Bruceantin targets HSP90 to overcome resistance to hormone therapy in castration-resistant prostate cancer
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE145790 | GEO | 2021/02/24
REPOSITORIES: GEO
Similar Datasets
Project description:Bruceantin targets HSP90 to overcome resistance to hormone therapy in castration-resistant prostate cancer
| PRJNA608261 | ENA
Project description:Anti-androgen therapies including the new androgen receptor (AR) antagonist MDV3100 are the first therapeutic approach in treating prostate cancer (PCa). However, tumors frequently become castration resistant through multiple mechanisms including alternative expression of AR splice variants. To identify new inhibitors which block both full-length AR (AR-FL) and constitutively-active truncated AR splice variants (AR-Vs), a library of natural compounds was screened for molecules that could inhibit AR-driven transcription in PCa cells expressing AR-FL or AR-Vs. We identified the small-molecule Ailanthone (AIL) as a potent inhibitor of both AR-FL and AR-Vs. AIL down-regulates both AR itself and its target genes in PCa cell lines as well as orthotopic animal tumors. Moreover，AIL directly binds to the co-chaperone protein p23 and prevents AR’s interaction with HSP90, which results in the disruption of the AR-chaperone complex followed by Ubiquitin/proteasome-mediated degradation of AR as well as other p23 clients including AKT and Cdk4. Meanwhile, overexpression of p23 dose-dependently rescued AIL-mediated cell proliferation inhibition, suggesting that p23 might be a critical target of AIL. Furthermore, treatment of MDV3100-resistant 22RV1 xenografts with AIL reduced tumor volume by 77.5% (2 mg/kg/day AIL, intraperitoneal) and 79.2% (5 mg/kg/day AIL, oral) compared with the control group. Finally, AIL possesses favorable drug-like properties such as good bioavailability (25.7% F), high solubility, lack of CYP inhibition, and low hepatotoxicity, although signs of gastrointestinal toxicity were observed at high doses. In conclusion, AIL overcomes MDV3100 resistance in castration resistant prostate cancer (CRPC) with excellent absorption, distribution, metabolism, excretion, and toxicity (ADME/Tox) properties, thus suggesting that AIL is a potential candidate for the clinical treatment of CRPC.
2016-11-30 | GSE85541 | GEO
Project description:Prostate cancer is the most common, lethal malignancy in men. Although androgen withdrawal therapies are used to treat advanced disease, progression to a castration-resistant, end-stage is the usual outcome. In this study, the tested hypothesis was that the androgen receptor remains essential for the growth and viability of castration-resistant disease. Knocking down the androgen receptor in well-established tumors grown in castrated mice caused growth arrest, decreased serum PSA, and frequently regression and total eradication of tumors. Growth control of castration-resistant tumors appeared to be linked to the extent of androgen receptor knockdown, which triggers upregulation of many genes involved in apoptosis, cell cycle arrest, and inhibition of tumorigenesis and protein synthesis. Our findings provide proof of principle that in vivo knockdown of the androgen receptor is a viable therapeutic strategy to control and possibly eradicate prostate cancers that have progressed to the lethal castration-resistant state.
2009-02-20 | GSE13332 | GEO
Project description:Prostate cancer is the most common, lethal malignancy in men. Although androgen withdrawal therapies are used to treat advanced disease, progression to a castration-resistant, end-stage is the usual outcome. In this study, the tested hypothesis was that the androgen receptor remains essential for the growth and viability of castration-resistant disease. Knocking down the androgen receptor in well-established tumors grown in castrated mice caused growth arrest, decreased serum PSA, and frequently regression and total eradication of tumors. Growth control of castration-resistant tumors appeared to be linked to the extent of androgen receptor knockdown, which triggers upregulation of many genes involved in apoptosis, cell cycle arrest, and inhibition of tumorigenesis and protein synthesis. Our findings provide proof of principle that in vivo knockdown of the androgen receptor is a viable therapeutic strategy to control and possibly eradicate prostate cancers that have progressed to the lethal castration-resistant state. C4-2 human prostate cancer cells stably expressing a tetracycline-inducible AR-targeted short hairpin RNA (shRNA) or scrambled shRNA were generated. These two cell lines were incubated in the absence of androgens with or without doxycycline hyclase (DOX). Comparison analysis of the gene expression profiles of C4-2 cells stably expressing AR shRNA + DOX and control cells (AR shRNA - DOX and scrambled shRNA ± DOX) was conducted to identify differentially regulated genes due to AR knockdown after normalization and data filtering. Genes were considered to be significantly different if the expression in the induced AR shRNA + DOX cells was at least 1.7-fold greater or 1.7-fold less than that seen in the control cells, with P< 0.05.
2010-06-23 | E-GEOD-13332 | biostudies-arrayexpress
Project description:Clinical resistance such as androgen receptor (AR) mutation, AR overexpression, and AR splice variants (ARVs) restrict the second-generation antiandrogens benefit in patients with castration-resistant prostate cancer (CRPC). Several strategies have been implemented to develop novel antiandrogens to circumvent the occurring resistance. In this study, based on rational drug design, we discovered and identified a bifunctional small molecule Z15 as a potent AR antagonist and AR selective degrader. Z15 could directly bind to the AR ligand-binding domain (LBD) and inhibited DHT-induced AR nuclear translocation. Furthermore, Z15 promoted AR degradation through the proteasome pathway. As a result, our in vitro and in vivo studies showed Z15 efficiently suppressed AR and AR mutant transcription activity, downregulated mRNA and protein levels of AR target genes, as well as overcame AR LBD mutations, AR amplification, and ARVs-induced resistance in CRPC. In conclusion, our data illustrate the synergistic importance of AR antagonism and degradation in advanced prostate cancer treatment.
