The androgen receptor induces a distinct transcriptional program in castration resistant prostate cancer in man
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE28219 | GEO | 2013/01/04
SECONDARY ACCESSION(S): PRJNA139671
REPOSITORIES: GEO
Similar Datasets
Project description:The androgen receptor (AR) is the major transcriptional driver of prostate cell growth in man. For the first time, we define AR targets in prostate cancer (PC) tissue representing progression from treatment-naive to castrate-resistant disease (CRPC). We employed chromatin immunoprecipitation with high through-put sequencing (ChIP-seq) in human tissue, with cell-line and xenograft studies. We uncovered an AR transcriptional network not observed in cultured cells, with significant over-representation of MYC, E2F and STAT binding sites, progenitor cell gene signatures and targets which regulate metabolism, cell cycle and steroid biosynthesis. We identified AR targets unique to CRPC tissue, with a subset over-expressed in CRPC and predictive of clinical outcome, highlighting persistence of AR signalling. Our data support a model whereby endocrine and paracrine signals converge on the AR in PC tissue to drive oncogenic transcriptional programs, highlighting the critical role of cellular context in the regulation of target selection and gene expression. chromatin immunoprecipitation with high through-put sequencing (ChIP-seq) in human tissue, with cell-line and xenograft studies
2013-01-04 | E-GEOD-28219 | biostudies-arrayexpress
Project description:Characterization of the prostate cancer transcriptome and genome has identified chromosomal rearrangements and copy number gains/losses, including ETS gene fusions, PTEN loss and androgen receptor (AR) amplification, that drive prostate cancer development and progression to lethal, metastatic castrate resistant prostate cancer (CRPC)1. As less is known about the role of mutations2-4, here we sequenced the exomes of 50 lethal, heavily-pretreated metastatic CRPCs obtained at rapid autopsy (including three different foci from the same patient) and 11 treatment naïve, high-grade localized prostate cancers. We identified low overall mutation rates even in heavily treated CRPC (2.00/Mb) and confirmed the monoclonal origin of lethal CRPC. Integrating exome copy number analysis identified disruptions of CHD1, which define a subtype of ETS? prostate cancer. Similarly, we demonstrate that ETS2, which is deleted in ~1/3 of CRPCs (commonly through TMPRSS2:ERG fusions), is a prostate cancer tumor suppressor that can also be deregulated through mutation. Further, we identified recurrent mutations in multiple chromatin/histone modifying genes, including MLL2 (mutated in 8.6% of prostate cancers), and demonstrate interaction of the MLL complex with AR, which is required for AR mediated signaling. We also identified novel recurrent mutations in the AR collaborating factor FOXA1, which is mutated in 5 of 147 (3.4%) prostate cancers (both untreated localized prostate cancer and CRPC) , and showed that mutated FOXA1 represses androgen signaling and increases tumor growth in vitro and in vivo. Proteins that physically interact with AR, such as the ERG gene fusion product, FOXA1, MLL2, UTX, and ASXL1 were found to be mutated in CRPC, suggesting novel drivers of prostate cancer progression and potential resistance mechanisms to anti-androgen therapies. In summary, we describe the mutational landscape of a heavily treated metastatic cancer, identify novel mechanisms of AR signaling deregulated in prostate cancer, and prioritize candidates for future study. Gene expression profiling and array CGH (aCGH) was performed on matched benign prostate tissues (n=28), localized prostate cancer (n=59), and metastatic castrate resistant prostate cancer (CRPC, n=35). For gene expression profiling, frozen prostate tissue samples (channel 2), were hybridized against a commercial pool of benign prostate tissue (Clontech, channel 1). For aCGH, frozen prostate tissue samples (channel 2) were hybridized against a commerical sample of Human Male Genomic DNA (Promega, channel 1).
