Gene expression was examined in testis and brain tissue between two species (Xenopus laevis and Xenopus borealis) and their hybrid.
Single-species microarrays and comparative transcriptomics.
Age
View SamplesWe have derived hESC from biopsied blastomeres of cleavage stage embryos under virtually the same conditions we used for the derivation of hESC lines from inner cell mass of blastocyst stage embryos. Blastomere-derived hESC lines exhibited all the standard characteristics of hESC including undifferentiated proliferation, genomic stability, expression of pluripotency markers and the ability to differentiate into the cells of all three germ layers both in vitro and in vivo. To examine whether hESC lines derived from two developmental stages of the embryo differ in gene expression, we have subjected three blastomere-derived hESC lines and two ICM-derived hESC lines grown under identical culture conditions to transcriptome analysis using gene expression arrays. Unlike previously reported comparisons of hESC lines which demonstrated, apart from core hESC-associated pluripotency signature, significant variations in gene expression profiles of different lines, our data show that hESC lines derived and grown under well-controlled defined culture conditions adopt nearly identical gene expression profiles. Moreover, blastomere-derived and ICM-derived hESC exhibited very similar transcriptional profiles independent of the developmental stage of the embryo from which they originated. Furthermore, this profile was evident in very early passages of the cells and did not appear to be affected by extensive passaging. These results suggest that during derivation process cells which give rise to hESC acquire virtually identical stable phenotype and are not affected by the developmental stage of the starting cell population.
Human embryonic stem cells derived from embryos at different stages of development share similar transcription profiles.
Specimen part, Disease, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
PI3K-targeted therapy can be evaded by gene amplification along the MYC-eukaryotic translation initiation factor 4E (eIF4E) axis.
Specimen part
View SamplesGene expression signatures were measured after treatment of cells with 50nM BEZ235. Affymetrix HG-U133AV2 expression arrays were performed according to the manufacturer's directions using RNA extracted by Qiagen RNeasy from engineered human cell-lines grown for 72h in the presence of 50nM BEZ235
PI3K-targeted therapy can be evaded by gene amplification along the MYC-eukaryotic translation initiation factor 4E (eIF4E) axis.
Specimen part
View SamplesSubtypes of innate lymphoid cells (ILC), defined by effector function and transcription factor expression, have recently been identified. In the adult, ILC derive from common lymphoid progenitors in bone marrow, although transcriptional regulation of the developmental pathways involved remains poorly defined. TOX is required for development of lymphoid tissue inducer cells, a type of ILC3 required for lymph node organogenesis, and NK cells, a type of ILC1. We show here that production of multiple ILC lineages requires TOX, as a result of TOX-dependent development of common ILC progenitors. Comparative transcriptome analysis demonstrated failure to induce various aspects of the ILC gene program in the absence of TOX, implicating this nuclear factor as a key early determinant of ILC lineage specification. Overall design: TOX KO vs. wild tyype
The development of innate lymphoid cells requires TOX-dependent generation of a common innate lymphoid cell progenitor.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Effects of maternal obesity on Wharton's Jelly mesenchymal stromal cells.
Specimen part, Subject
View SamplesCirculating tumor cells (CTCs) are the subject of several translational studies and clinical trials because their examination could offer an insight into tumor progression and clinical outcomes. Circulating tumor microemboli (CTM) are clusters of CTCs that have been described as malignant entities for over 50 years, although a comprehensive characterization of these cells is still lacking. Contrary to current consensus, we demonstrate that CTM isolated from colorectal cancer patients are not cancerous, but represent a discrete population of tumor-derived endothelial cells. CTM express epithelial and mesenchymal markers that are consistent with previous reports on circulating tumor cell phenotyping. However, they do not mirror the genetic variations of matching tumors. Transcriptome analysis of single-CTM reveals that these structures exhibit an endothelial phenotype, with further results supporting a tumor-derived endothelial lineage. CTM are widespread in blood sampled from preoperative cancer patients but not in healthy donors, suggesting CTM count as a potential biomarker of interest for colorectal cancer. CTM should not be confused with bona fide circulating epithelial tumor cells. The characterization of tumor derived endothelial cell clusters (TECCs) is likely of high diagnostic value, and may provide direct information about the underlying tumor vasculature at the time of diagnosis, during treatment and the course of the disease. Overall design: Profiling of 18 TECCs/CTM from 8 colorectal cancer patients. In addition profiling of matched 7 normal colonic mucosa, 9 primary colorectal tumor samples (of which three from the same patient), one colorectal cancer metastatis. Additionally, 14 laser-capture-dissected endothelia from the same patients and tissues, and 3 commercially available normal endothelial cell lines
Tumor-derived circulating endothelial cell clusters in colorectal cancer.
