets of conserved genes associated with key cellular functions were revealed and conserved transcription factor binding site search entailed possible coregulation among all eight block sets of genes. This study demonstrates that the use of heterologous array hybridization for screening of orthologous gene expression from rat revealed sets of conserved genes arranged in chromosomal order implicated in signaling pathways and functional ontology. Results demonstrate the utilization power of comparative genomics and prove the feasibility of using rodent microarrays to identification of putative coexpressed orthologous genes involved in the control of human mammary gland development. PMID:24288657

  5. Identification of Putative Ortholog Gene Blocks Involved in Gestant and Lactating Mammary Gland Development: A Rodent Cross-Species Microarray Transcriptomics Approach

    Directory of Open Access Journals (Sweden)

    Maricela Rodríguez-Cruz

    2013-01-01

    Full Text Available The mammary gland (MG undergoes functional and metabolic changes during the transition from pregnancy to lactation, possibly by regulation of conserved genes. The objective was to elucidate orthologous genes, chromosome clusters and putative conserved transcriptional modules during MG development. We analyzed expression of 22,000 transcripts using murine microarrays and RNA samples of MG from virgin, pregnant, and lactating rats by cross-species hybridization. We identified 521 transcripts differentially expressed; upregulated in early (78% and midpregnancy (89% and early lactation (64%, but downregulated in mid-lactation (61%. Putative orthologous genes were identified. We mapped the altered genes to orthologous chromosomal locations in human and mouse. Eighteen sets of conserved genes associated with key cellular functions were revealed and conserved transcription factor binding site search entailed possible coregulation among all eight block sets of genes. This study demonstrates that the use of heterologous array hybridization for screening of orthologous gene expression from rat revealed sets of conserved genes arranged in chromosomal order implicated in signaling pathways and functional ontology. Results demonstrate the utilization power of comparative genomics and prove the feasibility of using rodent microarrays to identification of putative coexpressed orthologous genes involved in the control of human mammary gland development.

  6. PTEN status in advanced colorectal cancer treated with cetuximab

    Science.gov (United States)

    Negri, F V; Bozzetti, C; Lagrasta, C A; Crafa, P; Bonasoni, M P; Camisa, R; Pedrazzi, G; Ardizzoni, A

    2009-01-01

    Background: Loss of phosphatase and tensin homologue deleted in chromosome 10 (PTEN) function in advanced colorectal cancer (CRC) may represent one of the resistance mechanisms to cetuximab by interfering with the epidermal growth factor receptor signal transduction pathway. Methods: PTEN expression tested by indirect immunofluorescence was evaluated both on primary (n=43) and on metastatic (n=24) sites in CRC patients treated with cetuximab. Results: The loss of PTEN expression tested on metastatic sites was negatively associated with response (100% progressive disease (PD) in PTEN-negative cases vs 30% PD in PTEN-positive cases; P<0.05), PFS (0.8 vs 8.2 months; P<0.001) and OS (2.9 vs 14.2 months; P<0.001). Conclusion: A potential role of PTEN in the anti-tumour activity of cetuximab could be hypothesised. PMID:19953097

  7. Functional Disruption of the Netrin-1 Guidance Gue Leads to Disruption in Mammary Gland Development and Increased Tumor Incidence

    Science.gov (United States)

    2005-07-01

    laminin (Fig. 6D), these alterations would occur in a ’primed’ background as breaks in basal lamina have been linked to cancer progression in the uterus ...gestation., Mech Dev 118, 191-7. Ethier, S. P., van de Velde, R. M., and Cundiff, K. C. (1989). cAMP levels in proliferating rat mammary epithelial...Granholm, A. C., Drago, J., Grinberg, A., Lee, E. J., Huang, S. P., Saarma, M., Hoffer, B. J., et al. (1996). Defects in enteric innervation and

  8. PTEN stabilizes TOP2A and regulates the DNA decatenation.

    Science.gov (United States)

    Kang, Xi; Song, Chang; Du, Xiao; Zhang, Cong; Liu, Yu; Liang, Ling; He, Jinxue; Lamb, Kristy; Shen, Wen H; Yin, Yuxin

    2015-12-10

    PTEN is a powerful tumor suppressor that antagonizes the cytoplasmic PI3K-AKT pathway and suppresses cellular proliferation. PTEN also plays a role in the maintenance of genomic stability in the nucleus. Here we report that PTEN facilitates DNA decatenation and controls a decatenation checkpoint. Catenations of DNA formed during replication are decatenated by DNA topoisomerase II (TOP2), and this process is actively monitored by a decatenation checkpoint in G2 phase. We found that PTEN deficient cells form ultra-fine bridges (UFBs) during anaphase and these bridges are generated as a result of insufficient decatenation. We show that PTEN is physically associated with a decatenation enzyme TOP2A and that PTEN influences its stability through OTUD3 deubiquitinase. In the presence of PTEN, ubiquitination of TOP2A is inhibited by OTUD3. Deletion or deficiency of PTEN leads to down regulation of TOP2A, dysfunction of the decatenation checkpoint and incomplete DNA decatenation in G2 and M phases. We propose that PTEN controls DNA decatenation to maintain genomic stability and integrity.

  9. PTEN insufficiency modulates ER+ breast cancer cell cycle progression and increases cell growth in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Chiang KC

    2015-08-01

    Full Text Available Kun-Chun Chiang,1,4 Huang-Yang Chen,1 Shu-Yuan Hsu,2 Jong-Hwei S Pang,3 Shang-Yu Wang,4 Jun-Te Hsu,4 Ta-Sen Yeh,4 Li-Wei Chen,5 Sheng-Fong Kuo,6 Chi-Chin Sun,7 Jim-Ming Lee,1 Chun-Nan Yeh,4 Horng-Heng Juang21Department of General Surgery, Chang Gung Memorial Hospital, Chang Gung University, Keelung, 2Department of Anatomy, 3Graduate Institute of Clinical Medical Sciences, 4Department of General Surgery, 5Department of Gastroenterology, 6Department of Endocrinology and Metabolism, 7Department of Ophthalmology, Chang Gung Memorial Hospital, Chang Gung University, Keelung, Taiwan, Republic of China Abstract: Phosphatase and tensin homolog (PTEN, a well-known tumor suppressor gene and frequently mutated or lost in breast cancer, possesses the negative regulation function over the PI3K/Akt/mTOR pathway. PTEN insufficiency has been associated with advanced breast cancer and poor prognosis of breast cancer patients. Recently, target therapies aimed at PI3K/Akt/mTOR pathway to treat breast cancer have got popularity. However, the exact effect of PTEN on breast cancer cells is still not well understood. This study demonstrated that PTEN knockdown in MCF-7 cells strengthened the downstream gene expressions, including p-Akt, p-ERK1/2, p-mTOR, p-p70s6k, and p-GSK3ß. PTEN knockdown MCF-7 cells had increased cell growth and Ki-67 expression. Further Western blot demonstrated that p27 was repressed obviously with p21 slightly inhibited and CDK1, 2, 4, 6, cyclin A, and Cdc25C were upregulated in MCF-7 PTEN knockdown cells, leading to the higher growth rate. More importantly, PTEN knockdown MCF-7 cells had higher tumorigenesis and tumor growth in vivo. From our current work, we provided more detailed PTEN-mediated mechanisms to stimulate ER+ breast cancer cell growth. Our result may pave the way for further target therapy development used alone or in combination with other drugs for ER+ breast cancer with PTEN insufficiency.Keywords: PTEN, breast cancer, MCF-7

  10. Comparison of the transcriptpmes of long-tern label retaining-cells and C cells microdissected from mammary epithelium: an initial study to character potential stem/progenitor cells

    Science.gov (United States)

    Mammary stem cells (MaSC) account for the cell lineage of mammary epithelia and provide for mammary growth, development and tissue homeostasis. The presence of MaSC was clearly demonstrated by the generation of an entire mammary gland from a single cell implanted into epithelium-ablated mammary fat...

  11. Plumbagin Inhibits Prostate Carcinogenesis in Intact and Castrated PTEN Knockout Mice via Targeting PKCε, Stat3, and Epithelial-to-Mesenchymal Transition Markers.

    Science.gov (United States)

    Hafeez, Bilal Bin; Fischer, Joseph W; Singh, Ashok; Zhong, Weixiong; Mustafa, Ala; Meske, Louise; Sheikhani, Mohammad Ozair; Verma, Ajit Kumar

    2015-05-01

    Prostate cancer continues to remain the most common cancer and the second leading cause of cancer-related deaths in American males. The Pten deletions and/or mutations are frequently observed in both primary prostate cancers and metastatic prostate tissue samples. Pten deletion in prostate epithelium in mice results in prostatic intraepithelial neoplasia (PIN), followed by progression to invasive adenocarcinoma. The Pten conditional knockout mice [(Pten-loxp/loxp:PB-Cre4(+)) (Pten-KO)] provide a unique preclinical model to evaluate agents for efficacy for both the prevention and treatment of prostate cancer. We present here for the first time that dietary plumbagin, a medicinal plant-derived naphthoquinone (200 or 500 ppm) inhibits tumor development in intact as well as castrated Pten-KO mice. Plumbagin has shown no signs of toxicity at either of these doses. Plumbagin treatment resulted in a decrease expression of PKCε, AKT, Stat3, and COX2 compared with the control mice. Plumbagin treatment also inhibited the expression of vimentin and slug, the markers of epithelial-to-mesenchymal transition (EMT) in prostate tumors. In summary, the results indicate that dietary plumbagin inhibits growth of both primary and castration-resistant prostate cancer (CRPC) in Pten-KO mice, possibly via inhibition of PKCε, Stat3, AKT, and EMT markers (vimentin and slug), which are linked to the induction and progression of prostate cancer.

  12. Mammary gland stem cells: More puzzles than explanations

    Indian Academy of Sciences (India)

    Suneesh Kaimala; Suneesh Kaimala; Satish Kumar

    2012-06-01

    Mammary gland stem cells (MaSC) have not been identified in spite of extensive research spanning over several decades. This has been primarily due to the complexity of mammary gland structure and its development, cell heterogeneity in the mammary gland and the insufficient knowledge about MaSC markers. At present, Lin–CD29hiCD49fhiCD24+/modSca-1– cells of the mammary gland have been reported to be enriched with MaSCs. We suggest that the inclusion of stem cell markers like Oct4, Sox2, Nanog and the mammary gland differentiation marker BRCA-1 may further narrow down the search for MaSCs. In addition, we have discussed some of the other unresolved puzzles on the mammary gland stem cells, such as their similarities and/or differences with mammary cancer stem cells, use of milk as source of mammary stem cells and the possibility of in vitro differentiation of embryonic stem (ES) cells into functional mammary gland structures in this review. Nevertheless, it is the lack of identity for a MaSC that is curtailing the advances in some of the above and other related areas.

  13. The genetic basis of Cowden's syndrome: three novel mutations in PTEN/MMAC1/TEP1.

    Science.gov (United States)

    Tsou, H C; Ping, X L; Xie, X X; Gruener, A C; Zhang, H; Nini, R; Swisshelm, K; Sybert, V; Diamond, T M; Sutphen, R; Peacocke, M

    1998-04-01

    Cowden's syndrome (CS) is an autosomal dominant disorder associated with an increased risk of developing benign and malignant tumors in a variety of tissues, including the skin, thyroid, breast and brain. Women with CS are felt to have an increased risk of developing breast cancer, and virtually all women with CS develop bilateral fibrocystic disease of the breast. Recently, a series of germline mutations have been identified from CS families in a gene known as PTEN/MMAC1/TEP1. In this study, we used heteroduplex analysis and direct sequencing analysis and identified three novel germline mutations in the PTEN/MMAC1/TEP1 coding sequence from unrelated individuals with CS. We report a de novo transition (T-->C) at nucleotide 335 in exon 5. This missense mutation resulted in a leucine to proline (CTA to CCA) change at codon 112. We also describe a novel splice site mutation (801+2T-->G) in intron 7 that caused exon skipping in PTEN/MMAC1/TEP1 mRNA. The third mutation we report is a missense mutation, consisting of a transition (T-->C) at nucleotide 202 in exon 3, resulting in a tyrosine to histidine (TAC to CAC) change at codon 68. Finally, we also detected a rare polymorphism in exon 7 of the PTEN/MMAC1/TEP1 coding sequence. These data confirm the observation that mutations of the PTEN/MMAC1/TEP1 coding sequence are responsible for at least some cases of CS, and further define the spectrum of mutations in this autosomal dominant disorder.

  14. P190B RhoGAP overexpression in the developing mammary epithelium induces TGFβ-dependent fibroblast activation.

    Directory of Open Access Journals (Sweden)

    Melissa Gillette

    Full Text Available Rho GTPases mediate stromal-epithelial interactions that are important for mammary epithelial cell (MEC morphogenesis. Increased extracellular matrix (ECM deposition and reorganization affect MEC morphogenesis in a Rho GTPase-dependent manner. Although the effects of altered ECM on MEC morphogenesis have been described, how MECs regulate stromal deposition is not well understood. Previously, we showed that p190B RhoGAP overexpression disrupts mammary gland morphogenesis by inducing hyperbranching in association with stromal alterations. We therefore hypothesized that MEC overexpression of p190B regulates paracrine interactions to impact fibroblast activation. Using a combination of in vivo morphometric and immunohistochemical analyses and primary cell culture assays, we found that p190B overexpression in MECs activates fibroblasts leading to increased collagen, fibronectin, and laminin production and elevated expression of the collagen crosslinking enzyme lysyl oxidase. Phosphorylation of the TGF-β effector SMAD2 and expression of the TGF-β target gene αSma were increased in p190B-associated fibroblasts, suggesting that elevated TGF-β signaling promoted fibroblast activation. Mechanical tension and TGF-β cooperate to activate fibroblasts. Interestingly, active TGF-β was elevated in conditioned medium from p190B overexpressing MECs compared to control MECs, and p190B overexpressing MECs exhibited increased contractility in a collagen gel contraction assay. These data suggest that paracrine signaling from the p190B overexpressing MECs may activate TGF-β signaling in adjacent fibroblasts. In support of this, transfer of conditioned medium from p190B overexpressing MECs onto wildtype fibroblasts or co-culture of p190B overexpressing MECs with wildtype fibroblasts increased SMAD2 phosphorylation and mRNA expression of ECM genes in the fibroblasts when compared to fibroblasts treated with control CM or co-cultured with control MECs. The

  15. ROLES OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF-A) IN MEDIATION OF DIOXIN (TCDD)-INDUCED DELAYS IN DEVELOPMENT OF THE MOUSE MAMMARY GLAND

    Science.gov (United States)

    Roles of Epidermal Growth Factor (EGF) and Transforming Growth Factor-alpha (TGF-a) in Mediation of Dioxin (TCDD)-Induced Delays in Development of the Mouse Mammary Gland.Suzanne E. Fenton, Barbara Abbott, Lamont Bryant, and Angela Buckalew. U.S. EPA, NHEERL, Reproductive Tox...

  16. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis

    OpenAIRE

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; MIN, KYUENG-WHAN; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-01-01

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in th...

  17. Functional and gene network analyses of transcriptional signatures characterizing pre-weaned bovine mammary parenchyma or fat pad uncovered novel inter-tissue signaling networks during development

    Directory of Open Access Journals (Sweden)

    Lewin Harris A

    2010-05-01

    determining the biological features of MFP and PAR during neonatal development. This was exemplified by the potential effect that the signaling molecules (cytokines, growth factors released preferentially (i.e., more highly-expressed by PAR or MFP could have on molecular functions or signaling pathways enriched in the MFP or PAR. These bidirectional interactions might be required to coordinate mammary tissue development under normal circumstances or in response to nutrition.

  18. Effect of Thyroid Function on MNU-Induced Mammary Carcinogenesis.

    Science.gov (United States)

    Vermey, Mackenzie L; Marks, Gregory T; Baldridge, Monika G

    2015-06-01

    Mammary cancer is a disease that affects many women. Extensive research has been conducted to elucidate which variables are involved in the development of this cancer. Studies have highlighted thyroid function as a modulator of tumor growth and development. Thyroxine and 3,3',5-triiodothyronine are responsible for regulating the development, differentiation, homeostasis, and metabolism of cells in the body including mammary tissue. Thyroid hormones also have estrogen-like effects on mammary cancer cell growth by regulating the estrogen receptor. The present study was designed to determine whether medically induced hyperthyroidism increases the multiplicity, prevalence, and mammary tumor burden in rats; and to elucidate whether surgically induced hypothyroidism conversely attenuates the rate of mammary cancer cell growth. Female Sprague-Dawley rats were randomly divided into three groups (euthyroid-control, hyperthyroid, and hypothyroid). Hyperthyroidism was induced via oral administration of levothyroxine; whereas, hypothyroidism was induced by thyroidectomy. Mammary carcinogenesis was induced with a single intraperitoneal injection of N-methyl-N-nitrosurea (MNU). Rats were sacrificed at 38 weeks, and the mammary tumors were excised, fixed for histology and analyzed. Analysis included evaluation of malignancy and immunohistochemistry for ER. MNU-induced mammary carcinogenesis among the groups resulted in a significant difference in tumor burden. The hyperthyroid group had a statistically higher tumor burden than did the euthyroid group, and the hypothyroid group had no tumors of mammary tissue origin at 38 weeks. All excised mammary tumors were ER alpha negative. These data support the hypothesis that thyroid function is one of potentially many factors that contribute to modulation of MNU-induced mammary tumor growth.

  19. Genetic and cell biological aspects of PTEN in prostate cancer

    NARCIS (Netherlands)

    P.W. van Duijn (Petra)

    2008-01-01

    textabstractThe dual specific phosphatase PTEN (Phosphatase and TENsin homolog deleted on chromosome 10) is one of the most extensively studied proteins of the last decade. It was the first phosphatase identified as a tumor suppressor and in sporadic cancers PTEN is one of the most frequently altere

  20. MyosinV controls PTEN function and neuronal cell size.

    Science.gov (United States)

    van Diepen, Michiel T; Parsons, Maddy; Downes, C Peter; Leslie, Nicholas R; Hindges, Robert; Eickholt, Britta J

    2009-10-01

    The tumour suppressor PTEN can inhibit cell proliferation and migration as well as control cell growth, in different cell types. PTEN functions predominately as a lipid phosphatase, converting PtdIns(3,4,5)P(3) to PtdIns(4,5)P(2), thereby antagonizing PI(3)K (phosphoinositide 3-kinase) and its established downstream effector pathways. However, much is unclear concerning the mechanisms that regulate PTEN movement to the cell membrane, which is necessary for its activity towards PtdIns(3,4,5)P(3) (Refs 3, 4, 5). Here we show a requirement for functional motor proteins in the control of PI3K signalling, involving a previously unknown association between PTEN and myosinV. FRET (Förster resonance energy transfer) measurements revealed that PTEN interacts directly with myosinV, which is dependent on PTEN phosphorylation mediated by CK2 and/or GSK3. Inactivation of myosinV-transport function in neurons increased cell size, which, in line with known attributes of PTEN-loss, required PI(3)K and mTor. Our data demonstrate a myosin-based transport mechanism that regulates PTEN function, providing new insights into the signalling networks regulating cell growth.

  1. A unified nomenclature and amino acid numbering for human PTEN

    NARCIS (Netherlands)

    Pulido, Rafael; Baker, Suzanne J; Barata, Joao T; Carracedo, Arkaitz; Cid, Victor J; Chin-Sang, Ian D; Davé, Vrushank; den Hertog, Jeroen; Devreotes, Peter; Eickholt, Britta J; Eng, Charis; Furnari, Frank B; Georgescu, Maria-Magdalena; Gericke, Arne; Hopkins, Benjamin; Jiang, Xeujun; Lee, Seung-Rock; Lösche, Mathias; Malaney, Prerna; Matias-Guiu, Xavier; Molina, María; Pandolfi, Pier Paolo; Parsons, Ramon; Pinton, Paolo; Rivas, Carmen; Rocha, Rafael M; Rodríguez, Manuel S; Ross, Alonzo H; Serrano, Manuel; Stambolic, Vuk; Stiles, Bangyan; Suzuki, Akira; Tan, Seong-Seng; Tonks, Nicholas K; Trotman, Lloyd C; Wolff, Nicolas; Woscholski, Rudiger; Wu, Hong; Leslie, Nicholas R

    2014-01-01

    The tumor suppressor PTEN is a major brake for cell transformation, mainly due to its phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3] phosphatase activity that directly counteracts the oncogenicity of phosphoinositide 3-kinase (PI3K). PTEN mutations are frequent in tumors and in the germ line

  2. A unified nomenclature and amino acid numbering for human PTEN

    NARCIS (Netherlands)

    Pulido, Rafael; Baker, Suzanne J; Barata, Joao T; Carracedo, Arkaitz; Cid, Victor J; Chin-Sang, Ian D; Davé, Vrushank; den Hertog, Jeroen; Devreotes, Peter; Eickholt, Britta J; Eng, Charis; Furnari, Frank B; Georgescu, Maria-Magdalena; Gericke, Arne; Hopkins, Benjamin; Jiang, Xeujun; Lee, Seung-Rock; Lösche, Mathias; Malaney, Prerna; Matias-Guiu, Xavier; Molina, María; Pandolfi, Pier Paolo; Parsons, Ramon; Pinton, Paolo; Rivas, Carmen; Rocha, Rafael M; Rodríguez, Manuel S; Ross, Alonzo H; Serrano, Manuel; Stambolic, Vuk; Stiles, Bangyan; Suzuki, Akira; Tan, Seong-Seng; Tonks, Nicholas K; Trotman, Lloyd C; Wolff, Nicolas; Woscholski, Rudiger; Wu, Hong; Leslie, Nicholas R

    2014-01-01

    The tumor suppressor PTEN is a major brake for cell transformation, mainly due to its phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3] phosphatase activity that directly counteracts the oncogenicity of phosphoinositide 3-kinase (PI3K). PTEN mutations are frequent in tumors and in the germ line

  3. Effects of soy-derived isoflavones and a high-fat diet on spontaneous mammary rimor development in Tg.NK (MMTV/c-neu) mice

    DEFF Research Database (Denmark)

    Luijten, M.; Thomsen, A.R.; van den Berg, J.A.H.

    2004-01-01

    Phytoestrogens such as isoflavonoids and lignans have been postulated as breast cancer protective constituents in soy and whole-grain cereals. We investigated the ability of isoflavones (IFs) and flaxseed to modulate spontaneous mammary tumor development in female heterozygous Tg.NK (MMTV....../c-neu) mice. Two different exposure protocols were applied, either from 4 wk of age onward (postweaning) or during gestation and lactation (perinatal). In the postweaning exposure study, mice were fed IFs or flaxseed in a high-fat diet. In addition, flaxseed in a low-fat diet was tested. Postweaning exposure...... at necropsy in the perinatal exposure study was significantly increased in the medium- and high-IF dose groups. Comparison of both exposure scenarios revealed a strongly accelerated onset of tumor growth after perinatal high-fat diet exposure compared with the low-fat diet. This study shows that breast cancer...

  4. PTEN-PDZ domain interactions: Binding of PTEN to PDZ domains of PTPN13.

    NARCIS (Netherlands)

    Sotelo, N.S.; Schepens, J.T.G.; Valiente, M.; Hendriks, W.J.A.J.; Pulido, R.

    2015-01-01

    Protein modular interactions mediated by PDZ domains are essential for the establishment of functional protein networks controlling diverse cellular functions. The tumor suppressor PTEN possesses a C-terminal PDZ-binding motif (PDZ-BM) that is recognized by a specific set of PDZ domains from scaffol

  5. Stem cells in normal mammary gland and breast cancer.

    Science.gov (United States)

    Luo, Jie; Yin, Xin; Ma, Tao; Lu, Jun

    2010-04-01

    The mammary gland is a structurally dynamic organ that undergoes dramatic alterations with age, menstrual cycle, and reproductive status. Mammary gland stem cells, the minor cell population within the mature organ, are thought to have multiple functions in regulating mammary gland development, tissue maintenance, major growth, and structural remodeling. In addition, accumulative evidence suggests that breast cancers are initiated and maintained by a subpopulation of tumor cells with stem cell features (called cancer stem cells). A variety of methods have been developed to identify and characterize mammary stem cells, and several signal transduction pathways have been identified to be essential for the self-renewal and differentiation of mammary gland stem cells. Understanding the origin of breast cancer stem cells, their relationship to breast cancer development, and the differences between normal and cancer stem cells may lead to novel approaches to breast cancer diagnosis, prevention, and treatment.

  6. Simultaneous inactivation of Par-4 and PTEN in vivo leads to synergistic NF-κB activation and invasive prostate carcinoma

    Science.gov (United States)

    Fernandez-Marcos, Pablo J.; Abu-Baker, Shadi; Joshi, Jayashree; Galvez, Anita; Castilla, Elias A.; Cañamero, Marta; Collado, Manuel; Saez, Carmen; Moreno-Bueno, Gema; Palacios, Jose; Leitges, Michael; Serrano, Manuel; Moscat, Jorge; Diaz-Meco, Maria T.

    2009-01-01

    Prostate cancer is one of the most common neoplasias in men. The tumor suppressor Par-4 is an important negative regulator of the canonical NF-κB pathway and is highly expressed in prostate. Here we show that Par-4 expression is lost in a high percentage of human prostate carcinomas, and this occurs in association with phosphatase and tensin homolog deleted from chromosome 10 (PTEN) loss. Par-4 null mice, similar to PTEN-heterozygous mice, only develop benign prostate lesions, but, importantly, concomitant Par-4 ablation and PTEN-heterozygosity lead to invasive prostate carcinoma in mice. This strong tumorigenic cooperation is anticipated in the preneoplastic prostate epithelium by an additive increase in Akt activation and a synergistic stimulation of NF-κB. These results establish the cooperation between Par-4 and PTEN as relevant for the development of prostate cancer and implicate the NF-κB pathway as a critical event in prostate tumorigenesis. PMID:19470463

  7. Binding of PTEN to specific PDZ domains contributes to PTEN protein stability and phosphorylation by microtubule-associated serine/threonine kinases.

    Science.gov (United States)

    Valiente, Miguel; Andrés-Pons, Amparo; Gomar, Beatriz; Torres, Josema; Gil, Anabel; Tapparel, Caroline; Antonarakis, Stylianos E; Pulido, Rafael

    2005-08-12

    The tumor suppressor phosphatase PTEN is a key regulator of cell growth and apoptosis that interacts with PDZ domains from regulatory proteins, including MAGI-1/2/3, hDlg, and MAST205. Here we identified novel PTEN-binding PDZ domains within the MAST205-related proteins, syntrophin-associated serine/threonine kinase and MAST3, characterized the regions of PTEN involved in its interaction with distinctive PDZ domains, and analyzed the functional consequences on PTEN of PDZ domain binding. Using a panel of PTEN mutations, as well as PTEN chimeras containing distinct domains of the related protein TPTE, we found that the PTP and C2 domains of PTEN do not affect PDZ domain binding and that the C-terminal tail of PTEN (residues 350-403) provides selectivity to recognize specific PDZ domains from MAGI-2, hDlg, and MAST205. Binding of PTEN to the PDZ-2 domain from MAGI-2 increased PTEN protein stability. Furthermore, binding of PTEN to the PDZ domains from microtubule-associated serine/threonine kinases facilitated PTEN phosphorylation at its C terminus by these kinases. Our results suggest an important role for the C-terminal region of PTEN in the selective association with scaffolding and/or regulatory molecules and provide evidence that PDZ domain binding stabilizes PTEN and targets this tumor suppressor for phosphorylation by microtubule-associated serine/threonine kinases.

  8. Developmental signaling pathways regulating mammary stem cells and contributing to the etiology of triple-negative breast cancer

    OpenAIRE

    Rangel,Maria Cristina; Bertolette, Daniel; Castro, Nadia P.; Klauzinska, Malgorzata; Cuttitta, Frank; Salomon, David S

    2016-01-01

    Cancer has been considered as temporal and spatial aberrations of normal development in tissues. Similarities between mammary embryonic development and cell transformation suggest that the underlying processes required for mammary gland development are also those perturbed during various stages of mammary tumorigenesis and breast cancer (BC) development. The master regulators of embryonic development Cripto-1, Notch/CSL, and Wnt/β-catenin play key roles in modulating mammary gland morphogenes...

  9. A single-copy Sleeping Beauty transposon mutagenesis screen identifies new PTEN-cooperating tumor suppressor genes.

    Science.gov (United States)

    de la Rosa, Jorge; Weber, Julia; Friedrich, Mathias Josef; Li, Yilong; Rad, Lena; Ponstingl, Hannes; Liang, Qi; de Quirós, Sandra Bernaldo; Noorani, Imran; Metzakopian, Emmanouil; Strong, Alexander; Li, Meng Amy; Astudillo, Aurora; Fernández-García, María Teresa; Fernández-García, María Soledad; Hoffman, Gary J; Fuente, Rocío; Vassiliou, George S; Rad, Roland; López-Otín, Carlos; Bradley, Allan; Cadiñanos, Juan

    2017-03-20

    The overwhelming number of genetic alterations identified through cancer genome sequencing requires complementary approaches to interpret their significance and interactions. Here we developed a novel whole-body insertional mutagenesis screen in mice, which was designed for the discovery of Pten-cooperating tumor suppressors. Toward this aim, we coupled mobilization of a single-copy inactivating Sleeping Beauty transposon to Pten disruption within the same genome. The analysis of 278 transposition-induced prostate, breast and skin tumors detected tissue-specific and shared data sets of known and candidate genes involved in cancer. We validated ZBTB20, CELF2, PARD3, AKAP13 and WAC, which were identified by our screens in multiple cancer types, as new tumor suppressor genes in prostate cancer. We demonstrated their synergy with PTEN in preventing invasion in vitro and confirmed their clinical relevance. Further characterization of Wac in vivo showed obligate haploinsufficiency for this gene (which encodes an autophagy-regulating factor) in a Pten-deficient context. Our study identified complex PTEN-cooperating tumor suppressor networks in different cancer types, with potential clinical implications.

  10. Systems biology reveals new strategies for personalizing cancer medicine and confirms the role of PTEN in resistance to trastuzumab.

    Science.gov (United States)

    Faratian, Dana; Goltsov, Alexey; Lebedeva, Galina; Sorokin, Anatoly; Moodie, Stuart; Mullen, Peter; Kay, Charlene; Um, In Hwa; Langdon, Simon; Goryanin, Igor; Harrison, David J

    2009-08-15

    Resistance to targeted cancer therapies such as trastuzumab is a frequent clinical problem not solely because of insufficient expression of HER2 receptor but also because of the overriding activation states of cell signaling pathways. Systems biology approaches lend themselves to rapid in silico testing of factors, which may confer resistance to targeted therapies. Inthis study, we aimed to develop a new kinetic model that could be interrogated to predict resistance to receptor tyrosine kinase (RTK) inhibitor therapies and directly test predictions in vitro and in clinical samples. The new mathematical model included RTK inhibitor antibody binding, HER2/HER3 dimerization and inhibition, AKT/mitogen-activated protein kinase cross-talk, and the regulatory properties of PTEN. The model was parameterized using quantitative phosphoprotein expression data from cancer cell lines using reverse-phase protein microarrays. Quantitative PTEN protein expression was found to be the key determinant of resistance to anti-HER2 therapy in silico, which was predictive of unseen experiments in vitro using the PTEN inhibitor bp(V). When measured in cancer cell lines, PTEN expression predicts sensitivity to anti-HER2 therapy; furthermore, this quantitative measurement is more predictive of response (relative risk, 3.0; 95% confidence interval, 1.6-5.5; P biology approach has successfully been used to stratify patients for personalized therapy in cancer and is further compelling evidence that PTEN, appropriately measured in the clinical setting, refines clinical decision making in patients treated with anti-HER2 therapies.

  11. Clinical Implications for Germline PTEN Spectrum Disorders.

    Science.gov (United States)

    Ngeow, Joanne; Sesock, Kaitlin; Eng, Charis

    2017-06-01

    Patients with PTEN hamartoma tumor syndrome (PHTS) may present to a variety of different subspecialties with benign and malignant clinical features. They have increased lifetime risks of breast, endometrial, thyroid, renal, and colon cancers, as well as neurodevelopmental disorders such as autism spectrum disorder. Patients and affected family members can be offered gene-directed surveillance and management. Patients who are unaffected can be spared unnecessary investigations. With longitudinal follow-up, we are likely to identify other non-cancer manifestations associated with PHTS such as metabolic, immunologic, and neurologic features. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development.

    Science.gov (United States)

    Perri, A F; Dallard, B E; Baravalle, C; Licoff, N; Formía, N; Ortega, H H; Becú-Villalobos, D; Mejia, M E; Lacau-Mengido, I M

    2014-01-01

    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.

  13. Broccoli, PTEN deletion and prostate cancer: where is the link?

    Directory of Open Access Journals (Sweden)

    Bardelli Alberto

    2010-12-01

    Full Text Available Abstract The concept that vegetables and fruits are relevant sources of cancer-preventive substances is strongly supported by population studies. Among others, cruciferous vegetables like broccoli, cabbage, cauliflower and Brussels sprouts are thought to affect the development of various types of cancers and especially prostate tumors. Yet, the identification of the molecular mechanisms by which the 'active' compounds contained in these vegetables mediate their anticancer activity has historically lagged behind. Accordingly, direct laboratory evidence of how individual nutrients affect cancer genes and the pathways they control remains the major obstacle to progress in this research field. Here we review a recent report investigating the interaction between sulforaphane, a dietary isothiocyanate derived from broccoli, and expression of the PTEN tumor suppressor gene in pre malignant prostate tissue.

  14. Identification of rat mammary tumor-1 gene (RMT-1), which is highly expressed in rat mammary tumors.

    Science.gov (United States)

    Chiou, S; Yoo, J; Loh, K C; Guzman, R C; Gopinath, G R; Rajkumar, L; Chou, Y C; Yang, J; Popescu, N C; Nandi, S

    2001-12-10

    Full-term pregnancy early in life results in a permanent reduction in lifetime breast cancer risk in women. Parous rats and mice are also refractory to chemical carcinogenesis. Therefore, investigation of the differences between mammary glands from virgin and parous rats would provide valuable information regarding the protective effects of early full-term pregnancy. In this report, we examined the gene expression patterns in mammary glands from virgin and parous Lewis rats. Using differential display technology, a novel 4.2 kb cDNA, designated rat mammary tumor-1 (RMT-1) was isolated. Northern blot analysis of RMT-1 showed that RMT-1 expression was higher in the pre-pubertal and pubertal stages during rat mammary gland development while it was down-regulated in mammary glands from mature virgin and parous rats. RMT-1 expression was highest in rat mammary cancers compared with either the mammary glands of virgin or parous rats. At the Northern blot sensitivity level, RMT-1 expression was found only in the mammary gland. Northern blot analysis also showed that the expression of this gene was found in 74% of N-methyl-nitrosourea (MNU)-induced mammary cancers while it was not found in MNU-induced cancers from other organs. The examination of the RMT-1 gene structure revealed that it consists of five exons spanning 5.9 kb. Using fluorescence in situ hybridization, the gene was localized on rat chromosome 1 band q 43-51. The present data show that there is a correlation between high RMT-1 expression and rat mammary carcinogenesis or decreased RMT-1 expression and parity associated refractoriness to chemically induced mammary carcinogenesis. However, whether or not RMT-1 gene has a functional role in these processes remains to be investigated.

