中文摘要：

目的探讨RNA甲基化相关蛋白Mettl-14在胃癌样本及癌旁组织中的表达差异,并分析其对胃癌细胞系功能的调节作用。方法用实时定量PCR方法检测83例分化程度不同胃癌及对应癌旁组织中Mettl-14 mRNA水平的表达;使用RNA干扰方法敲低Mettl-14在胃癌细胞系MGC-803中的表达,通过细胞增殖实验、细胞周期实验、划痕实验和Transwell实验检测Mettl-14敲低后对MGC-803细胞功能的影响。结果与癌旁组织相比Mettl-14 mRNA的表达水平在胃癌组织显著降低;且Mettl-14 mRNA的低表达与肿瘤分级相关（P〈0.05）;在MGC-803细胞系中敲低Mettl-14,可促进细胞增殖、细胞周期运行、细胞迁移和侵袭。结论 Mettl-14可能在胃癌发生发展中发挥抑癌基因作用,并有可能成为胃癌诊断标志物及治疗靶点。

英文摘要：

Objective To investigate the expression of Mettl-14 mRNA in gastric cancer tissues and the functional significance of Mettl-14 in MGC-803 cell line. Methods Real-time PCR analysis was performed to detect the expression of Mettl-14 mRNA in 83 pairs of clinical gastric cancer tissues and control tissues. RNA interference was used to knock-down the endogenous Mettl-14 level in MGC-803 cells. The effect of Mettl-14 knock-down on cell proliferation,cell cycle,cell migration and invasion was detected by CCK-8,FACS,wounding heal and Transwell assays,respectively. Results The expression of Mettl-14 mRNA was down-regulated in gastric cancer as compared to the normal tissues,and this down-regulation was correlated with tumor grading. Furthermore,knock-down of endogenous Mettl-14 could promote cell proliferation,cell cycle progression,cell migration and invasion. Conclusions Mettl-14 might act as a tumor suppressor in gastric carcinogenesis,and it may sever as a novel biomarker as well as chemotherapy target for gastric cancer.