CASP8 and hepatocellular carcinoma: FTS pretreatment significantly enhanced the DHA/ARS-induced increase in the ICFP/IYFP/Venus ratio of cells expressing FRET-Bid and SCAT9 respectively (Fig 4), further demonstrating that FTS significantly promoted DHA/ARS-induced caspase-8 and -9 activations and subsequent apoptosis in HCC cells.