Oxygen regulation of immunogenicity in primary human glioma cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Aaron Sarver
PROVIDER: E-GEOD-28316 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Dendritic Cell (DC) vaccination is a powerful approach for cancer immunotherapy that has recently obtained regulatory approval, and tumor lysate-pulsed DC vaccines are being tested in clinical trials. Tumor cell lysates (TLs) are often generated from cells cultured in atmospheric oxygen (~20% O2), which is roughly four-fold higher than that of the tumor in situ. We analyzed the expression patterns of glioma cells cultured in 5% Oxygen, 20% Oxygen and the primary tumors which the cell cultures were derived.
2013-01-01 | GSE28316 | GEO
Project description:Hypoxia is negatively associated with glioblastoma patient survival and contributes strongly to tumor resistance. Unfortunately novel anti-angiogenic therapy increases hypoxia and activates survival pathways in tumor cells leading to inevitable tumor relapse. Here we demonstrate that primary glioma cultures and cell lines depend on autophagy to survive severe hypoxia but also at normal oxygen levels. Positive regulators of autophagy are expressed at higher levels in tumor cells and induction in severe hypoxia is more prominent compared to normal brain cells. We demonstrate that autophagy is an essential/critical target for novel treatment in glioblastoma. We show ATG9A is induced by severe hypoxia and could be a novel player of the autophagic response in glioma cells. ATG9A targeting inhibited tumor growth, suggesting an essential role in glioma cell survival in vivo. While autophagy induction was also observed in normal astrocytes, glioma cells displayed a higher sensitivity towards autophagy inhibitors. Importantly, patient-derived cultures exhibited varying sensitivity towards anti-autophagy treatment, where certain cultures were dependent on autophagy already in normoxic conditions. The treatment of tumor bearing mice with the autophagy inhibitor chloroquine significantly increased mice survival, but combination treatment of the agent with bevacizumab did not reveal additive or synergistic effect. The present study demonstrates that inhibition of autophagy using chloroquine as a single agent provides a novel treatment strategy against glioblastoma. It remains to be seen whether autophagy inhibition will improve current standard of care treatment of newly diagnosed glioblastoma patients and whether more specific inhibitors will lead to stronger therapeutic outcome. (Provisional)
2015-11-10 | E-MTAB-3085 | biostudies-arrayexpress
Project description:Two lung adenocarcinoma cell lines, A549 and SPC-A1, were cultured under two different oxygen concentrations, 1% and 20%, respectively. After 24 hours cultured, cells were collected and total RNA was extracted. Affymetrix GeneChip® Gene 1.0 ST Array System for Human was applied to detect the differences of gene expression of lung adenocarcinoma cell lines cultured under different oxygen concentrations (total RNA of the two cells was pooled with equal quantity). The experiments were repeated with the same procedures except culturing tumor cell lines in matrigel.
