NAT2 and CYP1A2 Polymorphisms and Lung Cancer Risk in Relation to Smoking Status

We investigated the associations between lung cancer and the gene polymorphisms of the drug metabolizingenzymes, containing cytochrome P450 1A1 (CYP1A1), cytochrome P450 1A2 (CYP1A2), glutathione S-transferaseclass mu (GSTM1), and N-acetyltransferase 2 (NAT2). The study involved 113 lung cancer patients and 121 noncancercontrols divided into never, light and heavy smokers according to pack-years of smoking in Japanese byusing PCR-RFLP. For light smokers, the lung cancer risk of NAT2 intermediate-slow was significantly increased[the adjusted odds ratio (OR): 10.9, 95% confidence intervals (95%CI): 1.75-67.5, P-value: 0.010]. Moreover,never smokers having joint genotypes of NAT2 intermediate-slow and CYP1A2*1F A/A was also associated withincreased the lung cancer risk (OR: 4.95, 95% CI: 1.19-20.6, P-value: 0.028). We suggested that light smokerswith intermediate-slow NAT2 activity were at highest risk for lung cancer and the gene-gene interaction based onintermediate-slow NAT2 activity and high CYP1A2 activity would be increased a lung cancer risk among neversmokers.