Promoter Methylation Regulates Estrogen Receptor 2 in Human Endometrium and Endometriosis

Division of Reproductive Biology Research, Department of Obsterics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.
Biology of Reproduction (Impact Factor: 3.32). 11/2007; 77(4):681-7. DOI: 10.1095/biolreprod.107.061804
Source: PubMed


Steroid receptors in the stromal cells of endometrium and its disease counterpart tissue endometriosis play critical physiologic roles. We found that mRNA and protein levels of estrogen receptor 2 (ESR2) were strikingly higher, whereas levels of estrogen receptor 1 (ESR1), total progesterone receptor (PGR), and progesterone receptor B (PGR B) were significantly lower in endometriotic versus endometrial stromal cells. Because ESR2 displayed the most striking levels of differential expression between endometriotic and endometrial cells, and the mechanisms for this difference are unknown, we tested the hypothesis that alteration in DNA methylation is a mechanism responsible for severely increased ESR2 mRNA levels in endometriotic cells. We identified a CpG island occupying the promoter region (-197/+359) of the ESR2 gene. Bisulfite sequencing of this region showed significantly higher methylation in primary endometrial cells (n = 8 subjects) versus endometriotic cells (n = 8 subjects). The demethylating agent 5-aza-2'-deoxycytidine significantly increased ESR2 mRNA levels in endometrial cells. Mechanistically, we employed serial deletion mutants of the ESR2 promoter fused to the luciferase reporter gene and transiently transfected into both endometriotic and endometrial cells. We demonstrated that the critical region (-197/+372) that confers promoter activity also bears the CpG island, and the activity of the ESR2 promoter was strongly inactivated by in vitro methylation. Taken together, methylation of a CpG island at the ESR2 promoter region is a primary mechanism responsible for differential expression of ESR2 in endometriosis and endometrium. These findings may be applied to a number of areas ranging from diagnosis to the treatment of endometriosis.

