Dipeptidyl peptidase-IV (DPP-IV) is an enzyme that deactivates incretin hormones such as glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), which are crucial in regulating blood glucose levels. Additionally, DPP-IV functions as a binding protein and ligand for various extracellular molecules. This enzyme is instrumental in research related to diabetes and cancer.