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Montes-de-Oca-Fuentes EV, Jácome-López K, Zarco-Mendoza A, Guerrero G, Ventura-Gallegos JL, Juárez-Méndez S, Cabrera-Quintero AJ, Recillas-Targa F, Zentella-Dehesa A. Differential DNA methylation and CTCF binding between the ESR1 promoter a of MCF-7 and MDA-MB-231 breast cancer cells. Mol Biol Rep 2024; 51:148. [PMID: 38236307 PMCID: PMC10796618 DOI: 10.1007/s11033-023-09171-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 12/15/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND ESR1 is expressed by 60-70% of breast tumours. it's a good prognosis factor and the target of hormone therapy. Optimization of ESR1 reactivation therapy is currently ongoing. Here we probe if the transcription factor CTCF plays a role in the differential expression of ESR1 in the breast cancer cell lines MCF-7 (ESR1+) and MDA-MB-231 (ESR1-). METHODS AND RESULTS Knockdown of CTCF in MCF-7 resulted in decreased ESR1 gene expression. CTCF binds to the promoter of ESR1 in MCF-7 but not in MDA-MB-231 cells. CTCF ESR1 binding sites are unmethylated in MCF7 but methylated in MDA-MB-231 cells. CONCLUSION ESR1 expression in MCF7 cells is dependent on CTCF expression. CTCF can bind to specific regions of the promotor of ESR1 gene in MCF-7 cells but not in MDA-MB-231 cells, this correlates with the methylation status of these regions and could be involved in the transcriptional regulation of ESR1.
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Affiliation(s)
- Edén Víctor Montes-de-Oca-Fuentes
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
- Programa de Investigación en Cáncer de Mama, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
- Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México
| | - Karina Jácome-López
- Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México
| | - Anaís Zarco-Mendoza
- División de Investigación Básica, Laboratorio de Virus y Cancer, Secretaría de Salud, Instituto Nacional de Cancerología, Ciudad de México, 14080, México
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Georgina Guerrero
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - José Luis Ventura-Gallegos
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
- Programa de Investigación en Cáncer de Mama, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
- Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México
| | - Sergio Juárez-Méndez
- Laboratorio de Oncología Experimental, Secretaría de Salud, Instituto Nacional de Pediatría, Ciudad de México, 04530, México
| | - Alberto Jose Cabrera-Quintero
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
- Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México
| | - Félix Recillas-Targa
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Alejandro Zentella-Dehesa
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México.
- Programa de Investigación en Cáncer de Mama, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico.
- Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México.
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México‑Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México, 14080, México.
- Cancer Center, American British Cowdray Medical Center, Ciudad de México, 01120, Mexico.
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Intabli H, Gee JM, Oesterreich S, Yeoman MS, Allen MC, Qattan A, Flint MS. Glucocorticoid induced loss of oestrogen receptor alpha gene methylation and restoration of sensitivity to fulvestrant in triple negative breast cancer. Gene 2023; 851:147022. [PMID: 36347335 PMCID: PMC11188041 DOI: 10.1016/j.gene.2022.147022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 10/25/2022] [Indexed: 11/08/2022]
Abstract
The response to psychological stress can differ depending on the type and duration of the stressor. Acute stress can facilitate a "fight or flight response" and aid survival, whereas chronic long-term stress with the persistent release of stress hormones such as cortisol has been shown to be detrimental to health. We are now beginning to understand how this stress hormone response impacts important processes such as DNA repair and cell proliferation processes in breast cancer. However, it is not known what epigenetic changes stress hormones induce in breast cancer. Epigenetic mechanisms include modification of DNA and histones within chromatin that may be involved in governing the transcriptional processes in cancer cells in response to changes by endogenous stress hormones. The contribution of endogenous acute or long-term exposure of glucocorticoid stress hormones, and exogenous glucocorticoids to methylation patterns in breast cancer tissues with different aetiologies remains to be evaluated. In vitro and in vivo models were developed to investigate the epigenetic modifications and their contribution to breast cancer progression and aetiology. A panel of triple negative breast cancer cell lines were treated with the glucocorticoid, cortisol which resulted in epigenetic alteration characterised by loss of methylation on promoter regions of tumour suppressor genes including ESR1, and loss of methylation on LINE-1 repetitive element used as a surrogate marker for global methylation. This was verified in vivo in MDA-MB-231 xenografts; the model verified the loss of methylation on ESR1 promoter, and subsequent increase in ESR1 expression in primary tumours in mice subjected to restraint stress. Our study highlights that DNA methylation landscape in breast cancer can be altered in response to stress and glucocorticoid treatment.