  15. New insights into the dual recruitment of IgA+ B cells in the developing mammary gland.

    Science.gov (United States)

    Bourges, Dorothée; Meurens, François; Berri, Mustapha; Chevaleyre, Claire; Zanello, Galliano; Levast, Benoît; Melo, Sandrine; Gerdts, Volker; Salmon, Henri

    2008-07-01

    In monogastric mammals, transfer of passive immunity via milk and colostrum plays an important role in protecting the neonate against mucosal infections. Here we analyzed the hypothesis that during gestation/lactation IgA+ plasmablasts leave the intestinal and respiratory surfaces towards the mammary gland (MG). We compared the recruitment of lymphocytes expressing homing receptors alpha4beta1 and alpha4beta7 to expression of their vascular counter-receptors, VCAM-1 and MAdCAM-1. Furthermore, the expression of the chemokines responsible for the recruitment of IgA+ plasmablasts was analyzed. Data confirmed that expressions of CCL28 and MAdCAM-1 in the MG increased during pregnancy and alpha4beta1+ and alpha4beta7+/IgA+ cell recruitment in lactation correlated with increase of CCL28 expression. Interestingly, VCAM-1 expression was found in small blood vessels of the lactating porcine MG, while in mice VCAM-1 was expressed in large blood vessels within the MG. Thus, our results indicate that the recruitment of IgA+ plasmablasts to MG is mediated by VCAM-1/alpha4beta1 and MAdCAM-1/alpha4beta7 in conjunction with CCL28/CCR10. They support the existence of a functional link between entero- and upper respiratory surfaces and MG, thereby, conferring protection against aero-digestive pathogens in the newborn.

  16. P-Cadherin Expression in Feline Mammary Tissues

    Directory of Open Access Journals (Sweden)

    Ana Catarina Figueira

    2012-01-01

    Full Text Available The search for molecular markers in the feline mammary gland, namely, the adhesion molecules belonging to the cadherin family, is useful in the understanding of the development of mammary carcinomas in felines and humans. To study P-cadherin expression in the feline mammary gland, 61 samples of normal (n=4, hyperplastic (n=12, and neoplastic (n=45 feline mammary tissues were examined. In both normal and hyperplastic mammary tissues as well as in benign tumours, P-cadherin immunolabelling was restricted to myoepithelial cells. In malignant tumours, however, there was an aberrant epithelial P-cadherin immunoexpression in 64.1% (n=25 of cases, with a membranous and/or cytoplasmic pattern of distribution. A statistically significant relationship was seen between epithelial P-cadherin expression and malignant mammary lesions (P=0.0001. In malignant mammary tumours, there was likewise a statistically significant relationship between aberrant P-cadherin immunoexpression and histological grade (P=0.0132. Aberrant epithelial P-cadherin expression seems to be related to malignancy in the feline mammary gland. To confirm the results of this investigation, further studies with larger samples and follow-up studies are warranted.

  17. Phosphorylation of PTEN at STT motif is associated with DNA damage response

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Sandip; Mukherjee, Ananda; Karmakar, Parimal, E-mail: pkarmakar_28@yahoo.co.in

    2014-12-15

    Highlights: • Phosphorylation PTEN at the C-terminal STT motif is necessary for DNA repair. • DNA damage induces phosphorylation of STT motif of PTEN. • Phospho-PTEN translocates to nucleus after DNA damage. • Phospho-PTEN forms nuclear foci after DNA damage which co localized with γH2AX. - Abstract: Phosphatase and tensin homolog deleted on chromosome Ten (PTEN), a tumor suppressor protein participates in multiple cellular activities including DNA repair. In this work we found a relationship between phosphorylation of carboxy (C)-terminal STT motif of PTEN and DNA damage response. Ectopic expression of C-terminal phospho-mutants of PTEN, in PTEN deficient human glioblastoma cells, U87MG, resulted in reduced viability and DNA repair after etoposide induced DNA damage compared to cells expressing wild type PTEN. Also, after etoposide treatment phosphorylation of PTEN increased at C-terminal serine 380 and threonine 382/383 residues in PTEN positive HEK293T cells and wild type PTEN transfected U87MG cells. One-step further, DNA damage induced phosphorylation of PTEN was confirmed by immunoprecipitation of total PTEN from cellular extract followed by immunobloting with phospho-specific PTEN antibodies. Additionally, phospho-PTEN translocated to nucleus after etoposide treatment as revealed by indirect immunolabeling. Further, phosphorylation dependent nuclear foci formation of PTEN was observed after ionizing radiation or etoposide treatment which colocalized with γH2AX. Additionally, etoposide induced γH2AX, Mre11 and Ku70 foci persisted for a longer period of times in U87MG cells after ectopic expression of PTEN C-terminal phospho-mutant constructs compared to wild type PTEN expressing cells. Thus, our findings strongly suggest that DNA damage induced phosphorylation of C-terminal STT motif of PTEN is necessary for DNA repair.

  18. Of Microenvironments and Mammary Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    LaBarge, Mark A; Petersen, Ole W; Bissell, Mina J

    2007-06-01

    In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion and directs their critical functions. Thus guided, stem cells are able to maintain tissue homeostasis throughout the ebb and flow of metabolic and physical demands encountered over a lifetime. Indeed, a pool of stem cells maintains mammary gland structure throughout development, and responds to the physiological demands associated with pregnancy. This review discusses how stem cells were identified in both human and mouse mammary glands; each requiring different techniques that were determined by differing biological needs and ethical constraints. These studies together create a robust portrait of mammary gland biology and identify the location of the stem cell niche, elucidate a developmental hierarchy, and suggest how the niche might be manipulated for therapeutic benefit.

  19. PCR-SSCP-DNA sequencing method in detecting PTEN gene mutation and its significance in human gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Chuan-Yong Guo; Xuan-Fu Xu; Jian-Ye Wu; Shu-Fang Liu

    2008-01-01

    AIM: To discuss the possible effect of PTEN gene mutations on occurrence and development of gastric cancer.METHODS: Fifty-three gastric cancer specimens were selected to probe PTEN gene mutations in genome of gastric cancer and paracancerous tissues using PCR-SSCP-DNA sequencing method based on microdissection and to observe the protein expression by immunohistochemistry technique.RESULTS: PCR-SSCP-DNA sequencing indicated that 4 kinds of mutation sites were found in 5 of 53 gastric cancer specimens.One kind of mutation was found in exons.AA-TCC mutation was located at 40bp upstream of 3' lateral exert 7 (115946 AA-TCC).Such mutations led to terminator formation in the 297th codon of the PTEN gene.The other 3 kinds of mutation were found in introns,including a G-C point mutation at 91 bp upstream of 5' lateral exon 5(90896 G-C),a T-G point mutation at 24 bp upstream of 5' lateral exon 5 (90963 T-G),and a single base A mutation at 7 bp upstream of 5' lateral exon 5 (90980 A del).The PTEN protein expression in gastric cancer and paracancerous tissues detected using immunohistochemistry technique indicated that the total positive rate of PTEN protein expression was 66% in gastric cancer tissue,which was significantly lower than that (100%) in paracancerous tissues (P<0.005).CONCLUSION: PTEN gene mutation and expression may play an important role in the occurrence and development of gastric cancer.(C)2008 The WJG Press.All rights reserved.

  20. WWP2 and its association with PTEN in endometrial cancer

    Directory of Open Access Journals (Sweden)

    Aine E. Clements

    2015-08-01

    We found that in tumors with low PTEN protein but normal mRNA expression there were significantly higher levels of WWP2 expression (p = 0.0017. Increased WWP2 expression was not associated with clinical prognostic factors including lymphovascular space invasion, ≥50% myometrial invasion, grade, stage or recurrence. WWP2 expression was not different statistically between tumors and normal controls (p = NS. Therefore, in this cohort, tumors with low PTEN protein but normal mRNA expression had elevated levels of WWP2 expression. This suggests that WWP2 may be playing a role in PTEN degradation in endometrial cancer.

  1. Characterization of the Six1 homeobox gene in normal mammary gland morphogenesis

    Directory of Open Access Journals (Sweden)

    McManaman James L

    2010-01-01

    Full Text Available Abstract Background The Six1 homeobox gene is highly expressed in the embryonic mammary gland, continues to be expressed in early postnatal mammary development, but is lost when the mammary gland differentiates during pregnancy. However, Six1 is re-expressed in breast cancers, suggesting that its re-instatement in the adult mammary gland may contribute to breast tumorigenesis via initiating a developmental process out of context. Indeed, recent studies demonstrate that Six1 overexpression in the adult mouse mammary gland is sufficient for initiating invasive carcinomas, and that its overexpression in xenograft models of mammary cancer leads to metastasis. These data demonstrate that Six1 is causally involved in both breast tumorigenesis and metastasis, thus raising the possibility that it may be a viable therapeutic target. However, because Six1 is highly expressed in the developing mammary gland, and because it has been implicated in the expansion of mammary stem cells, targeting Six1 as an anti-cancer therapy may have unwanted side effects in the breast. Results We sought to determine the role of Six1 in mammary development using two independent mouse models. To study the effect of Six1 loss in early mammary development when Six1 is normally expressed, Six1-/- embryonic mammary glands were transplanted into Rag1-/- mice. In addition, to determine whether Six1 downregulation is required during later stages of development to allow for proper differentiation, we overexpressed Six1 during adulthood using an inducible, mammary-specific transgenic mouse model. Morphogenesis of the mammary gland occurred normally in animals transplanted with Six1-/- embryonic mammary glands, likely through the redundant functions of other Six family members such as Six2 and Six4, whose expression was increased in response to Six1 loss. Surprisingly, inappropriate expression of Six1 in the adult mammary gland, when levels are normally low to absent, did not inhibit

  2. Loss of SOX9 Expression Is Associated with PSA Recurrence in ERG-Positive and PTEN Deleted Prostate Cancers.

    Directory of Open Access Journals (Sweden)

    Christoph Burdelski

    Full Text Available The transcription factor SOX9 plays a crucial role in normal prostate development and has been suggested to drive prostate carcinogenesis in concert with PTEN inactivation. To evaluate the clinical impact of SOX9 and its relationship with key genomic alterations in prostate cancer, SOX9 expression was analyzed by immunohistochemistry on a tissue microarray containing 11,152 prostate cancers. Data on ERG status and deletions of PTEN, 3p13, 5q21 and 6q15 were available from earlier studies. SOX9 expression levels were comparable in luminal cells of normal prostate glands (50% SOX9 positive and 3,671 cancers lacking TMPRSS2:ERG fusion (55% SOX9 positive, but was markedly increased in 3,116 ERG-fusion positive cancers (81% SOX9 positive, p<0.0001. While no unequivocal changes in the SOX9 expression levels were found in different stages of ERG-negative cancers, a gradual decrease of SOX9 paralleled progression to advanced stage, high Gleason grade, metastatic growth, and presence of PTEN deletions in ERG-positive cancers (p<0.0001 each. SOX9 levels were unrelated to deletions of 3p, 5q, and 6q. Down-regulation of SOX9 expression was particularly strongly associated with PSA recurrence in ERG-positive tumors harboring PTEN deletions (p=0.001, but had no significant effect in ERG-negative cancers or in tumors with normal PTEN copy numbers. In summary, the results of our study argue against a tumor-promoting role of SOX9 in prostate cancer, but demonstrate that loss of SOX9 expression characterizes a particularly aggressive subset of ERG positive cancers harboring PTEN deletions.

  3. Human mammary fibroblasts stimulate invasion of breast cancer cells in a three-dimensional culture and increase stroma development in mouse xenografts

    Directory of Open Access Journals (Sweden)

    Olsen Charlotta J

    2010-08-01

    Full Text Available Abstract Introduction Tumour phenotype is regulated in a complex fashion as a result of interactions between malignant cells and the tumour stroma. Fibroblasts are the most abundant and perhaps most active part of the tumour stroma. A better understanding of the changes that occur in fibroblasts in response to the presence of malignant cells may lead to the development of new strategies for cancer treatment. We explored the effects of fibroblasts on the growth and invasion of mammary carcinoma tumour cells in vitro and in vivo. Methods In order to analyse secreted factors that affect invasive abilities of breast cancer cells we co-cultured human mammary fibroblasts (HMF3s and cancer cells (MCF7S1 in three-dimensional (3D growth conditions devoid of heterogeneous cell-cell contact. To study the possible influence of fibroblasts on MCF7S1 cancer cell growth in vivo we co-injected HMF3s and MCF7S1 cells in Balb/c nu/nu mice. Results In 3D co-culture both HMF3s and MCF7S1 cells demonstrated enhanced invasion into a Matrigel matrix. This was correlated with enhanced expression of the metastasis promoting S100A4 protein in fibroblasts, stimulation of the matrix metalloproteinase (MMP-2 activity, and enhanced secretion of a range of different cytokines. Orthotopic injection of oestrogen-dependent MCF7S1 cancer cells together with fibroblasts showed stimulation of tumour growth in mice without an external oestrogen supply. The resulting tumours were characterized by increased development of extracellular matrix, as well as an increase of murine S100A4 concentration and activity of MMP-2 in the tumour interstitial fluid. Conclusion Stimulation of the invasive phenotype of tumour cells in 3D co-cultures with fibroblasts could be correlated with increased production of S100A4 and MMP-2. We propose that enhanced development of mouse host-derived tumour stroma in a MCF7S1 co-injection xenograft model leads to oestrogen independency and is triggered by the

  4. Canine mammary gland tumors.

    Science.gov (United States)

    Sorenmo, Karin

    2003-05-01

    The National Consensus Group recommends that all women with tumors larger than 1 cm be offered chemotherapy regardless of tumor histology of lymph node status. This recommendation is to ensure that everyone at risk for failing, even though the risk may be low in women with relatively small tumors and favorable histology, has a choice and receives the benefit of adjuvant chemotherapy. This type of treatment recommendation may also be made in dogs based on recognized, well-accepted prognostic factors such as tumor size, stage, type, and histologic differentiation. Based on the limited clinical information available in veterinary medicine, the drugs that are effective in human breast cancer, such as cyclophosphamide, 5-fluorouracil, and doxorubicin, may also have a role in the treatment of malignant mammary gland tumors in dogs. Randomized prospective studies are needed, however, to evaluate the efficacy of chemotherapy in dogs with high-risk mammary gland tumors and to determine which drugs and protocols are the most efficacious. Until such studies are performed, the treatment of canine mammary gland tumors will be based on the individual oncologist's understanding of tumor biology, experience, interpretation of the available studies, and a little bit of gut-feeling. Table 2 is a proposal for treatment guidelines for malignant canine mammary gland tumors according to established prognostic factors, results from published veterinary studies, and current recommendations for breast cancer treatment in women.

  5. Immunoglobins in mammary secretions

    DEFF Research Database (Denmark)

    Hurley, W L; Theil, Peter Kappel

    2013-01-01

    Immunoglobulins secreted in colostrum and milk by the lactating mammal are major factors providing immune protection to the newborn. Immunoglobulins in mammary secretions represent the cumulative immune response of the lactating animal to exposure to antigenic stimulation that occurs through inte...

  6. DNA methylation of PTEN gene promoter region is not correlated ...

    African Journals Online (AJOL)

    Yomi

    2012-02-23

    Feb 23, 2012 ... Key words: PTEN, promoter methylation, bladder cancer. INTRODUCTION ... al., 2005), pancreatic cancer (Asano et al., 2004), thyroid cancer (Frisk et al., ..... papillary mucinous neoplasms of the pancreas. J. Hepatobiliary.

  7. Caffeine activates tumor suppressor PTEN in sarcoma cells

    OpenAIRE

    Miwa, Shinji; Sugimoto, Naotoshi; Shirai, Toshiharu; Hayashi, Katsuhiro; Nishida, Hideji; Ohnari, Issei; Takeuchi, Akihiko; Yachie, Akihiro; Tsuchiya, Hiroyuki

    2011-01-01

    The tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a negative regulator of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Akt activation exerts a strong anti-apoptotic effect and inhibits key pro-apoptotic proteins. We investigated the effect of caffeine in the prevention of tumor cell proliferation and induction of cell death. We found that caffeine induced increased intracellular cAMP levels, PTEN activation and Akt inactivation, which to...

  8. Molecular Analysis of AFP and HSA Interactions with PTEN Protein.

    Science.gov (United States)

    Zhu, Mingyue; Lin, Bo; Zhou, Peng; Li, Mengsen

    2015-01-01

    Human cytoplasmic alpha-fetoprotein (AFP) has been classified as a member of the albuminoid gene family. The protein sequence of AFP has significant homology to that of human serum albumin (HSA), but its biological characteristics are vastly different from HSA. The AFP functions as a regulator in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway, but HSA plays a key role as a transport protein. To probe their molecular mechanisms, we have applied colocalization, coimmunoprecipitation (co-IP), and molecular docking approaches to analyze the differences between AFP and HSA. The data from colocalization and co-IP displayed a strong interaction between AFP and PTEN (phosphatase and tensin homolog), demonstrating that AFP did bind to PTEN, but HSA did not. The molecular docking study further showed that the AFP domains I and III could contact with PTEN. In silicon substitutions of AFP binding site residues at position 490M/K and 105L/R corresponding to residues K490 and R105 in HSA resulted in steric clashes with PTEN residues R150 and K46, respectively. These steric clashes may explain the reason why HSA cannot bind to PTEN. Ultimately, the experimental results and the molecular modeling data from the interactions of AFP and HSA with PTEN will help us to identify targets for designing drugs and vaccines against human hepatocellular carcinoma.

  9. Methods to Study PTEN in Mitochondria and Endoplasmic Reticulum.

    Science.gov (United States)

    Missiroli, Sonia; Morganti, Claudia; Giorgi, Carlotta; Pinton, Paolo

    2016-01-01

    Although PTEN has been widely described as a nuclear and cytosolic protein, in the last 2 years, alternative organelles, such as the endoplasmic reticulum (ER), pure mitochondria, and mitochondria-associated membranes (MAMs), have been recognized as pivotal targets of PTEN activity.Here, we describe different methods that have been used to highlight PTEN subcellular localization.First, a protocol to extract nuclear and cytosolic fractions has been described to assess the "canonical" PTEN localization. Moreover, we describe a protocol for mitochondria isolation with proteinase K (PK) to further discriminate whether PTEN associates with the outer mitochondrial membrane (OMM) or resides within the mitochondria. Finally, we focus our attention on a subcellular fractionation protocol of cells that permits the isolation of MAMs containing unique regions of ER membranes attached to the outer mitochondrial membrane (OMM) and mitochondria without contamination from other organelles. In addition to biochemical fractionations, immunostaining can be used to determine the subcellular localization of proteins; thus, a detailed protocol to obtain good immunofluorescence (IF) is described. The employment of these methodological approaches could facilitate the identification of different PTEN localizations in several physiopathological contexts.

  10. 视网膜母细胞瘤组织中 Ki-67、PTEN 表达的变化%Expressions of Ki-67 and PTEN in the Retinoblastoma

    Institute of Scientific and Technical Information of China (English)

    孟海洋

    2016-01-01

    Objective To investigate the expressions of Ki-67 and PTEN in the retinoblastoma and the signifi-cance. Methods Immunohistochemical S-P method was used to detect the expressions of Ki-67 and PTEN in the 97 patients with retinoblastoma and 28 patients with normal retina tissues,their relationship with clinicopathological pa-rameters were analyzed. Results The positive rate of Ki-67 was 66. 0%(64 / 97)in the retinoblastoma,and was 14. 3%(4 / 28)in the normal retina tissues( χ2 = 23. 406,P < 0. 05). The positive rate of Ki-67 was 53. 6%(52 / 97)in the retinoblastoma,and was 92. 9%(26 / 28)in the normal retina tissues(χ2 = 14. 266,P < 0. 05). The expressions of Ki-67 and PTEN in the retinoblastoma were related with cell differentiation degree and clinical stage (P < 0. 05). In the retinoblastoma,the expression of Ki-67 was negatively related with PTEN(r = - 0. 493,P <0. 05). Conclusion Abnormal expressions of Ki-67 and PTEN may be related to the infiltration and development of retinoblastoma.%目的:探讨视网膜母细胞瘤组织中 Ki-67、PTEN 表达的变化及其临床意义。方法采用免疫组化S-P 法检测97例视网膜母细胞瘤和28例正常视网膜组织中 Ki-67、PTEN 的表达水平,并分析两者与视网膜母细胞瘤临床病理参数的关系。结果视网膜母细胞瘤组织中 Ki-67的阳性率为66.0%(64/97),高于正常视网膜组织的14.3%(4/28)(χ2=23.406,P <0.05);视网膜母细胞瘤组织中 PTEN 的阳性率为53.6%(52/97),低于正常视网膜组织的92.9%(26/28)(χ2=14.266,P <0.05)。视网膜母细胞瘤组织中 Ki-67、PTEN 的表达均与患者的分化程度、临床分期有关(P <0.05)。视网膜母细胞瘤组织中 Ki-67、PTEN 的表达呈负相关关系(r =-0.493,P <0.05)。结论 Ki-67、PTEN 的异常表达参与了视网膜母细胞瘤的侵袭和病程进展。

  11. Dietary Regulation of PTEN Signaling and Mammary Tumor Initiating Cells: Implications for Breast Cancer Prevention

    Science.gov (United States)

    2012-07-01

    the end stages of at least two different lines of genetic evolution. J Pathol 2001;194:165–70. [9] Polyak K. Is breast tumor progression really...Gupta GP, Massague J. Cancer metastasis: building a framework. Cell 2006;127: 679–95. [18] Polyak K, Haviv I, Campbell IG. Co-evolution of tumor cells...409–418. 7. Polyak ,K. (2007) Breast cancer: origins and evolution. J. Clin. Invest., 117, 3155–3163. 8. Troisi,R. et al. (2007) Exploring the

  12. Integrin Signaling in Mammary Epithelial Cells and Breast Cancer

    OpenAIRE

    Lambert, Arthur W.; Sait Ozturk; Sam Thiagalingam

    2012-01-01

    Cells sense and respond to the extracellular matrix (ECM) by way of integrin receptors, which facilitate cell adhesion and intracellular signaling. Advances in understanding the mammary epithelial cell hierarchy are converging with new developments that reveal how integrins regulate the normal mammary gland. But in breast cancer, integrin signaling contributes to the development and progression of tumors. This paper highlights recent studies which examine the role of integrin signaling in mam...

  13. Superoxide anion radicals induce IGF-1 resistance through concomitant activation of PTP1B and PTEN.

    Science.gov (United States)

    Singh, Karmveer; Maity, Pallab; Krug, Linda; Meyer, Patrick; Treiber, Nicolai; Lucas, Tanja; Basu, Abhijit; Kochanek, Stefan; Wlaschek, Meinhard; Geiger, Hartmut; Scharffetter-Kochanek, Karin

    2015-01-01

    The evolutionarily conserved IGF-1 signalling pathway is associated with longevity, metabolism, tissue homeostasis, and cancer progression. Its regulation relies on the delicate balance between activating kinases and suppressing phosphatases and is still not very well understood. We report here that IGF-1 signalling in vitro and in a murine ageing model in vivo is suppressed in response to accumulation of superoxide anions (O2∙-) in mitochondria, either by chemical inhibition of complex I or by genetic silencing of O2∙--dismutating mitochondrial Sod2. The O2∙--dependent suppression of IGF-1 signalling resulted in decreased proliferation of murine dermal fibroblasts, affected translation initiation factors and suppressed the expression of α1(I), α1(III), and α2(I) collagen, the hallmarks of skin ageing. Enhanced O2∙- led to activation of the phosphatases PTP1B and PTEN, which via dephosphorylation of the IGF-1 receptor and phosphatidylinositol 3,4,5-triphosphate dampened IGF-1 signalling. Genetic and pharmacologic inhibition of PTP1B and PTEN abrogated O2∙--induced IGF-1 resistance and rescued the ageing skin phenotype. We thus identify previously unreported signature events with O2∙-, PTP1B, and PTEN as promising targets for drug development to prevent IGF-1 resistance-related pathologies.

  14. PTEN基因与皮肤肿瘤%PTEN gene and skin cancer

    Institute of Scientific and Technical Information of China (English)

    郭泽; 周炳荣; 李巍; 骆丹

    2011-01-01

    皮肤肿瘤是一类最常见的肿瘤,在引起皮肤肿瘤发生的诸多原因中,紫外线照射是主要影响因素之一。PTEN是近年来研究较多的一个肿瘤抑制基因,位于染色体10q23,3。目前研究证实,PTEN在多种皮肤肿瘤,如基底细胞癌、鳞状细胞癌、恶性黑素瘤中都起着抑制基因的作用,发现在皮肤肿瘤形成过程中,紫外线照射可引起PTEN失活,对肿瘤的形成可能起着促进的作用。%Skin cancer is one of the most common cancers. Ultraviolet irradiation is the predominant environmental factor causing skin cancer. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor suppressor gene located on chromosome 10 q23,3, which has been frequently studied in recent years. There is evidence that PTEN acts as a tumor suppressor in many skin cancers, such as basal cell carcinoma, squamous cell carcinoma, and melanoma. Ultraviolet irradiation can result in the inactivation of PTEN and in turn promote the development of cancer.

  15. A Novel PTEN/Mutant p53/c-Myc/Bcl-XL Axis Mediates Context-Dependent Oncogenic Effects of PTEN with Implications for Cancer Prognosis and Therapy

    Directory of Open Access Journals (Sweden)

    Xiaoping Huang

    2013-08-01

    Full Text Available Phosphatase and tensin homolog located on chromosome 10 (PTEN is one of the most frequently mutated tumor suppressors in human cancer including in glioblastoma. Here, we show that PTEN exerts unconventional oncogenic effects in glioblastoma through a novel PTEN/mutant p53/c-Myc/Bcl-XL molecular and functional axis. Using a wide array of molecular, genetic, and functional approaches, we demonstrate that PTEN enhances a transcriptional complex containing gain-of-function mutant p53, CBP, and NFY in human glioblastoma cells and tumor tissues. The mutant p53/CBP/NFY complex transcriptionally activates the oncogenes c-Myc and Bcl-XL, leading to increased cell proliferation, survival, invasion, and clonogenicity. Disruption of the mutant p53/c-Myc/Bcl-XL axis or mutant p53/CBP/NFY complex reverses the transcriptional and oncogenic effects of PTEN and unmasks its tumor-suppressive function. Consistent with these data, we find that PTEN expression is associated with worse patient survival than PTEN loss in tumors harboring mutant p53 and that a small molecule modulator of p53 exerts greater antitumor effects in PTEN-expressing cancer cells. Altogether, our study describes a new signaling pathway that mediates context-dependent oncogenic/tumor-suppressive role of PTEN. The data also indicate that the combined mutational status of PTEN and p53 influences cancer prognosis and anticancer therapies that target PTEN and p53.

  16. A new pathway of glucocorticoid action for asthma treatment through the regulation of PTEN expression

    Directory of Open Access Journals (Sweden)

    Chen Qingge

    2011-04-01

    Full Text Available Abstract Background "Phosphatase and tensin homolog deleted on chromosome 10" (PTEN is mostly considered to be a cancer-related gene, and has been suggested to be a new pathway of pathogenesis of asthma. The purpose of this study was to investigate the effects of the glucocorticoid, dexamethasone, on PTEN regulation. Methods OVA-challenged mice were used as an asthma model to investigate the effect of dexamethasone on PTEN regulation. Immunohistochemistry was used to detect expression levels of PTEN protein in lung tissues. The human A549 cell line was used to explore the possible mechanism of action of dexamethasone on human PTEN regulation in vitro. A luciferase reporter construct under the control of PTEN promoter was used to confirm transcriptional regulation in response to dexamethasone. Results PTEN protein was found to be expressed at low levels in lung tissues in asthmatic mice; but the expression was restored after treatment with dexamethasone. In A549 cells, human PTEN was up-regulated by dexamethasone treatment. The promoter-reporter construct confirmed that dexamethasone could regulate human PTEN transcription. Treatment with the histone deacetylase inhibitor, TSA, could increase PTEN expression in A549 cells, while inhibition of histone acetylase (HAT by anacardic acid attenuated dexamethasone-induced PTEN expression. Conclusions Based on the data a new mechanism is proposed where glucocorticoids treat asthma partly through up-regulation of PTEN expression. The in vitro studies also suggest that the PTEN pathway may be involved in human asthma.

  17. The methyltransferase EZH2 is not required for mammary cancer development, although high EZH2 and low H3K27me3 correlate with poor prognosis of ER-positive breast cancers.

    Science.gov (United States)

    Bae, Woo Kyun; Yoo, Kyung Hyun; Lee, Ji Shin; Kim, Young; Chung, Ik-Joo; Park, Min Ho; Yoon, Jung Han; Furth, Priscilla A; Hennighausen, Lothar

    2015-10-01

    Enhancer of zeste homolog 2 (EZH2) catalyzes trimethylation of histone H3 lysine 27 (H3K27me3) and its demethylation is catalyzed by UTX. EZH2 levels are frequently elevated in breast cancer and have been proposed to control gene expression through regulating repressive H3K27me3 marks. However, it is not fully established whether breast cancers with different levels of H3K27me3, EZH2 and UTX exhibit different biological behaviors. Levels of H3K27me3, EZH2 and UTX and their prognostic significance were evaluated in 146 cases of breast cancer. H3K27me3 levels were higher in HER2-negative samples. EZH2 expression was higher in cancers that were LN+, size > 20mm, and with higher tumor grade and stage. Using a Cox regression model, H3K27me3 levels and EZH2 expression were identified as independent prognostic factors for overall survival for all the breast cancers studied as well as the ER-positive subgroup. The combination of low H3K27me3 and high EZH2 expression levels were significantly associated with shorter survival. UTX expression was not significantly associated with prognosis and there were no correlations between H3K27me3 levels and EZH2/UTX expression. To determine if EZH2 is required to establish H3K27me3 marks in mammary cancer, Brca1 and Ezh2 were deleted in mammary stem cells in mice. Brca1-deficient mammary cancers with unaltered H3K27me3 levels developed in the absence of EZH2, demonstrating that EZH2 is not a mandatory H3K27 methyltransferase in mammary neoplasia and providing genetic evidence for biological independence between H3K27me3 and EZH2 in this tissue.

  18. A mammary repopulating cell population characterized in mammary anlagen reveals essential mammary stroma for morphogenesis.

    Science.gov (United States)

    Song, Jiazhe; Xue, Kai; She, Ji; Ding, Fangrong; Li, Song; Shangguan, Rulan; Dai, Yunping; Du, Liying; Li, Ning

    2014-09-10

    The cells with mammary repopulating capability can achieve mammary gland morphogenesis in a suitable cellular microenvironment. Using cell surface markers of CD24, CD29 and CD49f, mouse mammary repopulating unit (MRU) has been identified in adult mammary epithelium and late embryonic mammary bud epithelium. However, embryonic MRU remains to be fully characterized at earlier mammary anlagen stage. Here we isolated discrete populations of E14.5 mouse mammary anlagen cells. Only Lin(-)CD24(med)CD29(+) cell population was predicted as E14.5 MRU by examining their capacities of forming mammosphere and repopulating cleared mammary fat pad in vivo. However, when we characterized gene expressions of this E14.5 cell population by comparing with adult mouse MRU (Lin(-)CD24(+)CD29(hi)), the gene profiling of these two cell populations exhibited great differences. Real-time PCR and immunostaining assays uncovered that E14.5 Lin(-)CD24(med)CD29(+) cell population was a heterogeneous stroma-enriched cell population. Then, limiting dilutions and single-cell assays also confirmed that E14.5 Lin(-)CD24(med)CD29(+) cell population possessed low proportion of stem cells. In summary, heterogeneous Lin(-)CD24(med)CD29(+) cell population exhibited mammary repopulating ability in E14.5 mammary anlagen, implying that only suitable mammary stroma could enable mammary gland morphogenesis, which relied on the interaction between rare stem cells and microenvironment. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. The prostaglandin E2 receptor EP2 is required for cyclooxygenase 2-mediated mammary hyperplasia.

    Science.gov (United States)

    Chang, Sung-Hee; Ai, Youxi; Breyer, Richard M; Lane, Timothy F; Hla, Timothy

    2005-06-01

    Expression of cyclooxygenase 2 (COX-2) in breast cancer correlates with poor prognosis, and COX-2 enzyme inhibitors reduce breast cancer incidence in humans. We recently showed that COX-2 overexpression in the mammary gland of transgenic mice induced mammary cancer. Because prostaglandin E2 (PGE2) is the major eicosanoid and because the EP2 subtype of the PGE2 receptor is highly expressed in the mammary tumors, we tested if this G protein-coupled receptor is required for tumorigenesis. We crossed the MMTV-COX-2 transgenic mice with Ep2-/- mice and studied tumor development in bigenic mice. Lack of EP2 receptor strongly suppressed COX-2-induced effects such as precocious development of the mammary gland in virgins and the development of mammary hyperplasia in multiparous female mice. Interestingly, the expression of amphiregulin, a potent mammary epithelial cell growth factor was down regulated in mammary glands of Ep2-/- mice. Total cyclic AMP (cAMP) levels were reduced in Ep2-/- mammary glands suggesting that PGE2 signaling via the EP2 receptor activates the Gs/cAMP/protein kinase A pathway. In mammary tumor cell lines, expression of the EP2 receptor followed by treatment with CAY10399, an EP2-specific agonist, strongly induced amphiregulin mRNA levels in a protein kinase A-dependent manner. These data suggest that PGE2 signaling via the EP2 receptor in mammary epithelial cells regulate mammary gland hyperplasia by the cAMP-dependent induction of amphiregulin. Inhibition of the EP2 pathway in the mammary gland may be a novel approach in the prevention and/or treatment of mammary cancer.

  20. Neem leaf extract inhibits mammary carcinogenesis by altering cell proliferation, apoptosis, and angiogenesis.

    Science.gov (United States)

    Arumugam, Arunkumar; Agullo, Pamela; Boopalan, Thiyagarajan; Nandy, Sushmita; Lopez, Rebecca; Gutierrez, Christina; Narayan, Mahesh; Rajkumar, Lakshmanaswamy

    2014-01-01

    Plant-based medicines are useful in the treatment of cancer. Many breast cancer patients use complementary and alternative medicine in parallel with conventional treatments. Neem is historically well known in Asia and Africa as a versatile medicinal plant with a wide spectrum of biological activities. The experiments reported herein determined whether the administration of an ethanolic fraction of Neem leaf (EFNL) inhibits progression of chemical carcinogen-induced mammary tumorigenesis in rat models. Seven-week-old female Sprague Dawley rats were given a single intraperitoneal injection of N-methyl-N-nitrosourea (MNU). Upon the appearance of palpable mammary tumors, the rats were divided into vehicle-treated control groups and EFNL-treated groups. Treatment with EFNL inhibited MNU-induced mammary tumor progression. EFNL treatment was also highly effective in reducing mammary tumor burden and in suppressing mammary tumor progression even after the cessation of treatment. Further, we found that EFNL treatment effectively upregulated proapoptotic genes and proteins such as p53, B cell lymphoma-2 protein (Bcl-2)-associated X protein (Bax), Bcl-2-associated death promoter protein (Bad) caspases, phosphatase and tensin homolog gene (PTEN), and c-Jun N-terminal kinase (JNK). In contrast, EFNL treatment caused downregulation of anti-apoptotic (Bcl-2), angiogenic proteins (angiopoietin and vascular endothelial growth factor A [VEGF-A]), cell cycle regulatory proteins (cyclin D1, cyclin-dependent kinase 2 [Cdk2], and Cdk4), and pro-survival signals such as NFκB, mitogen-activated protein kinase 1 (MAPK1). The data obtained in this study demonstrate that EFNL exert a potent anticancer effect against mammary tumorigenesis by altering key signaling pathways.

  1. MiR-20a Induces Cell Radioresistance by Activating the PTEN/PI3K/Akt Signaling Pathway in Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuqin [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Zheng, Lin [Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong Province (China); Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Ding, Yi [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Li, Qi [Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Wang, Rong [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Liu, Tongxin; Sun, Quanquan [Department of Radiation Oncology, Cancer Hospital, Hangzhou, Zhejiang Province (China); Yang, Hua [Department of Radiation Oncology, Nanhai Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Peng, Shunli [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Wang, Wei, E-mail: wangwei9500@hotmail.com [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China); Chen, Longhua, E-mail: chenlhsmu@126.com [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province (China)

    2015-08-01

    Purpose: To investigate the role of miR-20a in hepatocellular carcinoma (HCC) cell radioresistance, which may reveal potential strategies to improve treatment. Methods and Materials: The expression of miR-20a and PTEN were detected in HCC cell lines and paired primary tissues by quantitative real-time polymerase chain reaction. Cell radiation combined with colony formation assays was administrated to discover the effect of miR-20a on radiosensitivity. Bioinformatics prediction and luciferase assay were used to identify the target of miR-20a. The phosphatidylinositol 3-kinase inhibitor LY294002 was used to inhibit phosphorylation of Akt, to verify whether miR-20a affects HCC cell radioresistance through activating the PTEN/PI3K/Akt pathway. Results: MiR-20a levels were increased in HCC cell lines and tissues, whereas PTEN was inversely correlated with it. Overexpression of miR-20a in Bel-7402 and SMMC-7721 cells enhances their resistance to the effect of ionizing radiation, and the inhibition of miR-20a in HCCLM3 and QGY-7701 cells sensitizes them to it. PTEN was identified as a direct functional target of miR-20a for the induction of radioresistance. Overexpression of miR-20a activated the PTEN/PI3K/Akt signaling pathway. Additionally, the kinase inhibitor LY294002 could reverse the effect of miR-20a–induced radioresistance. Conclusion: MiR-20a induces HCC cell radioresistance by activating the PTEN/PI3K/Akt pathway, which suggests that miR-20a/PTEN/PI3K/Akt might represent a target of investigation for developing effective therapeutic strategies against HCC.

