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GSE38027
Homo sapiens
4 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Abstract. The role of platelets in hemostasis and thrombosis is clearly established; however, the mechanisms by which platelets mediate inflammatory and immune pathways are less well understood. Platelets interact and modulate the function of blood and vascular cells by releasing bioactive molecules. Although the platelet is anucleate, it contains transcripts that may mirror disease. Platelet mRNA is only associated with low-level protein translation, however, platelets have a unique membrane structure allowing for the passage of small molecules, leading to the possibility that its cytoplasmic RNA may be passed to nucleated cells. To examine this question, platelet-like particles with labeled RNA were co-cultured with vascular cells. Co-culture of platelet-like particles with activated THP-1, monocytic, and endothelial cells led to visual and functional RNA transfer. Post-transfer microarray gene expression analysis of THP-1 cells showed an increase in HBG1/HBG2 and HBA1/HBA2 expression which was directly related to the transfer. Infusion of wild-type platelets into a TLR2 deficient mouse model established in vivo confirmation of select platelet RNA transfer to leukocytes. By specifically transferring green fluorescent protein, it was also observed that external RNA was functional in the recipient cells. The observation that platelets possess the capacity to transfer cytosolic RNA suggests a new function for platelets in the regulation of vascular homeostasis.
Publication Title
Platelets and platelet-like particles mediate intercellular RNA transfer.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Cholecystokinin (CCK) is a satiety hormone produced by discrete enteroendocrine cells scattered among absorptive cells of the small intestine. CCK is released into blood following a meal; however, the mechanisms inducing hormone secretion are largely unknown. Ingested fat is the major stimulant of CCK secretion. We recently identified a novel member of the lipoprotein remnant receptor family known as immunoglobulin-like domain containing receptor 1 (ILDR1) in intestinal CCK cells and postulated that this receptor conveyed the signal for fat-stimulated CCK secretion. In the intestine, ILDR1 is expressed exclusively in CCK cells. Orogastric administration of fatty acids elevated blood levels of CCK in wild type but not ILDR1-deficient mice, although the CCK secretory response to trypsin inhibitor was retained. The uptake of fluorescently labeled lipoproteins in ILDR1-transfected CHO cells and release of CCK from isolated intestinal cells required a unique combination of fatty acid plus HDL. CCK secretion secondary to ILDR1 activation is associated with increased [Ca2+]i consistent with regulated hormone release. These findings demonstrate that ILDR1 regulates CCK release through a mechanism dependent on fatty acids and lipoproteins and that absorbed fatty acids regulate gastrointestinal hormone secretion.
Publication Title
Immunoglobulin-like domain containing receptor 1 mediates fat-stimulated cholecystokinin secretion.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
Illumina HiSeq 2000
Description
The Ets family transcription factor PU.1 is essential for the development and maintenance of several hematopoietic lineages. In the thymus, PU.1 is expressed only in the early ETP/DN1, DN2a and DN2b stages of development. While PU.1 deletion in multipotent precursors leads to a complete block in T-cell development its function in the intrathymic stages in which it is expressed remains undetermined. The goal of this expression profiling study was to determine if PU.1 regulates the expression of T-lineage genes during the early stages of development. To do this, we generated the PU.1-Eng construct which expresses a fusion protein containing the DNA binding ETS domain of PU.1 (aas 159-260) fused to the obligate repressor domain (aas 1-298) of the Drosophila engrailed protein. The PU.1-ETS construct only expresses the ETS domain of PU.1 (aas 159-260) and serves as a control. Fetal liver precursors were isolated from e14.5 embryos and co-cultured with OP9-DL1 cells in the presence of IL-7 and Flt3L (5 ng/ml each) for 4 days to obtain FLDN1, DN2a and DN2b cells. These were infected with vector only, PU.1-ETS and the PU.1-Eng constructs and DN2 cells were sorted after 20 hours of infection. Total RNA was isolated from these cells and polyA+ fraction was used to prepare libraries for high throughput sequencing. Libraries prepared from 2 independent sets of samples were subjected to non-strand specific single-end sequencing. Overall design: Two sets of samples generated from fetal liver precursor derived DN2 cells expressing PU.1-ETS and PU.1-Eng constructs were used for expression profiling. The LZRS retroviral vector, without any insert, was used to generate the vector control dataset.
