PP1

PP1 is a selective and potent Src-family tyrosine kinase inhibitor. PP1 studies have proved its ability to potently inhibit Lck and Fyn (FynT), IL-2 gene activation in T lymphocytes, and anti-CD3-induced protein tyrosine phosphorylation. Research indicates that PP1 effectively blocks LPA and EGF-enhanced tyrosine phosphorylation, MAPK activation downstream of EGFR, Rsk-1 (p90RSK) activation by H2O2, Kit and Bcr-Abl tyrosine kinases, and degrades RETMEN2A and RETMEN2B oncoproteins via proteosomal targeting. PP1 and its analog, PP2, are powerful inhibitors of TGF-β-induced cell migration and invasion in-vitro. PP1 inhibits anti-CD3-induced T cell tyrosine phosphorylation, TcR-induced T cell proliferation, and IL-2 gene induction. PP1 has been demonstrated to reduce the expression of vascular endothelial growth factor (VEGF), protect the blood-brain barrier, reduce brain edema immediately after subarachnoid hemorrhage, and offer cerebral protection against stroke. It prevents metastatic spread in late-stage pancreatic ductal adenocarcinoma and non-small cell lung cancer.