Alternative splicing (AS) is a post-transcriptional gene regulatory mechanism that contributes to proteome diversity. Aberrant splicing mechanisms (mutations, polymorphisms, insertion/deletion etc.) contribute to various cancers and muscle related conditions such as Duchenne muscular dystrophy. However, dysregulation of AS in Cancer Cachexia (CC) patients remains unexplored. Our objectives were (i) to profile alternatively spliced genes (ASGs) on a genome-wide scale, and (ii) to identify DE alternatively spliced genes (DASGs) associated with CC. Rectus abdominis muscle biopsies obtained from cancer patients were stratified into cachectic cases (n=21, classified based on International consensus diagnostic framework for CC) and non-cachectic controls (n=19, weight stable cancer patients). Human Transcriptome array 2.0 was used for profiling ASGs using the total RNA isolated from muscle biopsies. Representative DASG signatures were validated using semi-quantitative RT-PCR. We identified 8960 ASGs, of which 922 DASGs (772 up-regulated, 150 down-regulated) were identified at > 1.4 fold-change and p < 0.05. Representative DASGs when validated by semi-quantitative RT-PCR also showed similar trends, confirming the primary findings from the genome-wide arrays. Identified DASGs were associated with myogenesis, adipogenesis, protein ubiquitination and inflammation. Up to 10% of the DASGs exhibited cassette exon (exon included or skipped) as a predominant form of AS event. We also observed other forms of AS events such as intron retention, alternate promoters. Overall, we have, for the first time conducted global profiling of muscle tissue to identify DASGs associated with CC. The mechanistic roles of the identified DASGs in CC pathophysiology using model systems is warranted, as well as replication of findings in independent cohorts.
Small RNAome profiling from human skeletal muscle: novel miRNAs and their targets associated with cancer cachexia.
Specimen part
View SamplesThe H2A variant H2AZ is essential for embryonic development and for proper execution of developmental gene expression programs in embryonic stem cells (ESCs). Divergent regions in H2AZ are likely key for its functional specialization, but we know little about how these differences contribute to chromatin regulation. Here, we show that the extended acidic patch, specifically the three divergent residues in the C-terminal docking domain, is necessary for lineage commitment during ESC differentiation and proper execution of gene expression programs during ESC differentiation. Surprisingly, disruption of the acidic patch domain has a distinct consequence on cellular specification compared to H2AZ depletion. This is consistent with differences in gene expression profiles of H2AZ –depleted and acidic patch (AP) mutant ESCs during early lineage commitment. Interestingly, the distinct consequence of AP mutant expression on gene regulation is coincidence with an altered destabilized chromatin state and high chromatin mobility dependent on active transcription. Collectively, our data shows that the divergent residues within the acidic patch domain are key structural determinants of H2AZ function and links chromatin structure and dynamics with gene regulation and cell fate specification. Overall design: H2AZ extended acidic patch was mutated, or H2AZ was KD in mouse embryonic stem cells and RNA-Seq analysis was performed on the resulting cultures. Characterization of H2AZ-WT and -AP3-mutant binding specificities were performed by ChIP-Seq.
H2A.Z acidic patch couples chromatin dynamics to regulation of gene expression programs during ESC differentiation.
Specimen part, Cell line, Subject, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Estrogen Receptor α Promotes Breast Cancer by Reprogramming Choline Metabolism.
Specimen part, Cell line
View SamplesEstrogen receptor (ER) is a key regulator of breast growth and breast cancer development. However, the role of ER in metabolic reprogramming, a hallmark of cancer, is not well documented. In this study, using an integrated approach combining genome-wide mapping of chromatin bound ER with estrogen induced transcript and metabolic profiling, we demonstrate that ER reprograms metabolism upon estrogen stimulation, including changes in aerobic glycolysis, nucleotide and amino acid synthesis, and choline metabolism. We show, for the first time, that the ER target gene choline phosphotransferase 1 (CHPT1) plays an essential role in estrogen induced increases in phosphatidylcholine (PtdCho) levels and that CHPT1 promotes tumorigenesis and proliferation. Furthermore, we show that CHPT1 is overexpressed in tumors compared to normal breast. We also demonstrate that ER promotes aerobic glycolysis through increased expression of glycolytic genes. In conclusion, this study highlights the importance of ER for metabolic alterations in breast cancer cells. Furthermore, overexpression of the ER target CHPT1 in breast cancer supports its potential as a therapeutic target.
