Figure 3. 2DG-ABT induced apoptosis is a non-canonical mitochondria-dependent form of apoptosis.

a, Wt, and Bax/Bak DKO MEFs were treated with 10 mM 2DG for 3 hours before the addition of 3 µM ABT-263 for 3 hours. 3 hours later, cells were harvested for caspase activity assays. (See also Fig. S5a). b, HT1080 cells were treated with or without 2DG for 3 hours. Then cells were treated with either 1 µM STS or anti-Fas (CD95) antibody at indicated concentrations (µg/ml). Cells were harvested 3 hours after, and assayed for caspase activity. Interestingly, 2DG seems to have interfered with Fas-induced apoptosis. In repeated experiments, we observed consistently lower rates of caspase activation in 2DG pre-treated cells, but the degrees of inhibitory activity varied from experiment to experiment. We are not sure of its cause. c, For the first 3 hours, HeLa cells were either treated with 10 mM 2DG or left untreated and then treated with 10 µM z-VAD, 1 µM ABT-737, both, or neither for 3 more hours. The cells were fixed and stained for DNA (red) and cytochrome c (green) and examined for loss of cytochrome c staining, as described in Methods. Bar indicates 100 µm. The representative images are shown in Fig. S3. This graph shows the percentage of cells with loss of cytochrome c staining. The combination treatment had higher rates of cells with released cytochrome c (p = 0.008 by unpaired t-test ). d, Cells treated as in c were fractionated and cytosolic fractions were analyzed by western blots.