CXCR4 and Miyoshi myopathy: Although CXCR4/SDF-1 activation and MM-related bone disease are clearly associated (Zannettino et al, 2005; Bao et al, 2013), it is evident that SDF-1 engages CXCR4 on MM cells favoring their recruitment to the BM by affecting migration, adhesion, and extravasation (Parmo-Cabanas et al, 2004; Aggarwal et al, 2006; Alsayed et al, 2007).