A cell-permeable, orally bioavailable, ATP-competitive, broad-spectrum tyrosine kinase inhibitor (IC
50 against against c-Src, Wee1, FGFR-1, Myt1, EGFR, and PDGFRβ = 8.4, 24, 39.3, 72, 87.5 and 98.3 nM, respectively) that suppresses angiogenesis both
in vitro (max inhibition dose at 100 nM in HUVEC microcapillary formation assays) and
in vivo (max inhibition achieved via 5 mg/kg p.o. in murine Matrigel plug angiogenesis assays), while exhibiting much reduced potency against Chk1, MAPK, and PKC (IC
50 = 3.4, 5, and 22.7 μM, respectively) and little activity toward IRTK and Cdk4/D1 even at concentrations as high as 50 μM. Shown to effectively block PDGF-, EGF-, and bFGF-stimulated receptor phosphorylations (IC
50 = 6.5, 1600, and 97.3 nM, respectively) and other cellular responses in rat aortic smooth muscle cells. Inhibition of cellular Wee1 activity by 500 nM PD 166285 in combination with 50 ng/ml nocodazole (Cat. No.
487928) treatment is also reported to result in a blockage of radiation-induced Cdc2 phosphorylation on Tyr15 and Thr14 in 7 human cancer cells and specifically demonstrated to sensatize PA-1 cultures to radiation-induced cell death in a p53-dependent manner.