CGH analysis of radon-induced rat lung tumors indicates similarities with human lung cancers

Epidemiological studies have shown that inhalation of radon, a radioactive gas, is associated with an increased risk for lung cancer. We have develope d a model of radon-induced rat lung tumors to characterize cytogenetic and molecular events involved in radon-induced lung tumorigenesis. Using compar ative genomic hybridization (CGH), gains and losses of genetic material wer e investigated in a series of 13 carcinomas and four adenomas of the lung. Frequent losses occurred at 4q12-21, 5q11-33, and 15q, which are homologous to human chromosome (HSA) bands 7q21-36, 1p31-36/9p21-31, and 13q14.1-14.3 /3p14.2, respectively. These regions are frequently (30-80%) deleted in hum an lung cancer acid contain tumor suppressor genes or proto-oncogenes such as MET, CDKN2A/p16IMTSI, CDKN2B/p 15/MTS2, FHIT, and RBI or yet to be ident ified genes. Frequent gains involved 6, 7q34-qter, and 19q; chromosomes 6 a nd 7 being homologous to human 2p21-25 and 8q21-24 where the MYCN and MYC o ncogenes are located. The genetic similarities between rat and human lung c ancer suggest common underlying mechanisms for tumor evolution in both spec ies. Moreover, cytogenetic and molecular genetic analyses of radon-induced rat lung tumors could help to better understand the development and progres sion of radon-induced lung cancer in man. Genes Chromosomes Cancer 29:1-8, 2000. (C) 2000 Wiley-Liss, Inc.