P53 AND RAS GENE-MUTATIONS IN LUNG-CANCER - IMPLICATIONS FOR SMOKING AND OCCUPATIONAL EXPOSURES

This paper reviews mutational activation of ras oncogenes and inactiva tion of the p53 tumor suppressor gene in human lung cancer. We discuss the frequency, type, and location of mutations in these genes in rela tion to Known etiological factors for lung cancer. The most studied ex amples of these are exposure to tobacco smoke, and to radon and asbest os fibers at work. We summarize data from our laboratory on K-ras and p53 mutations in fresh tissue samples from patients with resected prim ary lung carcinoma whose smoking and occupational histories were Known . Most of the tumors examined were histologically non-small cell carci noma (NSCLC), mainly of the squamous cell carcinoma and adenocarcinoma types. We compare the prevalence and nature of mutations in the two h istological types of NSCLC.