2015-04-30 | E-MTAB-3512 | biostudies-arrayexpress
Project description:The mechanisms by which the placenta adapts to exogenous stimuli to create a stable and healthy environment for the growing fetus are not well known. Low oxygen tension and sub-optimal vitamin D levels influence placental function and both are associated with preeclampsia, a condition associated with altered development of placental trophoblast. We hypothesized that oxygen tension, vitamin D levels, or both affect villous trophoblast by modulation of gene expression through DNA methylation. To test this we used the Illumina Infinium Human Methylation 450 BeadChip array to compare the DNA methylation profile of primary cultures of human cytotrophoblasts and syncytiotrophoblasts under three oxygen tensions and three vitamin D levels. We found no effect on global DNA methylation by either treatment, but a limited set of loci became hypermethylated in cytotrophoblasts exposed for 24 hours to 1% oxygen, as compared to the same cells exposed to 8% or 20% oxygen. Vitamin D levels had no detectable effect on methylation profiles in either trophoblast type. Hypermethylation with low oxygen tension was independently confirmed by bisulfite-pyrosequencing in a subset of functionally important genes including CP, ITGA5, SOD2, XDH and ZNF2. Intriguingly, 70 out of the 147 hypoxia-associated CpGs, overlapped with CpG sites that become hypomethylated upon differentiation of cytotrophoblasts into syncytiotrophoblasts. Furthermore, the preponderance of altered sites was located at AP-1 binding sites. We suggest that AP-1 expression is triggered by hypoxia and interacts with DNA methyltransferases (DNMTs) to target methylation at specific sites in the genome, thus causing suppression of the associated genes that are responsible for differentiation of villous cytotrophoblast to syncytiotrophoblast. RNA from cytotrophoblast from 2 placentas exposed to 3 different conditions of hypoxia (1%,8%,20%) and treated with 3 levels of vitamin D were run on the Illumina HT-12v4 Expression Array
2013-01-18 | E-GEOD-41331 | biostudies-arrayexpress
Project description:Hypoxia is a low oxygen condition that occurs in the developing tumor mass and that is associated with poor prognosis and resistance to chemo- and radio-therapy. The definition of the hypoxia gene signature is fundamental for the understanding of tumor biology, as in the case of neuroblastoma, the most common pediatric solid tumor. The issue of identifying a significant group of variables in microarray gene expression experiments is particularly difficult due to the typical high dimensional nature of the data and great effort has been spent in the development of feature selection techniques. Our main goal is to define a robust hypoxia gene signature in neuroblastoma cell lines. A set of 11 neuroblastoma cell lines were cultured under normoxic and hypoxic conditions for 18 hours, and their gene expression profiles were measured with Affymetrix GeneChip HG-U133 Plus 2.0. We used the l1-l2 regularization framework in order to select the significant probesets defining hypoxic versus normoxic cell lines. Experiment Overall Design: The expression profiles of 11 neuroblastoma cell lines under normoxia vs hypoxia were studied.
2009-10-10 | E-GEOD-17714 | biostudies-arrayexpress
Project description:Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults, with glioma initiating cells (GICs) implicated to be critical for tumor progression and resistance to therapy. The hypoxic tumor microenvironment has been shown to play an important role to maintain the GICs; however, the mechanisms regulating responses of GICs to hypoxia remain poorly understood. We used microarray to to detail the global change of gene expression in GICs cultured under hypoxia compared to normoxia and identified de-regulated genes during hypoxia. CD133+ D456MG GICs were cultured under 1% O2 or 20% O2 for 12 hours. Then RNA was extracted and gene expression was profiled by microarray.
2016-07-03 | E-GEOD-73556 | biostudies-arrayexpress
Project description:The mechanisms by which the placenta adapts to exogenous stimuli to create a stable and healthy environment for the growing fetus are not well known. Low oxygen tension and sub-optimal vitamin D levels influence placental function and both are associated with preeclampsia, a condition associated with altered development of placental trophoblast. We hypothesized that oxygen tension, vitamin D levels, or both affect villous trophoblast by modulation of gene expression through DNA methylation. To test this we used the Illumina Infinium Human Methylation 450 BeadChip array to compare the DNA methylation profile of primary cultures of human cytotrophoblasts and syncytiotrophoblasts under three oxygen tensions and three vitamin D levels. We found no effect on global DNA methylation by either treatment, but a limited set of loci became hypermethylated in cytotrophoblasts