Induction of stable p53 oncoprotein and of c-myc overexpression in cultured normal human uroepithelium by radiation and N-nitrosodiethanolamine.

Uroepithelium cultured from normal patients without cancer (60 individuals) was found to segregate into four subtypes based on the level of carcinogen treatment needed to induce abnormal p53 and c-myc. Twenty-two percent of patient cultures never showed abnormal p53 expression, even after chronic exposure to nitrosamines, in addition to irradiation. In these cultures, c-myc expression was confined to viable, normal-appearing cells at the …