In SilicoAnalysis Identifies a Novel Role for Androgens in the Regulation of Human Endometrial Apoptosis

Abstract

Context:The endometrium is a multicellular, steroid-responsive tissue that undergoes dynamic remodeling every menstrual cycle in preparation for implantation and, in absence of pregnancy, menstruation. Androgen receptors are present in the endometrium.Objective:The objective of the study was to investigate the impact of androgens on human endometrial stromal cells (hESC).Design:Bioinformatics was used to identify an androgen-regulated gene set and processes associated with their function. Regulation of target genes and impact of androgens on cell function were validated using primary hESC.Setting:The study was conducted at the University Research Institute.Patients:Endometrium was collected from women with regular menses; tissues were used for recovery of cells, total mRNA, or protein and for immunohistochemistry.Results:A new endometrial androgen target gene set (n = 15) was identified. Bioinformatics revealed 12 of these genes interacted in one pathway and identified an association with control of cell survival. Dynamic androgen-dependent changes in expression of the gene set were detected in hESC with nine significantly down-regulated at 2 and/or 8 h. Treatment of hESC with dihydrotestosterone reduced staurosporine-induced apoptosis and cell migration/proliferation.Conclusions:Rigorous in silico analysis resulted in identification of a group of androgen-regulated genes expressed in human endometrium. Pathway analysis and functional assays suggest androgen-dependent changes in gene expression may have a significant impact on stromal cell proliferation, migration, and survival. These data provide the platform for further studies on the role of circulatory or local androgens in the regulation of endometrial function and identify androgens as candidates in the pathogenesis of common endometrial disorders including polycystic ovarian syndrome, cancer, and endometriosis.

Regulation of androgen action during establishment of pregnancy

“…Functional studies confirmed that treatment of human primary ESCs in vitro with the potent androgen DHT significantly decreased cell proliferation and migration as well as AR-dependent inhibition of staurosporin-induced apoptosis (Marshall et al 2011). Similar effects on proliferation were observed in vitro with human primary endometrial epithelial cells treated with the weak androgen A4; A4 induced a dosedependent decrease in proliferation evident by decreased uptake of 3 H-thymidine and MKi67 expression, an effect that was reversed after co-incubation with the AR antagonist cyproterone acetate (Tuckerman et al 2000).…”

“…Although AR is expressed at low levels in endometrial epithelial cells during the secretory phase, the endometrium of women administered with the anti-progestin mifepristone exhibits an elevated expression of AR in epithelial and stromal cells (Slayden et al 2001, Narvekar et al 2004. Notably, analysis of full-thickness uterine biopsies demonstrates that AR immunoexpression in endometrial epithelial cells is increased following progesterone withdrawal at the time of menses, consistent with role for progestins in regulating the expression of AR (Marshall et al 2011). Following the establishment of pregnancy, immunohistochemistry studies have reported that AR is detected in decidual stromal cells and in endothelial cells lining endometrial arteries in first-trimester decidua (Horie et al 1992, Milne et al 2005, Critchley & Saunders 2009).…”

“…and validation of putative androgen target genes in human proliferative-phase ESCs identified that androgens regulate cellular proliferation and motility in the human endometrium (Marshall et al 2011). Functional studies confirmed that treatment of human primary ESCs in vitro with the potent androgen DHT significantly decreased cell proliferation and migration as well as AR-dependent inhibition of staurosporin-induced apoptosis (Marshall et al 2011).…”

“…Detection of AR is reported in several female tissues, including the ovaries, adipose, skin, brain, muscle and uterus (Kimura et al 1993). In the cycling human endometrium, AR is expressed predominantly in stromal fibroblasts of the basal and functional layers during the oestrogen-dominated proliferative phase, with receptor expression reduced during the progesterone-dominated secretory phase of the menstrual cycle (Mertens et al 2001, Marshall et al 2011. Although AR is expressed at low levels in endometrial epithelial cells during the secretory phase, the endometrium of women administered with the anti-progestin mifepristone exhibits an elevated expression of AR in epithelial and stromal cells (Slayden et al 2001, Narvekar et al 2004.…”

In situ androgen and estrogen biosynthesis in endometrial cancer: focus on androgen actions and intratumoral production

“…In the nonmalignant endometrium, AR was reported to be expressed in the endometrium throughout the menstrual cycle (Mertens et al 2001, Apparao et al 2002, Ito et al 2002, Marshall et al 2011, Gibson et al 2014. The status of AR immunoreactivity in stromal cells is higher than that of epithelial AR throughout the menstrual cycle (Apparao et al 2002).…”