Project description:Glioblastoma multiforme (GBM) is the most common and aggressive type of primary brain tumor. Epidermal growth-factor (EGF) and platelet-derived growth-factor (PDGF) receptors are frequently amplified and/or possess gain-of-function mutations in these tumors. Despite years of research into tyrosine-kinase inhibitors, clinical trials have shown disappointing efficacy. One of the underlying reasons is intra-tumor heterogeneity. To assess the effect of intra-tumor heterogeneity on gene expression, we derived a general approach to map single-cell expression profiles to sequentially-acquired mutations identified from exome sequencing. Using 288 single cells, we constructed high-resolution phylogenies of EGF-driven and PDGF-driven GBMs, modeling transcriptional kinetics during tumor evolution. A deletion in a PDGF-receptor domain involved in dimerization correlated to an up-regulation of the PI3K/AKT pathway in a proneural GBM, and ectopic expression of this mutant PDGFRA in vitro enhanced proliferation and invasiveness. Descending the phylogenetic tree of the PDGFR-driven tumor corresponded to a progressive induction of an oligodendrocyte progenitor-like cell type that expresses growth and angiogenic factors. In contrast, phylogenetic analysis of an EGFR-amplified tumor showed a gradual up-regulation of pro-invasive genes.
Project description:Overall study: Identification of PDGF-dependent patterns of gene expression in U87 glioblastoma cells. RNA was obtained from triplicate dishes of 5 different groups of U87 cells, each (total 15) analyzed with one U95 microarray chip. Three different comparisons were made: 1) Clone 3.1 (34580-34582) vs. clone 3.3 (34583-34585) vs. parent U87 (34592-34594). Purpose: demonstrate that the gene expression profiles between these 3 cell lines are not different, so they could be pooled as a single untreated group. 2) Pooled control group (34580-34585, 34592-34594) vs. clone 8.1 (34586-34588). Purpose: identify genes specifically controlled by autocrine PDGF activity. 3) Clone 8.1 (34586-34588) vs. clone 8.1 treated with PDGF (34589-34591) Purpose: Identify genes specifically induced by exogenous PDGF. Keywords = platelet-derived growth factor Keywords = glioblastoma Keywords = brain cancer Keywords = sterol regulatory element binding protein Keywords = SREBP Keywords: ordered
Project description:Identification of critical survival determinants of PDGF-driven proneural glioma. Results provided information about the genes and pathways that are regulated by PDGF signaling in PDGF-driven proneural glioma and led to the assessment of the importance of the USP1-ID2 axis in proneural glioma. Total RNA was obtained from untreated and Dox treated PDGF-driven glioma spheroid cells (PDGF-GSC) which had been isolated from the Gfap-tTa/Tre-PDGFB mouse model used in our study. The data were analyzed to determine the genes that are regulated by PDGF signaling in PDGF-driven glioma.
Project description:Identification of critical survival determinants of PDGF-driven proneural glioma. Results provided information about the genes and pathways that are regulated by PDGF signaling in PDGF-driven proneural glioma and led to the assessment of the importance of the USP1-ID2 axis in proneural glioma. Total RNA obtained from PDGF-driven glioma spheroid cells (PDGF-GSC) and primary tumors arising in the Gfap-tTa/Tre-PDGFB mouse model used in our study was analyzed to determine to which subtype of GBM these specimens belonged.
Project description:The trascription profiles of PDGF-B and EGFRvIII induced glioma models were compared. We show that both models converge towards a phenotype that resembles proneural glioblastoma subset.
Project description:Identification of critical survival determinants of PDGF-driven proneural glioma. Results provided information about the genes and pathways that are regulated by PDGF signaling in PDGF-driven proneural glioma and led to the assessment of the importance of the USP1-ID2 axis in proneural glioma.
Project description:Identification of critical survival determinants of PDGF-driven proneural glioma. Results provided information about the genes and pathways that are regulated by PDGF signaling in PDGF-driven proneural glioma and led to the assessment of the importance of the USP1-ID2 axis in proneural glioma.
Project description:Overall study: Identification of PDGF-dependent patterns of gene expression in U87 glioblastoma cells. RNA was obtained from triplicate dishes of 5 different groups of U87 cells, each (total 15) analyzed with one U95 microarray chip.,Three different comparisons were made:,1) Clone 3.1 (34580-34582) vs. clone 3.3 (34583-34585) vs. parent U87 (34592-34594).,Purpose: demonstrate that the gene expression profiles between these 3 cell lines are not different, so they could be pooled as a single untreated group.,2) Pooled control group (34580-34585, 34592-34594) vs. clone 8.1 (34586-34588).,Purpose: identify genes specifically controlled by autocrine PDGF activity.,3) Clone 8.1 (34586-34588),vs. clone 8.1 treated with PDGF (34589-34591),Purpose: Identify genes specifically induced by exogenous PDGF.
