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1.
Clin Cancer Res ; 25(22): 6764-6780, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31481513

RESUMEN

PURPOSE: Androgen receptor (AR)-targeting prostate cancer drugs, which are predominantly competitive ligand-binding domain (LBD)-binding antagonists, are inactivated by common resistance mechanisms. It is important to develop next-generation mechanistically distinct drugs to treat castration- and drug-resistant prostate cancers. EXPERIMENTAL DESIGN: Second-generation AR pan antagonist UT-34 was selected from a library of compounds and tested in competitive AR binding and transactivation assays. UT-34 was tested using biophysical methods for binding to the AR activation function-1 (AF-1) domain. Western blot, gene expression, and proliferation assays were performed in various AR-positive enzalutamide-sensitive and -resistant prostate cancer cell lines. Pharmacokinetic and xenograft studies were performed in immunocompromised rats and mice. RESULTS: UT-34 inhibits the wild-type and LBD-mutant ARs comparably and inhibits the in vitro proliferation and in vivo growth of enzalutamide-sensitive and -resistant prostate cancer xenografts. In preclinical models, UT-34 induced the regression of enzalutamide-resistant tumors at doses when the AR is degraded; but, at lower doses, when the AR is just antagonized, it inhibits, without shrinking, the tumors. This indicates that degradation might be a prerequisite for tumor regression. Mechanistically, UT-34 promotes a conformation that is distinct from the LBD-binding competitive antagonist enzalutamide and degrades the AR through the ubiquitin proteasome mechanism. UT-34 has a broad safety margin and exhibits no cross-reactivity with G-protein-coupled receptor kinase and nuclear receptor family members. CONCLUSIONS: Collectively, UT-34 exhibits the properties necessary for a next-generation prostate cancer drug.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Feniltiohidantoína/análogos & derivados , Neoplasias de la Próstata/metabolismo , Administración Oral , Antagonistas de Receptores Androgénicos/administración & dosificación , Antagonistas de Receptores Androgénicos/efectos adversos , Antagonistas de Receptores Androgénicos/farmacocinética , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Biomarcadores de Tumor , Línea Celular Tumoral , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos/genética , Expresión Génica , Humanos , Masculino , Ratones , Mutación , Feniltiohidantoína/administración & dosificación , Feniltiohidantoína/efectos adversos , Feniltiohidantoína/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica , Proteolisis , Ratas , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Transducción de Señal/efectos de los fármacos , Ubiquitina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Oncogene ; 38(7): 1136-1150, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30237440

RESUMEN

Elucidation of mechanisms underlying the increased androgen receptor (AR) activity and subsequent development of aggressive prostate cancer (PrCa) is pivotal in developing new therapies. Using a systems biology approach, we interrogated the AR-regulated proteome and identified PDZ binding kinase (PBK) as a novel AR-regulated protein that regulates full-length AR and AR variants (ARVs) activity in PrCa. PBK overexpression in aggressive PrCa is associated with early biochemical relapse and poor clinical outcome. In addition to its carboxy terminus ligand-binding domain, PBK directly interacts with the amino terminus transactivation domain of the AR to stabilise it thereby leading to increased AR protein expression observed in PrCa. Transcriptome sequencing revealed that PBK is a mediator of global AR signalling with key roles in regulating tumour invasion and metastasis. PBK inhibition decreased growth of PrCa cell lines and clinical specimen cultured ex vivo. We uncovered a novel interplay between AR and PBK that results in increased AR and ARVs expression that executes AR-mediated growth and progression of PrCa, with implications for the development of PBK inhibitors for the treatment of aggressive PrCa.


Asunto(s)
Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias de la Próstata/metabolismo , Receptores Androgénicos/metabolismo , Transducción de Señal , Línea Celular Tumoral , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Humanos , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Inhibidores de Proteínas Quinasas/farmacología , Receptores Androgénicos/genética
3.
J Med Chem ; 62(2): 491-511, 2019 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-30525603

RESUMEN

In our effort to find small-molecule treatments of advanced prostate cancers (PCs), a novel series of indolyl and indolinyl propanamides (series II and III) were discovered as selective androgen receptor degraders (SARDs). Initial studies of androgen receptor (AR) antagonist (1) and agonist (2) propanamides yielded a tertiary aniline (3) with novel SARD activity but poor metabolic stability. Cyclization to II and III produced submicromolar AR antagonism and protein degradation selective to AR and AR splice variant (AR SV). II and III maintained potency against enzalutamide-resistant (Enz-R) mutant ARs and PC cells and were efficacious in Enz-R xenografts, suggesting their potential to treat advanced PCs. Design, synthesis, and biological activity of novel SARDs that could potentially be used for the treatment of a wide spectrum of PCs including castration-resistant, Enz-R, and/or AR SV-dependent advanced PCs that are often untreatable with known hormone therapies are discussed.