Publication Title
Regulation of early T-lineage gene expression and developmental progression by the progenitor cell transcription factor PU.1.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 8 Downloadable Samples
- Affymetrix C. elegans Genome Array (celegans)
Description
We used gene expression profiling to address several specific questions that arose in a study of repair of ultraviolet C radiation in C elegans, as well as to generate hypotheses regarding the possible mechanism(s) of decreased DNA repair observed in old adults in that study. This analysis was performed in order to analyze gene expression in the strain (JK1107) and experimental conditions that we used for our DNA repair studies.
Publication Title
Decline of nucleotide excision repair capacity in aging Caenorhabditis elegans.
Sample Metadata Fields
No sample metadata fields
View Samples- Bos taurus
- 9 Downloadable Samples
- Affymetrix Bovine Genome Array (bovine)
Description
Yamoa is marketed and sold as a dietary supplement with anecdotal positive effects in asthma and hay fever. We determined that Yamoa (ground bark of Funtumia elastica tree) stimulated innate immunity in part by affecting gamma delta T cells. Yamoa had distinct priming effects, very similar to, but more robust than, that of lipopolysaccharide (LPS), on bovine, mouse and human gamma delta T cells. However, the optimal effect was dependent on the presence of accessory cells. Gene expression patterns in bovine gamma delta T cells and monocytes induced by Yamoa were very similar to those induced by ultrapure LPS, but the agonists in Yamoa did not signal entirely through TLR4. Yamoa stimulated human cells to produce cytokines involved innate protection. The bioactive component of Yamoa was delineated to a complex polysaccharide fraction (Yam-I). Intraperitoneal injection of Yamoa and very low doses of Yam-I in mice induced rapid increases peritoneal neutrophils directed by changes chemokine expression. Yamoa and Yam-I were effective as therapeutic treatments in mice with Salmonella enterica serotype Typhimurium (ST) induced enterocolitis that resulted in decreased bacterial counts in feces. This initial characterization of the immune stimulatory properties of polysaccharides derived from Yamoa suggests potential mechanisms for positive effects in asthma and that they have potential for application in infectious disease settings. .
Publication Title
Polysaccharides derived from Yamoa (Funtumia elastica) prime gammadelta T cells in vitro and enhance innate immune responses in vivo.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 90 Downloadable Samples
- Illumina HiSeq 2000
Description
During T cell development, multipotent progenitors relinquish competence for other fates and commit to the T cell lineage by turning on Bcl11b, which encodes a transcription factor. To clarify lineage commitment mechanisms, we followed developing T cells at the single-cell level using Bcl11b knock-in fluorescent reporter mice. Notch signaling and Notch activated transcription factors collaborate to activate Bcl11b expression irrespectively of Notch-dependent proliferation. These inputs work via three distinct, asynchronous mechanisms: an early locus ‘poising’ function dependent on TCF-1 and GATA-3, a stochastic-permissivity function dependent on Notch signaling, and a separate amplitude-control function dependent on Runx1, a factor already present in multipotent progenitors. Despite their necessity for Bcl11b activation, these inputs act in a stage specific manner, providing a multitiered mechanism for developmental gene regulation. Overall design: Two sets of samples were generated from DN T-cell sub-populations derived from culture of bone marrow progenitors from mice containing a knock-in Bcl11b-YFP reporter
Publication Title
Asynchronous combinatorial action of four regulatory factors activates Bcl11b for T cell commitment.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 14 Downloadable Samples
- Illumina HumanRef-8 v3.0 expression beadchip
Description
The molecular mechanisms underlying the development of bone metastases in breast cancer remain unclear. Disseminated tumour cells (DTCs) in the bone marrow of breast cancer patients are commonly identified, even in early stage disease, but their potential to initiate metastases is not known. The mechanism whereby DTCs become overt metastatic tumour cells (MTCs) is therefore, an area of considerable interest. This study explored the analysable yield of genetic material from human biopsy samples in order to describe differences in gene expression between DTCs and bone MTCs. Thirteen breast cancer patients with bone metastases underwent a CT-guided bone metastasis biopsy and a bone marrow biopsy. Tumour cells were enriched and gene expression profiling was conducted to identify differentially expressed genes. The analysable yield of sufficient RNA for microarray analysis was 60% from bone metastasis biopsies and 80% from bone marrow biopsies. A signature of 133 candidate genes differentially expressed between DTCs and MTCs was identified. Several genes relevant to breast cancer metastasis to bone (osteopontin, CTGF, parathyroid hormone receptor, EGFR) were significantly overexpressed in MTCs as compared to DTCs. Biopsies of bone metastases and bone marrow rarely yield enough tissue for robust molecular biology studies using clinical samples. The findings obtained however are interesting and seem to overlap with the bone metastasis gene expression signature described in murine xenograft models. Larger biopsy specimens or improved RNA extraction techniques may improve analysable yield and feasibility of these techniques.
