Deletions and rearrangements of the retinoblastoma gene in hepatocellular carcinoma, insulinoma and some neurogenic tumors as found in a study of 121 tumors.

The retinoblastoma gene (Rb) is one of the tumor suppressor genes to have already been cloned. Deletions and inactivations of the gene have been widely observed in various types of human tumor. To study the generality of Rb alteration in human tumors, 121 cases of tumor DNAs were examined for abnormalities in the gene structure by blot hybridization. Deletions of both alleles were detected in hepatocellular carcinoma, insulinoma and neuroblastoma. Rearrangements and allelic deletions of the Rb gene were, moreover, observed in some brain tumors and hepatocellular carcinomas, respectively. All were surgically resected tumors. The observations suggest the inactivation of Rb through structural alterations sometimes to correlated with the development or progression of these types of human tumor.