TNF and rheumatoid arthritis: It is related to multiple factors and associated with chronic inflammation, such as oxidative stress and increased levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-1 [2], which are the major cytokines affecting the development and progression of inflammatory arthritis, including rheumatoid arthritis (RA) [3].