Project description:We have developed a nonheuristic genome topography scan (GTS) algorithm to characterize the patterns of genomic alterations in human glioblastoma (GBM), identifying frequent p18INK4C and p16INK4A codeletion. Functional reconstitution of p18INK4C in GBM cells null for both p16INK4A and p18INK4C resulted in impaired cell-cycle progression and tumorigenic potential. Conversely, RNAi-mediated depletion of p18INK4C in p16INK4A-deficient primary astrocytes or established GBM cells enhanced tumorigenicity in vitro and in vivo. Furthermore, acute suppression of p16INK4A in primary astrocytes induced a concomitant increase in p18INK4C. Together, these findings uncover a feedback regulatory circuit in the astrocytic lineage and demonstrate a bona fide tumor suppressor role for p18INK4C in human GBM wherein it functions cooperatively with other INK4 family members to constrain inappropriate proliferation. Keywords: comparative genomic hybridization DNA copy number abberation of human glioblastoma tumors were obtained by comparative genomic hybridization of GBM tumor vs. normal human DNA. 11 human GBM samples were analyzed on Agilent human 244A human cgh array (G4411B). Normal Human DNA was used as reference. Some samples were hybridized with dye-swap replica.

2008-04-29 | E-GEOD-9177 | biostudies-arrayexpress

Single cell data from IDH mutant astroxytoma and IDH wildtype GBM tumor specimen

Project description:Glioblastoma (GBM) is the most common and aggressive primary brain malignancy. Adhesion G protein-coupled receptors (aGPCRs) have attracted interest for their functional role in gliomagenesis and their potential as treatment targets. To identify therapeutically targetable opportunities among aGPCR family members in an unbiased fashion, we analyzed expression levels of all aGPCRs in GBM and non-neoplastic brain tissue. Using bulk and single cell transcriptomic and proteomic data, we show that CD97 (ADGRE5), an aGPCR previously implicated in GBM pathogenesis, is the most promising aGPCR target in GBM, by virtue of its abundance in all GBM tumors and its de novo expression profile in GBM compared to normal brain tissue and neural progenitors. CD97 knockdown or knockout significantly reduces the tumor initiation capacity of patient-derived GBM cells (PDGC) in vitro and in vivo. Transcriptomic and metabolomic data from PDGCs suggest that CD97 promotes glycolytic metabolism. The oncogenic and metabolic effects of CD97 are mediated by the MAPK pathway. Activation of MAPK signaling depends on phosphorylation of the cytosolic C-terminus of CD97 and recruitment of -arrestin. Using single-cell RNA-sequencing and biochemical assays, we demonstrate that THY1/CD90 is the most likely CD97 ligand in GBM. Lastly, we show that targeting of GBM cells with an anti-CD97 antibody-drug conjugate in vitro selectively kills tumor cells but not human astrocytes or neural stem cells. Our studies identify CD97 as an important regulator of tumor metabolism in GBM, elucidate mechanisms of receptor activation and signaling, and provide strong scientific rationale for developing biologics to target CD97 in GBM.

2023-12-01 | GSE230389 | GEO

Single RNA-Seq on GBM cells from NPCTKO mouse models

Project description:Glioblastoma multiforme (GBM), a highly malignant and heterogeneous brain tumor, contains various types of tumor and non-tumor cells. Whether GBM cells can trans-differentiate into non-neural cell types, including mural cells or endothelial cells, to support tumor growth and invasion remains controversial. Here we generated two genetic GBM models de novo in immunocompetent mouse brains, mimicking essential pathological and molecular features of human GBMs. Single-cell RNA sequencing showed that patterns of copy-number variations (CNVs) of mural cells and endothelial cells were distinct from those of GBM cells, indicating discrete origins of GBM cells and vascular components. Furthermore, lineage tracing and transplantation studies demonstrated that, although blood vessels in GBM brains underwent drastic remodeling, GBM cells did not give rise to non-neural cell types in the brain. Intriguingly, GBM cells could randomly express mesenchymal markers, including those for mural cells, during gliomagenesis. Most importantly, single-cell CNV analysis of human GBM specimens also strongly suggested that GBM cells and vascular cells are separate lineages. Instead, non-neural cell types expanded by proliferation during tumorigenesis. Therefore, cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis. Our findings advance understanding of cell lineage dynamics during gliomagenesis, and have implications for targeted treatment of GBMs.

2022-07-07 | GSE190154 | GEO

Bulk RNA-Seq on GBM cells from NPCTKO and NSCHRas-shp53 mouse models

2022-07-07 | GSE189541 | GEO

Tumor progression is independent of tumor associated macrophages in two lineage-based mouse models of GBM [TAMdepletedVsControl RNAseq]

Project description:We investigate the transcriptomic changes resulting from TAM depletion in Type 1 and Type 2 GBMs We perform bulk RNAseq on TAM depleted and Control Type 1 and Type 2 GBM bulk tumor tissue

2023-03-06 | GSE226050 | GEO

RNA sequencing of blood-brain barrier (BBB) microvessels from mice with orthotopic GBM showing the benefit of triple therapy combining anti-immune checkpoint therapy with dual-anti angiogenic therapy.

Project description:Glioblastoma multiforme (GBM) is a non T cell-inflamed cancer characterized by an immunosuppressive microenvironment that impedes dendritic cell maturation and T cell cytotoxicity. The alleviation of immunosuppression might be a prerequisite for succesful immune checkpoint therapy in GBM. We here combine anti-angiogenic and immune checkpoint therapy and demonstrate improved therapeutic efficacy in syngeneic, orthotopic GBM models. We observed that blockade of vascular endothelial growth factor (VEGF), Angiopoietin-2 (Ang-2) and programmed cell death protein-1 (PD-1) significantly extended survival compared to vascular targeting alone. In the GBM microenvironment, triple therapy increased the numbers of cytotoxic T-lymphocytes that inversely correlated with myeloid-derived suppressor and regulatory T cells. Furthermore, transcriptomic analysis of GBM microvessels indicates a global vascular normalization that was highest after triple therapy. Our results propose a rationale to overcome limitations of VEGF monotherapy by integrating the synergistic effects of VEGF/Ang-2 and PD-1 blockade to reinforce anti-tumor immunity through a normalized vasculature.

2021-03-01 | GSE130324 | GEO

Human GBM tumor vs Normal Human DNA

2008-04-29 | GSE9177 | GEO