2012-05-22 | E-GEOD-35988 | biostudies-arrayexpress
Project description:Castrate-resistant prostate cancer (CRPC) is poorly characterized and heterogeneous and while the androgen receptor (AR) is of singular importance in early prostate cancer, other factors such as c-Myc and the E2F family also play a role in later stage disease. Hes6 is a transcription co-factor that has been associated with neurogenesis during gastrulation, a neuroendocrine phenotype in the prostate and metastasis in breast cancer but its role in prostate cancer remains uncertain. Here we show that Hes6 is controlled by c-Myc and AR and drives castration resistance in prostate cancer. Hes6 activates a cell-cycle enhancing transcriptional network that maintains tumour growth and nuclear AR localization in castrate conditions. We show aphysical interaction between E2F1 and both Hes6 and AR, and suggest a co-dependency of these transcription factors in castration-resistance. In the clinical setting, we have uncovered a Hes6-associated signature that predicts poor outcome in prostate cancer, which can be pharmacologically targeted. We have therefore shown for the first time the critical role of Hes6 in the development of CRPC and identified its potential in patient specific therapeutic strategies. This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-04-17 | E-GEOD-36526 | biostudies-arrayexpress
Project description:The androgen receptor (AR) is a key driver of prostate cancer (PC), even in the state of castration-resistant PC (CRPC), and frequently even after treatment with second-line hormonal therapies such as abiraterone and enzalutamide. The persistence of AR activity via both ligand-dependent and ligand-independent (including constitutively active AR splice variants) mechanisms highlights the unmet need for alternative approaches to block AR signaling in CRPC. We investigated the transcription factor GATA2 as a regulator of AR signaling and a novel therapeutic target in PC. We demonstrate that GATA2 directly promotes AR expression (both full-length and splice variant), resulting in a strong positive correlation between GATA2 and AR expression in PC (cell lines and patient specimens). Conversely, GATA2 expression is repressed by androgen and AR, suggesting a negative feedback regulatory loop that, upon androgen deprivation, derepresses GATA2 to contribute to AR overexpression in CRPC. Simultaneously, GATA2 is necessary for optimal transcriptional activity of AR (both full-length and splice variant). GATA2 co-localizes with AR and FOXA1 on chromatin to enhance recruitment of steroid receptor coactivators (SRCs) and formation of the transcriptional holocomplex. In agreement with these important functions, high GATA2 expression and transcriptional activity predicted for worse clinical outcome in PC patients. A GATA2 small molecule inhibitor suppressed the expression and transcriptional function of AR (both full-length and splice variant) and exerted potent anticancer activity against PC cell lines. We propose pharmacological inhibition of GATA2 as a “first-in-field” approach to target AR expression and function and improve outcomes in CRPC. LNCaP cells were transfected with control siRNA (3), GATA2 siRNA (3) or AR siRNA for 72 hours.
2015-01-21 | E-GEOD-63539 | biostudies-arrayexpress
Project description:Altered 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. FAIRE-seq study for LNCaP and VCaP prostate cancer cell lines hormone starved or treated with R1881, and human prostate tissue samples from benign prostate hyperplasia (BPH), primary prostate cancer (PC), and castrate resistant prostate cancer (CRPC) patients.
2017-06-06 | GSE73988 | GEO
Project description:In prostate cancer, the androgen receptor (AR) is a key transcription factor at all disease stages. We recently showed that during progression to castrate-resistant prostate cancer the AR acquires the ability to bind to a distinct set of genomic sites in tissue samples and that some of the genes that are regulated by the AR in these conditions correlate with poor prognosis. Based on this work we hypothesised that the AR is reprogrammed through interactions with other transcription factors. In the present study we show that GABPá, an ETS transcription factor which is upregulated in CRPC, is an AR-interacting transcription factor. Ectopic expression of GABPA in prostate cancer cell-lines enables them to acquire some of the molecular and cellular characteristics of CRPC tissues as well as more aggressive growth phenotypes. VCaP prostate cancer cells and Jurkat lymphoma cells were studied for the ETS factors ERG and GABPa binding sites. Each sample was compared to its input.
