F2R and melanoma: Physiologically, PAR-1 is expressed by different tissues including vascular cells, neurons, fibroblasts, epithelial cells and others.8 PAR-1 has been shown to be overexpressed in various human cancers including breast, melanoma, colon, prostate, ovarian, esophagus and others9 and has been associated with several pro-tumoral responses including primary growth, aggressive behavior, invasion, metastasis and angiogenesis.10,11