Expression levels of BCL2 and MKI67 in endometrial polyps in postmenopausal women and their correlation with obesity.

Obesity is associated with numerous diseases, including endometrial disorders in postmenopausal women, such as adenocarcinoma, hyperplasias and endometrial polyps, and the risk of malignant transformation of these structures. The present study evaluated the influence of body mass index (BMI) on cell proliferation (BCL2 and MKI67) in endometrial polyps in postmenopausal women. A prospective cross-sectional study using immunohistochemical analysis of the expression of a cell proliferation marker (MKI67) and an anti-apoptotic gene (BCL2) in endometrial polyps in postmenopausal women was performed. The patients were divided into three groups depending on BMI: i) <24.9 kg/m (normal); ii) >25 and <29.9 kg/m (overweight); and iii) >30 kg/m (obese). The present study analyzed the expression of these markers in relation to polyp size, histological type and time since menopause in 38 patients. The interpretation of MKI67 and BCL2 expression accounted for the percentage of positive cells (scores): 1 (weak), <5% of cells showed expression; 2 (moderate), between 5 and 50%; and 3 (intense), >50%. Statistical analysis was performed using GraphPad InStat version 3.00 software. ANOVA was used to analyze BCL2 and MKI67 expression. A significance level of P<0.05 was adopted for rejecting the null hypothesis. There was greater glandular expression of MKI67 in obese women than in normal weight women (P=0.02) and greater expression of BCL2 in the stroma of polyps >2 cm (P=0.03). Hyperplastic polyps exhibited hyperexpression of MKI67 (P=0.04) compared with atrophic polyps. No difference in MKI67 and BCL2 expression was identified in the glands and stroma of polyps when comparing overweight and obese postmenopausal patients. The present findings suggest that BMI has an influence on proliferation markers (MKI67) in the polyps of postmenopausal women and that polyps >2 cm exhibit hyperexpression of BCL2 in the stroma.