MAPK3 and cancer: In cells stimulated by extracellular CypA, pathways like extracellular signal-regulated kinase 1 and 2 (ERK1/2), nuclear factor kappa-B (NF-κB), protein kinase B (AKT), Jun N terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) become activated.47–50 Recent studies highlight CypA’s overexpression in several cancer types, including gastric, breast, colorectal, liver, lung, and melanoma.