CAR: A key regulator of adhesion and inflammation

- CAR dimerises across cell-cell junction sites and regulates adhesion dynamics.
- Phosphorylation of CAR regulates cell-cell adhesion stability.
- CAR can hetero-dimerise with JAM proteins on leukocytes to promote transmigration and inflammation.
- CAR is upregulated in cancer and may contribute to solid tumor growth.

The coxsackie and adenovirus receptor (CAR) is a transmembrane receptor that plays a key role in controlling adhesion between adjacent epithelial cells. CAR is highly expressed in epithelial cells and was originally identified as a primary receptor for adenovirus cell binding. However, studies over the last 10 years have demonstrated that CAR plays a key role in co-ordinating cell-cell adhesion under homeostatic conditions including neuronal and cardiac development and cell junction stability; it has also been implicated in pathological states such as cancer growth and leukocyte transmigration during inflammation. Here we provide an overview of the functions of CAR as an adhesion molecule and highlight the emerging important role for CAR in controlling both recruitment of immune cells and in tumorigenesis.