TAT-ANK is a peptide derived from amino acid residues 179-191 of the G-protein coupled receptor kinase interacting protein-1 (GIT1) ankyrin domain, which are are crucial for GIT1 binding to the Notch transcription repressor RBP-J. In vitro, application of TAT-ANK significantly inhibits Delta-like 4 (Dll4) expression and Notch 1 activation in human umbilical vein endothelial cells (HUVECs) by competing with activated Notch1 binding to RBP-J, and in mouse models, TAT-ANK reduces tumour size through impairing tumour angiogenesis.
