MGMT基因启动子甲基化与乳头状甲状腺癌预后的关系

Correlation of MGMT gene promoter methylation with prognosis of papillary thyroid cancer

目的检测乳头状甲状腺癌(PTC)组织和良性甲状腺肿瘤组织中MGMT基因启动子区甲基化状态,分析MGMT基因甲基化与PTC预后的关联,旨在为探索PTC预后提供依据。方法采用甲基化特异PCR法检测60例PTC及60例良性甲状腺肿瘤组织的MGMT基因启动子区甲基化状态,比较两组的不同病理参数间MGMT基因甲基化状态,并分析其与PTC预后的关系。结果病例组MGMT甲基化阳性率(51.7%)明显高于对照组(26.7%);病例组MGMT甲基化阳性率在有/无吸烟、有/无饮酒间差异显著(P<0.05);年龄越大、肿瘤直径越大、有淋巴结转移、临床分期越高、有MGMT基因甲基化是PTC较差预后的独立影响因素(P<0.05)。结论 MGMT基因启动子区甲基化是PTC重要的早期事件,良性甲状腺肿瘤组织中虽然也可发生,但频率远低于PTC;MGMT基因启动子区甲基化对预后具有提示作用。

Objective To explore the status of MGMT promoter methylationof papillary thyroid cancer （PTC） and benign papillary thyroid carcinoma and to determine whether MGMT methylation is associated with the prognosis of PTC.Methods Methylation-specific PCR was used to detect the MGMT methylation status in 60 pairs of PTC-control in our hospital from Jan.2007 to Apr.2008,the differences of methylation status was compared.The Kaplan-Meier,Log-rank tests were used to analyze the correlation between MGMT promoter methylation and prognosis of PTC.Results MGMT methylation rate （51.67％） of the cases was significantly higher than that of the control （26.67％） （x2 =7.869,P =0.06） ; Smoking and alcohol consumption affected the MGMT methylation rate （P ＜ 0.05） ; lymph node metastasis,TNM stage,tumor diameter increased MGMT methylation rate significantly （P ＜ 0.05） ; Elderly patients with a larger tumor,lymph node metastasis,and advanced clinical stage had MGMT methylation,whose prognosis usually was poorer （P ＜ 0.05）.Conclusions MGMT promoter methylation is an important early event in PTC ; although benign thyroid tumor may also present MGMT promoter methylation,but the frequency is much lower; MGMT promoter methylation in PTC patients usually suggests a poor prognosis.