KLF4 has only rarely been mentioned to be related to inflammatory diseases, but is known as a regulator of proinflammatory cytokine expression in rheumatoid arthritis (51), and is one of the susceptibility genes for psoriasis (52, 53), 2 diseases in which IL-36γ is significantly increased in the inflamed tissues (54–57). Here, KLF4 is linked to rheumatoid arthritis.