Figure 2. Mutant EGFP–K-Ras proteins have variable effects on CC3 induction that correlate with resistance to AC220 in MOLM-13 KRAS^KO clone 24 cells.

(A) Percentages of CC3⁺ clone 24 cells were measured by flow cytometry after exposure to DMSO (control) or 10 nM AC220 in the absence (left) or presence (right) of 2 μg/mL dox for 48 hours. AC220 efficiently induces apoptosis in the absence of dox-induced K-Ras expression, which is variably suppressed by expressing different K-Ras proteins. Aggregated CC3 results for clone 24 over 3 independent experiments each performed in technical triplicate. (B) CTG analysis of cells expressing the indicated K-Ras proteins that were exposed to 2 μg/mL dox and a range of AC220 concentrations for 72 hours. For clarity, data for T50 and D154 mutants are plotted separately. (C) Normalized IC₅₀ values for 3 independent CTG experiments that were each performed in technical triplicate. Values shown are mean ± SEM. Multiple t tests were performed using the Holm-Šidák method to correct for multiple comparisons. Adjusted P values: ****P < 0.0001, ***P ≥ 0.0001 and < 0.001, **P ≥ 0.001 and < 0.01, *P ≥ 0.01 and < 0.05.