title: Inhibiting receptor tyrosine kinase AXL with small molecule inhibitor BMS-777607 reduces glioblastoma growth, migration, and invasion in vitro and in vivo.
abstract: OBJECTIVE
  Receptor tyrosine kinase AXL (RTK-AXL) is regarded as suitable target in glioma therapy. Here we evaluate the anti-tumoral effect of small molecule inhibitor BMS-777607 targeting RTK-AXL in a preclinical glioma model and provide evidence that RTK-AXL is expressed and phosphorylated in primary and recurrent glioblastoma multiforme (GBM).
  
  
  METHODS
  We studied the impact of BMS-777607 targeting RTK-AXL in GBM models in vitro and in vivo utilizing glioma cells SF126 and U118MG. Impact on proliferation, apoptosis and angiogenesis was investigated by immunohistochemistry (IHC) and functional assays in vitro and in vivo. Tumor growth was assessed with MRI. Human GBM tissue was analyzed in terms of RTK-AXL phosphorylation by immunoprecipitation and immunohistochemistry.
  
  
  RESULTS
  BMS-777607 displayed various anti-cancer effects dependent on increased apoptosis, decreased proliferation and migration in vitro and ex vivo in SF126 and U118 GBM cells. In vivo we observed a 56% tumor volume reduction in SF126 xenografts and remission in U118MG xenografts of more than 91%. The tube formation assay confirmed the anti-angiogenic effect of BMS-777607, which became also apparent in tumor xenografts. IHC of human GBM tissue localized phosphorylated RTK-AXL in hypercellular tumor regions, the migratory front of tumor cells in pseudo-palisades, and in vascular proliferates within the tumor. We further proved RTK-AXL phosphorylation in primary and recurrent disease state.
  
  
  CONCLUSIONS
  Collectively, these data strongly suggest that targeting RTK-AXL with BMS-777607 could represent a novel and potent regimen for the treatment of primary and recurrent GBM.
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Julia
authors: J
authors: Onken
authors: Department of Molecular Biology, Max-Planck Institute of Biochemistry, Martinsried, Germany.
authors: Robert
authors: R
authors: Torka
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Sören
authors: S
authors: Korsing
authors: Institute of Neuropathology, Charité, Berlin, Germany.
authors: Josefine
authors: J
authors: Radke
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Irina
authors: I
authors: Krementeskaia
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Melina
authors: M
authors: Nieminen
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Xi
authors: X
authors: Bai
authors: Department of Molecular Biology, Max-Planck Institute of Biochemistry, Martinsried, Germany.
authors: Axel
authors: A
authors: Ullrich
authors: Institute of Neuropathology, Charité, Berlin, Germany.
authors: Frank
authors: F
authors: Heppner
authors: Department of Neurosurgery, Charité, Berlin, Germany.
authors: Peter
authors: P
authors: Vajkoczy
mesh_terms: D000631:Aminopyridines / Q000494:pharmacology*; D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D005909:Glioblastoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009361:Neoplasm Invasiveness; D010766:Phosphorylation / Q000187:drug effects; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011728:Pyridones / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays; D000094963:Axl Receptor Tyrosine Kinase
chemical_list: D000631:Aminopyridines; D020533:Angiogenesis Inhibitors; C550356:N-(4-(2-amino-3-chloropyridin-4-yloxy)-3-fluorophenyl)-4-ethoxy-1-(4-fluorophenyl)-2-oxo-1,2-dihydropyridine-3-carboxamide; D011518:Proto-Oncogene Proteins; D011728:Pyridones; D020794:Receptor Protein-Tyrosine Kinases; D000094963:Axl Receptor Tyrosine Kinase
keywords: glioblastoma multiforme (GBM); invasion; receptor tyrosine kinase AXL (RTK-AXL); small molecule inhibitor BMS-777607; xenograft model