Tight regulation of hematopoietic stem cell (HSC) homeostasis is essential for life-long hematopoiesis, for preventing blood cancers and for averting bone marrow failure. The underlying mechanisms are incompletely understood. Here, we identify production of inositol-tetrakisphosphate (IP4) by inositoltrisphosphate 3-kinase B (ItpkB) as essential for HSC quiescence and function. Young ItpkB-/- mice accumulated phenotypic HSC and showed extramedullary hematopoiesis. ItpkB-/- HSC were less quiescent and proliferated more than wildtype controls. They downregulated quiescence and stemness associated mRNAs, but upregulated activation, oxidative metabolism, protein synthesis and lineage associated transcripts. Although they showed no significant homing defects, ItpkB-/- HSC had a severely reduced competitive long-term repopulating potential. Aging ItpkB-/- mice lost hematopoietic stem and progenitor cells and died with severe anemia. Wildtype HSC normally repopulated ItpkB-/- hosts, incidating a HSC-intrinsic ItpkB requirement. ItpkB-/- HSC had reduced cobblestone-area forming cell activity in vitro and showed increased stem-cell-factor activation of the phosphoinositide 3-kinase (PI3K) effector Akt, reversed by exogenous provision of the known PI3K/Akt antagonist IP4. They also showed transcriptome changes consistent with hyperactive Akt/mTOR signaling. Thus, we propose that ItpkB ensures HSC quiescence by limiting cytokine-induced PI3K signaling in HSC. Overall design: For each of 3 replicate ItpkB-/- or wt samples, we enriched Lin- cells from BM of 4 pooled age-matched mice with Rapidspheres (Stemcell Technologies), FACS-sorted =10,000 LSK CD34-CD150+CD48-Flk2- LT-HSC into lysis buffer and prepared RNA with RNeasy Micro kits (Quiagen). RNA sequencing was done using an Illumina HISeq Analyzer 2000, Casava v1.8.2 genome analyzer pipeline, TopHat v1.4.1/Bowtie2 genome alignment and Partek v6.6 mRNA annotation software. Statistical analyses were done with edgeR (Bioconductor package), excluding genes with false discovery rates >0.15, fold-change magnitudes =1.4 and log2(counts per million) =4 to avoid undefined values and the poorly defined log fold-changes for low counts close to 0. Unsupervised clustering of 441 significantly changed genes was done with dChip using rank correlation and a centroid linkage method. Scatter plots were generated in Spotfire. GSEA was performed with gene set permutation, using gene sets from MSigDB (www.broadinstitute.org/gsea/msigdb/index.jsp) or manually curated from, excluding genes without HUGO approved symbols
IP3 3-kinase B controls hematopoietic stem cell homeostasis and prevents lethal hematopoietic failure in mice.
No sample metadata fields
View SamplesWe performed microarray analysis in order to evaluate the combination effect of the mitochondrial matrix chaperone inhibitor gamitrinib-triphenylphosphonium (G-TPP) and Liver X receptor agonist LXR623 on gene expression in stem cell like glioma cells (NCH644).
Activation of LXR Receptors and Inhibition of TRAP1 Causes Synthetic Lethality in Solid Tumors.
Specimen part, Cell line, Treatment
View SamplesQuiescent stem cells are periodically activated to maintain tissue homeostasis or occasionally called into action upon injury. Molecular mechanisms that constitutively maintain stem cell identity or promote stem cell proliferation and differentiation upon activation have been extensively studied. However, it is unclear how quiescent stem cells maintain identity and reinforce quiescence when they transition from quiescence to activation. Here we show mouse hair follicle stem cell compartment induces a transcription factor, Foxc1, when activated. Importantly, deletion of Foxc1 in the activated but not quiescent stem cells compromises stem cell identity, fails to re-establish quiescence and subsequently drives premature stem cell activation.These findings uncover a dynamic, cell-intrinsic mechanism employed by hair follicle stem cells to reinforce stemness in response to activation. Overall design: Poly(A)-enriched transcriptome RNA-seq on HFSCs isolated in WT and K14Cre cKO mice at anagen and early telogen stage of hair cycle.
Foxc1 reinforces quiescence in self-renewing hair follicle stem cells.
No sample metadata fields
View SamplesU87 cells were transduced with IDH1 WT or IDH1 R132H and stable clones were selected.
Induction of synthetic lethality in IDH1-mutated gliomas through inhibition of Bcl-xL.
