FIGURE 6.

Fatty acid and glutamine depletion sensitizes c-Myc cells to glycolysis inhibition. A, fatty acid β-oxidation was measured by the conversion of ³H-labeled palmitic acid into ³H₂O. Data shown are average of three experiments ± S.D. (*, p < 0.05). B, cells were preconditioned in media in which regular FBS was substituted with dialyzed FBS. Cells were cultured with 4-OHT to activate c-Myc and then treated with 6 mm 2-DG. Cell viability was determined by PI exclusion. Data shown are average of three experiments ± S.D. (*, p < 0.05). C, cells were cultured in media with regular FBS, and c-Myc was activated by the addition of 4-OHT. Cells were treated with 6 mm 2-DG only, or in combination with CPT1 inhibitor etomoxir (ETOM, 0.2 mm) that was added 30 min prior to the treatment of 2-DG. Cell viability was determined by PI exclusion. Data shown are average of three experiments ± S.D. (*, p < 0.05). D, cells were cultured in medium with or without glutamine and treated with 6 mm 2-DG. Cell viability was determined by PI exclusion. The cell death curve induced by glutamine deprivation is also shown (solid triangle). Data shown are average of three experiments ± S.D. (*, p < 0.05 for comparisons of cell viability between glutamine-free and glutamine-free plus 2-DG treatment).