title: Endothelial cell barrier impairment induced by glioblastomas and transforming growth factor beta2 involves matrix metalloproteinases and tight junction proteins.
abstract: Gliomas, particularly glioblastoma multiforme, perturb the blood-brain barrier and cause brain edema that contributes to morbidity and mortality. The mechanisms underlying this vasogenic edema are poorly understood. We examined the effects of cocultured primary cultured human glioblastoma cells and glioma-derived growth factors on the endothelial cell tight junction proteins claudin 1, claudin 5, occludin, and zonula occludens 1 of brain-derived microvascular endothelial cells and a human umbilical vein endothelial cell line. Cocultured glioblastoma cells and glioma-derived factors (e.g. transforming growth factor beta2) enhanced the paracellular flux of endothelial cell monolayers in conjunction with downregulation of the tight junction proteins. Neutralizing anti-transforming growth factor beta2 antibodies partially restored the barrier properties in this in vitro blood-brain barrier model. The involvement of endothelial cell-derived matrix metalloproteinases (MMPs) was demonstrated by quantitative reverse-transcriptase-polymerase chain reaction analysis and by the determination of MMP activities via zymography and fluorometry in the presence or absence of the MMP inhibitor GM6001. Occludin, claudin 1, and claudin 5 were expressed in microvascular endothelial cells in nonneoplastic brain samples but were significantly reduced in anaplastic astrocytoma and glioblastoma samples. Taken together, these in vitro and in vivo results indicate that glioma-derived factors may induce MMPs and downregulate endothelial tight junction protein and, thus, play a key role in glioma-induced impairment of the blood-brain barrier.
authors.affiliation: Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ishihara
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kubota
authors.forename: Raija L P
authors.initials: RL
authors.lastname: Lindberg
authors.forename: David
authors.initials: D
authors.lastname: Leppert
authors.forename: Sergio M
authors.initials: SM
authors.lastname: Gloor
authors.forename: Mariella
authors.initials: M
authors.lastname: Errede
authors.forename: Daniela
authors.initials: D
authors.lastname: Virgintino
authors.forename: Adriano
authors.initials: A
authors.lastname: Fontana
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yonekawa
authors.forename: Karl
authors.initials: K
authors.lastname: Frei
mesh_terms: D001812:Blood-Brain Barrier / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D001921:Brain / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology; D001929:Brain Edema / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D002478:Cells, Cultured; D002536:Cerebral Arteries / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D062445:Claudin-1; D062507:Claudin-5; D018920:Coculture Techniques; D015536:Down-Regulation / Q000502:physiology; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism / Q000473:pathology; D005909:Glioblastoma / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007231:Infant, Newborn; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D062793:Occludin; D019108:Tight Junctions / Q000378:metabolism* / Q000473:pathology; D053781:Transforming Growth Factor beta2 / Q000378:metabolism* / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: C568108:CLDN1 protein, human; C107466:CLDN5 protein, human; D062445:Claudin-1; D062507:Claudin-5; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; D053781:Transforming Growth Factor beta2; D020782:Matrix Metalloproteinases