Description
Osteopontin (OPN) also known as bone sialoprotein I (BSP-1), early T-lymphocyte activation (ETA-1), and Secreted phosphoprotein 1 (SPP1) is a secreted phosphoprotein that confers on cancer cells a migratory phenotype and activates signaling pathways that induce cell survival, proliferation, invasion, and metastasis.1 OPN is also considered as a proinflammatory cytokine.2 OPN has been studied as a multifunctional protein that is upregulated in a variety of acute and chronic inflammatory conditions, such as wound healing, fibrosis, autoimmune disease, and atherosclerosis. OPN is highly expressed at sites with atherosclerotic plaques, especially those associated with macrophages and foam cells.3