Description
The CD138 (Syndecan-1) is a transmembrane heparin sulfate–rich proteoglycans that consists of 5 glycoaminoglycans and 1 core protein. It regulates the activity of heparin-binding growth factors, induces apoptosis, and inhibits growth of myeloma. Syndecan-1 also mediates osteoclast and osteoblast differentiation and myeloma cell adhesion. Loss of syndecan-1 from the plasma cell surface may play a critical role in the proliferation and extra medullary dissemination of myeloma or recurrence after therapy. In the context of hematopoietic cell identification, CD138 is a highly specific and sensitive marker of normal and plasma cells and is expressed by lymphoid tumors with plasmacytic differentiation.