Description
PF-477736 is a selective, potent and ATP-competitive Chk1 inhibitor with Ki of 0.49 nM and also inhibitsVEGFR2, Aurora-A, FGFR3, Flt3, Fms (CSF1R), Ret and Yes. It shows ~100-fold selectivity for Chk1 than Chk2. Phase 1.
Storage
2 years -20 centigrade Powder; 2 weeks 4 centigrade in DMSO; 6 months -80 centigrade in DMSO.
Targets
ChK1, ChK2, VEGFR2, Yes, Fms
IC50
0.49 nM; 47 nM; 8 nM; 14 nM; 10 nM
Molecular Formula
C22H25N7O2
Chemical Name
Cyclohexaneacetamide, α-amino-N-[5,6-dihydro-2-(1-methyl-1H-pyrazol-4-yl)-6-oxo-1H-pyrrolo[4,3,2-ef][2,3]benzodiazepin-8-yl]-, (αR)-
Solubility
DMSO 6 mg/mL; Water <1 mg/mL; Ethanol <1 mg/mL
In vitro
PF-477736 (128 nM) abrogates the camptothecin-induced DNA damage checkpoint in a dose-dependent manner in CA46 and HeLa cells. PF-477736 effectively abrogates the gemcitabine-induced S-phase arrest with a corresponding increase in apoptotic cell populations in HT29 cells. PF-477736 (540 nM) enhances gemcitabine-induced cytotoxicity in a time- and dose-dependent manner in HT29 cells. PF-477736 potentiates the growth-inhibitory activity of a panel of chemotherapeutic agents across a broad spectrum of p53-deficient human cancer cell lines in the MTT assay. Addition of PF-477736 (360 nM) to gemcitabine-arrested cells induces a dramatic increase in the intensity of H2AX phosphorylation, reflecting a greater number of γ-H2AX molecules near sites of DNA damage. PF-477736 (0.5 nM) selectively blocks p73 and P53 phosphorylation in presence of curcumin in HL-60 cells.PF-477736 (360 nM) suppresses docetaxel-induced phosphorylation of histone H3 (Ser10) and Cdc25C (Ser216) and potentiates apoptosis in COLO205 cells.PF-477736 (250 nM) combined with MK-1775 has marked synergistic cytotoxic activity in OVCAR-5 cells. PF-477736 (250 nM) combined with MK-1775 causes accumulation of cells with a DNA content between 2N and 4N in OVCAR-5 cells. PF-477736 (250 nM) combined with MK-1775 causes premature mitosis before the end of DNA replication, with damaged DNA leading to apoptotic cell death in OVCAR-5 cells.
In vivo
PF-477736 (4 mg/kg i.v.) results in terminal half-life (T1/2) of 2.9 hours, AUC of 5.72 μg×hr/mL and CLp of 11.8 mL/min/kg in rats. PF-477736 dose-dependently enhances the antitumor activity of a maximum tolerated dose of gemcitabine in the Colo205 xenograft mouse model. PF-477736 (12 mg/kg) induces an increase in the phosphorylation of histone H3 (Ser10) and of phospho-histone H2AX in the Colo205 xenograft mouse model. PF-477736 (15 mg/kg i.p.) enhances docetaxel induced tumor growth inhibition and tumor growth delay in COLO205 and MDA-MB-231 xenograft models.PF 477736 (10 mg/kg once daily i.p.) combined with MK-1775 (30 mg/kg twice a day oral) leads to greater tumor growth inhibition in mice bearing OVCAR-5 xenografts.