Activation of certain signaling pathways in synovial macrophages, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), STAT3, and phosphoinositide 3-kinase (PI3K) signaling pathways, enhances the M1 phenotype and the inflammatory conditions of the RA synovium [24]. This evidence concerns the gene NFKB1 and rheumatoid arthritis.