The Gata2 transcription factor is a pivotal regulator of hematopoietic stem cell (HSC) development and maintenance. Gata2 functions in the embryo during endothelial cell to hematopoietic cell transition (EHT) to affect hematopoietic cluster, HPC and HSC formation. Although previous studies of cell populations phenotypically enriched in HPCs and HSCs show expression of Gata2, there has been no direct study of Gata2 expressing cells during normal hematopoiesis. In this study we generate a Gata2 Venus reporter mouse model with unperturbed Gata2 expression to examine the hematopoietic function and transcriptome of Gata2 expressing and nonexpressing cells. Overall design: Gata2Venus- HPCs 1 replicate, Gata2Venus+ HPCs 1 replicate
Functional and molecular characterization of mouse Gata2-independent hematopoietic progenitors.
Specimen part, Cell line, Subject
View SamplesThe first HSCs are produced in the aorta-gonadmesonephros (AGM) region of the embryo through endothelial to a hematopoietic transition. BMP4 and Hedgehog affect their production/expansion, but it is unknown whether they act to affect the same HSCs. In this study using the BRE GFP reporter mouse strain that identifies BMP/Smad-activated cells, we find that the AGM harbors two types of adult-repopulating HSCs upon explant culture. Overall design: Embryonic day 11 AGM are dissected and either analyzed directly, or after explant culture in conditions containing BMP/Hedgehog with or without cyclopamine. EC: endothelial enriched (CD31+Kit-); MC: mesenchymal cell enriched (CD31-Kit-); HPSC: hematopoietic progenitor/stem cell enriched; AGM11: E11 fresh AGMs; AGMex: AGM after explant culture; AGMcy: AGM after explant in presence of cyclopamine; CD31p: CD31 positive; CD31n: CD31 negative; KITp: c-Kit positive; KITn: c-Kit negative; BREp: BRE-GFP positive; BREn: BRE-GFP negative
BMP and Hedgehog Regulate Distinct AGM Hematopoietic Stem Cells Ex Vivo.
Specimen part, Cell line, Subject
View SamplesHematopoietic stem cells (HSCs) are generated via a natural transdifferentiation process known as endothelial-to-hematopoietic cell transition (EHT). Due to small numbers of embryonal arterial cells undergoing EHT and the paucity of markers to enrich for hemogenic endothelial cells, the genetic program driving HSC emergence is largely unknown. Here, we use a highly sensitive RNAseq method to examine the whole transcriptome of small numbers of enriched aortic HSCs (CD31+cKit+Ly6aGFP+), hemogenic endothelial cells (CD31+cKit-Ly6aGFP+) and endothelial cells (CD31+cKit-Ly6aGFP-). Overall design: Comparison of mRNA profiles of endothelial cells, hemogenic endothelial cells, and hematopoietic stem cells generated by deep-sequencing of sorted populations from pool of embryos, in triplicate.
Whole-transcriptome analysis of endothelial to hematopoietic stem cell transition reveals a requirement for Gpr56 in HSC generation.
No sample metadata fields
View SamplesIt is well established that the expression profiles of multiple and possibly redundant matrix remodeling proteases (e.g. collagenases) strongly differ in health, disease and development. Although enzymatic redundancy might be inferred from their close similarity in structure, their in-vivo activity can lead to extremely diverse tissue-remodeling outcomes. We observed that proteolysis of collagen-rich natural extracellular matrix (ECM), generated uniquely by individual homologous proteases, leads to specific combinatorial events, which eventually affects overall ECM topography, visco-elastic properties and composition. We reveal striking differences in the movement and signaling patterns, morphology, and gene expression profiles of cells interacting with natural collagen-rich ECM degraded by different collagenases. Thus, unlike envisioned before matrix-remodeling systems are not redundant and give rise to precise ECM-cell crosstalk. As ECM proteolysis is an abundant biochemical process critical to tissue homoeostasis, these results improve our fundamental understanding of combinatorial factors dictating cell behavior. Overall design: We analyzed the transcriptional responses of fibroblasts interacting with MMP1 or MMP13-remodeled ECM 4 hours post seeding. Samples used: Fibroblasts interacting with MMP1-remodeled ECM; Fibroblasts interacting with MMP13-remodeled ECM; Control samples- Fibroblasts interacting with natural ECM. All samples were run in duplicates.
