PTPN23 and breast cancer: PTPN23 participates in physiological and biochemical processes including (1) inhibition of the pathogenesis of breast cancer and hepatocellular carcinoma (HCC) (18, 34) where PTPN23 inhibits endothelial cell migration through dephosphorylation of focal adhesion kinase (FAK) and interaction with Src kinases (9, 10).