  2. Sequencing the transcriptome of milk production: milk trumps mammary tissue

    OpenAIRE

    Lemay, Danielle G; Hovey, Russell C.; Hartono, Stella R; Hinde, Katie; Smilowitz, Jennifer T.; Ventimiglia, Frank; Schmidt, Kimberli A; Lee, Joyce WS; Islas-Trejo, Alma; Silva, Pedro Ivo; Korf, Ian; Medrano, Juan F.; Barry, Peter A.; German, J. Bruce

    2013-01-01

    Abstract Background Studies of normal human mammary gland development and function have mostly relied on cell culture, limited surgical specimens, and rodent models. Although RNA extracted from human milk has been used to assay the mammary transcriptome non-invasively, this assay has not been adequately validated in primates. Thus, the objectives of the current study were to assess the suitability of lactating rhesus macaques as a model for lactating ...

  3. MUC1 positive, Kras and Pten driven mouse gynecologic tumors replicate human tumors and vary in survival and nuclear grade based on anatomical location.

    Science.gov (United States)

    Tirodkar, Tejas S; Budiu, Raluca A; Elishaev, Esther; Zhang, Lixin; Mony, Jyothi T; Brozick, Joan; Edwards, Robert P; Vlad, Anda M

    2014-01-01

    Activating mutations of Kras oncogene and deletions of Pten tumor suppressor gene play important roles in cancers of the female genital tract. We developed here new preclinical models for gynecologic cancers, using conditional (Cre-loxP) mice with floxed genetic alterations in Kras and Pten. The triple transgenic mice, briefly called MUC1KrasPten, express human MUC1 antigen as self and carry a silent oncogenic KrasG12D and Pten deletion mutation. Injection of Cre-encoding adenovirus (AdCre) in the ovarian bursa, oviduct or uterus activates the floxed mutations and initiates ovarian, oviductal, and endometrial cancer, respectively. Anatomical site-specific Cre-loxP recombination throughout the genital tract of MUC1KrasPten mice leads to MUC1 positive genital tract tumors, and the development of these tumors is influenced by the anatomical environment. Endometrioid histology was consistently displayed in all tumors of the murine genital tract (ovaries, oviducts, and uterus). Tumors showed increased expression of MUC1 glycoprotein and triggered de novo antibodies in tumor bearing hosts, mimicking the immunobiology seen in patients. In contrast to the ovarian and endometrial tumors, oviductal tumors showed higher nuclear grade. Survival for oviduct tumors was significantly lower than for endometrial tumors (p = 0.0015), yet similar to survival for ovarian cancer. Oviducts seem to favor the development of high grade tumors, providing preclinical evidence in support of the postulated role of fallopian tubes as the originating site for high grade human ovarian tumors.

  4. Reduced Expression of PTEN Protein and Its Prognostic Significance in the Gastrointestinal Stromal Tumor

    Institute of Scientific and Technical Information of China (English)

    张永红; 于冬冬; 李小兰; 胡俊波; 龚建平

    2010-01-01

    Little is reported about the role of PTEN gene in the progression and prognosis of GISTs.This study examined the clinical implications of the tumor suppressor gene PTEN as a prognostic factor in the GISTs.Immunohistological staining and immunoblotting were employed to examine the PTEN protein expression,and its association with clinical measures.Clinicopathological features were reviewed by a retrospective examination of medical records.Reduced PTEN expression was significantly associated with tumor diamete...

  5. Phosphorylation of PTEN at STT motif is associated with DNA damage response.

    Science.gov (United States)

    Misra, Sandip; Mukherjee, Ananda; Karmakar, Parimal

    2014-12-01

    Phosphatase and tensin homolog deleted on chromosome Ten (PTEN), a tumor suppressor protein participates in multiple cellular activities including DNA repair. In this work we found a relationship between phosphorylation of carboxy (C)-terminal STT motif of PTEN and DNA damage response. Ectopic expression of C-terminal phospho-mutants of PTEN, in PTEN deficient human glioblastoma cells, U87MG, resulted in reduced viability and DNA repair after etoposide induced DNA damage compared to cells expressing wild type PTEN. Also, after etoposide treatment phosphorylation of PTEN increased at C-terminal serine 380 and threonine 382/383 residues in PTEN positive HEK293T cells and wild type PTEN transfected U87MG cells. One-step further, DNA damage induced phosphorylation of PTEN was confirmed by immunoprecipitation of total PTEN from cellular extract followed by immunobloting with phospho-specific PTEN antibodies. Additionally, phospho-PTEN translocated to nucleus after etoposide treatment as revealed by indirect immunolabeling. Further, phosphorylation dependent nuclear foci formation of PTEN was observed after ionizing radiation or etoposide treatment which colocalized with γH2AX. Additionally, etoposide induced γH2AX, Mre11 and Ku70 foci persisted for a longer period of times in U87MG cells after ectopic expression of PTEN C-terminal phospho-mutant constructs compared to wild type PTEN expressing cells. Thus, our findings strongly suggest that DNA damage induced phosphorylation of C-terminal STT motif of PTEN is necessary for DNA repair. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Deregulated ephrin-B2 expression in the mammary gland interferes with the development of both the glandular epithelium and vasculature and promotes metastasis formation.

    Science.gov (United States)

    Haldimann, Mirjam; Custer, Domenica; Munarini, Nadia; Stirnimann, Christoph; Zürcher, Gisela; Rohrbach, Valeria; Djonov, Valentin; Ziemiecki, Andrew; Andres, Anne-Catherine

    2009-09-01

    Eph receptor tyrosine kinases and their membrane-bound ephrin ligands play key roles during morphogenesis and adult tissue homeostasis. Receptor-ligand interactions result in forward and reverse signalling from the receptor and ligand respectively. To delineate the role(s) of forward and reverse signalling in mammary gland biology we have established transgenic mice exhibiting mammary epithelial-specific overexpression of either the native ephrin-B2 or a dominant negative ephrin-B2 mutant incapable of reverse signalling. During pregnancy and lactation overexpression of the native ephrin-B2 resulted in precocious differentiation, whereas overexpression of mutated ephrin-B2 caused delayed epithelial differentiation and in disturbed tissue architecture. Both transgenes affected also mammary vascularisation. Whereas ephrin-B2 induced superfluous but organised capillaries, mutant ephrin-B2 overexpression resulted in an irregular vasculature with blind-ending capillaries. Mammary tumours were not observed in either transgenic line, however, the crossing with NeuT transgenic animals revealed that mutated ephrin-B2 expression significantly accelerated tumour growth and imposed a metastatic phenotype.

  7. Suppression of gastric cancer growth by adenovirus-mediated transfer of the PTEN gene

    Institute of Scientific and Technical Information of China (English)

    Ying Hang; Yong-Chen Zheng; Yan Cao; Qing-Shan Li; Yu-Jie Sui

    2005-01-01

    AIM: To investigate the tumor-suppressive effect of the phosphatase and tensin homologue deleted from chromosome (PTEN) in human gastric cancer cells th atwere wild type for PTEN.METHODS: Adenoviruses expressing PTEN or luciferase as a control were introduced into gastric cancer cells.The effect of exogenous PTEN gene on the growth and apoptosis of gastric cancer cells that are wtPTEN were examined in vitro and in vivo.RESULTS: Adenovirus-mediated transfer of PTEN (AdPTEN) suppressed cell growth and induced apoptosis significantly in gastric cancer cells (MGC-803, SGC-7901)carrying wtPTEN in comparison with that in normal gastric epithelial cells (GES-1) carrying wtPTEN. This suppression was induced through downregulation of the Akt/PKB pathway, dephosphorylation of focal adhesion kinase and mitogen-activated protein kinase and cell-cycle arrest at the G2/M phase but not at the G1 phase. Furthermore,treatment of human gastric tumor xenografts (MGC-803,SGC-7901) with Ad-PTEN resulted in a significant (P<0.01)suppression of tumor growth.CONCLUSION: These results indicate a significant tumorsuppressive effect of Ad-PTEN against human gastric cancer cells. Thus, Ad-PTEN may be used as a potential therapeutic strategy for treatment of gastric cancers.

  8. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Zhen [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Gan, Ye-Hua, E-mail: kqyehuagan@bjmu.edu.cn [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China)

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

  9. Dietary tocopherols inhibit cell proliferation, regulate expression of ERα, PPARγ, and Nrf2, and decrease serum inflammatory markers during the development of mammary hyperplasia.

    Science.gov (United States)

    Smolarek, Amanda K; So, Jae Young; Thomas, Paul E; Lee, Hong Jin; Paul, Shiby; Dombrowski, Anne; Wang, Chung-Xiou; Saw, Constance Lay-Lay; Khor, Tin Oo; Kong, Ah-Ng Tony; Reuhl, Kenneth; Lee, Mao-Jung; Yang, Chung S; Suh, Nanjoo

    2013-07-01

    Previous clinical and epidemiological studies of vitamin E have used primarily α-tocopherol for the prevention of cancer. However, γ-tocopherol has demonstrated greater anti-inflammatory and anti-tumor activity than α-tocopherol in several animal models of cancer. This study assessed the potential chemopreventive activities of a tocopherol mixture containing 58% γ-tocopherol (γ-TmT) in an established rodent model of mammary carcinogenesis. Female ACI rats were utilized due to their sensitivity to 17β-estradiol (E2 ) to induce mammary hyperplasia and neoplasia. The rats were implanted subcutaneously with sustained release E2 pellets and given dietary 0.3% or 0.5% γ-TmT for 2 or 10 wk. Serum E2 levels were significantly reduced by the treatment with 0.5% γ-TmT. Serum levels of inflammatory markers, prostaglandin E2 and 8-isoprostane, were suppressed by γ-TmT treatment. Histology of mammary glands showed evidence of epithelial hyperplasia in E2 -treated rats. Immunohistochemical analysis of the mammary glands revealed a decrease in proliferating cell nuclear antigen (PCNA), cyclooxygenase-2 (COX-2), and estrogen receptor α (ERα), while there was an increase in cleaved-caspase 3, peroxisome proliferator-activated receptor γ (PPARγ), and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in γ-TmT-treated rats. In addition, treatment with γ-TmT resulted in a decrease in the expression of ERα mRNA, whereas mRNA levels of ERβ and PPARγ were increased. In conclusion, γ-TmT was shown to suppress inflammatory markers, inhibit E2 -induced cell proliferation, and upregulate PPARγ and Nrf2 expression in mammary hyperplasia, suggesting that γ-TmT may be a promising agent for human breast cancer prevention.

  10. Oxidized LDL triggers pro-oncogenic signaling in human breast mammary epithelial cells partly via stimulation of MiR-21.

    Directory of Open Access Journals (Sweden)

    Magomed Khaidakov

    Full Text Available Dyslipidemia and obesity are primary risk factors for the development of atherosclerosis and are also epidemiologically linked to increased susceptibility to a variety of cancers including breast cancer. One of the prominent features of dyslipidemia is enhanced production of oxidized LDL (ox-LDL, which has been shown to be implicated in key steps of atherogenesis including inflammatory signaling and proliferation of vascular cells. In this study we analyzed the effects of ox-LDL in human mammary epithelial cells (MCF10A. MCF10A cells avidly internalized dil-ox-LDL and exhibited increased proliferative response to ox-LDL within the range of 1-50 µg/ml in a dose-dependent manner. Treatment of cells with 20 µg/ml ox-LDL for 2 and 12 hours was associated with upregulation of LOX-1 and CD36 scavenger receptors while MSR1 and CXLC16 receptors did not change. Ox-LDL-treated cells displayed significant upregulation of NADPH oxidases (subunits P22(phox and P47(phox, lipoxygenases-12 and -15, and cytoplasmic, but not mitochondrial, SOD. Ox-LDL also triggered phosphorylation of IκBα coupled with nuclear translocation of NF-κB and stimulated p44/42 MAPK, PI3K and Akt while intracellular PTEN (PI3K/Akt pathway inhibitor and target of miR-21 declined. Quantitative PCR revealed increased expression of hsa-miR-21 in ox-LDL treated cells coupled with inhibition of miR-21 target genes. Further, transfection of MCF10A cells with miR-21 inhibitor prevented ox-LDL mediated stimulation of PI3K and Akt. We conclude that, similarly to vascular cells, mammary epithelial cells respond to ox-LDL by upregulation of proliferative and pro-inflammatory signaling. We also report for the first time that part of ox-LDL triggered reactions in MCF10A cells is mediated by oncogenic hsa-miR-21 through inhibition of its target gene PTEN and consequent activation of PI3K/Akt pathway.

  11. Oxidized LDL triggers pro-oncogenic signaling in human breast mammary epithelial cells partly via stimulation of MiR-21.

    Science.gov (United States)

    Khaidakov, Magomed; Mehta, Jawahar L

    2012-01-01

    Dyslipidemia and obesity are primary risk factors for the development of atherosclerosis and are also epidemiologically linked to increased susceptibility to a variety of cancers including breast cancer. One of the prominent features of dyslipidemia is enhanced production of oxidized LDL (ox-LDL), which has been shown to be implicated in key steps of atherogenesis including inflammatory signaling and proliferation of vascular cells. In this study we analyzed the effects of ox-LDL in human mammary epithelial cells (MCF10A). MCF10A cells avidly internalized dil-ox-LDL and exhibited increased proliferative response to ox-LDL within the range of 1-50 µg/ml in a dose-dependent manner. Treatment of cells with 20 µg/ml ox-LDL for 2 and 12 hours was associated with upregulation of LOX-1 and CD36 scavenger receptors while MSR1 and CXLC16 receptors did not change. Ox-LDL-treated cells displayed significant upregulation of NADPH oxidases (subunits P22(phox) and P47(phox)), lipoxygenases-12 and -15, and cytoplasmic, but not mitochondrial, SOD. Ox-LDL also triggered phosphorylation of IκBα coupled with nuclear translocation of NF-κB and stimulated p44/42 MAPK, PI3K and Akt while intracellular PTEN (PI3K/Akt pathway inhibitor and target of miR-21) declined. Quantitative PCR revealed increased expression of hsa-miR-21 in ox-LDL treated cells coupled with inhibition of miR-21 target genes. Further, transfection of MCF10A cells with miR-21 inhibitor prevented ox-LDL mediated stimulation of PI3K and Akt. We conclude that, similarly to vascular cells, mammary epithelial cells respond to ox-LDL by upregulation of proliferative and pro-inflammatory signaling. We also report for the first time that part of ox-LDL triggered reactions in MCF10A cells is mediated by oncogenic hsa-miR-21 through inhibition of its target gene PTEN and consequent activation of PI3K/Akt pathway.

  12. Identification of Cytoplasmic Proteins Interacting with the Mammary Cell Transforming Domain of Ese-1

    Science.gov (United States)

    2009-04-01

    2005). Additionally, 3’ polymorphisms of Ets1 are associated with different clinical manifestations of systemic lupus erythematosus (Sullivan et al...of mammary epithelial cell growth [24]. In postnatal mammary glands, ETS factors have been shown to have key roles in pregnancy -induced, PRL- mediated...mammary gland lobuloalveolar development and milk production and in breast tumorigenesis. In the early phase of pregnancy , a proliferative phase of

  13. Modulation of T-Cell Activation in an Experimental Model of Mammary Carcinoma.

    Science.gov (United States)

    1998-07-01

    with MNU following pituitary isografts that, if left untreated, would go on to develop mammary Hurwitz---5 tumors at a high incidence (~70% at 10... isograft under the kidney capsule and 1 week later, given a single i.p. dose of MNU [as described in (19)]. Mice were monitored weekly for mammary tumors...system, mice are implanted with a pituitary isograft to induce proliferation of the mammary tissue and subsequently mutagenized with MNU (50 mg/kg

  14. Canonical Wnt Signaling as a Specific Marker of Normal and Tumorigenic Mammary Stem Cells

    Science.gov (United States)

    2013-02-01

    mammary epithelium impacts glandular development . We found ductal abnormali ties; however, the phenotype was not as severe as expected. Approximately...In previous reports we have clearly showed that cells w ith activated canonical Wnt signaling are present within the mammary epithelium starting at...Wnt1 transgenic cells. We generated a mouse line in which ~-catenin is conditionally deleted in the mammary epithelium of MMTV-Wnt1 transgenic

  15. Loss of sfrp1 promotes ductal branching in the murine mammary gland

    OpenAIRE

    Gauger Kelly J; Shimono Akihiko; Crisi Giovanna M; Schneider Sallie

    2012-01-01

    Abstract Background Secreted frizzled-related proteins (SFRPs) are a family of proteins that block the Wnt signaling pathway and loss of SFRP1 expression is found in breast cancer along with a multitude of other human cancers. Activated Wnt signaling leads to inappropriate mammary gland development and mammary tumorigenesis in mice. When SFRP1 is knocked down in immortalized non-malignant mammary epithelial cells, the cells exhibit a malignant phenotype which resembles the characteristics obs...

  16. PTEN overexpression improves cisplatin-resistance of human ovarian cancer cells through upregulating KRT10 expression

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huijuan; Wang, Ke; Liu, Wenxin; Hao, Quan, E-mail: quan_haotj@126.com

    2014-02-07

    Highlights: • Overexpression of PTEN enhanced the sensitivity of C13K cells to cisplatin. • KRT10 is a downstream molecule of PTEN involved in the resistance-reversing effect. • Overexpression of KRT10 enhanced the chemosensitivity of C13K cells to cisplatin. - Abstract: Multi-drug resistance (MDR) is a common cause of the failure of chemotherapy in ovarian cancer. PTEN, a tumor suppressor gene, has been demonstrated to be able to reverse cisplatin-resistance in ovarian cancer cell line C13K. However, the downstream molecules of PTEN involved in the resistance-reversing effect have not been completely clarified. Therefore, we screened the downstream molecules of PTEN and studied their interactions in C13K ovarian cancer cells using a 3D culture model. Firstly, we constructed an ovarian cancer cell line stably expressing PTEN, C13K/PTEN. MTT assay showed that overexpression of PTEN enhanced the sensitivity of C13K cells to cisplatin, but not to paclitaxel. Then we examined the differently expressed proteins that interacted with PTEN in C13K/PTEN cells with or without cisplatin treatment by co-immunoprecipitation. KRT10 was identified as a differently expressed protein in cisplatin-treated C13K/PTEN cells. Further study confirmed that cisplatin could induce upregulation of KRT10 mRNA and protein in C13K/PTEN cells and there was a directly interaction between KRT10 and PTEN. Forced expression of KRT10 in C13K cells also enhanced cisplatin-induced proliferation inhibition and apoptosis of C13K cells. In addition, KRT10 siRNA blocked cisplatin-induced proliferation inhibition of C13K/PTEN cells. In conclusion, our data demonstrate that KRT10 is a downstream molecule of PTEN which improves cisplatin-resistance of ovarian cancer and forced KRT10 overexpression may also act as a therapeutic method for overcoming MDR in ovarian cancer.

  17. Gene expression analysis of PTEN positive glioblastoma stem cells identifies DUB3 and Wee1 modulation in a cell differentiation model.

    Directory of Open Access Journals (Sweden)

    Stefano Forte

    Full Text Available The term astrocytoma defines a quite heterogeneous group of neoplastic diseases that collectively represent the most frequent brain tumors in humans. Among them, glioblastoma multiforme represents the most malignant form and its associated prognosis is one of the poorest among tumors of the central nervous system. It has been demonstrated that a small population of tumor cells, isolated from the brain neoplastic tissue, can reproduce the parental tumor when transplanted in immunodeficient mouse. These tumor initiating cells are supposed to be involved in cancer development and progression and possess stem cell-like features; like their normal counterpart, these cells remain quiescent until they are committed to differentiation. Many studies have shown that the role of the tumor suppressor protein PTEN in cell cycle progression is fundamental for tumor dynamics: in low grade gliomas, PTEN contributes to maintain cells in G1 while the loss of its activity is frequently observed in high grade gliomas. The mechanisms underlying the above described PTEN activity have been studied in many tumors, but those involved in the maintenance of tumor initiating cells quiescence remain to be investigated in more detail. The aim of the present study is to shed light on the role of PTEN pathway on cell cycle regulation in Glioblastoma stem cells, through a cell differentiation model. Our results suggest the existence of a molecular mechanism, that involves DUB3 and WEE1 gene products in the regulation of Cdc25a, as functional effector of the PTEN/Akt pathway.

  18. A MOUSE MODEL OF MAMMARY HYPERPLASIA INDUCED BY ORAL HORMONE ADMINISTRATION.

    Science.gov (United States)

    Sun, Li; Guo, Dong-Hui; Liu, Fei; Liu, Qian; Jiang, Ning; Sun, Yun-Feng; Cai, Li-Ping; Zheng, Hong-Xin

    2017-01-01

    Mammary hyperplasia is one of the most common benign breast disorders. Although traditional Chinese medicine has a vast experience in the treatment of mammary hyperplasia, it is not accepted widely due to its unclear mechanism. To address the mechanism, we developed a mouse model of mammary hyperplasia. We gave mice estradiol valerate tablets and progesterone capsules sequentially for one month by intragastric administration. Mice treated by this method had a series of pathological changes which are similar to those detected in women with mammary hyperplasia, including ectopic level of estradiol and progesterone in serum, hyperplasia of mammary glands and increased expression of ERα and PR. This model will facilitate the mechanical study of traditional medicine on mammary hyperplasia.

  19. [Inhibitory effects of tumor suppressor gene PTEN on proliferation and metastasis of breast cancer ZR-75-1 cells].

    Science.gov (United States)

    Lin, Guan-Ping; Li, Xiang-Yong; Huang, Jin-Wen; Xiong, Liang; Zhou, Ke-Yuan

    2007-10-01

    Tumor suppressor gene PTEN could not only inhibit the proliferation of cancer cells, but also inhibit their metastasis. However, the mechanism is still unclear. This study was to investigate the effects of PTEN gene on the proliferation and metastasis of human breast cancer ZR-75-1 cells, and explore the mechanisms. Wild-type PTEN (wt-PTEN) plasmid and phosphatase-defective PTEN (G129R-PTEN) plasmid were transfected into ZR-75-1 cells by liposome, respectively. Cell proliferation was detected by MTT assay. Transfected cells were selected by puromycin. The expression of PTEN protein was detected by Western blot. Cell adhesion and invasion were tested by adhesion test and invasion test. The proliferation inhibition rate was significantly higher in wt-PTEN-transfected ZR-75-1 cells than in untransfected cells and G129R-PTEN-transfected cells (42.7% vs. 0% and 2.7%, P0.05). The proliferation inhibition of ZR-75-1 cells was enhanced along with the increase of culture time and concentration of wt-PTEN. wt-PTEN also induced cell apoptosis. PTEN protein was expressed efficiently in the cells transfected with either wt-PTEN or G129R-PTEN. The inhibition rates of adhesion and invasion were significantly higher in wt-PTEN-transfected cells than in G129R-PTEN-transfected cells (65.7% vs. 8.8%, 70.4% vs. 6.9%, PZR-75-1 cells.

  20. Molecular Mechanism of Nkx3.1 Deregulation and its Function in Murine Pten Prostate Cancer Model

    Science.gov (United States)

    2006-09-01

    hybridization , post hybridization , and analyses following standard laboratory procedure. The probe cocktail contained 20 differentially labeled chromosome...contain near tetraploid chromosome number, with 65-84 chromosomes in PTEN-P2 and 76-80 chromosomes in PTEN-CaP2; PTEN- P8 and PTEN-CaP8 have near 6N

  1. Perspective on calf and mammary gland development through changes in the bovine milk proteome over a complete lactation

    NARCIS (Netherlands)

    Zhang, L.; Boeren, J.A.; Hageman, J.A.; Hooijdonk, van A.C.M.; Vervoort, J.J.M.; Hettinga, K.A.

    2015-01-01

    Milk contains all the nutrients for the growth and development of the neonate. However, milk composition is not constant during lactation. To study the changes of the milk proteome over lactation, filter-aided sample preparation combined with dimethyl labeling followed by liquid chromatography tande

  2. Immunohistochemical characterization of mammary squamous cell carcinoma of the dog.

    Science.gov (United States)

    Sassi, Francesco; Sarli, Giuseppe; Brunetti, Barbara; Morandi, Federico; Benazzi, Cinzia

    2008-11-01

    Squamous cell carcinoma of the mammary gland is rare in both veterinary and human medicine. Whereas human metaplastic and squamous variants are known, the objectives of the current study were to ascertain the presence of such entities in canine mammary tumors and to distinguish them from other (epidermal, sweat gland) squamous tumors that may develop in the same area. A panel of antibodies (anti-cytokeratin [CK] 19, CK 14, CK 5/6, pancytokeratin, and vimentin) was used on 18 mammary gland malignancies with squamous features and 16 malignant skin tumors (11 squamous cell carcinomas of the skin and 5 sweat glands). Fifteen of the 18 mammary carcinomas were classified as metaplastic carcinomas, and the remaining 3 were classified as squamous cell carcinomas. The 2 most useful markers to establish the histogenesis of mammary tumors were pancytokeratin and CK 19. All other antibodies were equally expressed (CK 14 and 5/6) in all histotypes. The antibody panel discriminated primary epidermal squamous tumors (pancytokeratin positive and CK 19 negative) from gland-derived squamous neoplasms (pancytokeratin positive and CK 19 positive) but failed to distinguish primary mammary tumors from other squamous tumors of glandular origin.

  3. Human Internal Mammary Artery (IMA) Transplantation and Stenting: A Human Model to Study the Development of In-Stent Restenosis

    Science.gov (United States)

    Hua, Xiaoqin; Deuse, Tobias; Michelakis, Evangelos D.; Haromy, Alois; Tsao, Phil S.; Maegdefessel, Lars; Erben, Reinhold G.; Bergow, Claudia; Behnisch, Boris B.; Reichenspurner, Hermann; Robbins, Robert C.; Schrepfer, Sonja

    2012-01-01

    Preclinical in vivo research models to investigate pathobiological and pathophysiological processes in the development of intimal hyperplasia after vessel stenting are crucial for translational approaches1,2. The commonly used animal models include mice, rats, rabbits, and pigs3-5. However, the translation of these models into clinical settings remains difficult, since those biological processes are already studied in animal vessels but never performed before in human research models6,7. In this video we demonstrate a new humanized model to overcome this translational gap. The shown procedure is reproducible, easy, and fast to perform and is suitable to study the development of intimal hyperplasia and the applicability of diverse stents. This video shows how to perform the stent technique in human vessels followed by transplantation into immunodeficient rats, and identifies the origin of proliferating cells as human. PMID:22617624

  4. Mammary ductoscopy: past, present, and future.

    Science.gov (United States)

    Pereira, Bernadette; Mokbel, Kefah

    2005-04-01

    Mammary ductoscopy (MD) allows direct visual access to the mammary ducts, using fiberoptic microendoscopes inserted through the ductal opening onto the nipple surface. Therefore it has a potential role in the diagnosis and treatment of intraductal breast disease. This article describes the anatomy of the mammary ductal system, the early beginnings of MD, its ongoing evolution, and the need for further development for its future usage in increasing clinical indications. MD is a useful diagnostic adjunct in patients with pathological nipple discharge (PND) and can guide duct excision surgery. However, its potential use in the early detection of breast cancer, in guiding breast-conserving surgery (BCS) for cancer, and in the therapeutic ablation of intraductal disease, as well as in guiding risk-reducing strategies among high-risk women, requires further research and evaluation. The development of a biopsy kit that obtains adequate microbiopsy samples for histological diagnosis under direct visualization will enhance the use of this technique by breast surgeons and radiologists. Future developments also include combining MD with molecular diagnostic markers and optical biopsy systems for the diagnosis of premalignant and early malignant disease, and combining MD with radiofrequency for curative ablation of intraductal lesions.

  5. Mammary ductoscopy: current issues and perspectives.

    Science.gov (United States)

    Uchida, Ken; Fukushima, Hisaki; Toriumi, Yasuo; Kawase, Kazumi; Tabei, Isao; Yamashita, Akinori; Nogi, Hiroko

    2009-01-01

    Until recently, the mammary duct had not been directly observed in vivo. Starting with the success of Teboul et al., studies of mammary ductoscopy (MD) for nipple discharge have been performed in Japan and other East Asian countries. Ductal lavage screening trials for breast cancer started in the 2000s. Concurrently, the number of English-language articles about MD increased. Sixty-nine English-language and 74 Japanese-language papers published in the last 19 years were reviewed. Important reports and studies were analyzed. MD has undergone significant technological development, and studies of MD have taken place in many countries. As a result, endoscopic images of the mammary duct have developed, and the endoscopic diagnosis for nipple discharge has become possible. MD-guided biopsy and surgery have been studied. Findings of MD are useful for diagnosing intraductal lesions with nipple discharge. As a result, MD has reduced the number and extent of microdochectomies. MD is also helpful in guiding breast-conserving surgery. Many pioneers have tried direct biopsy or interventions under MD, but further developments are necessary for its practical use.

  6. Mammary Gland Tumor Development in Transgenic Mice Overexpressing Different Isoforms of the CDP/Cux Transcription Factor

    Science.gov (United States)

    2009-03-01

    overexpression of p75 CUX1 results in the development of myeloproliferative disease-like myeloid leukemia in mice (8). My project consisted in analyzing the... pregnancy and lactation (Appendix 1B and C). Note that immunochemical staining with the CUX1 antibodies was not sensitive enough to detect...gland was analyzed by reverse-transcription polymerase-chain-reaction (RT-PCR) at 5 weeks (virgin), 3 months (virgin), 7.5 day pregnancy (P), 6 day

  7. Slugging their way to immortality: driving mammary epithelial cells into a stem cell-like state.

    Science.gov (United States)

    Soady, Kelly; Smalley, Matthew J

    2012-09-10

    Delineating the molecular factors that define and maintain the mammary stem cell state is vital for understanding normal development and tumourigenesis. A recent study by Guo and colleagues identifies two master transcriptional regulators of mammary stem cells, Slug and Sox9, ectopic expression of which confers stem cell attributes on differentiated mammary epithelial cells. Slug and Sox9 expression was also shown to determine in vivo metastatic potential of human breast cancer cell lines. Understanding these factors in the context of normal lineage differentiation is an important step toward elucidating the mammary epithelial cell hierarchy and the origins of cancer stem cells.

  8. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    Directory of Open Access Journals (Sweden)

    Cotarla Ion

    2008-01-01

    Full Text Available Abstract Background Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. Methods We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. Results In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. Conclusion In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary.

  9. ΔNp63 promotes stem cell activity in mammary gland development and basal-like breast cancer by enhancing Fzd7 expression and Wnt signalling.

    Science.gov (United States)

    Chakrabarti, Rumela; Wei, Yong; Hwang, Julie; Hang, Xiang; Andres Blanco, Mario; Choudhury, Abrar; Tiede, Benjamin; Romano, Rose-Anne; DeCoste, Christina; Mercatali, Laura; Ibrahim, Toni; Amadori, Dino; Kannan, Nagarajan; Eaves, Connie J; Sinha, Satrajit; Kang, Yibin

    2014-10-01

    Emerging evidence suggests that cancer is populated and maintained by tumour-initiating cells (TICs) with stem-like properties similar to those of adult tissue stem cells. Despite recent advances, the molecular regulatory mechanisms that may be shared between normal and malignant stem cells remain poorly understood. Here we show that the ΔNp63 isoform of the Trp63 transcription factor promotes normal mammary stem cell (MaSC) activity by increasing the expression of the Wnt receptor Fzd7, thereby enhancing Wnt signalling. Importantly, Fzd7-dependent enhancement of Wnt signalling by ΔNp63 also governs tumour-initiating activity of the basal subtype of breast cancer. These findings establish ΔNp63 as a key regulator of stem cells in both normal and malignant mammary tissues and provide direct evidence that breast cancer TICs and normal MaSCs share common regulatory mechanisms.

  10. Strain-Specific Spontaneous and NNK-Mediated Tumorigenesis in Pten+/− Mice

    Directory of Open Access Journals (Sweden)

    Mary Christine Hollander

    2008-08-01

    Full Text Available Pten is a negative regulator of the Akt pathway, and its inactivation is believed to be an etiological factor in many tumor types. Pten+/- mice are susceptible to a variety of spontaneous tumor types, depending on strain background. Pten+/- mice, in lung tumor-sensitive and -resistant background strains, were treated with a tobacco carcinogen, 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK, to determine whether allelic Pten deletion can cooperate with NNK in carcinogenesis in lung or other tissues. In lung tumor-resistant C57BL/6 Pten+/- or +/+ mice, NNK treatment did not lead to any lung tumors and did not increase the incidence or severity of tumors previously reported for this strain. In contrast, in a lung tumor-susceptible pseudo-A/J strain, there was a dose-dependent increase in lung tumor size in Pten+/- compared with +/+ mice, although there was no increase in multiplicity. No other tumor types were observed in pseudo-A/J Pten+/- mice regardless of NNK treatment. Lung tumors from these Pten+/- mice had K-ras mutations, retained Pten expression and had similar Akt pathway activation as lung tumors from +/+ mice. Therefore, deletion of a single copy of Pten does not substantially add to the lung tumor phenotype conferred by mutation of K-ras by NNK, and there is likely no selective advantage for loss of the second Pten allele in lung tumor initiation.

  11. Nuclear trafficking of Pten after brain injury leads to neuron survival not death.

    Science.gov (United States)

    Goh, Choo-Peng; Putz, Ulrich; Howitt, Jason; Low, Ley-Hian; Gunnersen, Jenny; Bye, Nicole; Morganti-Kossmann, Cristina; Tan, Seong-Seng

    2014-02-01

    There is controversy whether accumulation of the tumor suppressor PTEN protein in the cell nucleus under stress conditions such as trauma and stroke causes cell death. A number of in vitro studies have reported enhanced apoptosis in neurons possessing nuclear PTEN, with the interpretation that its nuclear phosphatase activity leads to reduction of the survival protein phospho-Akt. However, there have been no in vivo studies to show that nuclear PTEN in neurons under stress is detrimental. Using a mouse model of injury, we demonstrate here that brain trauma altered the nucleo-cytoplasmic distribution of Pten, resulting in increased nuclear Pten but only in surviving neurons near the lesion. This event was driven by Ndfip1, an adaptor and activator of protein ubiquitination by Nedd4 E3 ligases. Neurons next to the lesion with nuclear PTEN were invariably negative for TUNEL, a marker for cell death. These neurons also showed increased Ndfip1 which we previously showed to be associated with neuron survival. Biochemical assays revealed that overall levels of Pten in the affected cortex were unchanged after trauma, suggesting that Pten abundance globally had not increased but rather Pten subcellular location in affected neurons had changed. Following experimental injury, the number of neurons with nuclear Pten was reduced in heterozygous mice (Ndfip1(+/-)) although lesion volumes were increased. We conclude that nuclear trafficking of Pten following injury leads to neuron survival not death.