    • "Once the lesions are established, local estrogen production begins through endometrial cell expression of aromatase p450 (Noble et al., 1996) and a reduction in 17b-hydroxysteroid dehydrogenase type II (Zeitoun et al., 1998). The overexpression of estrogen receptor (ER)b in endometriotic stromal cells also alters their behaviour leading to a reduction in the expression of ERa (Xue et al., 2007; Trukhacheva et al., 2009) and possibly of progesterone receptors (PRs) (Bulun et al., 2010). Finally, neuroangiogenesis leads to the infiltration of nerve fibres and blood vessels (Asante and Taylor, 2011) that supply nutrients and remove waste, as well as secreting neurogenic compounds (Sanfilippo et al., 1992) that interact with endometriotic lesions (McKinnon et al., 2013). "
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    ABSTRACT: BACKGROUND Endometriosis, the growth of endometrial tissue outside the uterine cavity, is associated with chronic pelvic pain, subfertility and an increased risk of ovarian cancer. Current treatments include the surgical removal of the lesions or the induction of a hypoestrogenic state. However, a reappearance of the lesion after surgery is common and a hypoestrogenic state is less than optimal for women of reproductive age. Additional approaches are required. Endometriosis lesions exist in a unique microenvironment characterized by increased concentrations of hormones, inflammation, oxidative stress and iron. This environment influences cell survival through the binding of membrane receptors and a subsequent cascading activation of intracellular kinases that stimulate a cellular response. Many of these kinase signalling pathways are constitutively activated in endometriosis. These pathways are being investigated as therapeutic targets in other diseases and thus may also represent a target for endometriosis treatment.
    No preview · Article · Jan 2016 · Human Reproduction Update
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    • "of steroid hormone receptors, have also been identified in endometriotic lesions (Wu et al. 2005, Kim et al. 2007, Xue et al. 2007a,b). Endometriosis causes infertility in up to 50% of patients and affects 20–40% of women seeking infertility evaluation (Berube et al. 1998, Giudice 2010). "
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    ABSTRACT: Endometriosis is associated with infertility and debilitating chronic pain. Abnormal epigenetic modifications in the human endometrium have recently been implicated in the pathogenesis of this condition. However, whether an altered epigenetic landscape contributes to pathological changes in the ovary is unknown. Using an established baboon endometriosis model, early and late stage epigenetic changes in the ovary were investigated. Transcript profiling of key chromatin modifying enzymes using pathway focused PCR arrays on ovarian tissue from healthy control animals and at 3 and 15 months of endometriosis revealed dramatic changes in gene expression in a disease duration-dependent manner. Ingenuity pathway analysis indicated that transcripts for chromatin-remodeling enzymes associated with reproductive system disease and cancer development were abnormally regulated, most prominently the arginine methyltransferases Carm1, Prmt2 and Prmt8. Down-regulation of CARM1 protein expression was also detected in the ovary, fully-grown oocytes and eutopic endometrium following 15 months of endometriosis. Sodium bisulfite sequencing revealed DNA hypermethylation within the Prmt8 promoter, suggesting that deregulated CpG methylation may play a role in transcriptional repression of this gene. These results demonstrate that endometriosis is associated with changes of epigenetic profiles in the primate ovary and suggest that arginine methyltransferases play a prominent role in mediating the ovarian response to endometriosis. Due to the critical role of CARM1 in nuclear receptor mediated transcription and maintenance of pluripotency in the cleavage stage embryo, our results suggest that epigenetic alterations in the ovary may have functional consequences for oocyte quality and the etiology of infertility associated with endometriosis.
    Full-text · Article · Jul 2015 · Reproduction
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    • "Trichostatin A (HDAC pan inhibitor) inhibits NFκB signaling, COX-2 expression, and cell proliferation ; by contrast, increases expression of PR-B and E-cadherin in endometriotic cells in vitro (Wu and Guo, 2007, 2008; Wu et al., 2007, 2008). The DNA methylation inhibitor 5-Aza differentially regulates expression of ERβ and SF-1 in endometrial and endometriotic cells (Izawa et al., 2008; Xue et al., 2007a, 2007b). Although PGE2 plays an important role in the pathogenesis of endometriosis (Banu et al., 2008; Chuang et al., 2010; Cobellis et al., 2004; Laschke et al., 2007; Matsuzaki et al., 2004; Olivares et al., 2008; Wu et al., 2007, 2010), the underlying epigenetic mechanisms of PGE2 action are largely unknown. "
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    ABSTRACT: Endometriosis is an inflammatory gynecological disease of reproductive-age women. The prevalence of endometriosis is 5~10% in reproductive-age women. Modern medical treatments are directed to inhibit the action of estrogen in endometriotic cells. However, hormonal therapies targeting estrogen can be prescribed only for a short time because of their undesirable side effects. Recent studies from our laboratory, using endometriotic epithelial cell line 12Z and stromal cell line 22B derived from red lesion, discovered that selective inhibition of prostaglandin E2 (PGE2) receptors EP2 and EP4 inhibits adhesion, invasion, growth, and survival of 12Z and 22B cells by modulating integrins, MMPs and TIMPs, cell cycle, survival, and intrinsic apoptotic pathways, suggesting multiple epigenetic mechanisms. The novel findings of the present study indicate that selective pharmacological inhibition of EP2 and EP4: (i) decreases expression of DNMT3a, DNMT3b, H3K9me3, H3K27me3, SUV39H1, HP1a, H3K27, EZH2, JMJD2a, HDAC1, HDAC3, MeCP2, CoREST and Sin3A; (ii) increases expression of H3K4me3, H3H9ac, H3K27ac; and (iii) does not modulate the expression of DNMT1, hSET1, LSD1, MBD1, p300, HDAC2, and JMJD3 epigenetic machinery proteins in an epithelial and stromal cell specific manner. In this study, we report for the first time that inhibition of PGE2-EP2/EP4 signaling modulates DNA methylation, H3 Histone methylation and acetylation, and epigenetic memory machinery proteins in human endometriotic epithelial cells and stromal cells. Thus, targeting EP2 and EP4 receptors may emerge as long-term nonsteroidal therapy for treatment of active endometriotic lesions in women. Copyright © 2015. Published by Elsevier Ireland Ltd.
    Full-text · Article · Apr 2015 · Molecular and Cellular Endocrinology
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