H.pylori对胃癌患者miR-32表达的影响和对肿瘤细胞增殖活性的调控

Impact of H.pylori infection on miR-32 expression and proliferation of gastric cancer cells

目的探讨幽门螺旋杆菌(H.pylori)感染对胃癌患者miR-32表达的影响以及对肿瘤细胞增殖活性的调控机制。方法选取2017年7月至2018年4月期间在我校附属医院外科行根治性切除术的66例胃癌患者,采用体外细菌培养实验检测胃癌组织H.pylori感染情况;通过qRT-PCR法检测胃癌组织中CagAmRNA和miR-32表达情况,并分析miR-32表达与胃癌患者病理特征之间的关系;同时监测H.pylori体外刺激对SGC-7901细胞和GES-1细胞miR-32表达的影响。采用MTT法检测H.pylori感染对miR-32inhibitor转染SGC-7901细胞增殖活性的影响。结果经H.pylori菌株分离培养,47例胃癌患者癌组织H.pylori呈阳性表达,19例患者癌组织H.pylori呈阴性表达,阳性感染组miR-32表达量明显高于阴性组(P<0.05)。miR-32高表达组患者H.pylori感染阳性率、TNM分期Ⅲ/Ⅳ期患者比例明显高于低表达组患者(P<0.05)。不同H.pylori干扰量(20:1,100:1)分别与SGC-7901细胞和GES-1细胞共培养48h后,SGC-7901细胞miR-32表达量均高于GES-1细胞(P<0.05),且具有H.pylori干扰量依赖性。si-miR-32组细胞的增殖率明显低于si-NC组(P<0.05);si-miR-32组细胞与H.pylori共培养后细胞增殖率明显低于si-NC组细胞与H.pylori共培养(P<0.05)。同时si-miR-32组细胞与H.pylori共培养后细胞增殖率也高于单独培养的si-miR-32组细胞。结论miR-32在H.pylori相关胃癌中呈异常高表达,并且与H.pylori感染诱发癌变有关。

Objective To study the impact of Helicobacter pylori(H.pylori) infection on miR-32 expression and proliferation of gastric cancer cells SGC-7901. Methods The H.pylori infection was confirmed by positive results of bacterial culture in 66 patients in our hospital from July 2017 to April 2018. The expressions of miR-32 and Cag A mRNA were detected by qRT-PCR;and the relationship of miR-32 and clinical feature was analyzed. The expressions of miR-32 in SGC-7901 cells and GES-1 cells co-cultured with H.pylori respectively were detected by qRT-PCR. The proliferation of SGC-7901 cells transfeced with miR-32 inhibitor with or without H.pylori co-culture were determined by MTT. Results There were 47 patients with positive H.pylori expression and 19 patients with negative H.pylori expression. The expression level of miR-32 was higher in H.pylori positive patients than in negative H.pylori patients(P<0.05), related positively to TNM stage and H.pylori infection(P<0.05). The expression levels of miR-32 were higher in SGC-7901 co-cultured with H.pylori(20:1, 100:1) than in GES-1 cells with H.pylori(P<0.05). The proliferation rates of miR-32 were lower in inhibitor transfection SGC-7901 cells than in si-NC group(P<0.05). The proliferation rates of si-miR-32 transfection were lower in SGC-7901 cells co-cultured with H.pylori than in si-NC co-cultured with H.pylori group(P<0.05). Meanwhile, the proliferation rate of si-miR-32 was still higher in transfection SGC-7901 cells co-cultured with H.pylori than in si-miR-32 transfection SGC-7901 cells without H.pylori co-culture(P<0.05). Conclusions The abnormal expression of miR-32 in H.pylori-associated gastric cancer indicates that it would be involved in pathogenesis of gastric cancer.