PTPN11 and cancer: Src homology 2-containing protein tyrosine phosphatase 2 (SHP2) is a non-receptor protein tyrosine phosphatase (PTP) encoded by PTPN11 gene.259 As protein tyrosine phosphorylation plays an essential role in multiple intracellular processes, SHP2 is involved in the regulation of multiple signaling pathways, including those involved in cancer cells, such as RAS-MAPK, PI3K-AKT and JAK-STAT pathways.