Induction of receptor activator of nuclear factor kappa-B ligand (RANKL) by CXCL10 in rheumatoid arthritis (RA) synoviocytes (reverse transcriptase-polymerase chain reaction). CXCL10 (10 ng/mL) induced RANKL in RA synoviocytes. Tumor necrosis factor-alpha (TNF-α) (10 ng/mL) alone weakly induced RANKL expression in this sample. However, when CXCL10 was added to TNF-α, RANKL expression increased. Interleukin-1-beta (IL-1β) (10 ng/mL) alone induced RANKL gene expression, and band intensity did not change when CXCL10 was added. CXCL10, interferon-gamma-inducible protein 10; GAPDH, glyceraldehyde-3-phosphate dehydrogenase.