  12. Mammary tuberculosis: percutaneous treatment of a mammary tuberculous abscess

    Energy Technology Data Exchange (ETDEWEB)

    Romero, C.; Carreira, C.; Cereceda, C.; Pinto, J. [Servicio de Radiologia, Hospital Virgen de la Salud, Toledo (Spain); Lopez, R.; Bolanos, F. [Servicio de Cirugia, Hospital Virgen de la Salud, Toledo (Spain)

    2000-03-01

    It is currently very rare to find mammary involvement in cases of tuberculosis, in either primary or secondary form. Diagnosis is classically clinical and microbiological, and the basic techniques used in imaging diagnosis are mammography and ultrasound. Computed tomography may define the involvement of the thoracic wall in those cases which present as mammary masses adhering to deep levels, and is also able to evaluate accompanying pulmonary disease, if it is present. Traditionally, treatment has consisted of quadrantectomy and specific antibiotic therapy. We present a case of tuberculous mammary abscess secondary to pulmonary disease, which was treated by percutaneous drainage controlled by CT and specific antibiotic therapy. We revise the diagnosis, differential diagnosis and treatment of mammary tuberculosis. (orig.)

  13. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review

    OpenAIRE

    Lohakare, J. D.; Südekum, K.-H.; A. K. Pattanaik

    2012-01-01

    This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only r...

  14. Coordinate suppression of B cell lymphoma by PTEN and SHIP phosphatases

    DEFF Research Database (Denmark)

    Miletic, Ana V; Anzelon-Mills, Amy N; Mills, David M

    2010-01-01

    results in lethal T cell lymphomas, we find that animals lacking PTEN or SHIP in B cells show no evidence of malignancy. However, concomitant deletion of PTEN and SHIP (bPTEN/SHIP(-/-)) results in spontaneous and lethal mature B cell neoplasms consistent with marginal zone lymphoma or, less frequently......, follicular or centroblastic lymphoma. bPTEN/SHIP(-/-) B cells exhibit enhanced survival and express more MCL1 and less Bim. These cells also express low amounts of p27(kip1) and high amounts of cyclin D3 and thus appear poised to undergo proliferative expansion. Unlike normal B cells, bPTEN/SHIP(-/-) B cells...... proliferate to the prosurvival factor B cell activating factor (BAFF). Interestingly, although BAFF availability may promote lymphoma progression, we demonstrate that BAFF is not required for the expansion of transferred bPTEN/SHIP(-/-) B cells. This study reveals that PTEN and SHIP act cooperatively...

  15. The Development of Novel Small Molecule Inhibitors of the Phosphoinositide- 3-Kinase Pathway through High-Throughput Cell-Based Screens

    Science.gov (United States)

    2007-02-01

    Zhao et al. (2003).ments are currently underway to identify the targets of the re- Cells were grown in mammary epithelial basal medium (MEBM...Sanglier, J.J., and Wang, Y. (1997). Leptomycin B is an inhibitor of nuclear export: inhibition of nucleo -cytoplasmic translocation of the...example, the prostate cancer cell lines PC3 and LNCaP harbor deletions and point mutation of PTEN, rendering each PTEN null. In these cells, basal

  16. RAS/RAF/MEK/ERK and PI3K/PTEN/AKT Signaling in Malignant Melanoma Progression and Therapy

    Directory of Open Access Journals (Sweden)

    Ichiro Yajima

    2012-01-01

    Full Text Available Cutaneous malignant melanoma is one of the most serious skin cancers and is highly invasive and markedly resistant to conventional therapy. Melanomagenesis is initially triggered by environmental agents including ultraviolet (UV, which induces genetic/epigenetic alterations in the chromosomes of melanocytes. In human melanomas, the RAS/RAF/MEK/ERK (MAPK and the PI3K/PTEN/AKT (AKT signaling pathways are two major signaling pathways and are constitutively activated through genetic alterations. Mutations of RAF, RAS, and PTEN contribute to antiapoptosis, abnormal proliferation, angiogenesis, and invasion for melanoma development and progression. To find better approaches to therapies for patients, understanding these MAPK and AKT signaling mechanisms of melanoma development and progression is important. Here, we review MAPK and AKT signaling networks associated with melanoma development and progression.

  17. The mechanism involved in the loss of PTEN expression in NSCLC tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Gang; Zhao, Jingfeng; Peng, Xianjing [Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008 (China); Liang, Jian; Deng, Xin [Ruikang Hospital, Guangxi University of Traditional Chinese Medicine, Nanning 530003 (China); Chen, Yuxiang, E-mail: chenyx008@yahoo.cn [Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008 (China); School of Biological Science and Technology, Central South University, Changsha 410008 (China)

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer Radiation stimulates PTEN reexpression in NSCLC independent of p53 activation. Black-Right-Pointing-Pointer PTEN reexpression is mediated by miR-29b overexpression. Black-Right-Pointing-Pointer miR-29b regulates Dnmts expression in NSCLC tumor cells. Black-Right-Pointing-Pointer Target therapy could be established by overexpressing miR-29b expression. -- Abstract: Loss of PTEN expression is observed in most non-small cell lung cancers (NSCLC). However, the mechanism by which PTEN expression is regulated in NSCLC has not been fully elucidated. In this study, we investigated the role of DNA methyltransferases (Dnmts), microRNA-29b (miR-29b), and anti-miR-29b inhibitor in PTEN promoter methylation and PTEN gene expression in H358 NSCLC cells in vitro and in vivo. PTEN mRNA was measured by RT-PCR. PTEN and Dnmts protein levels were measured by Western blot. miR-29b expression was detected by Northern blot. A xenograft H358 tumor mouse model was established by subcutaneously inoculating H358 cells into the right hind limbs of nude mice. We found that radiation induced cell apoptosis and hypomethylation in PTEN promoter, PTEN and miR-29b expression, and downregulation of Dnmt1, 3a and 3b expression in H358 tumor cells. The effect of radiation on gene expression and apoptosis was blocked by anti-miR-29b inhibitor. In the xenograft H358 tumor model, anti-miR-29b inhibitor reversed radiation-induced tumor growth delay, PTEN reexpression and downregulation of Dnmts expression. Our study suggested that miR-29b is an upstream molecule of PTEN. miR-29b regulates PTEN gene expression through downregulating Dnmts expression and subsequently induces hypomethylation in PTEN promoter. Targeting therapy could be established in NSCLC by upregulating miR-29b expression.

  18. The PTEN/NRF2 Axis Promotes Human Carcinogenesis

    DEFF Research Database (Denmark)

    Rojo, Ana I; Rada, Patricia; Mendiola, Marta;

    2014-01-01

    UNLABELLED: Abstract Aims: A recent study conducted in mice reported that liver-specific knockout of tumor suppressor Pten augments nuclear factor (erythroid-derived 2)-like 2 (NRF2) transcriptional activity. Here, we further investigated how phosphatase and tensin homolog deleted on chromosome 1...

  19. TMPRSS2-ERG and PTEN loss in prostate cancer.

    Science.gov (United States)

    Squire, Jeremy A

    2009-05-01

    Two studies show that the common recurrent gene fusion between TMPRSS2 and ERG promotes prostate cancer in both mouse and humans when PTEN is concurrently lost. In human prostate cancer, the presence of both these aberrations may be indicative of poor prognosis, suggesting that preclinical therapeutic research should target both of these pathways.

  20. Optimization and characterization of an in vitro bovine mammary cell culture system to study regulation of milk protein synthesis and mammary differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Talhouk, R.S.

    1988-01-01

    A long term bovine mammary cell culture system that maintains normal mammary cell function was established and optimized to study milk protein synthesis and secretion and mammary differentiation. This culture system used bovine mammary acini isolated from developing or lactating mammary gland by enzymatic dissociation, and cryopreserved until thawed and plated for growth in vitro for these studies. Cells in M199 with lactogenic hormones {plus minus} fetal calf serum (FCS) were cultured on plastic, 100ul and 500ul type I collagen, and Matrigel, or embedded within type I collagen. Cell morphology, cell number, and total TCA-precipitable {sup 35}S-labelled proteins were monitored. Milk protein ({alpha}{sub s,1}-casein, lactoferrin (LF), {alpha}-lactalbumin, and {beta}-lactoglobulin) secretion and intracellular levels were determined by an ELISA assay.

  1. PI3K/PTEN/Akt and TSC/mTOR signaling pathways, ovarian dysfunction, and infertility: an update.

    Science.gov (United States)

    Makker, Annu; Goel, Madhu Mati; Mahdi, Abbas Ali

    2014-12-01

    Abnormalities in ovarian function, including defective oogenesis and folliculogenesis, represent a key female reproductive deficiency. Accumulating evidence in the literature has shown that the PI3K/PTEN/Akt and TSC/mTOR signaling pathways are critical regulators of ovarian function including quiescence, activation, and survival of primordial follicles, granulosa cell proliferation and differentiation, and meiotic maturation of oocytes. Dysregulation of these signaling pathways may contribute to infertility caused by impaired follicular development, intrafollicular oocyte development, and ovulation. This article reviews the current state of knowledge of the functional role of the PI3K/PTEN/Akt and TSC/mTOR pathways during mammalian oogenesis and folliculogenesis and their association with female infertility.

  2. Cisplatin Induces Overactivation of the Dormant Primordial Follicle through PTEN/AKT/FOXO3a Pathway which Leads to Loss of Ovarian Reserve in Mice

    Science.gov (United States)

    Chang, Eun Mi; Lim, Eunjin; Yoon, Sookyoung; Jeong, Kyungah; Bae, Sijeong; Lee, Dong Ryul; Yoon, Tae Ki

    2015-01-01

    Cisplatin is a first-line chemotherapeutic agent for ovarian cancer that acts by promoting DNA cross links and adduct. However drug resistance and considerable side effects including reproductive toxicity remain a significant challenge. PTEN is well known as a tumor suppressor function which plays a fundamental role in the regulation of the cell cycle, apoptosis and development of cancer. At the same time PTEN has been revealed to be critically important for the maintenance of the primordial follicle pool. In this study, we investigated the role of PTEN/Akt/FOXO3 pathway in cisplatin-induced primordial follicle depletion. Cisplatin induced ovarian failure mouse model was used to evaluate how this pathway involves. In vitro maturation was used for oocyte rescue after cisplatin damage. We found that cisplatin treatment decreased PTEN levels, leading to a subsequent increase in the phosphorylation of key molecules in the pathway. The activation of the PTEN/Akt/FOXO3 pathway cascade increased cytoplasmic translocation of FOXO3a in cisplatin-treated follicles, which in turn increased the pool size of growing follicles, and rapidly depleted the number of dormant follicles. Once activated, the follicles were more prone to apoptosis, and their cumulus cells showed a loss of luteinizing hormone (LH) receptor expression, which leads to failure during final maturation and ovulation. In vitro maturation to rescue oocytes in a cisplatin-treated mouse model resulted in successful maturation and fertilization. This study is the first to show the involvement of the PTEN/Akt/FOXO3 pathway in premature ovarian failure after cisplatin treatment and the possibility of rescue through in vitro maturation. PMID:26656301

  3. Targeting notch pathway enhances rapamycin antitumor activity in pancreas cancers through PTEN phosphorylation

    Directory of Open Access Journals (Sweden)

    Vo Kevin

    2011-11-01

    Full Text Available Abstract Background Pancreas cancer is one of most aggressive human cancers with the survival rate for patients with metastatic pancreas cancer at 5-6 months. The poor survival demonstrates a clear need for better target identification, drug development and new therapeutic strategies. Recent discoveries have shown that the role for Notch pathway is important in both development and cancer. Its contribution to oncogenesis also involves crosstalks with other growth factor pathways, such as Akt and its modulator, PTEN. The mounting evidence supporting a role for Notch in cancer promotion and survival suggests that targeting this pathway alone or in combination with other therapeutics represents a promising therapeutic strategy. Results Using a pancreas cancer tissue microarray, we noted that Jagged1, Notch3 and Notch4 are overexpressed in pancreas tumors (26%, 84% and 31% respectively, whereas Notch1 is expressed in blood vessels. While there was no correlation between Notch receptor expression and survival, stage or tumor grade, Notch3 was associated with Jagged1 and EGFR expression, suggesting a unique relationship between Notch3 and Jagged1. Inhibition of the Notch pathway genetically and with gamma-secretase inhibitor (GSI resulted in tumor suppression and enhanced cell death. The observed anti-tumor activity appeared to be through Akt and modulation of PTEN phosphorylation. We discovered that transcriptional regulation of RhoA by Notch is important for PTEN phosphorylation. Finally, the mTOR inhibitor Rapamycin enhanced the effect of GSI on RhoA expression, resulting in down regulation of phospho-Akt and increased in vitro tumor cytotoxity. Conclusions Notch pathway plays an important role in maintaining pancreas tumor phenotype. Targeting this pathway represents a reasonable strategy for the treatment of pancreas cancers. Notch modulates the Akt pathway through regulation of PTEN phosphorylation, an observation that has not been made

  4. Nonalcoholic fatty liver disease progression in rats is accelerated by splenic regulation of liver PTEN/AKT

    Directory of Open Access Journals (Sweden)

    Ziming Wang

    2015-01-01

    Full Text Available Background/Aim: The spleen has been reported to participate in the development of nonalcoholic fatty liver disease (NAFLD, but the mechanism has not been fully characterized. This study aims to elucidate how the spleen affects the development of NAFLD in a rat model. Materials and Methods: Following either splenectomy or sham operation, male Sprague–Dawley (SD rats were fed a high-fat diet to drive the development of NAFLD; animals fed a normal diet were used as controls. Two months after surgery, livers and blood samples were collected. Serum lipids were measured; liver histology, phosphatase and tensin homologue deleted on chromosome 10 (PTEN gene expression, and the ratio of pAkt/Akt were determined. Results: Splenectomy increased serum lipids, except triglyceride (TG and high-density lipoprotein (HDL, in animals fed either a high-fat or normal diet. Furthermore, splenectomy significantly accelerated hepatic steatosis. Western blot analysis and real-time polymerase chain reaction showed splenectomy induced significant downregulation of PTEN expression and a high ratio of pAkt/Akt in the livers. Conclusions: The spleen appears to play a role in the development of NAFLD, via a mechanism involving downregulation of hepatic PTEN expression.

  5. Heterozygosity for Pten promotes tumorigenesis in a mouse model of medulloblastoma.

    Directory of Open Access Journals (Sweden)

    Robert C Castellino

    Full Text Available BACKGROUND: Recent publications have described an important role for cross talk between PI-3 kinase and sonic hedgehog signaling pathways in the pathogenesis of medulloblastoma. METHODOLOGY/PRINCIPAL FINDINGS: We crossed mice with constitutive activation of Smoothened, SmoA1, with Pten deficient mice. Both constitutive and conditional Pten deficiency doubled the incidence of mice with symptoms of medulloblastoma and resulted in decreased survival. Analysis revealed a clear separation of gene signatures, with up-regulation of genes in the PI-3 kinase signaling pathway, including downstream activation of angiogenesis in SmoA1+/-; Pten +/- medulloblastomas. Western blotting and immunohistochemistry confirmed reduced or absent Pten, Akt activation, and increased angiogenesis in Pten deficient tumors. Down-regulated genes included genes in the sonic hedgehog pathway and tumor suppressor genes. SmoA1+/-; Pten +/+ medulloblastomas appeared classic in histology with increased proliferation and diffuse staining for apoptosis. In contrast, Pten deficient tumors exhibited extensive nodularity with neuronal differentiation separated by focal areas of intense staining for proliferation and virtually absent apoptosis. Examination of human medulloblastomas revealed low to absent PTEN expression in over half of the tumors. Kaplan-Meier analysis confirmed worse overall survival in patients whose tumor exhibited low to absent PTEN expression. CONCLUSIONS/SIGNIFICANCE: This suggests that PTEN expression is a marker of favorable prognosis and mouse models with activation of PI-3 kinase pathways may be important tools for preclinical evaluation of promising agents for the treatment of medulloblastoma.

  6. Parathyroid hormone-related protein activates Wnt signaling to specify the embryonic mammary mesenchyme.

    Science.gov (United States)

    Hiremath, Minoti; Dann, Pamela; Fischer, Jennifer; Butterworth, Daniela; Boras-Granic, Kata; Hens, Julie; Van Houten, Joshua; Shi, Wei; Wysolmerski, John

    2012-11-01

    Parathyroid hormone-related protein (PTHrP) regulates cell fate and specifies the mammary mesenchyme during embryonic development. Loss of PTHrP or its receptor (Pthr1) abolishes the expression of mammary mesenchyme markers and allows mammary bud cells to revert to an epidermal fate. By contrast, overexpression of PTHrP in basal keratinocytes induces inappropriate differentiation of the ventral epidermis into nipple-like skin and is accompanied by ectopic expression of Lef1, β-catenin and other markers of the mammary mesenchyme. In this study, we document that PTHrP modulates Wnt/β-catenin signaling in the mammary mesenchyme using a Wnt signaling reporter, TOPGAL-C. Reporter expression is completely abolished by loss of PTHrP signaling and ectopic reporter activity is induced by overexpression of PTHrP. We also demonstrate that loss of Lef1, a key component of the Wnt pathway, attenuates the PTHrP-induced abnormal differentiation of the ventral skin. To characterize further the contribution of canonical Wnt signaling to embryonic mammary development, we deleted β-catenin specifically in the mammary mesenchyme. Loss of mesenchymal β-catenin abolished expression of the TOPGAL-C reporter and resulted in mammary buds with reduced expression of mammary mesenchyme markers and impaired sexual dimorphism. It also prevented the ectopic, ventral expression of mammary mesenchyme markers caused by overexpression of PTHrP in basal keratinocytes. Therefore, we conclude that a mesenchymal, canonical Wnt pathway mediates the PTHrP-dependent specification of the mammary mesenchyme.

  7. Quantitative Assessment of Mammary Gland Density in Rodents Using Digital Image Analysis

    Directory of Open Access Journals (Sweden)

    Thompson Henry J

    2011-06-01

    Full Text Available Abstract Background Rodent models have been used extensively to study mammary gland development and for studies of toxicology and carcinogenesis. Mammary gland gross morphology can visualized via the excision of intact mammary gland chains following fixation and staining with carmine using a tissue preparation referred to as a whole mount. Methods are described for the automated collection of digital images from an entire mammary gland whole mount and for the interrogation of digital data using a "masking" technique available with Image-Pro® plus image analysis software (Mediacybernetics. Silver Spring, MD. Results Parallel to mammographic analysis in humans, measurements of rodent mammary gland density were derived from area-based or volume-based algorithms and included: total circumscribed mammary fat pad mass, mammary epithelial mass, and epithelium-free fat pad mass. These values permitted estimation of absolute mass of mammary epithelium as well as breast density. The biological plausibility of these measurements was evaluated in mammary whole mounts from rats and mice. During mammary gland development, absolute epithelial mass increased linearly without significant changes in mammographic density. Treatment of rodents with tamoxifen, 9-cis-retinoic acid, or ovariectomy, and occurrence of diet induced obesity decreased both absolute epithelial mass and mammographic density. The area and volumetric methods gave similar results. Conclusions Digital image analysis can be used for screening agents for potential impact on reproductive toxicity or carcinogenesis as well as for mechanistic studies, particularly for cumulative effects on mammary epithelial mass as well as translational studies of mechanisms that explain the relationship between epithelial mass and cancer risk.

  8. Symposium: Role of the extracellular matrix in mammary development. Regulation of milk protein and basement membrane gene expression: The influence of the extracellular matrix

    Energy Technology Data Exchange (ETDEWEB)

    Aggeler, J.; Park, C.S.; Bissell, M.J.

    1988-10-01

    Synthesis and secretion of milk proteins ({alpha}-casein, {beta}-casein, {gamma}-casein, and transferrin) by cultured primary mouse mammary epithelial cells is modulated by the extracellular matrix. In cells grown on released or floating type I collagen gels, mRNA for {beta}-casein and transferrin is increased as much as 30-fold over cells grown on plastic. Induction of {beta}-casein expression depends strongly on the presence of lactogenic hormones, especially prolactin, in the culture. When cells are plated onto partially purified reconstituted basement membrane, dramatic changes in morphology and milk protein gene expression are observed. Cells cultured on the matrix for 6 to 8 d in the presence of prolactin, insulin, and hydrocortisone form hollow spheres and duct-like structures that are completely surrounded by matrix. The cells lining these spheres appear actively secretory and are oriented with their apices facing the lumen. Hybridization experiments indicate that mRNA for {beta}-casein can be increased as much as 70-fold in these cultures. Because > 90% of the cultured cells synthesize immunoreactive {beta}-casein, as compared with only 40% of cells in the late pregnant gland, the matrix appears to be able to induce protein expression in previously silent cells. Synthesis of laminin and assembly of a mammary-specific basal lamina by cells cultured on different extracellular matrices also appears to depend on the presence of lactogenic hormones. These studies provide support for the concept of dynamic reciprocity in which complex interactions between extracellular matrix and the cellular cytoskeleton contribute to the induction and maintenance of tissue-specific gene expression in the mammary gland.

  9. Development of Spontaneous Mammary Tumors in BALB/c-p53+/-Mice: Detection of Early Genetic Alterations and the Mapping of BALB/c Susceptibility Genes

    Science.gov (United States)

    2005-07-01

    of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE 2...processes lead- repurified by Clean and Concentrator (Zymo Research, Orange, CA). The tail ing to LOII in the Mouse mammary gland. and tumor DNAs...modifier of breast cancer risk Anneke C. Blackburn 1,5, Linda Z. Hill ’, Amy L. Roberts 1, Jun Wang 2, Dee Aud 2, Jimmy Jung 2, Tania Nikolcheva 2, John

  10. Expression and function of leptin and its receptor in mouse mammary gland

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Leptin is an autocrine and paracrine factor which affects the development of duct, formation of gland alveolus, expression of milk protein gene and onset involution of mammary gland. In order to know the function and mechanism of leptin in mammary gland, the protein expression and localization of leptin and its long form receptor (OB-Rb) were detected by a confocal laser scanning microscope. To study the impacts of leptin on mammary gland and leptin signal transduction pathway in pregnancy-, lactation- and involution-stage mammary gland, explants were cultured and Western blotting was used. The results showed that in the whole development cycle of mammary gland, the expression of leptin and OB-Rb was in positive correlation. In virgin the leptin expression was the highest and then decreased in pregnancy. In lactation the expression of leptin was low and upgraded in involution, and recovered to the original level about virgin on involution 13 d. The localization of leptin and OB-Rb revealed that leptin induced the expression of OB-Rb specifically and controlled the development and physiological function of the mammary gland by binding to OB-Rb. In pregnancy stage, leptin stimulated proliferation and differentiation of ductal epithelial cells by JAK-MAPK signal pathway. In lactation, leptin induced gene expression of β-casein by JAK-STAT5 signal pathway, and in involution leptin induced mammary epithelial cell apoptosis and mammary gland restitution by JAK-STAT3 signal pathway.

  11. Differentiation of mammary stem cells in vivo and in vitro.

    Science.gov (United States)

    Barraclough, R; Rudland, P S

    1989-03-01

    The fully differentiated cells of the rat mammary parenchyma, the ductal epithelial, alveolar, and myoepithelial cells, are distinguished by their ultrastructure and by their accumulation of immunocytochemically detectable marker proteins. The different cell types probably develop from primative ductal structures called terminal end buds, which are present in the developing rat mammary glands, and these structures contain relatively undifferentiated cells. Clonal epithelial stem cell lines, obtained from normal rat mammary glands or benign mammary tumors, differentiate under appropriate conditions along a pathway to droplet-cell/doming cultures of primative alveolarlike cells. Under different culture conditions, the epithelial stem cells differentiate along a separate pathway to myoepitheliallike cells. They accumulate some of the specific marker proteins of myoepithelial cells in vivo, including type IV collagen, laminin, and Thy-1 antigen. In addition, these myoepitheliallike cells in culture contain an abundance of a potential calcium-binding protein, p9Ka, which also occurs in myoepithelial cells of histological sections from mammary glands. The accumulation of type IV collagen, laminin, Thy-1, and p9Ka occurs asynchronously along the pathway to the myoepitheliallike cells in vitro. Furthermore, the steady-state levels of these different marker proteins arise by alterations in the controls at the transcriptional, the posttranscriptional processing, and the translational stages of their production. These results suggest a stepwise control of synthesis of myoepithelial cell marker proteins, and in the case of p9Ka and Thy-1 antigen, this altered control may arise through their possession of novel transcriptional promoters.

  12. Folic acid supplementation promotes mammary tumor progression in a rat model.

    Science.gov (United States)

    Deghan Manshadi, Shaidah; Ishiguro, Lisa; Sohn, Kyoung-Jin; Medline, Alan; Renlund, Richard; Croxford, Ruth; Kim, Young-In

    2014-01-01

    Folic acid supplementation may prevent the development of cancer in normal tissues but may promote the progression of established (pre)neoplastic lesions. However, whether or not folic acid supplementation can promote the progression of established (pre)neoplastic mammary lesions is unknown. This is a critically important issue because breast cancer patients and survivors in North America are likely exposed to high levels of folic acid owing to folic acid fortification and widespread supplemental use after cancer diagnosis. We investigated whether folic acid supplementation can promote the progression of established mammary tumors. Female Sprague-Dawley rats were placed on a control diet and mammary tumors were initiated with 7,12-dimethylbenza[a]anthracene at puberty. When the sentinel tumor reached a predefined size, rats were randomized to receive a diet containing the control, 2.5x, 4x, or 5x supplemental levels of folic acid for up to 12 weeks. The sentinel mammary tumor growth was monitored weekly. At necropsy, the sentinel and all other mammary tumors were analyzed histologically. The effect of folic acid supplementation on the expression of proteins involved in proliferation, apoptosis, and mammary tumorigenesis was determined in representative sentinel adenocarcinomas. Although no clear dose-response relationship was observed, folic acid supplementation significantly promoted the progression of the sentinel mammary tumors and was associated with significantly higher sentinel mammary tumor weight and volume compared with the control diet. Furthermore, folic acid supplementation was associated with significantly higher weight and volume of all mammary tumors. The most significant and consistent mammary tumor-promoting effect was observed with the 2.5x supplemental level of folic acid. Folic acid supplementation was also associated with an increased expression of BAX, PARP, and HER2. Our data suggest that folic acid supplementation may promote the progression

  13. An activating Pik3ca mutation coupled with Pten loss is sufficient to initiate ovarian tumorigenesis in mice.

    Science.gov (United States)

    Kinross, Kathryn M; Montgomery, Karen G; Kleinschmidt, Margarete; Waring, Paul; Ivetac, Ivan; Tikoo, Anjali; Saad, Mirette; Hare, Lauren; Roh, Vincent; Mantamadiotis, Theo; Sheppard, Karen E; Ryland, Georgina L; Campbell, Ian G; Gorringe, Kylie L; Christensen, James G; Cullinane, Carleen; Hicks, Rodney J; Pearson, Richard B; Johnstone, Ricky W; McArthur, Grant A; Phillips, Wayne A

    2012-02-01

    Mutations in the gene encoding the p110α subunit of PI3K (PIK3CA) that result in enhanced PI3K activity are frequently observed in human cancers. To better understand the role of mutant PIK3CA in the initiation or progression of tumorigenesis, we generated mice in which a PIK3CA mutation commonly detected in human cancers (the H1047R mutation) could be conditionally knocked into the endogenous Pik3ca locus. Activation of this mutation in the mouse ovary revealed that alone, Pik3caH1047R induced premalignant hyperplasia of the ovarian surface epithelium but no tumors. Concomitantly, we analyzed several human ovarian cancers and found PIK3CA mutations coexistent with KRAS and/or PTEN mutations, raising the possibility that a secondary defect in a co-regulator of PI3K activity may be required for mutant PIK3CA to promote transformation. Consistent with this notion, we found that Pik3caH1047R mutation plus Pten deletion in the mouse ovary led to the development of ovarian serous adenocarcinomas and granulosa cell tumors. Both mutational events were required for early, robust Akt activation. Pharmacological inhibition of PI3K/mTOR in these mice delayed tumor growth and prolonged survival. These results demonstrate that the Pik3caH1047R mutation with loss of Pten is enough to promote ovarian cell transformation and that we have developed a model system for studying possible therapies.

  14. CLINICOPATHOLOGICAL SIGNIFICANCE OF PTEN AND CASPASE-3 EXPRESSIONS IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    Xue-fei Yang; Yan Xin; Li-li Mao

    2008-01-01

    Objective To investigate the expressions of PTEN and Caspase-3 proteins in human breast carcinoma, and to evaluate their clinicopathological implications during the tumorigenesis and progression of breast cancer.Methods The expressions of PTEN and Caspase-3 proteins in 95 cases of breast cancer and 15 cases of benignbreast diseases were investigated immunohistochemically. Correlations between the expression of PTEN protein,Caspase-3 protein, and clinicopathological features of breast cancers were analyzed.Results The loss expression rate of PTEN protein in tumor tissues was significantly higher than that in benignbreast diseases (33.7% vs. 0, P 0. 05). In addition,the expression of PTEN protein had significantly positive correlation with the expression of Caspase-3 protein in breast cancer (P <0.01 ).Conclusion The combination detection of PTEN and Caspase-3 may serve as an important index to estimate the pathobiological behavior and pognosis of breast cancer.

  15. PTEN functions to 'prioritize' chemotactic cues and prevent 'distraction' in migrating neutrophils.

    Science.gov (United States)

    Heit, Bryan; Robbins, Stephen M; Downey, Charlene M; Guan, Zhiwen; Colarusso, Pina; Miller, B Joan; Jirik, Frank R; Kubes, Paul

    2008-07-01

    Neutrophils encounter and 'prioritize' many chemoattractants in their pursuit of bacteria. Here we tested the possibility that the phosphatase PTEN is responsible for the prioritization of chemoattractants. Neutrophils induced chemotaxis by two separate pathways, the phosphatidylinositol-3-OH kinase (PI(3)K) phosphatase and tensin homolog (PTEN) pathway, and the p38 mitogen-activated protein kinase pathway, with the p38 pathway dominating over the PI(3)K pathway. Pten(-/-) neutrophils could not prioritize chemoattractants and were 'distracted' by chemokines when moving toward bacterial chemoattractants. In opposing gradients, PTEN became distributed throughout the cell circumference, which inhibited all PI(3)K activity, thus permitting 'preferential' migration toward bacterial products via phospholipase A(2) and p38. Such prioritization was defective in Pten(-/-) neutrophils, which resulted in defective bacterial clearance in vivo. Our data identify a PTEN-dependent mechanism in neutrophils to prioritize, 'triage' and integrate responses to multiple chemotactic cues.

  16. Molecular cloning and characterization of PTEN in the orange-spotted grouper (Epinephelus coioides).

    Science.gov (United States)

    Luo, Sheng-Wei; Wang, Wei-Na; Xie, Ren-Chong; Xie, Fu-Xing; Kong, Jing-Rong; Xiao, Yu-Chao; Huang, Di; Sun, Zuo-Ming; Liu, Yuan; Wang, Cong

    2016-11-01

    PTEN is a key tumor suppressor gene that can play a regulatory role in the cellular proliferation, survival and apoptosis. In this study, the full-length PTEN (EcPTEN) was obtained, containing a 5'UTR of 745 bp, an ORF of 1269 bp and a 3'UTR of 106 bp. The EcPTEN gene encoded a polypeptide of 422 amino acids with an estimated molecular mass of 49.14 KDa and a predicted isoelectric point (pI) of 6.34. The deduced amino acid sequence analysis showed that EcPTEN comprised the conserved residues and the characteristic domains known to the critical functionality of PTEN. qRT-PCR analysis revealed that EcPTEN mRNA was broadly expressed in all the examined tissues, while the highest expression level was observed in liver, followed by the expression in blood, kidney, spleen, heart, gill, muscle and intestine. The groupers challenged with Vibrio alginolyticus showed a sharp increase of EcPTEN mRNA expression in immune tissues. In addition, western blotting analysis confirmed that the up-regulation of EcPTEN protein expression was steadily induced in liver. Subcellular localization analysis indicated that EcPTEN was localized in both nucleus and cytoplasm. Overexpression of EcPTEN can activate the apoptotic cascade and abrogate NF-kB, AP-1, Stat3 and Myc promoter activity in Hela cells. These results indicated that EcPTEN harboring highly-conserved domains with a close sequence similarity to those of PTP superfamily may disrupt the mammalian signalings and play a regulatory role in the apoptotic process.

  17. Adenovirus mediated homozygous endometrial epithelial Pten deletion results in aggressive endometrial carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Ayesha; Ellenson, Lora Hedrick, E-mail: lora.ellenson@med.cornell.edu

    2011-07-01

    Pten is the most frequently mutated gene in uterine endometriod carcinoma (UEC) and its precursor complex atypical hyperplasia (CAH). Because the mutation frequency is similar in CAH and UEC, Pten mutations are thought to occur relatively early in endometrial tumorigenesis. Previous work from our laboratory using the Pten{sup +/-} mouse model has demonstrated somatic inactivation of the wild type allele of Pten in both CAH and UEC. In the present study, we injected adenoviruses expressing Cre into the uterine lumen of adult Pten floxed mice in an attempt to somatically delete both alleles of Pten specifically in the endometrium. Our results demonstrate that biallelic inactivation of Pten results in an increased incidence of carcinoma as compared to the Pten{sup +/-} mouse model. In addition, the carcinomas were more aggressive with extension beyond the uterus into adjacent tissues and were associated with decreased expression of nuclear ER{alpha} as compared to associated CAH. Primary cultures of epithelial and stromal cells were prepared from uteri of Pten floxed mice and Pten was deleted in vitro using Cre expressing adenovirus. Pten deletion was evident in both the epithelial and stromal cells and the treatment of the primary cultures with estrogen had different effects on Akt activation as well as Cyclin D3 expression in the two purified components. This study demonstrates that somatic biallelic inactivation of Pten in endometrial epithelium in vivo results in an increased incidence and aggressiveness of endometrial carcinoma compared to mice carrying a germline deletion of one allele and provides an important in vivo and in vitro model system for understanding the genetic underpinnings of endometrial carcinoma.

  18. Germline disruption of Pten localization causes enhanced sex-dependent social motivation and increased glial production.

    Science.gov (United States)

    Tilot, Amanda K; Gaugler, Mary K; Yu, Qi; Romigh, Todd; Yu, Wanfeng; Miller, Robert H; Frazier, Thomas W; Eng, Charis

    2014-06-15

    PTEN Hamartoma Tumor Syndrome (PHTS) is an autosomal-dominant genetic condition underlying a subset of autism spectrum disorder (ASD) with macrocephaly. Caused by germline mutations in PTEN, PHTS also causes increased risks of multiple cancers via dysregulation of the PI3K and MAPK signaling pathways. Conditional knockout models have shown that neural Pten regulates social behavior, proliferation and cell size. Although much is known about how the intracellular localization of PTEN regulates signaling in cancer cell lines, we know little of how PTEN localization influences normal brain physiology and behavior. To address this, we generated a germline knock-in mouse model of cytoplasm-predominant Pten and characterized its behavioral and cellular phenotypes. The homozygous Pten(m3m4) mice have decreased total Pten levels including a specific drop in nuclear Pten and exhibit region-specific increases in brain weight. The Pten(m3m4) model displays sex-specific increases in social motivation, poor balance and normal recognition memory-a profile reminiscent of some individuals with high functioning ASD. The cytoplasm-predominant protein caused cellular hypertrophy limited to the soma and led to increased NG2 cell proliferation and accumulation of glia. The animals also exhibit significant astrogliosis and microglial activation, indicating a neuroinflammatory phenotype. At the signaling level, Pten(m3m4) mice show brain region-specific differences in Akt activation. These results demonstrate that differing alterations to the same autism-linked gene can cause distinct behavioral profiles. The Pten(m3m4) model is the first murine model of inappropriately elevated social motivation in the context of normal cognition and may expand the range of autism-related behaviors replicated in animal models.

