miRNA-577对胃癌细胞生物学行为的影响

The effects of miRNA-577 on the function of human gastric cancer cells

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，MTY试验检测两组细胞的增殖能力，流式细胞术检测细胞周期。Westernblot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。

Objective 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 ceils 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 （MTY） 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 rati- o of proliferation inhibition, and cells arrested at G1/GO 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 expres- sion 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.