Loss of mitochondrial membrane potential. Flow cytometry to detect change/loss in ΔΨ_m was performed on live cells following 5-hour exposure to MGd and ascorbate in the (A) dexamethasone-sensitive cell line, C2E3, the (B) dexamethasone-resistant cell line, 1-310, the (C) highly dexamethasone-resistant cell line, 1-414, the (D) chemotherapy-sensitive cell line, 8226-RPMI, and the (E) highly chemotherapy-resistant line, DOX-10V. Dead cells were gated out with PI. Results show percentage of cells staining with CMXros, with lower percentages indicating loss of ΔΨ_m. Results shown (means and SD) were averaged from 3 or more independent experiments done in triplicate for each time point.