Protease activated receptor 1 (PAR-1) belongs to a subfamily of G-protein coupled receptors and is known to mediate the cellular effects of thrombin. This peptide is a PAR-1 selective agonist displaying a high level of specificity to PAR-1 over PAR-2. The specificity of peptide was evaluated in cell-based calcium signaling assay using HEK293 cells. PAR-1 selective agonists can be used to study PAR-1 activation in vivo. In addition to its varied cellular effects of thrombin, PAR-1 has also been shown to coordinate with PAR-4 and regulate thrombin-induced hepatocellular carcinoma harboring thrombin formation within the tumor environment classified as 'coagulation type'.