p53-dependent regulation of induction of angiogenic regulatory factors by proton beam in vitro

Abstract

Angiogenesis is required for the growth and progression of malignancies. Recent studies have shown that the p53 gene is one of the factors for determining cellular radiosensitivity. Previously, we have reported that the cellular radiosensitivity of wild-type (wt) p53 cells was higher than that of p53-deficient or mutant (m) p53 cells. We have also found that the radiosensitivity of wtp53 tumors was higher than that of mp53 tumors. These findings suggest that the induction or suppression of tumor environmental factors due to a p53-dependent manner may contribute to the kinetics of tumor regrowth after irradiation. However, the correlation of p53 functions and the induction of VEGF by irradiation remains unclear. In the present study using human glioblastoma cells, we found that the accumulation of VEGF was induced by proton beam irradiation in the mp53 cells, but not in the wtp53 cells. We will discuss the contribution of p53 gene to anti-tumor effects of proton beam irradiation.