代谢酶基因多态性与肺癌易感性关系的研究

Relationship between genetic polymorphism of metabolizing enzymes and lung cancer susceptibility

目的 探讨代谢活化酶细胞色素P45 0 1A1(CYP1A1)、2D6(CYP2D6)、2E1(CYP2E1)和代谢解毒酶谷胱甘肽硫转移酶 (GSTM 1)基因多态性与肺癌易感性的关系及重度吸烟对肺癌易感性的影响。方法 采用PCR、PCR RFLP等技术检测 180例原发性肺癌患者及 2 2 4例肺部良性疾病患者和正常人 (对照组 )外周血代谢酶基因型。结果 CYP1A1突变等位基因 (m )、CYP2D6野生型等位基因 (w )、CYP2E1A基因型和GSTM 1功能缺失型 ( -)可使患肺癌的危险性增加到 1.5 0～ 1.5 8倍 (P <0 .0 5 )。携带GSTM 1( -)者若同时携带CYP1A1、2D6或 2E1中任意 1个易感基因型 ,可使患肺癌的危险性升高到 2 .2 4～ 2 .69倍 (P <0 .0 5 )。携带相同基因型者 ,重度吸烟比不吸烟者患肺癌的危险性显著升高。重度吸烟人群中携带 4种易感基因型者患肺癌的危险性显著增高 ,达 9.85倍 ( 95 %CI =2 .3 0～ 45 .71)。结论 代谢酶基因的易感等位基因携带者患肺癌的危险性上升 ,且与烟草致癌物暴露剂量呈正相关。

Objective To investigate the relations between metabolizing enzymes’ genetic polymorphism and lung cancer risk in Chinese, especially in heavy smokers. Methods CYP1A1, 2D6, 2E1 and GSTM1 genotypes were detected in 180 patients with lung cancer and 224 controls by PCR-based genotype assays. Results CYP1A1 variant allele, CYP2D6 wild allele, CYP2E1 A genotype, GSTM1-null genotype were found to be associated with lung cancer. The individuals who carried GSTM1-null genotype and one of the CYP1A1, CYP2D6, CYP2E1 ‘in risk’ genotypes had a 2.24--2.69 fold increased risk of lung cancer. The heavy smokers had a significantly increased risk of lung cancer than the non-smokers who carried the same genotype of metabolizing enzymes. The heavy smoker who carried all the four ‘in risk’ genotypes of metabolizing enzymes had an obviously increased risk of lung cancer (OR=9.85, 95%CI=2.30--45.71). Conclusion The individuals who carry the ‘in risk’ genotype of metabolizing enzymes have an increased risk of lung cancer. It is positively associated with tobacco carcinogen dose.