A caseª²control study on relationship between absence of GSTM1 gene, smoking and susceptibility to nonª²small cell lung cancer

    QIAO Guiª²Bin1, SUN Changª²Sheng2, LI Liangª²Shou2, ZENG Weiª²Sheng1, JIANG Renª²Chao1

    1Department of Thoracic Surgery, General Hospital, Guangzhou Military Command, 510010, China, 2Department of Epidemiology, School of Preventive Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To evaluate the role of absence of glutathione Sª²transferase M1 gene (GSTM1) in the susceptibility to smokingª²related lung cancer. METHODS: A caseª²control study was designed and the absence of GSTM1 gene was detected with PCR technique in 213 cases and 199 controls. RESULTS: The absence of GSTM1 gene in the lung cancer group (61%) and controls (48%) was significantly different (P=0.007). Overall, the GSTM1 null genotype conferred a 70% increased risk of lung cancer, OR=1.7(95% CI 1.2-2.5, P=0.007). The absence of the GSTM1 gene encoding the glutathione Sª²tansferase M1 enzyme significantly increased the risk to people exposed to the carcinogens in tobacco smoke, OR=1.9(95% CI 1.2-3.0, P=0.011). People with GSTM1 genotype absence exposed to smoking of more than 30 packs¡Áyear had approximately six fold greater risk of cancer than people in the lowest risk group (nonsmokers with GSTM1 genotype present). CONCLUSION: GSTM1 plays an important role in the development of nonª²small cell lung cancer. GSTM1 null genotype is one of the major host factors of susceptibility to lung cancer. ......