Dlx-2 shRNA prevents metabolic stress-induced ROS production. (A, B) MDA-MB-231 cells were stably transfected with control or Dlx-2 shRNA and treated with GD for 3 or 6 h, and mitochondrial ROS and O2- and intracellular H2O2 production was measured using the MitoTracker Red CM-H2XRos, DHE, and DCFH-DA, respectively, under a fluorescence microscope (X200; Carl Zeiss). Representative images of cells from 3 independent experiments are shown (A). The values are expressed as mean ± SE from approximately 200 cells per treatment group (n = 3) (B). *P < 0.05, **P < 0.01 versus control; #P < 0.05; ##P < 0.01 versus control shRNA.