ASSOCIATION OF CYTOCHROME P450 GENE POLYMORPHISM WITH LUNG CARCINOMA AMONG ADULT MALE SMOKER
Background & Objective Lung Cancer is a major health problem worldwide with high fatality rate. Smoking is a known to be the most important risk factor, though all smokers do not develop lung cancer. This is because individuals differ in metabolism of pro-carcinogens present in cigarette smoke by cytochrome P450 (CYP 450) enzymes. Variable forms of CYP450 enzymes are produced due to presence of multiple alleles or polymorphs of CYP 450 gene. CYP 1A1 polymorphisms were the first CYP genes to be associated with lung cancer. Several single nucleotide polymorphisms (SNPs) have been identified in CYP1A1 gene, some of which are suspected to be linked with lung cancer. This study has been done to find association of CYP1A1 genes- m1, m2, and m4 polymorphism with lung cancer in heavy smokers. Methods & Results This is an observational analytical study on heavy smoker eighty males, of which forty were with lung cancer (Group I) and remaining forty were with non-lung cancer (Group II). CYP1A1 gene m1, m2 and m4 polymorphism was detected by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) techniques. Steps involved in these techniques are DNA isolation, polymerase chain reaction, DNA electrophoresis and restriction fragment length polymorphism. CYP1A1 m1 Gene polymorphism was found in 3 out of 22 (13.6%) cases of squamous cell lung cancer and only 1 case (4.5%) had both the m1 and m2 gene polymorphisms. None of these polymorphisms was seen in non-lung cancer smokers and in patients with non-squamous cell lung cancer. Interpretation & Conclusion CYP1A1 gene related m1 and m2 polymorphisms may have some contributory role for lung squamous cell carcinoma development and m4 polymorphism has no role in development of lung cancer in Indian population of eastern part of Gujarat. All lung carcinoma cases may not have gene polymorphism of CYP1A1...