CASP3 and hepatocellular carcinoma: Caspase 3 and PARP were cleaved in VC-treated cells (Supplementary Fig. 2f) and the VC-induced decrease in cell viability was partially recovered after pretreatment with Z-VAD-FMK, a pan-caspase inhibitor, implying that VC triggers caspase-dependent death in HCC cells (Fig. 5i and Supplementary Fig. 2e).