The function and research status of osteopontin

Osteopontin (OPN) is a widely distributed O-glycosylated phosphoric acid protein, also known as secretory phosphoprotein 1, bone sialoprotein 1, Eta-1, etc., Which is expressed in the epithelium, kidney, bone and teeth, etc.It is also found in all body fluids, including blood and breast milk.OPN plays a role in many physiological and pathological processes, such as cell adhesion and migration, angiogenesis, immunology, neurodevelopment and tumor metastasis. Key words: Osteopontin; CD44; β1integrin