The same set of marine-derived drugs proved to be growth-inhibitory in human MM xenografts in vitro and in vivo. Plitidepsin blocks cell proliferation by arresting the cells in transition from G0/G1 to S phase and triggers apoptosis by inducing cytochrome c release and activating caspase 9 and 3 [10]. This evidence concerns the gene CASP9 and Miyoshi myopathy.