Distinct biological events generated by ECM proteolysis by two homologous collagenases.
No sample metadata fields
View SamplesPooling of microarray datasets seems to be a reasonable approach to increase sample size when a heterogeneous disease like breast cancer is concerned. Different methods for the adaption of datasets have been used in the literature. We have analyzed influences of these strategies using a pool of 3,030 Affymetrix U133A microarrays from breast cancer samples. We present data on the resulting concordance with biochemical assays of well known parameters and highlight critical pitfalls. We further propose a method for the inference of cutoff values directly from the data without prior knowledge of the true result. The cutoffs derived by this method displayed high specificity and sensitivity. Markers with a bimodal distribution like ER, PgR, and HER2 discriminate different biological subtypes of disease with distinct clinical courses. In contrast, markers displaying a continuous distribution like proliferation markers as Ki67 rather describe the composition of the mixture of cells in the tumor.
Data-driven derivation of cutoffs from a pool of 3,030 Affymetrix arrays to stratify distinct clinical types of breast cancer.
Sex, Specimen part
View SamplesTranscriptomic profiling of human breast tumors using RNA sequencing Overall design: Evaluation of common fusion transcripts, genetic variants, and gene expression patterns in 8p11-p12 amplified breast carcinomas
Genome-wide multi-omics profiling of the 8p11-p12 amplicon in breast carcinoma.
Age, Specimen part, Subject
View SamplesCurrent prognostic gene expression profiles for breast cancer mainly reflect proliferation status and are most useful in ER-positive cancers. Triple-negative breast cancers (TNBCs) are clinically heterogeneous, and prognostic markers and biology-based therapies are needed to better treat this disease.
A clinically relevant gene signature in triple negative and basal-like breast cancer.
Specimen part
View SamplesChanges in endothelial phenotype induced by E. coli-derived Shiga toxins (Stx) are believed to play a critical role in the pathogenesis of hemolytic uremic syndrome. Stx inactivate host ribosomes, but also alter gene expression at concentrations that minimally affect global protein synthesis. The effect of Stx on the gene expression profile of human microvascular endothelial cells was examined using the Affymetrix HG-U133A platform. Data were processed using 13 different methods and revealed 369 unique differentially expressed genes, 318 of which were up-regulated and 51 of which were down-regulated. These studies implicated activation of the CXCR4/CXCR7/SDF-1 chemokine pathway in Stx-mediated pathogenesis.
The CXCR4/CXCR7/SDF-1 pathway contributes to the pathogenesis of Shiga toxin-associated hemolytic uremic syndrome in humans and mice.
Sex
View SamplesDifferent combinations of Endoglin tissue specific enhancers define hemangioblast and hemogenic endothelium cell fractions Overall design: We generated a series of embryonic stem cell lines, each targeted with reporter constructs driven by tissue specific promoter/enhancer combinations of Endoglin (ENG). The Eng promoter (P) when combined with the -8/+7/+9kb enhancers targeted cells in FLK1 mesoderm that were enriched for blast colony forming potential, whereas the P/-8kb enhancer targeted TIE2+/c-KIT+/CD41- HE cells that were enriched for hematopoietic potential. These cell fractions were isolated and their transcriptomes profiled by RNA-seq.
Identification of novel regulators of developmental hematopoiesis using Endoglin regulatory elements as molecular probes.
Subject
View SamplesWe analyzed gene expression profiles of myeloma cells belonging to the group of bas prognosis RPMI 8226 and LP1 expressing either the GFP protein or a cyclin D1-GFP fusion protein
Cyclin D1 sensitizes myeloma cells to endoplasmic reticulum stress-mediated apoptosis by activating the unfolded protein response pathway.
Specimen part, Cell line
View Samples