Cell cycle was analyzed according to Lohberger et al. report60. Briefly, after incubation with the respective IC10, IC30, IC50 concentrations of Cos, Dehy, CD, or VOSL for 48, cells were harvested by trypsinisation, and then were fixed by ice-cold ethanol (70%) for 10 min at 4 °C. After washing with PBS, the cell pellets were resuspended in propidium iodid (PI) staining buffer (50 μL/mL PI, RNAse A; Beckman Coulter). After 15 min of incubation at 37 °C, cell cycle distribution was analyzed by a FACScalibur System (BD Biosciences) using ModFit software.