SM22α基因启动子区低甲基化与胃癌发生发展的相关性研究

Correlation between hypomethylation of SM22αgene promoter region and the pathogenesis and development of gastric cancer

目的探讨平滑肌蛋白22α(SM22α)基因启动子区甲基化状态及mRNA表达在胃癌发生中的作用,为胃癌早期诊断和治疗寻找新的靶点。方法甲基化特异性聚合酶链反应检测56例胃癌及其对应的正常癌旁组织中SM22α基因启动子区甲基化状态;荧光实时定量PCR技术检测胃癌组织及正常癌旁组织中SM22α基因mRNA的表达。比较胃癌组织和正常癌旁组织中SM22α基因启动子区甲基化状态及mRNA表达的差异情况,并分析它们与胃癌患者临床病理特征之间的关系。结果胃癌组织中SM22α基因启动子区甲基化率显著低于正常癌旁组织(P<0.05),其mRNA表达水平显著高于正常癌旁组织(P<0.05),且甲基化阳性的胃癌组织中SM22α基因mRNA表达量显著低于甲基化阴性的胃癌组织(P<0.05)。胃癌组织中SM22α基因启动子区甲基化状态及、mRNA表达水平与胃癌患者的淋巴结转移呈显著相关(P<0.05)。结论SM22α基因启动子区的低甲基化导致其表达升高可能在胃癌发生、发展中起重要作用,SM22α有可能成为胃癌分子诊断和治疗的重要靶点。

Objective To investigate the expression and methylation status and SM22αmRNA in the pathogenesis of gastric cancer,and to find an new target for early detection and treatment of gastric cancer.Methods The methylation status of SM22αgene promoter was detected in 56 cases of gastric cancer and corresponding adjacent normal tissues by using methylation-specific polymerase chain reaction.The expression levels of SM22αmRNA were detected by using RT-qPCR.The methylation status and expression levels of SM22αwere observed and compared between the two groups to analyzed their correlation with the clinicopathological characteristics of gastric cancer.Results The methylation rate of SM22αgene promoter region in gastric cancer tissues was significantly lower than that in adjacent normal tissues(P<0.05),and the expression levels of SM22αmRNA in gastric cancer tissues were significantly higher than those in adjacent normal tissues(P<0.05).Moreover,the expression levels of SM22αmRNA in gastric cancer tissues with positive methylation were significantly higher than those with negative methylation(P<0.05).In addition,there was a significant correlation between the methylation status as well as expression levels of SM22αand lymph node metastasis of patients(P<0.05).Conclusion The increase of SM22αmRNA levels due to hypomethylation in its promoter region may be involved in the pathogenesis and development of gastric cancer,which may be regarded as an important target in early detection and treatment of gastric cancer.