  19. PTEN encoding product: a marker for tumorigenesis and progression of gastric carcinoma

    Institute of Scientific and Technical Information of China (English)

    Lin Yang; Li-Ge Kuang; Hua-Chuan Zheng; Jin-Yi Li; Dong-Ying Wu; Su-Min Zhang; Yan Xin

    2003-01-01

    AIM: To detect the expression of PTEN encoding productin normal mucosa, intestinal metaplasia (IM), dysplasia andcarcinoma of the stomach, and to investigate its clinicalimplication in tumorigenesis and progression of gastriccarcinoma.METHODS: Formalin-fixed paraffin embedded specimens from184 cases of gastric carcinoma, their adjacent normal mucosa,IM and dysplasia were evaluated for PTEN protein expressionby SABC immunohistochemistry. PTEN expression wascompared with tumor stage, lymph node metastasis, Lauren'sand WHO's histological classification of gastric carcinoma.Expression of VEGF was also detected in 60 cases of gastriccarcinoma and its correlation with PTEN was concerned.RESULTS: The positive rates of PTEN protein were 100 %(102/102), 98.5 %(65/66), 66.7 % (4/6) and 47.8 %(88/184)in normal mucosa, IM, dysplasia and carcinoma of the stomach,respectively. The positive rates in dysplasia and carcinomawere lower than in normal mucosa and IM (P<0.01).Advanced gastric cancers expressed less frequent PTEN thanearly gastric cancer (42.9 % v567.6 %, P<0.01). The positiverate of PTEN protein was lower in gastric cancer with thanwithout lymph node metastasis (40.3 % v563.3 %, P<0.01).PTEN was less expressed in diffuse-type than in intestinal-type gastric cancer (41.5 % v557.8 %,P<0.05). Signet ringcell carcinoma showed the expression of PTEN at the lowestlevel (25.0 %, 7/28); less than well and moderatelydifferentiated ones (P<0.01). Expression of PTEN was notcorrelated with expression of VEGF (P>0.05).CONCLUSION: Loss or reduced expression of PTEN proteinoccures commonly in tumorigenesis and progression of gastriccarcinoma. It is suggested that PTEN can be an objective markerfor pathologically biological behaviors of gastric carcinoma.

  20. Dysregulation of AKT Pathway by SMYD2-Mediated Lysine Methylation on PTEN

    OpenAIRE

    Makoto Nakakido; Zhenzhong Deng; Takehiro Suzuki; Naoshi Dohmae; Yusuke Nakamura; Ryuji Hamamoto

    2015-01-01

    Phosphatase and tensin homologue (PTEN), one of the well-characterized tumor suppressor proteins, counteracts the phosphatidylinositol 3-kinase-AKT pathway through its unique lipid phosphatase activity. The functions of PTEN are regulated by a variety of posttranslational modifications such as acetylation, oxidation, ubiquitylation, phosphorylation, and SUMOylation. However, methylation of PTEN has not been reported so far. In this study, we demonstrated that the oncogenic protein lysine meth...

  1. Wnt1 is epistatic to Id2 in inducing mammary hyperplasia, ductal side-branching, and tumors in the mouse

    Directory of Open Access Journals (Sweden)

    Yokota Yoshifumi

    2004-12-01

    Full Text Available Abstract Background During pregnancy, the mammary glands from Id2 mutant animals are deficient in lobulo-alveolar development. This failure of development is believed to be due to a proliferation defect. Methods We have asked whether functional Id2 expression is necessary for Wnt induced mammary hyperplasia, side branching, and cancer, by generating mice expressing a Wnt1 transgene in an Id2 mutant background. Results We show in this work that forced expression of Wnt1 in the mammary gland is capable of overcoming the block to proliferation caused by the absence of Id2. We also show that Wnt1 expression is able to cause mammary tumors in an Id2 mutant background. Conclusions We conclude that functional Id2 expression is not required for Wnt1 to induce mammary hyperplasia and mammary tumors.

  2. Tumor suppressor PTEN affects tau phosphorylation: deficiency in the phosphatase activity of PTEN increases aggregation of an FTDP-17 mutant Tau

    Directory of Open Access Journals (Sweden)

    Zhang Xue

    2006-07-01

    Full Text Available Abstract Background Aberrant hyperphosphorylation of tau protein has been implicated in a variety of neurodegenerative disorders. Although a number of protein kinases have been shown to phosphorylate tau in vitro and in vivo, the molecular mechanisms by which tau phosphorylation is regulated pathophysiologically are largely unknown. Recently, a growing body of evidence suggests a link between tau phosphorylation and PI3K signaling. In this study, phosphorylation, aggregation and binding to the microtubule of a mutant frontal temporal dementia and parkinsonism linked to chromosome 17 (FTDP-17 tau in the presence of tumor suppressor PTEN, a major regulatory component in PI3K signaling, were investigated. Results Phosphorylation of the human mutant FTDP-17 tau, T40RW, was evaluated using different phospho-tau specific antibodies in the presence of human wild-type or phosphatase activity null mutant PTEN. Among the evaluated phosphorylation sites, the levels of Ser214 and Thr212 phospho-tau proteins were significantly decreased in the presence of wild-type PTEN, and significantly increased when the phosphatase activity null mutant PTEN was ectopically expressed. Fractionation of the mutant tau transfected cells revealed a significantly increased level of soluble tau in cytosol when wild-type PTEN was expressed, and an elevated level of SDS-soluble tau aggregates in the presence of the mutant PTEN. In addition, the filter/trap assays detected more SDS-insoluble mutant tau aggregates in the cells overexpressing the mutant PTEN compared to those in the cells overexpressing wild-type PTEN and control DNA. This notion was confirmed by the immunocytochemical experiment which demonstrated that the overexpression of the phosphatase activity null mutant PTEN caused the mutant tau to form aggregates in the COS-7 cells. Conclusion Tumor suppressor PTEN can alleviate the phosporylation of the mutant FTDP-17 tau at specific sites, and the phosphatase activity

  3. PTEN, Stem Cells, and Cancer Stem Cells*S⃞

    OpenAIRE

    Hill, Reginald; Wu, Hong

    2009-01-01

    Like normal stem cells, “cancer stem cells” have the capacity for indefinite proliferation and generation of new cancerous tissues through self-renewal and differentiation. Among the major intracellular signaling pathways, WNT, SHH, and NOTCH are known to be important in regulating normal stem cell activities, and their alterations are associated with tumorigenesis. It has become clear recently that PTEN (phosphatase and tensin homologue) is also critical for stem cell...

  4. Sox10 Regulates Stem/Progenitor and Mesenchymal Cell States in Mammary Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Christopher Dravis

    2015-09-01

    Full Text Available To discover mechanisms that mediate plasticity in mammary cells, we characterized signaling networks that are present in the mammary stem cells responsible for fetal and adult mammary development. These analyses identified a signaling axis between FGF signaling and the transcription factor Sox10. Here, we show that Sox10 is specifically expressed in mammary cells exhibiting the highest levels of stem/progenitor activity. This includes fetal and adult mammary cells in vivo and mammary organoids in vitro. Sox10 is functionally relevant, as its deletion reduces stem/progenitor competence whereas its overexpression increases stem/progenitor activity. Intriguingly, we also show that Sox10 overexpression causes mammary cells to undergo a mesenchymal transition. Consistent with these findings, Sox10 is preferentially expressed in stem- and mesenchymal-like breast cancers. These results demonstrate a signaling mechanism through which stem and mesenchymal states are acquired in mammary cells and suggest therapeutic avenues in breast cancers for which targeted therapies are currently unavailable.

  5. CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells Ex Vivo

    Directory of Open Access Journals (Sweden)

    Benjamin T. Spike

    2014-04-01

    Full Text Available Little is known about the extracellular signaling factors that govern mammary stem cell behavior. Here, we identify CRIPTO and its cell-surface receptor GRP78 as regulators of stem cell behavior in isolated fetal and adult mammary epithelial cells. We develop a CRIPTO antagonist that promotes differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By contrast, CRIPTO treatment maintains the stem cell phenotype in these cultures and yields colonies with enhanced mammary gland reconstitution capacity. Surface expression of GRP78 marks CRIPTO-responsive, stem cell-enriched fetal and adult mammary epithelial cells, and deletion of GRP78 from adult mammary epithelial cells blocks their mammary gland reconstitution potential. Together, these findings identify the CRIPTO/GRP78 pathway as a developmentally conserved regulator of fetal and adult mammary stem cell behavior ex vivo, with implications for the stem-like cells found in many cancers.

  6. CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells Ex Vivo

    Science.gov (United States)

    Spike, Benjamin T.; Kelber, Jonathan A.; Booker, Evan; Kalathur, Madhuri; Rodewald, Rose; Lipianskaya, Julia; La, Justin; He, Marielle; Wright, Tracy; Klemke, Richard; Wahl, Geoffrey M.; Gray, Peter C.

    2014-01-01

    Summary Little is known about the extracellular signaling factors that govern mammary stem cell behavior. Here, we identify CRIPTO and its cell-surface receptor GRP78 as regulators of stem cell behavior in isolated fetal and adult mammary epithelial cells. We develop a CRIPTO antagonist that promotes differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By contrast, CRIPTO treatment maintains the stem cell phenotype in these cultures and yields colonies with enhanced mammary gland reconstitution capacity. Surface expression of GRP78 marks CRIPTO-responsive, stem cell-enriched fetal and adult mammary epithelial cells, and deletion of GRP78 from adult mammary epithelial cells blocks their mammary gland reconstitution potential. Together, these findings identify the CRIPTO/GRP78 pathway as a developmentally conserved regulator of fetal and adult mammary stem cell behavior ex vivo, with implications for the stem-like cells found in many cancers. PMID:24749068

  7. Expression of PPARγ and PTEN in human colorectal cancer: An immunohistochemical study using tissue microarray methodology.

    Science.gov (United States)

    Lin, Mao Song; Huang, Jun Xing; Chen, Wei Chang; Zhang, Bao Feng; Fang, Jing; Zhou, Qiong; Hu, Ying; Gao, Heng Jun

    2011-11-01

    Although aberrations of peroxisome proliferator-activated receptor γ (PPARγ) and phosphatase and tensin homolog (PTEN) expression have been identified in several other cancer types, certain previous studies have revealed that PPARγ is abundant in normal and malignant tissue in the colon. The question of whether aberrant PTEN is involved in the initial stage or is a later event during colorectal carcinogenesis remains controversial. Relatively few studies have focused on the correlation of expression of PPARγ and PTEN in various tissues. In the present study, paraffin-embedded blocks from 139 patients with CRC, 18 adenomatous polyps and 50 paired paracancerous benign mucosas were selected and analysed in 4 tissue microarray (TMA) blocks comprising 104, 72, 130 and 54 cores, respectively. Expression of PPARγ and PTEN was examined using immunohistochemical staining on TMAs. There were no significant differences in the expression of PPARγ (P=0.055) and PTEN (P=0.100) between the colorectal cancers, adenomas and paracancerous mucosas. However, correlations of PPARγ expression with clinical stage (P=0.004) and PTEN expression with histological grade (P=0.006) and distant metastasis (P=0.015) were demonstrated in the CRC specimens. Although the differences in PPARγ and PTEN protein expression in human colorectal cancer may not be considered as early diagnostic markers, our results indicate that CRCs with a low expression or deletion of PTEN may progress towards invasion and even metastasis; thus, PTEN may have potential as a prognostic marker in human CRC.

  8. Hereditary breast cancer associated with Cowden syndrome-related PTEN mutation with Lhermitte-Duclos disease.

    Science.gov (United States)

    Kimura, Fuyo; Ueda, Ai; Sato, Eiichi; Akimoto, Jiro; Kaise, Hiroshi; Yamada, Kimito; Hosonaga, Mari; Kawai, Yuko; Teraoka, Saeko; Okazaki, Miki; Ishikawa, Takashi

    2017-12-01

    Cowden syndrome is characterized by multiple hamartomas in various tissues, including the skin, brain, breast, thyroid, mucous membrane, and gastrointestinal tract, and is reported to increase the risk of malignant disease. We describe the case of a 52-year-old woman in whom a tumor was diagnosed in the left cerebellar hemisphere and treated by surgical resection. Phosphatase and tensin homolog (PTEN) mutation in exon 8 insertion was found in the brain tumor tissue and leukocytes. This finding supported the diagnosis of Cowden syndrome. She consequently developed endometrial cancer and underwent abdominal total hysterectomy with bilateral salpingo-oophorectomy. Four years later, hormone receptor-positive breast cancer was found in the right breast, and breast-conserving surgery with radiation therapy and sentinel lymph node biopsy was performed. Herein, we describe a patient who was diagnosed as having familial breast cancer associated with PTEN mutation-related Cowden syndrome. We also reviewed reports of this syndrome in the literature for disease appraisal.

  9. Postnatal and postpartal morphology of the mammary gland in nude mice.

    Science.gov (United States)

    Militzer, K; Schwalenstöcker, H

    1996-08-01

    The object of this work was to compare the postnatal and postpartal morphology of the mammary gland of nu/nu with that of nu/(+)-mice. All studies were carried out on groups of female (athymic) nude mice with NMRI genetic background, their nu/(+)-siblings and dams. The various age groups (3, 21, 40, 55, 70 and 120 days) each consisted of 6 nu/nu- and 6 heterozygous nu/(+)-mice respectively. The morphological examination of the mammary gland tissue were made on histological sections and whole mounts. Body weights, total areas of the mammary glands and the number of the terminal end buds were compared. The mammary gland of the athymic nude mouse exhibited no essential morphological differences from the normal developing mammary gland of the hairy euthymic nu/(+)-animal. The area of the mammary gland increased with increasing body weight. Both collectives of mice differed only in their rate of mammary gland development. As a result, the terminal end buds appeared numerously as growth points of mammary gland in nu/(+)-animals as early as the 21st day of life. The athymic nude mice showed a maximum only on the 40th day of life and a lower degree of density and differentiation of specific mammary gland structures (lateral buds, lobulo-alveolar glandular endings) until the 70th day of life. The mammary gland of 120-day-old animals and dams of both animal groups reached the same state of maturity. Thus it is not the rate of development of the dam, but other, yet unidentified factors, which determine, if successful breeding of nude mice with homozygous parents is possible.

  10. Mammary Gland Reprogramming: Metalloproteinases Couple Form with Function

    Science.gov (United States)

    Khokha, Rama; Werb, Zena

    2011-01-01

    The adult mammary structure provides for the rapid growth, development, and immunological protection of the live-born young of mammals through its production of milk. The dynamic remodeling of the branched epithelial structure of the mammary gland in response to physiological stimuli that allow its programmed branching morphogenesis at puberty, cyclical turnover during the reproductive cycle, differentiation into a secretory organ at parturition, postlactational involution, and ultimately, regression with age is critical for these processes. Extracellular metalloproteinases are essential for the remodeling programs that operate in the tissue microenvironment at the interface of the epithelium and the stroma, coupling form with function. Deregulated proteolytic activity drives the transition of a physiological mammary microenvironment into a tumor microenvironment, facilitating malignant transformation. PMID:21106646

  11. Use of a Novel Embryonic Mammary Stem Cell Gene Signature to Improve Human Breast Cancer Diagnostics and Therapeutic Decision Making

    Science.gov (United States)

    2014-10-01

    SUBTITLE Use of a Novel Embryonic Mammary Stem Cell Gene Signature to Improve Human Breast Cancer Diagnostics and Therapeutic Decision Making Improve...to determine whether Fetal Mammary Stem Cell (fMaSC) signatures correlate with response to chemotherapy and metastasis in different breast cancer...positioned to achieve its aims. 15. SUBJECT TERMS Breast Cancer Prognosis, Mammary Stem Cells, Embryonic Development, Single Cell Transcriptomics 16

  12. Loss of sfrp1 promotes ductal branching in the murine mammary gland

    Directory of Open Access Journals (Sweden)

    Gauger Kelly J

    2012-08-01

    Full Text Available Abstract Background Secreted frizzled-related proteins (SFRPs are a family of proteins that block the Wnt signaling pathway and loss of SFRP1 expression is found in breast cancer along with a multitude of other human cancers. Activated Wnt signaling leads to inappropriate mammary gland development and mammary tumorigenesis in mice. When SFRP1 is knocked down in immortalized non-malignant mammary epithelial cells, the cells exhibit a malignant phenotype which resembles the characteristics observed in metastatic breast cancer stem-like cells. However, the effects of SFRP1 loss on mammary gland development in vivo are yet to be elucidated. The work described here was initiated to investigate the role of SFRP1 in mammary gland development and whether SFRP1−/− mice exhibit changes in mammary gland morphology and cell signaling pathways shown to be associated with SFRP1 loss in vitro. Results 10 week old nulliparous SFRP1−/− mammary glands exhibited branching with clear lobulo-alveolar development, which normally only occurs in hormonally stimulated mid-pregnant wt mammary glands. Explant cultures of SFRP1−/− mammary glands display increased levels of a well known Wnt signaling target gene, Axin2. Histomorphologic evaluation of virgin glands revealed that by 10 weeks of age, the duct profile is markedly altered in SFRP1−/− mice showing a significantly higher density of ducts with distinct alveoli present throughout the mammary gland, and with focal ductal epithelial hyperplasia. These findings persist as the mice age and are evident at 23 weeks of age. Changes in gene expression, including c-Myc, TGFβ-2, Wnt4, RANKL, and Rspo2 early in mammary gland development are consistent with the excessive hyper branching phenotype. Finally, we found that loss of SFRP1 significantly increases the number of mammary epithelial cells capable of mammosphere formation. Conclusions Our study indicates that SFRP1 gene is critical for maintaining proper

  13. Characterization of Canine Mammary Carcinoma using Dog-Specific cDNA arrays

    OpenAIRE

    Nagesha Appukudige, S.R.

    2008-01-01

    Breast cancer is the most common neoplasm which is frequently diagnosed in women. One in eight women carries a risk of developing breast tumor in her life time. Similarly, mammary tumors in non-spayed female dogs are even more frequent, whereby; one in three female dogs carries a risk of developing mammary tumors in its life time. Ovarian hormones are very important in this context as they are involved in normal development as well as neoplastic transformations of the mammary gland. Among the...

  14. Relationship between PTEN, DNA mismatch repair, and tumor histotype in endometrial carcinoma: retained positive expression of PTEN preferentially identifies sporadic non-endometrioid carcinomas.

    Science.gov (United States)

    Djordjevic, Bojana; Barkoh, Bedia A; Luthra, Rajyalakshmi; Broaddus, Russell R

    2013-10-01

    Loss of PTEN (phosphatase and tensin homolog) expression and microsatellite instability are two of the more common molecular alterations in endometrial carcinoma. From the published literature, it is controversial as to whether there is a relationship between these different molecular mechanisms. Therefore, a cohort of 187 pure endometrioid and non-endometrioid endometrial carcinomas, carefully characterized as to clinical and pathological features, was examined for PTEN sequence abnormalities and the immunohistochemical expression of PTEN and the DNA mismatch repair proteins MLH1, MSH2, MSH6, and PMS2. MLH1 methylation analysis was performed when tumors had loss of MLH1 protein. Mismatch repair protein loss was more frequent in endometrioid carcinomas compared with non-endometrioid carcinomas, a difference primarily attributable to the presence of MLH1 methylation in a greater proportion of endometrioid tumors. Among the non-endometrioid group, mixed endometrioid/non-endometrioid carcinomas were the histotype that most commonly had loss of a mismatch repair protein. In endometrioid tumors, the frequency of PTEN loss measured by immunohistochemistry and mutation did not differ significantly between the mismatch repair protein intact or mismatch repair protein loss groups, suggesting that PTEN loss is independent of mismatch protein repair status in this group. However, in non-endometrioid carcinomas, both intact positive PTEN immunohistochemical expression and PTEN wild type were highly associated with retained positive expression of mismatch repair proteins in the tumor. Relevant to screening endometrial cancers for Lynch Syndrome, an initial PTEN immunohistochemistry determination may be able to replace the use of four mismatch repair immunohistochemical markers in 63% of patients with non-endometrioid endometrial carcinoma. Therefore, PTEN immunohistochemistry, in combination with tumor histotype, is a useful adjunct in the clinical evaluation of endometrial

  15. MUC1 positive, Kras and Pten driven mouse gynecologic tumors replicate human tumors and vary in survival and nuclear grade based on anatomical location.

    Directory of Open Access Journals (Sweden)

    Tejas S Tirodkar

    Full Text Available Activating mutations of Kras oncogene and deletions of Pten tumor suppressor gene play important roles in cancers of the female genital tract. We developed here new preclinical models for gynecologic cancers, using conditional (Cre-loxP mice with floxed genetic alterations in Kras and Pten. The triple transgenic mice, briefly called MUC1KrasPten, express human MUC1 antigen as self and carry a silent oncogenic KrasG12D and Pten deletion mutation. Injection of Cre-encoding adenovirus (AdCre in the ovarian bursa, oviduct or uterus activates the floxed mutations and initiates ovarian, oviductal, and endometrial cancer, respectively. Anatomical site-specific Cre-loxP recombination throughout the genital tract of MUC1KrasPten mice leads to MUC1 positive genital tract tumors, and the development of these tumors is influenced by the anatomical environment. Endometrioid histology was consistently displayed in all tumors of the murine genital tract (ovaries, oviducts, and uterus. Tumors showed increased expression of MUC1 glycoprotein and triggered de novo antibodies in tumor bearing hosts, mimicking the immunobiology seen in patients. In contrast to the ovarian and endometrial tumors, oviductal tumors showed higher nuclear grade. Survival for oviduct tumors was significantly lower than for endometrial tumors (p = 0.0015, yet similar to survival for ovarian cancer. Oviducts seem to favor the development of high grade tumors, providing preclinical evidence in support of the postulated role of fallopian tubes as the originating site for high grade human ovarian tumors.

  16. Immunology of the mammary gland

    Directory of Open Access Journals (Sweden)

    Lazarević Miodrag

    2003-01-01

    Full Text Available The mammary gland is an organ of specific structure whose elementary task is to supply offspring with nutritive and other biologically active substances during the first weeks, or, depending on the species, the first months of life. This prolongs the period of close contact between the mother and her young, which is necessary for their regular growth. Most mammal offspring are born with physiological agammaglobulinaemia, because of the specific structure of the placenta, so that they receive the first specific protection against pathogenic microorganisms through colostrum. Furthermore, this gland is in direct contact with the outer environment through the secretary ducts, so that there are great possibilities for the occurrence of infections. It is therefore necessary to secure protective mechanisms which would prevent such infections. It is clear that there is a distinct connection between the immunological system and the mammary gland, and that link is the central topic of this paper. It presents the basic mechanisms of mammary gland defense which are divided into two categories: nonspecific (innate and specific immune response. The mammary gland secretion contains several types of leukocytes, such as lymphocytes, macrophages, and neutrophiles, as well as 2% epithelial cells. On the average, there are 0.2 x 106 somatic cells in one mililiter of milk. Macrophages account for most of these (58%, as well as lymphocytes (28%, while a smaller number of somatic cells (12% are polymorphonuclears (PMN. The paper considers the characteristics and main functions of these cell types.

  17. Mammary remodeling in primiparous and multiparous dairy goats during lactation

    DEFF Research Database (Denmark)

    Safayi, Sina; Theil, Peter Kappel; Elbrønd, Vibeke Sødring

    2010-01-01

    Milk production is generally lower but lactation persistency higher in primiparous (PP) than in multiparous (MP) goats. This may be related to differences in development and maintenance of mammary gland function, but the underlying mechanisms are not well understood. The present study aimed to el...

  18. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis.

    Science.gov (United States)

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; Min, Kyueng-Whan; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-07-10

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in the mammary glands of MMTV-Id1 transgenic mice. Furthermore, MMTV-Id1 mice develop ductal hyperplasia and mammary tumors with highly expressed basal markers. Id1 also increases breast cancer stem cell (CSC) population and activity in human breast cancer lines. Moreover, the effects of Id1 on normal and malignant stem cell activities are mediated by the Wnt/c-Myc pathway. Collectively, these findings provide in vivo genetic evidence of Id1 functions as an oncogene in breast cancer and indicate that Id1 regulates mammary basal stem cells by activating the Wnt/c-Myc pathway, thereby contributing to breast tumor development.

  19. GRP78 as a regulator of liver steatosis and cancer progression mediated by loss of the tumor suppressor PTEN.

    Science.gov (United States)

    Chen, W-T; Zhu, G; Pfaffenbach, K; Kanel, G; Stiles, B; Lee, A S

    2014-10-16

    Glucose-regulated protein 78 (GRP78), a molecular chaperone widely elevated in human cancers, is critical for endoplasmic reticulum (ER) protein folding, stress signaling and PI3K/AKT activation. Genetic knockout models of GRP78 revealed that GRP78 maintains homeostasis of metabolic organs, including liver, pancreas and adipose tissues. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the most common liver cancers. There is a lack of effective therapeutics for HCC and CC, highlighting the need to further understand liver tumorigenic mechanisms. PTEN (phosphatase and tenson homolog deleted on chromosome 10), a tumor suppressor that antagonizes the PI3K/AKT pathway, is inactivated in a wide range of tumors, including 40-50% of human liver cancers. To elucidate the role of GRP78 in liver cancer, we created a mouse model with biallelic liver-specific deletion of Pten and Grp78 mediated by Albumin-Cre-recombinase (cP(f/f)78(f/f)). Interestingly, in contrast to PTEN, deletion of GRP78 was progressive but incomplete. At 3 months, cP(f/f)78(f/f) livers showed hepatomegaly, activation of lipogenic genes, exacerbated steatosis and liver injury, implying that GRP78 protects the liver against PTEN-null-mediated pathogenesis. Furthermore, in response to liver injury, we observed increased proliferation and expansion of bile duct and liver progenitor cells in cP(f/f)78(f/f) livers. Strikingly, bile duct cells in cP(f/f)78(f/f) livers maintained wild-type (WT) GRP78 level, whereas adjacent areas showed GRP78 reduction. Analysis of signaling pathways revealed selective JNK activation, β-catenin downregulation, along with PDGFRα upregulation, which was unique to cP(f/f)78(f/f) livers at 6 months. Development of both HCC and CC was accelerated and was evident in cP(f/f)78(f/f) livers at 8-9 months, coinciding with intense GRP78 expression in the cancer lesions, and GRP78 expression in adjacent normal areas reverted back to the WT level. In contrast, c78(f/f) livers

  20. High-resolution Structures of Protein-Membrane Complexes by Neutron Reflection and MD Simulation: Membrane Association of the PTEN Tumor Suppressor

    Science.gov (United States)

    Lösche, Matthias

    2012-02-01

    The lipid matrix of biomembranes is an in-plane fluid, thermally and compositionally disordered leaflet of 5 nm thickness and notoriously difficult to characterize in structural terms. Yet, biomembranes are ubiquitous in the cell, and membrane-bound proteins are implicated in a variety of signaling pathways and intra-cellular transport. We developed methodology to study proteins associated with model membranes using neutron reflection measurements and showed recently that this approach can resolve the penetration depth and orientation of membrane proteins with ångstrom resolution if their crystal or NMR structure is known. Here we apply this technology to determine the membrane bindung and unravel functional details of the PTEN phosphatase, a key player in the PI3K apoptosis pathway. PTEN is an important regulatory protein and tumor suppressor that performs its phosphatase activity as an interfacial enzyme at the plasma membrane-cytoplasm boundary. Acting as an antagonist to phosphoinositide-3-kinase (PI3K) in cell signaling, it is deleted in many human cancers. Despite its importance in regulating the levels of the phosphoinositoltriphosphate PI(3,4,5)P3, there is little understanding of how PTEN binds to membranes, is activated and then acts as a phosphatase. We investigated the structure and function of PTEN by studying its membrane affinity and localization on in-plane fluid, thermally disordered synthetic membrane models. The membrane association of the protein depends strongly on membrane composition, where phosphatidylserine (PS) and phosphatidylinositol diphosphate (PI(4,5)P2) act synergetically in attracting the enzyme to the membrane surface. Membrane affinities depend strongly on membrane fluidity, which suggests multiple binding sites on the protein for PI(4,5)P2. Neutron reflection measurements show that the PTEN phosphatase ``scoots'' along the membrane surface (penetration protein, ˜ 60 å away from the bilayer surface, in a rather compact

  1. Genetic aberration of PTEN in peripheral T cell lymphoma, not otherwise specified%非特指外周T细胞淋巴瘤中PTEN的改变

    Institute of Scientific and Technical Information of China (English)

    朱文娟; 张建中

    2012-01-01

    目的 观察非特指外周T细胞淋巴瘤(peripheral T cell lymphoma,not otherwise specified,PTCL-NOS)中抑癌基因(phosphatase and tensin homolog deleted on chromosome ten,PTEN)的改变情况,探讨其与肿瘤生物学行为的关系,为阐明PTCL-NOS的发生、发展机制提供科学依据.方法应用间期双色荧光原位杂交(fluorescence in situ hybridization,FISH)技术检测36例PTCL-NOS石蜡包埋组织中PTEN基因的改变情况,分析其改变与各临床参数的关系.结果 36例PTCL-NOS中8例出现PTEN杂合性缺失(loss of heterozygosity,LOH);Kaplan-Meier生存分析显示该基因异常组较正常组生存期明显缩短(P0.05).结论 PTCL-NOS存在的抑癌基因PTEN杂合性缺失,在PTCL-NOS发生、发展中可能起重要作用,是评估该肿瘤预后的重要指标.%Purpose To investigate the genetic changes of tumor suppressor gene PTEN in PTCL-NOS, and to explore its relationship with the development of PTCL-NOS and other clinicopathological parameters. Methods Thirty-six cases of PTCL-NOS were studied by fluorescence in-situ hybridization ( FISH ) using interphase dual-colour probes. The probes were generated from BAC clones RP11 - 380G5 corresponding to PTEN gene. Correlation of the genetic changes with patients prognosis and other clinical parameters was analyzed. Results Loss of heterozygosity ( LOH ) of PTEN presented in 8/36 cases; Kaplan-Meier survival analysis indicated there was a trend that the group with PTEN gene change had a poorer prognosis than the group without PTEN gene change ( P 0. 05 ). Conclusion A significant percentage of PTCL-NOS carry the genetic alteration of PTEN that may play an important role in the pathogenesis of PTCL-NOS and the e-valuation of the patient' s prognosis.

  2. Cdc6 and Cyclin E2 Are PTEN-Regulated Genes Associated with Human Prostate Cancer Metastasis

    Directory of Open Access Journals (Sweden)

    Zhong Wu

    2009-01-01

    Full Text Available Phosphatase and tensin homolog deleted on chromosome 10 (PTEN is frequently inactivated in metastatic prostate cancer, yet the molecular consequences of this and their association with the metastatic phenotype are incompletely understood. We performed transcriptomic analysis and identified genes altered by conditional PTEN reexpression in C4-2, a human metastatic prostate cancer cell line with inactive PTEN. PTEN-regulated genes were disproportionately represented among genes altered in human prostate cancer progression and metastasis but not among those associated with tumorigenesis. From the former set, we identified two novel putative PTEN targets, cdc6 and cyclin E2, which were overexpressed in metastatic human prostate cancer and up-regulated as a function of PTEN depletion in poorly metastatic DU145 human prostate cancer cells harboring a wild type PTEN. Inhibition of cdc6 and cyclin E2 levels as a consequence of PTEN expression was associated with cell cycle G1 arrest, whereas use of PTEN activity mutants revealed that regulation of these genes was dependent on PTEN lipid phosphatase activity. Computational and promoter-reporter evaluations implicated the E2F transcription factor in PTEN regulation of cdc6 and cyclin E2 expression. Our results suggest a hypothetical model whereby PTEN loss upregulates cell cycle genes such as cdc6 and cyclin E2 that in turn promote metastatic colonization at distant sites.

  3. Studies of variability in the PTEN gene among Danish caucasian patients with Type II diabetes mellitus

    DEFF Research Database (Denmark)

    Hansen, L; Jensen, J N; Ekstrøm, C T

    2001-01-01

    Phosphatase and tensin homologue deleted from chromosome ten (PTEN) has recently been characterized as a novel member in the expanding network of proteins regulating the intracellular effects of insulin. By dephosphorylation of phosphatidyl-inositol-(3, 4, 5)-trisphosphate (PIP3) the PTEN protein...

  4. Planarian PTEN homologs regulate stem cells and regeneration through TOR signaling.

    Science.gov (United States)

    Oviedo, Néstor J; Pearson, Bret J; Levin, Michael; Sánchez Alvarado, Alejandro

    2008-01-01

    We have identified two genes, Smed-PTEN-1 and Smed-PTEN-2, capable of regulating stem cell function in the planarian Schmidtea mediterranea. Both genes encode proteins homologous to the mammalian tumor suppressor, phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Inactivation of Smed-PTEN-1 and -2 by RNA interference (RNAi) in planarians disrupts regeneration, and leads to abnormal outgrowths in both cut and uncut animals followed soon after by death (lysis). The resulting phenotype is characterized by hyperproliferation of neoblasts (planarian stem cells), tissue disorganization and a significant accumulation of postmitotic cells with impaired differentiation capacity. Further analyses revealed that rapamycin selectively prevented such accumulation without affecting the normal neoblast proliferation associated with physiological turnover and regeneration. In animals in which PTEN function is abrogated, we also detected a significant increase in the number of cells expressing the planarian Akt gene homolog (Smed-Akt). However, functional abrogation of Smed-Akt in Smed-PTEN RNAi-treated animals does not prevent cell overproliferation and lethality, indicating that functional abrogation of Smed-PTEN is sufficient to induce abnormal outgrowths. Altogether, our data reveal roles for PTEN in the regulation of planarian stem cells that are strikingly conserved to mammalian models. In addition, our results implicate this protein in the control of stem cell maintenance during the regeneration of complex structures in planarians.

  5. Characterization of cryptic splicing in germline PTEN intronic variants in Cowden syndrome.

    Science.gov (United States)

    Chen, Hannah Jinlian; Romigh, Todd; Sesock, Kaitlin; Eng, Charis

    2017-10-01

    Germline mutations in the tumor-suppressor gene PTEN predispose to subsets of Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome, and autism. Evidence-based classification of PTEN variants as either deleterious or benign is urgently needed for accurate molecular diagnosis and gene-informed genetic counseling. We studied 34 different germline PTEN intronic variants from 61 CS patients, characterized their PTEN mRNA processing, and analyzed PTEN expression and downstream readouts of P-AKT and P-ERK1/2. While we found that many mutations near splice junctions result in exon skipping, we also identified the presence of cryptic splicing that resulted in premature termination or a shift in isoform usage. PTEN protein expression is significantly lower in the group with splicing changes while P-AKT, but not P-ERK1/2, is significantly increased. Our observations of these PTEN intronic variants should contribute to the determination of pathogenicity of PTEN intronic variants and aid in genetic counseling. © 2017 The Authors. Human Mutation published by Wiley Periodicals, Inc.

  6. Systematic analysis of the PTEN 5' leader identifies a major AUU initiated proteoform.

    Science.gov (United States)

    Tzani, Ioanna; Ivanov, Ivaylo P; Andreev, Dmitri E; Dmitriev, Ruslan I; Dean, Kellie A; Baranov, Pavel V; Atkins, John F; Loughran, Gary

    2016-05-01

    Abundant evidence for translation within the 5' leaders of many human genes is rapidly emerging, especially, because of the advent of ribosome profiling. In most cases, it is believed that the act of translation rather than the encoded peptide is important. However, the wealth of available sequencing data in recent years allows phylogenetic detection of sequences within 5' leaders that have emerged under coding constraint and therefore allow for the prediction of functional 5' leader translation. Using this approach, we previously predicted a CUG-initiated, 173 amino acid N-terminal extension to the human tumour suppressor PTEN. Here, a systematic experimental analysis of translation events in the PTEN 5' leader identifies at least two additional non-AUG-initiated PTEN proteoforms that are expressed in most human cell lines tested. The most abundant extended PTEN proteoform initiates at a conserved AUU codon and extends the canonical AUG-initiated PTEN by 146 amino acids. All N-terminally extended PTEN proteoforms tested retain the ability to downregulate the PI3K pathway. We also provide evidence for the translation of two conserved AUG-initiated upstream open reading frames within the PTEN 5' leader that control the ratio of PTEN proteoforms.

