The chromosome region 18q21 has been shown to be frequently deleted in lung cancers. Recent identification at this locus of DPC4, a gene whose inactivation has been suggested to play a role in pancreatic carcinogenesis, prompted us to examine whether it might also be altered in lung cancers. Two missense and 2-bp frameshift somatic mutations in DPC4 were detected among 42 lung cancer specimens taken directly from patients. DPC4 mutations, however, were not present in all lung cancers carrying 18q21 deletions. These findings suggest that DPC4 may play a role in a limited fraction of lung cancers and that another tumor suppressor gene may also exist in this chromosome region.
This work was supported in part by a Grant-in-Aid for the Second Term Compre-hensive Ten-Year Strategy for Cancer Control from the Ministry of Health and Welfare, Japan; Grants-in-Aid for Cancer Research from the Ministry of Education, Science, Sports and Culture, Japan; and the Ministry of Health and Welfare, Japan.