Apoptotic cells were measured via flow cytometry in K562 cells and K562-R cells under imatinib, hypoxia, and/or VitaminK3 treatment. (A, C). The cell cycle of K562 cells was evaluated via flow cytometry after these cells were subjected to hypoxia, imatinib, and/or VitaminK3 stimulation (B, D). The cell cycle of K562-R cells was analyzed after hypoxia, imatinib and/or VitaminK3 treatment. IM, imatinib. VitK3, VitaminK3. ** P<0.01; * P<0.05.