Objective: to study the correlation of polymorphisms of CYP1A1 MspI, GSTM1 null genotype, cooking oil fumes independently and in combination with the risk of non-smoking lung cancer in females.
Methods: one hundred and sixty female non-smoking patients with primary lung cancer and 160 controls were enrolled from Xiangya Hospital of Central South University. PCR-RELP and PCR were used to detect the distribution of CYP1A1 MspI and GSTM1 genotypes respectively. The correlation of these genes and cooking oil fumes with the susceptibility to lung cancer was analyzed.
Results: There was a significant difference in the frequencies of cooking oil fumes exposure between cancer cases and controls (χ(2) = 10.734, P < 0.01);but there was no statistical difference in CYP1A1 MspI polymorphisms between the 2 groups (χ(2) = 3.731, P > 0.05). The combination of CYP1A1 polymorphisms and cooking oil fumes significantly increased the risk of lung cancer. The frequencies of GSTM1 null genotype was significantly different between cancer cases and controls (χ(2) = 0.518, P < 0.05). The risk of lung cancer was higher in those with the GSTM1 null genotype and the OR was 1.697 (95%CI 1.090 - 2.640). Individuals with both GSTM1 null genotype and exposure to cooking fumes had a higher risk of cancer than those with only one of them, the OR being 3.617 (95%CI 1.899 - 6.891). The combination of the two genes significantly increased the risk of lung cancer.
Conclusions: cooking oil fumes exposure was a risk factor for non-smoking lung cancer in females. The combination of CYP1A1 with cooking oil fume increased the risk of female lung cancer. GSTM1 null genotype was associated with risk of lung cancer in non-smoking females. The combination of GSTM1 null genotype and cooking oil fumes significantly increased the risk of female lung cancer. The combination of CYP1A1 and GSTM1 significantly increased the risk of lung cancer.