In addition, the activity of synovial cells such as macrophages, fibroblast-like synoviocytes (FLS), chondrocytes, and endothelial cells is regulated by the uPA/uPAR interaction, allowing them to secrete a variety of cytokines, chemokines, and growth factors that alter the prognosis of RA [15]. Here, PLAUR is linked to rheumatoid arthritis.