Mitochondrial dysfunction has been directly or indirectly implicated in the pathogenesis of a number of neurodegenerative disorders including Parkinson's disease, Alzheimer's disease and Amyotrophic Lateral Sclerosis (ALS). We used exon-sentive microarrays to characterize the responses to different mitochondrial perturbations in cellular models. We examined human SH-SY5Y neuroblastoma cells treated with paraquat, a neurotoxic herbicide which both catalyzes the formation of reactive oxygen species (ROS) and induces mitochondrial damage in animal models, and SH-SY5Y cells stably expressing the mutant SOD1(G93A) protein, one of the genetic causes of ALS. We identified a common set of genes that have a deregulated transcription and alternative splicing in both models. Noticeably, pathway analysis revealed that the expression of a subset of genes involved in neuritogenesis and axon guidance is perturbed, suggesting that alterations of axonal function may descend directly from mitochondrial damage and be responsible for neurodegenerative conditions.
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Cell line
View SamplesWhole-genome profiling of SH-SY5Y cells was done on neuroblastoma SH-SY5Y stably transfected with cDNAs coding for SOD1WT or the mutant SOD1(G93A) protein.
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Cell line
View SamplesHuman SH-SY5Y neuroblastoma cells treated with paraquat, a neurotoxic herbicide which both catalyzes the formation of reactive oxygen species (ROS) and induces mitochondrial damage in animal models was profiled using Affimetrix Exon 1.0 ST GeneChips
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Cell line
View SamplesTeratoma formation is the gold standard assay for testing the capacity of human stem cells to differentiate into all embryonic germ layers. Although widely used, little effort has been made to transform this qualitative assay into a quantitative one. Using gene expression data from a wide variety of cells, we created a gene scorecard representing tissues from all three germ layers as well as an extraembryonic tissue. A calculated grade using this gene list successfully distinguishes pluripotent stem cell-initiated teratomas from malignant tumors, thereby translating cell potency into a quantitative measure. This new methodology, named TeratoScore, thus assesses the pluripotency of human cells, and is easily performed using an open-source code. The new teratoma database also allowed us to examine the gene expression differences between tumors with a diploid karyotype and those initiated by aneuploid cells. We found that while teratomas originating from aneuploid cells pass the TeratoScore benchmark for pluripotency, they exhibit aberrant gene expression congruent with human chromosomal syndromes (such as Down syndrome). This gene expression signature is significantly different from that of teratomas originating from diploid cells, particularly in central nervous system-specific genes, suggesting aberrant teratomas may be beneficial for in vivo disease modeling. Teratoma formation followed by TeratoScore analysis can rapidly assess cell potency and allows comparison between different pluripotent cell lines.
TeratoScore: Assessing the Differentiation Potential of Human Pluripotent Stem Cells by Quantitative Expression Analysis of Teratomas.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
LRH-1 governs vital transcriptional programs in endocrine-sensitive and -resistant breast cancer cells.
Specimen part, Cell line
View SamplesTumor characteristics are decisive in the determination of treatment strategy for breast cancer patients. Patients with estrogen receptor- (ER) positive breast cancer can benefit from long-term hormonal treatment. Nonetheless, the majority of patients will develop resistance to these therapies. Here, we investigated the role of the liver receptor homolog-1 (LRH-1, NR5A2) in anti-estrogen (AE) sensitive and resistant breast cancer cells. We identified genome-wide LRH-1 binding sites using ChIP-seq, uncovering preferential binding to regions distal to transcriptional start sites (TSS). We further characterized these LRH-1 binding sites by integrating overlapping layers of specific chromatin marks, revealing that many LRH-1 binding sites are active and could be involved in long-range enhancer-promoter looping. Combined with transcriptome analysis of LRH-1 depleted cells, these results show that LRH-1 regulates specific subsets of genes involved in cell proliferation in AE-sensitive and AE-resistant breast cancer cells. Furthermore, the LRH-1 transcriptional program is highly associated with signature of poor outcome breast cancer tumors in vivo. Herein report the genome-wide location and molecular function of LRH-1 in breast cancer cells and reveal its therapeutic potential for the treatment of breast cancers, notably for tumors resistant to treatments currently used in therapies.
LRH-1 governs vital transcriptional programs in endocrine-sensitive and -resistant breast cancer cells.
Specimen part, Cell line
View SamplesDown syndrome (DS) is the leading genetic cause of mental retardation and is caused by a third copy of human chromosome 21. The different pathologies of DS involve many tissues with a distinct array of neural phenotypes. Here we characterize new embryonic stem cell lines with DS (DS-ESCs), and focus on the neural aspects of the diease. Our results show that neural progenitor cells (NPCs) differentiated from five independent DS-ESC lines display increased apoptosis and down-regulation of forehead developmental genes. Analysis of differentially expressed genes suggested RUNX1 as a key transcription regulator in DS-NPCs. Using genome editing we were able to disrupt all three copies of RUNX1 in DS-ESCs, leading to down-regulation of several RUNX1 target developmental genes accompanied by reduced apoptosis and neuron migration. Our work sheds new light on the role of RUNX1 and the importance of dosage balance in the development of neural phenotypes in DS.
Molecular Characterization of Down Syndrome Embryonic Stem Cells Reveals a Role for RUNX1 in Neural Differentiation.
Sex, Specimen part
View SamplesTumors driven by activation of the transcription factor Myc generally show oncogene addiction. However, the gene-expression programs that depend upon sustained Myc activity in those tumors remain unknown. We have addressed this issue in a model of liver carcinoma driven by a reversible tet-Myc transgene, combining gene expression profiling with the mapping of Myc and RNA Polymerase II on chromatin. Switching off the oncogene in advanced carcinomas revealed that Myc is required for the continuous activation and repression of distinct sets of genes, constituting no more than half of those deregulated during tumor progression, and an even smaller subset of all Myc-bound genes. We further showed that a Myc mutant unable to associate with the co-repressor protein Miz1 is defective in the initiation of liver tumorigenesis. Altogether, our data provide the first detailed analysis of a Myc-dependent transcriptional program in a fully developed carcinoma, revealing that the critical effectors of Myc in tumor maintenance must be included within defined subsets (ca. 1,300 each) of activated and repressed genes. Overall design: RNAseq samples of control liver (n=11), tet-Myc tumors (n=16), tet-Myc tumors with short-term Myc inactivation (n=8), tet-MycVD tumors (n=11)
Identification of MYC-Dependent Transcriptional Programs in Oncogene-Addicted Liver Tumors.
Specimen part, Cell line, Subject
View SamplesGenome-wide profiling establishes that human cytomegalovirus (HCMV) exerts an extensive, unforeseen level of specific control over which cellular mRNAs are recruited to or excluded from polyribosomes.
Global reprogramming of the cellular translational landscape facilitates cytomegalovirus replication.
Specimen part, Disease, Treatment
View SamplesRole of beta-arrestin2 in response to intermittent or continuous parathyroid hormone (PTH) treatment.
Beta-arrestin2 regulates parathyroid hormone effects on a p38 MAPK and NFkappaB gene expression network in osteoblasts.
Sex, Age, Specimen part, Disease, Compound
View Samples