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GSE6495
Homo sapiens
6 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In T-cell acute lymphoblastic leukemia (T-ALL) NOTCH 1 receptors are frequently mutated. This leads to aberrantly high Notch signaling, but how this translates into deregulated cell cycle control and the transformed cell type is poorly understood. In this report, we analyze downstream responses resulting from the high level of NOTCH 1 signaling in T-ALL. Notch activity, measured immediately downstream of the NOTCH 1 receptor, is high, but expression of the canonical downstream Notch response genes HES 1 and HEY 2 is low both in primary cells from T-ALL patients and in T-ALL cell lines. This suggests that other immediate Notch downstream genes are activated, and we found that Notch signaling controls the levels of expression of the E3 ubiquitin ligase SKP2 and its target protein p27Kip1. We show that in T-ALL cell lines, recruitment of NOTCH 1 ICD to the SKP2 promoter was accompanied by high SKP2 and low p27Kip1 protein levels were low. In contrast, pharmacologically blocking Notch signaling reversed this picture and led to loss of NOTCH 1 ICD occupancy of the SKP2 promoter, decreased SKP2 and increased p27Kip1 expression. T-ALL cells show a rapid G1-S cell cycle transition, while blocked Notch signaling resulted in G0/G1 cell cycle arrest, also observed by transfection of p27Kip1 or, to a smaller extent, a dominant negative SKP2 allele. Collectively, our data suggest that the aberrantly high Notch signaling in T-ALL maintains SKP2 at a high level and reduces p27Kip1, which leads to more rapid cell cycle progression.
Publication Title
Notch signaling induces SKP2 expression and promotes reduction of p27Kip1 in T-cell acute lymphoblastic leukemia cell lines.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Since its discovery as a tumour suppressor some fifteen years ago, the transcription factor p53 has attracted paramount attention for its role as the guardian of the genome. TP53 mutations occur so frequently in cancer, regardless of patient age or tumour type, that they appear to be part of the life history of at least 50% of human tumours. In most tumours that retain wild-type p53, its function is inactivated due to deregulated HDM2, a protein which binds to p53 and which can inhibit the transcriptional activity of p53 and induce its degradation.
Publication Title
Ablation of key oncogenic pathways by RITA-reactivated p53 is required for efficient apoptosis.
Sample Metadata Fields
Specimen part, Disease
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Targeting oncogene addiction is a promising strategy for anti-cancer therapy. Here, we report a potent inhibition of crucial oncogenes by p53 upon reactivation with small molecule RITA in vitro and in vivo. RITA-activated p53 unleashes transcriptional repression of anti-apoptotic proteins Mcl-1, Bcl-2, MAP4, and survivin, blocks Akt pathway on several levels and downregulates c-Myc, cyclin E and B-catenin. p53 ablates c-Myc expression via several mechanisms at transcriptional and posttranscriptional level. We show that transrepression of oncogenes correlated with higher level of p53 bound to chromatin-bound p53 than transactivation of pro-apoptotic targets. Inhibition of oncogenes by p53 reduces the cells ability to buffer pro-apoptotic signals and elicits robust apoptosis. Our study highlights the role of transcriptional repression for p53-mediated tumor suppression.
Publication Title
Ablation of key oncogenic pathways by RITA-reactivated p53 is required for efficient apoptosis.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
FVB mice were engineered to express wild-type human cyclin E under control of the human surfactant C promoter (CEO mice; Ma et al, PNAS 2007). These mice develop spontaneous lung tumors, which were shown to be adenocarcinoma by histological analysis. Here we compare whole-genome RNA expression levels between the tumors and normal lung of 4 CEO mice as well as 4 nontransgenic animals.
Publication Title
Evidence for tankyrases as antineoplastic targets in lung cancer.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 19 Downloadable Samples
Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Mitochondrial dysfunction has been directly or indirectly implicated in the pathogenesis of a number of neurodegenerative disorders including Parkinson's disease, Alzheimer's disease and Amyotrophic Lateral Sclerosis (ALS). We used exon-sentive microarrays to characterize the responses to different mitochondrial perturbations in cellular models. We examined human SH-SY5Y neuroblastoma cells treated with paraquat, a neurotoxic herbicide which both catalyzes the formation of reactive oxygen species (ROS) and induces mitochondrial damage in animal models, and SH-SY5Y cells stably expressing the mutant SOD1(G93A) protein, one of the genetic causes of ALS. We identified a common set of genes that have a deregulated transcription and alternative splicing in both models. Noticeably, pathway analysis revealed that the expression of a subset of genes involved in neuritogenesis and axon guidance is perturbed, suggesting that alterations of axonal function may descend directly from mitochondrial damage and be responsible for neurodegenerative conditions.
