肺癌组织中经典Wnt信号途径相关基因异常甲基化的检测

Abnormal methylation of the canonical Wnt signaling pathway-related genes in lung tissues

目的检测肺癌组织中经典Wnt信号途径相关基因(WIF-1、sFRP-1、DKK-3)启动子的甲基化状态及其与患者临床病理特征间的关系,探讨其在肺癌发生中的作用。方法应用巢式甲基化特异性聚合酶链反应(nMSP),检测30例纤维支气管镜活检肺癌组织、11例石蜡包埋肺癌组织和10例肺良性疾病患者的纤支镜活检标本以及肺腺癌A549细胞株中WIF-1、sFRP-1和DKK-3基因启动子区域的甲基化。结果肺良性疾病患者活检标本未检测到所选基因的甲基化,肺癌患者活检标本WIF-1、sFRP-1、DKK-3基因启动子甲基化的发生率分别为:46.3%、29.3%和36.6%;重度吸烟患者肺癌组织3个基因的甲基化发生率明显增高(P<0.05)。肺腺癌A549细胞株中WIF-1和DKK-3基因呈甲基化状态,而sFRP-1基因呈未甲基化状态。结论经典Wnt信号途径相关基因启动子甲基化可能与吸烟引起的肺癌有关,甲基化的WIF-1、sFRP-1和DKK-3基因可能成为肺癌表观遗传干预治疗的新靶点。

[Objective] To detect the methylation status of canonical Wnt signaling pathway-related genes （WIF-1, sFRP-1, DKK-3） and its relationship with the clinicopathology feature in biopsy samples of fiberoptic bron-choscopy （FB） in patients with lung carcinoma, and explore its role in the carcinogenesis of lung carcinoma. [Methods] Nested methylation-specific polymerase chain reaction （nMSP） was used to examine the CpG-island methylation status of WIF=1. sFRP-1- and DKK-3 genes for biopsy samples of FB in 30 patients with lung carcino- ma, 10 patients with benign pulmonary disease, and 11 paraffin imbedded tissues as well as lung adenocarcinoma cell line A549. [Results] Methylation of the above genes was not detected in any biopsy samples of benign pulmonary disease, but was found in tumor tissues by 46.3% （WIF-1）, 29.3% （sFRP-1）and 36.6%（DKK-3）. Heavy-smoking patients with lung carcinoma had even higher methylation rate in tumor tissues （P 〈0.05）. WIF-1 and DKK-3 gene were methylated in lung adenocarcinoma cell line A549, but sFRP-1 was not. [Conclusions] Methy-lation of the canonical Wnt signaling pathway related genes may contribute towards the pathogenesis of lung carcinoma caused by smoking, and the methylated WIF-1, sFRP-1 and DKK-3 may be an important new therapeutic targets for the epigenetic therapy intervention of lung carcinoma.