Asunto(s)
Amidas/química , Diseño de Fármacos , Resistencia a Antineoplásicos , Receptores Androgénicos/metabolismo , Amidas/farmacología , Amidas/uso terapéutico , Antagonistas de Receptores Androgénicos/química , Andrógenos/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Indoles/química , Masculino , Ratones , Feniltiohidantoína/análogos & derivados , Feniltiohidantoína/farmacología , Feniltiohidantoína/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Proteolisis , Ratas , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Mol Cell Endocrinol ; 465: 27-35, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28789969

RESUMEN

The hormone testosterone plays crucial roles during male development and puberty and throughout life, as an anabolic regulator of muscle and bone structure and function. The actions of testosterone are mediated, primarily, through the androgen receptor, a member of the nuclear receptor superfamily. The androgen receptor gene is located on the X-chromosome and receptor levels are tightly controlled both at the level of transcription of the gene and post-translationally at the protein level. Sp1 has emerged as the major driver of expression of the androgen receptor gene, while auto-regulation by androgens is associated with both positive and negative regulation in a possible cell-selective manner. Research into the networks of positive and negative regulators of the androgen receptor gene are vital in order to understand the temporal and spatial control of receptor levels and the consequences for healthy aging and disease. A clear understanding of the multiple transcription factors participating in regulation of the androgen receptor gene will likely aid in the development and application of hormone therapies to boast or curb receptor activity.


Asunto(s)
Andrógenos/metabolismo , Especificidad de Órganos , Receptores Androgénicos/metabolismo , Envejecimiento/metabolismo , Animales , Transición Epitelial-Mesenquimal , Humanos
6.
Structure ; 26(1): 145-152.e3, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29225078

RESUMEN

The androgen receptor is a transcription factor that plays a key role in the development of prostate cancer, and its interactions with general transcription regulators are therefore of potential therapeutic interest. The mechanistic basis of these interactions is poorly understood due to the intrinsically disordered nature of the transactivation domain of the androgen receptor and the generally transient nature of the protein-protein interactions that trigger transcription. Here, we identify a motif of the transactivation domain that contributes to transcriptional activity by recruiting the C-terminal domain of subunit 1 of the general transcription regulator TFIIF. These findings provide molecular insights into the regulation of androgen receptor function and suggest strategies for treating castration-resistant prostate cancer.


Asunto(s)
ADN/química , Proteínas Intrínsecamente Desordenadas/química , Receptores Androgénicos/química , Factores de Transcripción TFII/química , Secuencias de Aminoácidos , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X , ADN/genética , ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Células HEK293 , Humanos , Proteínas Intrínsecamente Desordenadas/genética , Proteínas Intrínsecamente Desordenadas/metabolismo , Masculino , Modelos Moleculares , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Factores de Transcripción TFII/genética , Factores de Transcripción TFII/metabolismo , Activación Transcripcional
7.
Cancer Res ; 77(22): 6282-6298, 2017 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-28978635

