Gene expression profiling of four subpopulations in GBM
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Viviane Tabar
PROVIDER: E-GEOD-24244 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:GBM is a heterogenous brain tumor with hyperproliferation of endothelial cells. In order to understand the cellular mechanism of vasculogenesis in GBM, four fractions of cells are seperated. Microarray assays was performed to examine the potential lineage relationship and the signal pathways involved in determining the cell identity and function.
2010-11-21 | GSE24244 | GEO
Project description:GBM is a heterogenous tumor. Based on membrane protein expression, the GBM single cell dissociates were seperated into different subfractions by FACS assay. The genomic aberration among each populations were compared by analysis of CGH data.
2010-11-21 | GSE24452 | GEO
Project description:GBM is a heterogenous tumor. Based on membrane protein expression, the GBM single cell dissociates were seperated into different subfractions by FACS assay. The genomic aberration among each populations were compared by analysis of CGH data. Genomic DNA were extracted from sorted cell population and CGH assay were performed to compare the similarity genomic abnormality among different cell groups.
2010-11-21 | E-GEOD-24452 | biostudies-arrayexpress
Project description:Sox2 is expressed by neural stem and progenitor cells, and a sox2 enhancer identifies these cells in the forebrains of both fetal and adult transgenic mouse reporters. We found that an adenovirus encoding EGFP placed under the regulatory control of a 0.4 kb sox2 core enhancer selectively identified multipotential and self-renewing neural progenitor cells in dissociates of human fetal forebrain. Gene expression analysis of E/sox2:EGFP-sorted neural progenitor cells, normalized to the unsorted forebrain dissociates from which they derived, revealed marked overexpression of genes within the notch and wnt pathways, and identified multiple elements of each pathway that appear selective to human neural progenitors. We used adenoviral E/sox2:EGFP to transduce dissociates of the second trimester human ventricular zone (VZ)/ subventricular zone (SVZ), followed by EGFP-directed fluorescence-activated cell sorting (FACS). The sox2 isolates and unsorted controls from different gestational ages (16-19 wks, n=4) were then subject to RNA extraction and hybridization on Affymetrix microarrays.
2011-02-25 | E-GEOD-27505 | biostudies-arrayexpress
Project description:Understanding the mechanism by which embryonic stem (ES) cells self-renew is critical for the realization of their therapeutic potential. Previously it had been shown that in combination with LIF, Id proteins were sufficient to maintain mouse ES cells in a self-renewing state. Here we investigate the requirement for Id1 in maintaing ES cell self-renewal and blocking differentiation. We find that Id1-/- ES cells have a propensity to differentiate and a decreased capacity to self-renew. Chronic or acute loss of Id1 leads to a down-regulation of Nanog, a critical regulator of self-renewal. In addition, in the absence of Id1, ES cells express elevated levels of Brachyury, a marker of mesendoderm differentiation. We find that loss of both Nanog and Id1 is required for the up-regulation of Brachyury, and Id1 maintains Nanog expression by blocking the expression of Zeb1, a repressor of Nanog transcription. These results identify Id1 as an important factor in the maintenance of ES cell self-renewal and suggest a plausible mechanism for its control of lineage commitment. Wild type and Id1-/- ES cells were grown on gelatin under normal self-renewing conditions (in the presence of serum and LIF).
2011-11-01 | E-GEOD-19144 | biostudies-arrayexpress
Project description:Background: Glioblastoma multiforme (GBM) is the most aggressive and most lethal primary malignant brain tumor, correlated with survival rates of less than one year from the time of diagnosis. Current surgical procedure attempts to remove the bulk of the tumor mass, whereas GBM frequently recurs within 1-3cm from the primary tumor resection site. Molecular mechanisms involved in the recurrence of the tumor are still poorly understood. The aim of the study was to define the molecular signature of GBM surrounding white matter (WM) in order to better understand the molecular mechanisms involved with tumor relapse. Material & Methods: Human GBM tumor bulk and surrounding tissue (1-3cm from the border of the tumor) were obtained from five patients who underwent total tumour resection, while normal white matter was harvested from patients who underwent surgical procedure for nonmalignant pathologies. Samples were processed for hybridization on the Affymetrix Human U133A arrays and data were examined with the GeneSpring analysis software. Results: Gene expression analysis of the samples was done in 2 independent steps. First, molecular profiling comparison of GBM surrounding WM and normal WM resulted in 59 genes differentially expressed between both tissues. Among these, numerous genes expressed by mature neural cells were down-regulated in GBM surrounding WM, while gene products supporting invasion were overexpressed. Moreover, KLRC1, a specific natural killer receptor naturally involved in the activation of antitumoral cells was drastically repressed in GBM surrounding WM, suggesting that the antitumoral immune surveillance is compromised in this tissue. Second, we focused our study on genes specifically regulated in GBM periphery respectively to GBM core. The highest up-regulated gene in GBM surrounding tissue encodes for DTX4, a regulator of NOTCH signalling pathway described for its key role in maintaining neural progenitors in an uncommitted state. Conclusion: This study revealed unique molecular characteristics of GBM surrounding tissue, showing the dysregulation of genes involved in immune surveillance along with genes associated to stemness maintenance. All together, these data may help to understand the molecular mechanisms associated with GBM recurrence This study attempted to define the molecular characteristics of the GBM surrounding tissue. To this end, GBM tumor samples were obtained from 5 patients who underwent total tumor resection. Surrounding tumor mass tissue was retrieved in all cases from not infiltrated white matter sited at 2 cm from the macroscopic tumor border. Furthermore, control white matter biopsies were harvested from patients operated on for deep intracerebral cavernomas. Each sample was hybridized onto Affymetrix human U133 arrays. For each patient, tumor core sample and surrounding tissue were harvested and are identified with the same suffix number. In 2 cases, (patients 3 and 4), two tumor peripheral tissue samples were harvested and are identified with the same number followed by "R" (replicate).
