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GSE26801
Saccharomyces cerevisiae
2 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
The ARV1-encoded protein mediates sterol transport from the endoplasmic reticulum (ER) to the plasma membrane. Yeast ARV1 mutants accumulate multiple lipids in the ER and are sensitive to pharmacological modulators of both sterol and sphingolipid metabolism. Using fluorescent and electron microscopy, we demonstrate sterol accumulation, subcellular membrane expansion, elevated lipid droplet formation and vacuolar fragmentation in ARV1 mutants. Motif-based regression analysis of ARV1 deletion transcription profiles indicates activation of Hac1p, an integral component of the UPR. Accordingly, we show constitutive splicing of HAC1 transcripts, induction of a UPR reporter and elevated expression of UPR targets in ARV1 mutants. IRE1, encoding the unfolded protein sensor in the ER lumen, exhibits a lethal genetic interaction with ARV1, indicating a viability requirement for the UPR in cells lacking ARV1. Surprisingly, ARV1 mutants expressing a variant of Ire1p defective in sensing unfolded proteins are viable. Moreover these strains also exhibit constitutive HAC1 splicing that interacts with DTT-mediated perturbation of protein folding. These data suggest a component of UPR induction in arv1? strains is distinct from protein misfolding. Decreased ARV1 expression in murine macrophages also results in UPR induction, particularly up-regulation of activating transcription factor-4, C/EBP homologous protein (CHOP) and apoptosis. Cholesterol loading or inhibition of cholesterol esterification further elevated CHOP expression in ARV1 knockdown cells. Thus, loss or down-regulation of ARV1 disturbs membrane and lipid homeostasis resulting in a disruption of ER integrity, one consequence of which is induction of the UPR.
Publication Title
Loss of subcellular lipid transport due to ARV1 deficiency disrupts organelle homeostasis and activates the unfolded protein response.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Telomere erosion causes cell mortality, suggesting that longer telomeres allow greater number of cell division. In telomerase-positive human cancer cells, however, telomeres are often kept shorter than the surrounding normal tissues. Recently, we have shown that telomere elongation in cancer cells represses innate immune genes and promotes their differentiation in vivo. This implies that short telomeres contribute to cancer malignancy, but it is unclear how such genetic repression is caused by long telomeres. Here we report that telomeric repeat-containing RNA (TERRA) induces genome-wide alteration of gene expression in telomere-elongated cancer cells in vivo. Using three different cell lines, we found that G4 forming oligonucleotide repressed innate immune genes in vivo 3D culture conditions. Most of the suppressed genes belonged to innate immune system categories and were upregulated in various cancers. We propose that TERRA G4 counteracts cancer malignancy through suppression of innate immune genes.
Publication Title
Telomeric repeat-containing RNA/G-quadruplex-forming sequences cause genome-wide alteration of gene expression in human cancer cells in vivo.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Telomere erosion causes cell mortality, suggesting that longer telomeres allow greater number of cell division. In telomerase-positive human cancer cells, however, telomeres are often kept shorter than the surrounding normal tissues. Recently, we have shown that telomere elongation in cancer cells represses innate immune genes and promotes their differentiation in vivo. This implies that short telomeres contribute to cancer malignancy, but it is unclear how such genetic repression is caused by long telomeres. Here we report that telomeric repeat-containing RNA (TERRA) induces genome-wide alteration of gene expression in telomere-elongated cancer cells in vivo. Using three different cell lines, we found that telomere elongation upregulates TERRA and downregulates innate immune genes in vivo xenograft tumors. Most of the suppressed genes belonged to innate immune system categories and were upregulated in various cancers. We propose that TERRA G4 counteracts cancer malignancy through suppression of innate immune genes.
Publication Title
Telomeric repeat-containing RNA/G-quadruplex-forming sequences cause genome-wide alteration of gene expression in human cancer cells in vivo.
Sample Metadata Fields
Disease, Cell line
View Samples- Homo sapiens
- 3 Downloadable Samples
IonTorrentProton
Description
Tumor-specific alternative splicing is implicated in the progression of cancer, including clear cell renal cell carcinoma (ccRCC). Using ccRCC RNA-sequencing data from The Cancer Genome Atlas, we found that epithelial splicing regulatory protein 2 (ESRP2), one of the key regulators of alternative splicing in epithelial cells, is expressed in ccRCC. ESRP2 mRNA expression did not correlate with the overall survival rate of ccRCC patients, but the expression of some ESRP-target exons correlated with the good prognosis and with the expression of Arkadia (also known as RNF111) in ccRCC. Arkadia physically interacted with ESRP2, induced polyubiquitination, and modulated its splicing function. Arkadia and ESRP2 suppressed ccRCC tumor growth in a coordinated manner. Lower expression of Arkadia correlated with advanced tumor stages and poor outcomes in ccRCC patients. This study thus reveals a novel tumor-suppressive role of the Arkadia-ESRP2 axis in ccRCC. Overall design: Expression of mRNA in a ccRCC cell line OS-RC-2 under the knockdown of Arkadia or ESRP2. Knock-down of ESRP2 was confirmed by RT-PCR because of low expression of ESRP2 which resulted in non-quantitative FPKM value.
