格尔德霉素对人卵巢癌细胞SKOV3增殖和凋亡的影响及其机制探讨

Effects of geldanamycin on cell proliferation and apoptosis of human ovarian cancer cell line SKOV3 and their mechanism

目的:研究格尔德霉素(geldanamycin,GA)对人卵巢癌SKOV3细胞的体外抑制作用,探讨GA抑制SKOV3细胞增殖及诱导其凋亡的可能机制。方法:MTT法检测GA单独或联合顺铂(cisplatin)对SKOV3细胞的增殖抑制作用;FCM法检测GA作用后SKOV3细胞周期及凋亡率的变化;分别应用免疫细胞化学法(immunocytochemistory,ICC)和FCM法检测GA处理SKOV3细胞48h后细胞内Akt、Raf-1蛋白的表达变化。结果:GA对SKOV3细胞的体外增殖可产生明显的抑制作用(P<0.05),该作用随着GA浓度的增高和作用时间的延长而增强。而且,GA可增强顺铂对SKOV3细胞的增殖抑制作用,在一定浓度范围内随着GA浓度的增高,两药联合应用对SKOV3细胞的增殖抑制作用越强。经0～2000nmol/L GA作用SKOV3细胞48h后,G2/M期细胞逐渐增多,细胞凋亡率也显著升高(P<0.05)。ICC和FCM法检测结果均表明,经0～2000nmol/L GA处理48h后,SKOV3细胞中Akt、Raf-1蛋白的表达水平随着药物浓度增高而逐渐降低(P<0.05)。结论:GA能够对卵巢癌SKOV3细胞产生明显的体外增殖抑制作用,并诱导其凋亡,其作用机制可能与下调卵巢癌细胞中Akt和Raf-1蛋白表达相关。

Objective： To investigate the cytotoxic effects of geldanamycin on human ovarian cancer SKOV3 cells, and to explore the possible mechanisms of apoptosis and cell proliferation inhibition of SKOV3 cells induced by geldanamycin. Methods： MTT method was performed to evaluate the inhibitory effects of geldanamycin alone or in combination with cisplatin on proliferation of SKOV3 cells. Cell cycle and apoptosis rate of SKOV3 cells treated with geldanamycin were detected by flow cytometry. The expressions of Akt and Raf-1 proteins were examined by immunocytochemistry and flow cytometry. Results： The proliferation of SKOV3 cells was inhibited by different concentrations of geldanamycin in a time- and dose-dependent manners （P〈0.05）. Different concentrations of geldanamycin strengthened the inhibitory effect of cisplatin on proliferation of SKOV3 cells, and this inhibitory effect was strengthened with the increased concentration of geldanamycin within a certain concentration range. The apoptosis rate of SKOV3 cells was raised up gradually after treatment with 0-2 000 nmol/L geldanamycin for 48 h, and the number of cells in G2/M phase was increased significantly （P〈0.05）. The results of immunocytochemistry and flow cytometry showed that the expressions of Akt and Raf-1 proteins in SKOV3 cells induced by geldanamycin were significantly down-regulated in a dose-dependent manner （P〈 0.05）. Conclusion： Geldanamycin can inhibit the cell proliferation and induce the apoptosis of human ovarian cancer SKOV3 cells in vitro, which may be associated with downregulation of the expressions of Akt and Raf-1 proteins.