This SuperSeries is composed of the SubSeries listed below.
c-Myc Antagonises the Transcriptional Activity of the Androgen Receptor in Prostate Cancer Affecting Key Gene Networks.
Cell line, Time
View SamplesProstate cancer is the most common non-cutaneous cancer in men. The androgen receptor (AR) a ligand-activated transcription factor, constitutes the main drug target for advanced cases of the disease. However, a variety of other transcription factors and signalling networks have been shown to be altered in patients and to influence AR activity. The oncogenic transcription factor c-Myc has been studied extensively in multiple malignancies, but its impact on AR activity in prostate cancer remains elusive. In this study we assessed the impact of clinically relevant levels of c-Myc overexpression on AR activity and transcriptional output. We found that c-Myc and the AR share a substantial amount of binding sites, which exhibit enhancer-like characteristics. Interestingly, c-Myc overexpression altered global AR chromatin occupancy and antagonised a subset of androgen-induced genes. Furthermore, c-Myc overexpression modified histone marks, most notably H3K4me1 and H3K27me3. Lastly, we validated the antagonistic relationship between c-Myc and two AR target genes, KLK3 and GNMT, in patient samples.
c-Myc Antagonises the Transcriptional Activity of the Androgen Receptor in Prostate Cancer Affecting Key Gene Networks.
Time
View SamplesThe level of trypsin-2 has been shown to correlate with the malignancy and metastatic potential of many cancer.
Trypsin-2 enhances carcinoma invasion by processing tight junctions and activating ProMT1-MMP.
Specimen part, Cell line
View SamplesThis work was conducted to identify shared and specific target genes of different ETS transcription factor rearrangements in prostate cancer. Potential target genes were identified by differential gene expression analysis of primary tumor samples with ETS rearrangements, and validated by ETS silencing in prostate cancer cell lines.
Molecular subtyping of primary prostate cancer reveals specific and shared target genes of different ETS rearrangements.
Specimen part
View SamplesProstate cancer is the most common male cancer and androgen receptor (AR) is the major driver of the disease. Here we show that Enoyl-CoA delta isomerase 2 (ECI2) is a novel AR-target that promotes prostate cancer cell survival. Increased ECI2 expression predicts mortality in prostate cancer patients (p=0.0086). ECI2 encodes for an enzyme involved in lipid metabolism, and we use multiple metabolite profiling platforms and RNA-seq to show that inhibition of ECI2 expression leads to decreased glucose utilization, accumulation of fatty acids and down-regulation of cell cycle related genes. In normal cells, decrease in fatty acid degradation is compensated by increased consumption of glucose, and here we demonstrate that prostate cancer cells are not able to respond to decreased fatty acid degradation. Instead, prostate cancer cells activate incomplete autophagy, which is followed by activation of the cell death response. Finally, we identified a clinically approved compound, perhexiline, which inhibits fatty acid degradation, and replicates the major findings for ECI2 knockdown. This work shows that prostate cancer cells require lipid degradation for survival and identifies a small molecule inhibitor with therapeutic potential. Overall design: Two biological replicates for prostate cancer cell line (LNCaP) and cell line representing normal prostate epithelium (RWPE-1), transfected with scrambled siRNA or two different siRNAs targeting ECI2. RNA was extracted and used for RNA-sequencing. The processed files provided are compressed folders containing multiple output files from CuffDiff runs estimating differentially expressed transcripts between the indicated ECI2 siRNA treated cells versus cells treated with Scrambled siRNAs.
Lipid degradation promotes prostate cancer cell survival.
