CD138

CD138‏‎ or Syndecan-1 is a protein that in humans is encoded by the SDC1 gene. It is a member of the syndecan family, a group of transmembrane proteoglycans that are involved in the binding of cells to the extracellular matrix, the intercellular matrix, and specific growth factors.

Structure[edit | edit source]

CD138 is a type I integral membrane protein that has a large extracellular domain, a single transmembrane domain, and a short cytoplasmic tail. The extracellular domain is heavily glycosylated and carries heparan sulfate and chondroitin sulfate glycosaminoglycan chains. The cytoplasmic domain interacts with cytoskeletal proteins, kinases, and other signaling molecules.

Function[edit | edit source]

CD138 plays a role in cell-cell adhesion, cell-matrix adhesion, cell migration, and cell proliferation. It is also involved in the organization of cell shape by influencing the cytoskeleton and the distribution of integrins. CD138 is expressed in various cell types, but it is particularly abundant in epithelial cells and plasma cells. In plasma cells, it is a marker of terminal differentiation and is used in diagnostic histopathology to identify plasmacytomas and multiple myeloma.

Clinical significance[edit | edit source]

CD138 is a valuable diagnostic marker in oncology, particularly in the diagnosis of multiple myeloma. It is also used in the diagnosis of various other tumors, including breast cancer, prostate cancer, and lung cancer. In addition, CD138 has been implicated in the pathogenesis of several diseases, including atherosclerosis, diabetes, and inflammatory bowel disease.