Gene Expression analysis of castration-resistant prostate cancer bone metastases
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE29650 | GEO | 2011/06/02
SECONDARY ACCESSION(S): PRJNA141237
REPOSITORIES: GEO
Similar Datasets
Project description:Analysis of bone metastases tissue from castration-resistant prostate cancer patients at the RNA level in relation to expression of constitutively active androgen receptor variants termed AR-V7 and AR-V567es. Total RNA obtained from frozen bone metastases samples were analyzed using a gene expression array and further to reveal differences in-between sample groups according to expression of AR-V7 and AR-V567es mRNA levels. Samples were defined to have high (AR-V high) or low (others) expression of those variants, respectively, for definition and more information please see Hörnberg et al PLoS One April 2011 Vol 6 Issue 4 , link and PMID below.
2011-06-02 | E-GEOD-29650 | biostudies-arrayexpress
Project description:Castration-resistant PCa (CRPC) remains androgen receptor (AR) dependent. There are multiple mechanisms for reactivation of AR including expression of the constitutively active AR splice variant, AR-V7 (AR3). Earlier studies suggest that though the variants regulate many of the same genes as AR, they also have unique targets. Another argument is that the variant is a “weak” AR without unique targets. We have used an LN95 cell line that endogenously expresses AR and a low level of AR-V7 to compare the activities of the isoforms and to determine whether there is differential regulation of target genes. The transcriptomes for AR and AR-V7 were identified using RNA-Seq.
2021-12-31 | GSE184676 | GEO
Project description:In castration-resistant prostate cancer (CRPC), clinical response to androgen receptor (AR) antagonists is limited mainly due to AR-variants expression and restored AR signaling. The metabolite spermine is most abundant in prostate and it decreases as prostate cancer progresses, but its functions remain poorly understood. Here, we show spermine inhibits full-length androgen receptor (AR-FL) and androgen receptor splice variant 7 (AR-V7) signaling and suppresses CRPC cell proliferation by directly binding and inhibiting protein arginine methyltransferase PRMT1. Spermine reduces H4R3me2a modification at the AR locus and suppresses AR binding as well as H3K27ac modification levels at AR target genes. Spermine supplementation restrains CRPC growth in vivo. PRMT1 inhibition also suppresses AR-FL and AR-V7 signaling and reduces CRPC growth. Collectively, we demonstrate spermine as an anticancer metabolite by inhibiting PRMT1 to transcriptionally inhibit AR-FL and AR-V7 signaling in CRPC, and we indicate spermine and PRMT1 inhibition as powerful strategies overcoming limitations of current AR-based therapies in CRPC.
2023-10-11 | MTBLS8034 | MetaboLights
Project description:Liquid biopsies have demonstrated that the constitutively active androgen receptor splice variant-7 (AR-V7) associates with reduced response and overall survival (OS) from endocrine therapies in castration resistant prostate cancer (CRPC). However, these studies provide little information pertaining to AR-V7 biology and expression in prostate cancer (PC) tissue. Following generation and validation of a novel AR-V7 antibody for immunohistochemistry (IHC); nuclear AR-V7 protein expression was determined for 358 primary prostate samples (358 patients) and 293 metastatic biopsies (194 patients). Associations with disease progression, nuclear AR full length (AR-FL) expression, response to abiraterone and/or enzalutamide, and gene signatures (from three independent cohorts) was determined.
2018-10-19 | GSE118435 | GEO
Project description:The constitutively active androgen receptor (AR) splice variant 7 (AR-V7) plays an important role in the progression of castration-resistant prostate cancer (CRPC). Although biomarker studies established the role of AR-V7 in resistance to AR-targeting therapies, how AR-V7 mediates genomic functions in CRPC remains largely unknown. Using a ChIP-exo approach, we show AR-V7 binds to distinct genomic regions and recognizes a full-length androgen-responsive element in CRPC cells and patient tissues. Remarkably, we find dramatic differences in AR-V7 cistromes across diverse CRPC cells and patient tissues, regulating different target gene sets involved in CRPC progression. Surprisingly, we discover that HoxB13 is universally required for and colocalizes with AR-V7 binding to open chromatin across CRPC genomes. HoxB13 pioneers AR-V7 binding through direct physical interaction, and collaborates with AR-V7 to up-regulate target oncogenes. Transcriptional coregulation by HoxB13 and AR-V7 was further supported by their coexpression in tumors and circulating tumor cells from CRPC patients. Importantly, HoxB13 silencing significantly decreases CRPC growth through inhibition of AR-V7 oncogenic function. These results identify HoxB13 as a pivotal upstream regulator of AR-V7-driven transcriptomes that are often cell context-dependent in CRPC, suggesting that HoxB13 may serve as a therapeutic target for AR-V7-driven prostate tumors.
2018-05-31 | GSE99378 | GEO
Project description:This study aimed at exploring how would the novel AR N-terminal inhibitor affect the androgen receptor (AR) transcriptome, especially a subset of genes that are uniquely upregulated by AR-V7 in castration resistant prostate cancer cells. We performed next-generation sequencing-based gene expression profiling (RNA-sequencing) on the castration-resistant prostate cancer celll line LNCaP-95. LNCaP-95 expresses high level of endogeneous AR-V7, and also acquired an adaptive shift towards AR-V7-mediated AR signaling activity. Beside regulating the transcription of a subset of canonical wildtype AR genes, AR-V7 also mediates a distinct transcriptional program that is independent of wildtype AR in LNCaP-95. In this experiment, LNCaP-95 cells were treated with vehicle control or the AR-N terminal inhibitor SC912. The subsequent AR transcriptomic change following compound treatment, especially the AR-V7 unique genes were assessed by RNA-seq.
