熊果苷对膀胱癌EJ-1细胞增殖的影响及其机制研究

Effect of Arbutin on Proliferation of Bladder Cancer EJ-1 Cells and Its Mechanism

【目的】探讨熊果苷对膀胱癌EJ-1细胞增殖的影响及其机制研究。【方法】采用MTT法观察不同质量浓度(10、20、50、100、500μg/mL)及不同作用时间(24、48、72、96 h)熊果苷对EJ-1细胞增殖能力的影响,流式细胞术观察100μg/mL熊果苷对EJ-1细胞周期及凋亡的影响,蛋白免疫印迹(Western blot)法观察熊果苷对EJ-1细胞外信号调节激酶(ERK)、磷酸化ERK(p-ERK)、Cyclin D1、p21蛋白表达的影响。【结果】100μg/mL熊果苷对EJ-1细胞增殖的抑制作用最佳,且呈时间依赖性。细胞阻滞于G2/M期。100μg/mL熊果苷作用96 h的EJ-1细胞增殖指数(PI)下降,与处理24~48 h的细胞PI比较,差异有统计学意义(P <0.05)。亚G1峰值逐渐升高,96 h时最为明显(P<0.05)。Western blot结果显示:与同组0 d比较,作用24、48、72、96 h后, p-ERK蛋白表达水平均降低(P> 0.05),呈逐渐下降后升高的趋势;ERK蛋白表达水平均降低,但差异无统计学意义(P> 0.05);Cyclin D1蛋白表达水平均升高(P> 0.05),呈逐渐升高后下降的趋势;p21蛋白表达水平随时间延长逐渐升高,于96 h差异有统计学意义(P <0.05)。【结论】熊果苷可抑制膀胱癌EJ-1细胞的增殖,其机制可能与抑制ERK和p21蛋白的表达有关。

Objective To explore the effect of arbutin on the proliferation of bladder cancer EJ-1 cells and its mechanism. Methods The effect of arbutin at different concentrations(10,20,50,100,500 μg/mL)and at different treatment time(24, 48, 72, 96 h) on the cell cell proliferation of bladder cancer EJ-1 cells was observed by MTT. The effect of arbutin at 100 μg/mL on the cycle and apoptosis of EJ-1 cells was observed by flow cytometry. The effect of arbutin on the expression of extracellular signal-regulated kinase(ERK),phospho-ERK(p-ERK),Cyclin D1,and p21 in bladder cancer EJ-1 cells was observed by Western blotting method. Results Arbutin at 100 μg/mL had the strongest inhibitory effect on the proliferation of EJ-1 cells in a time-dependent manner. EJ-1 cells were blocked in G2/M period. The proliferation index(PI)of EJ-1 cells after arbutin treatment for 96 h was decreased,the difference being statistically significant as compared with that after arbutin treatment for 24 ~ 48 h(P < 0.05). The sub G1 peak value was gradually increased,especially at 96 h(P < 0.05). Western blotting results showed that compared with the same group at 0 h,the expression level of p-ERK was decreased after treatment for 24,48,72,96 h(P > 0.05) with the trend of gradually decreasing first and then increasing,the expression level of ERK was decreased but the difference was not significant(P > 0.05),the expression level of Cyclin D1 was increased(P > 0.05) with the trend of gradually increasing first and then decreasing, the expression level of p21 was gradually increased with the prolongation of time and was significantly different from that at 96 h(P < 0.05). Conclusion Arbutin can inhibit the proliferation of bladder cancer EJ-1 cells, and its mechanism is related with inhibiting the expression of ERK and p21 proteins.