Compared with control cells, LKB1-suppressed RA FLSs displayed increased levels of mitochondria-specific ROS (by 70.8% compared to control siRNA, p < 0.05) and Fe2+ (by 60.4% compared to control siRNA, p < 0.01) (Figure 2B,C) and a decreased level of the antioxidant GSH (Figure 2D). Here, STK11 is linked to rheumatoid arthritis.