Figure 5

CDK1 inhibition selectively reduced viability of MYC-dependent breast cancer cells. (A) Cells were transfected with either pooled CDK1 siRNA (siCDK1) or Non-targeting siRNA control (siCON) at 10 nM. Cell viability was measured by AlamarBlue assay 5 days post-transfection. (B) Cell apoptosis was assessed by the detection of caspase-cleaved cytokeratin 18 with M30 cytoDEATH™ using flow cytometry. (C) Cells were treated with CDK1 inhibitor RO-3306 or CGP74514A at the indicated concentrations for 3 days. Cell viability was measured by AlamarBlue assay and the data expressed as the percentage of viability relative to vehicle-treated cells. (D) Representative histograms 48 hours after treatment with RO-3306 or CGP74514A at 5 μM. *P < 0.05, **P < 0.01, ***P < 0.001, compared with cells transfected with control siRNA.