Xenograft tumor-derived cells have dysfunctional mitochondrial respiration. (A) Oxygen consumption data for the control WTHBF-6 cells (C52-2 cells) and Cr(VI)-transformed WTHBF-6 cells (T23-3 cells) and xenograft tumor-derived cells (T23-3-X2, T23-3-X3, T23-3-X4, T23-3-X5, T23-3-X6, and T23-3-X7 cells) presented as a baseline percentage to the third oxygen consumption read. (B) Basal respiration, maximal respiration, and spare respiratory capacity for C52-2, T23-3, T23-3-X2, T23-3-X3, T23-3-X4, T23-3-X5, T23-3-X6, and T23-3-X7 cells. (C) Proton leak, non-mitochondrial oxygen consumption, and coupled respiration for C52-2, T23-3, T23-3-X2, T23-3-X3, T23-3-X4, T23-3-X5, T23-3-X6, and T23-3-X7 cells. (D) Mitochondrial coupling efficiency for C52-2, T23-3, T23-3-X2, T23-3-X3, T23-3-X4, T23-3-X5, T23-3-X6, and T23-3-X7 cells. (E) Oxygen consumption data for control WTHBF-6 cells (C52-2 cells), Cr(VI)-transformed WTHBF-6 cells (T73-3 cells), and xenograft tumor-derived cells (T73-3-X2 and T73-3-X3 cells) presented as a baseline percentage to the third oxygen consumption read. (F) Basal respiration, maximal respiration, and spare respiratory capacity for the C52-2, T73-3, T73-3-X2, and T73-3-X3 cells. (G) Proton leak, non-mitochondrial oxygen consumption, and coupled respiration for C52-2, T73-3, T73-3-X2, and T73-3-X3 cells. (H) Mitochondrial coupling efficiency for C52-2, T73-3, T73-3-X2, and T73-3-X3 cells. Data are the average of at least three experiments ± SEM. *p < 0.05 from C52-2 cells. #p < 0.05 from either T23-3 or T73-3 cells.