Abstract |
Epithelial cells of the respiratory tract of rats were transformed in vitro by 7,12-dimethylbenz(a)anthracene (DMBA). Ha-ras exon 2 was amplified by the polymerase chain reaction and then sequenced directly. In 10 transformed cell lines, of which 5 are known to be tumorigenic, no mutations in the region of codon 59-61 were found. The results suggest that Ha-ras codon 61 mutations are not associated with cell transformation initiated with DMBA in this cell transformation system. These data imply other genes (oncogenes) are responsible for transformation of these cells. The results are discussed in relation to observations in various transformation systems in vivo and in vitro. (Copyright (c) 1989 Academic Press, Inc.) |