MAPK14 and rheumatoid arthritis: Our study focused on the phosphorylated p38 MAP kinase since the phosphorylation of p38 MAP kinase leads to transcription initiation by binding to regulatory sites on DNA, in turn, leads to the activation of pro-inflammatory cytokines such as TNF-α and IL-1, which play a central role in the pathogenesis of RA (Kim et al. 2010).