Figure 1

Effect of vitamin K1 (VK1) or sorafenib, or their combination, on cell viability of glioma cells. (A) BT325 and U251 cells were incubated with 0, 25, 50 or 100 μM VK1 for 24 h. (B) BT325 and U251 cells were incubated with 0, 2.5, 5 or 10 μM sorafenib for 24 h. (C) Cells were incubated with sorafenib (2.5 μM) plus varying concentrations of VK1 (0, 25, 50, 100 μM) for 24 h. (D) Cells were incubated with sorafenib (2.5 μM) plus VK1 (50 μM) for 24, 48, 72 h. The cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell viability was expressed as the percentage of cell survival compared with the control. Data were repeated at least three times. An asterisk indicates P<0.05 vsthe control vehicle (A,B,D), or sorafenib-induced cells without VK1 treatment (C).