TNF and rheumatoid arthritis: Activated FLSs, in conjunction with TNF-α in the synovium, activate the NF-κB signaling pathways, inducing sustained expression of proinflammatory genes such as TNF-α, IL-6, IL-8, and IL-1β, thereby maintaining chronic inflammation and exacerbating the progression of RA (Pothacharoen et al., 2021; Xia et al., 2018).