The identification of two subgroups of obese women with differing endometrial proliferation levels: Potential consequences in the development of endometrial cancer

Abstract

Enhanced endometrial proliferation correlates obesity to type-I (estrogen-dependent) endometrial cancer (EC). Our aim was to distinguish obese women (without EC) with differing endometrial proliferation. Endometrial and blood samples were obtained from normal-weight and obese women without EC. Type-I EC samples were obtained from obese patients. On measuring endometrial proliferation (Ki67 and phosphorylated histone H3 (p-H3)), two groups of obese women without EC were identified: obeseHigh Proliferating (O HP) and obeseLow Proliferating (OLP). Increased Ki67 (88.5%, P<0.001), p-H3 (62.6%, P<0.01), 17Β-estradiol/ progesterone ratio (46.3%, P<0.01) and endometrial estrogen receptor alpha (ERα) (82.2%, P<0.001) were observed in OHP compared with OLP patients. ECs possessed similar ERα and enhanced proliferation as OHP, suggesting that OHP women are at higher risk of type-I EC. OLP women were indistinguishable from normal-weight women regarding these determinants of endometrial proliferat