Evaluation of steroid receptors, coregulators, and molecules associated with uterine receptivity in secretory endometria from untreated women with polycystic ovary syndrome

ObjectiveTo evaluate gene and protein expression of steroid receptors, nuclear receptor coregulators, and uterine receptivity markers in midsecretory phase endometria from untreated women with polycystic ovary syndrome (PCOS).DesignCase-control study.SettingHospital research unit.Patient(s)Eight patients with PCOS and eight fertile women of similar age to those with PCOS.Intervention(s)Endometrial samples were obtained from women with PCOS (PCOSE) and normal (NE) women during the midsecretory phase of the menstrual cycle.Main Outcome Measure(s)Expression studies (immunohistochemistry, reverse transcription-polymerase chain reaction [RT-PCR] and Western blot).Result(s)Endometria from PCOS exhibit higher levels of messenger RNA (mRNA) and protein for estrogen receptor α and coactivators than NE. Epithelial cells had a greater expression of progesterone receptor in PCOSE, whereas, no differences were observed in gene and protein expression of the nuclear corepressor (NcoR) and the antiadhesion molecule mucin type-1 (MUC-1) between PCOSE and NE. Immunodetection for the coactivator ARA70 was higher in PCOSE than in NE; in contrast, expression of β3-integrin in epithelia was lower in PCOSE than in control endometria.Conclusion(s)The higher response to steroid hormones of endometria from untreated PCOS-women induces diminished expression of β3 integrin, which partially explain implantation failure in PCOS patients.