Polymorphisms of DNA repair genes and lung cancer in chromium exposure.

Chromium is a well known carcinogen involved in the lung cancer development. Polymorphism of some of the DNA repair genes may be associated with elevated risk of cancerous transformation. In the present study, we investigated the polymorphisms of the following selected members of the base and nucleotide excision repair genes: XPC (Lys939Gln), XPD (Lys751Gln), XRCC1(Arg399Gln), and hOGG1(Ser326Ser), and the risk they present toward the development of lung cancer, with emphasis on the effect of chromium exposure. We analyzed 119 individuals; 50 patients exposed to chromium with diagnosed lung cancer and 69 healthy controls. Genotypes were determined by a PCR-RFLP method. We found a significantly increased risk of lung cancer development in XPD genotype Lys/Gln (OR=1.94; 95% CI=1.10-3.43; p=0.015) and in the gene combinations: XPD Lys/Gln+XPC Lys/Gln (OR=6.5; 95% CI=1.53-27.49; p=0.009) and XPD Lys/Gln+XPC Gln/Gln(OR=5.2; 95% CI=1.07-25.32; p=0.04). In conclusion, gene polymorphisms in the DNA repair genes may underscore the risk of lung cancer development in the chromium-exposed individuals.