Specimen part
View SamplesTo assess the effect of different forms of TL1A within different organs of the mouse we generated 2 different transgenic mouse lines where TL1A was expressed under the control of the CD2 promoter. 2 forms of TL1A was used. Either WT TL1A, which led to over expression of both membrane bound and soluble forms of TL1A (Refered to as Mem+Sol) or TL1A Delta 69-93 which only overexpressed membrane restricted TL1A (Refered to as Mem). Lungs and terminal ileums were taken from Either Mem, Mem+sol or WT litermate control mice at 12 weeks of age and the transcriptome assessed using RNAseq Through this we demonstrated enrichment of different transcripts and pathways both dependent on and independent of the form of TL1A and the site of action. This study is also the first to use RNASeq to assess the resualt of overexpression of TL1A within the mouse. Overall design: Poly-A purified mRNA profiles from the Ileum and Lung of Mem, Mem+Sol and WT mice generated using Illumina based RNASeq
Cleavage of TL1A Differentially Regulates Its Effects on Innate and Adaptive Immune Cells.
Sex, Specimen part, Subject
View SamplesTranscriptional profiling of guard cells and mesophyll cells in response to ABA treatment
Isolation of a strong Arabidopsis guard cell promoter and its potential as a research tool.
Specimen part, Disease, Disease stage, Compound
View SamplesBackground: Isolation and characterization of tumourigenic colon cancer initiating cells may help to develop novel diagnostic and therapeutic procedures. Methods: We characterized a panel of fourteen human colon carcinoma cell lines and their corresponding xenografts for the surface expression of different potential stem cell markers: CD133, CD24, CD44, CDCP1 and CXCR4. In five cell lines and nine xenografts mRNA expression of the investigated markers was determined. Tumour growth behaviour of CD133+, CD133- and unsorted SW620 cells was evaluated in vivo. Results: All surface markers showed distinct expression patterns in the examined tumours. Analyses of the corresponding xenografts revealed a significant reduction of cell numbers expressing the investigated markers. CD44 and CXCR4 mRNA expression correlated within the cell line panel and CD44 and CDCP1 within the xenograft panel, respectively. Small subpopulations of double and triple positive cells could be described. SW620 showed significantly higher take rates and shorter doubling times in vivo when sorted for CD133 positivity. Conclusion: Our data support the hypothesis of a small subset of cells with stem cell-like properties characterized by a distinct surface marker profile. In vivo growth kinetics give strong relevance for an important role of CD133 within the mentioned surface marker profile.
Characterization of colon cancer cells: a functional approach characterizing CD133 as a potential stem cell marker.
Sex, Age, Specimen part
View SamplesWe identified Ncoa3 as a regulator of neuronal morphology and microRNA activity. In order to uncover target genes of this transcriptional coactivator we performed this microarray analysis.
A large-scale functional screen identifies Nova1 and Ncoa3 as regulators of neuronal miRNA function.
Specimen part, Treatment
View SamplesThe Fra-1 transcription factor promotes tumor cell growth, invasion and metastasis. While characterizing five breast cancer cell lines derived from primary human breast tumors, we identified BRC-31 as a novel basal-like cell model that expresses elevated Fra-1 levels. BRC-31 cells display elevated FAK, SRC and ERK2 phosphorylation relative to luminal breast cancer models. Inhibition of this signaling axis, through the use of pharmacological inhibitors, reduces the phosphorylation and stabilization of Fra-1. Elevated integrin V3 expression in these cells suggested that integrin receptors might activate this FAK-SRC-ERK2 signaling axis to enhance Fra-1 phosphorylation. These cells also express high levels of uPAR, a GPI-anchored receptor that has been shown to enhance integrin-mediated signaling initiated by Vitronectin engagement. Transient knockdown of uPAR in BRC31 cells grown on Vitronectin reduces Fra-1 phosphorylation and stabilization and uPAR and Fra-1 are required for Vitronectin-induced cell invasion. In clinical samples, a molecular component signature consisting of Vitronectin-uPAR-uPA-Fra-1 predicts poor overall survival in patients with breast cancer and correlates with a Fra-1 transcriptional signature. Taken together, we have identified a novel-signaling axis that leads to phosphorylation and stabilization of Fra-1, a transcription factor that is emerging as an important modulator of breast cancer progression and metastasis.
Integrin-uPAR signaling leads to FRA-1 phosphorylation and enhanced breast cancer invasion.
Age, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Transcriptional code and disease map for adult retinal cell types.
Specimen part
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