Consistent with the results from a previous study [18], treatment with IL-1β (10 ng/mL) to SW982 cells for 72 h markedly increased cell viability and proliferation, thus confirming that synovial fibroblasts, like SW982 cells, could indeed proliferate after IL-1β exposure and might play a role in the pathogenesis of RA. This evidence concerns the gene IL1B and rheumatoid arthritis.