RESUMEN

Androgen receptor (AR) mediates the growth of prostate cancer throughout its course of development, including in abnormal splice variants (AR-SV)-driven advanced stage castration-resistant disease. AR stabilization by androgens makes it distinct from other steroid receptors, which are typically ubiquitinated and degraded by proteasomes after ligand binding. Thus, targeting AR in advanced prostate cancer requires the development of agents that can sustainably degrade variant isoforms for effective therapy. Here we report the discovery and characterization of potent selective AR degraders (SARD) that markedly reduce the activity of wild-type and splice variant isoforms of AR at submicromolar doses. Three SARDs (UT-69, UT-155, and (R)-UT-155) bind the amino-terminal transcriptional activation domain AF-1, which has not been targeted for degradation previously, with two of these SARD (UT-69 and UT-155) also binding the carboxy-terminal ligand binding domain. Despite different mechanisms of action, all three SARDs degraded wild-type AR and inhibited AR function, exhibiting greater inhibitory potency than the approved AR antagonists. Collectively, our results introduce a new candidate class of next-generation therapeutics to manage advanced prostate cancer. Cancer Res; 77(22); 6282-98. ©2017 AACR.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Receptores Androgénicos/genética , Empalme Alternativo , Antagonistas de Receptores Androgénicos/química , Anilidas/química , Anilidas/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Perfilación de la Expresión Génica/métodos , Humanos , Indoles/química , Indoles/farmacología , Masculino , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Estructura Molecular , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Methods Mol Biol ; 1443: 3-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27246330

RESUMEN

The human genome codes for 48 members of the nuclear receptor superfamily, half of which have known ligands. Natural ligands for nuclear receptors are generally lipophilic in nature and include steroid hormones, bile acids, fatty acids, thyroid hormones, certain vitamins, and prostaglandins. Nuclear receptors regulate gene expression programs controlling development, differentiation, metabolic homeostasis and reproduction, in both a temporal and a tissue-selective manner. Since the original cloning of the cDNAs for the estrogen and glucocorticoid receptors, large strides have been made in our understanding of the structure and function of this family of transcription factors and their role in pathophysiology.


Asunto(s)
Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Receptores Citoplasmáticos y Nucleares/química , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas de Unión al ADN/genética , Humanos , Ligandos , Familia de Multigenes , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Receptores Citoplasmáticos y Nucleares/genética , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
9.
Methods Mol Biol ; 1443: 105-17, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27246336

RESUMEN

The detection of phosphorylation status of proteins has become a critical component of the analysis of activity, localization, and turnover studies of most proteins, particularly for those involved in signaling. The androgen receptor is no exception to this rule with its localization, transcriptional activity, and interactions determined by a series of key phosphorylations on serine residues. Here we have presented a series of techniques for the investigation of the phosphorylation status and intracellular localization of the androgen receptor after hormone and growth factor stimulation of cells in culture (in vitro) and in prostate cancer tissue (in vivo). Modified methods for immunohistochemistry, immunoblotting and immunofluorescence detection with high efficacy for the measurement and monitoring of androgen receptor are presented here alongside examples of their use.


Asunto(s)
Técnica del Anticuerpo Fluorescente/métodos , Immunoblotting/métodos , Técnicas para Inmunoenzimas/métodos , Neoplasias de la Próstata/metabolismo , Procesamiento Proteico-Postraduccional , Receptores Androgénicos/metabolismo , Análisis de Matrices Tisulares/métodos , Línea Celular Tumoral , Humanos , Inmunoprecipitación , Masculino , Fosforilación , Transducción de Señal
10.
ACS Chem Biol ; 11(9): 2499-505, 2016 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-27356095

RESUMEN

Castration-resistant prostate cancer is the lethal condition suffered by prostate cancer patients that become refractory to androgen deprivation therapy. EPI-001 is a recently identified compound active against this condition that modulates the activity of the androgen receptor, a nuclear receptor that is essential for disease progression. The mechanism by which this compound exerts its inhibitory activity is however not yet fully understood. Here we show, by using high resolution solution nuclear magnetic resonance spectroscopy, that EPI-001 selectively interacts with a partially folded region of the transactivation domain of the androgen receptor, known as transactivation unit 5, that is key for the ability of prostate cells to proliferate in the absence of androgens, a distinctive feature of castration-resistant prostate cancer. Our results can contribute to the development of more potent and less toxic novel androgen receptor antagonists for treating this disease.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Clorhidrinas/farmacología , Orquiectomía , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Compuestos de Bencidrilo/uso terapéutico , Clorhidrinas/uso terapéutico , Humanos , Masculino , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Activación Transcripcional
11.
Clin Cancer Res ; 22(17): 4466-77, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27140928

