This SuperSeries is composed of the SubSeries listed below.
Stability of gene expression and epigenetic profiles highlights the utility of patient-derived paediatric acute lymphoblastic leukaemia xenografts for investigating molecular mechanisms of drug resistance.
Sex
View SamplesBackground: Patient-derived tumour xenografts are an attractive model for preclinical testing of anti-cancer drugs. Insights into tumour biology and biomarkers predictive of responses to chemotherapeutic drugs can also be gained from investigating xenograft models. As a first step towards examining the equivalence of epigenetic profiles between xenografts and primary tumours in paediatric leukaemia, we performed genome-scale DNA methylation and gene expression profiling on a panel of 10 paediatric B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) tumours that were stratified by prednisolone response. Results: We found high correlations in DNA methylation and gene expression profiles between matching primary and xenograft tumour samples with Pearsons correlation coefficients ranging between 0.85 and 0.98. In order to demonstrate the potential utility of epigenetic analyses in BCPALL xenografts, we identified DNA methylation biomarkers that correlated with prednisolone responsiveness of the original tumour samples. Differential methylation of CAPS2, ARHGAP21, ARX and HOXB6 were confirmed by locus specific analysis. We identified 20 genes showing an inverse relationship between DNA methylation and gene expression in association with prednisolone response. Pathway analysis of these genes implicated apoptosis, cell signalling and cell structure networks in prednisolone responsiveness. Conclusions: The findings of this study confirm the stability of epigenetic and gene expression profiles of paediatric BCP-ALL propagated in mouse xenograft models. Further, our preliminary investigation of prednisolone sensitivity highlights the utility of mouse xenograft models for preclinical development of novel drug regimens with parallel investigation of underlying gene expression and epigenetic responses associated with novel drug responses.
Stability of gene expression and epigenetic profiles highlights the utility of patient-derived paediatric acute lymphoblastic leukaemia xenografts for investigating molecular mechanisms of drug resistance.
Sex
View SamplesHere we studied the epigenetic regulation of the naïve CD4+ T-cell activation response among children with IgE-mediated food allergy. Using integrated DNA methylation and transcriptomic profiling, we found that food allergy in infancy is associated with dysregulation of T-cell activation genes. Reduced expression of cell cycle related targets of the E2F and MYC transcription factor networks, and remodeling of DNA methylation at metabolic (RPTOR, PIK3D, MAPK1, FOXO1) and inflammatory genes (IL1R, IL18RAP, CD82) were associated with poorer T-lymphoproliferative responses in infancy after polyclonal activation of the T-cell receptor. Overall design: mRNA sequencing of naïve CD4+ T-cells under two conditions (anti-CD3+CD28 activated, or quiescent) at two ages (baseline (12months) and followup (2 or 4 years)) in allergic and non-allergic children.
Epigenetic dysregulation of naive CD4+ T-cell activation genes in childhood food allergy.
Sex, Subject
View SamplesWe performed genome-wide methylation analysis of primary feto-placental arterial and venous endothelial cells from healthy (AEC and VEC) and GDM complicated pregnancies (dAEC and dVEC). Parallel transcriptome analysis identified variation in gene expression linked to GDM-associated DNA methylation, implying a direct functional link. Pathway analysis found that genes altered by exposure to GDM clustered to functions associated with Cell Morphology and Cellular Movement in both AEC and VEC. Further functional analysis demonstrated that GDM exposed cells have altered actin organization and barrier function.
Human fetoplacental arterial and venous endothelial cells are differentially programmed by gestational diabetes mellitus, resulting in cell-specific barrier function changes.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrated genomic analysis of relapsed childhood acute lymphoblastic leukemia reveals therapeutic strategies.
Specimen part, Disease
View SamplesThere is a distinct signature of differentially expressed probes from diagnosis to relapse
Integrated genomic analysis of relapsed childhood acute lymphoblastic leukemia reveals therapeutic strategies.
