ROS generation and effects of NAC treatment on modulation of Bcl-2, XIAP, caspases and PARP proteins by DATS in U937 cells. (A) Cells treated with 20 μM of DATS for the indicated times were incubated with 10 μM of DCFDA at 37°C for 20 min, and ROS generation was measured using a flow cytometer. Results are expressed as the mean of two independent experiments. (B) Cells were treated with or without NAC (10 mM) for 1 h before challenge with 20 μM of DATS for 48 h. Cellular proteins were then lysed and separated by SDS-polyacrylamide gels and transferred onto nitrocellulose membranes. Membranes were probed with the indicated antibodies. Proteins were visualized using an ECL detection system. Actin was used as an internal control.