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Affiliation(s)
- Haya Intabli
- Centre for Stress and Age-Related Disease, School of Pharmacy and Biomolecular Science, University of Brighton, Brighton BN2 4GJ, UK
| | - Julia M Gee
- Breast Cancer Molecular Pharmacology Group, School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Wales CF10 3NB, UK
| | - Steffi Oesterreich
- Department of Pharmacology and Chemical Biology, Women's Cancer Research Center, UPMC Hillman Cancer Center and Magee Womens Research Institute, Pittsburgh, PA 15232, USA; UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Magee-Women's Research Institute and Women's Cancer Research Center, Pittsburgh, PA, USA
| | - Mark S Yeoman
- Centre for Stress and Age-Related Disease, School of Pharmacy and Biomolecular Science, University of Brighton, Brighton BN2 4GJ, UK
| | - Marcus C Allen
- Centre for Stress and Age-Related Disease, School of Pharmacy and Biomolecular Science, University of Brighton, Brighton BN2 4GJ, UK
| | - Amal Qattan
- Translational Cancer Research Section, Department of Molecular Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Melanie S Flint
- Centre for Stress and Age-Related Disease, School of Pharmacy and Biomolecular Science, University of Brighton, Brighton BN2 4GJ, UK.
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Cao Y, Chen Z, Zhang M, Shi L, Qin S, Lv D, Li D, Ma L, Zhang Y. Maternal exposure to bisphenol A induces fetal growth restriction via upregulating the expression of estrogen receptors. CHEMOSPHERE 2022; 287:132244. [PMID: 34537452 DOI: 10.1016/j.chemosphere.2021.132244] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/23/2021] [Accepted: 09/11/2021] [Indexed: 06/13/2023]
Abstract
Bisphenol A (BPA) accumulation in the placenta leads to fetal growth restriction (FGR). Here we aimed to explore the effect and the underlying mechanism of BPA exposure on fetal development. ELISA was performed to measure estrogen levels in human placenta and BeWo cells. qRT-PCR and Western blotting were conducted to determine the expression of estrogen receptors (ERs), breast cancer resistance protein (BCRP), the key enzymes for ER synthesis, and DNA methyltransferases (DNMTs). Bisulfite-sequencing PCR analysis was performed to measure CpG methylation in ER genes. Flow cytometry was used to examine cell apoptosis. We found that human FGR placentae had significantly increased BPA and estrogen levels and decreased BCRP levels compared with healthy placentae. BPA downregulated BCRP expression via ERs, and BCRP silencing promoted ER expression in BeWo cells. Compared with vehicle treatment, BPA treatment significantly enhanced the expression of key enzymes for estrogen synthesis and ERs in BeWo cells. BPA treatment inhibited CpG methylation in ER genes, along with downregulated DNMT1 expression and upregulated DNMT3a and DNMT3b expression. BPA treatment significantly promoted BeWo cell apoptosis compared with vehicle treatment. Importantly, ER inhibitor ICI-182780 significantly reversed all the BPA-induced effects on BeWo cells. In conclusion, BPA promotes estrogen production and cell apoptosis in BeWo cells via upregulating ER expression, leading to FGR.
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Affiliation(s)
- Yuming Cao
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Clinical Medicine Research Center for Prenatal Diagnosis and Birth Health, Wuhan, Hubei, 430071, China
| | - Zhenlie Chen
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Clinical Medicine Research Center for Prenatal Diagnosis and Birth Health, Wuhan, Hubei, 430071, China
| | - Ming Zhang
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Clinical Medicine Research Center for Prenatal Diagnosis and Birth Health, Wuhan, Hubei, 430071, China
| | - Lei Shi
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China
| | - Songling Qin
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China
| | - Dan Lv
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China
| | - Danyang Li
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China
| | - Ling Ma
- Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Clinical Medicine Research Center for Prenatal Diagnosis and Birth Health, Wuhan, Hubei, 430071, China.
| | - Yuanzhen Zhang
- Department of Gynaecology and Obstetrics, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Reproductive Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, China; Clinical Medicine Research Center for Prenatal Diagnosis and Birth Health, Wuhan, Hubei, 430071, China.
