Oncogenic mutations in BRAF and NRAS occur in 70% of melanomas. Here we identify a microRNA, miR-146a, that is highly upregulated by oncogenic BRAF and NRAS. Expression of miR-146a increases the ability of human melanoma cells to proliferate in culture and form tumors in mice, whereas knockdown of miR-146a has the opposite effects. We show these oncogenic activities are due to miR-146a targeting the NUMB mRNA, a repressor of Notch signaling. Previous studies have shown that pre-miR-146a contains a single nucleotide polymorphism (C>G rs2910164). We find that the ability of pre-miR-146a/G to activate Notch signaling and promote oncogenesis is substantially higher than that of pre-miR-146a/C. Analysis of melanoma cell lines and matched patient samples indicates that during melanoma progression pre-miR-146a/G is enriched relative to pre-miR-146a/C, resulting from a C-to-G somatic mutation in pre-miR-146a/C. Collectively, our results reveal a central role for miR-146a in the initiation and progression of melanoma.
miR-146a promotes the initiation and progression of melanoma by activating Notch signaling.
Cell line
View SamplesOncogenic mutations in BRAF and NRAS occur in 70% of melanomas. Here we identify a microRNA, miR-146a, that is highly upregulated by oncogenic BRAF and NRAS. Expression of miR-146a increases the ability of human melanoma cells to proliferate in culture and form tumors in mice, whereas knockdown of miR-146a has the opposite effects. We show these oncogenic activities are due to miR-146a targeting the NUMB mRNA, a repressor of Notch signaling. Previous studies have shown that pre-miR-146a contains a single nucleotide polymorphism (C>G rs2910164). We find that the ability of pre-miR-146a/G to activate Notch signaling and promote oncogenesis is substantially higher than that of pre-miR-146a/C. Analysis of melanoma cell lines and matched patient samples indicates that during melanoma progression pre-miR-146a/G is enriched relative to pre-miR-146a/C, resulting from a C-to-G somatic mutation in pre-miR-146a/C. Collectively, our results reveal a central role for miR-146a in the initiation and progression of melanoma. Overall design: WI-38 cells were either infected with BRAFV600E or Empty retroviral vectors and small RNA were prepared from these cells. As an additional control, WI-38 cells were serum starved and used to generate quiscent cells, which were also used to prepase small RNA. The small RNA were then used to generate small RNA library and were used on Illumina genome analyzer.
miR-146a promotes the initiation and progression of melanoma by activating Notch signaling.
Specimen part, Cell line, Subject
View SamplesWe measured gene expression in the adrenal glands of the Spontaneously Hypertensive Rat (SHR) and Wistar-Kyoto rat (WKY) using Affymetrix RG-U34A GeneChips. All rats were aged-matched at 4-weeks. The rats were obtained from the colonies at the Univeristy of California San Diego, La Jolla, CA.
Common genetic mechanisms of blood pressure elevation in two independent rodent models of human essential hypertension.
No sample metadata fields
View SamplesWe performed Affymetrix MG-U74Av2 GeneChip experiements on mRNA from the adrenal glands of the BPH hypertensive and BPL hypotensive mouse strains. All mice were aged-matched at 5 weeks. We obtained the mice from Jackson Laboratories, Bar Harbor, ME.
Neuroendocrine transcriptome in genetic hypertension: multiple changes in diverse adrenal physiological systems.
No sample metadata fields
View SamplesThe targeting of oncogenic ‘driver’ kinases with small molecule inhibitors has proven to be a highly effective therapeutic strategy in selected non-small cell lung cancer (NSCLC) patients. However, acquired resistance to targeted therapies invariably arises and is a major limitation to patient care. ROS1 fusion proteins are a recently described class of oncogenic driver, and NSCLC patients that express these fusions generally respond well to ROS1-targeted therapy. In this study, we sought to determine mechanisms of acquired resistance to ROS1 inhibition. To accomplish this, we generated a ROS1 inhibition-resistant derivative of the initially sensitive NSCLC cell line HCC78.
Resistance to ROS1 inhibition mediated by EGFR pathway activation in non-small cell lung cancer.
No sample metadata fields
View SamplesOver expression of recombinant proteins is known to cause a metabolic burden to the host cells which leads to down regulation of both growth rates and protein expression. Most studies in this regard have been conducted in low density shake flask cultures which does not capture the essential features of an industrial scale bioprocess. In the present work we studied the transcriptomic profiling at different specific growth rates while expressing the recombinant human interferon beta in fed batch cultures with complex media. These conditions mimicked the industrial fermentations for recombinant proteins.
Comparative transcriptomic profile analysis of fed-batch cultures expressing different recombinant proteins in Escherichia coli.
No sample metadata fields
View SamplesThe objective of this work was to design an improved host platform for recombinant protein expression in E. coli. The approach involves first to create a library of the E. coli genomic DNA in different expression vectors and screen for probable transcripts which may lead to slow growing colonies and also simultaneously over-expression of recombinant proteins. To observe its effect on host performance, these genes were knocked out from the E. coli genome. A CG2 strain has been created by knocking in vhb gene gene downstream of the acetate promoter and knocking down ribB gene in DH5 and transformed with Recombinant GFP cloned in pBAD33.
Comparative transcriptomic profile analysis of fed-batch cultures expressing different recombinant proteins in Escherichia coli.
No sample metadata fields
View SamplesStrong production of recombinant proteins interfere with cellular processes in many ways. The extent of the bacterial stress response is determined by the specific properties of the recombinant protein, and by the rates of transcription and translation. The consideration of bacterial stress and starvation responses is of crucial importance for the successful establishment of an industrial large scale bioprocess. Stress genes can be used as marker genes in order to monitor the fitness of industrial bacterial hosts during fermentation processes. For this purpose, here in our study we have applied transcriptome analysis for the description of general and specific stress and starvation responses of Escherichia coli. Producing recombinant protein (Xylanase) in high cell density fed batch culture.
Comparative transcriptomic profile analysis of fed-batch cultures expressing different recombinant proteins in Escherichia coli.
Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Global metabolic consequences of the chromogranin A-null model of hypertension: transcriptomic detection, pathway identification, and experimental verification.
Sex, Specimen part
View SamplesThe objective of the experiment is to determine the genes differentially expressed in the liver of the chromogranin A knockout mouse (Mahapatra et al., 2005).
Global metabolic consequences of the chromogranin A-null model of hypertension: transcriptomic detection, pathway identification, and experimental verification.
Sex, Specimen part
View Samples