Figure 4

MYC-dependent osteogenic sarcoma cells are dependent on glucose and glutamine for survival. Doxycycline (20 ng/mL) was added to MYC-dependent osteogenic sarcoma cells and incubated for 48 hours. Subsequently, cells were placed in complete media or in media depleted of glucose, glutamine or both. (a) Cell death was assessed after 48 hours. N = 3 ± SEM * P < 0.05 compared to media containing both glucose and glutamine. (b) Cell number was assessed after 24 hours. N = 3 ± SEM * P < 0.05 compared to media containing both glucose and glutamine. (c) Cytosolic ROS was measured after 24 hours using roGFP2. N = 4 ± SEM * P < 0.05 compared to media containing both glucose and glutamine. (d) Cell death was assessed in osteogenic sarcoma cells depleted with glutamine and supplemented with galactose (10 mM), pyruvate (5 mM) and/or NAC (1 mM). N = 3 ± SEM * P < 0.05 compared to media containing both glucose and glutamine. (e) Cell death was assessed in osteogenic sarcoma cells depleted with glutamine and supplemented with DMK (5 mM) and/or NAC (1 mM). N = 4 ± SEM * P < 0.05 compared to media containing no glucose and no glutamine. (f) Cell cycle analysis at 48 hours in osteogenic sarcoma cells simultaneously treated with DMK and doxycycline. N = 3 ± SEM * P < 0.05 compared to 0 ng/ml doxycycline. (g) Phase contrast microscopy pictures of osteogenic sarcoma cells treated with DMK (0–5 mM), glutamine (4 mM) and doxycycline.