In addition, we looked at the activation of different signaling pathways in myeloma cells in an acidic condition, including PI3K-Akt, JAK-STAT3, NF-κB, ERK, p38MAPK and stress activated protein kinase-1 (JNK) pathways, and found the phosphorylation of STAT3, p65 and JNK aside from PI3K in MM cells cultured at pH6.8 (Figure 1A). This evidence concerns the gene MAPK8 and plasma cell myeloma.