FC101 induces caspase-dependent apoptosis.

<p>(A–D) COS7 cells, pretreated with or without Z-VAD-FMK (10 µM) for 1 h, were incubated with FC101 at indicated concentrations for 24 h, followed by caspase 3/7 activity assay (A), for 48 h, followed by trypan blue exclusion assay (B), or for 72 h, followed by Annexin V-FITC/PI staining and flow cytometry (C, D). (C) Histograms from a representative experiment show the effect of Z-VAD-FMK on FC101-induced apoptosis of COS7 cells. The percentages of necrotic, late apoptotic, viable, and early apoptotic cells are displayed in Q1, Q2, Q3 and Q4, respectively. (D) Bar graphs show that Z-VAD-FMK partially prevented FC101-induced apoptosis of COS7 cells. Quantitative results (Q2+Q4) were displayed as fold change compared with control. For (A), (B), and (D), data represents mean ± SE (n = 3). ^a<i>P</i><0.05, ^b<i>P</i><0.01, ^c<i>P</i><0.001, difference with the control group (FC101 = 0 µM). ^d<i>P</i><0.01, difference with Z-VAD-FMK group.