【摘要】 目的观察大肠癌组织中甲硫腺苷磷酸化酶(MTAP)mRNA的表达,探讨MTAP mRNA与其启动子去甲基化的相关性。方法采用半定量逆转录PCR法检测76例正常大肠黏膜和大肠癌组织中的MTAP mRNA,采用MSP法检测大肠癌组织中MTAP基因甲基化状态。结果大肠癌组织中MTAP mRNA表达阳性率为90.78%(69/76),高于正常组织中的5.26%(4/76),P<0.05;MTAP mRNA表达与大肠癌患者的年龄、性别及病变部位、肿瘤大小无关(P均>0.05),而与肿瘤的分化程度、临床分期及淋巴结转移有关(P均<0.05)。正常大肠组织中MTAP基因启动子甲基化频率为95.00%(19/20),高于大肠癌组织中的39.47%(30/76),P<0.01;MTAP基因甲基化大肠癌组织中MTAP mRNA表达率显著低于去甲基化大肠癌组织(χ2=8.592,P<0.05),大肠癌组织中MTAP mRNA表达与其启动子去甲基化呈正相关(r=0.919,P<0.05)。结论大肠癌组织中MTAP mRNA高表达与其启动子去甲基化有关。更多还原

【Abstract】 Objective To detect the mRNA expression of 5′-methylthioadenonine phosphorylase gene(MTAP) and MTAP gene promoter methylation degree in colorectal cancer,and discuss the correlation between them.Methods We used semi-quantitative reverse-transcription polymerase chain reaction(SqRT-PCR) to detect the mRNA expression of MTAP in the colorectal cancer and normal tissue,and the methylation status of MTAP gene promoter was examined by methylation-specific polymerase chain reaction(MSP) method.Results Positive rate of MTAP mRNA expression in the colorectal cancer was significantly higher than that in the normal mucosa.The positive expression of MTAP mRNA had no correlation with the patient′s age,sex,site and the size of colorectal carcinoma.The positive expression of MTAP mRNA had close correlation with the clinical stages,differentiation and lymph node metastasis of the cancer.The methylation frequency of MTAP promoter was significantly lower in colorectal cancer than that in normal tissue.The genetic expression rate of MTAP in the colorectal cancer tissue with methylation positive of MTAP was significantly lower than that in the colorectal cancer with methylation negaitive(χ2=8.592,P<0.05).And it presented positive correlation between the genetic expression of MTAP in the colorectal cancer and the demethylation status of MTAP promoter(r=0.763,P<0.05).Conclusion Promoter′s demethylation can lead to gene MTAP high expression in colorectal cancer.更多还原