Involvement of caspases in clerosterol-induced apoptosis. (a) The clerosterol-treated cells were separated by electrophoresis, and cleaved caspase 3, cleaved caspase 9, Bax and Bcl-2 were detected by Western blotting with the corresponding antibodies. (b) The clerosterol-treated cells, Z-VAD-FMK-treated cells, Z-VAD-FMK and clerosterol-treated cells were separated by electrophoresis, and cleaved caspases were detected by Western blotting with the corresponding antibodies. (c) The cell viability of clerosterol-treated cells, Z-VAD-FMK-treated cells and clerosterol and Z-VAD-FMK-treated cells were detected by using MTT at 24 h.