Androgen receptor gene aberrations in circulating cell-free DNA: biomarkers of therapeutic resistance and response in castration-resistant prostate cancer
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE61134 | GEO | 2015/03/09
SECONDARY ACCESSION(S): PRJNA260306
REPOSITORIES: GEO
Similar Datasets
Project description:aCGH experiment on cell-free DNA collected from the plasma of patients with castration-resistant prostate cancer. No replicates. castration-resistant prostate cancer vs male reference DNA
2015-03-09 | E-GEOD-61134 | biostudies-arrayexpress
Project description:Androgen receptor (AR) splice variants (SV) have been implicated in the development of metastatic castration-resistant prostate cancer and resistance to AR targeting therapies, including abiraterone and enzalutamide. Agents targeting AR-SV are urgently needed to test this hypothesis and further improve the outcome of patients suffering from this lethal disease. Clin Cancer Res; 22(17); 4280-2. ©2016 AACRSee related article by Yang et al., p. 4466.
| S-EPMC5302169 | biostudies-literature
Project description:The therapeutic landscape of castration-resistant prostate cancer (CRPC) has rapidly expanded. There is a need to develop noninvasive biomarkers to guide treatment. We established a highly sensitive method for analyzing androgen receptor gene (AR) copy numbers (CN) and mutations in plasma circulating cell-free DNA (cfDNA) and evaluated the AR statuses of patients with CRPC. AR amplification was detectable in VCaP cell line (AR amplified) genomic DNA (gDNA) diluted to 1.0% by digital PCR (dPCR). AR mutation were detectable in LNCaP cell line (AR T878A mutated) gDNA diluted to 0.1% and 1.0% by dPCR and target sequencing, respectively. Next, we analyzed AR status in cfDNA from 102 patients. AR amplification and mutations were detected in 47 and 25 patients, respectively. As a biomarker, AR aberrations in pretreatment cfDNA were associated with poor response to abiraterone, but not enzalutamide. In serial cfDNA analysis from 41 patients, most AR aberrations at baseline diminished with effective treatments, whereas in some patients with disease progression, AR amplification or mutations emerged. The analysis of AR in cfDNA is feasible and informative procedure for treating patients with CRPC. cfDNA may become a useful biomarker for precision medicine in CRPC.
| S-EPMC6411952 | biostudies-literature
Project description:The number of circulating tumor cells (CTCs) in metastatic prostate cancer patients provides prognostic and predictive information. However, it is the molecular characterization of CTCs that offers insight into the biology of these tumor cells in the context of personalized treatment. We performed a pilot study to evaluate the feasibility of isolation and genomic profiling of CTCs in castration-resistant prostate cancer. CTCs in 7.5 mLs of blood in 20 castration-resistant metastatic prostate cancer patients were enumerated using CellSearch. Additional 10-20 mLs of blood from 12 patients positive for CTCs were subjected to immunomagnetic enrichment and fluorescence activated cell sorting (IE/FACS) to isolate pools of ~20 CTCs. Genomic DNA of CTCs was subjected to whole genome amplification followed by gene copy number analysis via array comparative genomic hybridization (aCGH). Archival primary tumor biopsy samples available from 2 patients were also subjected to aCGH.
2012-03-08 | GSE27636 | GEO
Project description:Relatively little is known about how changes in gene copy number (CN) and gene CpG methylation interact to affect specific pathways in metastatic castration-resistant prostate cancer (CRPC). Oligonucleotide array comparative genomic hybridization (aCGH) was performed on DNA isolated from 15 metastatic CRPC samples. Commonly aberrant genes were evaluated in a confirmatory fashion using PCR, aCGH data from primary tumors, and existing CRPC expression data. Array-based comprehensive CpG methylation was assessed on the same sample set. A total of 495 genes (79 gained, 416 deleted) were CN aberrant in ?66% of the samples by aCGH, and 77 (9 amplified, 68 deleted) had statistically concordant expression including gain of AR and loss of PTEN and RB1. Significant CN differences were seen between the genomes of patients with AR-amplified and AR-unamplified tumors, including common loss of AR repressors in AR-unamplified tumors. The majority of CRPC samples were hypermethylated compared to benign prostate tissue. Simultaneous methylation and heterozygous gene deletion occurred in the tumor suppressor RB1 and in HSD17B2, responsible for testosterone metabolism. Establishment of a comprehensive methylation signature and coupling of epigenomic and structural analyses sheds light on the alterations that allow CRPC to circumvent hormonal therapy and may provide new drug targets for what is currently an incurable disease state. 15 tumor samples taken from 14 men with metastatic castration resistant prostate cancer were analyzed, including two samples from the same patient. No control samples were used for this experiment.
