Differential dependency of human cancer cells on vascular endothelial growth factor-mediated autocrine growth and survival.

Analysis using the public microarray database Gene Expression Omnibus indicates significantly higher mRNA expression of VEGF and VEGFRs in colorectal cancer and high grade astrocytoma but not in hepatocellular carcinoma compared to normal tissue. Human malignant astrocytoma cell lines (U251-MG and U373-MG) and HT-1080 fibrosarcoma cells expressed relatively higher levels of VEGF and VEGFRs compared to hepatocellular and colorectal cancer cell lines. Administration of exogenous VEGF-A induced cell growth in a dose-dependent fashion in astrocytoma and fibrosarcoma cells but not in colorectal and hepatocellular cancer cells. The blockade of VEGF inhibited cell survival only in U251-MG, U373-MG and HT-1080 cells. These results collectively suggest the role of autocrine VEGF signaling in various cancer cells and provide a basis for the variable clinical responses to antiangiogenic therapy observed in different types of malignancies.