Protease-activated receptors (PARs) are a unique class of G protein-coupled receptors that play critical roles in thrombosis, inflammation, and vascular biology. The PARs are cleaved by thrombin and other proteases at a specific peptide bond to expose a new N-terminus that binds to the body of the receptor in an unusual intramolecular mode. A major interest of our research group is to study the molecular mechanism of protease activation of the PARs and the subsequent signaling in vascular cells and in cancer.