SATO, K., TERADA, K., SUGIYAMA, T., TAKAHASHI, S., SAITO, M., MORIYAMA, M., KAKINUMA, H., SUZUKI, Y., KATO, M. and KATO, T. Frequent 4verexpressionof Vascular Endothelial Growth Factor Gene in Human Renal Cell Carcinoma. Tohoku J. Exp. Med., 1994, 173 (3), 355-360-Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an inducer of an-giogenesis. Expression of the VEGF gene was investigated in 20 patients with renal cell carcinoma by Northern blot hybridization analysis. Of the 20 tumors, 2 (60%) overexpressed the gene 3.0 times more than in normal renal tissues. No significant correlation was found between overexpression of the VEGF gene and the histopathological data such as grade, cellular and structural subtypes, stage and size of tumor. These results suggest that VEGF is produced by the tumor cells and is responsible for development of this hypervascular tumor.