Expression of meningioma 1 (MN1) has been proposed to be a negative prognostic molecular marker in adult AML with normal cytogenetics, however its role in pediatric leukemia is unknown. We found elevated MN1 expression in 53 of 88 pediatric leukemia cases: significant amounts of MN1 were found in immature B-cell ALL and most cases of infant leukemia but no MN1 expression was detected in T-cell acute lymphoblastic leukemia (T-ALL). Interestingly 17 of 19 cases harboring MLL-X fusions showed also elevated MN1 expression. Lentiviral siRNA mediated MN1 knock-down resulted in cell cycle arrest and impaired clonogenic growth of 3 MLL-X-positive human leukemia cell lines overexpressing MN1 (THP-1, RS4;11, MOLM13). In a mouse MLL/ENL-induced leukemia MN1 overexpression resulted from retroviral provirus insertion. Strikingly co-expression of MN1 with MLL/ENL resulted in significantly reduced latency for induction of an AML phenotype in mice suggesting functional cooperation. MN1 overexpression in MLL/ENL-carrying cells resulted in expansion of the L-GMP population and facilitated disease induction in secondary recipients. Gene expression profiling allowed to define a number of potential MN1 hematopoietic targets. Up-regulation of CD34, FLT3, HLF, or DLK1 was validated in bone marrow transiently overexpressing MN1, in MN1-induced mouse leukemias, as well as in some cases of pediatric leukemias overexpressing MN1. Taken together, our work suggests that MN1 overexpression is essential for growth of leukemic cells, and that MN1 can act as a cooperating oncogene with MLL-X fusion genes most probably through modification of a distinct gene expression program that leads to expansion of a leukemia initiating cell population.
Functional characterization of high levels of meningioma 1 as collaborating oncogene in acute leukemia.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
MLL-AF9 Expression in Hematopoietic Stem Cells Drives a Highly Invasive AML Expressing EMT-Related Genes Linked to Poor Outcome.
Specimen part
View SamplesTo address the impact of cellular origin on AML, we generated an inducible transgenic mouse model for MLL-AF9 driven leukemia. MLL-AF9 expression in long-term hematopoietic stem cells (LT-HSCs) in vitro resulted in unprecedented clonogenic growth and expression of genes involved in migration and invasion. In vivo, some LT-HSC-derived AMLs were particularly aggressive with extensive tissue infiltration, chemo-resistance and expression of genes related to epithelial-mesenchymal transition (EMT) in solid cancers. Knockdown of the EMT regulators Zeb1 and Tcf4 significantly reduced leukemic blast invasion. By classifying mouse and human leukemia according to Evi1/EVI1and Erg/ERG expression, reflecting aggressiveness and cell-of-origin and performing comparative transcriptomics we identified numerous EMT-related genes that were significantly associated with poor overall survival of AML patients. Overall design: RNA from FACS sorted bone marrow subpopulations was isolated, RNA-sequencing libraries were prepared and sequenced on an Illumina HiSeq 2000. Reads mapping to RefSeq transcripts were counted.
MLL-AF9 Expression in Hematopoietic Stem Cells Drives a Highly Invasive AML Expressing EMT-Related Genes Linked to Poor Outcome.
No sample metadata fields
View SamplesTo address the impact of cellular origin on AML, we generated an inducible transgenic mouse model for MLL-AF9 driven leukemia. MLL-AF9 expression in long-term hematopoietic stem cells (LT-HSCs) in vitro resulted in unprecedented clonogenic growth and expression of genes involved in migration and invasion. In vivo, some LT-HSC-derived AMLs were particularly aggressive with extensive tissue infiltration, chemo-resistance and expression of genes related to epithelial-mesenchymal transition (EMT) in solid cancers. Knockdown of the EMT regulators Zeb1 and Tcf4 significantly reduced leukemic blast invasion. By classifying mouse and human leukemia according to Evi1/EVI1and Erg/ERG expression, reflecting aggressiveness and cell-of-origin and performing comparative transcriptomics we identified numerous EMT-related genes that were significantly associated with poor overall survival of AML patients.
MLL-AF9 Expression in Hematopoietic Stem Cells Drives a Highly Invasive AML Expressing EMT-Related Genes Linked to Poor Outcome.
Specimen part
View SamplesWe investigated the nutritional effects on gene expression in sperm cells of F0 boars from a three generation Large White pig feeding experiment. A group of experimental (E) F0 boars were fed a standard diet supplemented with high amounts of methylating micronutrients whereas a control (C) group of F0 boars received a standard diet. These differentially fed F0 boars sired F1 boars which then sired 60 F2 pigs which were investigated in a previous study. The aim of this study was to investigate if the nutrition affects gene expression in sperm cells of differentially fed boars and thus carry information in the form of RNA molecules to the next generation. Four RNA samples from sperm cells of these differentially fed boars were analyzed by RNA-Seq methodology. We found no differential RNA expression in sperm cells of the two groups based on the adjusted P-value > 0.05. Nevertheless, we performed a pathway analysis with 105 genes that differed in gene expression on the level of nominal P-value < 0.05 between the two diet groups. We found a significant number of these differentially expressed genes were enriched for the pathway maps of bacterial infections in cystic fibrosis (CF) airways, glycolysis and gluconeogenesis p.3 and cell cycle_Initiation of mitosis. The GO processes including a significant portion of differentially expressed genes were viral transcription and viral genome expression, viral infectious cycle, cellular protein localization, cellular macromolecule localization, nuclear-transcribed mRNA catabolic process and nonsense-mediated decay. In summary, the results of the pathway analysis are also inconclusive and it is concluded that RNA expression in sperm cells is not significantly affected by extensive supplementation of methylating micronutrients. Consequently, RNA molecules could not be established as epigenetic marks in this feeding experiment. Overall design: Gene expression in sperm cells from differentially fed F0 boars was measured. F0 boars received either a standard diet or a standard diet supplemented with methylating micronutrients. These boars were used to study transgenerational epigenetic inheritance in a three generation pig pedigree. Therefore it was of interest if the diet affects gene expression in sperm cells which could then be transmitted to next generations.
