微RNA-449a在胃癌中的表达及其功能研究

目的探讨微RNA（miRNA）－449a在胃癌中的表达及其功能。方法采用逆转录荧光定量聚合酶链式反应PCR）检测miRNA-449a在胃癌组织和配对的正常组织中的表达，分析miRNA-449a与临床病理参数之间的关系。并将miRNA-449a模拟物转染胃癌细胞后进行细胞增殖分析。结果74．63％的癌组织中miRNA-449a表达下降．miRNA-449a在胃癌组织中的表达明显低于配对正常组织，差异有统计学意义（t=2．04，P〈0．05）。miRNA-449a表达在胃癌的肿瘤大小和胃癌临床分期（TNM）各组间均存在明显差异，差异有统计学意义（X2分别=9．69、9．41，P均〈0．05），而miRNA-449a表达在不同性别和年龄之间的差异均无统计学意义（X2分别=0．04、0．01，P均〉0．05）。与阴性对照比较．miRNA-449a模拟物明显抑制胃癌细胞的增殖，差异有统计学意义（t=2t．67，P〈0．05）。结论miRNA—449a在胃癌组织中呈低表达，抑制胃癌细胞增殖，可能发挥抑癌基因的作用。

Expression and function of miRNA-449a in gastric cancer

Objective To investigate the expression and function of miRNA-449a in gastric cancer. Methods The expression of miRNA-449a in gastric cancer tissues and matched normal tissues were detected by real time PCR. And the relationship between clinical characteristics and the level of miRNA-449a was analysed. CCK8 assay was applied to analyze the proliferation after transfecting mimics of miRNA-449a into gastric cancer cells. Results 74.63% miRNA-449a expression in gastric cancer tissues was reduced. Compared with the matched normal tissues, miRNA-449a expression was significantly lower in gastric cancer tissues（t=2.04,P〈0.05）. There were significant differences of miRNA-449a expression in different tumor volume and different TNM stage （X2=9.69,9.41 ,P〈0.05）. But it had no significant correlation between miRNA-449a and sex, age （X2=0.04,0.01,P〉0.05）. Compared with negative control, miRNA-449a mimics could repress proliferation of gastric cancer cells （t=21.67,P〈0.05）. Conclusions miRNA-449a was down-regulated expression in gastric cancer and repressed cell proliferation, which maybe play a role as a tumor suppressor gene.