Deregulation of tissue homeostasis in endometria from patients with polycystic ovarian syndrome with and without endometrial hyperplasia

Objective.To study the proteins involved in endometrial homeostasis in PCOS women.Methods.Protein expression of Ki67, Bcl-2, Bax, Pro-Caspase-3 and Caspase-3 by immunohistochemistry and/or Western blot, and DNA fragmentation using in situ 3′-end labeling of apoptotic cells, was measured in 9 samples of normal endometrium (NE), 12 PCOS endometria without treatment (PCOSE), 7 endometria from PCOS women with endometrial hyperplasia (HPCOSE) and 9 endometria from patients with endometrial hyperplasia (HE).Results.Cell proliferation was higher in epithelium from PCOSE (P < 0.05), HPCOSE and HE vs NE. A higher Bcl-2/Bax relative ratio in PCOSE and HPCOSE was observed, in absence of active Caspase-3 and scarce DNA fragmentation in the four groups of endometria studied.Conclusion.As the apoptosis was scarce in all of the groups studied, endometrial homeostasis deregulation in PCOS could be a result of increased proliferation. Therefore, the onset of endometrial hyperplasia in PCOS endometrium could be linked to inadequate cell proliferation, and concomitantly to inadequate cell survival.