Vascular endothelial growth factor (VEGF) is a specific mitogen on endothelial cells and promotes angiogenesis. It has been identified that VEGF is very closely linked to the growth of solid tumors. With Dot blot technique, expression of the VEGF mRNA in cancers of stomach, kidney, bladder and colon are investigated. The results showed that the expression of the VEGF mRNA is higher in tumors than in peritumors. There is significant expression of VEGF mRNA in SGC-7901 cells after adding TPA 4h. Human bladder carcinoma cell line BIU-87 transfected with antisense N-ras exon 1 DNA fragment inhibit VEGF mRNA expression.