Specimen part, Disease
View SamplesThe production of definitive haematopoietic stem/progenitor cells from human pluripotent stem cells (hPSCs) remains a significant challenge. Using reporter lines to track the endothelial (SOX17) to haematopoietic (RUNX1C) transition, we found that hPSC differentiated in growth factor supplemented serum free medium generated RUNX1C+CD34+ clonogenic cells that homed to the bone marrow, but did not engraft. Compared to repopulation-competent cord blood CD34+ cells, RUNX1C+CD34+ progenitors lacked HOXA gene expression, indicating incorrect mesoderm patterning. This deficiency was ameliorated by a timed pulse of WNT activation combined with ACTIVIN antagonism. Significantly, these HOXA+ cultures now formed complex SOX17+ vessels that produced fetal liver-like haematopoietic cells, similar to the human aorta-gonad-mesonephros (AGM). Comparison of transcriptional profiles of these nascent haematopoietic stem/progenitors with cells isolated from human AGM confirmed significant similarities, consistent with the assignment of our in vitro generated cells to the definitive human haematopoietic lineage. Our findings argue that HOXA codes established early in differentiation predict cellular potential and provide correct cell patterning for the specification of definitive haematopoietic lineages from hPSCs. Overall design: mRNA profiles of 26 samples were obtained for 5 different cell populations and 2 different treatments.
Differentiation of human embryonic stem cells to HOXA<sup>+</sup> hemogenic vasculature that resembles the aorta-gonad-mesonephros.
Treatment, Subject
View SamplesThe goal of this study was to determine the effects of a well-characterized anti-androgen, abiraterone acetate, and a suspected human anti-androgen, di-n-butyl phthalate (DBP) on the androgenic function of human fetal testis. Human fetal testis was xenografted into the renal subcapsular space of castrated male athymic nude mice. Hosts were treated with hCG to stimulate testosterone production in the xenografts, and were concurrently treated with either abiraterone acetate or DBP. While abiraterone acetate (14 d, 75 mg/kg/d p.o.) dramatically reduced testosterone and the weights of androgen-sensitive host organs, DBP (14 d, 500 mg/kg/d p.o.) had no effect on androgenic endpoints.
Differential response to abiraterone acetate and di-n-butyl phthalate in an androgen-sensitive human fetal testis xenograft bioassay.
Specimen part
View SamplesTo determine gene expression changes during in vitro senescence of MSC we have analyzed differential expression of the corresponding early passage (P2) and senescent passage (PX). There were global changes in the gene expression profile that were reproducible in three independent donor samples.
Replicative senescence of mesenchymal stem cells: a continuous and organized process.
No sample metadata fields
View SamplesSmall intestinal bacterial overgrowth (SIBO) has been implicated in symptoms associated with functional gastrointestinal disorders (FGIDs), though mechanisms remain poorly defined and treatment involves non-specific antibiotics. Here we show that SIBO based on duodenal aspirate. culture reflects an overgrowth of anaerobes, does not correspond with patient symptoms, and may be a result of dietary preferences. Small intestinal microbial composition, on the other hand, is significantly altered in symptomatic patients and does not correspond with aspirate culture results. In a pilot interventional study we found that switching from a high fiber diet to a low fiber, high simple sugar diet triggered FGID-related symptoms and decreased small-intestinal microbial diversity and small-intestinal permeability. Our findings demonstrate that characterizing small intestinal microbiomes in patients with gastrointestinal symptoms may allow a more targeted antibacterial or a diet-based approach to treatment. Overall design: A host duodenal RNA sequencing study in conjuction with a microbial analysis of small bowel aspirates following dietary intervention to reduce fiber intake for 1 week. Aspirates were collected during research endoscopy and submtttied for for 16S microbial identification (european
Small intestinal microbial dysbiosis underlies symptoms associated with functional gastrointestinal disorders.
Sex, Age, Specimen part, Disease stage, Subject, Time
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