Figure 1From: Neutral sphingomyelinase 2 modulates cytotoxic effects of protopanaxadiol on different human cancer cells Protopanaxadiol (PPD) exhibited the most potent cytotoxic effects on cancer cells of various malignancies. K562 cells were treated with PPD at 0, 25 or 50 μM for 24 or 48 hr, then their viabilities were assessed using XTT (A) and SRB assays (B). *, p < 0.05; **, p < 0.01; ***, p < 0.001 for control (vehicle) are considered as significant.Back to article page