title: Double Methotrexate-Modified Neuropeptide Y Analogues Express Increased Toxicity and Overcome Drug Resistance in Breast Cancer Cells.
abstract: Bioconjugates containing the neuropeptide Y (NPY) analogue [F(7),P(34)]-NPY as targeting moiety are able to deliver toxic agents specifically to breast cancer cells that overexpress the human Y1-receptor (hY1R). To increase their activity, multiple toxophores can be attached to one peptide. Herein, synthesis and characterization of [F(7),P(34)]-NPY conjugates containing two methotrexate (MTX) molecules are presented. First, carboxytetramethylrhodamine was linked to [F(7),P(34)]-NPY by amide or enzymatic linkage. The conjugate containing the enzymatic cleavage site showed high extracellular stability and fast intracellular release. Then, MTX was introduced at positions four and 22 of [F(7),P(34)]-NPY, connected by enzymatic or amide linkage. The toxicity of the analogues on breast cancer cells was hY1R-mediated and dependent on the used linkage and amount of toxophores. Furthermore, conjugates revealed higher potency than MTX on MTX-resistant cells. These results emphasize that peptide-drug conjugates can overcome drug resistance and that the attachment of multiple cleavable toxophores enhances the efficiency of this smart delivery system.
authors.affiliation: Universität Leipzig, Institute of Biochemistry , Brüderstraße 34, 04103 Leipzig, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Böhme
authors.affiliation: Universität Leipzig, Institute of Biochemistry , Brüderstraße 34, 04103 Leipzig, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Krieghoff
authors.affiliation: Universität Leipzig, Institute of Biochemistry , Brüderstraße 34, 04103 Leipzig, Germany.
authors.forename: Annette G
authors.initials: AG
authors.lastname: Beck-Sickinger
mesh_terms: D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology*; D002470:Cell Survival / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D005260:Female; D006801:Humans; D008727:Methotrexate / Q000737:chemistry*; D008969:Molecular Sequence Data; D009478:Neuropeptide Y / Q000737:chemistry*; D017476:Receptors, Neuropeptide Y / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; D008727:Methotrexate