ATO treatment induces ROS production and dephosphorylation of Akt, which is associated with an increase of Bad and decrease of XIAP. (A) ROS generation in CEM-C1 and -C7 was quantified by fluorometry with varying concentrations of ATO as indicated. Values of 3 experiments are shown as mean (−SD); P equals .05 (Student t test). (B) ATO as single agent. CEM-C1 and -C7 cells were incubated for different times with 1 μM ATO. Western blot analysis using whole-cell extracts from a representative experiment is shown. Antiactin was used for loading control. (C) Combination for 5 hours of 0.25 μM ATO with 1 μM DEX in CEM-C1 and Jurkat cells; A indicates ATO; D, DEX.