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Methylation of Estrogen Receptor 1 Gene in the Paraspinal Muscles of Girls with Idiopathic Scoliosis and Its Association with Disease Severity. Genes (Basel) 2021; 12:genes12060790. [PMID: 34064195 PMCID: PMC8224318 DOI: 10.3390/genes12060790] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/11/2021] [Accepted: 05/20/2021] [Indexed: 12/13/2022] Open
Abstract
Idiopathic scoliosis (IS) is a multifactorial disease with epigenetic modifications. Tissue dependent and differentially methylated regions (T-DMRs) may regulate tissue-specific expression of the estrogen receptor 1 gene (ESR1). This study aimed to analyze methylation levels within T-DMR1 and T-DMR2 and its concatenation with ESR1 expression of IS patients. The study involved 87 tissue samples (deep paravertebral muscles, both on the convex and the concave side of the curve, and from back superficial muscles) from 29 girls who underwent an operation due to IS. Patient subgroups were analyzed according to Cobb angle ≤70° vs. >70°. Methylation was significantly higher in the superficial muscles than in deep paravertebral muscles in half of the T-DMR1 CpGs and all T-DMR2 CpGs. The methylation level correlated with ESR1 expression level on the concave, but not convex, side of the curvature in a majority of the T-DMR2 CpGs. The T-DMR2 methylation level in the deep paravertebral muscles on the curvature's concave side was significantly lower in patients with a Cobb angle ≤70° in four CpGs. DNA methylation of the T-DMRs is specific to muscle tissue location and may be related to ESR1 expression regulation. Additionally, the difference in T-DMR2 methylation may be associated with IS severity.
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Hua H, Zhang H, Kong Q, Jiang Y. Mechanisms for estrogen receptor expression in human cancer. Exp Hematol Oncol 2018; 7:24. [PMID: 30250760 PMCID: PMC6148803 DOI: 10.1186/s40164-018-0116-7] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/12/2018] [Indexed: 02/06/2023] Open
Abstract
Estrogen is a steroid hormone that has critical roles in reproductive development, bone homeostasis, cardiovascular remodeling and brain functions. However, estrogen also promotes mammary, ovarian and endometrial tumorigenesis. Estrogen antagonists and drugs that reduce estrogen biosynthesis have become highly successful therapeutic agents for breast cancer patients. The effects of estrogen are largely mediated by estrogen receptor (ER) α and ERβ, which are members of the nuclear receptor superfamily of transcription factors. The mechanisms underlying the aberrant expression of ER in breast cancer and other types of human tumors are complex, involving considerable alternative splicing of ERα and ERβ, transcription factors, epigenetic and post-transcriptional regulation of ER expression. Elucidation of mechanisms for ER expression may not only help understand cancer progression and evolution, but also shed light on overcoming endocrine therapy resistance. Herein, we review the complex mechanisms for regulating ER expression in human cancer.
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Affiliation(s)
- Hui Hua
- 1Laboratory of Stem Cell Biology, West China Hospital, Sichuan University, Chengdu, China
| | - Hongying Zhang
- 2Laboratory of Oncogene, West China Hospital, Sichuan University, Chengdu, China
| | - Qingbin Kong
- 2Laboratory of Oncogene, West China Hospital, Sichuan University, Chengdu, China
| | - Yangfu Jiang
- 2Laboratory of Oncogene, West China Hospital, Sichuan University, Chengdu, China
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6
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Reichenstein M, Rauner G, Kfir S, Kisliouk T, Barash I. Luminal STAT5 mediates H2AX promoter activity in distinct population of basal mammary epithelial cells. Oncotarget 2018; 7:41781-41797. [PMID: 27260000 PMCID: PMC5173096 DOI: 10.18632/oncotarget.9718] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 05/20/2016] [Indexed: 01/08/2023] Open
Abstract
Deregulated STAT5 activity in the mammary gland causes parity-dependent tumorigenesis. Epithelial cell cultures transfected with constitutively active STAT5 express higher levels of the histone H2AX than their non-transfected counterparts. Higher H2AX expression may be involved in tumorigenesis. Here, we aimed to link high STAT5 activity to H2AX–GFP expression by looking for distinct types of mammary cells that express these proteins. In vitro and in transgenic mice, only 0.2 and 0.02%, respectively, of the cells expressed the H2AX–GFP hybrid gene. Its expression correlated with that of the endogenous H2AX gene, suggesting that detectable H2AX–GFP expression marks high levels of H2AX transcript. Methylation of the H2AX promoter characterized non-GFP-expressing H2AX–GFP cells and was inversely correlated with promoter activity. Administration of 5-azacytidine increased H2AX promoter activity in an activated STAT5-dependent manner. In transgenic mice, H2AX–GFP expression peaked at pregnancy. The number of H2AX–GFP-expressing cells and GFP expression decreased in a Stat5a-null background and increased in mice expressing the hyperactivated STAT5. Importantly, H2AX–GFP activity was allocated to basal mammary cells lacking stem-cell properties, whereas STAT5 hyperactivity was detected in the adjacent luminal cells. Knockdown of RANKL by siRNA suggested its involvement in signaling between the two layers. These results suggest paracrine activation of H2AX via promoter demethylation in specific populations of basal mammary cells that is induced by a signal from neighboring luminal cells with hyper STAT5 activity. This pathway provides an alternative route for the luminally confined STAT5 to affect basal mammary cell activity.
