Negatively regulates TNF-alpha-induced pro-inflammatory response in endothelial cells (ECs) via inhibition of TNF-alpha-induced NF-kappaB activation in ECs (PubMed:25193116). Positively regulates lipid accumulation in adipose cells (By similarity). Homodimer. Expressed in umbilical vein endothelial cells (HUVEC), and at lower levels in aortic smooth muscle cells (HASMC). Up-regulated by pioglitazone and down-regulated by TNF in HUVEC.