Promoter methylation regulates estrogen receptor 2 in human endometrium and endometriosis.
ABSTRACT 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.
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ABSTRACT: PROBLEM: To search for molecular markers of endometriosis the following polymorphisms: p53 codon 72 Pro (apoptosis), TNF alpha-308 (inflammation), VEGF-1164AA (angiogenesis), and SOD2 (oxidative stress) were investigated. METHOD OF STUDY: Forty-two women-24 with surgically proven endometriosis and 18 with no endometriosis found at the time of laparoscopy-had buccal swabs taken for DNA analyses of 4 gene polymorphisms including p53codon72, TNF-308 G/A, VEGF-1154G/A, SOD Ala16Val DNA. The frequencies of genotypes and alleles of these polymorphisms were compared between women with and without endometriosis. RESULTS: No specific gene mutation differences for the four genes tested nor differences in the frequencies of heterozygous and homozygous mutations were found between patients with endometriosis and controls. In addition, no differences in allelic frequencies of the four genetic polymorphisms were observed between patients with endometriosis and control. CONCLUSION: Endometriosis is not associated with gene mutations for p53codon72, TNF-308 G/A, VEGF-1154G/A, SOD Ala16Val.American Journal Of Reproductive Immunology 11/2012; · 3.32 Impact Factor
- Journal of obstetrics and gynaecology: the journal of the Institute of Obstetrics and Gynaecology 11/2012; 32(8):816. · 0.43 Impact Factor
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ABSTRACT: BACKGROUND: The resistance of endometriotic tissue to progesterone can be explained by alterations in the distribution of progesterone receptor (PR) and estrogen receptor (ER) isoforms. The aims of this study were to examine the expressions of PR-A, PR-B, ERalpha and ERbeta in endometrioma and assess whether these expressions are affected by dienogest or leuprolide acetate (LA) treatment. METHODS: We enrolled 60 females, including 43 patients with endometriosis (14 who received no medical treatment, 13 who received dienogest and 16 who received LA before undergoing laparoscopic surgery) and 17 patients with leiomyoma. The expression levels of PR and ER isoforms in eutopic and ectopic endometrium were assayed with quantitative real-time PCR, and confirmed with immunohistochemistry. RESULTS: A decreased PR-B/PR-A ratio and an increased ERbeta/ERalpha ratio were demonstrated in ectopic endometrium derived from females with endometriosis compared with the ratios observed in eutopic endometrium obtained from females without endometriosis. Although LA treatment did not affect the PR-B/PR-A and ERbeta/ERalpha ratios, dienogest treatment increased the PR-B/PR-A ratio and decreased the ERbeta/ERalpha ratio in patients with endometriomas. CONCLUSIONS: Dienogest may improve progesterone resistance in endometriotic tissue by increasing the relative expressions of PR-B and PR-A, and decreasing the relative expressions of ERbeta and ERalpha.Journal of Ovarian Research 11/2012; 5(1):31. · 2.43 Impact Factor