  7. Opening the conformation is a master switch for the dual localization and phosphatase activity of PTEN

    Science.gov (United States)

    Nguyen, Hoai-Nghia; Yang, Jr-Ming; Miyamoto, Takafumi; Itoh, Kie; Rho, Elmer; Zhang, Qiang; Inoue, Takanari; Devreotes, Peter N.; Sesaki, Hiromi; Iijima, Miho

    2015-01-01

    Tumor suppressor PTEN mainly functions at two subcellular locations, the plasma membrane and the nucleus. At the plasma membrane, PTEN dephosphorylates the tumorigenic second messenger PIP3, which drives cell proliferation and migration. In the nucleus, PTEN controls DNA repair and genome stability independently of PIP3. Whereas the concept that a conformational change regulates protein function through post-translational modifications has been well established in biology, it is unknown whether a conformational change simultaneously controls dual subcellular localizations of proteins. Here, we discovered that opening the conformation of PTEN is the crucial upstream event that determines its key dual localizations of this crucial tumor suppressor. We identify a critical conformational switch that regulates PTEN’s localization. Most PTEN molecules are held in the cytosol in a closed conformation by intramolecular interactions between the C-terminal tail and core region. Dephosphorylation of the tail opens the conformation and exposes the membrane-binding regulatory interface in the core region, recruiting PTEN to the membrane. Moreover, a lysine at residue 13 is also exposed and when ubiquitinated, transports PTEN to the nucleus. Thus, opening the conformation of PTEN is a key mechanism that enhances its dual localization and enzymatic activity, providing a potential therapeutic strategy in cancer treatments. PMID:26216063

  8. Construction and Expression of Human PTEN Tumor Suppressor Gene Recombinant Adenovirus Vector

    Institute of Scientific and Technical Information of China (English)

    CHEN Qingyong; WANG Chunyou; CHEN Daoda; CHEN Jianying; JIANG Chunfang; ZHENG Hai

    2006-01-01

    The recombinant defective adenovirus vector carrying human PTEN tumor suppres sor gene was constructed by using AdEasy-1 system and its expression was detected in human breast cancer cell line MDA-MB-468. Human PTEN cDNA was cloned into adenovirus shuttle plasmid pAdTrack-CMV to generate a recombinant plasmid pAdTrack-CMV-PTEN, then homologeous recombination was carried out in the E. coli BJ5183 by contransforming linearized shuttle vector with adenovirus backbone plasmid pAdEasy-1. The newly recombined defective adenovirus vector AdPTEN containing green fluorescent protein (GFP) was packaged and propagated in 293 cells. After being purified by cesium chloride gradient centrifugation, the adenovirus was transfected into human breast cancer cell line MDA-MB-468 in vitro. The expression of PTEN mRNA and protein in infected human breast cancer cell line MDA-MB-468 was detected by RT-PCR and Western blot respectively. The recombinant defective adenovirus vector carrying PTEN gene was constructed successfully. The viral titer of purified adenovirus was 2.5×1010 pfu/mL, and about 70 % breast cancer cells were infected with Ad PTEN when multiplicity of infection (MOI) reached 50. The exogenous PTEN mRNA and protein were expressed in MDA-MB-468 cells infected with Ad-PTEN by RT-PCR and Western blot. The recombinant defective adenovirus vector of PTEN gene was constructed successfully using AdEasy-1 system rapidly, which paved a sound foundation for gene study of breast cancer.

  9. The role of PTEN in chronic growth hormone-induced hepatic insulin resistance.

    Science.gov (United States)

    Gao, Yuan; Su, Peizhu; Wang, Chuqiong; Zhu, Kongqin; Chen, Xiaolan; Liu, Side; He, Jiman

    2013-01-01

    Chronic growth hormone (GH) therapy has been shown to cause insulin resistance, but the mechanism remains unknown. PTEN, a tumor suppressor gene, is a major negative regulator of insulin signaling. In this study, we explored the effect of chronic GH on insulin signaling in the context of PTEN function. Balb/c healthy mice were given recombinant human or bovine GH intraperitoneally for 3 weeks. We found that phosphorylation of Akt was significantly decreased in chronic GH group and the expression of PTEN was significantly increased. We further examined this effect in the streptozotocin-induced Type I diabetic mouse model, in which endogenous insulin secretion was disrupted. Insulin/PI3K/Akt signaling was impaired. However, different from the observation in healthy mice, the expression of PTEN did not increase. Similarly, PTEN expression did not significantly increase in chronic GH-treated mice with hypoinsulinemia induced by prolonged fasting. We conducted in-vitro experiments in HepG2 cells to validate our in-vivo findings. Long-term exposure to GH caused similar resistance of insulin/PI3K/Akt signaling in HepG2 cells; and over-expression of PTEN enhanced the impairment of insulin signaling. On the other hand, disabling the PTEN gene by transfecting the mutant PTEN construct C124S or siPTEN, disrupted the chronic GH induced insulin resistance. Our data demonstrate that PTEN plays an important role in chronic-GH-induced insulin resistance. These findings may have implication in other pathological insulin resistance.

  10. Molecular characterization and function of a PTEN gene from Litopenaeus vannamei after Vibrio alginolyticus challenge.

    Science.gov (United States)

    Xie, C-y; Kong, J-r; Zhao, C-s; Xiao, Y-c; Peng, T; Liu, Y; Wang, W-n

    2016-06-01

    PTEN, a tumor suppressor gene, suppresses cell survival, growth, apoptosis, cell migration and DNA damage repair by inhibiting the PI3K/AKT signaling pathway. In this study, the full-length Litopenaeus vannamei PTEN (LvPTEN) cDNA was obtained, containing a 5'UTR of 59bp, an ORF of 1269bp and a 3'UTR of 146bp besides the poly (A) tail. The PTEN gene encoded a protein of 422 amino acids with an estimated molecular mass of 48.3 KDa and a predicted isoelectric point (pI) of 7.6. Subcellular localization analysis revealed that LvPTEN was distributed in both cytoplasm and nucleus, and the tissue distribution patterns showed that LvPTEN was ubiquitously expressed in all the examined tissues. Vibrio alginolyticus challenge induced upregulation of LvPTEN expression. Moreover, RNAi knock-down of LvPTEN in vivo significantly increased the expression of LvAKT mRNA, while reducing that of the downstream apoptosis genes LvP53 and LvCaspase3. LvPTEN knock-down also caused a sharp increase in cumulative mortality, bacterial numbers, and DNA damage in the hemolymph of L. vannamei following V. alginolyticus challenge, together with a sharp decrease in the total hemocyte count (THC). These results suggested that LvPTEN may participate in apoptosis via the PI3K/AKT signaling pathway in L. vannamei, and play an important role in shrimp innate immunity.

  11. Downregulation of PTEN at Corneal Wound Sites Accelerates Wound Healing through Increased Cell Migration

    Science.gov (United States)

    Cao, Lin; Graue-Hernandez, Enrique O.; Tran, Vu; Reid, Brian; Pu, Jin; Mannis, Mark J.

    2011-01-01

    Purpose. The PI3K/Akt pathway is required for cell polarization and migration, whereas the phosphatase and tensin homologue deleted on chromosome 10 (PTEN) has inhibitory effects on the PI3K/Akt pathway. The authors therefore hypothesized that wounding would downregulate PTEN and that this downregulation would enhance wound healing. Methods. In human corneal epithelial (HCE) cell monolayer and rat cornea scratch wound models, the authors investigated PTEN and Akt expression using Western blot and immunofluorescence analyses. The effects of PTEN and PI3K inhibitors dipotassium bisperoxo (picolinato) oxovanadate (bpv(pic)) and LY294002 on cell migration and wound closure were investigated using time-lapse imaging. Finally, the authors investigated the effect of PTEN inhibition on wound healing in whole rat eyes. Results. In HCE cell monolayer and rat cornea, PTEN was downregulated at the wound edges within 30 minutes of wounding. The downregulation of PTEN was causal in a simultaneous increase in Akt activation, which was responsible for a significant increase in individual cell migration rate from 8.8 μm/h to 17.3 μm/h. An increased migration rate was maintained for 20 hours. PTEN inhibition significantly enhanced the wound healing rate in the HCE cell monolayer from 10 minutes onward after treatment and reduced the healing time in eye organ culture from 30 to 20 hours. Conclusions. Injury to the corneal epithelium downregulates the expression of PTEN at wound edges, allowing increased PI3K/Akt signaling, thereby contributing to a significant enhancement of cell migration and wound healing. These results suggest that PTEN inhibition may be an effective treatment for corneal injury. PMID:21212174

  12. Loss of PTEN causes SHP2 activation, making lung cancer cells unresponsive to IFN-γ

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chia-Ling [Translational Research Center, Taipei Medical University, Taipei 110, Taiwan (China); Chiang, Tzu-Hui; Tseng, Po-Chun [Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan (China); Wang, Yu-Chih [Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Lin, Chiou-Feng, E-mail: cflin2014@tmu.edu.tw [Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan (China)

    2015-10-23

    Src homology-2 domain-containing phosphatase (SHP) 2, an oncogenic phosphatase, inhibits type II immune interferon (IFN)-γ signaling by subverting signal transducers and activators of transcription 1 tyrosine phosphorylation and activation. For cancer immunoediting, this study aimed to investigate the decrease of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a tumor suppressor protein, leading to cellular impairment of IFN-γ signaling. In comparison with human lung adenocarcinoma A549 cells, the natural PTEN loss in another human lung adenocarcinoma line, PC14PE6/AS2 cells, presents reduced responsiveness in IFN-γ-induced IFN regulatory factor 1 activation and CD54 expression. Artificially silencing PTEN expression in A549 cells also caused cells to be unresponsive to IFN-γ without affecting IFN-γ receptor expression. IFN-γ-induced inhibition of cell proliferation and cytotoxicity were demonstrated in A549 cells but were defective in PC14PE6/AS2 cells and in PTEN-deficient A549 cells. Aberrant activation of SHP2 by ROS was specifically shown in PC14PE6/AS2 cells and PTEN-deficient A549 cells. Inhibiting ROS and SHP2 rescued cellular responses to IFN-γ-induced cytotoxicity and inhibition of cell proliferation in PC14PE6/AS2 cells. These results demonstrate that a decrease in PTEN facilitates ROS/SHP2 signaling, causing lung cancer cells to become unresponsive to IFN-γ. - Highlights: • This study demonstrates that PTEN decrease causes cellular unresponsive to IFN-γ. • Lung cancer cells with PTEN deficiency show unresponsive to IFN-γ signaling. • PTEN decrease inhibits IFN-γ-induced CD54, cell proliferation inhibition, and cytotoxicity. • ROS-mediated SHP2 activation makes PTEN-deficient cells unresponsive to IFN-γ.

  13. Notch3 marks clonogenic mammary luminal progenitor cells in vivo.

    Science.gov (United States)

    Lafkas, Daniel; Rodilla, Veronica; Huyghe, Mathilde; Mourao, Larissa; Kiaris, Hippokratis; Fre, Silvia

    2013-10-14

    The identity of mammary stem and progenitor cells remains poorly understood, mainly as a result of the lack of robust markers. The Notch signaling pathway has been implicated in mammary gland development as well as in tumorigenesis in this tissue. Elevated expression of the Notch3 receptor has been correlated to the highly aggressive "triple negative" human breast cancer. However, the specific cells expressing this Notch paralogue in the mammary gland remain unknown. Using a conditionally inducible Notch3-CreERT2(SAT) transgenic mouse, we genetically marked Notch3-expressing cells throughout mammary gland development and followed their lineage in vivo. We demonstrate that Notch3 is expressed in a highly clonogenic and transiently quiescent luminal progenitor population that gives rise to a ductal lineage. These cells are capable of surviving multiple successive pregnancies, suggesting a capacity to self-renew. Our results also uncover a role for the Notch3 receptor in restricting the proliferation and consequent clonal expansion of these cells.

  14. Collagen density promotes mammary tumor initiation and progression

    Directory of Open Access Journals (Sweden)

    Knittel Justin G

    2008-04-01

    Full Text Available Abstract Background Mammographically dense breast tissue is one of the greatest risk factors for developing breast carcinoma. Despite the strong clinical correlation, breast density has not been causally linked to tumorigenesis, largely because no animal model has existed for studying breast tissue density. Importantly, regions of high breast density are associated with increased stromal collagen. Thus, the influence of the extracellular matrix on breast carcinoma development and the underlying molecular mechanisms are not understood. Methods To study the effects of collagen density on mammary tumor formation and progression, we utilized a bi-transgenic tumor model with increased stromal collagen in mouse mammary tissue. Imaging of the tumors and tumor-stromal interface in live tumor tissue was performed with multiphoton laser-scanning microscopy to generate multiphoton excitation and spectrally resolved fluorescent lifetimes of endogenous fluorophores. Second harmonic generation was utilized to image stromal collagen. Results Herein we demonstrate that increased stromal collagen in mouse mammary tissue significantly increases tumor formation approximately three-fold (p p Conclusion This study provides the first data causally linking increased stromal collagen to mammary tumor formation and metastasis, and demonstrates that fundamental differences arise and persist in epithelial tumor cells that progressed within collagen-dense microenvironments. Furthermore, the imaging techniques and signature identified in this work may provide useful diagnostic tools to rapidly assess fresh tissue biopsies.

  15. Detecting PTEN and PI3K signaling in brain

    Science.gov (United States)

    Zhu, Guo; Baker, Suzanne J.

    2016-01-01

    Summary The central nervous system is comprised of multiple cell types including neurons, glia and other supporting cells that may differ dramatically in levels of signaling pathway activation. Immunohistochemistry in conjunction with drug interference are powerful tools that allow evaluation of signaling pathways in different cell types of the mouse central nervous system in vivo. Here we provide detailed protocols for immunohistochemistry to evaluate three essential components in the PI3K pathway in mouse brain: Pten, p-Akt and p-4ebp1, and for rapamycin treatment to modulate mTOR signaling in vivo. PMID:27033070

  16. Conditionally reprogrammed normal and transformed mouse mammary epithelial cells display a progenitor-cell-like phenotype.

    Directory of Open Access Journals (Sweden)

    Francisco R Saenz

    Full Text Available Mammary epithelial (ME cells cultured under conventional conditions senesce after several passages. Here, we demonstrate that mouse ME cells isolated from normal mammary glands or from mouse mammary tumor virus (MMTV-Neu-induced mammary tumors, can be cultured indefinitely as conditionally reprogrammed cells (CRCs on irradiated fibroblasts in the presence of the Rho kinase inhibitor Y-27632. Cell surface progenitor-associated markers are rapidly induced in normal mouse ME-CRCs relative to ME cells. However, the expression of certain mammary progenitor subpopulations, such as CD49f+ ESA+ CD44+, drops significantly in later passages. Nevertheless, mouse ME-CRCs grown in a three-dimensional extracellular matrix gave rise to mammary acinar structures. ME-CRCs isolated from MMTV-Neu transgenic mouse mammary tumors express high levels of HER2/neu, as well as tumor-initiating cell markers, such as CD44+, CD49f+, and ESA+ (EpCam. These patterns of expression are sustained in later CRC passages. Early and late passage ME-CRCs from MMTV-Neu tumors that were implanted in the mammary fat pads of syngeneic or nude mice developed vascular tumors that metastasized within 6 weeks of transplantation. Importantly, the histopathology of these tumors was indistinguishable from that of the parental tumors that develop in the MMTV-Neu mice. Application of the CRC system to mouse mammary epithelial cells provides an attractive model system to study the genetics and phenotype of normal and transformed mouse epithelium in a defined culture environment and in vivo transplant studies.

  17. HORMONAL INFLUENCES ON MAMMARY TUMORS OF THE RAT

    Science.gov (United States)

    Huggins, Charles; Torralba, Yolanda; Mainzer, Klaus

    1956-01-01

    growth of the tumor until a peak was achieved; an increase of the dose above the optimal amount depressed the growth of the tumor. The stage of depression of growth was not observed in the mammary glands of these tumor-bearing rats. Many steroids which induced gestational changes in the mammary gland accelerated the growth of the tumor. Among these were estrone and progesterone in combination and 17α-ethinyl-19-nor-testosterone administered alone. But gestational changes developed in the mammary gland of rats treated with 4-androstene-3α,17β-diol, without growth of the tumor. The evidence which we have presented proves that the mammary fibroadenoma tested had some of the functional properties of a normal mammary gland, and neoplastic traits as well. In its response to hormones it had characteristics which set it apart from all other endocrine targets of the rat. PMID:13367328

  18. 抑癌基因PTEN蛋白在肾癌细胞中的表达及病变评估中的意义%Expression of Tumor Suppressor Gene PTEN in Renal Cell Carcinoma and Its Significance

    Institute of Scientific and Technical Information of China (English)

    李金雨; 谢庆祥; 韩聪祥; 赵力; 林吓聪

    2012-01-01

    [Objective]To explore the expression of tumor suppressor gene PTEN in renal cell carcinoma (RCC) and its impact on cell cycle. [Methods] Totally 44 cases of RCC tissues confirmed by pathology after operation, 15 cases of adjacent normal renal cell tissues and 10 cases of non-tumor normal renal tissues were collected. Immunohistochemical SP method was used to detect PTEN protein. Fifteen RCC tissues were selected respectively from renal tissues with positive and negative PTEN protein. Flow cytometry was used to examine the cell cycle. [Results]The expression of PTEN protein mostly located in the renal cell cytoplasm. The positive expression of PTEN protein in RCC tissues was 36. 3% , which was prominently lower than those in the adjacent normal tissues(77. 3%) and the normal tissues(100%) ( P <0. 01). The expression of PTEN in RCC tissues with stage I and H were much higher than those in RCC tissues with stage HI and IV ( P <0. 05). The percentage of Go/Gi phase in renal cancer with positive expression of PTEN protein was mush higher than that in renal cancer with negative expression of PTEN protein( P <0. 01) , but the percentage of G2/M and S phase in renal cancer with positive expression of PTEN protein was mush lower than that in renal cancer with negative expression of PTEN protein( P <0. 01). [Conclusion]The positive expression of PTEN protein in RCC tissues significantly decreases. PTEN protein may suppress renal carcinoma through inducing the cell cycle to be arrested in G0/G1 phase. The expression of PTEN protein can evaluate the development and prognosis of RCC.%[目的]探讨肾细胞癌(renal cell carcinoma,RCC)中的抑癌基因PTEN蛋白的表达及其对肾癌细胞周期的影响.[方法]收集44例手术后并经病理学检查证实的RCC组织、15 例癌旁非癌肾组织及10例非瘤正常肾组织,采用免疫组化SP法进行PTEN蛋白检测,按PTEN蛋白阴、阳性各选15例RCC组织,用流式细胞仪检测细胞周期.[结果]PTEN蛋白

  19. Enzymes of the taurine biosynthetic pathway are expressed in rat mammary gland.

    Science.gov (United States)

    Ueki, Iori; Stipanuk, Martha H

    2007-08-01

    Taurine is the most abundant free amino acid in the body and is present at high concentrations during development and in the early milk. It is synthesized from cysteine via oxidation of cysteine to cysteinesulfinate by the enzyme cysteine dioxygenase (CDO), followed by the decarboxylation of cysteinesulfinate to hypotaurine, catalyzed by cysteine sulfinic acid decarboxylase (CSAD). To determine whether the taurine biosynthetic pathway is present in mammary gland and whether it is differentially expressed during pregnancy and lactation, and also to further explore the possible regulation of hepatic taurine synthesis during pregnancy and lactation, we measured mammary and hepatic CDO and CSAD mRNA and protein concentrations and tissue, plasma and milk taurine concentrations. CDO and CSAD mRNA and protein were expressed in mammary gland and liver regardless of physiological state. Immunohistochemistry demonstrated the expression of CDO in ductal cells of pregnant rats, but not in other mammary epithelial cells or in ductal cells of nonpregnant rats. CDO was also present in stromal adipocytes in mammary glands of both pregnant and nonpregnant rats. Our findings support an upregulation of taurine synthetic capacity in the mammary gland of pregnant rats, based on mammary taurine and hypotaurine concentrations and the intense immunohistochemical staining for CDO in ductal cells of pregnant rats. Hepatic taurine synthetic capacity, particularly CSAD, and taurine concentrations were highest in rats during the early stages of lactation, suggesting the liver may also play a role in the synthesis of taurine to support lactation or repletion of maternal reserves.

  20. p130Cas over-expression impairs mammary branching morphogenesis in response to estrogen and EGF.

    Directory of Open Access Journals (Sweden)

    Maria del Pilar Camacho Leal

    Full Text Available p130Cas adaptor protein regulates basic processes such as cell cycle control, survival and migration. p130Cas over-expression has been related to mammary gland transformation, however the in vivo consequences of p130Cas over-expression during mammary gland morphogenesis are not known. In ex vivo mammary explants from MMTV-p130Cas transgenic mice, we show that p130Cas impairs the functional interplay between Epidermal Growth Factor Receptor (EGFR and Estrogen Receptor (ER during mammary gland development. Indeed, we demonstrate that p130Cas over-expression upon the concomitant stimulation with EGF and estrogen (E2 severely impairs mammary morphogenesis giving rise to enlarged multicellular spherical structures with altered architecture and absence of the central lumen. These filled acinar structures are characterized by increased cell survival and proliferation and by a strong activation of Erk1/2 MAPKs and Akt. Interestingly, antagonizing the ER activity is sufficient to re-establish branching morphogenesis and normal Erk1/2 MAPK activity. Overall, these results indicate that high levels of p130Cas expression profoundly affect mammary morphogenesis by altering epithelial architecture, survival and unbalancing Erk1/2 MAPKs activation in response to growth factors and hormones. These results suggest that alteration of morphogenetic pathways due to p130Cas over-expression might prime mammary epithelium to tumorigenesis.

  1. Lgr5-Expressing Cells Are Sufficient and Necessary for Postnatal Mammary Gland Organogenesis

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    Vicki Plaks

    2013-01-01

    Full Text Available Mammary epithelial stem cells are vital to tissue expansion and remodeling during various phases of postnatal mammary development. Basal mammary epithelial cells are enriched in Wnt-responsive cells and can reconstitute cleared mammary fat pads upon transplantation into mice. Lgr5 is a Wnt-regulated target gene and was identified as a major stem cell marker in the small intestine, colon, stomach, and hair follicle, as well as in kidney nephrons. Here, we demonstrate the outstanding regenerative potential of a rare population of Lgr5-expressing (Lgr5+ mammary epithelial cells (MECs. We found that Lgr5+ cells reside within the basal population, are superior to other basal cells in regenerating functional mammary glands (MGs, are exceptionally efficient in reconstituting MGs from single cells, and exhibit regenerative capacity in serial transplantations. Loss-of-function and depletion experiments of Lgr5+ cells from transplanted MECs or from pubertal MGs revealed that these cells are not only sufficient but also necessary for postnatal mammary organogenesis.

  2. Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression

    NARCIS (Netherlands)

    Gracanin, Ana; Timmermans-Sprang, Elpetra P M; van Wolferen, Monique E; Rao, Nagesha A S; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism o

  3. Immunity against the mouse mammary tumour virus : immunologic events during tumour growth and studies on vaccination in mice

    NARCIS (Netherlands)

    P.C. Creemers (Paula)

    1978-01-01

    textabstractDevelopment of mouse mammary tumours is a complex phenomenon, to which environmental factors, genetic background and the presence of an oncovirus contribute. The mammary tumour virus (MTV) of the mouse, first discovered by Bittner (1936), is a so-called B-type particle (Bernhard, 1958) a

  4. Cooling of heat-stressed cows during the dry period alters lymphocyte but not mammary gland gene expression

    Science.gov (United States)

    Heat stress (HT) during the dry period compromises mammary gland development, decreases future milk production, and impairs immune status of dairy cows. Our objective was to evaluate the effects of cooling heat-stressed cows during the dry period on gene expression of the mammary gland and lymphocyt...

  5. Pten in the Breast Tumor Microenvironment: Modeling Tumor-Stroma Co-Evolution

    Science.gov (United States)

    Wallace, Julie A.; Li, Fu; Leone, Gustavo; Ostrowski, Michael C.

    2010-01-01

    Solid human tumors and their surrounding microenvironment are hypothesized to co-evolve in a manner that promotes tumor growth, invasiveness and spread. Mouse models of cancer have focused on genetic changes in the epithelial tumor cells and therefore have not robustly tested this hypothesis. We have recently developed a murine breast cancer model that ablates the PTEN tumor suppressor pathway in stromal fibroblasts. Remarkably, the model resembles human breast tumors both at morphologic and molecular levels. We propose that such models reflect subtypes of tumor-stromal co-evolution relevant to human breast cancer, and will therefore be useful in defining the mechanisms that underpin tumor-stroma crosstalk. Additionally, these models should also aid in molecularly classifying human breast tumors based on both the microenvironment subtypes they contain as well as on the tumor subtype. PMID:21303970

  6. Morphogenesis of Mammary Glands in Buffalo (Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    Amit Challana

    2014-01-01

    Full Text Available The present research was elucidated on the morphogenesis of mammary gland of buffalo during prenatal development. Total of 16 foetuses ranging from 1.2 cm (34 days to 108 cm CVRL (curved crown rump length (317 days were used for study. The study revealed that mammary line was first observed at 1.2 cm CVRL (34 days, mammary hillock at 1.7 cm (37 days, and mammary bud at 2.6 cm CVRL (41 days foetuses. Epidermal cone was found at 6.7 cm CVRL (58 days whereas primary and secondary ducts were observed at 7.4 cm CVRL (62 days and 15 cm CVRL (96 days, respectively. Connective tissue whorls were reported at 18.2 cm CVRL (110 days and internal elastic lamina and muscle layers at 24.1 cm CVRL (129 days. Lobules were observed at 29.3 cm CVRL (140 days, rosette of furstenberg at 39.5 cm CVRL (163 days, and keratin plug at 45.5 cm CVRL (176 days foetus. Primordia of sweat and sebaceous glands around hair follicle were seen at 21.2 cm CVRL (122 days of foetal life. Differentiation of all the skin layers along with cornification was observed at 69 cm (229 days in group III foetuses.

  7. From genes to milk: genomic organization and epigenetic regulation of the mammary transcriptome.

    Science.gov (United States)

    Lemay, Danielle G; Pollard, Katherine S; Martin, William F; Freeman Zadrowski, Courtneay; Hernandez, Joseph; Korf, Ian; German, J Bruce; Rijnkels, Monique

    2013-01-01

    Even in genomes lacking operons, a gene's position in the genome influences its potential for expression. The mechanisms by which adjacent genes are co-expressed are still not completely understood. Using lactation and the mammary gland as a model system, we explore the hypothesis that chromatin state contributes to the co-regulation of gene neighborhoods. The mammary gland represents a unique evolutionary model, due to its recent appearance, in the context of vertebrate genomes. An understanding of how the mammary gland is regulated to produce milk is also of biomedical and agricultural importance for human lactation and dairying. Here, we integrate epigenomic and transcriptomic data to develop a comprehensive regulatory model. Neighborhoods of mammary-expressed genes were determined using expression data derived from pregnant and lactating mice and a neighborhood scoring tool, G-NEST. Regions of open and closed chromatin were identified by ChIP-Seq of histone modifications H3K36me3, H3K4me2, and H3K27me3 in the mouse mammary gland and liver tissue during lactation. We found that neighborhoods of genes in regions of uniquely active chromatin in the lactating mammary gland, compared with liver tissue, were extremely rare. Rather, genes in most neighborhoods were suppressed during lactation as reflected in their expression levels and their location in regions of silenced chromatin. Chromatin silencing was largely shared between the liver and mammary gland during lactation, and what distinguished the mammary gland was mainly a small tissue-specific repertoire of isolated, expressed genes. These findings suggest that an advantage of the neighborhood organization is in the collective repression of groups of genes via a shared mechanism of chromatin repression. Genes essential to the mammary gland's uniqueness are isolated from neighbors, and likely have less tolerance for variation in expression, properties they share with genes responsible for an organism's survival.

  8. Phyllodes tumor of the breast: role of Axl and ST6GalNAcII in the development of mammary phyllodes tumors.

    Science.gov (United States)

    Ren, Dongliang; Li, Yanyan; Gong, Yanxin; Xu, Jingchao; Miao, Xiaolong; Li, Xiangnan; Liu, Chen; Jia, Li; Zhao, Yongfu

    2014-10-01

    Phyllodes tumor exhibits an aggressive growth. The expression of many biological markers has been explored to discriminate between different grades of phyllodes tumor and to predict their behavior. The purpose of this study was to evaluate the implications of Axl and ST6GalNAcII in phyllodes tumors. Real-time PCR, Western blot, and immunohistochemical were used to analyze differential expression of ST6GalNAcII and Axl in phyllodes tumor (PT) cell lines and tissue specimens. RNAi assay, ECM invasion assay, and tumorigenicity assay were used to analyze the altered expression of ST6GalNAcII gene effects on the expression of Axl and invasive ability of phyllodes tumor cells in vitro and in vivo. Compared to benign tumors, borderline and malignant ones showed a remarkable increase in mRNA levels of Axl and ST6GalNAcII gene, and it was higher in malignant tumor cells than in borderline tumor cells. When ST6GalNAcII was silenced, compared to the control, the expression level of Axl was significantly reduced in malignant tumor cell transfectants and knockdown of ST6GalNAcII gene significantly inhibited invasive activity in malignant tumor cells. The high expression of ST6GalNAcII and Axl was significantly correlated with tumor grade and distance metastasis by immunohistochemical analysis. Axl and ST6GalNAcII expression increases with increasing tumor grade in mammary phyllodes tumors. ST6GalNAc II might be participated in the glycosylation of Axl, and this Axl glycosylation may mediate the tumorigenicity, invasion, and distant metastasis of PT cells.

  9. The Type 7 Serotonin Receptor, 5-HT7, Is Essential in the Mammary Gland for Regulation of Mammary Epithelial Structure and Function

    Directory of Open Access Journals (Sweden)

    Vaibhav P. Pai

    2015-01-01

    Full Text Available Autocrine-paracrine activity of serotonin (5-hydroxytryptamine, 5-HT is a crucial homeostatic parameter in mammary gland development during lactation and involution. Published studies suggested that the 5-HT7 receptor type was important for mediating several effects of 5-HT in the mammary epithelium. Here, using 5-HT7 receptor-null (HT7KO mice we attempt to understand the role of this receptor in mediating 5-HT actions within the mammary gland. We demonstrate for the first time that HT7KO dams are inefficient at sustaining their pups. Histologically, the HT7KO mammary epithelium shows a significant deviation from the normal secretory epithelium in morphological architecture, reduced secretory vesicles, and numerous multinucleated epithelial cells with atypically displaced nuclei, during lactation. Mammary epithelial cells in HT7KO dams also display an inability to transition from lactation to involution as normally seen by transition from a columnar to a squamous cell configuration, along with alveolar cell apoptosis and cell shedding. Our results show that 5-HT7 is required for multiple actions of 5-HT in the mammary glands including core functions that contribute to changes in cell shape and cell turnover, as well as specialized secretory functions. Understanding these actions may provide new interventions to improve lactation performance and treat diseases such as mastitis and breast cancer.

  10. The Type 7 Serotonin Receptor, 5-HT7, Is Essential in the Mammary Gland for Regulation of Mammary Epithelial Structure and Function

    Science.gov (United States)

    Pai, Vaibhav P.; Hernandez, Laura L.; Stull, Malinda A.; Horseman, Nelson D.

    2015-01-01

    Autocrine-paracrine activity of serotonin (5-hydroxytryptamine, 5-HT) is a crucial homeostatic parameter in mammary gland development during lactation and involution. Published studies suggested that the 5-HT7 receptor type was important for mediating several effects of 5-HT in the mammary epithelium. Here, using 5-HT7 receptor-null (HT7KO) mice we attempt to understand the role of this receptor in mediating 5-HT actions within the mammary gland. We demonstrate for the first time that HT7KO dams are inefficient at sustaining their pups. Histologically, the HT7KO mammary epithelium shows a significant deviation from the normal secretory epithelium in morphological architecture, reduced secretory vesicles, and numerous multinucleated epithelial cells with atypically displaced nuclei, during lactation. Mammary epithelial cells in HT7KO dams also display an inability to transition from lactation to involution as normally seen by transition from a columnar to a squamous cell configuration, along with alveolar cell apoptosis and cell shedding. Our results show that 5-HT7 is required for multiple actions of 5-HT in the mammary glands including core functions that contribute to changes in cell shape and cell turnover, as well as specialized secretory functions. Understanding these actions may provide new interventions to improve lactation performance and treat diseases such as mastitis and breast cancer. PMID:25664318

  11. Prepubertal exposure to cow's milk reduces susceptibility to carcinogen-induced mammary tumorigenesis in rats

    DEFF Research Database (Denmark)

    Nielsen, Tina Skau; Khan, Galam; Davis, Jennifer

    2011-01-01

    Cow's milk contains high levels of estrogens, progesterone and insulin-like growth factor 1 (IGF-1), all of which are associated with breast cancer. We investigated whether prepubertal milk exposure affects mammary gland development and carcinogenesis in rats. Sprague-Dawley rats were given either...... whole milk or tap water to drink from postnatal day (PND) 14 to PND 35, and thereafter normal tap water. Mammary tumorigenesis was induced by administering 7,12-dimethylbenz[a]anthracene on PND 50. Milk exposure increased circulating E2 levels on PND 25 by 10-fold (p vaginal...... or apoptosis were seen. IGF-1 mRNA levels were reduced on PND 50 in the mammary glands of rats exposed to milk at puberty. Our results suggest that drinking milk before puberty reduces later risk of developing mammary cancer in rats. This might be mediated by a reduction in the number of TEBs and lower...

  12. Immunohistochemical expression of PTEN in normal, hyperplastic and endometrial carcinoma of endometrium

    Directory of Open Access Journals (Sweden)

    IzadiMood

    2008-08-01

    Full Text Available "nBackground: Endometrial carcinoma is the most common malignancy of the female genital tract. Different molecular alterations have been described in endometrioid endometrial carcinoma that, the most frequently altered gene is mutations of PTEN. Up to 50-83% of endometrioid carcinoma reveal altered PTEN characterized by loss of expression. In endometrial hyperplasia, which are precursors of endometrioid carcinoma, loss of PTEN expression is 30-63%."n"nMethods: Immunohistochemical staining was performed on 90 cases of endometrial curettage including: 30 proliferative endometrium, 30 hyperplastic endometrium and 30 endometroid carcinoma."n"nImmunohistochemical specimens were graded semiquatitatively by considering the percentage of staining with two cut-point 10% & 50% on the whole section for each specimen."n"nResults: loss of PTEN expression was observed 0%, 0%, 30% of 51.7% in proliferative, simple hyperplasia, complex hyperplasia and endometrioid carcinoma respectively with cut-point 10% and 0%, 5.3%, 30%, 52.2% in endometrioid carcinoma respectively with cut-point 50%. Also there was no difference in PTEN expression between atypical complex hyperplasia and endometrioid carcinoma but there was significant difference between simple hyperplasia and proliferative with endometrioid carcinoma & atypical complex hyperplasia."n"nConclusion: These results show loss of PTEN expression in endmetrioid carcinoma and no differences between endometrioid carcinoma and atypical complex hyperplasia. Therefore, assessment of PTEN expression by negative immunostaining and matched with routine hematoxylin and eosin stained can be a new tool for diagnosis of endometrioid carcinoma.

  13. Breast cancer risk and clinical implications for germline PTEN mutation carriers.

    Science.gov (United States)

    Ngeow, Joanne; Sesock, Kaitlin; Eng, Charis

    2017-08-01

    PTEN Hamartoma Tumor syndrome (PHTS) encompasses a clinical spectrum of heritable disorders including Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome, and Proteus and Proteus-like syndrome that are associated with germline mutations in the PTEN tumor suppressor gene. Breast cancer risk estimates (67-85 %) for women with germline PTEN mutations are similar to those quoted for patients with germline mutations in the BRCA1/2 genes. With PTEN on several germline gene testing panels, finding PTEN mutations and variants have increased exponentially. PHTS can be differentiated from other hereditary cancer syndromes including Hereditary Breast Ovarian Cancer syndrome, Lynch syndrome, and hamartomatous polyposis syndromes based on personal as well as family history. However, many of the benign features of CS are common in the general population, making the diagnosis of CS challenging. Breast cancer patients with an identified germline PTEN mutation are at increased risk of endometrial, thyroid, renal, and colorectal cancers as well as a second breast cancer. Increased screening for the various component cancers as well as predictive testing in first-degree relatives is recommended. Prophylactic mastectomy may be considered especially if breast tissue is dense or if repeated breast biopsies have been necessary. Management of women with breast cancer suspected of CS who test negative for germline PTEN mutations should be managed as per a mutation carrier if she meets CS diagnostic criteria, and should be offered enrollment in research to identify other predisposition genes.