2011-12-06 | E-GEOD-34174 | biostudies-arrayexpress
Project description:The androgen receptor (AR) is overexpressed and hyperactivated in human castration-resistant prostate cancer (CRPC). However, the determinants of AR overexpression in CRPC are poorly defined. Here we show that retinoic acid receptorârelated orphan receptor γ (ROR-γ) is overexpressed and amplified in metastatic CRPC tumors, and that ROR-γ drives AR expression in the tumors. ROR-γ recruits nuclear receptor coactivator 1 and 3 (NCOA1 and NCOA3, also known as SRC-1 and SRC-3) to an ARâROR response element (RORE) to stimulate AR gene transcription. ROR-γ antagonists suppress the expression of both AR and its variant AR-V7 in prostate cancer (PCa) cell lines and tumors. ROR-γ antagonists also markedly diminish genome-wide AR binding, H3K27ac abundance and expression of the AR target gene network. Finally, ROR-γ antagonists suppressed tumor growth in multiple AR-expressing, but not AR-negative, xenograft PCa models, and they effectively sensitized CRPC tumors to enzalutamide, without overt toxicity in mice. Taken together, these results establish ROR-γ as a key player in CRPC by acting upstream of AR and as a potential therapeutic target for advanced PCa. A total of 16 samples were analyzed in this study. The study included one cell line C4-2B. C4-2B cells were cultured in medium containing vehicle control or SR2211 (5 µM) for 24 hours, cells then were collected for ChIP seq assay
2016-03-08 | E-GEOD-72714 | biostudies-arrayexpress
Project description:The androgen receptor (AR) is overexpressed and hyperactivated in human castration-resistant prostate cancer (CRPC). However, the determinants of AR overexpression in CRPC are poorly defined. Here we show that retinoic acid receptorârelated orphan receptor γ (ROR-γ) is overexpressed and amplified in metastatic CRPC tumors, and that ROR-γ drives AR expression in the tumors. ROR-γ recruits nuclear receptor coactivator 1 and 3 (NCOA1 and NCOA3, also known as SRC-1 and SRC-3) to an ARâROR response element (RORE) to stimulate AR gene transcription. ROR-γ antagonists suppress the expression of both AR and its variant AR-V7 in prostate cancer (PCa) cell lines and tumors. ROR-γ antagonists also markedly diminish genome-wide AR binding, H3K27ac abundance and expression of the AR target gene network. Finally, ROR-γ antagonists suppressed tumor growth in multiple AR-expressing, but not AR-negative, xenograft PCa models, and they effectively sensitized CRPC tumors to enzalutamide, without overt toxicity in mice. Taken together, these results establish ROR-γ as a key player in CRPC by acting upstream of AR and as a potential therapeutic target for advanced PCa. A total of 6 samples were analyzed in this study. The study included one cell line C4-2B. C4-2B cells were cultured in medium containing vehicle control and/or SR2211 and/or XY011 and/or Enzalutamide (ENZ). The untreated C4-2B cells served as controls for the study.
