MicroRNA-320b抑制PI3K-AKT信号通路调控胃癌细胞系MGC-803和MKN45的增殖作用

Role of microRNA-320b regulating cell proliferation through inhibition of PI3K-AKT signaling pathway in MGC-803 and MKN45 cells

目的:探究microRNA-320b(miR-320b)在胃癌组织中的表达及其对胃癌细胞系增殖和凋亡的影响。方法:使用Real-time PCR法检测miR-320b在66例胃癌患者癌组织及其癌旁组织中的表达,分析胃癌患者癌组织miR-320b表达与临床特征的关系。检测胃癌细胞系MGC-803,MKN45和正常胃上皮细胞GES-1中miR-320b的表达。采用miR-320b mimics和miR-320b inhibitor转染胃癌细胞系MGC-803和MKN45,分别使用CCK-8实验和流式细胞仪检测miR-320b对细胞增殖和凋亡的影响,运用蛋白免疫印迹法检测miR-320b干扰和过表达对PI3K-AKT信号通路激活的影响。结果:胃癌组织中miR-320b表达显著低于癌旁组织(P<0.001),胃癌细胞系MGC-803和MKN45中miR-320b表达显著低于胃上皮细胞系GES-1(P<0.01)。与转染miR-NC比较,转染miR-320b mimics的MGC-803和MKN45细胞增殖显著降低,细胞凋亡增加,而转染miR-320b inhibitor的MGC-803和MKN45细胞增殖显著增加,细胞凋亡减少。与转染miR-NC比较,转染miR-320b mimics的MGC-803和MKN45细胞p-PI3K和p-AKT蛋白水平显著降低,而转染miR-320b inhibitor的MGC-803和MKN45细胞p-PI3K和p-AKT蛋白水平显著增加。结论:miR-320b可能作为抑癌基因在胃癌中发挥作用,并对胃癌细胞的增殖和凋亡具有显著影响。

Objective:To investigate the expression of microRNA-320b(miR-320b)in gastric cancer and its effect in cell proliferation and apoptosis.Methods:The expression of miR-320b in gastric cancer and para-carcinoma tissues in 66 patients was detected by real time PCR,and the relationship between the expression of miR-320b and clinical characteristics was analyzed.The expression of miR-320b in gastric cancer cell lines MGC-803,MKN45 and normal gastric epithelial cells GES-1 was detected.Gastric cancer cell lines MGC-803 and MKN45 were transfected with miR-320b mimics and miR-320b inhibitor.The effects of miR-320b on cell proliferation and apoptosis were detected by CCK-8 experiment and flow cytometry,respectively.The effects of miR-320b interference and overexpression on PI3K-AKT signaling pathway were detected by Western blotting.Results:The expression of miR-320b in gastric cancer tissues was significantly lower than that in para-carcinoma tissues(P<0.001),and the expression of miR-320b in gastric cancer cell lines MGC-803 and MKN45 was significantly lower than that in gastric epithelial cell line GES-1(P<0.01).Compared with miR-NC transfection,the proliferation of MGC-803 and MKN45 cells transfected with miR-320b mimics significantly decreased,and apoptosis increased.However,the proliferation of MGC-803 and MKN45 cells transfected with miR-320b inhibitor significantly increased,and apoptosis decreased.The expressions of p-PI3K and p-AKT protein in MGC-803 and MKN45 cells transfected with miR-320b mimics were significantly lower than those transfected with miR-NC.The expressions of p-PI3K and p-AKT protein in MGC-803 and MKN45 cells transfected with miR-320b inhibitor increased significantly than those transfected with miR-NC.Conclusion:MiR-320b may play a role as a tumor suppressor gene in gastric cancer and has a significant effect on the proliferation and apoptosis of gastric cancer cells.