Inhibition of PTPN2 by PTP inhibitor V

摘要

Protein phosphorylation is closely linked to critical pathways in numerous human diseases, which is regulated by the coordinated activities of kinases and phosphatases. Protein phosphorylation occurs predominantly on serine, threonine, and tyrosine residues of proteins and plays important roles in the regulation of physiological processes including gene expression, proliferation, differentiation, cell cycle arrest, and apoptosis.2 About 30% of proteins are phosphorylated in the mammalian cell. In case of eukaryotic cells, tyrosine phosphorylation occupies only 0.01-0.05% of total protein phosphorylation, while most of protein phosphorylation occurs on serine or threonine residues. However, growth factor stimulation or tumorigenesis enhances the level of tyrosine phosphorylation up to 1-2% of total protein phosphorylation. Protein phosphorylation is a reversible process that is controlled by protein kinases and protein phosphatases. In particular, protein tyrosine phosphatases (PTPs) are involved in most signaling pathways and thus play important roles in eukaryotes.4 PTPs superfamily comprises