Publication Title
Mechanisms and pathways of bone metastasis: challenges and pitfalls of performing molecular research on patient samples.
Sample Metadata Fields
Specimen part, Disease
View Samples- Homo sapiens
- 117 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Purpose: Gene expression signatures developed to measure the activity of oncogenic signaling pathways have been used to dissect the heterogeneity of tumor samples and to predict sensitivity to various cancer drugs that target components of the relevant pathways, thus potentially identifying therapeutic options for subgroups of patients. To facilitate broad use, including in a clinical setting, the ability to generate data from formalin-fixed, paraffin-embedded (FFPE) tissues is essential. Experimental Design: Patterns of pathway activity in matched fresh-frozen and FFPE xenograft tumor samples were generated using the MessageAmp Premier methodology in combination with assays using Affymetrix arrays. Results generated were compared with those obtained from fresh-frozen samples using a standard Affymetrix assay. In addition, gene expression data from patient matched fresh-frozen and FFPE melanomas were also utilized to evaluate the consistency of predictions of oncogenic signaling pathway status. Results: Significant correlation of pathway activity predictions was observed between paired fresh-frozen and FFPE xenograft tumor samples. In addition, significant concordance of pathway activity predictions was also observed between patient matched fresh-frozen and FFPE melanomas. Conclusion: Reliable and consistent predictions of oncogenic pathway activities can be obtained from FFPE tumor tissue samples. The ability to reliably utilize FFPE patient tumor tissue samples for genomic analyses will lead to a better understanding of the biology of disease progression and, in the clinical setting, will provide tools to guide the choice of therapeutics to those most likely to be effective in treating a patients disease.
Publication Title
A methodology for utilization of predictive genomic signatures in FFPE samples.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 7 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Different inflammatory stimuli contribute to the formation of atherosclerosis. It is hypothesized that although the end result is the same - plaque formation in arterial vessels - the pathogenesis is dependent on the etiology. In particular, platelets will respond differently depending on the inflammatory stimuli and timepoint.
Publication Title
Specific Inflammatory Stimuli Lead to Distinct Platelet Responses in Mice and Humans.
Sample Metadata Fields
Specimen part, Treatment, Time
View Samples- Homo sapiens
- 40 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Despite advances in contemporary chemotherapeutic strategies, long term survival still remains elusive for patients with metastatic colorectal cancer. A better understanding of the molecular markers of drug sensitivity to match therapy with patient is needed to improve clinical outcomes. In this study, we used in vitro drug sensitivity data from the NCI-60 cell lines together with their Affymetrix microarray data to develop a gene expression signature to predict sensitivity to oxaliplatin. In order to validate our oxaliplatin sensitivity signature, Patient-Derived Colorectal Cancer Explants (PDCCEs) were developed in NOD-SCID mice from resected human colorectal tumors. Analysis of gene expression profiles found similarities between the PDCCEs and their parental human tumors, suggesting their utility to study drug sensitivity in vivo. The oxaliplatin sensitivity signature was then validated in vivo with response data from 14 PDCCEs treated with oxaliplatin and was found to have an accuracy of 92.9% (Sensitivity=87.5%; Specificity=100%). Our findings suggest that PDCCEs can be a novel source to study drug sensitivity in colorectal cancer. Furthermore, genomic-based analysis has the potential to be incorporated into future strategies to optimize individual therapy for patients with metastatic colorectal cancer.
Publication Title
Characterization of an oxaliplatin sensitivity predictor in a preclinical murine model of colorectal cancer.
Sample Metadata Fields
No sample metadata fields
View Samples