盐霉素及mTOR信号通路对前列腺癌DU145干细胞的影响

摘要

目的 探讨盐霉素对前列腺癌DU145干细胞的影响及其可能的机制,为盐霉素的临床应用提供理论依据.方法 盐霉素处理DU145细胞,以ALDH为肿瘤干细胞标记物,用流式细胞仪检测处理后ALDH阳性的DU145干细胞的百分比.盐霉素处理DU145细胞后,用Western Blot法检测mTOR信号通路相关蛋白m-TOR、p-70s6k、p-p70s6、p-s6等的表达变化.盐霉素结合mTOR信号通路抑制剂雷帕霉素处理DU145细胞,利用流式细仪检测ALDH阳性的DU145干细胞百分比.结果 盐霉素显著性抑制ALDH阳性的DU145干细胞(抑制率为77.78%),是紫杉醇的2倍(抑制率为38.64%).盐霉素抑制mTOR信号通路相关分子m-TOR、p-70s6k、p-p70s6、p-s6等蛋白的表达,具有时间依赖性和剂量依赖性.盐霉素结合雷帕霉素能够抑制ALDH阳性的DU145干细胞比例(抑制率为77.95%).结论 盐霉素可能通过抑制mTOR通路信号来发挥抑制肿瘤干细胞的作用.%Objective To investigate the effect of salinomycin on cancer stem cell formation of prostate cancer cell line DU145 and its possible mechanisms,providing theoretical basis for the clinical application of salino-mycin. Methods (1)DU145 cells were treated with salinomycin. The percentage of ALDH+cells,which was used as the marker of cancer stem cells,was detected by flow cytometry.(2)After treated with salmonin,DU145 cells were subjected to Western-Blot analysis for the expression of mTORsignal pathway-related proteins such as p-70s6k, p-p70s6,p-s6 and so on. 3)DU145 cells were treated with salinomycin combined with mTOR signal pathway inhibi-tor rapamycin,and the ALDH+cancer stem cells were detected using flow cytometer. Results (1)Salmonomycin significantly inhibited ALDH-positive cancer stem cells in DU145cell line(inhibition rate in 77.8%),which was twice as high as that of traditional anticancer drug paclitaxel(which has a inhibition rate of 38.64%). This results suggesting that salinomycin would have the effect of inhibiting cancer stem cells. (2)The expression ofm-TOR p-70s6k,p-p70s6 and p-s6 in mTOR signaling pathway was inhibited by salinomycin in a time-dependent and dose-dependent manner,suggesting that salinomycin would inhibite mTOR signaling pathway.(3)Salinomycin combined with rapamycin can decrease the proportion of ALDH-positive DU145 cancer stem cells(inhibition rate in 77.95%), suggesting that salinomycin may inhibit ALDH-positive DU145 stem cells through the mTOR signaling pathway. Conclusion Salinomycin may play an important role in inhibiting cancer stem cells by inhibiting mTOR pathway signaling.