2009-06-15 | E-GEOD-13276 | biostudies-arrayexpress
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: SuperSeries DNA copy number and mRNA transcriptome of human glioblastoma tumors were profiled using Agilent and Affymetrix microarrays. This SuperSeries is composed of the following subset Series: GSE7602: Human GBM tumor vs Normal Human DNA GSE9171: Expression data from human GBM tumors and cell lines GSE9177: Human GBM tumor vs Normal Human DNA
2008-04-29 | E-GEOD-9200 | biostudies-arrayexpress
Project description:Current models imply that the FERM domain protein Merlin, encoded by the tumor suppressor NF2, inhibits mitogenic signaling at or near the plasma membrane. Here, we show that the closed, growth inhibitory form of Merlin accumulates in the nucleus, binds to the E3 ubiquitin ligase CRL4DCAF1, and suppresses its activity. Depletion of DCAF1 blocks the promitogenic effect of inactivation of Merlin. Conversely, enforced expression of a Merlin-insensitive mutant of DCAF1 counteracts the antimitogenic effect of Merlin. Re-expression of Merlin and silencing of DCAF1 induce a similar, tumor-suppressive program of gene expression. Tumor-derived mutations invariably disrupt Merlinâs ability to interact with or inhibit CRL4DCAF1. Finally, depletion of DCAF1 inhibits the hyperproliferation of Schwannoma cells from NF2 patients and suppresses the oncogenic potential of Merlin-deficient tumor cell lines. We propose that Merlin suppresses tumorigenesis by translocating to the nucleus to inhibit CRL4DCAF1. To examine if Merlin controls gene expression through inhibition of CRL4DCAF1, and define the general function of this ligase, we compared the gene expression program activated by expression of Merlin or by depletion of DCAF1 in Merlin-null FC-1801 mouse Schwannoma cells
2010-03-09 | E-GEOD-19305 | biostudies-arrayexpress
Project description:Endothelial differentiation occurs during normal vascular development in the developing embryo. Mouse embryonic stem (ES) cells were used to further define the molecular mechanisms of endothelial differentiation. By flow cytometry a population of VEGF-R2 positive cells was identified as early as 2.5 days after differentiation of ES cells, and a subset of VEGF-R2 + cells, that were CD41+ positive at 3.5 days. A separate population of VEGF-R2+ stem cells expressing the endothelial-specific marker CD144 (VE-cadherin) was also identified at this same time point. Microarray analysis of >45,000 transcripts was performed on RNA obtained from cells expressing VEGF-R2, CD41, and CD144. Experiment Overall Design: We identified four populations of cells; cells expressing VEGF-R2 (day 2.5), CD41 expressing cells (day 3.5), cells expressing CD144 (VE-Cadherin, day 3.5), and cells expressing CD144 (day 6.5). In addition to this, we have also obtained the negative control cells at each time such as VEGF-R2 (day 2.5) negative, CD41 negative (day 3.5), CD144 negative (VE-Cadherin, day 3.5), and negative CD144 (day 6.5). RNA for the microarray experiments were obtained in duplicate from two separately conducted experiments using the murine embryonic stem cells..
2008-10-20 | E-GEOD-10210 | biostudies-arrayexpress
Project description:To investigate the cooperative function Ets1 in macrophage, we generats Ets1 knockout mice.We then performed gene expression profiling analysis in macrophages seperated from either control or ko mice. We also performed Ets1 ChIP-seq, using M1 and M2 macrophages seperated from wild type C57 bone marrow, for mechanism study.
2024-10-01 | GSE271032 | GEO