title: Coexpression of erythropoietin and vascular endothelial growth factor in nervous system tumors associated with von Hippel-Lindau tumor suppressor gene loss of function.
abstract: Hemangioblastomas are highly vascular tumors of the central nervous system that overexpress the hypoxia-inducible gene, vascular endothelial growth factor (VEGF), as a consequence of mutational inactivation of the von Hippel-Lindau tumor suppressor gene (VHL). Previous reports showed that hemangioblastomas can also express erythropoietin (Epo), which is also hypoxia-inducible. However, Epo expression in hemangioblastomas was observed only in individual cases, and the analyses were mainly based on indirect determination of erythropoiesis-stimulating activity. Therefore, we analyzed a series of 11 hemangioblastomas for Epo, VEGF, and VHL expression by Northern blot analysis and compared the results with normal brain and glioblastomas. Surprisingly, we observed Epo mRNA expression in all hemangioblastoma specimens analyzed, but in none of four glioblastomas. In contrast, VEGF mRNA was expressed in all hemangioblastomas and all glioblastomas. In situ hybridization revealed neoplastic stromal cells as Epo- and VEGF-producing cells in hemangioblastomas. These results suggest that in the nonhypoxic microenvironment of hemangioblastoma, Epo, similar to VEGF, might be negatively regulated by the VHL gene product.
authors.affiliation: Department of Neuropathology, Freiburg University Medical School, Freiburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Krieg
authors.forename: H H
authors.initials: HH
authors.lastname: Marti
authors.forename: K H
authors.initials: KH
authors.lastname: Plate
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000378:metabolism; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D015687:Cell Hypoxia; D016543:Central Nervous System Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016228:Endothelial Growth Factors / Q000096:biosynthesis* / Q000235:genetics; D004920:Erythropoiesis; D004921:Erythropoietin / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D016147:Genes, Tumor Suppressor; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018325:Hemangioblastoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D006729:Hormones, Ectopic / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D017403:In Situ Hybridization; D008025:Ligases; D008222:Lymphokines / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D017154:Stromal Cells / Q000378:metabolism; D025521:Tumor Suppressor Proteins; D044767:Ubiquitin-Protein Ligases; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D006623:von Hippel-Lindau Disease / Q000235:genetics*
chemical_list: D016228:Endothelial Growth Factors; D006729:Hormones, Ectopic; D008222:Lymphokines; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011506:Proteins; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D004921:Erythropoietin; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D008025:Ligases; C497446:VHL protein, human