miR-204在胃癌生长中的作用及机制

目的:探讨microRNA-204(miR-204)在胃癌中的表达,研究miR-204在胃癌细胞增殖中的作用和机制。方法:采用RT-PCR方法检测胃癌组织、胃癌细胞中的miR-204相对表达量；分析miR-204的表达与临床病理参数的关系；瞬时转染上调胃癌SGC7901细胞中miR-204的表达量，CCK8检测转染前后细胞增殖能力的变化；Western blot检测转染前后SGC7901细胞中Bcl-2表达的变化。结果:胃癌组织中miR-204相对表达量（1.94±0.78）明显低于正常胃组织（4.01±1.47）（P＜0.01）；同样，人胃癌细胞株中miR-204表达水平明显低于正常胃上皮细胞（P＜0.01）。胃癌组织中miR-204的表达水平与肿瘤的大小、远处转移和TNM分期明显相关（P＜0.05）。CCK8结果显示，miR-204 mimics转染后SCG7901细胞的增殖率较转染前明显下降（P＜0.05），Western blot结果显示胃癌细胞中Bcl-2的表达水平较转染前明显下调（P＜0.05）。结论:miR-204在胃癌组织中低表达且与其恶性生物学行为相关，上调miR-204可通过下调Bcl-2的表达抑制胃癌细胞的增殖。

The effect and mechanism of miR -204 on proliferation of gastric cancer

Objective:To investigate the expression of miR-204 in patients with gastric cancer and to analyze the effect and mechanism of miR-204 on proliferation of gastric cancer.Methods:Gastric cancer tissues and gastric cancer cells were detected by RT-PCR.The relationships between the level of miR-204 in cancer tissues and the pathological characteristics were analyzed.miR-204 mimics was transiently transferred into SCG7901cells in vitro.Cell viability was analyzed by CCK8 assay．Expression of Bcl-2 protein was detected by Western blot.Results:The expression level of miR-204 was down-regulated in gastric cancer tissues as compared with the paired normal gastric tissues (P＜0.05).The similar pattern was seen in gastric cancer cells.The expression of miR-204 in tumor tissues was associated with tumor size,lymphatic metastasis and TNM stages (P＜0.05).CCK8 showed that over-expression of miR-204 inhibited the proliferation of SGC7901 cells.Western blot indicated that over-expression of miR-204 led to a significant decrease in the Bcl-2 protein levels in SGC7901 cells.Conclusion:Low expression of miR-204 in gastric cancer have relation with malignant biological behavior.Up-regulation of miR-204 might inhibit the proliferation of gastric cancer cells by down-regulation of Bcl-2.