CDH1基因甲基化水平与肺癌的相关性研究

目的探讨CDH1（cadherin 1）基因甲基化水平与肺癌及其病理类型之间的相关性．方法应用半定量荧光MSP检测50例肺癌患者的癌、癌旁和远癌肺组织及5例非肺癌对照肺组织标本中的CDH1甲基化的相对比值，并用免疫组化方法对部分结果进行验证．结果肺癌组织、癌旁组织、远癌组织以及非肺癌对照肺组织CDH1甲基化相对比值的中位数分别为0．272、0．227、0．119和0．000．癌组织和癌旁组织（P〈0．05）、癌组织和远癌组织（P〈0．05）、远癌组织和非肺癌对照肺组织（P〈0．05）的CDH1启动子甲基化水平的差异均有统计学意义（P〈0．05）；癌组织、癌旁组织和远癌组织中的鳞癌、腺癌及腺鳞癌CDH1基因甲基化相对比值之间的差异均无统计学意义（P〉0．05）．免疫组化结果与半定量荧光MSP检测结果符合．结论CDH1基因甲基化水平与肺癌具有相关性，与肺癌的组织类型无相关性．CDH1异常甲基化和E—cad表达的减弱和缺失可能是肺癌发生和发展过程中的重要因素．

The Relationship between CDH1 Promoter Methylation and Lung Cancer

Objective To explore the relationship between CDH1 promoter methylation and lung cancer or clinical pathological type. Methods The semiquantitative fluorescence-based real-time MSP method was used to detect the relative rate of CDH1 aberrant methylation in all 50 cases of lung cancer tissues （LCT） , paracancer lung tissues （PCLT） , farcancer lung tissues （FCLT） and 5 cases of non-cancer lung tissues （NCLT）. The two-step immunohistochemical method was used to confirm some results of MSP. Results The medians of the relative rate of CDH1 aberrant methylation in LCT, PCLT, FCLT and NCLT were 0.272 3, 0.226 8, 0.119 1 and 0.000 0. Statistic analysis showed that there were significant differences between lung cancer tissues and paracancer lung tissues or farcancer lung tissues （ P 〈 0.05 ）. There were also significant differenees between farcancer lung tissues and paracancer lung tissues or non-cancer lung tissues （P 〈 0.05）. But there was no difference among squmaous cell carcinoma （SCC） , adenocarcinoma （Ad） and adenosquamous carcinoma （AdCa） in the groups of lung cancer tissues, paracancer lung tissues and farcancer lung tissues. The immunohistochemistry results were as same as the MSP results. Conclusions CDH1 promoter methylation is associated with lung cancer. But there is no evident relationship between CDH1 promoter methylation and pathological types. CDH1 aberrant methylation and E-cadherin protein reduced expression may play important roles in tumorigenesis and development of lung cancer.