B2M and cancer: Previous studies have demonstrated that β2M enhances the growth and survival of cancer cells through the activation of protein kinase A (PKA)/cAMP-responsive element binding protein (CREB)/vascular endothelial growth factor (VEGF) signaling pathway and cell survival signaling, including the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK) pathways [10–13].