Angiogenesis is controlled by a local balance between stimulators and inhibitors of new vessel growth and is suppressed;under normal physiologic conditions. Angiogenesis has been shown to be essential for growth and metastasis of solid;tumors. In order to obtain blood supply for their growth, tumor cells are potently angiogenic and attract new vessels;as results of increased secretion of inducers and decreased production of endogenous negative regulators. BAI1;contains at least one functional p53-binding site within an intron, and its expression has been shown to be induced;by wildtype p53. There are two other brain-specific angiogenesis inhibitor genes, designated BAI2 and BAI3 which along;with BAI1 have similar tissue specificities and structures, however only BAI1 is transcriptionally regulated by p53.BAI1 is postulated to be a member of the secretin receptor family, an inhibitor of angiogenesis and a growth;suppressor of glioblastomas.