2014-05-21 | E-GEOD-49091 | biostudies-arrayexpress
Project description:The development and progression of castrate resistant prostate cancer (CRPC), a lethal disease, is thought to be driven by multiple events. A hallmark of CRPC is the ability to evade the cytotoxic effects of anti-androgen therapy. Importantly, persistent androgen receptor (AR) signalling is thought to play a principal role in maintaining CRPC. The precise molecular alterations driving this condition, however, are not clearly understood. Our previous studies identified specific metabolic alterations associated with localized prostate cancer (PCa) and CRPC, implicating metabolic re-programming in disease progression. Building on these findings, using a novel network-based integromics approach, here we show distinct alterations in the Hexosamine Biosynthetic Pathway (HBP) to be critical for sustaining the castrate resistant state. We found expression of the HBP enzyme glucosamine-phosphate N-acetyltransferase 1 (GNPNAT1) was regulated by androgens and elevated in androgen dependent (AD) PCa while relatively diminished in CRPC possessing either full length AR (AR-FL) or the spliced V7 variant (AR-V7). Genetic loss of function experiments for GNPNAT1 in CRPC-like cells led to increased proliferation and aggressiveness, both, in vitro and in vivo. This was mediated by specific cell cycle genes regulated by the PI3K-AKT pathway activating either AR in cells with AR-FL or SP1-ChREBP (carbohydrate response element binding protein) in cells containing AR-V7. Strikingly, addition of HBP metabolite UDP-N-acetylglucosamine (UDP) to CRPC-like cells reduced the expression of cell cycle genes and attenuated tumor cell proliferation, both in vitro and in vivo. Furthermore, addition of UDP sensitized CRPC-like cells, inclusive of those possessing AR-V7, to enzalutamide, demonstrating the therapeutic value of targeting altered metabolic pathways in lethal PCa. We anticipate that our findings will motivate the development of novel metabolic therapeutic strategies that complement existing treatments for men with lethal prostate cancer We used microarray analysis to determine key molecular alterations associated with inhibition of HBP pathway in CRPC by knocking down GNPNAT1 transcript level using lentiviral particle bearing shRNA in 22Rv1 and LNCaP-ABL cells GNPNAT1 expression was knockdown in two independent prostate cancer cells, 22Rv1 and LNCaP-ABL
2015-04-03 | E-GEOD-67537 | biostudies-arrayexpress
Project description:In prostate cancer, the androgen receptor (AR) is a key transcription factor at all disease stages. We recently showed that during progression to castrate-resistant prostate cancer the AR acquires the ability to bind to a distinct set of genomic sites in tissue samples and that some of the genes that are regulated by the AR in these conditions correlate with poor prognosis. Based on this work we hypothesised that the AR is reprogrammed through interactions with other transcription factors. In the present study we show that GABPá, an ETS transcription factor which is upregulated in CRPC, is an AR-interacting transcription factor. Ectopic expression of GABPA in prostate cancer cell-lines enables them to acquire some of the molecular and cellular characteristics of CRPC tissues as well as more aggressive growth phenotypes.
2014-05-21 | GSE49091 | GEO
Project description:In prostate cancer, the androgen receptor (AR) is a key transcription factor at all disease stages. We recently showed that during progression to castrate-resistant prostate cancer the AR acquires the ability to bind to a distinct set of genomic sites in tissue samples and that some of the genes that are regulated by the AR in these conditions correlate with poor prognosis. Based on this work we hypothesised that the AR is reprogrammed through interactions with other transcription factors. In the present study we show that GABPá, an ETS transcription factor which is upregulated in CRPC, is an AR-interacting transcription factor. Ectopic expression of GABPA in prostate cancer cell-lines enables them to acquire some of the molecular and cellular characteristics of CRPC tissues as well as more aggressive growth phenotypes.
2014-05-21 | GSE49083 | GEO
Project description:In prostate cancer, the androgen receptor (AR) is a key transcription factor at all disease stages. We recently showed that during progression to castrate-resistant prostate cancer the AR acquires the ability to bind to a distinct set of genomic sites in tissue samples and that some of the genes that are regulated by the AR in these conditions correlate with poor prognosis. Based on this work we hypothesised that the AR is reprogrammed through interactions with other transcription factors. In the present study we show that GABPá, an ETS transcription factor which is upregulated in CRPC, is an AR-interacting transcription factor. Ectopic expression of GABPA in prostate cancer cell-lines enables them to acquire some of the molecular and cellular characteristics of CRPC tissues as well as more aggressive growth phenotypes. Cells were made to either overexpress GABPa or have it knocked down; these conditions also had empty vector and non-targetting controls respectively. All four treatments were carried out with and without androgen for the LNCaP and c42b cell lines. Biological and technical replicates were used.
2014-05-21 | E-GEOD-49083 | biostudies-arrayexpress