[Influence of the thymidine phosphorylase (platelet-derived endothelial cell growth factor) on tumor angiogenesis. Catalytic activity of enzyme inhibitors].

Thymidine phosphorylase, also known as platelet-derived endothelial cell growth factor, is a potent angiogenic factor. Thymidine phosphorylase is overexpressed in various human tumors and plays an important role in angiogenesis. A novel inhibitor of thymidine phosphorylase (TP), 5-chloro-6-[1-(2-iminopyrrolidinyl) methyl] uracil hydrochloride (TPI) is about 1000-fold more active than 6-amino-5-chlorouracil, one of the most potent TP inhibitors to 1999 year. Thymidine phosphorylase is also inhibited by 5'-O-trityl-inosine (KIN59) and related compounds, 2-deoxy-L-ribose and glycosides isolated from the bark of Symplocos racemosa.