TNFSF11 and rheumatoid arthritis: RA-derived FLS, which is characterized by vigorous proliferative capacity, anti-apoptotic effects, IL-6 production, receptor activator of NF-κB ligand (RANKL) expression, and C–X–C motif chemokine (CXCL) production, play significant roles in inflammatory synovial lesions [22, 23].