EZH1 and Miyoshi myopathy: Interestingly, EZH2 and its homolog EZH1 are promising targets for therapeutic intervention in MM, since small molecule inhibitors of EZH1/2 trigger cell cycle arrest and apoptosis in MM cell lines and primary CD138+ cells [25, 26, 40], and stem cells [41] as consequence of upregulation of H3K27me3-silenced genes, including the CDK inhibitors CDKN1A/p21 and CDKN2B/p15.