结直肠癌中PAQR3甲基化水平及mRNA表达的研究

The methylation and m RNA expression of PAQR3 in colorectal cancer

目的研究结直肠癌组织中抑癌基因PAQR3 mRNA表达情况及甲基化水平,探讨PAQR3基因异常甲基化与结直肠癌的关系。方法收集结直肠癌及正常组织标本54组,用逆转录-聚合酶链反应(RT-PCR)检测结直肠癌标本中PAQR3 mRNA表达水平;用甲基化特异性聚合酶链反应(MSP)法检测结直肠癌标本中PAQR3基因甲基化水平,用以分析PAQR3甲基化水平与临床病理资料的关系。结果 54组结直肠癌标本中PAQR3 mRNA表达降低发生率为57.4%(31/54),正常组织PAQR3 mRNA表达降低发生率为18.5%(10/54),表达差异有统计学意义(P=0.000);癌组织PAQR3基因启动子甲基化发生率为33.3%(18/54),正常组织PAQR3基因启动子甲基化率为5.6%(3/54),二者差异有统计学意义(P=0.000);PAQR3基因甲基化与年龄、分化程度、浸润深度、临床分期、淋巴结转移有关,与性别、部位无关。结论结直肠癌组织中PAQR3表达降低,与其基因启动子发生高甲基化有关。

Objective To investigate the relationship between the methylation level of PAQR3 and colorectal cancer, the methylation level and mRNA expression of PAQR3 gene in colorectal cancer were detected. Methods 54 colorectal cancers and 54 colorectal normal tissues were collected to detect the expression of mRNA level by reverse transcriptase PCR（RT-PCR）, the methylation level of PAQR3 gene were detected by Methylation Specific PCR（MSP）, which were used to analyze the relationship between methylation of PAQR3 and clinical data. Results Expression of PAQR3 mRNA in 54 normal tissues were significantly higher than that in 54 colorectal cancer tissues, the expression rates were 18.5%（10/54） and 57.4%（31/54）, there was significant difference between cancer and normal tissues（P= 0.000）.The PAQR3 gene promoter methylation rate of colorectal cancer and colorectal normal tissues were 33.3%（18/54）and 5.6 %（3/54）, there was significant difference between cancer and normal tissues（P= 0.000）.There was significant difference in age, differentiation, infiltration, clinical stage and the metastasis of lymph node in colorectal cancer, but not in sex and location. Conclusion PAQR3 expression can be reduced in colorectal cancer, PAQR3 gene promoter hypermethylation may play an important role in oncogenesis of colorectal cancer.