K-ras and p53 gene alterations are frequently found in human pancreatic carcinomas and cell lines. The aim of this study was to analyze for the presence of K-ras and p53 gene mutations in hamster pancreatic tumors and cell lines. Mutations at the first coding exon of the K-ras gene and in exons V to VIII of the hamster p53 gene were analyzed in six cell lines (H2T, PC1, PC1.2, PC1.0, WD, and PD) and in N-nitroso-bis(2-oxopropyl)amine-induced pancreatic (n = 9) and extra-pancreatic (n = 4) tumors. K-ras mutations were present in seven of the nine pancreatic tumors and in all extra-pancreatic tumors. No p53 mutations were detected in the tumors. All cell lines analyzed contained K-ras mutations. Moreover, four of the six cell lines contained single amino acid substitutions in the p53 gene. Cell lines derived from nitrosamine-induced pancreatic tumors in the hamster contained K-ras and p53 alterations similar to those found in cell lines derived from human pancreatic carcinomas.