Four individually druggable MET hotspots mediate HGF-driven tumor progression

J Clin Invest. 2014 Jul;124(7):3172-86. doi: 10.1172/JCI72316. Epub 2014 May 27.

Abstract

Activation of MET by HGF plays a key role in tumor progression. Using a recently developed llama platform that generates human-like immunoglobulins, we selected 68 different antibodies that compete with HGF for binding to MET. HGF-competing antibodies recognized 4 distinct hotspots localized in different MET domains. We identified 1 hotspot that coincides with the known HGF β chain binding site on blades 2-3 of the SEMA domain β-propeller. We determined that a second and a third hotspot lie within blade 5 of the SEMA domain and IPT domains 2-3, both of which are thought to bind to HGF α chain. Characterization of the fourth hotspot revealed a region across the PSI-IPT 1 domains not previously associated with HGF binding. Individual or combined targeting of these hotspots effectively interrupted HGF/MET signaling in multiple cell-based biochemical and biological assays. Selected antibodies directed against SEMA blades 2-3 and the PSI-IPT 1 region inhibited brain invasion and prolonged survival in a glioblastoma multiforme model, prevented metastatic disease following neoadjuvant therapy in a triple-negative mammary carcinoma model, and suppressed cancer cell dissemination to the liver in a KRAS-mutant metastatic colorectal cancer model. These results identify multiple regions of MET responsible for HGF-mediated tumor progression, unraveling the complexity of HGF-MET interaction, and provide selective molecular tools for targeting MET activity in cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal
  • Antibody Affinity
  • Binding Sites
  • Binding, Competitive
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / metabolism*
  • Brain Neoplasms / pathology
  • Camelids, New World
  • Cell Line, Tumor
  • Disease Models, Animal
  • Disease Progression
  • Glioblastoma / genetics*
  • Glioblastoma / metabolism*
  • Glioblastoma / pathology
  • Hepatocyte Growth Factor / chemistry
  • Hepatocyte Growth Factor / immunology
  • Hepatocyte Growth Factor / metabolism*
  • Humans
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • Models, Molecular
  • Protein Interaction Domains and Motifs
  • Proto-Oncogene Proteins c-met / chemistry
  • Proto-Oncogene Proteins c-met / genetics*
  • Proto-Oncogene Proteins c-met / metabolism*

Substances

  • Antibodies, Monoclonal
  • HGF protein, human
  • HGF protein, mouse
  • Hepatocyte Growth Factor
  • Proto-Oncogene Proteins c-met