Skeletal muscle myofibers accrue hundreds of nuclei during post-natal development via fusion with activated satellite cells (myoblasts), which is absolutely reliant on expression of the muscle fusogen myomaker (Mymk) in the myoblasts. Using an inducible genetic approach to render myoblasts non-fusogenic (by tamoxifen-inducible Pax7-CreER mediated recombination of the Mymk gene exclusively in satellite cells), we blocked myonuclear accrual at different time-points of post-natal development and thereby titrated the number of nuclei in resultant mutant myofibers. These Microarray assays were carried out on age day 28 (P28) using total RNA isolated from control and mutant muscle to determine changes in transcriptional profiles of these muscles to (a) assess effects of myonuclear titration, and (b) identify adaptive mechanisms elicited in mutant muscles in response to myonuclear deficiency.
Nuclear numbers in syncytial muscle fibers promote size but limit the development of larger myonuclear domains.
Specimen part
View SamplesLineage plasticity is a major mechanism driving prostate cancer progression and antiandrogen therapy resistance. Deletions or mutations in phosphatase and tensin homolog (PTEN) and TP53 tumor suppressor genes have been linked to lineage plasticity in prostate cancer. Fusion-driven overexpression of the E-twenty-six transformation specific (ETS)-related gene (ERG), encoding an oncogenic transcription factor, is observed in approximately 50% of all prostate cancers, yet its role in prostate cell lineage determination remains elusive. Here we demonstrate that transgenic expression of prostate cancer-associated ERG blocks Pten and Trp53 mutation-induced decreased expression of Ar and its downstream target genes and loss of luminal epithelial cell identity in the mouse prostate. Integrative analyses of ERG chromatin-immunoprecipitation sequencing (ChIP-seq) and transcriptome data show that ERG suppresses expression of a subset of cell cycle-promoting genes and RB phosphorylation, which in turn causes repression of E2F1-mediated expression of non-epithelial lineage genes. Xenograft studies show that PTEN/TP53 double mutated prostate tumors are responsive to the cyclin-dependent kinase 4 or 6 (CDK4/6) inhibitor palbociclib, but resistant to the AR inhibitor enzalutamide, while ERG/PTEN/TP53 triple-mutated prostate tumors behave completely opposite. Our studies identify ERG and the repressed cell cycle gene signature as intrinsic inhibitors of PTEN/TP53 double mutation-elicited lineage plasticity in prostate cancer. Our findings also suggest that ERG fusion can be utilized as a biomarker to guide the treatment of PTEN/TP53-mutated, RB1-intact prostate cancer with either antiandrogen or anti-CDK4/6 therapies. Overall design: Prostate tissue from mice with 1) prostate specific PTEN deletion, p53 R172H mutation with loss of heterozygosity, or 2) prostate specific PTEN deletion, p53 R172H mutation with loss of heterozygosity and transgenic ERG expression were harvested at 4-5 months. RNA was isolated from tissue and RNA-seq experiments were then performed for both genotype samples in triplicates. Differentially expressed genes were identified by comparing genotype #1 and genotype #2.
<i>TMPRSS2-ERG</i> Controls Luminal Epithelial Lineage and Antiandrogen Sensitivity in <i>PTEN</i> and <i>TP53</i>-Mutated Prostate Cancer.
Specimen part, Subject
View SamplesCell migration contributes to normal development and homeostasis as well as to pathological processes such as inflammation and tumor metastasis. Previous genetic screens have revealed a few major signaling pathways that govern follicle cell migrations in the Drosophila ovary, several of which elicit transcriptional responses. However few downstream targets of the critical transcriptional regulators, such as the C/EBP homolog SLBO, have been identified. To characterize the gene expression profile of two migratory cell populations and identify SLBO targets, we employed a magnetic bead based cell separation approach to purify border cells and centripetal cells expressing the mouse CD8 antigen, and carried out whole genome microarray analysis.
Analysis of cell migration using whole-genome expression profiling of migratory cells in the Drosophila ovary.
