Radiotherapy is widely used to treat human cancer. Patients locally recurring after radiotherapy, however, have increased risk of metastatic progression and poor prognosis. The clinical management of post-radiation recurrences remains an unresolved issue. Tumors growing in pre-irradiated tissues have an increased fraction of hypoxic cells and are more metastatic, a condition known as tumor bed effect. Here we demonstrate that tumor cells growing in a pre-irradiated bed, or selected in vitro though repeated cycles of severe hypoxia, retain an invasive and metastatic capacities when returned to normoxia. HIF activity, while it facilitates metastatic spreading of tumors growing in a pre-irradiated bed, is not essential. Through gene expression profiling and gain and loss of function experiments, we identified the matricellular protein CYR61 and aVb5 integrin, as proteins cooperating to mediate these effects. Inhibition of aVb5 integrin suppressed invasion and metastasis induced by CYR61 and attenuated metastasis of tumors growing within a pre-irradiated field. These results represent a conceptual advance to the understanding of the tumor bed effect and identify CYR61 and aVb5 integrin as proteins that co-operate to mediate metastasis. They also indicate aV integrin inhibition a potential therapeutic approach for preventing metastasis in patients at risk for post-radiation recurrences, which can be promptly tested in the clinic.
CYR61 and alphaVbeta5 integrin cooperate to promote invasion and metastasis of tumors growing in preirradiated stroma.
No sample metadata fields
View SamplesWe report gene expression data for human melanoma cell lines using RNAseq. Overall design: RNAseq was performed on 8 melanoma cell lines and one normal human melanocyte cell line. All done as single replicates, except for two biological replicates of A375.
A zebrafish melanoma model reveals emergence of neural crest identity during melanoma initiation.
No sample metadata fields
View SamplesWe report gene expression data for FACS sorted zebrafish crestin_1kb:EGFP + cells collected at 15 somite stage (SS). Overall design: crestin_1kb:EGFP + embryos were homogenized, filtered, and sorted using FACS into PBS, collecting ~5,500 EGFP (+) cells and 100K EGFP (-) cells with a single sample for each.
A zebrafish melanoma model reveals emergence of neural crest identity during melanoma initiation.
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View SamplesCytokine-induced beta-cell apoptosis is a key event for the death of pancreatic beta cells in the development of type-1 diabetes. We identified BRD0476 as a novel suppressor of cytokine-induced beta-cell apoptosis.
Kinase-Independent Small-Molecule Inhibition of JAK-STAT Signaling.
Specimen part, Cell line, Time
View SamplesInsulin resistance in skeletal muscle is a key phenotype associated with type 2 diabetes (T2D) and is even present in offspring of diabetic parents. However, molecular mediators of insulin resistance remain unclear. We find that the top-ranking gene set in expression analysis of muscle from humans with T2D and normoglycemic insulin resistant subjects with parental family history (FH+) of T2D is increased expression of actin cytoskeleton genes regulated by serum response factor (SRF) and its coactivator MKL1. Furthermore, the SRF activator STARS is upregulated in FH+ and T2D and inversely correlated with insulin sensitivity. These patterns are recapitulated in insulin resistant mice, and linked to alterations in two other regulators of this pathway: reduced G-actin and increased nuclear localization of MKL1. Both genetic and pharmacologic manipulation of STARS/MKL1/SRF pathway significantly alter insulin action: 1) Overexpression of MKL1 or reduction in G-actin decreased insulin-stimulated Akt phosphorylation; 2) reduced STARS expression increased insulin signalling and glucose uptake, and 3) SRF inhibition by CCG-1423 reduced nuclear MKL1, improved glucose uptake, and improved glucose tolerance in insulin resistant mice in vivo. Thus, SRF pathway alterations are a signature of insulin resistance which may also contribute to T2D pathogenesis and be a novel therapeutic target.
Increased SRF transcriptional activity in human and mouse skeletal muscle is a signature of insulin resistance.
