In vitro activity: APO866 at low concentrations ranging from 0.09-27 nM induces dose-dependent cytotoxicity in 41 hematologic malignant cells including acute myeloid leukemia [AML], acute lymphoblastic leukemia [ALL], mantle cell lymphoma [MCL], chronic lymphocytic leukemia [CLL], and T-cell lymphoma. APO866 at low concentrations ranging from 0-10 nM induces cell death, this effect is independent of caspase activation but is associated with depolarization of mitochondrial membrane. APO866 at concentrations ranging from 0-10 nM dose-dependently induces depletion of intracellular NAD and ATP contents and cell death in various hematologic cancer cells. APO866 at concentration of 10 nM inhibits PBEF-induced secretion of MMP-3, CCL2, and CXCL8 in HFFF2 cells.

Cell Assay: For MTT assays, 0.5 × 106 cells/mL is plated in triplicate on 96-well plates. APO866 (0.01 nM-100 nM) is added in 50 μL of culture medium, with culture medium alone serving as control. After 72 or 96 hours of incubation, 15 μL of dye solution is added to each well and cells are incubated for an additional 4 hours. Stop solution (100 μL/well) is added for 1 hour and the absorbance is read at 570 nm on a spectrophotometer. For trypan blue dye exclusion staining, 0.5 × 105 cells/well is grown in 6-well plates with 1 mL media in the absence or presence of APO866 for 96 hours. Cells from each sample are incubated with 10 μL trypan blue solution (at a 1:1 ratio [vol/vol] for 1 minute). Cell survival is determined by calculating proportion of live (unstained) cells.