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GSE41313
Homo sapiens
152 Downloadable Samples
Affymetrix HT HG-U133+ PM Array Plate (hthgu133pluspm)
Description
Breast cancer is a genetically and phenotypically complex disease. To understand the role of microRNAs in this molecular complexity, we performed miRNA expression analysis in a cohort of molecularly well-characterized human breast cancer (BC) cell lines to discover miRNAs associated with the most common molecular subtypes and the most frequent genetic aberrations.Using a microarray carrying LNA modified oligonucleotide capture probes (Exiqon), expression levels of 725 human miRNAs were measured in 51 BC cell lines. MiRNA expression was explored by unsupervised cluster analysis and then associated with the molecular subtypes and genetic aberrations commonly present in breast cancer. Unsupervised cluster analysis using the most variably expressed miRNAs divided the 51 BC cell lines into a major and a minor cluster predominantly mirroring the luminal and basal intrinsic subdivision of BC cell lines. One hundred and thirteen miRNAs were differentially expressed between these two main clusters of which half were related to the ER-status of the cell lines. Forty miRNAs were differentially expressed between basal-like and normal-like/claudin-low cell lines. Within the luminal-group of cell lines, 39 miRNAs were associated with ERBB2 overexpression and 24 miRNAs with E-cadherin gene mutations, which are frequent in this subtype of BC cell lines. In contrast, 31 different miRNAs were associated with E-cadherin promoter hypermethylation, which, contrary to E-cadherin mutation, is exclusively observed in BC cell lines that are not of luminal origin. The differential expression of 30 miRNAs were associated with p16INK4 status while only a few differentially expressed miRNAs were associated with BRCA1, or PIK3CA/PTEN, TP53 mutation status of the cell lines (P-value < 0.05). Twelve miRNAs were associated with DNA copy number variation of the respective locus. Luminal-basal and epithelial-mesenchymal associated miRNAs determine the overall subdivision of miRNA transcriptome of BC cell lines. Specific sets of miRNAs were associated with ERBB2 overexpression, p16INK4aor E-cadherin mutation or E-cadherin methylation status, which implies that these miRNAs may contribute to the driver role of the genetic aberrations. Additionally, miRNAs, which are located in a genomic region showing recurrent genetic aberrations, may themselves play a driver role in breast carcinogenesis or contribute to a driver gene in their vicinity. In short, our study provides detailed molecular miRNA portraits of BC cell lines, which can be exploited for functional studies of clinically important miRNAs.
Publication Title
miRNA expression profiling of 51 human breast cancer cell lines reveals subtype and driver mutation-specific miRNAs.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 5 Downloadable Samples
Description
In MLL-rearranged (MLLr) leukemias the N terminal part of the MLL gene can be fused to over 60 different partner genes. Here, we investigate the genome wide binding of the MLL-AF9 and MLL-AF4 fusion proteins and their epigenetic signatures in order to define a core set of MLLr targets. We uncover both common as well as specific MLL-AF9 and MLL-AF4 target genes, which are all marked by H3K79me2, H3K27ac, and H3K4me3. Apart from promoter binding, we also identify MLL-AF9 and MLL-AF4 binding at specific subsets of non overlapping active distal regulatory elements. Despite this differential enhancer binding MLL-AF9 and MLL-AF4 still share a common gene program, which represents part of the RUNX1 gene program and constitutes of CD34+ and monocyte specific genes. Comparing these datasets revealed several zinc finger transcription factors as potential MLL-AF9 co-regulators. Together these results suggest that MLL-fusions collaborate with specific subsets of TFs to aberrantly regulate the RUNX1 gene program in 11q23 AMLs. Overall design: Genome-wide (ChIP-seq) binding of MLL, AF9, AF4, H3K4me3, H3K27ac, H3K79me2 and RUNX1 in THP-1 and MV4-11 AML cell lines. Expression Profiling (RNA-seq) of THP-1 and MV4-11 cell lines, as well as 5 MLL-AF9 positive patient blasts.
Publication Title
MLL-AF9 and MLL-AF4 oncofusion proteins bind a distinct enhancer repertoire and target the RUNX1 program in 11q23 acute myeloid leukemia.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 20 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Medium-chain acyl-coenzyme A (CoA) dehydrogenase (MCAD) catalyzes crucial steps in mitochondrial fatty acid oxidation, a process that is of key relevance for maintenance of energy homeostasis, especially during high metabolic demand. To gain insight into the metabolic consequences of MCAD deficiency under these conditions, we compared hepatic carbohydrate metabolism in vivo in wild-type and MCAD-/- mice during fasting and during a lipopolysaccharide (LPS)-induced acute phase response (APR). MCAD-/- mice did not become more hypoglycemic on fasting or during the APR than wild-type mice did. Nevertheless, microarray analyses revealed increased hepatic peroxisome proliferator-activated receptor gamma coactivator-1a (Pgc-1a) and decreased peroxisome proliferator-activated receptor alpha (Ppar a) and pyruvate dehydrogenase kinase 4 (Pdk4) expression in MCAD-/- mice in both conditions,suggesting altered control of hepatic glucose metabolism. Quantitative flux measurements revealed that the de novo synthesis of glucose-6-phosphate (G6P) was not affected on fasting in MCAD-/- mice. During the APR, however, this flux was significantly decreased (-20%) in MCAD-/- mice compared with wild-type mice. Remarkably, newly formed G6P was preferentially directed toward glycogen in MCAD-/- mice under both conditions. Together with diminished de novo synthesis of G6P, this led to a decreased hepatic glucose output during the APR in MCAD-/- mice; de novo synthesis of G6P and hepatic glucose output were maintained in wild-type mice under both conditions. APR-associated hypoglycemia, which was observed in wild-type mice as well as MCAD-/- mice, was mainly due to enhanced peripheral glucose uptake. Conclusion: Our data demonstrate that MCAD deficiency in mice leads to specific changes in hepatic carbohydrate management on exposure to metabolic stress. This deficiency, however, does not lead to reduced de novo synthesis of G6P during fasting alone, which may be due to the existence of compensatory mechanisms or limited rate control of MCAD in murine mitochondrial fatty acid oxidation.
