PDGF Receptor Tyrosine Kinase Inhibitor
Tyrphostin AG1296 is a tyrosine kinase blocker which selectively inhibits platelet-derived growth factor (PDGF) alpha- and beta-receptor kinases and the PDGF-dependent signaling in many cell types. Tyrphostin AG1296 also inhibits the PDGF dependent transactivation of the P2Y and Endothelin receptors-evoked cell proliferation and MA5/PK activation. This PDGF receptor (PDGFR) blocker has no effect on epidermal growth factor (EGF) receptor autophosphorylation; weak effects on DNA synthesis stimulated by insulin, by EGF, or by a combination of both; and over an order of magnitude weaker blocking effect on fibroblast growth factor-dependent (FGF) DNA synthesis. Tyrphostin AG1296 also potently inhibits the signaling of stem cell factor (SCF) receptor (c-Kit) and its upstream effector Kit receptor tyrosine kinase and the tyrosine kinase activity of FLT3-ITD which both have a strong sequence similarity with other members of the class III receptor tyrosine kinase but has no effect on theautophosphorylation of vascular endothelial growth factor (VEGF) receptor.