Protein tyrosine phosphatase 1B dephosphorylates PITX1 and regulates p120RasGAP in hepatocellular carcinoma
Wei‐Tien Tai, Yao‐Li Chen, Pei‐Yi Chu, Li‐Ju Chen, Man‐Hsin Hung, Chung‐Wai Shiau, Jui‐Wen Huang, Ming‐Hsien Tsai, Kuen‐Feng Chen – 3 February 2016 – The effective therapeutic targets for hepatocellular carcinoma remain limited. Pituitary homeobox 1 (PITX1) functions as a tumor suppressor in hepatocarcinogenesis by regulating the expression level of Ras guanosine triphosphatase‐activating protein. Here, we report that protein tyrosine phosphatases 1B (PTP1B) directly dephosphorylated PITX1 at Y160, Y175, and Y179 to further weaken the protein stability of PITX.