Publication Title
Disturbed hepatic carbohydrate management during high metabolic demand in medium-chain acyl-CoA dehydrogenase (MCAD)-deficient mice.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Homo sapiens
- 31 Downloadable Samples
- NextSeq 500
Description
To assess in vitro derived podocytes, we examined the transcriptional changes during human podocyte development and applied that knowledge to pinpoint strengths and limitations of hESC-derived podocytes. Overall design: We performed transcriptionaling profiling of kidney organoids and organoid-derived MAFB-eGFP+ podocytes at various differentiation time points.
Publication Title
In Vivo Developmental Trajectories of Human Podocyte Inform In Vitro Differentiation of Pluripotent Stem Cell-Derived Podocytes.
Sample Metadata Fields
Subject
View Samples- Caenorhabditis elegans
- 30 Downloadable Samples
- Illumina HiSeq 2000
Description
HIV-1 nucleoside reverse transcriptase inhibitor (NRTI) use is associated with severe adverse events. However, the exact mechanisms behind their toxicity has not been fully understood. Mitochondrial dysfunction after chronic exposure to NRTIs has predominantly been assigned to mitochondrial polymerase-? inhibition by NRTIs. However, an increasing amount of data suggests that this is not the sole mechanism. Many NRTI induced adverse events have been linked to the incurrence of oxidative stress, although the causality of events leading to reactive oxygen species (ROS) production and their role in toxicity is unclear. In this study we show that short-term effects of these drugs, which are rarely discussed in the literature, include direct inhibition of the mitochondrial respiratory chain (MRC), decreased ATP levels and increased ROS production. Collectively these events affect fitness and longevity of C. elegans through mitohormetic signalling events. Furthermore, we demonstrate that these effects can be normalized by addition of the anti-oxidant N-acetylcysteine (NAC), which suggests that ROS likely influence the onset and severity of adverse events upon drug exposure. Overall design: RNA-seq on Caenorhabditis elegans exposed to DMSO, 3''-azido-3''-deoxythymidine (zidovudine or AZT), 2'',3''-didehydro-2'',3''-deoxythymidine (stavudine or d4T), 3''-deoxy-3''-fluorothymidine (alovudine or FLT) or untreated control after 24 or 72 hours of exposure.
Publication Title
Beyond the polymerase-γ theory: Production of ROS as a mode of NRTI-induced mitochondrial toxicity.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 12 Downloadable Samples
- NextSeq 500
Description
In order to characterize and benchmark the podocytes-like cells generated through human ES cell differentiation, we generated transcriptional profiles of renal corpuscles from embryonic human kidneys using RNA-Seq. To compare, we also performed RNA-Seq of human immortalized podocyte cell lines before and after thermoswitch. Overall design: We performed RNA-Seq of poly-A selected RNA from hESC-derived kidney organoids, organoid-derived MAFB-eGFP+ podocytes at different time points, and human immortalized podocytes.
Publication Title
In Vivo Developmental Trajectories of Human Podocyte Inform In Vitro Differentiation of Pluripotent Stem Cell-Derived Podocytes.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 42 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
Aberrant splice variants are involved in the initiation and/or progression of glial brain tumors. We therefore set out to identify splice variants that are differentially expressed between histological subgroups of gliomas. Splice variants were identified using a novel platform that profiles the expression of virtually all known and predicted exons present in the human genome. Exon-level expression profiling was performed on 26 glioblastomas, 22 oligodendrogliomas and 6 control brain samples. Our results demonstrate that Human Exon arrays can identify subgroups of gliomas based on their histological appearance and genetic aberrations. We next used our expression data to identify differentially expressed splice variants. In two independent approaches, we identified 49 and up to 459 exons that are differentially spliced between glioblastomas and oligodendrogliomas a subset of which (47% and 33%) were confirmed by RT-PCR. In addition, exon-level expression profiling also identified >700 novel exons. Expression of ~67% of these candidate novel exons was confirmed by RT-PCR. Our results indicate that exon-level expression profiling can be used to molecularly classify brain tumor subgroups, can identify differentially regulated splice variants and can identify novel exons. The splice variants identified by exon-level expression profiling may help to detect the genetic changes that cause or maintain gliomas and may serve as novel treatment targets.
