ABSTRACT
Lung cancer is considered as one of the most frequent cancers worldwide, and has been the cause of more than one million mortalities each year. Exposure to tobacco smoke is the primary cause of most lung cancers, since it contains several thousand compounds, including more than 50 known carcinogens. However, a small fraction of individuals who are exposed to tobacco smoke develop lung cancer, therefore genetic factors may render some tobacco smokers more susceptible to cancer. Genetic polymorphism in genes that encode metabolizing enzymes may be related to differentiated susceptibility of malignancy. CYP1B1 protein is a member of the more significant CYP1 subfamily enzymes, involved in environmental carcinogen metabolic activation. The most studied polymorphism in CYP1B1 gene includes 4325 C-G, resulting in an amino acid change from leucine to valine amino acid. A case-control study [included 65 lung cancer cases and 80 healthy controls] was designed based on the RFLP-PCR method to estimate the possible association of this polymorphism with lung cancer susceptibility in the Iranian population. Regarding the distribution of CYP1B1 L432V genotypes, there were no meaningful differences among controls and lung cancer patients, however among patients carrying the CC genotype, tobacco smokers had a considerable elevated risk for lung cancer compared to those who had the GG genotype. CYP1B1 L432V polymorphism has an important role in lung cancer risk. Therefore, further studies are recommended for investigation of other related CYP1B1 gene polymorphisms, their association with affective genes and regulatory factors in the Iranian population.