We addressed the clinical significance and mechanisms behind in vitro cellular responses to ionising radiation (IR)-induced DNA double strand breaks in 74 paediatric ALL patients. We found an apoptosis-resistant response in 36% of patients and an apoptosis-sensitive response in the remaining 64% of leukaemias. Global gene expression profiling of 11 apoptosis-resistant and 11 apoptosis-sensitive ALLs revealed abnormal up-regulation of multiple pro-survival pathways in response to IR in apoptosis-resistant leukaemias and differential post-transcriptional activation of the PI3-Akt pathway was observed in representative resistant cases. It is possible that abnormal pro-survival responses to DNA damage provide one of the mechanisms of primary resistance in ALL .
Stratification of pediatric ALL by in vitro cellular responses to DNA double-strand breaks provides insight into the molecular mechanisms underlying clinical response.
No sample metadata fields
View SamplesGene expression analyis of primary MCL including IGHV mutated and unmutated cases
Molecular subsets of mantle cell lymphoma defined by the IGHV mutational status and SOX11 expression have distinct biologic and clinical features.
Specimen part, Disease, Disease stage
View SamplesThe myogenic regulatory factor MRF4 is expressed at high levels in myofibers of adult skeletal muscle, but its function is unknown. Here we show that knockdown of MRF4 in adult muscle causes hypertrophy and prevents denervation-induced atrophy. This effect is accompanied by increased protein synthesis and the widespread activation of genes involved in muscle contraction, excitation-contraction coupling and energy metabolism, many of which are known targets of MEF2 transcription factors. Genes regulated by MEF2 represent the top-ranking gene set enriched after Mrf4 RNAi, and a MEF2 reporter is inhibited by co-transfected MRF4 and activated by Mrf4 RNAi. The role of MEF2 in mediating the effect of MRF4 knockdown is supported by the finding that Mrf4 RNAi-dependent increase in fiber size is prevented by dominant negative MEF2, while constitutively active MEF2 is able to induce myofiber hypertrophy. The nuclear localization of the MEF2 co-repressor HDAC4 is impaired by Mrf4 knockdown, suggesting that MRF4 acts by stabilizing a repressor complex that controls MEF2 activity. The demonstration that fiber size in adult skeletal muscle is controlled by the MRF4-MEF2 axis opens new perspectives in the search for therapeutic targets to prevent muscle wasting, in particular sarcopenia and cachexia.
MRF4 negatively regulates adult skeletal muscle growth by repressing MEF2 activity.
Specimen part
View SamplesTo identify the “time-lapse” TF networks during B lineage commitment, we established multipotent progenitors harboring a tamoxifen-inducible form of Id3, an in vitro system where virtually all cells became B cells within 6 days by simply withdrawing 4-OHT. In this study, transcriptome analysis at multiple time points was performed using the culture system. Overall design: Time-course transcriptomic profiles of multipotent iLS cells toward B committed cells were analyzed by deep sequencing, basically in triplicate, using Illumina Hiseq platform.
Three-step transcriptional priming that drives the commitment of multipotent progenitors toward B cells.
Specimen part, Cell line, Subject, Time
View SamplesIt is now well established that the E- and Id-protein axis regulates multiple steps in lymphocyte development. However, it remains unknown as to how E- and Id-proteins mechanistically enforce and maintain the naïve T cell fate. Here we show that Id2 and Id3 suppressed the development and expansion of innate-variant TFH cells. Innate-variant TFH cells required MHC Class I-like signalling and were associated with germinal center B cell development. We found that Id2 and Id3 induced Foxo1 and Foxp1 expression to antagonize the activation of TFH transcription signature. We show that Id2 and Id3 acted upstream of the Hif1a/Foxo/AKT/mTORC1 pathway as well as the c-myc/p19Arf module to control cellular expansion and activation. We found that mice depleted for Id2 and Id3 expression developed colitis and aß T cell lymphomas. Lymphomas depleted for Id2 and Id3 expression displayed elevated levels of c-myc whereas p19Arf abundance declined. Transcription signatures of Id2- and Id3-depleted lymphomas revealed similarities with genetic deficiencies associated with Burkitt lymphoma. We propose that in response to antigen receptor and/or cytokine signaling the E-Id protein axis modulates the activities of the PI3K-AKT-mTORC1-Hifa and c-myc/p19Arf pathways to control cellular expansion and homeostatic proliferation. Overall design: RNA-seq data of 5 of wild type CD4SP cells, 3 of wild type Tfh cells, 3 of Id3-/- CD4SP cells, 3 of Id2-/-Id3-/-(dKO) CD4SP cells, and 6 of Id2-/-Id3-/- lymphoma cells.
The E-Id protein axis modulates the activities of the PI3K-AKT-mTORC1-Hif1a and c-myc/p19Arf pathways to suppress innate variant TFH cell development, thymocyte expansion, and lymphomagenesis.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genome-wide characterization of menin-dependent H3K4me3 reveals a specific role for menin in the regulation of genes implicated in MEN1-like tumors.