Sex, Age, Specimen part
View SamplesIn homeostasis of adult vertebrate tissues, stem cells are thought to self-renew by infrequent and asymmetric divisions that generate another stem cell daughter and a progenitor daughter cell committed to differentiate. This model is based largely on in vivo invertebrate or in vitro mammal studies. Here we examine the dynamic behaviour of adult hair follicle stem cells in their normal setting by employing mice with repressible H2B-GFP expression to track cell divisions and Cre inducible mice to perform long-term single cell lineage tracing. We provide direct evidence for the infrequent stem cell division model in intact tissue. Moreover, we find that differentiation of progenitor cells occurs at different times and tissue locations than self-renewal of stem cells. Distinct fates of differentiation or self-renewal are assigned to individual cells in a temporal-spatial manner. We propose that large clusters of tissue stem cells behave as populations, whose maintenance involves unidirectional daughter-cell fate decisions.
Distinct self-renewal and differentiation phases in the niche of infrequently dividing hair follicle stem cells.
Specimen part
View SamplesPurpose: Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. The goals of this study was to obtain the trasncriptome of DGCR8_KO mESCs to compare it with the transcriptome of WT mESCs (deposit separately). Overall design: mRNA profiles of DGCR8_KO mouse embryonic stem cells were generated by deep sequencing, in duplicate, using Illumina HiSeq2000.
Noncanonical function of DGCR8 controls mESC exit from pluripotency.
Specimen part, Cell line, Subject
View SamplesOvarian cancer patients are generally diagnosed at stage III/IV, when ascites is common. The volume of ascites positively correlates with the extent of metastasis and negatively with prognosis. Membrane GRP78, a stress-inducible endoplasmic reticulum chaperone which also appears on the plasma membrane (memGRP78) of aggressive cancers, plays a crucial role in the maintenance of embryonic stem cells. Our present study demonstrates that tumor cells isolated from ascites generated by epithelial ovarian cancer (ID8 cells) bearing mice have increased memGRP78 expression compared to ID8 cells in normal culture. We hypothesize that these ascites associated memGRP78+ cells are cancer stem-like cells (CSC) and memGRP78 is functionally important in CSCs. Supporting this hypothesis, we show that memGRP78+ cells isolated from ascites have increased sphere forming and tumor initiating abilities compared to memGRP78- cells. When the tumor microenvironment is recapitulated by adding ascites fluid to cell culture, ID8 cells express more memGRP78 and increased self-renewing ability compared to those cultured in medium alone. Moreover, compared to their counterparts cultured in normal medium, ID8 cells cultured in ascites, or isolated from ascites, show an increased expression of stem cell markers Sca-1, Snail and SOX9. Importantly, antibodies directed against the carboxy (COOH)-terminal domain of GRP78 significantly reduce the self-renewing ability of murine and human ovarian cancer cells pre-incubated with ascites, associated with a decreased phosphorylation of Akt and GSK3, and reduced level of the transcriptional factor Snail. Based on this data, we suggest that memGRP78 is a logical therapeutic target for late stage ovarian cancer.
Syngeneic Murine Ovarian Cancer Model Reveals That Ascites Enriches for Ovarian Cancer Stem-Like Cells Expressing Membrane GRP78.
Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Gene expression patterns related to osteogenic differentiation of bone marrow-derived mesenchymal stem cells during ex vivo expansion.
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View SamplesThe aim of this study was to describe the gene expression patterns related to the differentiation and mineralization of bone-forming cells, including activation and/or repression of osteogenic or non-osteogenic pathways, remodeling of cell architecture, cell adhesion, cell communication, and assembly of extracellular matrix. The study implied patient selection, tissue collection, isolation and culture of human marrow stromal cells (hMSC) and osteoblasts (hOB), and characterization of bone-forming cells. RNA samples were collected at defined time points, in order to understand the regulation of gene expression during the processes of cell differentiation/mineralization that occur during bone repair. Transcriptome analysis was performed by using the Affymetrix GeneChip microarray technology platform and GeneChip Human Genome U133 Plus 2.0 Array. Our results help to design a gene expression profile of bone-forming cells during specific steps of osteogenic differentiation. These findings offer an useful tool to monitor the behaviour of osteogenic precursors cultured in presence of exogenous stimuli, i.e. growth factors, or onto 3D scaffolds for bone engineering. Moreover, they can contribute to identify and clarify the role of new genes for a better understanding of the molecular mechanisms regulating osteogenesis.
Gene expression patterns related to osteogenic differentiation of bone marrow-derived mesenchymal stem cells during ex vivo expansion.
No sample metadata fields
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