For immunoblotting, apoptosis and DNA content analysis, cells were synchronized with double thymidine block. Cells were released for 2 hours in fresh media and treated with GSK461364 (G), GSK461364 + docetaxel (G+D) at the IC50 concentrations, and DMSO (control). (A) Immunoblotting of Plk1, FoxM1, Cyclin B1, CDK1, Phosphorus-histone H3 (Ser10), Cleaved PARP (89KDa), and β-actin were repeated at 8, 24, and 48 hours. For DNA content analysis, SUM149 (B) and SUM159 (C) cells were collected at 8, 24, and 48 hours and stained with propidium iodide. Data were acquired on BD Fortessa X-20 Analytic Flow Cytometer and analyzed with FlowJo. DNA copy content data showed in B and C were summarize in the histograms in D.