靶向抑制胃癌细胞中TROP2基因的表达对胃癌细胞增殖及凋亡的影响研究

The effect of targeting inhibition of TROP2 gene expression on the proliferation and apoptosis of gastric cancer cells

目的探讨RNA干扰肿瘤相关钙信号传导因子2(TROP2)基因的表达对胃癌细胞增殖及凋亡的影响及机制。方法以人胃黏膜正常细胞GES-1作为对照,RT-PCR检测人胃癌SGC-7901、MNK-28、BGC-823细胞中TROP2 mRNA表达;TROP2 siRNA、Control siRNA转染SGC-7901细胞,不作任何处理的细胞作为空白对照组,48 h后Western blotting检测TROP2、Ki67、Cleaved caspase3、β-catenin、Cyclin D1蛋白表达;CCK8实验和流式细胞仪分别检测细胞的增殖及凋亡情况。结果 TROP2 mRNA在人胃癌SGC-7901、MNK-28、BGC-823细胞表达均显著高于GES-1细胞(P<0.01),TROP2基因在SGC-7901细胞中的表达最高,选择作为后续的研究对象;转染TROP2 siRNA后TROP2蛋白表达显著降低(P<0.01);与对照组及Control-siRNA组比较,TROP2-siRNA组细胞存活率及Ki67、β-catenin、Cyclin D1蛋白表达显著降低,细胞凋亡率及Cleaved caspase3蛋白表达显著升高(P<0.01)。结论RNA干扰抑制TROP2基因的表达可降低胃癌细胞的增殖及诱导细胞凋亡,其机制是下调Wnt/β-catenin信号通路。

Objective To investigate the effect and mechanism of RNA interference TROP2 on the proliferation and apoptosis of gastric cancer cell lines. Methods With human gastric mucosa normal GES-1 cells as control, the expression of TROP2 mRNA in human gastric cancer SGC-7901, MNK-28, BGC-823 cells was detected by RT-PCR; TROP2 siRNA, Control siRNA were transfected into SGC-7901 cells, and the cells without any treatment were as the control group, the expressions of TROP2, Ki67, Cleaved caspase3, β-catenin, Cyclin D1 protein after 48 hours were detected by Western blotting, CCK8 experiment and flow cytometry were used to detect the proliferation and apoptosis of cells. Results The expression of TROP2 mRNA in human gastric cancer SGC-7901 , MNK-28 and BGC-823 cells was significantly higher than that in GES-1 cells （P 〈 0.01 ）, the highest expression of TROP2 gene in SGC-7901 cells was selected as a follow-up study ; the expression of TROP2 protein after TROP2 siRNA transfeeted was significantly decreased （P 〈 0.01 ） ; compared with control group and Control-siRNA group, the cell survival rate and expressions of Ki67, β-catenin, Cyclin D1 protein in TROP2-siRNA group were significantly decreased, cell apoptosis rate and the expression of Cleaved caspase3 protein were significantly increased （P 〈 0. 01 ）. Conclusion Inhibition of TROP2 gene by RNA interference can decrease the proliferation and induce apoptosis of gastric cancer cells, the mechanism is to downregulate the Wnt/β- catenin signaling pathway.