title: Angiogenesis and expression of PDGF-C, VEGF, CD105 and HIF-1α in human glioblastoma.
abstract: Glioblastoma (GBM), the most frequent and aggressive brain tumor, is characterized by marked angiogenesis directly related to invasiveness and poor prognosis. Hypoxia is considered to be an important stimulus for angiogenesis by inducing hypoxia-inducible factor 1-alpha (HIF-1α) overexpression that activates platelet-derived growth factor (PDGF) and VEGF. The aim of this study is to analyze the expression of PDGF-C, VEGF in endothelial and tumor cells of GBM and their relation to HIF-1α expression. Two hundred and eight GBM cases were studied by tissue microarray immunohistochemical preparation. Expression of HIF-1α, VEGF and PDGF-C was observed in 184 (88.5%), 131 (63%) and 160 (76.9%) tumor cases, respectively. The numbers of vessels were quantified by CD34, PDGF-C, VEGF and CD105 staining, and were in median 20, 16, 5 and 6, respectively. The GBMs that showed positive or negative expression for HIF-1α showed a median vascular density of 30 and 14, respectively, for CD34 (P < 0.015). Positive expression for HIF-1α was correlated with VEGF and PDGF-C expression in tumors (P < 0.001). There was a significant correlation between VEGF and PDGF-C expression in the cytoplasm of GBM tumor cells (P < 0.0001). We showed that VEGF expression in tumor cells was correlated with its expression in blood vessels (P < 0.0001). Endothelial cells with PDGF-C and VEGF positive expression were also positive for CD105 and their nuclei for Ki-67, confirming the neoangiogenic and proliferative influence of VEGF and PDGF-C. VEGF nuclear staining in tumor cells (P = 0.002) as well as nuclear staining for HIF-1α and VEGF (P = 0.005) correlated with survival. In summary, our present findings of the concomitant upregulation of PDGF-C with VEGF in GBM tumor cells and vessels further reinforce the benefit of using combined anti-angiogenic approaches to potentially improve the therapeutic response for GBM.
authors.affiliation: Pio XII Foundation, Barretos Cancer Hospital, Sao Paulo, Brazil.
authors.forename: Carlos Afonso
authors.initials: CA
authors.lastname: Clara
authors.forename: Suely K N
authors.initials: SK
authors.lastname: Marie
authors.forename: José Reynaldo Walther
authors.initials: JR
authors.lastname: de Almeida
authors.forename: Alda
authors.initials: A
authors.lastname: Wakamatsu
authors.forename: Sueli Mieko
authors.initials: SM
authors.lastname: Oba-Shinjo
authors.forename: Miyuki
authors.initials: M
authors.lastname: Uno
authors.forename: Munro
authors.initials: M
authors.lastname: Neville
authors.forename: Sérgio
authors.initials: S
authors.lastname: Rosemberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D001932:Brain Neoplasms / Q000098:blood supply* / Q000378:metabolism* / Q000401:mortality; D000071063:Endoglin; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D005909:Glioblastoma / Q000098:blood supply* / Q000378:metabolism* / Q000401:mortality; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D008222:Lymphokines / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D010982:Platelet-Derived Growth Factor / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism; D016019:Survival Analysis; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D008222:Lymphokines; D010982:Platelet-Derived Growth Factor; D011956:Receptors, Cell Surface; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C411423:platelet-derived growth factor C
keywords: HIF-1α; PDGF-C; VEGF; angiogenesis; glioblastoma