Role of CD73 in Disease: Promising Prognostic Indicator and Therapeutic Target.

CD73, also known as ecto-5'-nucleotidase (eN, NT5E, EC3.13.5), is the ratelimiting enzyme for adenosine generation and is expressed on multiple cells. Its expression is significantly influenced by hypoxia and inflammatory factors. During inflammation, CD73 protects endothelial barrier function and inhibits leukocyte trafficking. CD73 also promotes M2 macrophages (anti-inflammatory phenotype). In addition, CD73 is expressed on Treg cells and mediates immune suppression through adenosine. CD73 serves as an essential regulator for the immunity and inflammation. Its expression is related to many diseases, such as autoimmune diseases, ischemia-reperfusion injuries, arterial calcifications, and atherosclerosis. CD73 is overexpressed in many cancers. Its expression is positively associated with tumor growth, metastasis, angiogenesis, poor prognosis and resistance to chemotherapy. Thus, CD73 may be used for prognostic indicator and therapeutic target in diseases such as cancers.