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Affiliation(s)
| | - Gat Rauner
- Institute of Animal Science, ARO, The Volcani Center, Bet-Dagan, Israel.,The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Shenhav Kfir
- Institute of Animal Science, ARO, The Volcani Center, Bet-Dagan, Israel.,The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Tatiana Kisliouk
- Institute of Animal Science, ARO, The Volcani Center, Bet-Dagan, Israel
| | - Itamar Barash
- Institute of Animal Science, ARO, The Volcani Center, Bet-Dagan, Israel
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Parodi DA, Greenfield M, Evans C, Chichura A, Alpaugh A, Williams J, Cyrus KC, Martin MB. Alteration of Mammary Gland Development and Gene Expression by In Utero Exposure to Cadmium. Int J Mol Sci 2017; 18:E1939. [PMID: 28891935 PMCID: PMC5618588 DOI: 10.3390/ijms18091939] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/01/2017] [Accepted: 09/05/2017] [Indexed: 01/31/2023] Open
Abstract
Environmental exposure to estrogens and estrogen like contaminants during early development is thought to contribute to the risk of developing breast cancer primarily due to an early onset of puberty; however, exposure during key developing windows may also influence the risk of developing the disease. The goal of this study was to ask whether in utero exposure to the metalloestrogen cadmium alters mammary gland development due to acceleration of puberty onset or to an effect on early development of the mammary gland. The results show that, in addition to advancing the onset of puberty, in utero exposure to the metalloestrogen cadmium altered mammary gland development prior to its effect on puberty onset. In utero exposure resulted in an expansion of the number of mammosphere-forming cells in the neonatal mammary gland and an increase in branching, epithelial cells, and density in the prepubertal mammary gland. In the postpubertal mammary gland, there was a further expansion of the mammary stem/progenitor cell population and overexpression of estrogen receptor-alpha (ERα) that was due to the overexpression and altered regulation of the ERα transcripts derived from exons O and OT in response to estradiol. These results suggest that in utero exposure to cadmium increases stem/progenitor cells, cell density, and expression of estrogen receptor-alpha that may contribute to the risk of developing breast cancer.
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Affiliation(s)
- Daniela A Parodi
- Departments of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA.
| | - Morgan Greenfield
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
| | - Claire Evans
- Departments of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA.
| | - Anna Chichura
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
| | - Alexandra Alpaugh
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
| | - James Williams
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
| | - Kedra C Cyrus
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
| | - Mary Beth Martin
- Departments of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC 20007, USA.
- Department of Oncology, Georgetown University, Washington, DC 20007, USA.
- Lombardi Comprehensive Cancer Center, Research Building, 3970 Reservoir Road NW, Washington, DC 20007, USA.
