UCN-01 is a synthetic derivative of staurosporine with antiproliferative activity against several in vitro and in vivo cancer models. It inhibits a variety of kinases, including Akt, protein kinase C (IC50 = 30 nM), PDK1 (IC50 = 6 nM) and cyclin-dependent kinases (IC50s = 300-600 nM for Cdk1 and Cdk2). UCN-01 arrests tumor cells in the G1/S phase of the cell cycle and prevents nucleotide excision repair by inhibiting the G2 checkpoint kinase Chk1 (IC50 = 7 nM), leading to apoptosis.
