TY - JOUR
T1 - Estrogen receptor (ER) β regulates ERα expression in stromal cells derived from ovarian endometriosis
AU - Trukhacheva, Elena
AU - Lin, Zhihong
AU - Reierstad, Scott
AU - Cheng, You Hong
AU - Milad, Magdy
AU - Bulun, Serdar E.
N1 - Funding Information:
This work was supported by National Institutes of Health Grants HD38691 and HD40093 and by the Friends of Prentice (to S.E.B.).
PY - 2009/2
Y1 - 2009/2
N2 - Context: Estradiol and its nuclear receptors, estrogen receptor (ER) α and ERβ, play critical roles in endometrium and endometriosis. Levels of ERβ, due to pathological hypomethylation of its promoter, are significantly higher in endometriotic vs. endometrial tissue and stromal cells, whereas ERα levels are lower in endometriosis. Estradiol regulates ERα gene expression via its alternatively used promoters A, B, and C. Objective: The aim of the study was to determine whether high levels of ERβ in endometriotic stromal cells from ovarian endometriomas regulate ERα gene expression. Results: ERβ knockdown significantly increased ERα mRNA and protein levels in endometriotic stromal cells. Conversely, ERβ overexpression in endometrial stromal cells decreased ERα mRNA and protein levels. ERβ knockdown significantly decreased proliferation of endometriotic stromal cells. Chromatin immunoprecipitation assays demonstrated that estradiol enhanced ERβ binding to nonclassical activator protein 1 and specificity protein 1 motifs in the ERα gene promoters A and C and a classic estrogen response element in promoter B in endometriotic stromal cells. Conclusions: High levels of ERβ suppress ERα expression and response to estradiol in endometrial and endometriotic stromal cells via binding to classic and nonclassic DNA motifs in alternatively used ERα promoters. ERβ also regulates cell cycle progression and might contribute to proliferation of endometriotic stromal cells. We speculate that a significantly increased ratio of ERβ:ERα in endometriotic tissues may also suppress progesterone receptor expression and contribute to progesterone resistance. Thus, ERβ may serve as a significant therapeutic target for endometriosis.
AB - Context: Estradiol and its nuclear receptors, estrogen receptor (ER) α and ERβ, play critical roles in endometrium and endometriosis. Levels of ERβ, due to pathological hypomethylation of its promoter, are significantly higher in endometriotic vs. endometrial tissue and stromal cells, whereas ERα levels are lower in endometriosis. Estradiol regulates ERα gene expression via its alternatively used promoters A, B, and C. Objective: The aim of the study was to determine whether high levels of ERβ in endometriotic stromal cells from ovarian endometriomas regulate ERα gene expression. Results: ERβ knockdown significantly increased ERα mRNA and protein levels in endometriotic stromal cells. Conversely, ERβ overexpression in endometrial stromal cells decreased ERα mRNA and protein levels. ERβ knockdown significantly decreased proliferation of endometriotic stromal cells. Chromatin immunoprecipitation assays demonstrated that estradiol enhanced ERβ binding to nonclassical activator protein 1 and specificity protein 1 motifs in the ERα gene promoters A and C and a classic estrogen response element in promoter B in endometriotic stromal cells. Conclusions: High levels of ERβ suppress ERα expression and response to estradiol in endometrial and endometriotic stromal cells via binding to classic and nonclassic DNA motifs in alternatively used ERα promoters. ERβ also regulates cell cycle progression and might contribute to proliferation of endometriotic stromal cells. We speculate that a significantly increased ratio of ERβ:ERα in endometriotic tissues may also suppress progesterone receptor expression and contribute to progesterone resistance. Thus, ERβ may serve as a significant therapeutic target for endometriosis.
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U2 - 10.1210/jc.2008-1466
DO - 10.1210/jc.2008-1466
M3 - Article
C2 - 19001520
AN - SCOPUS:59749086833
VL - 94
SP - 615
EP - 622
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 2
ER -