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GSE65892
Homo sapiens
6 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Hepatocellular carcinoma (HCC) remains a significant clinical challenge with few therapeutic options available to cancer patients. MicroRNA 21-5p (miR-21) has been shown to be upregulated in HCC, but the contribution of this oncomiR to the maintenance of tumorigenic phenotype in liver cancer remains poorly understood. We have developed potent and specific single-stranded oligonucleotide inhibitors of miR-21 (anti-miRs) and used them to interrogate dependency on miR-21 in a panel of liver cancer cell lines. Treatment with anti-miR-21, but not with a mismatch control anti-miR, resulted in significant de-repression of direct targets of miR-21 and led to loss of viability in the majority of HCC cell lines tested. Robust induction of caspase activity, apoptosis and necrosis was noted in anti-miR-21 treated HCC cells. Furthermore, ablation of miR-21 activity resulted in inhibition of HCC cell migration and suppression of clonogenic growth. To better understand the consequences of miR-21
Publication Title
Anti-miR-21 Suppresses Hepatocellular Carcinoma Growth via Broad Transcriptional Network Deregulation.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 30 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Post-chemotherapy relapse presents a major unmet medical need in AML where treatment options are limited. We used gene expression profile from 32 AML cell lines to characterize expression difference between responder and non-responders to PIM inhibitors. Our results highlight the importance of STAT5 and MYC in rendering cancer cells sensitive to PIM inhibitors.
Publication Title
No associated publication
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 28 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The activation of the transcription factor NF-E2-related factor 2 (Nrf2) maintains cellular homeostasis in response to oxidative stress by the regulation of multiple cytoprotective genes. Without stressors the activity of Nrf2 is inhibited by its interaction with the kelch-like ECH-associated protein 1 (Keap1). Here, we describe RA839, a small molecule that binds non-covalently to the Nrf2-interacting kelch domain of Keap1 with a Kd of approximately 6 M, as demonstrated by X-ray co-crystallization and isothermal titration calorimetry. Whole-genome DNA arrays showed that at 10 M RA839 significantly regulated 105 genes in bone marrow-derived macrophages. Canonical pathway mapping of these genes revealed an activation of pathways linked with Nrf2 signalling. These pathways were also activated after the activation of Nrf2 by the silencing of Keap1 expression. RA839 regulated only two genes in Nrf2 knockout macrophages. Similar to the activation of Nrf2 by either silencing of Keap1 expression or by the reactive compound CDDO-Me, RA839 prevented the induction of both inducible nitric oxide synthase expression and nitric oxide release in response to lipopolysaccharides in macrophages. In mice RA839 acutely induced Nrf2-target gene expression in liver. RA839 is a selective inhibitor of the Keap1/Nrf2 interaction and a useful tool compound to study the biology of Nrf2.
Publication Title
Characterization of RA839, a Noncovalent Small Molecule Binder to Keap1 and Selective Activator of Nrf2 Signaling.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The transcription factor NF-E2-related factor 2 (Nrf2) induces cytoprotective genes, but has also been linked to the regulation of hepatic energy metabolism. In order to assess the pharmacological potential of hepatic Nrf2 activation in metabolic disease, Nrf2 was activated over 8 weeks in mice on Western diet using two different siRNAs against kelch-like ECH-associated protein 1 (Keap1), the inhibitory protein of Nrf2. Whole genome expression analysis followed by pathway analysis demonstrated that the suppression of Keap1 expression induced genes that are involved in anti-oxidative stress defense and biotransformation, pathways proving the activation of Nrf2 by the siRNAs against Keap1. The expression of neither fatty acid- nor carbohydrate-handling proteins was regulated by the suppression of Keap1. Metabolic profiling of the animals did also not show effects on plasma and hepatic lipids, energy expenditure or glucose tolerance by the activation of Nrf2. The data indicate that hepatic Nrf2 is not a major regulator of intermediary metabolism in mice.
Publication Title
Chronic Activation of Hepatic Nrf2 Has No Major Effect on Fatty Acid and Glucose Metabolism in Adult Mice.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 16 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Histone deacetylases (HDACs) are important regulators of epigenetic gene modification that are involved in the transcriptional control of metabolism. In particular class IIa HDACs have been shown to affect hepatic gluconeogenesis and previous approaches revealed that their inhibition reduces blood glucose in type 2 diabetic mice. In the present study, we aimed to evaluate the potential of class IIa HDAC inhibition as a therapeutic opportunity for the treatment of metabolic diseases. For that, siRNAs selectively targeting HDAC4, 5 and 7 were selected and used to achieve a combinatorial knockdown of these three class IIa HDAC isoforms. Subsequently, the hepatocellular effects as well as the impact on glucose and lipid metabolism were analyzed in vitro and in vivo. The triple knockdown resulted in a statistically significant decrease of gluconeogenic gene expression in a murine hepatic cell line as well as in human primary hepatocytes. Despite a similar HDAC-induced downregulation of hepatic genes involved in gluconeogenesis in mice using a liver-specific lipid nanoparticle siRNA formulation, the in vivo effects on whole body glucose metabolism were only limited and did not outweigh the safety concerns observed by histopathological analysis in spleen and kidney. Mechanistically, Affymetrix gene chip analysis and gene expression studies provide evidence that class IIa HDACs directly target and thus regulate the expression of HNF4α and FOXP1 in the liver, thereby modifying gene regulatory mechanisms mediating glucose and lipid metabolism and transport. In conclusion, the combinatorial knockdown of HDAC4, 5 and 7 by therapeutic siRNAs affected multiple pathways in vitro and in vivo leading to the downregulation of genes involved in gluconeogenesis. However, the effects on the gene expression level were not paralleled by a significant reduction of gluconeogenesis in mice, as shown in pyruvate tolerance tests. However, the liver-specific inhibition of these HDAC isoforms was associated with severe adverse effects in vivo, making this approach not a viable treatment option for chronic metabolic disorders like type 2 diabetes.
Publication Title
No associated publication
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 30 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
The multi-lab International Life Sciences Institute (ILSI) project on the application of genomics to risk assessment offered the unique opportunity to investigate the influence of variability within and between laboratories on identifying biologically relevant gene expression changes. We assessed the gene expression profiles of mouse lymphoma L5178Y cells treated with hydroxyurea (HU) in three independent studies from two different laboratories, Sanofi-Aventis and Procter and Gamble. Cells were dosed for 4 hr and harvested immediately at the end of the treatment or after a 20-hr recovery period. Cytotoxicity and genotoxicity were evaluated by standard assays. Statistical analysis of these data revealed that, while gene expression responses to HU treatment were markedly different at 4 hr vs. 24 hr, there was otherwise a consistent pattern of dose-response across the three studies. Therefore, the studies were merged and each time point was evaluated separately. At 4 hr, we identified 173 (P lt 0.0001) dose-responsive genes with a common trend in all three studies. These were mainly associated with the cell cycle, DNA repair and DNA metabolism, and in particular, the intra-S and G2/M phase checkpoints. At 24 hr, we identified 434 dose-responsive genes common across studies. These genes were involved in lymphocyte-specific activities and the activation of apoptosis via the caspase cascade. Our results show that despite inter-laboratory variability, combining the three studies in a single statistical analysis identifies more significantly-modulated genes than in any of the individual studies, due to improved statistical sensitivity. The genes identified in our study provide information that is relevant to HU biology.
Publication Title
Laboratory variability does not preclude identification of biological functions impacted by hydroxyurea.
Sample Metadata Fields
Sex, Disease, Disease stage, Compound, Time
View Samples