  14. PTEN alterations of the stromal cells characterise an aggressive subpopulation of pancreatic cancer with enhanced metastatic potential.

    Science.gov (United States)

    Wartenberg, Martin; Centeno, Irene; Haemmig, Stefan; Vassella, Erik; Zlobec, Inti; Galván, José A; Neuenschwander, Maja; Schlup, Cornelia; Gloor, Beat; Lugli, Alessandro; Perren, Aurel; Karamitopoulou, Eva

    2016-09-01

    Neoplastic stroma is believed to influence tumour progression. Here, we examine phosphatase and tensin homolog deleted on chromosome ten (PTEN) status in the tumour microenvironment of pancreatic ductal adenocarcinoma (PDAC) focussing especially at the stromal cells. We asses PTEN at protein, messenger RNA and DNA level using a well-characterised PDAC cohort (n = 117). miR-21, known to target PTEN, is assessed after RNA extraction from different laser-capture-microdissected cell populations, including cancer cells and juxta-tumoural and tumour-remote stroma. PTEN deletion was the most frequent cause of PTEN protein loss in PDAC cells (71%) and correlated with vascular invasion (p = 0.0176) and decreased overall survival (p = 0.0127). Concomitant PTEN protein loss in tumour and juxta-tumoural stroma, found in 21.4% of PDACs, correlated with increased distant metastasis (p = 0.0045). Stromal cells with PTEN protein loss frequently showed PTEN genetic aberrations, including hemizygous PTEN deletion (46.6%) or chromosome 10 monosomy (40%). No alterations were found in the tumour-remote stroma. miR-21 was overexpressed by cancer- and juxta-tumoural stromal cells, in some cases without simultaneous PTEN gene alterations. No PTEN mutations or promoter methylation were detected. We find various mechanisms of PTEN protein loss in the different tumour cell populations, including allelic PTEN deletions, gross chromosomal 10 aberrations and altered miR-21 expression. PTEN deletion is a major cause of PTEN protein loss in PDAC and correlates with aggressive characteristics and worse outcome. PTEN protein loss in juxta-tumoural stromal cells is mostly due to PTEN haplo-insufficiency and characterises a subgroup of PDACs with enhanced metastatic potential. In the tumour microenvironment of the invasive front, PTEN silencing by miR-21 in cancer and surrounding stromal cells acts not only cooperatively but also independently of the genetic aberrations to precipitate PTEN

  15. Posttranslational regulation of phosphatase and tensin homolog (PTEN and its functional impact on cancer behaviors

    Directory of Open Access Journals (Sweden)

    Xu WT

    2014-10-01

    Full Text Available Wenting Xu,1 Zhen Yang,1 Shu-Feng Zhou,2 Nonghua Lu1 1Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China; 2Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA Abstract: The incidence of cancer is increasing worldwide, but the biochemical mechanisms for the occurrence of cancer is not fully understood, and there is no cure for advanced tumors. Defects of posttranslational modifications of proteins are linked to a number of important diseases, such as cancer. This review will update our knowledge on the critical role of posttranscriptional regulation of phosphatase and tensin homolog (PTEN and its activities and the functional impact on cancer behaviors. PTEN is a tumor suppressor gene that occupies a key position in regulating cell growth, proliferation, apoptosis, mobility, signal transduction, and other crucial cellular processes. The activity and function of PTEN are regulated by coordinated epigenetic, transcriptional, posttranscriptional, and posttranslational modifications. In particular, PTEN is subject to phosphorylation, ubiquitylation, somoylation, acetylation, and active site oxidation. Posttranslational modifications of PTEN can dynamically change its activity and function. Deficiency in the posttranslational regulation of PTEN leads to abnormal cell proliferation, apoptosis, migration, and adhesion, which are associated with cancer initiation, progression, and metastasis. With increasing information on how PTEN is regulated by multiple mechanisms and networked proteins, its exact role in cancer initiation, growth, and metastasis will be revealed. PTEN and its functionally related proteins may represent useful targets for the discovery of new anticancer drugs, and gene therapy and the therapeutic potentials should be fully explored. Keywords: phosphorylation, ubiquitination, acetylation, oxidation

  16. Endogenous S-sulfhydration of PTEN helps protect against modification by nitric oxide

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Kazuki; Okuda, Kosaku; Uehara, Takashi, E-mail: uehara@pharm.okayama-u.ac.jp

    2015-01-02

    Highlights: • PTEN is S-sulfhydrated endogenously in SH-SY5Y human neuroblastoma cells. • Preventing this modification by knocking down CBS renders PTEN sensitive to NO. • pAkt levels are increased significantly in CBS siRNA-transfected cells. • H{sub 2}S functions as an endogenous regulator of PTEN in neuronal cells. - Abstract: Hydrogen sulfide (H{sub 2}S) is a gaseous regulatory factor produced by several enzymes, and plays a pivotal role in processes such as proliferation or vasodilation. Recent reports demonstrated the physiological and pathophysiological functions of H{sub 2}S in neurons. PTEN is a target of nitric oxide (NO) or hydrogen peroxide, and the oxidative modification of cysteine (Cys) residue(s) attenuates its enzymatic activity. In the present study, we assessed the effect of H{sub 2}S on the direct modification of PTEN and the resulting downstream signaling. A modified biotin switch assay in SH-SY5Y human neuroblastoma cells revealed that PTEN is S-sulfhydrated endogenously. Subsequently, site-directed mutagenesis demonstrated that both Cys71 and Cys124 in PTEN are targets for S-sulfhydration. Further, the knockdown of cystathionine β-synthetase (CBS) using siRNA decreased this modification in a manner that was correlated to amount of H{sub 2}S. PTEN was more sensitive to NO under these conditions. These results suggest that the endogenous S-sulfhydration of PTEN via CBS/H{sub 2}S plays a role in preventing the S-nitrosylation that would inhibition its enzymatic activity under physiological conditions.

  17. The significance of PTEN and AKT aberrations in pediatric T-cell acute lymphoblastic leukemia

    Science.gov (United States)

    Zuurbier, Linda; Petricoin, Emanuel F.; Vuerhard, Maartje J.; Calvert, Valerie; Kooi, Clarissa; Buijs-Gladdines, Jessica G.C.A.M.; Smits, Willem K.; Sonneveld, Edwin; Veerman, Anjo J.P.; Kamps, Willem A.; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2012-01-01

    Background PI3K/AKT pathway mutations are found in T-cell acute lymphoblastic leukemia, but their overall impact and associations with other genetic aberrations is unknown. PTEN mutations have been proposed as secondary mutations that follow NOTCH1-activating mutations and cause cellular resistance to γ-secretase inhibitors. Design and Methods The impact of PTEN, PI3K and AKT aberrations was studied in a genetically well-characterized pediatric T-cell leukemia patient cohort (n=146) treated on DCOG or COALL protocols. Results PTEN and AKT E17K aberrations were detected in 13% and 2% of patients, respectively. Defective PTEN-splicing was identified in incidental cases. Patients without PTEN protein but lacking exon-, splice-, promoter mutations or promoter hypermethylation were present. PTEN/AKT mutations were especially abundant in TAL- or LMO-rearranged leukemia but nearly absent in TLX3-rearranged patients (P=0.03), the opposite to that observed for NOTCH1-activating mutations. Most PTEN/AKT mutant patients either lacked NOTCH1-activating mutations (P=0.006) or had weak NOTCH1-activating mutations (P=0.011), and consequently expressed low intracellular NOTCH1, cMYC and MUSASHI levels. T-cell leukemia patients without PTEN/AKT and NOTCH1-activating mutations fared well, with a cumulative incidence of relapse of only 8% versus 35% for PTEN/AKT and/or NOTCH1-activated patients (P=0.005). Conclusions PI3K/AKT pathway aberrations are present in 18% of pediatric T-cell acute lymphoblastic leukemia patients. Absence of strong NOTCH1-activating mutations in these cases may explain cellular insensitivity to γ-secretase inhibitors. PMID:22491738

  18. Interaction of IGF2 and PTEN in ( M alignant Breast T issues

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    Preetha J Shetty

    2012-07-01

    Full Text Available Background: Breast Cancer (BC is one of the leading malignancies affecting women worldwide. Epigenetic mechanisms regulate gene expression playing an important role in the pathophysiology of cancer. In the present study IGF2 and PTEN genes in AKT pathway were selected for evaluation. Objective: To investigate the role of methylation and interaction of IGF2 and PTEN and in the pathoetiology of BC. Methods: Paraffin embedded archival breast tumor and adjacent normal tissue samples were used for carrying out PCR based methylation assay, genomic PCR, immunohistochemistry and qRT PCR. Results: In-Silico study indicated the absence of hormone responsive elements in the promoters of the selected genes. Methylation results indicated significant loss of methylation in IGF2 exon 9 CpG cluster and significant gain of PTEN promoter methylation in tumors. Immunohistochemistry revealed enhanced cytoplasmic expression o f IGF2 protein (p< 0.0001 and decreased nuclear localization of PTEN protein (p=0.0069 in the breast tumors. RT-PCR results indicated an increased IGF2 (p=0.024 and decreased PTEN transcripts (p<0.0001 in the tumors. Conclusion: Increased IGF2 in normal tissues increases PTEN which acts as a negative regulator of AKT pathway in the cytoplasm controlling excessive proliferation while in tumors this regulation is lost. PTEN acts as a negative regulator of MAPK pathway in the nucleus, plays an important role in cell cycle arrest in normal breast tissue. Reduction of PTEN in tumor tissue affects this pathway leading to cell survival. IGF2 and PTEN have a role in breast cancer and these molecular factors can be used for targeting therapy in future.

  19. Reversible fibroadenomatous mammary hyperplasia in male and female New Zealand white rabbits associated with cyclosporine A administration.

    Science.gov (United States)

    Krimer, P M; Harvey, S B; Blas-Machado, U; Lauderdale, J D; Moore, P A

    2009-11-01

    All male and female New Zealand white rabbits in a limbal cell graft study developed marked generalized mammary gland hypertrophy. Postprocedural medications included ophthalmic 0.1% dexamethasone, ophthalmic 0.5% cyclosporine, and subcutaneous cyclosporine A. Cytologic examination revealed epithelial clusters with minimal malignant criteria. On histologic evaluation, there was diffuse glandular hyperplasia with mild cellular atypia and ductal ectasia separated by abundant hypercellular fibrous stroma, consistent with fibroadenomatous mammary gland hyperplasia. The hyperplasia resolved within 2 weeks of cessation of cyclosporine, and at necropsy identifiable mammary masses were not found. Very little has been reported about the use of cyclosporine in laboratory rabbits and its association with development of mammary gland hyperplasia. This is the first report in which administration of cyclosporine to male and female rabbits at a dose as low as 5 mg/kg/day induced benign fibroadenomatous mammary gland hyperplasia. This change regressed after cessation of the drug.

  20. Chemoprevention of Radiation Induced Rat Mammary Neoplasms

    Science.gov (United States)

    Huso, David L.

    1999-01-01

    Radiations encountered in space include protons and heavy ions such as iron as well as their secondaries. The relative biological effect (RBE) of these ions is not known, particularly at the doses and dose-rates expected for planetary missions. Neutrons, are not particularly relevant to space travel, but have been found experimentally to have an increase in their RBE with decreasing dose. If a similar trend of increasing RBE with decreasing dose is present for heavy ions and protons during irradiation in space, the small doses received during space travel could potentially have substantial carcinogenic risk. Clearly more investigation of the effects of heavy ions and protons is needed before accurate risk assessment for prolonged travel in space can be done. One means to mitigate the increased risk of cancer due to radiation exposure in space is by developing effective countermeasures that can reduce the incidence of tumor development. Tamoxifen has recently been shown to be an effective chemopreventive agent in both animal models and humans for the prevention of mammary tumors. Tamoxifen is a unique drug, with a highly specific mechanism of action affecting a specific radiation-sensitive population of epithelial cells in the mammary gland. In human studies, the annual incidence of a primary tumor in the contralateral breast of women with previous breast cancer is about 8 per 1000, making them an exceedingly high-risk group for the development of breast cancer. In this high risk group, treated with tamoxifen, daily, for 2 years, the incidence of a new primary tumor in the contralateral breast was approximately one third of that noted in the non-tamoxifen treatment group. Tamoxifen antagonizes the action of estrogen by competing for the nuclear receptor complex thereby altering the association of the receptor complex and nuclear binding sites. Its effects in reducing the development of breast cancer could be accomplished by controlling clinically undetectable

  1. Chemoprevention of Radiation Induced Rat Mammary Neoplasms

    Science.gov (United States)

    Huso, David L.

    1999-01-01

    Radiations encountered in space include protons and heavy ions such as iron as well as their secondaries. The relative biological effect (RBE) of these ions is not known, particularly at the doses and dose-rates expected for planetary missions. Neutrons, are not particularly relevant to space travel, but have been found experimentally to have an increase in their RBE with decreasing dose. If a similar trend of increasing RBE with decreasing dose is present for heavy ions and protons during irradiation in space, the small doses received during space travel could potentially have substantial carcinogenic risk. Clearly more investigation of the effects of heavy ions and protons is needed before accurate risk assessment for prolonged travel in space can be done. One means to mitigate the increased risk of cancer due to radiation exposure in space is by developing effective countermeasures that can reduce the incidence of tumor development. Tamoxifen has recently been shown to be an effective chemopreventive agent in both animal models and humans for the prevention of mammary tumors. Tamoxifen is a unique drug, with a highly specific mechanism of action affecting a specific radiation-sensitive population of epithelial cells in the mammary gland. In human studies, the annual incidence of a primary tumor in the contralateral breast of women with previous breast cancer is about 8 per 1000, making them an exceedingly high-risk group for the development of breast cancer. In this high risk group, treated with tamoxifen, daily, for 2 years, the incidence of a new primary tumor in the contralateral breast was approximately one third of that noted in the non-tamoxifen treatment group. Tamoxifen antagonizes the action of estrogen by competing for the nuclear receptor complex thereby altering the association of the receptor complex and nuclear binding sites. Its effects in reducing the development of breast cancer could be accomplished by controlling clinically undetectable

  2. Internal Mammary Recipient Site Breast Cancer Recurrence Following Delayed Microvascular Breast Reconstruction

    OpenAIRE

    Rosich-Medina, Anais; Wang, Susan; Erel, Ertan; Malata, Charles M.

    2013-01-01

    Objective: The internal mammary vessels are a popular recipient site for microsurgical anastomoses of free flap breast reconstructions. We, however, observed 3 patients undergoing internal mammary vessel delayed free flap breast reconstruction that subsequently developed tumor recurrence at this site. We reviewed their characteristics to determine whether there was a correlation between delayed microsurgical reconstruction and local recurrence. Methods: A retrospective review of a single surg...

  3. PTEN与Survivin在人皮肤血管瘤组织中的表达及意义%Significance and Expression of PTEN and Survivin in Human Dermal Hemangioma

    Institute of Scientific and Technical Information of China (English)

    蒋晖; 汪晓庆; 张端莲; 陕声国; 吴慧芬; 蔡丽华; 袁玉虎

    2009-01-01

    目的 探讨PTEN与Survivin在血管瘤发生、发展过程中的表达及意义.方法 应用免疫组织化学方法和RT-PCR法检测了皮肤血管瘤增生期、退化期以及正常皮肤组织中PTEN和Survivin的表达水平.结果 ①免疫组织化学结果:PTEN在增生期血管瘤内皮细胞的表达低于退化期,差异有显著性意义(P0.05).②RT-PCR结果:在退化期血管瘤和正常皮肤组织中均有明显的PTEN mRNA表达,而增生期血管瘤中PTEN mRNA的表达较弱;在增生期血管瘤中有明显的Survivin mRNA表达,而退化期血管瘤和正常皮肤组织中Survivin mRNA均无表达.结论 PTEN和Survivin参与了血管瘤的发生、发展和退化,PTEN通过诱导内皮细胞凋亡而促进血管瘤由增生向退化的转变,Survivin通过抑制内皮细胞凋亡而促进血管瘤的增生,两者在血管瘤的发生发展中发挥协同效应.%Objective To study the expression of PTEN and Survivin,and investigate the mechanism and significance of them in different phases of human hemangiomas. Methods The expression of PTEN and Survivin was detected by using immu-no-histochemical technique,and that of PTEN mRNA and Survivin mRNA by using reverse transcription polymerase chain reac-tion(RT-PCR)in proliferating,involuting human hemangiomas and normal skin tissues. Results ①The expression of PTEN in the endothelial cells of involuting hemangiomas was significantly higher than in proliferating hemangiomas(P0. 05). ②The expression of PTEN mRNA was strong in involting hemangiomas and normal skin tissues, but weak in proliferating hemangiomas. The expression of Survivin mRNA was significantly increased in proliferating hemangiomas,and no Survivin mRNA was detected in involuting hemangiomas and normal skin tissues. Conclusion It is suggested that both PTEN and Survivin may take part in the genesis,development,and involution. PTEN promoted the switching from proliferation to involution in hemangiomas through inducing the

  4. Metformin inhibits inflammatory response via AMPK-PTEN pathway in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Ae [Department of Pharmacology, Aging-Associated Vascular Disease Research Center, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, Aging-Associated Vascular Disease Research Center, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer PTEN was induced by metformin and inhibited by compound C and AMPK siRNA. Black-Right-Pointing-Pointer Metformin suppressed TNF-{alpha}-induced COX-2 and iNOS mRNA expression. Black-Right-Pointing-Pointer Compound C and bpv (pic) increased iNOS and COX-2 protein expression. Black-Right-Pointing-Pointer NF-{kappa}B activation was restored by inhibiting AMPK and PTEN. Black-Right-Pointing-Pointer AMPK and PTEN regulated TNF-{alpha}-induced ROS production in VSMCs. -- Abstract: Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), a key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK-PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2 mM) and inhibited by compound C (10 {mu}M) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-{alpha}) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-{kappa}B. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-{kappa}B activation decreased in response to metformin and was restored by inhibiting AMPK

  5. Pten Regulates Retinal Amacrine Cell Number by Modulating Akt, Tgfβ, and Erk Signaling.

    Science.gov (United States)

    Tachibana, Nobuhiko; Cantrup, Robert; Dixit, Rajiv; Touahri, Yacine; Kaushik, Gaurav; Zinyk, Dawn; Daftarian, Narsis; Biernaskie, Jeff; McFarlane, Sarah; Schuurmans, Carol

    2016-09-07

    All tissues are genetically programmed to acquire an optimal size that is defined by total cell number and individual cellular dimensions. The retina contains stereotyped proportions of one glial and six neuronal cell types that are generated in overlapping waves. How multipotent retinal progenitors know when to switch from making one cell type to the next so that appropriate numbers of each cell type are generated is poorly understood. Pten is a phosphatase that controls progenitor cell proliferation and differentiation in several lineages. Here, using a conditional loss-of-function strategy, we found that Pten regulates retinal cell division and is required to produce the full complement of rod photoreceptors and amacrine cells in mouse. We focused on amacrine cell number control, identifying three downstream Pten effector pathways. First, phosphoinositide 3-kinase/Akt signaling is hyperactivated in Pten conditional knock-out (cKO) retinas, and misexpression of constitutively active Akt (Akt-CA) in retinal explants phenocopies the reduction in amacrine cell production observed in Pten cKOs. Second, Akt-CA activates Tgfβ signaling in retinal explants, which is a negative feedback pathway for amacrine cell production. Accordingly, Tgfβ signaling is elevated in Pten cKO retinas, and epistatic analyses placed Pten downstream of TgfβRII in amacrine cell number control. Finally, Pten regulates Raf/Mek/Erk signaling levels to promote the differentiation of all amacrine cell subtypes, which are each reduced in number in Pten cKOs. Pten is thus a positive regulator of amacrine cell production, acting via multiple downstream pathways, highlighting its diverse actions as a mediator of cell number control. Despite the importance of size for optimal organ function, how individual cell types are generated in correct proportions is poorly understood. There are several ways to control cell number, including readouts of organ function (e.g., secreted hormones reach functional

  6. Transcript profiling of Elf5+/- mammary glands during pregnancy identifies novel targets of Elf5.

    Directory of Open Access Journals (Sweden)

    Renee L Rogers

    Full Text Available BACKGROUND: Elf5, an epithelial specific Ets transcription factor, plays a crucial role in the pregnancy-associated development of the mouse mammary gland. Elf5(-/- embryos do not survive, however the Elf5(+/- mammary gland displays a severe pregnancy-associated developmental defect. While it is known that Elf5 is crucial for correct mammary development and lactation, the molecular mechanisms employed by Elf5 to exert its effects on the mammary gland are largely unknown. PRINCIPAL FINDINGS: Transcript profiling was used to investigate the transcriptional changes that occur as a result of Elf5 haploinsufficiency in the Elf5(+/- mouse model. We show that the development of the mouse Elf5(+/- mammary gland is delayed at a transcriptional and morphological level, due to the delayed increase in Elf5 protein in these glands. We also identify a number of potential Elf5 target genes, including Mucin 4, whose expression, is directly regulated by the binding of Elf5 to an Ets binding site within its promoter. CONCLUSION: We identify novel transcriptional targets of Elf5 and show that Muc4 is a direct target of Elf5, further elucidating the mechanisms through which Elf5 regulates proliferation and differentiation in the mammary gland.

  7. Antitumor activity of rapamycin in a Phase I trial for patients with recurrent PTEN-deficient glioblastoma.

    Directory of Open Access Journals (Sweden)

    Tim F Cloughesy

    2008-01-01

    Full Text Available BACKGROUND: There is much discussion in the cancer drug development community about how to incorporate molecular tools into early-stage clinical trials to assess target modulation, measure anti-tumor activity, and enrich the clinical trial population for patients who are more likely to benefit. Small, molecularly focused clinical studies offer the promise of the early definition of optimal biologic dose and patient population. METHODS AND FINDINGS: Based on preclinical evidence that phosphatase and tensin homolog deleted on Chromosome 10 (PTEN loss sensitizes tumors to the inhibition of mammalian target of rapamycin (mTOR, we conducted a proof-of-concept Phase I neoadjuvant trial of rapamycin in patients with recurrent glioblastoma, whose tumors lacked expression of the tumor suppressor PTEN. We aimed to assess the safety profile of daily rapamycin in patients with glioma, define the dose of rapamycin required for mTOR inhibition in tumor tissue, and evaluate the antiproliferative activity of rapamycin in PTEN-deficient glioblastoma. Although intratumoral rapamycin concentrations that were sufficient to inhibit mTOR in vitro were achieved in all patients, the magnitude of mTOR inhibition in tumor cells (measured by reduced ribosomal S6 protein phosphorylation varied substantially. Tumor cell proliferation (measured by Ki-67 staining was dramatically reduced in seven of 14 patients after 1 wk of rapamycin treatment and was associated with the magnitude of mTOR inhibition (p = 0.0047, Fisher exact test but not the intratumoral rapamycin concentration. Tumor cells harvested from the Ki-67 nonresponders retained sensitivity to rapamycin ex vivo, indicating that clinical resistance to biochemical mTOR inhibition was not cell-intrinsic. Rapamycin treatment led to Akt activation in seven patients, presumably due to loss of negative feedback, and this activation was associated with shorter time-to-progression during post-surgical maintenance rapamycin

  8. Mammary gland tumor formation in transgenic mice overexpressing stromelysin-1

    Energy Technology Data Exchange (ETDEWEB)

    Sympson, Carolyn J; Bissell, Mina J; Werb, Zena

    1995-06-01

    An intact basement membrane (BM) is essential for the proper function, differentiation and morphology of many epithelial cells. The disruption or loss of this BM occurs during normal development as well as in the disease state. To examine the importance of BM during mammary gland development in vivo, we generated transgenic mice that inappropriately express autoactivating isoforms of the matrix metalloproteinase stromelysin-1. The mammary glands from these mice are both functionally and morphologically altered throughout development. We have now documented a dramatic incidence of breast tumors in several independent lines of these mice. These data suggest that overexpression of stromelysin-1 and disruption of the BM may be a key step in the multi-step process of breast cancer.

  9. The interplay of matrix metalloproteinases, morphogens and growth factors is necessary for branching of mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Simian, M.; Harail, Y.; Navre, M.; Werb, Z.; Lochter, A.; Bissell, M.J.

    2002-03-06

    The mammary gland develops its adult form by a process referred to as branching morphogenesis. Many factors have been reported to affect this process. We have used cultured primary mammary epithelial organoids and mammary epithelial cell lines in three-dimensional collagen gels to elucidate which growth factors, matrix metalloproteinases (MMPs) and mammary morphogens interact in branching morphogenesis. Branching stimulated by stromal fibroblasts, epidermal growth factor, fibroblast growth factor 7, fibroblast growth factor 2 and hepatocyte growth factor was strongly reduced by inhibitors of MMPs, indicating the requirement of MMPs for three-dimensional growth involved in morphogenesis. Recombinant stromelysin 1/MMP-3 alone was sufficient to drive branching in the absence of growth factors in the organoids. Plasmin also stimulated branching; however, plasmin-dependent branching was abolished by both inhibitors of plasmin and MMPs, suggesting that plasmin activates MMPs. To differentiate between signals for proliferation and morphogenesis, we used a cloned mammary epithelial cell line that lacks epimorphin, an essential mammary morphogen. Both epimorphin and MMPs were required for morphogenesis, but neither was required for epithelial cell proliferation. These results provide direct evidence for a critical role of MMPs in branching in mammary epithelium and suggest that, in addition to epimorphin, MMP activity is a minimum requirement for branching morphogenesis in the mammary gland.

  10. The drug-resistance to gefitinib in PTEN low expression cancer cells is reversed by irradiation in vitro

    Directory of Open Access Journals (Sweden)

    Zhao Lu-Jun

    2009-09-01

    Full Text Available Abstract Background Despite of the recent success of EGFR inhibitory agents, the primary drug-resistant becomes a major challenge for EGFR inhibitor therapies. PTEN gene is an important positive regulatory factor for response to EGFR inhibitor therapy. Low-expression of PTEN is clearly one of the important reasons why tumor cells resisted to tyrosine kinase inhibitors. Methods To investigate the drug-resistance reversal to gefitinb and the mechanism in PTEN low expression cells which radiated with X-rays in vitro, We demonstrated that H-157 lung cancer cells (low-expression of PTEN but phospho-EGFR overexpressed tumor cells exposed to X-rays. The PTEN expressions and radiosensitizing effects of tyrosine kinase inhibitor before and after irradiation were observed. The cell-survival rates were evaluated by colony-forming assays. The cell apoptosis was investigated using FCM. The expressions of phospho-EGFR and PTEN were determined by Western blot analysis. Results The results showed that the PTEN expressions were significantly enhanced by X-rays. Moreover, the cell growth curve and survival curve were down-regulated in the gefitinib-treated groups after irradiation. Meanwhile, the radiation-induced apoptosis of tumor cells was increased by inhibition of the EGFR through up-regulation of PTEN. Conclusion These results suggested that PTEN gene is an important regulator on TKI inhibition, and the resistance to tyrosine kinase inhibitors might be reversed by irradiation in PTEN low expression cancer cells.

  11. The CD10 enzyme is a key player to identify and regulate human mammary stem cells.

    Science.gov (United States)

    Bachelard-Cascales, Elodie; Chapellier, Marion; Delay, Emmanuel; Pochon, Gaetan; Voeltzel, Thibault; Puisieux, Alain; Caron de Fromentel, Claude; Maguer-Satta, Véronique

    2010-06-01

    The major components of the mammary ductal tree are an inner layer of luminal cells, an outer layer of myoepithelial cells, and a basement membrane that separates the ducts from the underlying stroma. Cells in the outer layer express CD10, a zinc-dependent metalloprotease that regulates the growth of the ductal tree during mammary gland development. To define the steps in the human mammary lineage at which CD10 acts, we have developed an in vitro assay for human mammary lineage progression. We show that sorting for CD10 and EpCAM cleanly separates progenitors from differentiated luminal cells and that the CD10-high EpCAM-low population is enriched for early common progenitor and mammosphere-forming cells. We also show that sorting for CD10 enriches sphere-forming cells from other tissue types, suggesting that it may provide a simple tool to identify stem or progenitor populations in tissues for which lineage studies are not currently possible. We demonstrate that the protease activity of CD10 and the adhesion function of beta1-integrin are required to prevent differentiation of mammary progenitors. Taken together, our data suggest that integrin-mediated contact with the basement membrane and cleavage of signaling factors by CD10 are key elements in the niche that maintains the progenitor and stem cell pools in the mammary lineage.

  12. Internal Mammary Recipient Site Breast Cancer Recurrence Following Delayed Microvascular Breast Reconstruction

    Science.gov (United States)

    Rosich-Medina, Anais; Wang, Susan; Erel, Ertan; Malata, Charles M.

    2013-01-01

    Objective: The internal mammary vessels are a popular recipient site for microsurgical anastomoses of free flap breast reconstructions. We, however, observed 3 patients undergoing internal mammary vessel delayed free flap breast reconstruction that subsequently developed tumor recurrence at this site. We reviewed their characteristics to determine whether there was a correlation between delayed microsurgical reconstruction and local recurrence. Methods: A retrospective review of a single surgeon's delayed free flap breast reconstructions using the internal mammary vessels was conducted over a 7-year period to identify the time intervals between mastectomy and delayed breast reconstruction and between delayed breast reconstruction and recurrence. Results: Three patients developed local recurrence at the site of the microvascular anastomoses following delayed breast reconstruction. All patients had been disease-free following mastectomy. The median time interval between mastectomy and delayed breast reconstruction was 28 months (range = 20-120 months) while that between delayed breast reconstruction and local recurrence was 7 months (range = 4-10 months). Two patients died from metastatic disease, 36 and 72 months following their local recurrence. One patient remains alive 44 months after reconstruction. Conclusions: Local tumor recurrence at the internal mammary vessel dissection site following delayed breast reconstruction raises the question whether these 2 events may be related. Specifically, could internal mammary vessel dissection undertaken for delayed microsurgical reconstruction predispose to recurrence in the internal mammary lymph nodes? Further research is needed to ascertain whether delayed breast reconstruction increases the risk of local recurrence in this patient group. PMID:23383360

  13. Role of ERα in the differential response of Stat5a loss in susceptibility to mammary preneoplasia and DMBA-induced carcinogenesis

    OpenAIRE

    Miermont, Anne M.; Parrish, Angela R.; Furth, Priscilla A

    2010-01-01

    Deregulated estrogen signaling is evidently linked to breast cancer pathophysiology, although the role of signal transducer and activator of transcription (Stat)5a, integral to normal mammary gland development, is less clear. A mouse model of mammary epithelial cell-targeted deregulated estrogen receptor α (ERα) expression [conditional ERα in mammary epithelium (CERM)] was crossed with mice carrying a germ line deletion of Stat5a [Stat5a−/−] to investigate interactions between ERα and Stat5a ...

  14. The effects of antisense PTEN gene transfection on the growth and invasion of glioma cells

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong-jie; ZHENG Zhao-cong; WANG Ru-mi; WANG Shou-sen; YANG Wei-zhong

    2006-01-01

    Objective:To study the effects of antisense PTEN gene on the growth and invasion of glioma cells. Methods:A pcDNA3. 1/Hygro (-) recombinant plasmid containing antisense PTEN gene fragment was constructed. Glioma cells of primary culture were transfected with antisense PTEN gene vector and stably transfected clones were selected. Then, the different growth and invasion abilities and the different MMP9 mRNA expressions of three kinds of cells were observed, including the transfected cells, untransfected cells and the cells transfected with empty vector. Results :The abilities of growth and invasion of the transfected cells and the expressions of MMP9 mRNA were obviously enhanced. Conclusion: Antisense PTEN gene could have a negative impact on the growth and invasion of primary culture glioma cells.

  15. Tnactivation of PTEN is associated with increased angiogenesis and VEGF overexpression in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Ye-Jiang Zhou; Yu-Xia Xiong; Xiao-Ting Wu; De Shi; Wei Fan; Tong Zhou; Yue-Chun Li; Xiong Huang

    2004-01-01

    AIM: To investigate the expression of PTEN/MMAC1/TEP1and vascular endothelial growth factor (VEGF), their roles in biologic behavior and angiogenesis and their association in gastric cancer.METHODS: Immunohistochemical staining was used to evaluate the expression of PTEN, VEGF and microvascular density (MVD) on paraffin-embedded sections in 70 patients with primary gastric cancer and 24 patients with chronic superficial gastritis (CSG). Expression of PTEN, VEGF and MVD were compared with clinicopathological features of gastric cancer. The relationship between expression of PTEN, VEGF and MVD as well as the relationship between PTEN and VEGF expression in caner cells were investigated.RESULTS: PTEN expression significantly decreased (t= 3.98,P<0.01) whereas both VEGF expression and MVD significant increased (t = 4.29 and 4.41, respectively, both P<0.01)in gastric cancer group compared with CSG group. PTEN expression was significantly down-regulated (t = 1.95,P<0.05) whereas VEGF expression (t = 2.37, P<0.05) and MVD (t = 3.28, P<0.01) was significantly up-regulated in advanced gastric cancer compared with early-stage gastric cancer. PTEN expression in gastric cancer showed a negative association with lymph node metastasis (t= 3.91, P<0.01),invasion depth (t= 1.95, P<0.05) and age (t= 4.69, P<0.01).MVD in PTEN-negative gastric cancer was significantly higher than that in PTEN-positive gastric cancer (t = 3.69,P<0.01), and there was a negative correlation between PTEN expression and MVD (γ = -0.363, P<0.05). VEGF expression was positively associated with invasion depth (especially with serosa invasion, t = 4.69, P<0.01), lymph node metastasis (t= 2.31, P<0.05) and TNM stage (t= 3.04,P<0.01). MVD in VEGF-positive gastric cancer was significantly higher than that in VEGF-negative gastric cancer (t = 4.62,P<0.01), and there was a positive correlation between VEGF expression of and MVD (γ = 0.512, P<0.05). VEGF expression in PTEN

  16. Kaempferol Promotes Apoptosis in Human Bladder Cancer Cells by Inducing the Tumor Suppressor, PTEN

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    Liqun Zhou

    2013-10-01

    Full Text Available Kaempferol (Kae, a natural flavonoid, is widely distributed in fruits and vegetables. Previous studies have identified Kae as a possible cancer preventive and therapeutic agent. We found Kae to exhibit potent antiproliferation and anti-migration effects in human bladder cancer EJ cells. Kaempferol robustly induced apoptosis in EJ cells in a dose-dependent manner, as evidenced by increased cleavage of caspase-3. Furthermore, we found Kae-induced apoptosis in EJ cells to be associated with phosphatase and the tensin homolog deleted on the chromosome 10 (PTEN/PI3K/Akt pathway. Kae significantly increased PTEN and decreased Akt phosphorylation. Kae-induced apoptosis was partially attenuated in PTEN-knockdown cells. Our findings indicate that Kae could be an alternative medicine for bladder cancer, based on a PTEN activation mechanism.

  17. Skp2蛋白和PTEN蛋白在子宫内膜疾病中的表达及相关性研究%Expression of Skp2 protein and PTEN protein in endometrial cancer and their relationship

    Institute of Scientific and Technical Information of China (English)

    李美艳; 原丹丹; 李福琴; 赵琳琳

    2009-01-01

    Objective To investigate the expression of Skp2 and PTEN in endometrial tissues and their correlation and the carcinogenesis progression. Methods The expression of Skp2 and PTEN protein was detected by immunohistochemical methods in 42 cases of endometrial cancer, 35 cases of endometrial dys-plasia and 23 cases of endometrial hyperplasia complex and 15 cases of normal endometrium. The relation of Skp2 and PTEN protein was analyzed. Results The positive rate of Skp2 protein expression in endometrial cancer was significantly higher than that in endometrial dysplasia and endometrial hyperplasia complex and normal endometrium (P<0. 05). While the positive rate of PTEN was opposite to that of Skp2,the expression of PTEN was significantly lower than that in non-cancerous tissues (P <0. 05) In endometrial cancer,there was negative correlation between expression of Skp2 and PTEN. Conclusion Skp2 protein and PTEN protein play important roles in origination and development of endometrial cancer and the combination detection of Skp2 protein and PTEN protein expression may be helpful in predicting the malignant degree and prognosis of endometrial cancer.%目的 探讨Skp2和PTEN在子宫内膜组织中的表达及其在子宫内膜癌发生、发展过程中的作用及两者的关系.方法 采用免疫组织化SP法检测42例子宫内膜癌、35例子宫内膜不典型增生,23例复杂性增生及15例正常内膜中Skp2蛋白和PTEN蛋白的表达情况,并分析两者的相关性.结论 子宫内膜癌中Skp2蛋白表达水平显著高于正常子宫内膜、复杂增生及不典型增生的子官内膜,差异有显著性(P<0.05);PTEN蛋白的表达完全相反,且二者的表达呈负相关.结论Skp2蛋白和PTEN蛋白在子宫内膜癌的发生、发展中发挥重要作用,Skp2和PTEN的联合检测有助于判断子宫内膜癌的恶性程度和预后.