Specimen part
View SamplesInactivating mutations in the MEN1 gene predisposing to the multiple endocrine neoplasia type 1 (MEN1) syndrome can also cause sporadic pancreatic endocrine tumors. MEN1 encodes menin, a subunit of MLL1/MLL2-containing histone methyltransferase complexes that trimethylate histone H3 at lysine 4 (H3K4me3). The importance of menin-dependent H3K4me3 in normal and transformed pancreatic endocrine cells is unclear. To study the role of menin-dependent H3K4me3, we performed in vitro differentiation of wild-type as well as menin-null mouse embryonic stem cells (mESCs) into pancreatic islet-like endocrine cells (PILECs). Gene expression analysis and genome-wide H3K4me3 ChIP-Seq profiling in wild-type and menin-null mESCs and PILECs revealed menin-dependent H3K4me3 at the imprinted Dlk1-Meg3 locus in mESCs, and all four Hox loci in differentiated PILECs. Specific and significant loss of H3K4me3 and gene expression was observed for genes within the imprinted Dlk1-Meg3 locus in menin-null mESCs and the Hox loci in menin-null PILECs. Given that the reduced expression of genes within the DLK1-MEG3 locus and the HOX loci is associated with MEN1-like sporadic tumors, our data suggests a possible role for menin-dependent H3K4me3 at these genes in the initiation and progression of sporadic pancreatic endocrine tumors. Furthermore, our investigation also demonstrates that menin-null mESCs can be differentiated in vitro into islet-like endocrine cells, underscoring the utility of menin-null mESC-derived specialized cell types for genome-wide high-throughput studies.
Genome-wide characterization of menin-dependent H3K4me3 reveals a specific role for menin in the regulation of genes implicated in MEN1-like tumors.
Specimen part
View SamplesAcrylamide is a type-2 alkene monomer with established human neurotoxic effects. While the primary source of human exposure to acrylamide is occupational, other exposure sources include food, drinking water, and smoking. In this study, neurobehavioral assays coupled with transcriptional profiling analysis were conducted to assess both behavioral and gene expression effects induced by acrylamide neurotoxicity in rats when administered during early postnatal life. Acrylamide administration in rat pups induced significant characteristic neurotoxic symptoms including increased heel splay, decrease in grip strength, and decrease in locomotor activity. Transcriptome analysis with the Affymetrix Rat Genome 230 2.0 array indicated that acrylamide treatment caused a significant alteration in the expression of genes involved in muscle contraction, pain regulation, and dopaminergic neuronal pathways. First, in agreement with the observed behavioral effects, expression of the Mylpf gene involved in muscle contraction was downregulated in the spinal cord in response to acrylamide. Second, in sciatic nerves, acrylamide repressed the expression of the opioid receptor gene Oprk1 that is known to play a role in neuropathic pain regulation. Finally, in the cerebellum, acrylamide treatment caused a decrease in the expression of the nuclear receptor gene Nr4a2 that is required for development of dopaminergic neurons. Thus, our work examining the effect of acrylamide at the whole-genome level on a developmental mammalian model has identified novel genes previously not implicated in acrylamide neurotoxicity that can be further developed into biomarkers for assessing the risk of acrylamide exposure.
Neurobehavioral and transcriptional effects of acrylamide in juvenile rats.
Sex, Specimen part, Treatment
View SamplesThe recent reports of two circular RNAs (circRNAs) with strong potential to act as microRNA (miRNA) sponges suggest that circRNAs might play important roles in regulating gene expression. However, the global properties of circRNAs are not well understood. We developed a computational pipeline to identify circRNAs and quantify their relative abundance from RNA-seq data. Applying this pipeline to a large set of non-poly(A)-selected RNA-seq data from the ENCODE project, we annotated 7,112 human circRNAs that were estimated to comprise at least 10% of the transcripts accumulating from their loci. Most circRNAs are expressed in only a few cell types and at low abundance, but they are no more cell-type–specific than are mRNAs with similar overall expression levels. Although most circRNAs overlap protein-coding sequences, ribosome profiling provides no evidence for their translation. We also annotated 635 mouse circRNAs, and although 20% of them are orthologous to human circRNAs, the sequence conservation of these circRNA orthologs is no higher than that of their flanking linear exons. The previously proposed miR-7 sponge, CDR1as, is one of only two circRNAs with more miRNA sites than expected by chance, with the next best miRNA-sponge candidate deriving from a primate-specific zinc-finger gene, ZNF91. These results provide a new framework for future investigation of this intriguing topological isoform while raising doubts regarding a biological function of most circRNAs. Overall design: Examination of 9 samples in 1 cell type Note: The ENCODE data we used are under GEO SuperSeries GSE26284 (all samples labeled "_cell_total"). But they were not used in the processing of the U2OS data.
Expanded identification and characterization of mammalian circular RNAs.
No sample metadata fields
View SamplesMEN1 is a tumor suppressor gene loss of which causes lipoma (fatty tumors under the skin) and many other endocrine and non-endocrine tumors. It's target genes in fat cells (adipocytes) are unknown. Gene expression in adipocytes that were in vitro differentiated from mouse embryonic stem cells (mESCs) of Men1-nul l(Men1-KO) and WT mice were compared to assess the expression of genes upon menin loss in adipocytes that could lead to the deveopment of lipoma.
Consequence of Menin Deficiency in Mouse Adipocytes Derived by In Vitro Differentiation.
Specimen part
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