This SuperSeries is composed of the SubSeries listed below.
Critical Role of STAT5 transcription factor tetramerization for cytokine responses and normal immune function.
Specimen part, Treatment, Time
View SamplesCytokine-activated STAT proteins dimerize and bind to high-affinity motifs, and N-terminal domain-mediated oligomerization of dimers allows tetramer formation and binding to low-affinity tandem motifs, but the functions of dimers versus tetramers are unknown. We generated Stat5a and Stat5b double knock-in (DKI) N-domain mutant mice that form dimers but not tetramers, identified cytokine-regulated genes whose expression required STAT5 tetramers, and defined consensus motifs for dimers versus tetramers. Whereas Stat5- deficient mice exhibited perinatal lethality, DKI mice were viable, indicating that STAT5 dimers were sufficient for survival. Nevertheless, STAT5 DKI mice had fewer CD4+CD25+ T cells, NK cells, and CD8+ T cells, with impaired cytokine-induced proliferation and homeostatic proliferation of CD8+ T cells. DKI CD8+ T cell proliferation following viral infection was diminished and DKI Treg cells did not efficiently control colitis. Thus, tetramerization of STAT5 is dispensable for survival but is critical for cytokine responses and normal immune function.
Critical Role of STAT5 transcription factor tetramerization for cytokine responses and normal immune function.
Specimen part, Treatment, Time
View SamplesMalignant gliomas constitute one of the most significant areas of unmet medical need, due to the invariable failure of surgical eradication and their marked molecular heterogeneity. Accumulating evidence has revealed a critical contribution by the Polycomb axis of epigenetic repression. However, a coherent understanding of the regulatory networks affected by Polycomb during gliomagenesis is still lacking. Here we integrate transcriptomic and epigenomic analyses to define Polycomb-dependent networks that promote gliomagenesis, validating them both in two independent mouse models and in a large cohort of human samples. We found that Polycomb dysregulation in gliomagenesis affects transcriptional networks associated to invasiveness and de-differentiation. The dissection of these networks uncovers Zfp423 as a crtitical Polycomb-dependent transcription factor whose silencing negatively impacts survival. The anti-gliomagenic activity of Zfp423 requires interaction with the SMAD proteins within the BMP signaling pathway, pointing to a novel synergic circuit through which Polycomb inhibits BMP signaling. Overall design: Transcriptomic analysis of two different stages of gliomagenesis
Polycomb dysregulation in gliomagenesis targets a Zfp423-dependent differentiation network.
Specimen part, Cell line, Subject
View SamplesPancreatic ductal adenocarcinoma (PDAC) is a nearly uniformly lethal malignancy, with most patients facing an adverse clinical outcome. Given the pivotal role of aberrant Notch signaling in the initiation and progression of PDAC, we investigated the effect of MRK-003, a potent and selective -secretase inhibitor, in preclinical PDAC models. We used a panel of human PDAC cell lines, as well as patient-derived PDAC xenografts, to determine whether pharmacological targeting of the Notch pathway could inhibit pancreatic tumor growth and potentiate gemcitabine sensitivity. In vitro, MRK-003 treatment downregulated the canonical Notch target gene Hes-1, significantly inhibited anchorage independent growth, and reduced the subset of CD44+CD24+ and aldehyde dehydrogenase (ALDH)+ cells that have been attributed with tumor initiating capacity. Ex vivo pretreatment of PDAC cells with MRK-003 in culture significantly inhibited the subsequent engraftment in immunocompromised mice. In vivo, MRK-003 monotherapy significantly blocked tumor growth in 5 of 9 (56%) patient-derived PDAC xenografts. Moreover, a combination of MRK-003 and gemcitabine showed enhanced antitumor effects compared to gemcitabine alone in 4 of 9 (44%) PDAC xenografts. Baseline gene expression analysis of the treated xenografts indicated that upregulation of nuclear factor kappa B (NFB) pathway components was associated with the sensitivity to single MRK-003, while upregulation in B-cell receptor (BCR) signaling and nuclear factor erythroid-derived 2-like 2 (NRF2) pathway correlated with response to the combination of MRK-003 with gemcitabine. The preclinical findings presented here provide further rationale for small molecule inhibition of Notch signaling as a therapeutic strategy in PDAC.
The gamma secretase inhibitor MRK-003 attenuates pancreatic cancer growth in preclinical models.
Specimen part
View SamplesCancer cells alter their metabolism to support their malignant properties. By transcriptomic analysis we identified the glucose-transforming polyol pathway (PP) gene aldo-keto-reductase-1-member-B1 (AKR1B1) as strongly correlated with epithelial-to-mesenchymal transition (EMT). This association was confirmed staining samples from lung cancer patients and from an EMT-driven colon cancer mouse model with p53 deletion. In vitro, mesenchymal-like cancer cells showed increased AKR1B1 levels and AKR1B1 knockdown was sufficient to revert EMT. An equivalent level of EMT suppression was measured by targeting the downstream enzyme sorbitol-dehydrogenase (SORD), further pointing at the involvement of the PP. Comparative RNA sequencing profiling confirmed a profound alteration of EMT in PP-deficient cells, revealing a strong repression of TGF-Beta signature genes. Mechanistically, excess glucose was found to promote EMT through autocrine TGF-Beta stimulation, while PP-deficient cells were refractory to glucose-induced EMT. PP represents a molecular link between glucose metabolism and cancer differentiation and aggressiveness, and a novel potential therapeutic target. Overall design: 3x3 biological replicated samples; 2 groups of samples with shRNA-mediated specific gene inhibition and scrambled control cells
Polyol Pathway Links Glucose Metabolism to the Aggressiveness of Cancer Cells.
