ECT2-siRNA转染对肺腺癌A549细胞周期分布和凋亡的影响

Effects of ECT2-siRNA transfection on cell cycle distribution and apoptosis of lung adenocarcinoma A549 cells

目的:探讨ECT2-siRNA转染对肺腺癌A549细胞周期分布和凋亡的影响及其机制。方法:将体外培养的A549细胞分为空白组(未转染)、阴性对照组(转染阴性对照NC-siRNA)和干扰组(转染ECT2-siRNA),采用PI染色检测细胞周期分布,采用Annexin V-FITC和PI双染法检测凋亡,用Western blot检测细胞中ECT2、Cyclin D1、P53和Cleaved Caspase-3蛋白的表达。结果:干扰组细胞中ECT2蛋白的表达水平低于空白组和阴性对照组(P <0. 05)。与其他2组相比,干扰组S期和G2/M期细胞百分比降低,而G0/G1期细胞百分比和细胞凋亡率均升高(P <0. 05),Cyclin D1蛋白的表达水平降低,而P53和Cleaved Caspase-3蛋白的表达水平升高(P <0. 05)。结论:靶向沉默ECT2的表达可诱导A549细胞周期阻滞和凋亡,其作用机制可能与下调Cyclin D1,上调P53、Cleaved Caspase-3蛋白的表达有关。

Aim:To investigate the effects of ECT2-siRNA transfection on cell cycle distribution and apoptosis of lung adenocarcinoma A549 cells.Methods::A549 cells cultured in vitro were divided into blank group(untransfected),negative control group(transfected with negative control NC-siRNA)and interference group(transfected with ECT2-siRNA).The cell cycle distribution and apoptosis were detected by PI staining and Annexin V-FITC and PI staining,respectively.The expressions of ECT2,CyclinD1,P53 and Cleaved Caspase-3 protein were detected by Western blot.Results:The expression of ECT2 protein in the interference group was significantly lower than those in the blank group and negative control group(P<0.05).Compared with the other 2 groups,the percentage of cells at S phase and G2/M phase decreased significantly in the interference group,while the percentage of cells at G0/G1 phase and apoptotic rate increased significantly(P<0.05);at the same time,the expression level of CyclinD1 protein in the interference group was significantly lower,while the expression levels of P53 and Cleaved Caspase-3 protein were higher(P<0.05).Conclusion:ECT2-siRNA transfection could induce cell cycle arrest and apoptosis in A549 cells,and its mechanism may be related to down-regulation of CyclinD1 and up-regulation of P53 and Cleaved Caspase-3 protein expression.