摘要目的 探讨微小RNA (microRNA)-577对胃癌细胞功能的影响,并讨论其可能的作用机制.方法 通过实时荧光定量PCR检测miRNA-577在胃癌细胞SGC-7901和正常胃黏膜细胞中的表达水平.将转染miRNA-577病毒的SGC-7901细胞作为实验组,转染空载体组为阴性对照组,PCR检测两组细胞的miRNA-577表达水平.通过Transwell小室法检测两组细胞的迁移侵袭能力,MTT试验检测两组细胞的增殖能力,流式细胞术检测细胞周期.Western blot法检测细胞周期蛋白依赖性激酶4(CDK4)在两组细胞中的蛋白表达水平.结果 胃癌SGC-7901细胞的miRNA-577表达量明显低于正常胃黏膜上皮细胞(P＜0.01).PCR验证实验组细胞的miRNA-577的表达量较阴性对照组明显上升(P＜0.01).转染miRNA-577的细胞增殖明显减慢(P＜0.05),G1期细胞比例显著增加(P＜0.01).实验组细胞的CDK4表达明显低于对照组(P＜0.01).结论 miRNA-577在胃癌细胞中低表达,可能通过下调CDK4的表达,抑制胃癌细胞SGC-7901的增殖.

abstractsObjective To investigate the effects of miRNA-577 on the cell proliferation and migration of human gastric cancer cell line SGC-7901,and to explore its mechanism.Methods The expression levels of miRNA-577 in human gastric mucosal epithelial cells GES (gastric epithelial cells) and human gastric cancer cell line SGC-7901 were detected by real-time polymerase chain reaction (RT-PCR).Gastric cancer SGC-7901 cells were infected with transfected with miRNA-577 or control miRNA vector.Transwell assay,methyl thiazolyl tetrazolium (MTT) test,and flow cytometry were used in both groups.Western blot was used to detect the level of cyclin dependent kinase 4 (CDK4) protein.Results Compared to GES,the expression level of miRNA-577 was decreased significantly in gastric cancer cell lines (P ＜ 0.01).The ratio of proliferation inhibition,and cells arrested at G1/G0 phase were increased significantly in miRNA-577 lentiviral infected group compared to the negative control group (P ＜ 0.05).CDK4 protein expression was lower in the miRNA-577 lentiviral infected group(P ＜ 0.01).Conclusions miRNA-577 has lower expression level in gastric caner cell line SGC-7901.miRNA-577 can inhibit proliferation,induce cell cycle arrest of gastric caner cell line SGC-7901,maybe through downregulating expression of CDK4.