An increased expression of SphK2 was found in MM cells as well as in MM patient PCs, where short hairpin RNA-mediated knock-down, or pharmacological inhibition of SphK2 by the selective inhibitor ABC294640, induced apoptosis via caspase-3 activation, overcoming the protective effect of BMSCs; additionally, ABC294640 enhanced c-Myc proteasome degradation [119]. Here, MYC is linked to Miyoshi myopathy.