Transient expression of myrAkt impairs the sensitizing effect of ATO on dexamethasone-mediated cell death. (A) Dominant-active myrAkt was transiently expressed in CEM-C1 cells. MyrAkt rendered cells completely resistant to dexamethasone treatment and reduced the effect of 0.25 μM ATO on the cytotoxic effect of increasing DEX concentrations (0.1 μM, 1.0 μM, 7.6 μM). Values from triplicate MTT assays are shown as mean plus or minus SD. (B) myrAkt expression in CEM-C1 cells enhances the levels of Ser136 p-Bad and restores XIAP. Cells were treated as indicated 24 hours after transfection. Whole-cell extracts were obtained after 5 hours of drug exposure and analyzed by Western blot.