Fig. 3.

The effect of inhibitors of SMase and de novo ceramide synthesis on 4-HPR cytotoxicity in AML cells. Cells (30,000/well) in 96-well plates were preincubated for 60 min with inhibitors, GW4869, desiprimine, and FB1 at the concentrations indicated, after which 4-HPR was added for 24 h. Cell viability was determined using MTS reagent as detailed in Materials and methods. Concentrations of agents (micromolar) are given in parentheses. * denotes statistical significance with p-value ≤ 0.05.