CD146 (MCAM, melanoma cell adhesion molecule) is a receptor for laminin alpha 4, a matrix molecule expressed within the vascular wall, including within vascular endothelial cells, smooth muscle cells, and pericytes. It functions as part of the endothelial junction with the actin cytoskeleton. It is expressed in T cells, vascular endothelium, smooth muscle, adipocytes, the cerebellum, mesenchymal stem cells, activated T-cells and a subset of B cells. MCAM has been associated with the inhibition of breast cancer progression. It is also expressed in melanomas and nevi but not normal melanocytes. References: Biochim Biophys Acta 2009, 1795(2): 130; Blood 2005, 106(8):2923, Exp Hematol 2008 36(5):642.