Six1 is a developmental transcriptional regulator frequently overexpressed in human tumors. Recent results also show that SIX1 acts as a repressor of cell senescence, an antiproliferative response with key roles in tumor suppression, among other physiological and pathological settings. Here, we set to study the impact of SIX1 gain of function in transformation and tumorigenesis of fibroblasts, in connection with senescence. Using transcriptomic, histological, and functional analyses in murine cells and tumors of fibroblast origin, we show that SIX1 has a strong pro-tumorigenic action in this model, linked to the repression of a senescence-related gene signature and the activation of cellular plasticity, mediated at least in part by direct transcriptional regulation of the stemness factor Sox2. Moreover, functional analyses with human glioma cell lines also show that SIX1 controls SOX2 expression, senescence and self-renewal in this model. Collectively, our results support a general link of SIX1 with senescence and SOX2-mediated cell plasticity in tumors. Overall design: mRNA profiles were obtained from SIX1-overexpressing tumors and controls in triplicate by RNA-Seq using Illumina HiSeq.
SIX1 represses senescence and promotes SOX2-mediated cellular plasticity during tumorigenesis.
Specimen part, Subject
View SamplesA total of 332 genes were identified which modified their expression in a dose-dependent manner upon exposure to doxycycline. The more represented cellular pathways included all mitochondrial genes, the endoplasmic reticulum stress response, integrins and extracellular matrix components, and growth factors. Overall design: Examination of 4 different doses of doxycycline in ten human pterygium samples.
Transcriptomic profiling explains racial disparities in pterygium patients treated with doxycycline.
Specimen part, Treatment, Subject
View SamplesGenes were identified which modified their expression in a dose-dependent manner upon exposure to doxycycline. The more represented cellular pathways included all mitochondrial genes, the endoplasmic reticulum stress response, integrins and extracellular matrix components, and growth factors. Overall design: Examination of 4 different doses of doxycycline in three human pterygium samples.
Transcriptomic profiling explains racial disparities in pterygium patients treated with doxycycline.
No sample metadata fields
View SamplesOSM increases the antiviral effect of IFN in Huh7 cells infected with hepatitis A virus (HAV) or HCV replicon and synergizes with IFN in the induction of antiviral genes
Oncostatin M enhances the antiviral effects of type I interferon and activates immunostimulatory functions in liver epithelial cells.
No sample metadata fields
View SamplesEnteroendocrine L-cells release hormones that control metabolism and appetite and are targets under investigation for the treatment of diabetes and obesity. Understanding L-cell diversity and expression profiles is critical for identifying target receptors that will translate into altered hormone secretion. We performed single cell RNA sequencing of mouse L-cells from the upper small intestine to distinguish cellular populations, revealing that L-cells form 3 major clusters: a group with typical characteristics of classical L-cells, including high expression of Gcg and Pyy; a cell type overlapping with Gip-expressing K-cells; and a unique cluster expressing Tph1 and Pzp that was predominantly located in duodenal villi and co-produced 5HT. Expression of G-protein coupled receptors differed between clusters, suggesting the cell types are differentially regulated, and would be differentially targetable. Our findings support the emerging concept that many enteroendocrine cell populations are highly overlapping, with individual cells producing a range of peptides previously assigned to distinct cell types. Overall design: Single cell RNA sequencing of mouse duodenal L-cells cells
Single-cell RNA-sequencing reveals a distinct population of proglucagon-expressing cells specific to the mouse upper small intestine.
Specimen part, Subject
View SamplesMultiple myeloma (MM) cells were treated with the BET inhibitor CPI203 alone and in combination with lenalidomide plus dexamethasone in vitro and in vivo (mouse xenograft).
The BET bromodomain inhibitor CPI203 improves lenalidomide and dexamethasone activity in <i>in vitro</i> and <i>in vivo</i> models of multiple myeloma by blockade of Ikaros and MYC signaling.
Specimen part, Cell line, Treatment
View SamplesHeterochromatin protein 1a (HP1a) is a chromatin associated protein that has been well studied in many model organisms, such as Drosophila, where it is a determining factor for classical heterochromatin. HP1a is associated with the two histone methyltransferases SETDB1 and Su(var)3-9, which mediate H3K9 methylation marks and participate in the establishment and spreading of HP1a enriched chromatin. While HP1a is generally regarded as a factor that represses gene transcription, several reports have linked HP1a binding to active genes, and in some cases, it has been shown to stimulate transcriptional activity. To clarify the function of HP1a in transcription regulation and its association with Su(var)3-9, SETDB1 and the chromosome 4 specific protein POF, we conducted genome-wide expression studies and combined the results with available binding data in Drosophila melanogaster. The results suggested that HP1a has a repressing function on chromosome 4, where it preferentially targets non-ubiquitously expressed genes (NUEGs), and a stimulating function in pericentromeric regions. Further, we showed that the effects of SETDB1 and Su(var)3-9 are similar to HP1a, and on chromosome 4, Su(var)3-9, SETDB1 and HP1a target the same genes. In contrast, transposons are repressed by HP1a and Su(var)3-9 but are un-affected by SETDB1 and POF. In addition, we found that the binding level and expression effects of HP1a are affected by gene length. Our results indicate that genes have adapted to be properly expressed in their local chromatin environment.
HP1a, Su(var)3-9, SETDB1 and POF stimulate or repress gene expression depending on genomic position, gene length and expression pattern in Drosophila melanogaster.
No sample metadata fields
View SamplesStudy of single and double mutants of the two roX RNAs in D. melanogaster Overall design: Study of single and double mutants of the two roX RNAs in D. melanogaster
RNA-on-X 1 and 2 in Drosophila melanogaster fulfill separate functions in dosage compensation.
Specimen part, Cell line, Subject
View SamplesThe aim was to identify genes that were commonly influenced by a siRNA targeting PRKCD in breast cancer cell lines.
Down Regulation of CLDND1 Induces Apoptosis in Breast Cancer Cells.
Cell line, Treatment
View SamplesHuman mesenchymal stem cells or multipotent stromal cells (MSCs) are of interest for clinical therapy, in part because of their capacity for proliferation and differentiation. However, results from clinical trials and in vitro models have been variable, possibly due to MSC heterogeneity and a lack of standardization between MSC in vitro expansion protocols. Here we defined changes in MSCs during expansion in vitro. In low density cultures, MSCs expand through distinct lag, exponential growth and stationary phases. We assayed cultures of passage 2 human MSCs from three donors at low density (50 cells/cm2) at about 5% confluence on Day 2 and after the cultures had expanded to about 70% confluence on Day 7. On Day 2 genes involved in cell division were up-regulated. On Day 7 genes for cell development were up-regulated. The variations between three donors were less than the variation within the expansion of MSCs from a single donor. The microarray data for selected genes were confirmed by real-time PCR, ELISA and FACScan. About 50% of cells at Day 2 were in S-phase compared to 10% at Day 7. The results demonstrated major differences in early and late stage cultures of MSCs that should be considered in using the cells in experiments and clinical applications.
Human multipotent stromal cells undergo sharp transition from division to development in culture.
No sample metadata fields
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