P53 MUTATIONS IN TUMORS INDUCED BY INTRAPERITONEAL INJECTION OF CROCIDOLITE ASBESTOS AND BENZO[A]PYRENE IN RATS

Mutation analysis of the tumour suppressor gene p53 in rumours induced in the peritoneal cavity of rats revealed differences in the mutation al pattern with regard to the carcinogenic substances applied. In rumo urs induced by benzo[a]pyrene a considerable amount of p53 mutations r esulting in an altered protein structure could be detected. For the de velopment of these tumours an escape from the p53 mediated cell cycle control can be assumed. However, in tumours of the same tumour type in duced by crocidolite asbestos no mutations could be observed. Since th ere were even no spontaneous p53 mutations detectable in this tumour g roup, it is obvious that in these rumours the escape from cell cycle c ontrol does not take place via inactivation of p53. Therefore, it is c oncluded that the molecular mechanisms of carcinogenesis and tumour de velopment in this tumour type depend on the type of carcinogen applied .