Staurosporine

Model apoptosis inducer. Potent cell-permeable inhibitor of a variety of protein kinases, e.g. protein kinase C (PKC), CDK1/cyclin B (IC₅₀~5nM), CDK2/cyclin A (IC₅₀=7nM), CDK4/cyclin D (IC₅₀=3-10µM), CDK5/p25 (IC₅₀=4nM), GSK-3β (IC₅₀=15nM), Pim-1 kinase (IC₅₀=10nM).Binds do the ATP binding domain. Did not inhibit PKC-ζ. At 1µM induced apoptosis in CHO cells. Inhibits topoisomerase II directly by blocking transfer of phosphodiester bonds from DNA to active site tyrosine.