Filters
Technology
Platform
GSE34044
Homo sapiens
8 Downloadable Samples
Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Tumors contain a fraction of cancer stem cells that maintain the propagation of the disease. The CD34CD38_ cells, isolated from acute myeloid leukemia (AML), were shown to be enriched leukemic stem cells (LSC). We isolated the CD34CD38_ cell fraction from AML and compared their gene expression profiles to the CD34CD38 cell fraction, using microarrays. We found 409 genes that were at least twofold over- or underexpressed between the two cell populations. These include underexpression of DNA repair, signal transduction and cell cycle genes, consistent with the relative quiescence of stem cells, and chromosomal aberrations and mutations of leukemic cells. Comparison of the LSC expression data to that of normal hematopoietic stem cells (HSC) revealed that 34% of the modulated genes are shared by both LSC and HSC, supporting the suggestion that the LSC originated within the HSC progenitors. We focused on the Notch pathway since Jagged-2, a Notch ligand was found to be overexpressed in the LSC samples. We show that DAPT, an inhibitor of gamma-secretase, a protease that is involved in Jagged and Notch signaling, inhibits LSC growth in colony formation assays. Identification of additional genes that regulate LSC self-renewal may provide new targets for therapy.
Publication Title
Gene expression profiles of AML derived stem cells; similarity to hematopoietic stem cells.
Sample Metadata Fields
Specimen part
View Samples- Pseudomonas aeruginosa
- 15 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
Biofilm formation and type III secretion have been shown to be reciprocally regulated in P. aeruginosa, and it has been suggested that factors related to acute infection may be incompatible
Publication Title
Biofilms and type III secretion are not mutually exclusive in Pseudomonas aeruginosa.
Sample Metadata Fields
No sample metadata fields
View Samples- Pseudomonas aeruginosa
- 4 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
Many Gram-negative bacteria employ cell-to-cell communication mediated by N-acyl homoserine lactones (quorum sensing) to control expression of a wide range of genes including, but not limited to, genes encoding virulence factors. Outside the laboratory, the bacteria live in complex communities where signals may be perceived across species. We here present a newly found natural quorum sensing inhibitor, produced by the pseudomonads Pseudomonas sp. B13 and Pseudomonas reinekei MT1 as a blind end in the biodegradation of organochloride xenobiotics, which inhibits quorum sensing in P.aeruginosa in naturally occurring concentrations. This catabolite, 4-methylenebut-2-en-4-olide, also known as protoanemonin, has been reported to possess antibacterial properties, but seems to have dual functions. Using transcriptomics and proteomics, we found that protoanemonin significantly reduced expression of genes and secretion of proteins known to be under control of quorum sensing in P.aeruginosa. Moreover, we found activation of genes and gene products involved in iron starvation response. It is thus likely that inhibition of quorum sensing, as the production of antibiotics, is a phenomenon found in complex bacterial communities.
Publication Title
Protoanemonin: a natural quorum sensing inhibitor that selectively activates iron starvation response.
Sample Metadata Fields
Compound
View Samples- Pseudomonas aeruginosa pao1, Pseudomonas aeruginosa
- 10 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
In the present in vitro study, interactions between P. aeruginosa (sessile biofilms as well as planktonic cells) and PMNs were analyzed by means of DNA microarray based transcriptomics. We found that the P. aeruginosa wild type biofilms, in contrast to planktonic cultures and quorum sensing (QS) deficient strains, respond to PMN exposure in a rather aggressive manner. The response does not involve protective mechanisms such as those involved in oxidative stress. Rather it is dominated by QS controlled virulence determinants such as those encoded by pqs, phz, rhlAB, all of which are designed to cripple Eukaryotic cells including PMNs and macrophages. Our comparative analysis supports the view that QS plays a major role in mechanisms by which P. aeruginosa evades host defense systems.
Publication Title
Pseudomonas aeruginosa recognizes and responds aggressively to the presence of polymorphonuclear leukocytes.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 52 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
In most organisms biological processes are partitioned, or phased to specific times over the day through interactions between external cycles of temperature (thermocycles) and light (photocycles), and the endogenous circadian clock. This orchestration of biological activities is achieved in part through an underlying transcriptional network. To understand how thermocycles, photocycles and the circadian clock interact to control time of day specific transcript abundance in Arabidopsis thaliana, we conducted four diurnal and three circadian two-day time courses using Affymetrix GeneChips (ATH1). All time courses were carried out with seven-day-old seedlings grown on agar plates under thermocycles (HC, hot/cold) and/or photocycles (LD, light/dark), or continuous conditions (LL, continuous light; DD, continuous dark, HH, continuous hot). Whole seedlings (50-100), including roots, stems and leaves were collected every four hours and frozen in liquid nitrogen. The four time courses interrogating the interaction between thermocycles, photocycles and the circadian clock were carried out as two four-day time courses. Four-day time courses were divided into two days under diurnal conditions, and two days under circadian conditions of continuous light and temperature. Thermocycles of 12 hours at 22C (hot) and 12 hours at 12C (cold) were used in this study. The two time courses interrogating photoperiod were conducted under short days (8 hrs light and 16 hrs dark) or long days (16 hrs light and 8 hrs dark) under constant temperature. In addition, the photoperiod time courses were in the Landsberg erecta (ler) accession, in contrast to the other time courses that are in the Columbia (col) background. The final time course interrogated circadian rhythmicity in seedlings grown completely in the dark (etiolated). Dark grown seedlings were synchronized with thermocycles, and plants were sampled under the circadian conditions of continuous dark and temperature.
Publication Title
Network discovery pipeline elucidates conserved time-of-day-specific cis-regulatory modules.
Sample Metadata Fields
Age, Time
View Samples- Macaca mulatta, Homo sapiens
- 105 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20), Affymetrix Rhesus Macaque Genome Array (rhesus)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Transcriptome analysis of GVHD reveals aurora kinase A as a targetable pathway for disease prevention.
Sample Metadata Fields
Specimen part, Subject
View Samples- Macaca mulatta
- 81 Downloadable Samples
Affymetrix Rhesus Macaque Genome Array (rhesus)
Description
Graft versus host disease (GVHD) is the most common complication of hematopoietic stem cell transplant (HCT). However, our understanding of the molecular pathways that cause this disease remains incomplete, leading to inadequate treatment strategies. To address this, we measured the gene expression profile of non-human primate (NHP) T cells during acute GVHD. This transcriptome analysis enables an unsupervised approach to the identification of targets for disease control using a model with an immune system that closely overlaps with the human and has a high degree of cross-reactivity with human antibody-based therapeutics.
Publication Title
Transcriptome analysis of GVHD reveals aurora kinase A as a targetable pathway for disease prevention.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 24 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
Graft versus host disease (GVHD) is the most common complication of hematopoietic stem cell transplant (HCT). However, our understanding of the molecular pathways that cause this disease remains incomplete, leading to inadequate treatment strategies. To address this, we measured the gene expression profile of non-human primate (NHP) T cells during acute GVHD (GSE73723). Within these profiles we discovered potentially druggable targets not previously implicated in GVHD, prominently including aurora kinase A (AURKA). In this study, we performed a planned comparison of AURKA gene expression in HCT-recipients with clinical GVHD and compared it to expression in HCT-recipients without clinical GVHD.
Publication Title
Transcriptome analysis of GVHD reveals aurora kinase A as a targetable pathway for disease prevention.
Sample Metadata Fields
Specimen part, Subject
View Samples