Publication Title
Identification of differentially regulated splice variants and novel exons in glial brain tumors using exon expression arrays.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 70 Downloadable Samples
- Illumina HiSeq 2000
Description
Organisms have adapted to the changing environmental conditions within the 24h cycle of the day by temporally segregating tissue physiology to the optimal time of the day. On the cellular level temporal segregation of physiological processes is established by the circadian clock, a Bmal1 dependent transcriptional oscillator network. The circadian clocks within individual cells of a tissue are synchronised by environmental signals, mainly light, in order to reach temporally segregated physiology on the tissue level. However, how light mediated synchronisation of peripheral tissue clocks is achieved mechanistically and whether circadian clocks in different organs are autonomous or interact with each other to achieve rhythmicity is unknown. Here we report that light can synchronise core circadian clocks in two peripheral tissues, the epidermis and liver hepatocytes, even in the complete absence of functional clocks in any other tissue within the whole organism. On the other hand, tissue extrinsic circadian clock rhythmicity is necessary to retain rhythmicity of the epidermal clock in the absence of light, proving for the first time that the circadian clockwork acts as a memory of time for the synchronisation of peripheral clocks in the absence of external entrainment signals. Furthermore, we find that tissue intrinsic Bmal1 is an important regulator of the epidermal differentiation process whose deregulation leads to a premature aging like phenotype of the epidermis. Thus, our results establish a new model for the segregation of peripheral tissue physiology whereby the synchronisation of peripheral clocks is acquired by the interaction of a light dependent but circadian clock independent pathway with circadian clockwork dependent cues. Overall design: Determining the epidermal circadian transcriptome in the presence or absence of non-epidermal clocks after 6-7 days in complete darkness (DD).
Publication Title
BMAL1-Driven Tissue Clocks Respond Independently to Light to Maintain Homeostasis.
Sample Metadata Fields
Age, Specimen part, Cell line, Subject
View Samples- Mus musculus
- 72 Downloadable Samples
- Illumina HiSeq 2000
Description
Organisms have adapted to the changing environmental conditions within the 24h cycle of the day by temporally segregating tissue physiology to the optimal time of the day. On the cellular level temporal segregation of physiological processes is established by the circadian clock, a Bmal1 dependent transcriptional oscillator network. The circadian clocks within individual cells of a tissue are synchronised by environmental signals, mainly light, in order to reach temporally segregated physiology on the tissue level. However, how light mediated synchronisation of peripheral tissue clocks is achieved mechanistically and whether circadian clocks in different organs are autonomous or interact with each other to achieve rhythmicity is unknown. Here we report that light can synchronise core circadian clocks in two peripheral tissues, the epidermis and liver hepatocytes, even in the complete absence of functional clocks in any other tissue within the whole organism. On the other hand, tissue extrinsic circadian clock rhythmicity is necessary to retain rhythmicity of the epidermal clock in the absence of light, proving for the first time that the circadian clockwork acts as a memory of time for the synchronisation of peripheral clocks in the absence of external entrainment signals. Furthermore, we find that tissue intrinsic Bmal1 is an important regulator of the epidermal differentiation process whose deregulation leads to a premature aging like phenotype of the epidermis. Thus, our results establish a new model for the segregation of peripheral tissue physiology whereby the synchronisation of peripheral clocks is acquired by the interaction of a light dependent but circadian clock independent pathway with circadian clockwork dependent cues. Overall design: Determining the epidermal circadian transcriptome in the presence or absence of non-epidermal clocks under light entrainment (LD).
Publication Title
BMAL1-Driven Tissue Clocks Respond Independently to Light to Maintain Homeostasis.
Sample Metadata Fields
Age, Specimen part, Cell line, Subject
View Samples- Mus musculus
- 41 Downloadable Samples
- Affymetrix Mouse Gene 1.1 ST Array (mogene11st)
Description
Diminishment of colonic health is associated with various age-related pathologies. Calorie restriction (CR) is an efficient strategy to increase healthy lifespan, although underlying mechanisms are not fully elucidated. Here we report the effects of lifelong CR on markers of colonic health in aging mice. We show that 30% energy reduction, as compared to a control (C) and moderate-fat (MF) diet, is associated with attenuated immune-related gene expression and lower levels of bile acids in the colon. Pronounced shifts in microbiota composition, together with lowered plasma levels of interleukin 6, in mice exposed to CR are in line with these findings. Furthermore, expression of genes involved in lipid metabolism was higher upon CR as compared to C and MF, pointing towards efficient regulation of energy metabolism. Switching from CR to an ad libitum MF diet at old age revealed remarkable phenotypic plasticity, although expression of a small subset of genes remained CR-associated. This research demonstrates that CR beneficially affects markers of colonic health in aging mice and as such may attenuate the progressive age-related decline in health.
Publication Title
Lifelong calorie restriction affects indicators of colonic health in aging C57Bl/6J mice.
Sample Metadata Fields
Sex, Specimen part
View Samples