Increased ROSs in FLT3/ITD cells. (A) Endogenous ROS was measured in 3 cell lines: mouse myeloid progenitor cell line 32D, 32D stably expressing exogenous wild-type FLT3 (32D/WT), and 32D stably expressing exogenous FLT3/ITD (32D/ITD). Shown are the relative ROS levels of the 3 cell lines, of which the 32D cell line was set at 100%. 32D/ITD cells exhibited a significantly higher ROS level than 32D and 32D/WT cells; the latter 2 showed comparable ROS levels. Flow cytometric histogram show ROS fluorescence results from one experiment. (B) All 3 cell lines were treated with CEP-701; the greatest decrease of ROS was observed in 32D/ITD cells, followed by 32D/WT cells; 32D cells showed the least decrease of ROSs. (C) The Ba/F3 cells stably transfected with FLT3/ITD construct (Ba/F3/ITD) showed higher ROS level than the cells transfected with FLT3/TKD construct (Ba/F3/D835Y) and Ba/F3 cells. The error bars represent plus or minus SEM.