Cell line, Treatment, Subject
View SamplesTransdifferentiation of fibroblasts into induced Neuronal cells (iNs) by neuronal-specific transcription factors Brn2, Myt1l and Ascl1 is a paradigmatic example of inter-lineage conversion across epigenetically distant cells. Despite tremendous progress on the transcriptional hierarchy underlying transdifferentiation, the enablers of the concomitant epigenome resetting remain to be elucidated. Here we investigated the role of KMT2A and KMT2B, two histone H3 lysine 4 methylases with cardinal roles in development, through individual and combined inactivation. We found that Kmt2b, whose human homologue's mutations cause dystonia, is selectively required for iN conversion through the suppression of the alternative myocyte program and the induction of neuronal maturation genes. Overall design: In order to study the role of KMT2A and KMT2B during transdifferentiation, we employed conditional mouse strains carrying: i) the exon 2 of Kmt2a and/or Kmt2b flanked by LoxP sites; ii) the knock-in of the YFP-coding gene into one Rosa26 allele, downstream of a LoxP-flanked transcription termination cassette (STOP cassette); and iii) the gene coding for the tamoxifen-inducible version of Cre recombinase knocked into the second Rosa26 allele (Glaser et al., 2006; Kranz et al., 2010; Testa et al., 2004). MEFs were derived from Kmt2a (and/or Kmt2b)fl/fl Cre+ YFP+ embryos and from Kmt2a+/+Kmt2b+/+ Cre+ YFP+ or Kmt2afl/+ Cre+ YFP+ for Kmt2a conditional KO (cKO) as controls (Figure 1A), and were subjected to transdifferentiation. After 13 days of BAM treatment, cells were FACS sorted for PSA-NCAM expression, and the transcriptome of positive and negative cells were independently profiled.
KMT2B Is Selectively Required for Neuronal Transdifferentiation, and Its Loss Exposes Dystonia Candidate Genes.
Specimen part, Subject
View Samples10 day old seedlings were treated with 5uM of the cytokinin Benzyladenine(BA)or DMSO at 15min, 45min, 120min, 480min and 1440min
Expression profiling of cytokinin action in Arabidopsis.
Age, Compound, Time
View SamplesThe use of yeast as a delivery system is an attractive option for the oral administration of therapeutic agents. We recently developed mutants of Saccharomyces cerevisiae capable of lysis upon conditional down-regulation of the expression of the cell wall genes PKC1 and SRB1. The lysis mechanism of the mutant is based on the use of the MET3 promoter, which, upon addition of methionine and cysteine, blocks transcription of SRB1 and PKC1. This strain has the potential to be an integral part of an oral yeast delivery system, in which there is lysis of yeasts in the human gut, followed by release of recombinant proteins for therapeutic use. In order to provide proof-of-principle, the system was evaluated testing the cells viability and lysis performance under conditions, which simulate those found in the human stomach and the duodenum. Upon incubation of yeast cells in these conditions, lysis could be induced and was accompanied by release of GFP reporter protein into the medium. However, the conditional lysis mechanism based on the MET3 promoter is not applicable in vivo. Therefore, alternative promoters suitable for in-vivo down-regulation of SRB1 and PKC1 were identified by a microarray experiments. The transcripts of genes ANB1, TIR1, and MF(ALPHA)2 were significantly reduced upon exposure of the yeast cells to conditions of the two gut compartments. Their promoters could be used to down-regulate SRB1/VIG9 and PKC1 in vivo to achieve lysis of the yeast in the gut to release cargo therapeutic proteins.
Conditional cell-wall mutants of Saccharomyces cerevisiae as delivery vehicles for therapeutic agents in vivo to the GI tract.
No sample metadata fields
View SamplesHere we show that biotin-labelled miR-34a can be loaded to AGO2, and AGO2 immunoprecipitation can pulldown biotinylated miR-34a (Bio-miR pulldown). RNA-sequencing (RNA-seq) of the Bio-miR pulldown RNAs efficiently identified miR-34a mRNA targets, which could be verified with luciferase assays. In contrast to the approach of Bio-miR pulldown, RNA-seq of miR-34a overexpression samples had limited value in identifying direct targets of miR-34a. It seems that pulldown of 30 -Biotin-tagged miRNA can identify bona fide microRNA targets at least for miR34a. Overall design: biotin-labelled miR-34a pulldown and RNA sequencing of miR-34a overexpression samples
Comparing two approaches of miR-34a target identification, biotinylated-miRNA pulldown vs miRNA overexpression.
Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
7q11.23 dosage-dependent dysregulation in human pluripotent stem cells affects transcriptional programs in disease-relevant lineages.
Sex, Specimen part, Subject
View Samples