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Chronic oxidative stress causes estrogen-independent aggressive phenotype, and epigenetic inactivation of estrogen receptor alpha in MCF-7 breast cancer cells. Breast Cancer Res Treat 2015. [DOI: 10.1007/s10549-015-3514-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Chen M, Xiao D, Hu XQ, Dasgupta C, Yang S, Zhang L. Hypoxia Represses ER-α Expression and Inhibits Estrogen-Induced Regulation of Ca2+-Activated K+ Channel Activity and Myogenic Tone in Ovine Uterine Arteries: Causal Role of DNA Methylation. Hypertension 2015; 66:44-51. [PMID: 25987666 DOI: 10.1161/hypertensionaha.115.05299] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 04/23/2015] [Indexed: 12/17/2022]
Abstract
Previous in vivo study demonstrated that chronic hypoxia during gestation was associated with estrogen receptor-α (ER-α) gene repression in ovine uterine arteries. Yet, it remains undetermined whether hypoxia had a direct effect and if DNA methylation played a causal role in hypoxia-mediated ER-α gene repression. Thus, this study tested the hypothesis that prolonged hypoxia has a direct effect and increases promoter methylation resulting in ER-α gene repression and inhibition of estrogen-mediated adaptation of uterine vascular tone. Uterine arteries isolated from nonpregnant and pregnant sheep were treated ex vivo with 21.0% O2 and 10.5% O2 for 48 hours. Hypoxia significantly increased ER-α promoter methylation at both specificity protein-1 and upstream stimulatory factor binding sites, decreased specificity protein-1 and upstream stimulatory factor binding to the promoter, and suppressed ER-α expression in uterine arteries of pregnant animals. Of importance, the effects of hypoxia were blocked by a methylation inhibitor 5-aza-2'-deoxycytidine. In addition, hypoxia abrogated steroid hormone-mediated increase in ER-α expression and inhibited the hormone-induced increase in large-conductance Ca(2+)-activated K(+) channel activity and decrease in myogenic tone in uterine arteries of nonpregnant animals, which were reversed by 5-aza-2'-deoxycytidine. The results provide novel evidence of a direct effect of hypoxia on heightened promoter methylation that plays a causal role in ER-α gene repression and ablation of steroid hormone-mediated adaptation of uterine arterial large conductance Ca(2+)-activated K(+) channel activity and myogenic tone in pregnancy.
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Affiliation(s)
- Man Chen
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.)
| | - Daliao Xiao
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.)
| | - Xiang-Qun Hu
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.)
| | - Chiranjib Dasgupta
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.)
| | - Shumei Yang
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.)
| | - Lubo Zhang
- From the Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, CA (M.C., D.X., X-.Q.H., C.D., L.Z.); and Department of Chemistry and Biochemistry, California State University, San Bernardino (S.Y.).
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10
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Demethylation within the proximal promoter region of human estrogen receptor alpha gene correlates with its enhanced expression: Implications for female bias in lupus. Mol Immunol 2014; 61:28-37. [DOI: 10.1016/j.molimm.2014.05.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 04/28/2014] [Accepted: 05/02/2014] [Indexed: 11/19/2022]
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Cotter KA, Yershov A, Novillo A, Callard GV. Multiple structurally distinct ERα mRNA variants in zebrafish are differentially expressed by tissue type, stage of development and estrogen exposure. Gen Comp Endocrinol 2013; 194:217-29. [PMID: 24090614 PMCID: PMC3862120 DOI: 10.1016/j.ygcen.2013.09.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 09/04/2013] [Accepted: 09/18/2013] [Indexed: 10/26/2022]
Abstract
It is well established that estrogen-like environmental chemicals interact with the ligand-binding site of estrogen receptors (ERs) to disrupt transcriptional control of estrogen responsive targets. Here we investigate the possibility that estrogens also impact splicing decisions on estrogen responsive genes, such as that encoding ERα itself. Targeted PCR cloning was applied to identify six ERα mRNA variants in zebrafish. Sequencing revealed alternate use of transcription and translation start sites, multiple exon deletions, intron retention and alternate polyadenylation. As determined by quantitative (q)PCR, N-terminal mRNA variants predicting long (ERαA(L)) and short (ERα(S)) isoforms were differentially expressed by tissue-type, sex, stage of development and estrogen exposure. Whereas ERα(L) mRNA was diffusely distributed in liver, brain, heart, eye, and gonads, ERα(S) mRNA was preferentially expressed in liver (female>male) and ovary. Neither ERα(L) nor ERα(S) transcripts varied significantly during development, but 17β-estradiol selectively increased accumulation of ERα(S) mRNA (∼170-fold by 120 hpf), an effect mimicked by bisphenol-A and diethylstilbestrol. Significantly, a C-truncated variant (ERα(S)-Cx) lacking most of the ligand binding and AF-2 domains was transcribed exclusively from the short isoform promoter and was similar to ERα(S) in its tissue-, stage- and estrogen inducible expression. These results support the idea that promoter choice and alternative splicing of the esr1 gene of zebrafish are part of the autoregulatory mechanism by which estrogen modulates subsequent ERα expression, and further suggest that environmental estrogens could exert some of their toxic effects by altering the relative abundance of structurally and functionally distinct ERα isoforms.