Estrogen Receptor α Promotes Breast Cancer by Reprogramming Choline Metabolism.
Specimen part, Cell line
View SamplesIsoniazid induced varying degrees of hepatic steatosis in an inbred strain Mouse Diversity Panel (MDP) study. RNA was isolated from all animals for analysis of gene expression changes in the liver. The objective of this study was to identify gene expression changes that drive isoniazid-induced steatosis.
A systems biology approach utilizing a mouse diversity panel identifies genetic differences influencing isoniazid-induced microvesicular steatosis.
Sex, Specimen part, Treatment
View SamplesMicroarray analysis was used to compare the gene expression profiles of Deaf-1-transduced mouse mammary epithelial cells (MECs) relative to Deaf-1-deficient MECs.
Deaf-1 regulates epithelial cell proliferation and side-branching in the mammary gland.
No sample metadata fields
View SamplesBone morphogenetic proteins (BMP) are firmly implicated as intra-ovarian regulators of follicle development and steroidogenesis. We carried out a microarray analysis to examine global changes in gene expression in bovine theca cells in response to treatment with BMP6 alone and in combination with LH. There was a major effect of BMP6 treatment on the gene expression profile with a much weaker effect of LH. None of these differences in response to LH treatment was found to be statistically significant after applying Benjamini-Hochberg correction. BMP6 significantly (>2-fold; P<0.01) up- or down-regulated expression of 445 genes. Insulin-like peptide 3 (INSL3) was the most heavily down-regulated gene (-43-fold) with CYP17A1 and other key transcripts involved in TC steroidogenesis including LHCGR, INHA, STAR, CYP11A1 and HSD3B1 also down-regulated. BMP6 also reduced expression of NR5A1 encoding steroidogenic factor-1 known to target the promoter regions of the aforementioned genes. Real-time PCR confirmed these findings and also revealed a marked reduction in expression of INSL3 receptor (RXFP2). Secretion of INSL3 protein and androstenedione were also suppressed suggesting a functional link between BMP and INSL3 pathways in controlling androgen synthesis.
Functional link between bone morphogenetic proteins and insulin-like peptide 3 signaling in modulating ovarian androgen production.
Specimen part
View SamplesStudy of HP1 Knock Down on gene expression and splicing regulation in Human HeLa cells
Histone H3 lysine 9 trimethylation and HP1γ favor inclusion of alternative exons.
Cell line
View SamplesMYC is a pleiotropic transcription factor that regulates numerous pathways and whose deregulation promotes cancer. Myc+/- mice have extended lifespan relative to their wild type littermates. To better understand the effects of the Myc+/- genotype on cellular processes, microarrays were performed on young (5 month) and old (24 month) Myc+/- and WT males in liver, skeletal muscle, and adipose tissues.
Reduced expression of MYC increases longevity and enhances healthspan.
Sex, Age, Specimen part
View SamplesThe whole blood was collected pre-treatment from rheumatoid arthritis patients starting the anti_TNF therapy. All patients were nave to anti_TNFs. The disease activity was measured using the DAS28 score at the pre-treatment visit1 (DAS28_v1) and 14 weeks after treatment visit3 (DAS28_v3). The response to the therapy was evaluated using the EULAR [European League Against Rheumatism] definition of the response. The objective of the data analysis was to identify gene expression coorelating with response as well as to identify genes that differentiate responders versus non-responders pre-treatment. The results of this investigation identified 8 trainscripts that predict responders vs. non-responders with 89% accuracy.
Convergent Random Forest predictor: methodology for predicting drug response from genome-scale data applied to anti-TNF response.
Specimen part, Disease, Disease stage
View Samples