We demonstrate that specific inhibitors of these caspase-3, -8 and -10 and the pan-caspase inhibitor ZVAD-FMK reduced the cleavage of MLKL in bortezomib-treated MM cells (Figures 4B–D) and endogenous MLKL from MM cells was found to be cleaved by recombinant caspase-8 (Figure 5), indicating the involvement of caspases in the cleavage of MLKL. This evidence concerns the gene CASP8 and Miyoshi myopathy.