Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA225675 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Since its discovery, there has been one central issue of significant clinical relevance related to expression of the truncated androgen receptor splice variant-7 (AR-v7), which lacks the C-terminal ligand binding domain and thus acquires ligand-independent transcriptional activity in castration-resistant prostate cancer (CRPC). That question is whether AR-v7 is simply a marker of enhanced AR transcriptional activity characteristic of resistance to 2nd generation androgen receptor signaling inhibitors (ARSi) like Abiraterone and Enzalutamide, or whether it drives lethal resistance to ARSi. To address this question, the present study utilized 4 independently derived CRPC patient-derived xenografts in which the genetic and phenotypic changes could be followed before and after the development of ARSi resistance. This allowed evaluation of the correlation between acquired resistance to ARSi and changes in the expression levels of full length AR (AR-FL) vs. AR-v7 during this process. The combined results document that elevated expression of AR-FL alone is sufficient for Abiraterone- but not Enzalutamide-resistance. This is true even if AR-FL has a gain-of-function mutation. Furthermore, Enzalutamide-resistance is consistently correlated with the acquisition of AR-v7 expression. To directly test the requirement for AR-v7 expression in ARSi-refractory CRPC, CRISPR-Cas9 knockout of AR-FL and/or AR-v7 in LNCaP-95 cells was performed to evaluate in vitro and in vivo growth responses. These results document that AR-v7 drives Enzalutamide-resistance and focuses the critical need to develop therapeutic options to prevent and/or inhibit AR-v7 driven lethal progression of CRPC.
2020-10-11 | GSE149433 | GEO
Project description:LREX' are a LnCAP/AR subline with natural expresison of the glucocorticoid receptor. We used the model to compare the AR and GR cistromes in prostate tissue.
2013-12-27 | GSE51497 | GEO
Project description:Despite the clinical success of Androgen Receptor (AR)-targeted therapies, reactivation of AR signalling remains the main driver of castration-resistant prostate cancer (CRPC) progression. In this study, we performed a comprehensive unbiased characterisation of LNCaP cells chronically exposed to multiple AR inhibitors (ARI). Combined proteomics and metabolomics analyses implicated an acquired metabolic phenotype common in ARI-resistant cells and associated with perturbed glucose and lipid metabolism. To exploit this phenotype, we delineated a subset of proteins consistently associated with ARI resistance.
2020-05-26 | PXD016836 | Pride
Project description:LREX' are a LnCAP/AR subline with natural expresison of the glucocorticoid receptor. We used the model to compare the AR and GR cistromes in prostate tissue. We determined the GR cistrone in the presence of Dex (100nM) treatment and the AR cistrome in the presene of DHT (1nM) treatment.
2013-12-27 | E-GEOD-51497 | biostudies-arrayexpress
Project description:The treatment of advanced prostate cancer has been transformed by novel antiandrogen therapies such as enzalutamide. Using the LnCaP/AR xenograft model, we identified induction of glucocorticoid receptor (GR) expression as a common feature of drug resistant tumors. From a resistant xenograft tumor, we derived a GR expressing resistant subline called LREX' which maintains the resistant phenotype. mRNA expression was used to characterize resistant tissues. LnCaP/AR cells were injected into castrate mice and tumors were established. Mice were then treated with vehicle (Con), 4 days of anti-androgen (ARN-509 10mgkg), or were maintained on anti-androgen (10mg/kg ARN-509 or enzalutamide) until emergence of resistance. Resistant tissues continued to be exposed to anti-androgen through time of harvest. LREX' (LnCaP/AR Resistant to Enzalutamide Xenograft Derived) was derived from an enzalutamide resistant xenograft and was re-injected into castrate mice undergoing continual treatment with enzalutamide. The GR probe on the Illumina array failed to detect GR expression. Therefore, GR expression as determined by qPCR is annotated separately. Of the 10 control tissues, 8 were analyzed twice (technical duplicates annotated as A and B).
2013-12-27 | E-GEOD-51873 | biostudies-arrayexpress
Project description:DHT-AR, E2-AR and R5020-AR target gene profiles in LNCaP
| PRJNA253024 | ENA
Project description:The treatment of advanced prostate cancer has been transformed by novel antiandrogen therapies such as enzalutamide. Using the LnCaP/AR xenograft model, we identified induction of glucocorticoid receptor (GR) expression as a common feature of drug resistant tumors. From a resistant xenograft tumor, we derived a GR expressing resistant subline called LREX. In this model, activation of GR and AR activate a similar but distinguishable set of target genes.
