title: The Notch signaling pathway is related to neurovascular progression of pancreatic cancer.
abstract: OBJECTIVE
  To analyze the potential role of the Notch signaling pathway in pancreatic cancer angiogenesis and invasion.
  
  
  BACKGROUND
  Angiogenesis, pain, and early neuroinvasion are clinical features of pancreatic cancer. Blood vessels and nerves develop together and use common routes through the organism. The Notch pathway (Notch-1/4, Jagged-1/2, Delta-1) appears crucial in this process. The current study analyzed the Notch pathway in pancreatic cancer and characterized its angiogenic and invasive effects.
  
  
  METHODS
  Five PaCa cell lines were cultured for the in vitro experiments. Real-time quantitative RT-PCR was done to quantify mRNA expression in 31 human PaCa specimens, and immunohistochemistry was used to localize protein expression within tumor specimens. Activation of the Notch signaling was done by transfection of PaCa cells with a constitutive active Notch-1 mutant (Notch-IC). Overexpression of Jagged and Delta was achieved by transfection of full-length cDNA. Spheroid assays were used to study angiogenesis and ELISAs to measure VEGF, bFGF, and angiogenin expression. Matrigel invasion assays were used to analyze tumor cell invasion.
  
  
  RESULTS
  Notch-3 and Notch-4 mRNA were significantly (P < 0.001) overexpressed in PaCa. Immunohistochemistry revealed protein accumulation of Notch-1 as well. All ligands were significantly up-regulated. A positive immunosignal of ligands was seen in nerves, blood vessels, and ductal tumor cells. Transfection of PaCa cells with the constitutive active Notch-IC mutant and with Jagged-1 revealed increased levels for VEGF. Concomitantly, recombinant Jagged-1 increased sprouting of endothelial cells in the spheroid assay.
  
  
  CONCLUSIONS
  The Notch pathway most likely regulates neurovascular development in pancreatic cancer. Activation of this signaling pathway by constitutive Notch-1 mutants and by Jagged-1 causes an angiogenic and invasive tumor phenotype. Specific blockade of Notch signaling may therefore be beneficial for patients with pancreatic cancer.
authors.affiliation: Department of General Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Büchler
authors.forename: Amiq
authors.initials: A
authors.lastname: Gazdhar
authors.forename: Mario
authors.initials: M
authors.lastname: Schubert
authors.forename: Nathalia
authors.initials: N
authors.lastname: Giese
authors.forename: Howard A
authors.initials: HA
authors.lastname: Reber
authors.forename: Oscar J
authors.initials: OJ
authors.lastname: Hines
authors.forename: Thomas
authors.initials: T
authors.lastname: Giese
authors.forename: Güralp O
authors.initials: GO
authors.lastname: Ceyhan
authors.forename: Michael
authors.initials: M
authors.lastname: Müller
authors.forename: Markus W
authors.initials: MW
authors.lastname: Büchler
authors.forename: Helmut
authors.initials: H
authors.lastname: Friess
mesh_terms: D018450:Disease Progression; D005260:Female; D015870:Gene Expression; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D009389:Neovascularization, Pathologic; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger