Swierkot et al. [51] indicated that the receptor activator of nuclear factor-κB ligand (RANKL) expression, which in RA contributes to the elevated level of osteoclast differentiation, is regulated by the IL-6/soluble IL-6 receptor, the JAK2/STAT3/SOCS-3 pathway. This evidence concerns the gene STAT3 and rheumatoid arthritis.