MAPK3 and cancer: Arginine feeding to hungry mice promotes ERK1/2 activation and macrophage production of TNF-α [62].The resulting TNF-α researchers found that in the co-culture model of GC cells and cancer-associated fibroblasts (CAFs), GC cells release pro-inflammatory cytokine TNF-α through the TNFR2-NF-κB-IRF-1 pathway, which can induce CAFs to secrete IL-33, IL-33 derived from CAFs activates the ERK1/2-SP1-ZEB2 pathway in a st21-dependent manner to induce EMT, thereby enhancing the migration and invasion of GC [68].