The LXR agonist T0901317 blocks IL-1β– and IL-6–induced FLS invasion. Treatment of DA FLS with IL-1β (10 ng/mL) or IL-6 (10 ng/mL) significantly increased cell invasion by 154% and 179%, respectively, compared with controls (white bar). Treatment with T0901317 (1 μmol/L) prevented the cytokine-induced increased invasion, suggesting that LXR interferes with IL-1β and IL-6 activity. T0901317 treatment reduced FLS invasion to levels below the control group, suggesting that factors other than IL-1β, IL-6 and their receptors are involved in the LXR-mediated suppression of invasion (#P = 0.022; *P = 0.017; mean ± standard error of the mean; t test; n = 5 different FLS cell lines).