Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Cells silenced for SDHB expression and tumor phenotype

ABSTRACT: Effect of SDHB silencing using siRNA methodologies in the tumor phenotype; We used microarrays to detail the global programme of gene expression when SDHB is silenced. Experiment Overall Design: Human hepatocellular carcinoma cell line Hep3B was stably silenced with control or SDHB-specific siRNAs.

This experiment was re-loaded into ArrayExpress in November 2010 after manual curation.

ORGANISM(S): Homo sapiens

SUBMITTER: Manolo Mata

PROVIDER: E-GEOD-10289 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Cells silenced for SDHB expression display characteristic features of the tumor phenotype.

Cervera Ana M AM Apostolova Nadezda N Crespo Francisco Luna FL Mata Manuel M McCreath Kenneth J KJ

Cancer research 20080601 11

Recently, enzymes of the tricarboxylic acid (TCA) cycle have emerged as novel tumor suppressors. In particular, mutations in the nuclear-encoded subunits of succinate dehydrogenase (SDHB, SDHC, and SDHD) cause paragangliomas and pheochromocytomas. Although the mechanism(s) by which disruption of mitochondrial metabolism leads to neoplasia is largely unknown, increasing evidence points to an activation of pseudohypoxia. In this study, we have shown that silencing of SDHB using DNA-based small int ...[more]

PMID: 18519664

Similar Datasets

Project description:Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced hepatocellular carcinoma (HCC). However, its benefits is modest, also because its mechanism of action remains elusive, therefore, a better understanding of its molecular action and molecular targets are needed. On the basis of our previous studies, here, we investigated the role of the nuclear protein 1 (NUPR1) in HCC and its role in the context of sorafenib treatment. NUPR1 is a stress-inducible protein over-expressed in different malignancies, however, its role in HCC is not yet fully understood. We found that NUPR1, is over-expressed in 53% of primary human HCC samples. Knockdown of NUPR1 significantly increased cell sensitivity to sorafenib and inhibits cell growth, migration and invasion of HCC cells in vitro and tumorigenicity in vivo. Moreover, NUPR1 silencing influenced expression of target genes RelB and IER3. Unsurprisingly, RelB and IER3 knockdown also inhibited HCC cells viability, growth and migration. By gene expression profiling of HCC cells following stable NUPR1 knockdown, we found that genes functionally involved in cell death and survival, cellular response to therapies, lipid metabolism, cell growth and proliferation, molecular transport and cellular movement were mostly suppressed. Network analysis of dynamic gene expression identified NF-ÎºB and ERK as down-regulated gene nodes, and several genes known to be involved in hepatocarcinogenesis were also suppressed. In addition, we identified Runt-related transcription factor 2 (RUNX2) gene as a NUPR1 down-regulated gene. We also demonstrated that RUNX2 gene silencing inhibited HCC cells viability, growth, migration and increased cell sensitivity to sorafenib. Conclusion: We propose that NUPR1/RELB/IER3/RUNX2 pathway play pivotal role in hepatocarcinogenesis. The identification of NUPR1/RELB/IER3/RUNX2 pathway as a potential therapeutic target may contribute to the development of new treatment strategies for HCC management. To better understand the molecular mechanisms of NUPR1 gene action in ovarian HCC cells, we employed the Agilent Whole Human Genome microarrays, containing ~ 44,000 genes to identify global gene expression changes upon NUPR1 suppression in HCC cells. We compared the gene expression of the previously selected shRNA-mediated NURP1-knockdown Hep3B clone against the corresponding control (ctrl) clone. The microarray experiments were performed in duplicates, as two hybridizations were carried out for the NUPR1-suppressing cell clone against the corresponding control, using a fluorescent dye reversal (dye-swap) technique.

Project description:Purpose: We identified KPC1 as the ubiquitin ligase that binds to the p105 precursor of NF-kB, ubiquitinates it and mediates its proteasomal processing to generate the p50 active subunit of the transcription factor. Using U87-MG human glioblastoma xenografts, we observed that overexpression of KPC1 results in strong inhibition of tumor growth mediated via excessive generation of p50.The goal of this RNASeq study was to analyze the profile of gene expression in xenografts overexpressing control (V0), KPC1 or p50 vectors, and to further understand how the altered gene expression patterns can explain the tumor suppressive effect we observed. Results:Transcript analysis of U87-MG xenografts overexpressing control (V0), KPC1 or p50 vector mapped to the human genome revealed: • A strong similarity between overexpression of p50 and KPC1 (correlation of 0.51, p-value<10-300 ) • A specific signature of NF-kB targets [21 of the consistently changed genes are known to be regulated by NF-kB (p-value<3.4×10-9 )] • A significant (p-value<1.4×10-18) increase in the expression of 40 tumor suppressor genes, with no significant change in other classes. • A significant down regulation of a cluster of genes including LIN28B, IL-6, HMAGA2 and VEGFA. This finding links well to an established regulatory axis involving LIN28B, Let-7 microRNA, and IL-6 in inflammation and cell transformation that is regulated by NF-kB. Exponentially growing U87-MG cells were stably transfected with an empty vector (V0) or vectors coding for Myc-KPC1 or Flag-p50. Cells were dissociated with trypsin, washed with PBS, and brought to a concentration of 50×10^6 cells/ml. Cell suspension (5×10^6/0.1 ml) was inoculated subcutaneously at the right flank of 7-weeks old male Balb/C nude mice (n=7). Following 21 days, mRNA from U87-MG xenografts was isolated using an RNA purification kit, and analyzed using the Illumina HiSeq 2500 sequencer. The RNASeq analysis experiment was repeated twice independently. Run1 included a total of 7 samples. Samples 1-3 were isolated from V0 – control tumors (3 different tumors), samples 4-5 were isolated from KPC1-expressing tumors (2 different pools of 3 tumors each due to small tumor size), and samples 6-7 were isolated from p50-expressing tumors for (2 different pools of 2-3 tumors each, due to very small tumor size). Run2 included a total of 5 samples. Samples 8-10 were isolated from V0 (control) tumors (3 different tumors), samples 11-12 were isolated from KPC1 tumors (2 different pools of 3 tumors each due to small tumor size). Several repeated attempts to extract RNA from the p50-expressing tumors did not yield any results, as the tumors were miniscule.

Dataset Information

Cells silenced for SDHB expression and tumor phenotype

Publications

Cells silenced for SDHB expression display characteristic features of the tumor phenotype.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets