SU9516

SU9516 is a potent CDK2 inhibitor, with an IC₅₀ of 22 nM, and also shows inhibitory effects on CDK1 and CDK4, with IC₅₀s of 40, 200 nM, respectively. IC50 & Target: IC50: 22 nM (CDK2), 40 nM (CDK1), 200 nM (CDK4)^[1] In Vitro: SU9516 shows slight activities against PKC, p38, PDGFr and EGFR, with IC₅₀ of >10, >10, 18, and >100 μM. SU9516 (5 μM) decreases cdk2-specific Phosphorylation of pRB and inhibits cell cycle progression in RKO cells. SU9516 (5 μM) also induces apoptosis in RKO and SW480 Cells^[1]. SU9516 (5 μM) results in enhanced pRb/E2F complex formation in HT-29 cells. SU9516 enhances presence of E2F species in multiprotein complexes^[2]. SU9516 (5 μM) rapidly induces cytochrome crelease, Bax mitochondrial translocation, and apoptosis in association with pronounced down-regulation of the antiapoptotic protein Mcl-1. SU9516 causes down-regulation of Mcl-1 mRNA levels in human leukemia cells. Furthermore, SU9516 treatment results in a marked increase in reactive oxygen species production^[3].