Sex, Specimen part
View SamplesDifferential gene expression analysis of oesophageal cells stimulated with a low pH environment. Study designed to identify pathways involved in progression of gastro-oesophageal reflux disease through Barrett's oesophagus to adenocarcinoma. Identified many subsets of genes with involvement in pathogenesis.
Low pH induces co-ordinate regulation of gene expression in oesophageal cells.
No sample metadata fields
View SamplesHistone modifications are a key epigenetic mechanism to activate or repress the expression of genes. Data sets of matched microarray expression data and histone modification data measured by ChIP-seq exist, but methods for integrative analysis of both data types are still rare. Here, we present a novel bioinformatic approach to detect genes that are differentially expressed between two conditions putatively caused by alterations in histone modification. We introduce a correlation measure for integrative analysis of ChIP-seq and gene expression data and demonstrate that a proper normalization of the ChIP-seq data is crucial. We suggest applying Bayesian mixture models of different distributions to further study the distribution of the correlation measure. The implicit classification of the mixture models is used to detect genes with differences between two conditions in both gene expression and histone modification. The method is applied to different data sets and its superiority to a naive separate analysis of both data types is demonstrated. This GEO series contains the expression data of the Cebpa example data set.
Integrative analysis of histone ChIP-seq and transcription data using Bayesian mixture models.
No sample metadata fields
View SamplesAcute myeloid leukemia (AML) is a heterogeneous disease and AML with normal karyotype (AML-NK) is categorized as an intermediate-risk group. Over the past years molecular analyses successfully identified biomarkers that will further allow to dissecting clinically meaningful subgroups in this disease. Thus far, somatic mutations were identified which elucidate the disturbance of cellular growth, proliferation, and differentiation processes in hematopoietic progenitor cells. In AML-NK, acquired gene mutations with prognostic relevance were identified for FLT3, CEBPA, and NPM1. FLT3-ITD mutations were associated with short relapse-free and overall survival, while mutations in CEBPA or NPM1 (without concomitant FLT3-ITD) had a more favorable outcome.
Quantitative comparison of microarray experiments with published leukemia related gene expression signatures.
Sex, Age, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
An integrative genomic approach in oesophageal cells identifies TRB3 as a bile acid responsive gene, downregulated in Barrett's oesophagus, which regulates NF-kappaB activation and cytokine levels.
No sample metadata fields
View SamplesExpression profiling of 3T3-F442A adipocytes treated with growth hormone (GH, 500 nM) or vehicle (DMEM + 1% BSA) control for 30 min., 4 hr., or 48 hr in three independent experiments. Chronic GH treatment induces metabolic changes consistent with insulin resistance in 3T3-F442A adipocytes.
Profiles of growth hormone (GH)-regulated genes reveal time-dependent responses and identify a mechanism for regulation of activating transcription factor 3 by GH.
No sample metadata fields
View SamplesThe involvment of bile acids such as deoxycholic acid (DCA) in gastro-esophageal reflux disease and subsequent Barretts metaplsia has been postulated. This study examines gene expression induced by exposure to DCA in esophageal cells and may be utilised in cross-comparisons with data derived from gene expression studies of Barretts esophagus and associated adenocarcinoma.
An integrative genomic approach in oesophageal cells identifies TRB3 as a bile acid responsive gene, downregulated in Barrett's oesophagus, which regulates NF-kappaB activation and cytokine levels.
No sample metadata fields
View SamplesThe involvment of bile acids such as deoxycholic acid (DCA) in gastro-esophageal reflux disease and subsequent Barretts metaplsia has been postulated. This study examines gene expression induced by exposure to DCA in esophageal cells and may be utilised in cross-comparisions with data derived from gene expression studies of Barretts esophagus and associated adenocarcinoma. Additionally this study may be used to assess divergence in response to bile acids by comparisons with similar study performed in SKGT4 barrett''s assocaited adenocarcinoma cell line.
An integrative genomic approach in oesophageal cells identifies TRB3 as a bile acid responsive gene, downregulated in Barrett's oesophagus, which regulates NF-kappaB activation and cytokine levels.
No sample metadata fields
View Samples