N-Acetyltransferase 2 (NAT2) gene polymorphism and exposure to smoking in lung cancer of Chinese males.

N-Acetyltransferase 2 (NAT2) is a polymorphic gene encoding the enzyme that metabolizes arylamine and hydrazine moieties. The NAT2 rs1799930 (G590A) may change drug-induced toxicity and affect cancer susceptibility. To investigate the association between NAT2 rs1799930 polymorphism and susceptibility to lung cancer, we performed a hospital-based case-control study, including 259 lung squamous carcinoma patients and 375 cancer-free hospital controls who were matched by age. A total of 10 ml of venous blood from each patient was collected for the genotype testing. NAT2 rs1799930 polymorphism was analyzed by TaqMan allelic discrimination. Our results showed the evidence by the stratified analysis that smokers with dominant genetic model and A allele in NAT2 rs1799930 decreased risk of lung squamous carcinoma with adjusted OR of 0.64 (95 % CI 0.42-0.96, P = 0.032) and 0.74 (95 % CI 0.54-1.00, P = 0.049), respectively. The significantly increased risk of lung squamous carcinoma was observed in those whose pack-years ≥30 or smoking-index ≥400 with adjusted OR of 3.62 (95 % CI 2.49-5.26, P < 0.001) and 4.29 (95 % CI 2.90-6.36, P < 0.001), respectively. In conclusion, NAT2 rs1799930 polymorphism is an important factor of lung squamous carcinoma resistance in Chinese smoking males. People who smoked heavily had a significantly increased risk of lung cancer.