PF-562271 is a potent, ATP-competitive, reversible inhibitor of FAK with IC50 of 1.5 nM, ~10-fold less potent for Pyk2 than FAK and >100-fold selectivity against other protein kinases, except for some CDKs.
PF-562271 binds in the ATP-binding cleft of FAK, forming two of the three “canonical” H-bonds between the inhibitor and main-chain atoms in the kinase hinge region. PF-562271 is potent in an inducible cell-based assay measuring phospho-FAK with IC50 of 5 nM. PF-562271 (3.3 μM) results in G1 arrest of PC3-M cells.PF-562271 (1 nM) blocks bFGF-stimulated blood vessel angiogenesis as performed in chicken chorioallantoic membrane assays. PF-262271 potently blocks blood vessel sprouting without detectable changes in vascular leakage.PF-562271 (250 nM) results in complete inhibition of collective A431 cell invasion into collagen gels.
PF-562271 (< 33 mg/kg p.o.) inhibits FAK phosphorylation in tumors in a dose- and time-dependent manner in U87MG-bearing mice. PF-562271 (50 mg/kg p.o. bid) results in 86% tumor growth inhibition in BxPc3 xenografts mice and 45% tumor growth inhibition in PC3-M xenografts mice. PF-562271 (25 mg/kg, bid) results in 2-fold greater apoptosis in treated tumors in mice bearing H125 lung xenografts.PF-562271 (33 mg/kg, p.o.) inhibits extensive movement of the tumor cells over 24 hours in mice. PF-562271 (33 mg/kg, p.o.) results in altered E-cadherin dynamics in mice, which correlates with reduced E-cadherin–dependent collective cell movement.PF-562271 (25 mg/kg, p.o. bid) results in 62% tumor growth inhibition in PC3M-luc-C6 subcutaneuous local implant xenograft mouse model.PF-562,271 (5 mg/kg, oral) results in significant and similar increases in osteocalcin and cancellous bone parameters and a decrease in tumor growth and signs of bone healing in rats implanted with MDA-MB-231 cells in the tibia. |
