CD146 / MUC18 / Mel-CAM (BSB-122), MMab

Summary and Explanation

CD146 also known as the melanoma cell adhesion molecule (Mel CAM) or cell surface glycoprotein MUC18, is a 113kDa cell adhesion molecule currently used as a marker for endothelial cell lineage. In humans, the CD146 protein is encoded by the MCAM gene.

MCAM functions as a receptor for laminin alpha 4, a matrix molecule that is broadly expressed within the vascular wall. MCAM is highly expressed by cells that are components of the blood vessel wall, including vascular endothelial cells, smooth muscle cells and pericytes. It is expressed on chicken embryonic spleen and thymus, activated human T cells, endothelial progenitors such as angioblasts and mesenchymal stem cells, and strongly expressed on blood vessel endothelium and smooth muscle.

The lineage-specific expression pattern of the CD146 antibody can be useful in the differential diagnosis of certain conditions including melanomas and various types of gestational trophoblastic lesions. CD146 has been suggested to play an important role in tumor progression, implantation and placentation. CD146 antibody expression can promote tumor progression in human melanoma, possibly through enhanced interaction between melanoma cells and endothelial cells. In contrast, CD146 may act as a tumor suppressor in breast carcinoma. CD146 expression is frequently lost in breast carcinomas and overexpression of CD146 in breast carcinoma cells results in a more cohesive cell growth and the formation of smaller tumors in nude mice. During implantation and placentation, CD146 expressed by the intermediate trophoblast in the placental site binds to its putative receptor in uterine smooth muscle cells and limits trophoblastic invasion in the myometrium.