2013-12-27 | GSE51871 | GEO
Project description:Next generation androgen receptor (AR) signaling inhibitors have significantly improved the survival of men with metastatic castration-resistant prostate cancer (mCPRC) but resistance remains a problem. Genomic alterations at the AR locus are present in ~50% of mCRPC patients, typically in association with large numbers of copy number gains and losses across the genome. To explore the functional consequences of these copy number alterations, we screened an shRNA library targeting all genes deleted in prostate cancer (the prostate cancer deletome: 4380 shRNAs targeting 730 genes) for next generation antiandrogen resistance using a clinically-validated model of enzalutamide-sensitive, AR-driven mCRPC LNCaP/AR. The Chromatin helicase DNA-binding factor (CHD1) scored as a top candidate and was validated in vitro and in vivo using multiple independent shRNAs and CRISPR guides. Mechanistically, CHD1 loss led to global changes in open and closed chromatin (ATAC-seq) as well as downregulation of canonical AR target genes upon the challenge of antiandrogen, despite robust AR expression. Integrative analysis of ATAC- and RNA-seq changes following CHD1 deletion identified 23 candidate transcription factor drivers of enzalutamide resistance. CRISPR-based unbiased functional screening identified 4 of these drivers may drive the AR-independent resistance, including glucocorticoid receptor (GR), BRN2, NR2F1 and TBX2. Genetic studies further establish that CHD1 loss confers antiandrogen resistance by converting mCRPC cells from AR-dependence to GR-dependence in one of the resistant LNCaP/AR clone. Thus, CHD1 functions as a molecular tuner to regulate chromatin plasticity and maintain oncogenic AR signaling, as well as AR dependency.
2020-03-26 | GSE127241 | GEO
Project description:Next generation androgen receptor (AR) signaling inhibitors have significantly improved the survival of men with metastatic castration-resistant prostate cancer (mCPRC) but resistance remains a problem. Genomic alterations at the AR locus are present in ~50% of mCRPC patients, typically in association with large numbers of copy number gains and losses across the genome. To explore the functional consequences of these copy number alterations, we screened an shRNA library targeting all genes deleted in prostate cancer (the prostate cancer deletome: 4380 shRNAs targeting 730 genes) for next generation antiandrogen resistance using a clinically-validated model of enzalutamide-sensitive, AR-driven mCRPC LNCaP/AR. The Chromatin helicase DNA-binding factor (CHD1) scored as a top candidate and was validated in vitro and in vivo using multiple independent shRNAs and CRISPR guides. Mechanistically, CHD1 loss led to global changes in open and closed chromatin (ATAC-seq) as well as downregulation of canonical AR target genes upon the challenge of antiandrogen, despite robust AR expression. Integrative analysis of ATAC- and RNA-seq changes following CHD1 deletion identified 23 candidate transcription factor drivers of enzalutamide resistance. CRISPR-based unbiased functional screening identified 4 of these drivers may drive the AR-independent resistance, including glucocorticoid receptor (GR), BRN2, NR2F1 and TBX2. Genetic studies further establish that CHD1 loss confers antiandrogen resistance by converting mCRPC cells from AR-dependence to GR-dependence in one of the resistant LNCaP/AR clone. Thus, CHD1 functions as a molecular tuner to regulate chromatin plasticity and maintain oncogenic AR signaling, as well as AR dependency.
2020-03-26 | GSE126917 | GEO
Project description:Next generation androgen receptor (AR) signaling inhibitors have significantly improved the survival of men with metastatic castration-resistant prostate cancer (mCPRC) but resistance remains a problem. Genomic alterations at the AR locus are present in ~50% of mCRPC patients, typically in association with large numbers of copy number gains and losses across the genome. To explore the functional consequences of these copy number alterations, we screened an shRNA library targeting all genes deleted in prostate cancer (the prostate cancer deletome: 4380 shRNAs targeting 730 genes) for next generation antiandrogen resistance using a clinically-validated model of enzalutamide-sensitive, AR-driven mCRPC LNCaP/AR. The Chromatin helicase DNA-binding factor (CHD1) scored as a top candidate and was validated in vitro and in vivo using multiple independent shRNAs and CRISPR guides. Mechanistically, CHD1 loss led to global changes in open and closed chromatin (ATAC-seq) as well as downregulation of canonical AR target genes upon the challenge of antiandrogen, despite robust AR expression. Integrative analysis of ATAC- and RNA-seq changes following CHD1 deletion identified 23 candidate transcription factor drivers of enzalutamide resistance. CRISPR-based unbiased functional screening identified 4 of these drivers may drive the AR-independent resistance, including glucocorticoid receptor (GR), BRN2, NR2F1 and TBX2. Genetic studies further establish that CHD1 loss confers antiandrogen resistance by converting mCRPC cells from AR-dependence to GR-dependence in one of the resistant LNCaP/AR clone. Thus, CHD1 functions as a molecular tuner to regulate chromatin plasticity and maintain oncogenic AR signaling, as well as AR dependency.
2020-03-26 | GSE127957 | GEO