STAT1 and breast carcinoma: In melanoma, cervical, and pancreatic carcinoma cells, PTPN13 has been implicated as an oncogene that acts by inhibiting Fas-mediated apoptosis.27,44–48 By contrast, PTPN13 has been shown to function as a tumor suppressor by stabilizing cell–cell junctions and inhibiting cell invasion in breast cancer,49 as well as by regulating IGF2BP1 and c-Myc expression in hepatocellular carcinoma.50 However, in our study, APC11 did not activate apoptotic pathways in CRC cells, suggesting that the APC/PTPN13/STAT1 axis is distinct from Fas-mediated apoptotic pathways.