MAPK3 and Miyoshi myopathy: Since CXCL12-mediated chemotaxis of MM cells involves PLC, PI3K, RhoA, NF-κB and ERK1/2, we specifically investigated the phosphorylation status of PLCβ3, AKT, IκBα and ERK1/2 and the activation status of RhoA (an important protein for the adhesion of MM cells) following the stimulation of MDN cells with CXCL12 (Figure 2).