exposed for 24 hours to 1% oxygen, as compared to the same cells exposed to 8% or 20% oxygen. Vitamin D levels had no detectable effect on methylation profiles in either trophoblast type. Hypermethylation with low oxygen tension was independently confirmed by bisulfite-pyrosequencing in a subset of functionally important genes including CP, ITGA5, SOD2, XDH and ZNF2. Intriguingly, 70 out of the 147 hypoxia-associated CpGs, overlapped with CpG sites that become hypomethylated upon differentiation of cytotrophoblasts into syncytiotrophoblasts. Furthermore, the preponderance of altered sites was located at AP-1 binding sites. We suggest that AP-1 expression is triggered by hypoxia and interacts with DNA methyltransferases (DNMTs) to target methylation at specific sites in the genome, thus causing suppression of the associated genes that are responsible for differentiation of villous cytotrophoblast to syncytiotrophoblast. DNA from 2 cell types from 5 placentas exposed to 3 different conditions of hypoxia (1%,8%,20%) and treated with 3 levels of vitamin D were bisulfite converted and run on the Illumina HumanMethylation450 BeadChip
2013-01-18 | E-GEOD-41336 | biostudies-arrayexpress
Project description:Senescent is an irreversible form of cell cycle arrest initiated by damaged cell constituents and subsequent pro-oncogenic signaling. Replicative senescence in vitro can be considered a model for human aging. When fibroblasts are cultured under atmospheric oxygen conditions of 20%, typical of normal tissue culture procedure, fibroblasts generally reach their replicative capacity at 50-60 population doublings (PDs). When fibroblasts are cultured under normal physiological oxygen conditions of 3%, PDs increase about 30% relative to atmospheric levels. Hence while oxygen is a requirement for normal aerobic respiration, it can contribute to the total amount of oxidative stress to which cells are exposed to, leading to a long-term adverse effect in vitro. Inasmuch, cultures maintained under hyperoxic and hypoxic conditions provide a convenient model system for assessing the relationship between oxygen/oxidative stress and senescence. We used microarrays to profile the changes in global gene expression during aging and senescence of Imr90 cells under growth oxygen conditions of 3% and 20%. Imr90 cells at various population doubling timepoints (young, old, and senescent) grown separately under 3 and 20% oxygen growth conditions were selected for RNA extraction and hybridization on Affymetrix microarrays. Timepoints from cells grown under 3% and 20% oxygen conditions were age matched via population doublings to ensure accurate cross sample comparison.
2010-03-06 | E-GEOD-19018 | biostudies-arrayexpress
Project description:Hypoxia is a low oxygen condition that occurs in the developing tumor mass and that is associated with poor prognosis and resistance to chemo- and radio-therapy. The definition of the hypoxia gene signature is fundamental for the understanding of tumor biology, as in the case of neuroblastoma, the most common pediatric solid tumor. The issue of identifying a significant group of variables in microarray gene expression experiments is particularly difficult due to the typical high dimensional nature of the data and great effort has been spent in the development of feature selection techniques. Our main goal is to define a robust hypoxia gene signature in neuroblastoma cell lines. A set of 9 neuroblastoma cell lines were cultured under normoxic and hypoxic conditions for 18 hours, and their gene expression profiles were measured with Affymetrix GeneChip HG-U133 Plus 2.0. The clustering analysis of the expression profiles based on different clustering methods consistently revealed that hypoxia was not the major factor characterizing the data set. T-test analysis with multiple testing correction fails to identify significantly differentially expressed genes. Conversely the l1-l2 regularization selects 11 significant probesets while building an effective classification rule. The algorithm is cast within a cross-validation framework in order to achieve an unbiased analysis. The estimated cross-validation error is 17% (3 out of 18). We show that the use of l1-l2 regularization allowed us to model the effect of hypoxia, which was not detected by conventional t-test based approaches and we find a panel of genes able to properly discriminate the normoxic versus the hypoxic status of neuroblastoma cell lines. Experiment Overall Design: The expression profile of 9 neuroblastoma cell lines under normoxia vs hypoxia was studied
2009-04-24 | E-GEOD-15583 | biostudies-arrayexpress
Project description:Transcriptomic analyses of the oxygen response of two glioma cell lines at 20% versus 0.3% O2, and 3% vs 0.3% O2 in the presence or absence of serum 22 samples are analysed with three or more biological replicates in different O2 concentrations.
2013-04-05 | E-GEOD-32100 | biostudies-arrayexpress