Skip to main content
. 2018 Jul 13;9(54):30450–30464. doi: 10.18632/oncotarget.25765

Figure 4. Chk1 inhibitor PF477736 re-sensitizes PLX4032-resistant melanoma cells to PLX4032.

Figure 4

The melanoma cells were treated with Chk1i (PF477736, 0.15 μM) in combination with increasing concentrations of BRAFi (PLX4032, 0–20 μM) as indicated on the X-axis. Cell viability (A and B) and colony formation (C and D) were measured as described in MATERIALS AND METHODS. A375-PLX-R cells form more colonies in the presence of 2.5–15 μM PLX4032 than in the absence of PLX4032 (Figure 4D, green curve). The error bars reported are the standard deviations of the averages from triplicates of three independent experiments. Combination index (CI) for cells treated with two drugs was determined by CompuSyn software for Chou and Talalay analysis as described [54]. One, two, and three ♠ represent CI (0.5–0.9), CI (0.25–0.5), and CI (<0.25), respectively.