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Affiliation(s)
- Kellie A. Cotter
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Anya Yershov
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Apolonia Novillo
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Gloria V. Callard
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
- Corresponding author: (617-353-8980)
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Dasgupta C, Chen M, Zhang H, Yang S, Zhang L. Chronic hypoxia during gestation causes epigenetic repression of the estrogen receptor-α gene in ovine uterine arteries via heightened promoter methylation. Hypertension 2012; 60:697-704. [PMID: 22777938 DOI: 10.1161/hypertensionaha.112.198242] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Estrogen receptor-α (ERα) plays a key role in the adaptation of increased uterine blood flow in pregnancy. Chronic hypoxia is a common stress to maternal cardiovascular homeostasis and causes increased risk of preeclampsia. Studies in pregnant sheep demonstrated that hypoxia during gestation downregulated ERα gene expression in uterine arteries. The present study tested the hypothesis that hypoxia causes epigenetic repression of the ERα gene in uterine arteries via heightened promoter methylation. Ovine ERα promoter of 2035 bp spanning from -2000 to +35 of the transcription start site was cloned. No estrogen or hypoxia-inducible factor response elements were found at the promoter. Two transcription factor binding sites, USF(-15) and Sp1(-520), containing CpG dinucleotides were identified, which had significant effects on the promoter activity. The USF element binds transcription factors USF1 and USF2, and the Sp1 element binds Sp1, as well as ERα through Sp1. Deletion of the Sp1 site abrogated 17β-estradiol-induced increase in the promoter activity. In normoxic control sheep, CpG methylation at the Sp1 but not the USF site was significantly decreased in uterine arteries of pregnant as compared with nonpregnant animals. In pregnant sheep exposed to long-term high-altitude hypoxia, CpG methylation at both Sp1 and USF sites in uterine arteries was significantly increased. Methylation inhibited transcription factor binding and the promoter activity. The results provide evidence of hypoxia causing heightened promoter methylation and resultant ERα gene repression in uterine arteries and suggest new insights of molecular mechanisms linking gestational hypoxia to aberrant uteroplacental circulation and increased risk of preeclampsia.
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Affiliation(s)
- Chiranjib Dasgupta
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA
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Pathiraja TN, Stearns V, Oesterreich S. Epigenetic regulation in estrogen receptor positive breast cancer--role in treatment response. J Mammary Gland Biol Neoplasia 2010; 15:35-47. [PMID: 20101445 PMCID: PMC2874203 DOI: 10.1007/s10911-010-9166-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 01/07/2010] [Indexed: 02/07/2023] Open
Abstract
Recent advances in breast cancer treatment have allowed increasing numbers of patients with estrogen receptor (ER) positive (+) breast cancer to receive various forms of endocrine therapy. Unfortunately, de novo and acquired resistance to endocrine therapy remains a major challenge in the clinic. A number of possible mechanisms for drug resistance have been described, which include activation of growth factor receptor pathways, overexpression of ER coactivators, and metabolic resistance due to polymorphisms in metabolizing enzymes. While many of these changes are caused by genetic alterations, there is also increasing evidence to implicate epigenetic gene regulatory mechanisms in the development of endocrine resistance. Since epigenetic modifications are easier to reverse than genetic mutations, they are appealing therapeutic targets, and thus future improvements in medical care for breast cancer patients will depend upon a better understanding of the roles epigenetic modifications play in endocrine resistance. In this review we will focus on recent advances made in the understanding of epigenetic gene regulation in estrogen response and endocrine resistance in breast cancer. We will also summarize current clinical-translational advances in epigenetic therapy, and discuss potential future clinical use of epigenetic changes as therapeutic targets, especially with respect to endocrine treatment.
