Genetic polymorphisms of NAD(P)H quinone oxidoreductase, CYP1A1 and microsomal epoxide hydrolase and lung cancer risk in Nanjing, China

Genetic variations in metabolic activation or detoxification enzymes have b een thought to contribute to individual differences in lung cancer suscepti bility. Genetic polymorphisms of NAD(P)H quinone oxidoreductase (NQOI), cyt ochrome P4501A1 (CYP1A1) and microsomal epoxide hydrolase (HYL1) have been associated with increased lung cancer risk in Asian populations. In the pre sent study, the possibility of an association of NQO1, CYP1A1 and HYL1 gene tic polymorphisms with lung cancer was examined among residents in Nanjing, China. A total of 84 lung cancer patients and 84 control subjects were mat ched by age, gender, occupation and smoking status. No significant associat ion was observed for these genetic polymorphisms with the overall incidence of lung cancer. When the groups were stratified according to smoking statu s, we found that smokers carrying the HYL1*2 allele had a higher relative r isk for lung cancer Odds ratio ((OR), 5.66; 95% confidence interval (95% CI ), 1.71-18.68). The association was also found with squamous cell carcinoma (OR, 3.23; 95% CI, 1.00-10.38). Our results suggest that HYL1*2 polymorphi sm might be a risk factor for smoking-associated lung cancer in China. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.