Lipid mobilization (lipolysis) in white adipose tissue (WAT) critically controls lipid turnover and adiposity in humans. While the acute regulation of lipolysis has been studied in detail, the transcriptional determinants of WAT lipolytic activity remain still largely unexplored. Here we show that the genetic inactivation of transcriptional co-factor transducin beta-like-related (TBLR) 1 blunts the lipolytic response of white adipocytes through the impairment of cAMP-dependent signal transduction. Indeed, mice lacking TBLR1 in adipocytes are defective in fasting-induced lipid mobilization and when placed on a high fat diet show aggravated adiposity, glucose intolerance and insulin resistance. TBLR1 levels are found to increase under lipolytic conditions in WAT of both human patients and mice, correlating with serum free fatty acids (FFA). As a critical regulator of WAT cAMP signaling and lipid mobilization, proper activity of TBLR1 in adipocytes may thus represent a critical molecular checkpoint for the prevention of metabolic dysfunction in subjects with obesity-related disorders.
Transcriptional cofactor TBLR1 controls lipid mobilization in white adipose tissue.
Specimen part, Treatment
View SamplesPancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer fatalities in Western societies, characterized by high metastatic potential and resistance to chemotherapy. Critical molecular mechanisms of these phenotypical features still remain unknown, thus hampering the development of effective prognostic and therapeutic measures in PDAC. Here we show that transcriptional co-factor Transducin beta-like (TBL) 1 was over-expressed in both human and murine PDAC. Inactivation of TBL1 in human and mouse pancreatic cancer cells reduced cellular proliferation and enhanced chemosensitivity, correlating with diminished glucose uptake, glycolytic flux, and PI3kinase signaling. TBL1 deficiency both prevented and reversed pancreatic tumor growth in mice, triggering transcriptional PI3kinase inhibition also in vivo. As TBL1 mRNA levels were also found to correlate with overall and disease-free survival in a cohort of human PDAC patients and to predict therapy responsiveness in these subjects, TBL1 expression may serve both as a novel prognostic marker and molecular target in the treatment of human PDAC.
Transcriptional co-factor Transducin beta-like (TBL) 1 acts as a checkpoint in pancreatic cancer malignancy.
Cell line, Treatment
View SamplesPurpose: The goal of the study was to integrate verified signals from previous genetic association studies with gene expression and pathway analysis for discovery of new candidate genes and signalling networks, relevant for rheumatoid arthritis (RA). Method:RNA-seq based expression analysis of 377 genes from previously verified RA-associated loci was performed in blood cells from 5 newly diagnosed, non-treated RA patients, 7 patients with treated RA and 12 healthy controls. Differentially expressed genes sharing a similar expression pattern in treated and untreated RA sub-groups were selected for pathway analysis. A set of “connector” genes derived from pathway analysis was then tested for differential expression in the initial discovery cohort. Results: 11 qualifying genes were selected for pathway analysis and grouped into 2 evidence-based functional networks, containing 29 and 27 additional “connector” molecules. The expression of genes, corresponding to connector molecules was then tested in the initial RNA-seq data. 3 genes showed similar expression difference in both treated and non-treated RA patients and additional nine genes were differentially expressed in at least one patients' group compared to healthy controls. Conclusion: Integration of RNA-seq data with findings from association studies, and consequent pathway analysis implicate new candidate genes in the pathogenesis of RA. Overall design: Illumina RNA-seq was performed on RNA from pereferial blood mononuclear cells taken from 12 healthy individuals, 5 untreated RA patients, and 7 treated RA patients
Discovery of new candidate genes for rheumatoid arthritis through integration of genetic association data with expression pathway analysis.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Leukemic transformation by the MLL-AF6 fusion oncogene requires the H3K79 methyltransferase Dot1l.
Specimen part, Disease, Disease stage, Cell line
View SamplesThe MLL gene on chromosome 11 fuses to the AF6 gene on chromosome 6 in a balanced chromosomal translocation that is characetristic of certain adult and pediatric human leukemias. We established a murine leukemia model of MLL-AF6 using the retroviral MLL-AF6 contruct in a bone marrow transplantation system.
Leukemic transformation by the MLL-AF6 fusion oncogene requires the H3K79 methyltransferase Dot1l.
Specimen part, Disease, Disease stage
View SamplesThe MLL gene on chromosome 11 fuses to the AF6 gene on chromosome 6 in a balanced chromosomal translocation that is characetristic of certain adult and pediatric human leukemias. We established a murine leukemia model of MLL-AF6 using the retroviral MLL-AF6 contruct in a bone marrow transplantation system.
Leukemic transformation by the MLL-AF6 fusion oncogene requires the H3K79 methyltransferase Dot1l.
Disease, Disease stage, Cell line
View SamplesNAD(P)H:quinone Oxidoreductase (NQO1) is essential for cell defense against reactive oxidative species, cancer, and metabolic stress. Recently, NQO1 was found in ribonucleoprotein (RNP) complexes, but NQO1-interacting mRNAs and the functional impact of such interactions are not known. Here, we used ribonucleoprotein immunoprecipitation (RIP) and microarray analysis to identify comprehensively the subset of NQO1 target mRNAs in human hepatoma HepG2 cells. One of its main targets, SERPINA1 mRNA, encodes the serine protease inhibitor -1-antitrypsin, A1AT, which is associated with disorders including obesity-related metabolic inflammation, chronic obstructive pulmonary disease (COPD), liver cirrhosis and hepatocellular carcinoma. Biotin pulldown analysis indicated that NQO1 can bind the 3 untranslated region (UTR) and the coding region (CR) of SERPINA1 mRNA. NQO1 did not affect SERPINA1 mRNA levels; instead, it enhanced the translation of SERPINA1 mRNA, as NQO1 silencing decreased the size of polysomes forming on SERPINA1 mRNA and lowered the abundance of A1AT. Luciferase reporter analysis further indicated that NQO1 regulates SERPINA1 mRNA translation through the SERPINA1 3UTR. Accordingly, NQO1-KO mice had reduced hepatic and serum levels of A1AT and increased activity of neutrophil elastase, one of the main targets of A1AT. We propose that this novel mechanism of action of NQO1 as RNA-binding protein may help to explain its pleiotropic biological effects.
Novel RNA-binding activity of NQO1 promotes SERPINA1 mRNA translation.
Specimen part, Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
AF10 regulates progressive H3K79 methylation and HOX gene expression in diverse AML subtypes.
Specimen part, Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrated ordination of miRNA and mRNA expression profiles.
Specimen part
View SamplesSeveral studies have shown that negative and positive miRNA-mRNA correlations are symmetrically distributed. While negative correlations are consistent with a faster degradation of miRNA targets, the presence of positive correlations suggests bidirectional interactions between the two classes of molecules. However, a comprehensive study of miRNA and mRNA correlations is lacking. A homogeneous map of miRNA and mRNA relationships was obtained by multidimensional scaling (MDS) applied to a single matrix including both heterologous (miRNA-mRNA) and homologous (miRNA-miRNA and mRNA-mRNA) correlations.
Integrated ordination of miRNA and mRNA expression profiles.
Specimen part
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