Concomitant p53 gene mutation and increased radiosensitivity in rat lung embryo epithelial cells during neoplastic development.

A rat lung cell population had been treated with benzo(a)pyrene, and a set of different epithelial cell lines was derived from it. These cell lines carried either a wild-type or mutant p53 gene and represented grading states of neoplastic development. We demonstrate here that the cells lacking both wild-type p53 alleles display a significant decrease in survival after gamma-irradiation with doses of 2 to 12 Gy, compared with their counterparts carrying wild-type p53 alleles. This is the first reported model in which cells bearing a mutation of the p53 gene display enhanced sensitivity to ionizing radiation.