2023-02-02 | PXD035721 | Pride
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:Rationale: Aberrant androgen receptor (AR) signaling via full-length AR (AR-FL) and constitutively active AR variant 7 (AR-V7) plays a key role in the development of castration-resistant prostate cancer (CRPC) and resistance to hormone therapies. Simultaneous targeting of AR-FL and AR-V7 may be a promising strategy to overcome resistance to hormone therapy. This study aimed to identify novel drug candidates co-targeting AR-FL and AR-V7 activities and elucidate their molecular mechanism of anti-CRPC activities. Methods: Using a CRPC cell-based reporter assay system, we screened a small library of antimalarial agents to explore the possibility of repositioning them for CRPC treatment and identified bruceantin (BCT) as a potent anti-CRPC drug candidate. A series of cell-based, molecular, biochemical, and in vivo approaches were performed to evaluate the therapeutic potential and molecular mechanism of BCT in CRPC. These approaches include reporter gene assays, cell proliferation, RNA-seq, qRT-PCR, mouse xenografts, co-immunoprecipitation, GST pull-down, immobilized BCT pull-down, molecular modeling, and bioinformatic analyses. Results: We identified BCT as a highly potent inhibitor co-targeting AR-FL and AR-V7 activity. BCT inhibits the transcriptional activity of AR-FL/AR-V7 and downregulates their target genes in CRPC cells. In addition, BCT efficiently suppresses tumor growth and metastasis of CRPC cells. Mechanistically, BCT disrupts the interaction of HSP90 with AR-FL/AR-V7 by directly binding to HSP90 and inhibits HSP90 chaperone function, leading to degradation of AR-FL/AR-V7 through the ubiquitin-proteasome system. Clinically, HSP90 expression is upregulated and correlated with AR/AR-V7 levels in CRPC. Conclusion: Our findings suggest that BCT could serve as a promising therapeutic candidate against CRPC and highlight the potential benefit of targeting AR-FL/AR-V7-HSP90 axis to overcome resistance caused by aberrant AR-FL/AR-V7 signaling.
| S-EPMC7738850 | biostudies-literature
Project description:Castration-resistant prostate cancer is a lethal disease. The cell type(s) that survive androgen-deprivation remain poorly described despite global efforts to understand the various mechanisms of therapy resistance. We recently identified in wild type mouse prostates a rare population of luminal progenitor cells that we called LSCmed according to their FACS profile (Lin?/Sca-1+/CD49fmed). Here we investigated the prevalence and castration resistance of LSCmed in various mouse models of prostate tumorigenesis. In intact mice, we show that LSCmed prevalence remains low (5-10% of epithelial cells) when prostatic androgen receptor signaling unaltered (malignant Hi-Myc mice) but significantly increases in models exhibiting reduced prostatic androgen receptor signaling, rising up to 30% in premalignant tumors (Pb-PRL mice) and to >80% in castration-resistant prostate tumors driven by Pten loss (Ptenpc-/- mice). LSCmed tolerance to androgen deprivation was demonstrated by their persistence (Ptenpc-/-) or further enrichment (Pb-PRL) 2-3 weeks after castration as evidenced by FACS analysis. Transcriptomic analysis revealed that LSCmed represent a unique cell entity as their gene-expression profile is different from luminal and basal/stem cells, but shares markers of each. Their intrinsic androgen signaling is markedly decreased, which explains why LSCmed tolerate androgen-deprivation. This also enlightens why Ptenpc-/- tumors are castration-resistant since LSCmed represent the most prevalent cell type in this model. We validated CK4 as a specific marker for LSCmed on sorted cells and prostate tissues by immunostaining, allowing for the detection of LSCmed in various mouse prostate specimens. In castrated Ptenpc-/- prostates, BrdU staining revealed massive proliferation of CK4+ cells, further demonstrating their key role in castration-resistant prostate cancer progression. In all, this study identifies LSCmed as a probable source of prostate cancer relapse after androgen deprivation and as a new therapeutic target for the prevention of castrate-resistant prostate cancer.
2017-08-15 | E-MTAB-4991 | biostudies-arrayexpress
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.
2011-06-02 | GSE29650 | GEO
Project description:Posttranslational modifications of histones such as methylation regulate chromatin structure and gene expression. Methylation of histone lysine residues is generally performed by SET domain methyltransferases. Here, we identify the heterodimeric C21orf127/TRMT112 complex as a specific histone methyltransferase. Assembly of the seven-b-strand protein C21orf127 (also named Hemk2, N6amt1 or PrmC) with TRMT112 is essential to form an active enzyme, hereafter named KMT9 that writes the histone mark H4K12me1 in vitro and in vivo. The H4K12me1 mark is enriched at promoters of KMT9 target genes and co-localises with the active histone mark H4K12ac. By controlling expression of genes involved in energy metabolism, KMT9 regulates oxidative phosphorylation in androgen receptor-dependent and -independent prostate tumour cells. Importantly, KMT9 depletion severely affects proliferation of castration and enzalutamide-resistant prostate cancer cells and xenograft tumours. Together, our data link the writing of the H4K12me1 histone mark by KMT9 with KMT9-dependent gene expression, which in consequence regulates energy metabolism and proliferation. KMT9 executes these functions independently of androgen receptor and androgen signalling thus, providing a promising paradigm for the treatment of castration resistant prostate cancer.
2019-03-11 | PXD008965 | Pride