Publication Title
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Whole-genome profiling of SH-SY5Y cells was done on neuroblastoma SH-SY5Y stably transfected with cDNAs coding for SOD1WT or the mutant SOD1(G93A) protein.
Publication Title
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Human SH-SY5Y neuroblastoma cells treated with paraquat, a neurotoxic herbicide which both catalyzes the formation of reactive oxygen species (ROS) and induces mitochondrial damage in animal models was profiled using Affimetrix Exon 1.0 ST GeneChips
Publication Title
Mutant SOD1 and mitochondrial damage alter expression and splicing of genes controlling neuritogenesis in models of neurodegeneration.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
E-cadherin, a protein encoded by the CDH1 gene is the dominant epithelial cell adhesion molecule playing a crucial role in epithelial tissue polarity and structural integrity. The progression of 90% or more carcinomas is believed to be mediated by disruption of normal E-cadherin expression, subcellular localization or function. Despite the strong correlation between E-cadherin loss and malignancy the mechanism through how this occurs is not known in most sporadic and hereditary epithelial carcinomas. Previous works have shown the importance of CDH1 intron 2 sequences for proper gene and protein expression supporting the possibility of these being cis-modulators of E-cadherin expression/function. but when co-expressed it led to reduced cell-cell adhesiveness, increased invasion and angiogenesis. By expression array analysis, IFITM1 and IFI27 levels were found to be increased upon CDH1a overexpression. Importantly, CDH1a was found to be de novo expressed in gastric cancer cell lines when compared to normal stomach.
Publication Title
Transcription initiation arising from E-cadherin/CDH1 intron2: a novel protein isoform that increases gastric cancer cell invasion and angiogenesis.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Genome 430A 2.0 Array (mouse430a2)
Description
Hepatocellular carcinoma (HCC) represents a major health problem as it afflicts an increasing number of patients worldwide. Albeit most of the risk factors for HCC are known, this is a deadly syndrome with a life expectancy at the time of diagnosis of less than 1 year. Definition of the molecular principles governing the neoplastic transformation of the liver is an urgent need to facilitate the clinical management of patients, based on innovative methods to detect the disease in its early stages and on more efficient therapies. In the present study we have combined the analysis of a murine model and human samples of HCC to identify genes differentially expressed early in the process of hepatocarcinogenesis, using a microarray based approach. Expression of 190 genes was impaired in murine HCC from which 65 were further validated by low-density array RT PCR. The expression of the best 45 genes was then investigated in human samples resulting in 18 genes which expression was significantly modified in HCC. Among them, JUN, methionine adenosyltransferase 1A and 2A, phosphoglucomutase 1, and acyl CoA dehydrogenase short branched chain indicate defective cell proliferation as well as one carbon pathway, glucose and fatty acid metabolism, both in HCC and cirrhotic liver, a well known preneoplastic condition. These alterations were further confirmed in public transcriptomic datasets from other authors. In addition, vasodilator stimulated phosphoprotein, an actin-associated protein involved in cytoskeleton remodelling, was also found to be increased in the liver and serum of cirrhotic and HCC patients. In addition to revealing the impairment of central metabolic pathways for liver homeostasis, further studies may probe the potential value of the reported genes for the early detection of HCC.
Publication Title
A signature of six genes highlights defects on cell growth and specific metabolic pathways in murine and human hepatocellular carcinoma.
Sample Metadata Fields
Specimen part
View Samples- Macaca mulatta
- 14 Downloadable Samples
- Affymetrix Rhesus Macaque Genome Array (rhesus)
Description
Derivation of embryonic stem cells (ESC) genetically identical to a patient by somatic cell nuclear transfer (SCNT) holds the potential to cure or alleviate the symptoms of many degenerative diseases while circumventing any immunorejection issues. However, no primate nuclear transfer embryonic stem (ntES) cell lines have been derived to date. Here, we used a modified SCNT technique to produce rhesus macaque SCNT blastocysts at a relatively high efficiency from adult donor cells and we successfully derived two primate ntES cell lines from 304 oocytes (an overall efficiency of 0.7%). Nuclear and mitochondrial DNA analysis confirmed the ntES cell lines were derived from rhesus monkey SCNT blastocysts and both rhesus monkey ntES cell lines exhibited a normal ESC morphology, expressed key stemness markers, were transcriptionally indistinguishable from control ESC lines and differentiated into multiple cell types. This is, to our knowledge, the first confirmed derivation of primate ntES cell lines.
Publication Title
Producing primate embryonic stem cells by somatic cell nuclear transfer.
Sample Metadata Fields
No sample metadata fields
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