Hormone replacement therapy use dramatically increases breast oestrogen receptor expressions in obese postmenopausal women

Abstract

Background: It is known that use of hormone replacement therapy (HRT) by postmenopausal women increases the risk of breast cancer. Method: In this study, oestrogen receptor (ER)-α expression is examined using standard immunoperoxidase technique. Results: Normal breast samples of 11 Australian postmenopausal women have been included in the ER-α study; the result showed a strong correlation (r2=0.80) between ER-α expression in normal breast epithelial cells and body mass index (BMI) in normal women who currently use HRT. Conclusion: This finding confirms that the possibility of increased risk of breast cancer associated with increased ER-α expression in normal breast epithelial cells, in turn associated with high BMI and the use of HRT.