ANPEP and neoplasm: For example, conjugating a cyclic NGR peptide that specifically binds to aminopeptidase N in the tumor vasculature with IFN-α [135], or constructing a fusion protein by coupling an antibody against CD20, which is highly expressed in B-cell lymphomas, with IFN-α [136], both can increase the concentration of IFN-α at the tumor site and enhance its antitumor activity.