2024-04-30 | GSE253122 | GEO
Project description:Background. Androgen receptor splice variant-7 (AR-V7) is a truncated form of the androgen receptor protein which lacks the ligand-binding domain, the target of enzalutamide and abiraterone, but remains constitutively active as a transcription factor. We hypothesized that detection of AR-V7 in circulating tumor cells (CTCs) from men with advanced prostate cancer would be associated with resistance to enzalutamide and abiraterone. Methods. We used quantitative reverse-transcription polymerase-chain-reaction (qRT-PCR) to interrogate CTCs for the presence or absence of AR-V7 from prospectively enrolled patients with metastatic castration-resistant prostate cancer initiating treatment with either enzalutamide or abiraterone. We examined associations between AR-V7 status and PSA response rates, PSA-progression-free-survival (PSA-PFS), clinical/radiographic-progression-free-survival (PFS), and overall survival (OS). Multivariable Cox regression analyses were performed to determine the independent effect of AR-V7 status on clinical outcomes. Results. Thirty-one enzalutamide-treated patients and thirty-one abiraterone-treated patients were enrolled, of which 38.7% and 19.4% had detectable AR-V7 from CTCs, respectively. Among men receiving enzalutamide, AR-V7–positive patients had inferior PSA response rates (0% vs 52.6%, P=0.004), PSA-PFS (median: 1.4 vs 6.0 months, P<0.001), PFS (median: 2.1 vs 6.1 months, P<0.001), and OS (median: 5.5 months vs not reached, P=0.002) compared to AR-V7–negative patients. Similarly, among men receiving abiraterone, AR-V7–positive patients had inferior PSA response rates (0% vs 68.0%, P=0.004), PSA-PFS (median: 1.3 months vs not reached, P<0.001), PFS (median: 2.3 months vs not reached, P<0.001), and OS (median: 10.6 months vs not reached, P=0.006). The negative prognostic impact of AR-V7 was maintained after adjusting for full-length-AR expression. Conclusions. Detection of AR-V7 in CTCs from patients with castration-resistant prostate cancer is associated with resistance to enzalutamide and abiraterone. A total of four metastatic castration-resistant prostate tumor samples from four patients were subjected to RNA-seq. Two samples were positive for androgen receptor splice variant 7 and the other two were negative for this variant.
2014-09-03 | E-GEOD-56701 | biostudies-arrayexpress
Project description:Molecular drivers underlying bone metastases in human cancer are not well understood, in part due to constraints in bone tissue sampling. Here, we undertook RNA sequencing of circulating tumor cells (CTCs) obtained from blood samples of women with metastatic estrogen receptor (ER)+ breast cancer, comparing cases with progression in bone versus visceral organs. Among the activated cellular pathways in CTCs from bone-predominant breast cancer is Androgen Receptor (AR) signaling. AR gene expression is evident, as is its constitutively active splicing variant AR-v7. AR expression within CTCs is correlated with the duration of treatment with aromatase inhibitors, suggesting that it may contribute to acquired resistance to anti-estrogen therapy. In an established breast cancer xenograft model, a bone-tropic derivative displays increased AR expression, whose genetic or pharmacologic suppression reduces metastases to bone but not to lungs. Together, these observations identify AR signaling in CTCs from women with bone-predominant ER+ breast cancer, and provide a rationale for testing androgen inhibitors in this subset of patients.
2018-02-19 | GSE86978 | GEO
Project description:In order to define the genes responsible for the growth and survival of a human castration-resistant prostate cancer cell line, a short term (doxycycline inducible) knockdown system was developed and utilized. Three independent 22Rv1 cell isolates were derived for each of the following doxycycline-inducible shRNAs (shGFP, shAR3, and shVav3) (AR3 = AR-V7). The cells were grown in androgen depleted conditions, plus or minus doxycycline, for three days. RNA from the 18 samples was then sent to the University of Miami Genetics Core for RNA Integrity Number (RIN) evaluation and microarray analysis. Genes differentially regulated by AR-V7 knock-down or VAV3 knock-down were explored as downstream targets of AR-V7 or VAV3, respectively.
2018-08-16 | GSE104572 | GEO
Project description:Androgen receptor (AR) is critical for the progression of prostate cancer to the castration resistant (CRPC) state. Despite initial response, AR antagonists are ineffective long term in stifling AR activity due to their inability to repress expression of the AR or its splice variant, AR-V7. Here, we report that ACK1 tyrosine kinase, frequently deregulated in CRPCs, phosphorylates histone H4 at tyrosine 88, upstream of the AR transcription start site. WDR5/MLL2 complex reads the H4Y88 marks and modifies H3 in trans to deposit the transcriptionally activating H3K4 trimethyl marks, promoting AR transcription. Reversal of the pY88-H4 epigenetic marks by ACK1 small molecule inhibitor, (R)-9bMS, sensitized naïve and enzalutamide-resistant cancer cells, repressed AR and AR-V7 levels to mitigate in vivo CRPC tumor growth. Thus, a feed-forward ACK1-H4-WDR5/MLL2-AR/AR-V7 epigenetic circuit drives CRPC and is necessary for maintenance of the malignant state.
2017-03-01 | GSE79689 | GEO