title: Aquaporin-4 upregulated expression in glioma tissue is a reaction to             glioma-associated edema induced by vascular endothelial growth factor.
abstract: Glioma-associated edema contributes significantly to morbidity and death in patients with glioma. It has been suggested that vascular endothelial growth factor (VEGF) and aquaporin-4 (AQP4) play important roles in glioma-associated edema. However, the effect of VEGF on AQP4 expression is not clear. In this study, AQP4 expression was assayed in cultured glioma cells that express different amounts of VEGF, and AQP4 expression, vessel permeability and water content were assayed in glioma xenografts that express different amounts of VEGF. No difference in AQP4 expression was found between glioma cells expressing different VEGF amounts in vitro. However, AQP4 expression was increased in glioma tissue with increased VEGF, vessel permeability and water content. In conclusion, VEGF does not directly affect AQP-4 expression. The redistribution of AQP4 in glioblastoma cells is a reaction to vasogenic edema induced by VEGF for the purpose of facilitating reabsorption of excess fluid. The pattern of AQP4 expression in glioma provides new insights into the molecular changes occurring in glioma-associated edema and may help plan future therapeutic strategies.
authors.affiliation: Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian 350005, PR China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Yang
authors.forename: Xingfu
authors.initials: X
authors.lastname: Wang
authors.forename: Shiming
authors.initials: S
authors.lastname: Zhen
authors.forename: Sheng
authors.initials: S
authors.lastname: Zhang
authors.forename: Dezhi
authors.initials: D
authors.lastname: Kang
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Lin
mesh_terms: D000818:Animals; D051401:Aquaporin 4 / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D001929:Brain Edema / Q000378:metabolism*; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D051381:Rats; D014183:Transplantation, Heterologous; D015854:Up-Regulation; D042442:Vascular Endothelial Growth Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: C496032:Aqp4 protein, rat; D051401:Aquaporin 4; D042442:Vascular Endothelial Growth Factors