Publication Title
The Arkadia-ESRP2 axis suppresses tumor progression: analyses in clear-cell renal cell carcinoma.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
- IonTorrentProton
Description
We evaluated the role of Arkadia and ESRP2 in HEK293T cells Overall design: Expression of mRNA in HEK293T cells under the knockdown of Arkadia or ESRP2
Publication Title
The Arkadia-ESRP2 axis suppresses tumor progression: analyses in clear-cell renal cell carcinoma.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 30 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Regeneration of fragmented Drosophila imaginal discs occurs in an epimorphic manner, involving local cell proliferation at the wound site. Following disc fragmentation, cells at the wound site activate a restoration program through wound healing, regenerative cell proliferation and repatterning of the tissue. However, the interplay of signaling cascades, driving these early reprogramming steps, is not well understood. Here we profiled the transcriptome of regenerating cells in the early phase within twenty-four hours after wounding. We found that JAK/STAT signaling becomes activated at the wound site and promotes regenerative cell proliferation in cooperation with Wingless (Wg) signaling. In addition, we demonstrated that the expression of Drosophila insulin-like peptide 8 (dilp8), which encodes a paracrine peptide to delay the onset of pupariation, is controlled by JAK/STAT signaling in early regenerating discs. Our findings suggest that JAK/STAT signaling plays a pivotal role in coordinating regenerative disc growth with organismal developmental timing.
Publication Title
During Drosophila disc regeneration, JAK/STAT coordinates cell proliferation with Dilp8-mediated developmental delay.
Sample Metadata Fields
Sex, Specimen part, Treatment
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Glioblastoma (GBM) is a lethal brain cancer composed of heterogeneous cellular populations including glioma stem cells (GSCs) and their progeny differentiated non-stem glioma cells (NSGCs). Although accumulating evidence points out the significance of GSCs for tumour initiation and propagation, the roles of NSGCs remain elusive. Here we demonstrate that, when patient-derived GSCs in GBM tumours undergo differentiation with diminished telomerase activity and shortened telomeres, they subsequently become senescent phenotype, thereby secreting angiogenesis-related proteins, including vascular endothelial growth factors. Interestingly, these secreted factors from senescent NSGCs promote proliferation of human umbilical vein endothelial cells and tumorigenic potentials of GSCs in immunocompromised mice. These experimental data are likely clinically-relevant, since immunohistochemistry of both patient tumours of GBM and the patient GSC-derived mouse xenografted tumours detected tumour cells that express a set of markers for the senescence phenotype. Collectively, our data suggest that the inter-cellular signals from senescent NSGCs promote GBM tumour angiogenesis thereby increasing malignant progression of GBM.
Publication Title
Senescence from glioma stem cell differentiation promotes tumor growth.
Sample Metadata Fields
Specimen part, Time
View Samples- Homo sapiens
- 15 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Limitless reproductive potential is one of the hallmarks of cancer cells1. This ability is accomplished by maintaining telomeres, which erosion otherwise causes cellular senescence or death. Human cancer cells often maintain shorter telomeres than do cells in surrounding normal tissues2-5. While most cancer cells activate telomerase, which can elongate telomeres6, it remains elusive why cancer cells keep telomeres short. Here we show that forced elongation of telomeres in cancer cells promotes their differentiation in a tumor microenvironment in vivo. We elongated telomeres of human prostate cancer PC-3 cells, which possess short telomeres7, by enhancing their telomerase activity. The resulting cells with long telomeres retain an ability to form tumors in a mouse xenograft model. Strikingly, these tumors exhibit many duct-like structures and reduced N-cadherin expression, reminiscent of well-differentiated adenocarcinoma. These phenotypic changes are caused by telomere elongation per se but not enhanced telomerase activity. Gene expression profiling revealed that telomere elongation correlates with inhibition of cell-cycle processes. Together, our results suggest a functional contribution of short telomeres to tumor malignancy by regulating cancer cell differentiation.
Publication Title
Telomere length influences cancer cell differentiation in vivo.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Limitless reproductive potential is one of the hallmarks of cancer cells1. This ability is accomplished by maintaining telomeres, which erosion otherwise causes cellular senescence or death. Human cancer cells often maintain shorter telomeres than do cells in surrounding normal tissues2-5. While most cancer cells activate telomerase, which can elongate telomeres6, it remains elusive why cancer cells keep telomeres short. Here we show that forced elongation of telomeres in cancer cells promotes their differentiation in a tumor microenvironment in vivo. We elongated telomeres of human prostate cancer PC-3 cells, which possess short telomeres7, by enhancing their telomerase activity. The resulting cells with long telomeres retain an ability to form tumors in a mouse xenograft model. Strikingly, these tumors exhibit many duct-like structures and reduced N-cadherin expression, reminiscent of well-differentiated adenocarcinoma. These phenotypic changes are caused by telomere elongation per se but not enhanced telomerase activity. Gene expression profiling revealed that telomere elongation correlates with inhibition of cell-cycle processes. Together, our results suggest a functional contribution of short telomeres to tumor malignancy by regulating cancer cell differentiation.
Publication Title
Telomere length influences cancer cell differentiation in vivo.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Previously published data suggested some redundant functions between HDAC1 and HDAC2 in mouse. To test this hypothesis, we used microarrays to have a genome wide analysis at the transcription level of primary MEFs lacking HDAC1, HDAC2.
Publication Title
Histone deacetylases 1 and 2 act in concert to promote the G1-to-S progression.
Sample Metadata Fields
Sex
View Samples