The phosphatidylinositol 3-kinase (PI3K) signaling pathway is considered as a central regulator of macrophage polarization process.20-24 It has been accepted that this signaling pathway involves in many processes in the MM disease and can be activated by many secreted cytokines in the MM microenvironment, including IL-6, IGF-1, VEGF and CXCL12.25 Accordingly, several studies have exhibited the potential of PI3K signaling pathway manipulation to control either the survival and proliferation of MM cells or the polarization of macrophages.21,26-29. Here, CXCL12 is linked to Miyoshi myopathy.