Wild-type p53 and v-Src exert opposing influences on human vascular endothelial growth factor gene expression

Abstract

Angiogenesis, the development of new capillaries, is tightly controlled by the balance of positive and negative regulatory pathways. A newly described angiogenic factor, vascular endothelial growth factor/vascular permeability factor (VEGF/VPF), binds exclusively to endothelial cells and promotes their proliferation. Here we have studied the role of p53, a tumor suppressor, and v-Src, an oncogene on VEGF regulation. Wild-type p53 down-regulated endogenous VEGF mRNA level, as well as VEGF promoter activity, in a dose-dependent manner, whereas mutant forms of p53 had no effect. Overexpression of v-Src, known to up-regulate VEGF expression, activated a VEGF promoter-luciferase construct in a dose-dependent manner. Moreover, v-Src, in the presence of wt-p53, was unable to activate transcription of the VEGF promoter. Collectively, these data suggest that wild-type p53 may play a role in suppressing angiogenesis.