Association of glutathione S-transferase M1 polymorphisms and lung cancer risk in a Chinese population

Background: Genetic polymorphisms of glutathione S-transferase M1 (GSTM1) are thought to have significant effects on the metabolism of environmental carcinogens and thus on lung cancer risk, but the reported results are not always consistent. The aim of this study is to investigate the relationship between GSTM1 genetic polymorphism and lung cancer risk in a Chinese population.

Methods: A population-based control study was conducted in 360 lung cancer patients and 360 cancer-free controls. The genotype of the GSTM1 gene was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.

Results: We observed a stronger association between GSTM1 null genotype and lung cancer [odds ratio (OR)=1.59, 95% confidence interval (CI)=1.17, 2.17; P=0.003]. This association was also found in squamous cell carcinoma (OR=1.73, 95% CI=1.16, 2.59; P=0.008). In the analysis combining GSTM1 polymorphism and smoking, smokers with the null genotype who had smoked for ≥ 30 pack-years had higher risk (OR=10.06, 95% CI=5.16, 19.61; P<0.001) compared with non-smokers with the wild-type genotype.

Conclusions: This study suggested that GSTM1 polymorphism plays a role in the development of lung cancer and modifies the risk for smoking-related lung cancer in a Chinese population.