CYC116, the most aurora-selective aurora kinase inhibitors, can inhibit aurora A and B kinases about 50-fold more potently than any of the CDKs assayed. CYC116 inhibits two tyrosine kinases, FMS-like tyrosine kinase 3 (FLT3) and vascular endothelial growth factor receptor 2 kinase (VEGFR2), with a Ki value of 44 nM. CYC116 shows no inhibition to PKA, Akt/PKB, PKC, GSK-3alpha, GSK-3beta, ERK2, CaMKII, CK2, Plk1 and SAPK2A. CYC116 shows low micromolar activity against 70 kDa ribosomal protein S6 kinase (p70S6K), Src, and lymphocyte-specific protein tyrosine kinase (Lck). CYC116 is particularly cytotoxic against the acute myelogenous leukemia cell line MV4-11. Treatment with 1.25 uM CYC116 for 7 h results in complete inhibition of histone H3 phosphorylation. CYC116 inhibits autophosphorylation of both aurora A and B(66) at antiproliferative concentrations in cells. [1]
In vivo
In the P388/D1 murine leukemia model, oral dosing at 45 and 67 mg/kg twice daily on days 1?5 and 7?9 resulted in a significant increase in lifespan (ILS) of 172% and 183%, respectively. In NCI-H460 xenografts, at dose levels of 75 and 100 mg/kg q.d. causes tumor growth delays of 2.3 and 5.8 days, which translated into specific growth delays of 0.32 and 0.81, respectively. [1]