CASP9 and melanoma: Melanoma cells were pretreated with Caspase-9 specific inhibitor (z-LEHD-fmk, Caspase-9i) and then exposed to combination treatment, and the result showed that there was a decrease in cell death as compared to combination treatment; however, pretreatment with specific Caspase-8 inhibitor (z-IETD-fmk, Caspase-8i) did not affect the combination-induced cell death (Fig. 3).