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Affiliation(s)
- Thushangi N. Pathiraja
- Translational Biology and Molecular Medicine Graduate Program, Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA
| | - Vered Stearns
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Steffi Oesterreich
- Lester and Sue Smith Breast Center, Department of Medicine, and Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA,
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Santen RJ, Brodie H, Simpson ER, Siiteri PK, Brodie A. History of aromatase: saga of an important biological mediator and therapeutic target. Endocr Rev 2009; 30:343-75. [PMID: 19389994 DOI: 10.1210/er.2008-0016] [Citation(s) in RCA: 284] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Aromatase is the enzyme that catalyzes the conversion of androgens to estrogens. Initial studies of its enzymatic activity and function took place in an environment focused on estrogen as a component of the birth control pill. At an early stage, investigators recognized that inhibition of this enzyme could have major practical applications for treatment of hormone-dependent breast cancer, alterations of ovarian and endometrial function, and treatment of benign disorders such as gynecomastia. Two general approaches ultimately led to the development of potent and selective aromatase inhibitors. One targeted the enzyme using analogs of natural steroidal substrates to work out the relationships between structure and function. The other approach initially sought to block adrenal function as a treatment for breast cancer but led to the serendipitous finding that a nonsteroidal P450 steroidogenesis inhibitor, aminoglutethimide, served as a potent but nonselective aromatase inhibitor. Proof of the therapeutic concept of aromatase inhibition involved a variety of studies with aminoglutethimide and the selective steroidal inhibitor, formestane. The requirement for even more potent and selective inhibitors led to intensive molecular studies to identify the structure of aromatase, to development of high-sensitivity estrogen assays, and to "mega" clinical trials of the third-generation aromatase inhibitors, letrozole, anastrozole, and exemestane, which are now in clinical use in breast cancer. During these studies, unexpected findings led investigators to appreciate the important role of estrogens in males as well as in females and in multiple organs, particularly the bone and brain. These studies identified the important regulatory properties of aromatase acting in an autocrine, paracrine, intracrine, neurocrine, and juxtacrine fashion and the organ-specific enhancers and promoters controlling its transcription. The saga of these studies of aromatase and the ultimate utilization of inhibitors as highly effective treatments of breast cancer and for use in reproductive disorders serves as the basis for this first Endocrine Reviews history manuscript.
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Affiliation(s)
- R J Santen
- University of Virginia Health System, Division of Endocrinology, P.O. Box 801416, Charlottesville, Virginia 22908, USA.
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Abstract
One of the most common cancers in women world wide, breast cancer is classically an endocrine-dependent cancer. It has been known for over a century that development, progression and metastasis of breast cancer are strongly influenced by hormonal factors. Indeed about two-thirds of breast cancers express the estrogen receptor α (ERα) protein, a key predictor of prognosis and response to endocrine therapy. These cancers are frequently amenable to therapies that target estrogen signaling pathways, including selective estrogen receptor modulators like tamoxifen, selective estrogen receptor downregulators like fulvestrant; and agents that reduce estrogen ligand like aromatase inhibitors and ovarian suppression through luteinizing hormone-releasing hormone (LHRH) agonists. It is likely that these approaches, especially adjuvant tamoxifen, have contributed to the reduction in breast cancer mortality that has been observed in recent years. However, data from clinical studies have suggested that only about 60% of ERα-positive breast cancers respond to hormonal therapy. Further, those tumors that lack expression of ERα and the estrogen-regulated progesterone receptor (PgR) are unresponsive to hormone therapy. Thus the problem of acquired or de novo endocrine resistance is a substantial one. Recent molecular and biological advances have contributed to our understanding about potential underlying mechanisms. Here we will focus especially on silencing the expression of ERα as one such endocrine-resistance mechanism and how it might be exploited clinically.
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Affiliation(s)
- Madhavi Billam
- The Sidney Kimmel Comprehensive Cancer Center; Johns Hopkins University; Baltimore, MD USA
| | - Abigail E. Witt
- The Sidney Kimmel Comprehensive Cancer Center; Johns Hopkins University; Baltimore, MD USA
| | - Nancy E. Davidson
- The Sidney Kimmel Comprehensive Cancer Center; Johns Hopkins University; Baltimore, MD USA
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Santen RJ, Song RX, Masamura S, Yue W, Fan P, Sogon T, Hayashi SI, Nakachi K, Eguchi H. Adaptation to Estradiol Deprivation Causes Up-Regulation of Growth Factor Pathways and Hypersensitivity to Estradiol in Breast Cancer Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 630:19-34. [DOI: 10.1007/978-0-387-78818-0_2] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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