Occupational cancer genetics: Infrequent ras oncogenes point mutations in lung cancer samples from chromate workers

Background Chromium carcinogenicity and mutagenicity are no longer disputed . However although chromium has various genetic effects that induce cancer; its mechanism of inducing lung cancer in humans is still not fully underst ood. p53, a tumor suppressor gene, was found to be infrequently mutated in samples of lung cancer in workers with long occupational exposure to chromi um, suggesting other cancer-related genes to be targeted in such tumors. Methods To assess the contribution of the ras oncogenes in the pathogenesis of chromate-related lung cancel; we studied point mutations at the critica l positions of codons 12, 13, and 61 of the Ha-ras and Ki-ras oncogenes in 38 lung cancer samples derived from Japanese patients who worked in the chr omate industry for long periods. We used both radioactive isotope and non-r adioisotope PCR-SSCP techniques. Results The results of this study demonstrated that activation of ras genes due to point mutations in chromate-related lung cancer is a rare event. Conclusion Ras oncogenes activated by point mutations do not have a major r ole in the process of tumorigenesis of chromate-related lung cancer (C) 200 1 Wiley-Liss, Inc.