In search of epigenetic marks in testes and sperm cells of differentially fed boars.
Sex, Specimen part, Subject
View SamplesInnate sensing of viruses by dendritic cells (DCs) is critical for the initiation of anti-viral adaptive immune responses. Virus, however, have evolved to suppress immune activation in infected cells. We now analyze the susceptibility of different populations of dendritic cells to viral infections. We find that circulating human CD1c+ DCs support infection by HIV and influenza virus. Viral infection of CD1c+ DCs is essential for virus-specific CD8+ T cell activation and cytosolic sensing of the virus. In contrast, circulating human CD141+ DCs and pDCs constitutively limit viral fusion. The small GTPase RAB15 mediates this differential viral resistance in DC subsets through selective expression in CD141+ DCs and pDCs. Therefore, dendritic cell sub-populations evolved constitutive resistance mechanisms to mitigate viral infection during induction of antiviral immune response. Overall design: Examination of transcriptional profiles in 4 DC subsets purified from 3 donors using RNASeq
Constitutive resistance to viral infection in human CD141<sup>+</sup> dendritic cells.
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View SamplesThe cellular response to DNA damage is mediated through multiple pathways that regulate and coordinate DNA repair, cell cycle arrest and cell death. We show that the DNA damage response (DDR) induced by ionizing radiation (IR) is coordinated in breast cancer cells by selective mRNA translation mediated by high levels of translation initiation factor eIF4G1. Increased expression of eIF4G1, common in breast cancers, was found to selectively increase translation of mRNAs involved in cell survival and the DDR, preventing autophagy and apoptosis (Survivin, HIF1, XIAP), promoting cell cycle arrest (GADD45a, p53, ATRIP, Chk1) and DNA repair (53BP1, BRCA1/2, PARP, Rfc2-5, ATM, MRE-11, others). Reduced expression of eIF4G1, but not its homolog eIF4G2, greatly sensitizes cells to DNA damage by IR, induces cell death by both apoptosis and autophagy, and significantly delays resolution of DNA damage foci with little reduction of overall protein synthesis. While some mRNAs selectively translated by higher levels of eIF4G1 were found to use internal ribosome entry site (IRES)-mediated alternate translation, most do not. The latter group shows significantly reduced dependence on eIF4E for translation, facilitated by an enhanced requirement for eIF4G1. Increased expression of eIF4G1 therefore promotes specialized translation of survival, growth arrest and DDR mRNAs that are important in cell survival and DNA repair following genotoxic DNA damage.
DNA damage and eIF4G1 in breast cancer cells reprogram translation for survival and DNA repair mRNAs.
Cell line
View SamplesMutations in the CLN3 gene lead to juvenile neuronal ceroid lipofuscinosis, a pediatric neurodegenerative disorder characterized by visual loss, epilepsy and psychomotor deterioration. Although most CLN3 patients carry the same 1 kb deletion in the CLN3 gene, their disease phenotype can be variable. The aims of this study were (1) to identify genes that are dysregulated in CLN3 disease regardless of the clinical course that could be useful as biomarkers, and (2) to find modifier genes that affect the progression rate of the disease.
Analysis of potential biomarkers and modifier genes affecting the clinical course of CLN3 disease.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesMucolipidosis type II (MLII) is a severe inherited multisystemic disorder caused by mutations in the GNPTAB gene. Skeletal abnormalities are a predominant feature of MLII. Here we investigate the gene expression in a knock-in mouse model for mucolipidosis type II, generated by the insertion of a cytosine in the murine Gnptab gene (c.3082insC) that is homologous to a homozygous mutation in an MLII patient.
Decreased bone formation and increased osteoclastogenesis cause bone loss in mucolipidosis II.
Specimen part
View SamplesPrevious results suggest that Bmh might inhibit the activity of the transcription factor Adr1 after binding to Adr1-dependent promoters. In a strain lacking the two major histone deacetylases, Hda1 and Rpd3 (hdac), Adr1 is bound to its target promoters recruiting what appears to be an inactive RNA ploymerase II preinitiation complex (PIC). To determine whether Bmh activity inhibits this inactive PIC and the generality of this effect on glucose-repressed gene expression, the mRNA profiles of wild type, bmh mutant, hdac mutant, and bmh hdac mutant cells grown in high glucose medium were compared.
14-3-3 (Bmh) proteins regulate combinatorial transcription following RNA polymerase II recruitment by binding at Adr1-dependent promoters in Saccharomyces cerevisiae.
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