Absence of MDM-2 gene amplification in experimentally induced tumors regardless of p53 status.

ABSTRACT

To assess the generality of the hypothesis that murine double-minute-2 (MDM-2) gene amplification complements the absence of p53 mutation during tumor development, we analyzed 143 murine tumors induced by a variety of carcinogenic agents in two different mouse strains. Only three of 143 tumors showed p53 genetic alterations and none showed MDM-2 amplification, indicating the existence of alternative pathways that permit tumor cells to bypass p53-MDM-2 control.