AICAR-activation of AMPK mediates apoptosis in ALL cells via the mitochondrial pathway. (A) DNA fragmentation assay. CCRF-CEM, NALM6, REH, and SupB15 cells were treated for 48 h with increased concentrations of AICAR (0 – 2 mM), and nuclear DNA was analyzed by electrophoresis on a 1.6% Tris-Borate-EDTA agarose gel. (B) Western blot analysis of cytochrome C and caspase 9 expression in CCRF-CEM and NALM6 cells treated for 48 h with 0.5 mM AICAR alone, 0.1 μM iodotubericidin alone (Iodo), or both agents together (Iodo + AICAR). Equal amount of loaded protein (50 μg) was confirmed by immunoblotting with anti-β-actin antibody. The data shown are representative of 3 experiments.