2016-03-08 | E-GEOD-72483 | biostudies-arrayexpress
Project description:The androgen receptor (AR) is a ligand-inducible transcription factor that mediates androgen action in target tissues. Upon ligand binding, the AR binds to thousands of genomic loci and activates a cell-type specific gene program. Prostate cancer growth and progression depend on androgen-induced AR signalling. Treatment of advanced prostate cancer through medical or surgical castration leads to initial response and durable remission, but resistance inevitably develops. In castration-resistant prostate cancer (CRPC), AR activity remains critical for tumor growth despite androgen deprivation. While previous studies have focused on ligand-dependent AR signalling, in this study we explore AR function under the androgen-deprived conditions characteristic of CRPC. Our data demonstrate that the AR persistently occupies a distinct set of genomic loci after androgen deprivation in CRPC. These androgen-independent AR occupied regions have constitutively open chromatin structures that lack the canonical androgen response element and are independent of FoxA1, a transcription factor involved in ligand-dependent AR targeting. Many AR binding events occur at proximal promoters, which can act as enhancers to augment transcriptional activities of other promoters through DNA looping. We further show that androgen-independent AR binding directs a distinct gene expression program in CRPC, which is necessary for the growth of CRPC after androgen withdrawal. LNCaP, C4-2B, or 22RV1 cells were cultured in hormone-free media for 3 days and then treated with ethanol vehicle or DHT (10nM) for 4h or 16h prior to ChIP-seq or RNA-seq assays. For siRNA transfection, cells were transfected with AR siRNA or control siRNA for 3 days prior to RNA-seq assays.
2012-10-02 | E-GEOD-40050 | biostudies-arrayexpress
Project description:Relatively little is known about how changes in gene copy number (CN) and gene CpG methylation interact to affect specific pathways in metastatic castration-resistant prostate cancer (CRPC). Oligonucleotide array comparative genomic hybridization (aCGH) was performed on DNA isolated from 15 metastatic CRPC samples. Commonly aberrant genes were evaluated in a confirmatory fashion using PCR, aCGH data from primary tumors, and existing CRPC expression data. Array-based comprehensive CpG methylation was assessed on the same sample set. A total of 495 genes (79 gained, 416 deleted) were CN aberrant in ≥66% of the samples by aCGH, and 77 (9 amplified, 68 deleted) had statistically concordant expression including gain of AR and loss of PTEN and RB1. Significant CN differences were seen between the genomes of patients with AR-amplified and AR-unamplified tumors, including common loss of AR repressors in AR-unamplified tumors. The majority of CRPC samples were hypermethylated compared to benign prostate tissue. Simultaneous methylation and heterozygous gene deletion occurred in the tumor suppressor RB1 and in HSD17B2, responsible for testosterone metabolism. Establishment of a comprehensive methylation signature and coupling of epigenomic and structural analyses sheds light on the alterations that allow CRPC to circumvent hormonal therapy and may provide new drug targets for what is currently an incurable disease state.
2011-12-06 | GSE34174 | GEO
Project description:The androgen receptor (AR) is a ligand-inducible transcription factor that mediates androgen action in target tissues. Upon ligand binding, the AR binds to thousands of genomic loci and activates a cell-type specific gene program. Prostate cancer growth and progression depend on androgen-induced AR signalling. Treatment of advanced prostate cancer through medical or surgical castration leads to initial response and durable remission, but resistance inevitably develops. In castration-resistant prostate cancer (CRPC), AR activity remains critical for tumor growth despite androgen deprivation. While previous studies have focused on ligand-dependent AR signalling, in this study we explore AR function under the androgen-deprived conditions characteristic of CRPC. Our data demonstrate that the AR persistently occupies a distinct set of genomic loci after androgen deprivation in CRPC. These androgen-independent AR occupied regions have constitutively open chromatin structures that lack the canonical androgen response element and are independent of FoxA1, a transcription factor involved in ligand-dependent AR targeting. Many AR binding events occur at proximal promoters, which can act as enhancers to augment transcriptional activities of other promoters through DNA looping. We further show that androgen-independent AR binding directs a distinct gene expression program in CRPC, which is necessary for the growth of CRPC after androgen withdrawal.
2012-10-02 | GSE40050 | GEO