  18. PTEN phosphatase-independent maintenance of glandular morphology in a predictive colorectal cancer model system.

    Science.gov (United States)

    Jagan, Ishaan C; Deevi, Ravi K; Fatehullah, Aliya; Topley, Rebecca; Eves, Joshua; Stevenson, Michael; Loughrey, Maurice; Arthur, Kenneth; Campbell, Frederick Charles

    2013-11-01

    Organotypic models may provide mechanistic insight into colorectal cancer (CRC) morphology. Three-dimensional (3D) colorectal gland formation is regulated by phosphatase and tensin homologue deleted on chromosome 10 (PTEN) coupling of cell division cycle 42 (cdc42) to atypical protein kinase C (aPKC). This study investigated PTEN phosphatase-dependent and phosphatase-independent morphogenic functions in 3D models and assessed translational relevance in human studies. Isogenic PTEN-expressing or PTEN-deficient 3D colorectal cultures were used. In translational studies, apical aPKC activity readout was assessed against apical membrane (AM) orientation and gland morphology in 3D models and human CRC. We found that catalytically active or inactive PTEN constructs containing an intact C2 domain enhanced cdc42 activity, whereas mutants of the C2 domain calcium binding region 3 membrane-binding loop (M-CBR3) were ineffective. The isolated PTEN C2 domain (C2) accumulated in membrane fractions, but C2 M-CBR3 remained in cytosol. Transfection of C2 but not C2 M-CBR3 rescued defective AM orientation and 3D morphogenesis of PTEN-deficient Caco-2 cultures. The signal intensity of apical phospho-aPKC correlated with that of Na(+)/H(+) exchanger regulatory factor-1 (NHERF-1) in the 3D model. Apical NHERF-1 intensity thus provided readout of apical aPKC activity and associated with glandular morphology in the model system and human colon. Low apical NHERF-1 intensity in CRC associated with disruption of glandular architecture, high cancer grade, and metastatic dissemination. We conclude that the membrane-binding function of the catalytically inert PTEN C2 domain influences cdc42/aPKC-dependent AM dynamics and gland formation in a highly relevant 3D CRC morphogenesis model system.

  19. MicroRNA-21 regulates hTERT via PTEN in hypertrophic scar fibroblasts.

    Directory of Open Access Journals (Sweden)

    Hua-Yu Zhu

    Full Text Available BACKGROUND: As an important oncogenic miRNA, microRNA-21 (miR-21 is associated with various malignant diseases. However, the precise biological function of miR-21 and its molecular mechanism in hypertrophic scar fibroblast cells has not been fully elucidated. METHODOLOGY/PRINCIPAL FINDINGS: Quantitative Real-Time PCR (qRT-PCR analysis revealed significant upregulation of miR-21 in hypertrophic scar fibroblast cells compared with that in normal skin fibroblast cells. The effects of miR-21 were then assessed in MTT and apoptosis assays through in vitro transfection with a miR-21 mimic or inhibitor. Next, PTEN (phosphatase and tensin homologue deleted on chromosome ten was identified as a target gene of miR-21 in hypertrophic scar fibroblast cells. Furthermore, Western-blot and qRT-PCR analyses revealed that miR-21 increased the expression of human telomerase reverse transcriptase (hTERT via the PTEN/PI3K/AKT pathway. Introduction of PTEN cDNA led to a remarkable depletion of hTERT and PI3K/AKT at the protein level as well as inhibition of miR-21-induced proliferation. In addition, Western-blot and qRT-PCR analyses confirmed that hTERT was the downstream target of PTEN. Finally, miR-21 and PTEN RNA expression levels in hypertrophic scar tissue samples were examined. Immunohistochemistry assays revealed an inverse correlation between PTEN and hTERT levels in high miR-21 RNA expressing-hypertrophic scar tissues. CONCLUSIONS/SIGNIFICANCE: These data indicate that miR-21 regulates hTERT expression via the PTEN/PI3K/AKT signaling pathway by directly targeting PTEN, therefore controlling hypertrophic scar fibroblast cell growth. MiR-21 may be a potential novel molecular target for the treatment of hypertrophic scarring.

  20. PTEN Phosphatase-Independent Maintenance of Glandular Morphology in a Predictive Colorectal Cancer Model System

    Directory of Open Access Journals (Sweden)

    Ishaan C. Jagan

    2013-11-01

    Full Text Available Organotypic models may provide mechanistic insight into colorectal cancer (CRC morphology. Three-dimensional (3D colorectal gland formation is regulated by phosphatase and tensin homologue deleted on chromosome 10 (PTEN coupling of cell division cycle 42 (cdc42 to atypical protein kinase C (aPKC. This study investigated PTEN phosphatase-dependent and phosphatase-independent morphogenic functions in 3D models and assessed translational relevance in human studies. Isogenic PTEN-expressing or PTEN-deficient 3D colorectal cultures were used. In translational studies, apical aPKC activity readout was assessed against apical membrane (AM orientation and gland morphology in 3D models and human CRC. We found that catalytically active or inactive PTEN constructs containing an intact C2 domain enhanced cdc42 activity, whereas mutants of the C2 domain calcium binding region 3 membrane-binding loop (M-CBR3 were ineffective. The isolated PTEN C2 domain (C2 accumulated in membrane fractions, but C2 M-CBR3 remained in cytosol. Transfection of C2 but not C2 M-CBR3 rescued defective AM orientation and 3D morphogenesis of PTEN-deficient Caco-2 cultures. The signal intensity of apical phospho-aPKC correlated with that of Na+/H+ exchanger regulatory factor-1 (NHERF-1 in the 3D model. Apical NHERF-1 intensity thus provided readout of apical aPKC activity and associated with glandular morphology in the model system and human colon. Low apical NHERF-1 intensity in CRC associated with disruption of glandular architecture, high cancer grade, and metastatic dissemination. We conclude that the membrane-binding function of the catalytically inert PTEN C2 domain influences cdc42/aPKC-dependent AM dynamics and gland formation in a highly relevant 3D CRC morphogenesis model system.

  1. Radiogenic neoplasia in thyroid and mammary clonogens

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, K.H.

    1991-05-31

    We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. During the end of the last grant year and the first half of the current grant year, we have completed analyses and summarized for publication: investigations on the relationship between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamicpituitary axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH- (thyrotropin-) responsive sub-population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and the results of the large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. We are testing new techniques for the culture, cytofluorescent analysis and characterization mammary epithelial cells and of clonogens in a parallel project, and plan to apply similar technology to the thyroid epithelial cells and clonogen population. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cells interactions during the neoplastic process.

  2. Chronic social isolation is associated with metabolic gene expression changes specific to mammary adipose tissue.

    Science.gov (United States)

    Volden, Paul A; Wonder, Erin L; Skor, Maxwell N; Carmean, Christopher M; Patel, Feenalie N; Ye, Honggang; Kocherginsky, Masha; McClintock, Martha K; Brady, Matthew J; Conzen, Suzanne D

    2013-07-01

    Chronic social isolation is linked to increased mammary tumor growth in rodent models of breast cancer. In the C3(1)/SV40 T-antigen FVB/N (TAg) mouse model of "triple-negative" breast cancer, the heightened stress response elicited by social isolation has been associated with increased expression of metabolic genes in the mammary gland before invasive tumors develop (i.e., during the in situ carcinoma stage). To further understand the mechanisms underlying how accelerated mammary tumor growth is associated with social isolation, we separated the mammary gland adipose tissue from adjacent ductal epithelial cells and analyzed individual cell types for changes in metabolic gene expression. Specifically, increased expression of the key metabolic genes Acaca, Hk2, and Acly was found in the adipocyte, rather than the epithelial fraction. Surprisingly, metabolic gene expression was not significantly increased in visceral adipose depots of socially isolated female mice. As expected, increased metabolic gene expression in the mammary adipocytes of socially isolated mice coincided with increased glucose metabolism, lipid synthesis, and leptin secretion from this adipose depot. Furthermore, application of media that had been cultured with isolated mouse mammary adipose tissue (conditioned media) resulted in increased proliferation of mammary cancer cells relative to group-housed-conditioned media. These results suggest that exposure to a chronic stressor (social isolation) results in specific metabolic reprogramming in mammary gland adipocytes that in turn contributes to increased proliferation of adjacent preinvasive malignant epithelial cells. Metabolites and/or tumor growth-promoting proteins secreted from adipose tissue could identify biomarkers and/or targets for preventive intervention in breast cancer.

  3. Expression and function of heregulin-α and its receptors in the mouse mammary gland

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Heregulin-α (HRGα) is a cytokine secreted by the mammary mesenchyme, adjacent to lobuloalveolar structures. To understand the role of HRGα and its receptors in mammary glands, and the underlying mechanisms, we performed this study to determine the expression and localization of HRGα and its receptors ErbB2 and ErbB3. We also determined the role of HRGα in the development of mammary glands, β-casein expression and secretion, Rab3A protein expression and the phosphorylation of HRGα signaling molecules using confocal laser scanning microscopy, tissue culture, capillary electrophoresis, Western blotting and enzyme-linked immunosorbent assays. We found that a peak was on pregnancy day 15. Changes of ErbB2 and ErbB3 expression were positively and linearly correlated with HRGα, indicating that HRGα positively regulates ErbB2 and ErbB3 expression. During pregnancy, HRGα enhanced the phosphorylation of STAT5, p42/p44, p38, PKC and Rab3A protein expression, stimulated the proliferation and differentiation of the ductal epithelial cells of mammary glands, and increased and maintained the expression and secretion of β-casein. During lactation, HRGα enhanced the phosphorylation of STAT5 and p38, inhibited the phosphorylation of PKC and Rab3A protein expression, maintained the morphology of the mammary glands and increased the secretion of lactoprotein to reduce the expression of β-casein in mammary epithelial cells. During involution, HRGα induced the phosphorylation of STAT3 and Rab3A protein expression, and inhibited the phosphorylation of PKC to stimulate the degeneration of mammary epithelial cells. It also inhibited the secretion of β-casein, resulting in increased levels of β-casein in mammary epithelial cells.

  4. 4-Hydroxylation of estrogens as marker of human mammary tumors.

    OpenAIRE

    Liehr, J G; Ricci, M J

    1996-01-01

    Estrogen is a known risk factor in human breast cancer. In rodent models, estradiol has been shown to induce tumors in those tissues in which this hormone is predominantly converted to the catechol metabolite 4-hydroxyestradiol by a specific 4-hydroxylase enzyme, whereas tumors fail to develop in organs in which 2-hydroxylation predominates. We have now found that microsomes prepared from human mammary adenocarcinoma and fibroadenoma predominantly catalyze the metabolic 4-hydroxylation of est...

  5. Loss of the tumor suppressor Pten promotes proliferation of Drosophila melanogaster cells in vitro and gives rise to continuous cell lines.

    Science.gov (United States)

    Justiniano, Steven E; Mathew, Anne; Mitra, Sayan; Manivannan, Sathiya N; Simcox, Amanda

    2012-01-01

    In vivo analysis of Drosophila melanogaster has enhanced our understanding of many biological processes, notably the mechanisms of heredity and development. While in vivo analysis of mutants has been a strength of the field, analyzing fly cells in culture is valuable for cell biological, biochemical and whole genome approaches in which large numbers of homogeneous cells are required. An efficient genetic method to derive Drosophila cell lines using expression of an oncogenic form of Ras (Ras(V12)) has been developed. Mutations in tumor suppressors, which are known to cause cell hyperproliferation in vivo, could provide another method for generating Drosophila cell lines. Here we screened Drosophila tumor suppressor mutations to test if they promoted cell proliferation in vitro. We generated primary cultures and determined when patches of proliferating cells first emerged. These cells emerged on average at 37 days in wild-type cultures. Using this assay we found that a Pten mutation had a strong effect. Patches of proliferating cells appeared on average at 11 days and the cultures became confluent in about 3 weeks, which is similar to the timeframe for cultures expressing Ras(V12). Three Pten mutant cell lines were generated and these have now been cultured for between 250 and 630 cell doublings suggesting the life of the mutant cells is likely to be indefinite. We conclude that the use of Pten mutants is a powerful means to derive new Drosophila cell lines.

  6. Loss of the tumor suppressor Pten promotes proliferation of Drosophila melanogaster cells in vitro and gives rise to continuous cell lines.

    Directory of Open Access Journals (Sweden)

    Steven E Justiniano

    Full Text Available In vivo analysis of Drosophila melanogaster has enhanced our understanding of many biological processes, notably the mechanisms of heredity and development. While in vivo analysis of mutants has been a strength of the field, analyzing fly cells in culture is valuable for cell biological, biochemical and whole genome approaches in which large numbers of homogeneous cells are required. An efficient genetic method to derive Drosophila cell lines using expression of an oncogenic form of Ras (Ras(V12 has been developed. Mutations in tumor suppressors, which are known to cause cell hyperproliferation in vivo, could provide another method for generating Drosophila cell lines. Here we screened Drosophila tumor suppressor mutations to test if they promoted cell proliferation in vitro. We generated primary cultures and determined when patches of proliferating cells first emerged. These cells emerged on average at 37 days in wild-type cultures. Using this assay we found that a Pten mutation had a strong effect. Patches of proliferating cells appeared on average at 11 days and the cultures became confluent in about 3 weeks, which is similar to the timeframe for cultures expressing Ras(V12. Three Pten mutant cell lines were generated and these have now been cultured for between 250 and 630 cell doublings suggesting the life of the mutant cells is likely to be indefinite. We conclude that the use of Pten mutants is a powerful means to derive new Drosophila cell lines.

  7. Pancreas-specific Pten deficiency causes partial resistance to diabetes and elevated hepatic AKT signaling

    Institute of Scientific and Technical Information of China (English)

    Zan Tong; Yan Fan; Weiqi Zhang; Jun Xu; Jing Cheng; Mingxiao Ding; Hongkui Deng

    2009-01-01

    PTEN, a negative regulator of the phosphatidylinositol-3-kinase/AKT pathway, is an important modulator of insu-lin signaling. To determine the metabolic function of pancreatic Pten, we generated pancreas-specific Pten knockout (PPKO) mice. PPKO mice had enlarged pancreas and elevated proliferation of acinar cells. They also exhibited hy-poglycemia, hypoinsulinemia, and altered amino metabolism. Notably, PPKO mice showed delayed onset of strepto-zotocin (STZ)-induced diabetes and sex-biased resistance to high-fat-diet (HFD)-induced diabetes. To investigate the mechanism for the resistance to HFD-induced hyperglycemia in PPKO mice, we evaluated AKT phosphorylation in major insulin-responsive tissues: the liver, muscle, and fat. We found that Pten loss in the pancreas causes the eleva-tion of AKT signaling in the liver. The phosphorylation of AKT and its downstream substrate GSK3β was increased in the liver of PPKO mice, while PTEN level was decreased without detectable excision of Pten allele in the liver of PPKO mice. Proteomics analysis revealed dramatically decreased level of 78-kDa glucose-regulated protein (GRP78) in the liver of PPKO mice, which may also contribute to the lower blood glucose level of PPKO mice fed with HFD. Together, our findings reveal a novel response in the liver to pancreatic defect in metabolic regulation, adding a new dimension to understanding diabetes resistance.

  8. Relationsip between PTEN and VEGF Expression and Clinicopathological Characteristics in HCC

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To investigate the expressions and significance of the tumor suppressor gene phosphatase and tensin homlog deleted on chromosome ten protein (PTEN) and vascular endothelial growth factor (VEGF) in hepatocellular carcinoma (HCC), and to analyze the relationship between their expressions and the tumor's invasion and their pericarcinomatous tissues, the correlation of their expressions with the tumor's clinicopathological characteristics and invasion potential were studied. Our study showed that the expression level of PTEN in HCC was remarkably lower than that in pericarcinomatous liver tissues, while the expressions of both VEGF and MVD were higher than that in pericarcinomatous liver tissues. Correlation analysis revealed that the expression of PTEN was negatively related to the progression of the pathological differentiation and invasion of tumor, whereas the expressions of VEGF and MVD were positively related. Moreover, there was a negative relationship between the expression of PTEN and the expressions of VEGF and MVD, and a positive one between VEGF and MVD. The expressions of PTEN and VEGF may reveal the degree of differentiation and the invasive potential of HCC tissues. The mechanism by which the lack of PTEN expression probably induces abnormal hyperexpression of VEGF may play an important role in the invasion and metastasis of HCC.

  9. Exogenous PTEN Gene Induces Apoptosis in Breast Carcinoma Cell Line MDA468

    Institute of Scientific and Technical Information of China (English)

    CHEN Qingyong; WANG Chunyou; JIANG Chunfang; CHEN Daoda

    2007-01-01

    The effects and mechanisms of exogenous phosphatase and tensin homolog deleted from chromosome ten (PTEN) gene on phosphatase activity-dependent apoptosis of breast cancer cell line MDA468 were investigated. PTEN gene packaged with lipofectin was transferred into breast cancer cell line MDA468 and parental MDA468 cells served as controls. RT-PCR and Western blot were done to detect the expression of target genes. The expression of phosphospecific protein kinase B (PKB/Akt) and focal adhesion kinase (FAK) protein stimulated by epidermal growth factor (EGF) was also detected. Apoptosis was determined by flow cytometry with a double-staining method using FITC-conjugated annexin V and PI. MDA468 cells transfected with PTEN gene could express PTEN mRNA and protein. PTEN decreased the phosphorylation level of AKT protein and down-regulated FAK protein expression in MDA468 stimulated by EGF. The apoptosis rate was 21.68%. PTEN induced breast cancer apoptosis phosphatase activity-dependently. The mechanism is possibly relatedwith phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB)/AKT signaling pathway. Those results may provide new clues on the gene therapy in breast cancer.

  10. Myeloid PTEN deficiency protects livers from ischemia reperfusion injury by facilitating M2 macrophage differentiation.

    Science.gov (United States)

    Yue, Shi; Rao, Jianhua; Zhu, Jianjun; Busuttil, Ronald W; Kupiec-Weglinski, Jerzy W; Lu, Ling; Wang, Xuehao; Zhai, Yuan

    2014-06-01

    Although the role of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in regulating cell proliferation is well established, its function in immune responses remains to be fully appreciated. In the current study, we analyzed myeloid-specific PTEN function in regulating tissue inflammatory immune response in a murine liver partial warm ischemia model. Myeloid-specific PTEN knockout (KO) resulted in liver protection from ischemia reperfusion injury (IRI) by deviating the local innate immune response against ischemia reperfusion toward the regulatory type: expression of proinflammatory genes was selectively decreased and anti-inflammatory IL-10 was simultaneously increased in ischemia reperfusion livers of PTEN KO mice compared with those of wild-type (WT) mice. PI3K inhibitor and IL-10-neutralizing Abs, but not exogenous LPS, recreated liver IRI in these KO mice. At the cellular level, Kupffer cells and peritoneal macrophages isolated from KO mice expressed higher levels of M2 markers and produced lower TNF-α and higher IL-10 in response to TLR ligands than did their WT counterparts. They had enhanced Stat3- and Stat6-signaling pathway activation, but diminished Stat1-signaling pathway activation, in response to TLR4 stimulation. Inactivation of Kupffer cells by gadolinium chloride enhanced proinflammatory immune activation and increased IRI in livers of myeloid PTEN KO mice. Thus, myeloid PTEN deficiency protects livers from IRI by facilitating M2 macrophage differentiation.

  11. PTEN mutation analysis in two genetic subtypes of high-grade oligodendroglial tumors. PTEN is only occasionally mutated in one of the two genetic subtypes.

    Science.gov (United States)

    Jeuken, J W; Nelen, M R; Vermeer, H; van Staveren, W C; Kremer, H; van Overbeeke, J J; Boerman, R H

    2000-05-01

    We recently identified two genetic subtypes of high-grade oligodendroglial tumors (HG-OT): 1p-/19q- HG-OT are characterized by a loss of chromosome 1p32-36 (del(1)(p32-p36) and/or a del(19)(q13. 3); whereas +7/-10 HG-OT harbor a gain of chromosome 7 (+7) and/or a -10 without a loss of 1p32-36 and 19q13.3. Because a -10 and a +7 are most frequently detected in glioblastomas (GBM), the genotype of +7/-10 HG-OT suggests that these tumors are GBM with a prominent oligodendroglial phenotype rather than anaplastic oligodendrogliomas. PTEN is a tumor suppressor gene, located at 10q23.3, which is involved in tumor progression of GBM and other neoplasms. In this study, we screened for PTEN mutations in six low-grade oligodendroglial tumors (LG-OT), five 1p-/19q- HG-OT, seven +7/-10 HG-OT, and nine xenografted GBM. PTEN mutations were detected in none of the LG-OT and 1p-/19q- HG-OT, once in +7/-10 HG-OT, and frequently in GBM. As one of the +7/-10 HG-OT harbored a PTEN mutation, this demonstrates that PTEN can be involved in the oncogenesis of this genetic subtype of HG-OT. The lower frequency of PTEN mutations in +7/-10 HG-OT compared to GBM suggests that these tumors are of a distinct tumor type rather than GBM. Published by Elsevier Science Inc.

  12. Biological and genetic properties of the p53 null preneoplastic mammary epithelium

    Science.gov (United States)

    Medina, Daniel; Kittrell, Frances S.; Shepard, Anne; Stephens, L. Clifton; Jiang, Cheng; Lu, Junxuan; Allred, D. Craig; McCarthy, Maureen; Ullrich, Robert L.

    2002-01-01

    The absence of the tumor suppressor gene p53 confers an increased tumorigenic risk for mammary epithelial cells. In this report, we describe the biological and genetic properties of the p53 null preneoplastic mouse mammary epithelium in a p53 wild-type environment. Mammary epithelium from p53 null mice was transplanted serially into the cleared mammary fat pads of p53 wild-type BALB/c female to develop stable outgrowth lines. The outgrowth lines were transplanted for 10 generations. The outgrowths were ductal in morphology and progressed through ductal hyperplasia and ductal carcinoma in situ before invasive cancer. The preneoplastic outgrowth lines were immortal and exhibited activated telomerase activity. They are estrogen and progesterone receptor-positive, and aneuploid, and had various levels of tumorigenic potential. The biological and genetic properties of these lines are distinct from those found in most hyperplastic alveolar outgrowth lines, the form of mammary preneoplasia occurring in most traditional models of murine mammary tumorigenesis. These results indicate that the preneoplastic cell populations found in this genetically engineered model are similar in biological properties to a subset of precurser lesions found in human breast cancer and provide a unique model to identify secondary events critical for tumorigenicity and invasiveness.

  13. Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

    Directory of Open Access Journals (Sweden)

    Mayara C. Rosolem

    2015-11-01

    Full Text Available ABSTRACT: Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group, in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment.

  14. Cellular quiescence in mammary stem cells and breast tumor stem cells: got testable hypotheses?

    Science.gov (United States)

    Harmes, David C; DiRenzo, James

    2009-03-01

    Cellular quiescence is a state of reversible cell cycle arrest and has more recently been shown to be a blockade to differentiation and to correlate with resistance to cancer chemotherapeutics and other xenobiotics; features that are common to adult stem cells and possibly tumor stem cells. The biphasic kinetics of mammary regeneration, coupled to its cyclic endocrine control suggest that mammary stem cells most likely divide during a narrow window of the regenerative cycle and return to a state of quiescence. This would enable them to retain their proliferative capacity, resist differentiation signals and preserve their prolonged life span. There is accumulating evidence that mammary stem cells and other adult stem cells utilize quiescence for this purpose, however the degree to which tumor stem cells do so is largely unknown. The retained proliferative capacity of mammary stem cells likely enables them to accumulate and harbor mutations that lead to breast cancer initiation. However it is currently unclear if these causative lesions lead to defective or deranged quiescence in mammary stem cells. Evidence of such effects could potentially lead to the development of diagnostic systems that monitor mammary stem cell quiescence or activation. Such systems may be useful for the evaluation of patients who are at significant risk of breast cancer. Additionally quiescence has been postulated to contribute to therapeutic resistance and tumor recurrence. This review aims to evaluate what is known about the mechanisms governing cellular quiescence and the role of tumor stem cell quiescence in breast cancer recurrence.

  15. /sup 20/neon ion- and x-ray-induced mammary carcinogenesis in female rats

    Energy Technology Data Exchange (ETDEWEB)

    Shellabarger, C.J.; Baum, J.W.; Holtzman, S.; Stone, J.P.

    1983-01-01

    One of the proposed uses of heavy ion irradiation is to image lesions of the human female breast. The rat model system was chosen to assess the carcinogenic potential of heavy ion irradiation in the belief that data obtained from rat studies would have a qualitatively predictive value for the human female. Accordingly, female rats were exposed to /sup 20/Ne ions at the BEVALAC and studied for the development of mammary neoplasia for 312 +- 2 days at Brookhaven along with rats exposed concurrently to x-irradiation or to no irradiation. As the dose of either type of radiation was increased the percent of rats with mammary adenocarcinomas, and the percent of rats with mammary fibroadenomas, tended to increase. At a prevalence of 20%, the RBE for /sup 20/Neon ions for mammary adenocarcinomas was estimated to be larger than 5 and for mammary fibroadenomas the RBE was estimated to be less than 2. No conclusion was reached concerning whether or not the RBE might vary with dose. We suggest that /sup 20/Ne ions do have a carcinogenic potential for rat mammary tissue and that this carcinogenic potential is likely to be greater than for x-irradiation. (DT)

  16. Quantification of mammary organoid toxicant response and mammary tissue motility using OCT fluctuation spectroscopy (Conference Presentation)

    Science.gov (United States)

    Yu, Xiao; Blackmon, Richard L.; Carabas-Hernendez, Patricia; Fuller, Ashley; Troester, Melissa A.; Oldenburg, Amy L.

    2016-03-01

    Mammary epithelial cell (MEC) organoids in 3D culture recapitulate features of breast ducts in vivo. OCT has the ability to monitor the evolution of MEC organoids non-invasively and longitudinally. The anti-cancer drug Doxorubicin (Dox) is able to inhibit proliferation of cancer cells and has been widely used for chemotherapy of breast cancers; while environmental toxins implicated in breast cancer such as estrogen regulates mammary tumor growth and stimulates the proliferation and metastatic potential of breast cancers. Here we propose a quantitative method for measuring motility of breast cells in 3D cultures based upon OCT speckle fluctuation spectroscopy. The metrics of the inverse power-law exponent (α) and fractional modulation amplitude (M) were extracted from speckle fluctuation spectra. These were used to quantify the responses of MEC organoids to Dox, and estrogen. We investigated MEC organoids comprised of two different MEC lines: MCF10DCIS.com exposed to Dox, and MCF7 exposed to estrogen. We found an increase (pbreast cancer development and assessing anti-cancer drugs.

  17. Int-6, a highly conserved, widely expressed gene, is mutated by mouse mammary tumor virus in mammary preneoplasia.

    OpenAIRE

    Marchetti, A.; Buttitta, F.; Miyazaki, S; Gallahan, D; Smith, G H; Callahan, R

    1995-01-01

    With a unique mouse mammary tumor model system in which mouse mammary tumor virus (MMTV) insertional mutations can be detected during progression from preneoplasia to frank malignancy, including metastasis, we have discovered a new common integration site (designated Int-6) for MMTV in mouse mammary tumors. MMTV was integrated into Int-6 in a mammary hyperplastic outgrowth line, its tumors and metastases, and two independent mammary tumors arising in unrelated mice. The Int-6 gene is ubiquito...

  18. The transcription factor ATF3 acts as an oncogene in mouse mammary tumorigenesis

    Directory of Open Access Journals (Sweden)

    Thames Howard D

    2008-09-01

    Full Text Available Abstract Background Overexpression of the bZip transcription factor, ATF3, in basal epithelial cells of transgenic mice under the control of the bovine cytokeratin-5 (CK5 promoter has previously been shown to induce epidermal hyperplasia, hair follicle anomalies and neoplastic lesions of the oral mucosa including squamous cell carcinomas. CK5 is known to be expressed in myoepithelial cells of the mammary gland, suggesting the possibility that transgenic BK5.ATF3 mice may exhibit mammary gland phenotypes. Methods Mammary glands from nulliparous mice in our BK5.ATF3 colony, both non-transgenic and transgenic, were examined for anomalies by histopathology and immunohistochemistry. Nulliparous and biparous female mice were observed for possible mammary tumor development, and suspicious masses were analyzed by histopathology and immunohistochemistry. Human breast tumor samples, as well as normal breast tissue, were similarly analyzed for ATF3 expression. Results Transgenic BK5.ATF3 mice expressed nuclear ATF3 in the basal layer of the mammary ductal epithelium, and often developed squamous metaplastic lesions in one or more mammary glands by 25 weeks of age. No progression to malignancy was seen in nulliparous BK5.ATF3 or non-transgenic mice held for 16 months. However, biparous BK5.ATF3 mice developed mammary carcinomas with squamous metaplasia between 6 months and one year of age, reaching an incidence of 67%. Cytokeratin expression in the tumors was profoundly disturbed, including expression of CK5 and CK8 (characteristic of basal and luminal cells, respectively throughout the epithelial component of the tumors, CK6 (potentially a stem cell marker, CK10 (a marker of interfollicular epidermal differentiation, and mIRSa2 and mIRSa3.1 (markers of the inner root sheath of hair follicles. Immunohistochemical studies indicated that a subset of human breast tumors exhibit high levels of nuclear ATF3 expression. Conclusion Overexpression of ATF3 in CK5

  19. Adenoma of anogenital mammary-like glands.

    Science.gov (United States)

    Ahmed, Sartaj; Campbell, Ross M; Li, Jin Hong; Wang, Li Juan; Robinson-Bostom, Leslie

    2007-11-01

    Adenomas in the anogenital region are uncommon. There has been debate about the origin, including ectopic breast tissue, cutaneous apocrine gland, and most recently anogenital mammary-like gland. An anogenital mass in a 36-year-old woman was excised, and histopathologic examination and immunostaining were performed. Microscopic tissue sections showed a morphologic pattern similar to that of a mammary fibroadenoma, and immunostaining demonstrated the presence of estrogen receptors and progesterone receptors. The possibility of adenomas of anogenital mammary-like glands should be considered when evaluating patients with a mass in this area with confirmation by tissue biopsy or aspiration cytology.

  20. Long-term consequences of conditional genetic deletion of PTEN in the sensorimotor cortex of neonatal mice.

    Science.gov (United States)

    Gutilla, Erin A; Buyukozturk, Melda M; Steward, Oswald

    2016-05-01

    Targeted deletion of the phosphatase and tensin homolog on chromosome ten (PTEN) gene in the sensorimotor cortex of neonatal mice enables robust regeneration of corticospinal tract (CST) axons following spinal cord injury as adults. Here, we assess the consequences of long-term conditional genetic PTEN deletion on cortical structure and neuronal morphology and screen for neuropathology. Mice with a LoxP-flanked exon 5 of the PTEN gene (PTENf/f mice) received AAV-Cre injections into the sensorimotor cortex at postnatal day 1 (P1) and were allowed to survive for up to 18months. As adults, mice were assessed for exploratory activity (open field), and motor coordination using the Rotarod®. Some mice received injections of Fluorogold into the spinal cord to retrogradely label the cells of origin of the CST. Brains were prepared for neurohistology and immunostained for PTEN and phospho-S6, which is a downstream marker of mammalian target of rapamycin (mTOR) activation. Immunostaining revealed a focal area of PTEN deletion affecting neurons in all cortical layers, although in some cases PTEN expression was maintained in many small-medium sized neurons in layers III-IV. Neurons lacking PTEN were robustly stained for pS6. Cortical thickness was significantly increased and cortical lamination was disrupted in the area of PTEN deletion. PTEN-negative layer V neurons that give rise to the CST, identified by retrograde labeling, were larger than neurons with maintained PTEN expression, and the relative area occupied by neuropil vs. cell bodies was increased. There was no evidence of tumor formation or other neuropathology. Mice with PTEN deletion exhibited open field activity comparable to controls and there was a trend for impaired Rotarod performance (not statistically significant). Our findings indicate that early postnatal genetic deletion of PTEN that is sufficient to enable axon regeneration by adult neurons causes neuronal hypertrophy but no other detectable

  1. EFFECTS OF MUTATION AND EXPRESSION OF PTEN GENE mRNA ON TUMORIGENESIS AND PROGRESSION OF EPITHELIAL OVARIAN CANCER

    Institute of Scientific and Technical Information of China (English)

    陈颖; 郑华川; 杨雪飞; 孙丽梅; 辛彦

    2004-01-01

    Objective To investigate the mutation and expression of tumor suppressor gene-PTEN mRNA and explore their roles in tumorigenesis and progression of ovarian cancer. Methods Mutated exon 5 of PTEN gene was examined in normal ovary (n = 5), ovarian cyst (n =5), ovarian borderline tumor (n=9), epithelial ovarian cancer (n=60), and ovarian cancer cell line (n= 1)by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). mRNA expression of PTEN gene was evaluated in corresponding tissues and cell line by reverse transcription polymerase chain reaction(RT-PCR). The mutation and mRNA expression of PTEN gene were compared with clinicopathological features of ovarian cancer. Results Mutated exon 5 of PTEN gene was detected only in 5 (7.1%) cases of epithelial ovarian cancer. mRNA expression level of PTEN gene in ovarian borderline tumor or ovarian cancer was lower than that in normal ovary or ovarian cyst (P < 0.05). The level of PTEN gene mRNA expression was negatively correlated with clinicopathological staging of ovarian cancer, whereas positively correlated with histological differentiation (P < 0.05). mRNA expression level of PTEN gene in ovarian endometrioid cancer was significantly lower than that in ovarian serous or mucinous cancer (P < 0.05). Conclusions Mutation of PTEN gene occurs in ovarian cancer. Down-regulated expression of PTEN is probably an important molecular event in tumorigenesis of ovarian cancer. Abnormal expression of PTEN gene is involved in progression of ovarian cancer. Reduced expression of PTEN gene is closely associated with tumorigenesis and pathobiological behaviors of ovarian endometrioid cancer.

  2. Developmental signaling pathways regulating mammary stem cells and contributing to the etiology of triple-negative breast cancer.

    Science.gov (United States)

    Rangel, Maria Cristina; Bertolette, Daniel; Castro, Nadia P; Klauzinska, Malgorzata; Cuttitta, Frank; Salomon, David S

    2016-04-01

    Cancer has been considered as temporal and spatial aberrations of normal development in tissues. Similarities between mammary embryonic development and cell transformation suggest that the underlying processes required for mammary gland development are also those perturbed during various stages of mammary tumorigenesis and breast cancer (BC) development. The master regulators of embryonic development Cripto-1, Notch/CSL, and Wnt/β-catenin play key roles in modulating mammary gland morphogenesis and cell fate specification in the embryo through fetal mammary stem cells (fMaSC) and in the adult organism particularly within the adult mammary stem cells (aMaSC), which determine mammary progenitor cell lineages that generate the basal/myoepithelial and luminal compartments of the adult mammary gland. Together with recognized transcription factors and embryonic stem cell markers, these embryonic regulatory molecules can be inappropriately augmented during tumorigenesis to support the tumor-initiating cell (TIC)/cancer stem cell (CSC) compartment, and the effects of their deregulation may contribute for the etiology of BC, in particular the most aggressive subtype of BC, triple-negative breast cancer (