GATA2 shRNA Expression in Castration Resistant Prostate Cancer Cell Lines
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Josep Domingo-Domenech
PROVIDER: E-GEOD-58966 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:The transcription factor GATA2 regulates chemotherapy resistance in prostate cancer. We report a novel GATA2 transcriptional program that has implications for chemotherapy resistance disease and aggressiveness in castration resistant prostate cancer.
2014-11-04 | GSE58966 | GEO
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:Resistance to androgen deprivation therapies and increased androgen receptor (AR) activity are major drivers of castration-resistant prostate cancer (CRPC). Prior work has focused on targeting AR directly; however, the identification and targeting of co-activators of AR signaling remains an underexplored area. Here we demonstrate that the MLL (mixed-lineage leukemia) complex, a well-known contributor in MLL-fusion-positive leukemia, acts as a co-activator of AR signaling. AR interacts with the MLL complex via its subunit, menin. Small molecule inhibition of the menin-MLL interaction blocks AR signaling and inhibits tumor growth in vivo. Furthermore, we find that menin is up-regulated in CRPC and high expression correlates with poor overall survival. Our study identifies the MLL complex as a co-activator of AR that can be targeted in advanced prostate cancer. ASH2L / Menin / MLL1 were knocked down using shRNA /siRNA in two prostate cancer cell lines, VCaP and LNCaP.
2015-03-02 | E-GEOD-60836 | 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.
2015-01-21 | GSE63539 | GEO
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: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:The integration of diverse ‘omic’ datasets will increase our understanding of the key signaling pathways that drive disease. Here, we used clinical tissue cohorts corresponding to lethal metastatic castration resistant prostate cancer (CRPC) obtained at rapid autopsy to integrate mutational, transcriptomic, and phosphoproteomic datasets for pathway analysis. Using Tied Diffusion through Interacting Events (TieDIE), we integrated differentially expressed transcriptional master regulators, functionally mutated genes, and differentially ‘activated’ kinases in CRPC tissues to synthesize a robust signaling network consisting of pathways with known and novel gene interactions. For 6 individual CRPC patients for which we had transcriptomic and phosphoproteomic data we observed distinct pathway activation states for each patient profile. In one patient, the activated pathways were strikingly similar to a prostate cancer cell line, 22Rv1, providing us with a good pre-clinical model to test targeted, combination therapies. In all, synthesis of multiple ‘omic’ datasets revealed a plethora of pathway information suitable for targeted therapies in lethal prostate cancer.
2016-08-19 | PXD002286 | Pride
Project description:Androgen receptor (AR) pathway inhibition remains the cornerstone for first- and second-line prostate cancer therapies. Although AR signaling inhibitors, such as enzalutamide and abiraterone extend survival in recurrent and castration-resistant prostate cancer (CRPC), durable and complete responses are rare. Resistance mechanisms employed by metastatic CRPC include amplification of AR and AR splice variants in AR-positive CRPC (ARPC) and conversion to AR-null phenotypes, such as double-negative prostate cancer (DNPC) and small cell or neuroendocrine prostate cancer (SCNPC). We have shown previously that DNPC can bypass AR-dependence through fibroblast growth factor (FGF) signaling. However, the role of the fibroblast growth factor receptor (FGFR) pathway in other molecular subtypes of CRPC has not been elucidated.
2023-09-19 | GSE228283 | GEO
Project description:Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) â?? the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. RNA-seq profiles of prostate cancer cell lines to understand gene expression associated with enzalutamide treatment
2016-06-10 | E-GEOD-69896 | biostudies-arrayexpress