MAPK3 and cancer: EGFR, JAK tyrosine kinase, Src tyrosine kinase and Erk1/2 play a dominant role in STAT3 phosphorylation and are linked with cancer cell proliferation, metabolic regulation and metastasis (Chung et al, 1997; Garcia et al, 2001; Silva, 2004; Yue et al, 2012; Gough et al, 2013).