No sample metadata fields
View SamplesAlternative mRNA splicing provides transcript diversity and has been proposed to contribute to several human diseases. Here, we demonstrate that expression of genes regulating RNA processing is decreased in both liver and skeletal muscle of obese humans. To determine the metabolic impact of reduced splicing factor expression, we further evaluated the splicing factor, SFRS10, identified as down-regulated in obese human liver and skeletal muscle and in high fat fed rodents. siRNA-mediated reductions in SFRS10 expression induced lipogenesis and lipid accumulation in cultured hepatocytes. Moreover, SFRS10 heterozygous mice have both increased hepatic lipogenic gene expression and hypertriglyceridemia. We also demonstrate that LPIN1, a key regulator of lipid metabolism, is a splicing target of SFRS10, with reduced SFRS10 levels favoring the lipogenic isoform of LPIN1. Importantly, LPIN1-specific siRNA abolished the lipogenic effects of decreased SFRS10 expression. Together, our results indicate reduced expression of SFRS10 alters LPIN1 splicing and induces lipogenesis, demonstrating that reduced splicing factor expression observed in human tissues may contribute to metabolic phenotypes associated with human obesity.
Expression of the splicing factor gene SFRS10 is reduced in human obesity and contributes to enhanced lipogenesis.
Age, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Androgen Receptor Deregulation Drives Bromodomain-Mediated Chromatin Alterations in Prostate Cancer.
Specimen part, Cell line, Time
View SamplesAltered patterns of transcription factor (TF) binding are now accepted as a hallmark of many aggressive cancers including prostate and breast cancers1,2. This implies that underlying global changes in chromatin accessibility may drive cancer progression, as previously hypothesized3-5. In addition there are epigenetic readers such as bromodomain containing protein 4 (BRD4), which have been shown to associate with these TFs6-8 and also to contribute to aggressive cancers of many types8,9 including prostate cancer (PC)6,10. Here we show for the first time that formaldehyde-assisted isolation of regulatory elements followed by sequencing (FAIRE-seq) applied to human prostate tumors tissue can define castrate-resistant prostate cancer (CRPC) and can be used to inform the discovery of gene-level classifiers for therapy. In addition, we show that the androgen receptor (AR) overexpression alone is a primary driver for chromatin relaxation and that this effect can be reversed using bromodomain inhibitors. We also report that bromodomain-containing proteins (BRDs) are overexpressed in advanced CRPCs and that ATAD2 and BRD2 have prognostic value. In conclusion, this is the first study demonstrating a major impact of BRDs on chromatin accessibility in CRPC in patient samples. Consequently, targeting bromodomains provides a compelling rational for combination therapy in which BRD-mediated TF binding is enhanced or modified as cancer progresses.
Androgen Receptor Deregulation Drives Bromodomain-Mediated Chromatin Alterations in Prostate Cancer.
Time
View SamplesT follicular helper CD4 T cells (Tfh) provide requisite help to B cells in the germinal centers (GC) of lymphoid tissue. GC Tfh are identified by high expression of the chemokine receptor CXCR5 and the inhibitory molecule PD-1. Although more accessible, blood contains lower frequencies of CXCR5+ and PD-1+ cells that have been termed circulating Tfh (cTfh). However, it remains unclear whether GC Tfh exit lymphoid tissues and populate this cTfh pool. To examine exiting cells, we assessed the phenotype of Tfh present within the major conduit of efferent lymph from lymphoid tissues into blood, the human thoracic duct. Unlike blood, we consistently identified a CXCR5-Bright PD-1-Bright (CXCR5BrPD-1Br) Tfh population in thoracic duct lymph (TDL). These CXCR5BrPD-1Br TDL Tfh shared phenotypic and transcriptional similarities with GC Tfh. Moreover, components of the epigenetic profile of GC Tfh could be detected in CXCR5BrPD-1Br TDL Tfh, and the transcriptional imprint of this epigenetic signature was enriched in an activated cTfh subset known to contain vaccine-responding cells. Together with data showing shared TCR sequences between the CXCR5BrPD-1Br TDL Tfh and cTfh, these studies identify a population in TDL as a circulatory intermediate connecting the biology of Tfh in blood to Tfh in lymphoid tissue. Overall design: Transcriptional features of germinal center Tfh were detected in a population of Tfh in the efferent lymph of the human thoracic duct and can be traced to an activated subset of circulating Tfh in blood.
T follicular helper cells in human efferent lymph retain lymphoid characteristics.
Specimen part, Subject
View Samples