非小细胞肺癌组织DAPK基因甲基化状态分析

Analysis of Methylation Status of DAPK Genes in Non-small Cell Lun~ Cancer Tissues

目的研究非小细胞肺癌组织的甲基化状态。应用于肺癌的早期检测。方法研究者于2011年9月～2012年1月随机采集96例行外科切除术并经病理确诊的非小细胞肺癌（NSCLC）患者的肺癌组织和癌旁组织样本，用甲基化特异性PCR（MSP）技术检测样本的死亡相关蛋白激酶（DAPK）基因甲基化状态，并按肺癌的临床分期、分类和病理分型对癌组织进行分组，最后用卡方检验分析癌组织和癌旁组织DAPK基因甲基化检出率的统计学差异，以及不同分组方法下癌组织的组间差异。结果肺癌组织DAPK基因甲基化率为51％．癌旁组织甲基化率为12．5％，二者差异有统计学意义（X2=32．893，P〈0．05）；肺癌0～Ⅰ期与Ⅱ～Ⅳ期相比，癌组织DAPK基因甲基化检出率差异无统计学意义（X2=0．017，P〉0．05）；中央型肺癌与周围型肺癌相比，癌组织DAPK基因甲基化检出率差异无统计学意义（X2=3．603，P〉0．05）；鳞癌与腺癌及其它相比．肺癌组织DAPK基因甲基化检出率差异无统计学意义（X2=0．157，P〉0．05）。结论肺癌组织的DAPK基因甲基化水平与癌旁组织比较有显著性差异，且癌组织的甲基化状态与肺癌的临床分期、临床分类和病理分型无明显相关性，提示有关样本的DAPK基因甲基化，可能成为肺癌临床诊断的一个指标。

Objective To analyze the methylation status of DAPK genes in non-small cell lung cancer（NSCLC） tissues,and to apply the results in the early diagnosis of lung cancer. Methods The researchers collected randomly the samples of lung cancer tissues and adjacent normal tissues from 96 NSCLC patients during Sep. 2011 to Jan. 2012,who had undergone opera- tions and had been confirmed by pathology. The methylation states of DAPK genes in samples were tested with methylation- specifc PCR（MSP）, and the cancer tissues were grouped according to the clinical staging, clinical classification and pathology type of NSCLC. Chisquaretest was used to analyze the statistical difference in methylation between tumor tissues and adja- cent normal tissues,and that between groups of tumor tissues classifed by different methods. Results The total frequency of DAPK methylation in lung cancer tissues was 51%, while the frequency in the adjacent nomal tissues was t2.5~, thus there＇s statistical significance in the difference between them （X2 = 32. 893, P%0.05）. But the difference of the methylation status of lung cancer tissues between stage 0～ Ⅰ and stage Ⅱ ～ Ⅳ（2;2 =0. 017, P〉0.05） was not significant,nor was cen- tral type and peripheral type （X2 = 3. 603, P〉0.05）, nor was squamous carcinoma and adenomatous carcinoma with other types （X2=0. 157,P〉0.05）. Conclusion The result that the frequency of DAPK methylation was siglificantly higher in lung cancer tissues than that in the adjacent nomal tissues,and there was no obvious assoiation between lung cancer tissues＇ methylation status and the clinical staging,clinical classification and pathology type of NSCLC indicates that the detection of methylation of DAPK genes in samples associated may be used as an effective index to diagnose lung cancer.