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

Abstract

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.