RA-FLS seeded in 96-well plates (5,000 cells/well) were pre-treated with RLE (0–600 μg/mL) or 100 μM of indomethacin (positive control) for 1 h and then treated with IL-6/sIL-6R for 24 or 48 h. Here, IL6 is linked to rheumatoid arthritis.