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

OBJECTIVE: To 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).
DESIGN: Case-control study.
SETTING: Hospital 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 alpha 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 beta3-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 beta3 integrin, which partially explain implantation failure in PCOS patients.