To evaluate the effect of SR9009 on proinflammatory cytokines, we measured the mRNA levels of IL-6, IL-8, COX-2, iNOS, chemokine (C-C motif) ligand 2 (CCL2), and C-X-C motif chemokine ligand 10 (CXCL10) in IL-1β-stimulated RA FLSs by real-time PCR. Here, CXCL8 is linked to rheumatoid arthritis.