ITGB2 and plasma cell myeloma: Finally, TAMs protect myeloma cell lines and primary myeloma cells from spontaneous and chemotherapeutic drug-induced apoptosis by attenuating caspase-dependent activation and cleavage of apoptotic signals as well as P-selectin glycoprotein ligand 1(PSGL-1)/selectins and intercellular adhesion molecule 1(ICAM-1)/CD18, a pattern of cell-cell contact (117, 130).