Description
Endothelial cell-specific molecule1 (ESM-1), is a secreted cysteine-rich dermatan sulfate (DS) proteoglycan primarily expressed by endothelial cells within the vascular capillary network in kidney and in the alveolar walls of the lung. ESM-1 expression has also been detected in different epithelia and in adipocytes. The expression of ESM-1 is up-regulated by TNFα, IL1β or lipopolysaccharide and down-regulated by IFNγ. The human ESM-1 gene encodes a 184 amino acid (aa) residues precursor protein with a 19 aa hydrophobic signal peptide and a 165 aa mature region with 18 Cysteine residues. The DS chain is covalently attached to serine 137. ESM-1 has been shown to bind CD11a/CD18 integrin (also known as lymphocyte function-associated antigen1, LFA1) on human lymphocytes, monocytes and Jurkat cells, inhibiting its binding to ICAM1 and reducing LFA1mediated leukocyte activation. Endocan binds via its DS chain to hepatocyte growth factor (HGF) to enhance HGF mitogenic activity. Genetically engineered cells overexpressing ESM-1 have been shown to induce tumor formation, suggesting that ESM- may be involved in the pathophysiology of tumor growth in vivo