SDC1 and plasma cell myeloma: CD138 was shown to be overexpressed on the surface of multiple myeloma cells which is used in a preclinical study for an antitumoral therapy with indatuximab, a monoclonal antibody coupled with a cytotoxic agent, which is currently evaluated in preclinical studies on plasmacytoma [3] and triple-negative breast cancers in combination with other drugs [4].