Fig. 2.

Resveratrol/HDAC inhibitors induce DNA damage, mitochondrial injury, and caspase activation in human leukemia cells. A, U937 cells were incubated with 50 μM resveratrol (RESV) with or without 15 nM LBH-589 (LBH) for the indicated periods (left) and MV-4-11 cells were exposed to 25 μM resveratrol with or without 7.5 nM LBH-589 1 μM vorinostat (Vor) for 24 h (right). After treatment, cells were lysed and Western blot analyses were performed to monitor the expression of γH2A.X. R, resveratrol; L, LBH-589. B, U937 cells were treated with 50 μM resveratrol with or without 15 nM LBH-589 or 1.5 μM vorinostat (Vor) for the indicated periods, after which the S-100 cytosolic fraction was prepared and subjected to Western blot analysis to monitor the release of mitochondrial cytochrome c (Cyto c) into the cytosol. V, vorinostat. C, U937 cells were treated for 8 h as described for B, after which comet assays were performed to assess single- and double-strand DNA breaks. Veh, vehicle. D and E, U937 (D) and MV-4-11 (E) cells were exposed to resveratrol (U937, 50 μM; MV-4-11, 25 μM) with or without LBH-589 (U937, 15 nM; MV-4-11, 7.5 nM) or vorinostat (U937, 1.5 μM; MV-4-11, 1 μM) for 24 h, after which cleavage of caspase-8, caspase-3, caspase-9, and PARP was assessed through Western blot analysis. CF, cleaved fragment; Casp, caspase. Each lane was loaded with 30 μg of protein; blots were stripped and reprobed for β-actin to ensure equivalent loading and transfer.