MAPK8 and cancer: By using a phosphokinase assay, we were able to identify potential new substrates GSK-3α/β, GSK-3β, Src, STAT5a/b, WNK1, PRAS40, RSK1/2, β-catenin, c-Jun and HSP60 known as drivers of cancer, whose relevant residues could be dephosphorylated by DUSP8 in addition to the reported DUSP8 relevant residues of JNK and p38 [21, 22].