title: Blockage of VEGF-induced angiogenesis by preventing VEGF secretion.
abstract: Vascular endothelial growth factor (VEGF)/vascular permeability factor is one of the most frequently expressed angiogenic factors in several pathological tissues. Development of VEGF antagonists has become an important approach in the treatment of angiogenesis-dependent diseases. Here we describe a novel anti-VEGF strategy by preventing the secretion of VEGF. We utilize the fact that placenta growth factor (PlGF)-1, a member of the VEGF family lacking detectable angiogenic activity, preferentially forms intracellular heterodimers with VEGF in cells coexpressing both factors. We constructed a retroviral vector containing human PlGF-1 or VEGF with a C-terminal KDEL sequence, which is a mammalian retention signal for the endoplasmic reticulum. Transduction of murine Lewis lung carcinoma cells with the retro-hPlGF-1-KDEL construct almost completely abrogated tumor growth. Consistent with the dramatic antitumor effect, most mouse VEGF molecules remained as intracellular mVEGF/hPlGF-1 heterodimers, and only a negligible amount of mVEGF homodimers were secreted. As a result, in hPlGF-1-KDEL-expressing tumors, blood vessels remained at very low numbers and lacked branching and capillary networks. Gene transfer of a hVEGF-KDEL construct into tumor cells likewise produced a dramatic antitumor effect. Thus, our study provides a novel antiangiogenic approach by preventing the secretion of VEGF.
authors.affiliation: Microbiology and Tumor Biology Center, Karolinska Institute, Stockholm, Sweden.
authors.forename: Meit
authors.initials: M
authors.lastname: Björndahl
authors.forename: Renhai
authors.initials: R
authors.lastname: Cao
authors.forename: Anna
authors.initials: A
authors.lastname: Eriksson
authors.forename: Yihai
authors.initials: Y
authors.lastname: Cao
mesh_terms: D020533:Angiogenesis Inhibitors / Q000235:genetics / Q000627:therapeutic use*; D000818:Animals; D017209:Apoptosis; D001681:Biological Assay; D018827:Carcinoma, Lewis Lung / Q000098:blood supply*; D002633:Chemotaxis / Q000187:drug effects; D019281:Dimerization; D004721:Endoplasmic Reticulum / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics / Q000627:therapeutic use; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000188:drug therapy*; D009842:Oligopeptides / Q000235:genetics; D000072483:Placenta Growth Factor; D011257:Pregnancy Proteins / Q000235:genetics / Q000502:physiology*; D021382:Protein Sorting Signals / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000502:physiology; D012190:Retroviridae / Q000235:genetics; D034421:Sus scrofa; D014161:Transduction, Genetic; D042461:Vascular Endothelial Growth Factor A / Q000737:chemistry / Q000378:metabolism*; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D009842:Oligopeptides; C000608036:PGF protein, human; C000608037:Pgf protein, mouse; D011257:Pregnancy Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C073762:lysyl-aspartyl-glutamyl-leucine; D000072483:Placenta Growth Factor; D040281:Vascular Endothelial Growth Factor Receptor-1; D040301:Vascular Endothelial Growth Factor Receptor-2