甲状腺乳头状癌组织中hMLH1基因启动子甲基化及其临床意义

Aberrant methylation of hMLH1 gene promoter in papillary thyroid cancer and its clinical significance

目的探讨甲状腺乳头状癌（PTC）组织中hMLH1基因启动子甲基化及其临床意义。方法采用甲基化特异性聚合酶链反应法检测152例PTC组织及癌旁正常组织中hMLH1基因启动子甲基化状态，并分析其与临床病理特征的关系。结果152例PTC组织中，hMLH1基因启动子甲基化57例，其中完全甲基化33例，部分甲基化24例，甲基化率为37．5％。152例癌旁正常组织中，hMLH1基因启动子甲基化8例（均为部分甲基化），甲基化率为5．3％。PTC组织中的hMLH1基因启动子甲基化率明显高于癌旁正常组织（P〈0．05）。hMLH1基因启动子甲基化与原发灶大小、原发灶数量、局部侵犯情况、T分期和颈部淋巴结转移情况有关（均P〈0．05），而与患者性别、病理分期无关（均P〉0．05）。结论hMLH1基因启动子甲基化是PTC组织中较常见的分子事件，与PTC的进展关系密切。

Objective To investigate the aberrant promoter methylation of hMLH1 gene promoter and its clinical significance in papillary thyroid cancer （PTC）. Methods methylation of hMLH1 gene promoter in the cancer tissue and matched tumor-adjacent normal tissue of 152 PTC patients were detected by real-time methylation specific PCR （qMSP）. The relationship between the methylation of hMLH1 gene promoter and clinicopathological features was analyzed. Results The methylation rate of hMLH1 gene promoter in cancer tissues was 37.5% （57/152）, of which 33 cases were totally methylated and 24 cases were partially methylated. The methylation rate of adjacent normal tissues was 5.3% （8/152） （all were partially methylated）. The methylation rate of VFC tissues was significantly higher than that in the tumoradjacent normal tissue （ P 〈 0.01 ）. The promoter methylation of hMLH1 gene in PTC was significantly correlated with age, size and number of the primary lesion, local invasion, T stage and lymph node metastasis （ P 〈 0.05）, but not correlated with gender and clinical stage （P 〉 0. 05 ）. Conclusion Promoter methylation of hMLH1 gene is a common molecular event in PTC tissue, and it is significantly correlated with the progression of PTC.