Androgen receptor inhibits the prolfieration of estrogen receptor-positive bre ast cancer cells / 医学研究生学报

ABSTRACT

Objective Androgen receptor ( AR) is extensively expressed in breast cancer and influences the proliferation of the malignant cells.Our study aimed to investigate the effect of AR on estrogen receptor (ER)-positive breast cancer. Methods ER-positive MCF-7 breast cells were exposed to various concentrations of agonist dihydrotestosterone ( DHT) or antagonist bicalutamide or left untreated .Then the proliferation and apoptosis of the cells were determined by MTT assay , cell counting , and flow cytometry , and the expressions of the proteins related to cell cycle regulation were detected by Western blot . Results The relative gray value of AR was significantly increased in the DHT group (1.055 ±0.020) but decreased in the bicalutamide group (0.705 ±0.010) as com-pared with the blank control (0.795 ±0.020) (both P<0.05).Flow cytometry showed that the early apoptosis rate of the breast cancer cells was markedly higher in the DHT group ([51.20 ±0.312]%) but lower in the bicalutamide group ([2.410 ±0.367]%) than in the blank control ([3.540 ±0.375]%) (both P<0 .01). In comparison with the control group , the expressions of the p53, p73 and p21 proteins in the MCF-7 cells were remarkably up-regulated in the DHT group but down-regulated in the bicalutamide group ( both P<0.05). Conclusion AR inhibits the proliferation of ER-posi-tive breast cancer cells , which suggests that it may be a potential ther-apeutic target for ER-positive breast cancer .