No sample metadata fields
View SamplesMitochondrial DNA (mtDNA) mutations cause inherited diseases and are implicated in the pathogenesis of common late-onset disorders, but it is not clear how they arise and propagate in the humans. Here we show that mtDNA mutations are present in primordial germ cells (PGCs) within healthy female human embryos. Close scrutiny revealed the signature of selection against non-synonymous variants in the protein-coding region, tRNA gene variants, and variants in specific regions of the non-coding D-loop. In isolated single PGCs we saw a profound reduction in the cellular mtDNA content, with discrete mitochondria containing ~5 mtDNA molecules during early germline development. Single cell deep mtDNA sequencing showed rare variants reaching higher heteroplasmy levels in later PGCs, consistent with the observed genetic bottleneck, and predicting >80% levels within isolated organelles. Genome-wide RNA-seq showed a progressive upregulation of genes involving mtDNA replication and transcription, linked to a transition from glycolytic to oxidative metabolism. The metabolic shift exposes deleterious mutations to selection at the organellar level during early germ cell development. In this way, the genetic bottleneck prevents the relentless accumulation of mtDNA mutations in the human population predicted by Muller's ratchet. Mutations escaping this mechanism will, however, show massive shifts in heteroplasmy levels within one human generation, explaining the extreme phenotypic variation seen in human pedigrees with inherited mtDNA disorders. Overall design: RNA-Seq and NGS analysis to investigate transcriptomes and mtDNA sequences of fetal hPGCs
Segregation of mitochondrial DNA heteroplasmy through a developmental genetic bottleneck in human embryos.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Metabolomic Identification of Subtypes of Nonalcoholic Steatohepatitis.
Age, Specimen part, Treatment
View SamplesMethionine adenosyltransferase (MAT) enzymes generate SAMe (S-adenosylmethionine), the main biological methyl donor. There are two MAT encoding genes in mammals (Mat1a and Mat2a), which show different activities and cellular distribution. Mat1a encodes the enzyme mainly expressed in normal liver. Mat1a ablation in mice results in the spontaneous development of non-alcoholic steatohepatitis (NASH). We observed that SAMe depletion in Mat1a KO mice had three main effects on hepatic lipid metabolism: 1) impaired TG (triglyceride) export via VLDL; 2) impaired mitochondrial FA (fatty acid) oxidation (as evidenced by membrane depolarization, downregulation of Phb1 (prohibitin 1, a mitochondrial chaperone protein) and Mcj/Dnajc15 (endogenous mitochondrial repressor of respiratory chain), and accumulation of long-chain acylcarnitines); and 3) increased FA uptake. The convergence of these three factors induced TG accumulation in LD (lipid droplets). LD expansion confronts hepatocytes with a high demand of PC (phosphatidylcholine) molecules to cover the LD surface since other phospholipids, such as PE (phosphatidylethanolamine), cannot stabilize LD and prevent coalescence. In Mat1a KO this situation is aggravated, since SAMe-dependent PC synthesis via PE methylation is decreased, the PC/PE ratio reduced and mitochondrial FA oxidation impaired. To put a brake to this drain of PC molecules to LD, FA are rerouted in Mat1a KO mice liver to other catabolic (endoplasmic reticulum and peroxisome oxidation) and biosynthetic (ceramides synthesis) pathways, causing oxidative stress, inflammation and fibrosis. SAMe treatment for two months in 8-9 month old Mat1a KO mice ameliorated mitochondrial dysfunction (reduces membrane depolarization, improves Phb1 and Mcj expression, and increases SAMe transport to mitochondria) improving FA oxidation efficiency (FA and acylcarnitine levels decrease), which results in a drastic reduction in TG accumulation. SAMe treatment in Mat1a KO mice resulted in more PC available for proper membrane function, improving liver lipid homeostasis, histology (H&E, Sudan red, Sirius red) and liver injury (ALT, AST).
Metabolomic Identification of Subtypes of Nonalcoholic Steatohepatitis.
Age, Specimen part
View Samples