RESUMEN

PURPOSE: Persistent androgen receptor (AR) transcriptional activity is clinically evident in castration-resistant prostate cancer (CRPC). Therefore, AR remains as a viable therapeutic target for CRPC. All current hormonal therapies target the C-terminus ligand-binding domain (LBD) of AR. By using EPI to target AR activation function-1 (AF-1), in the N-terminal domain that is essential for AR transactivation, we evaluate the ability of EPI to overcome several clinically relevant AR-related mechanisms of resistance. EXPERIMENTAL DESIGN: To study the effect of EPI on AR transcriptional activity against overexpressed coactivators, such as SRC1-3 and p300, luciferase reporter assays were performed using LNCaP cells. AR-negative COS-1 cells were employed for reporter assays to examine whether the length of polyglutamine tract affects inhibition by EPI. The effect of EPI on constitutively active AR splice variants was studied in LNCaP95 cells, which express AR-V7 variant. To evaluate the effect of EPI on the proliferation of LNCaP95 cells, we performed in vitro BrdUrd incorporation assay and in vivo studies using xenografts in mice. RESULTS: EPI effectively overcame several molecular alterations underlying aberrant AR activity, including overexpressed coactivators, AR gain-of-function mutations, and constitutively active AR-V7. EPI inhibited AR transcriptional activity regardless of the length of polyglutamine tract. Importantly, EPI significantly inhibited the in vitro and in vivo proliferation of LNCaP95 prostate cancer cells, which are androgen independent and enzalutamide resistant. CONCLUSIONS: These findings support EPI as a promising therapeutic agent to treat CRPC, particularly against tumors driven by constitutively active AR splice variants that are resistant to LBD-targeting drugs. Clin Cancer Res; 22(17); 4466-77. ©2016 AACRSee related commentary by Sharp et al., p. 4280.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Compuestos de Bencidrilo/farmacología , Clorhidrinas/farmacología , Resistencia a Antineoplásicos , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Mutación , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Unión Proteica , Empalme del ARN , Receptores Androgénicos/genética , Transducción de Señal/efectos de los fármacos , Activación Transcripcional , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Asian J Androl ; 18(5): 687-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27212126

RESUMEN

The role of androgen receptor (AR) in the initiation and progression of prostate cancer (PCa) is well established. Competitive inhibition of the AR ligand-binding domain (LBD) has been the staple of antiandrogen therapies employed to combat the disease in recent years. However, their efficacy has often been limited by the emergence of resistance, mediated through point mutations, and receptor truncations. As a result, the prognosis for patients with malignant castrate resistant disease remains poor. The amino-terminal domain (NTD) of the AR has been shown to be critical for AR function. Its modular activation function (AF-1) is important for both gene regulation and participation in protein-protein interactions. However, due to the intrinsically disordered structure of the domain, its potential as a candidate for therapeutic intervention has been dismissed in the past. The recent emergence of the small molecule EPI-001 has provided evidence that AR-NTD can be targeted therapeutically, independent of the LBD. Targeting of AR-NTD has the potential to disrupt multiple intermolecular interactions between AR and its coregulatory binding partners, in addition to intramolecular cross-talk between the domains of the AR. Therapeutics targeting these protein-protein interactions or NTD directly should also have efficacy against emerging AR splice variants which may play a role in PCa progression. This review will discuss the role of intrinsic disorder in AR function and illustrate how emerging therapies might target NTD in PCa.


Asunto(s)
Antagonistas de Receptores Androgénicos/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Progresión de la Enfermedad , Humanos , Masculino , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Activación Transcripcional
13.
J Natl Cancer Inst ; 108(5)2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26657335

RESUMEN

BACKGROUND: The androgen receptor (AR) is a major drug target in prostate cancer (PCa). We profiled the AR-regulated kinome to identify clinically relevant and druggable effectors of AR signaling. METHODS: Using genome-wide approaches, we interrogated all AR regulated kinases. Among these, choline kinase alpha (CHKA) expression was evaluated in benign (n = 195), prostatic intraepithelial neoplasia (PIN) (n = 153) and prostate cancer (PCa) lesions (n = 359). We interrogated how CHKA regulates AR signaling using biochemical assays and investigated androgen regulation of CHKA expression in men with PCa, both untreated (n = 20) and treated with an androgen biosynthesis inhibitor degarelix (n = 27). We studied the effect of CHKA inhibition on the PCa transcriptome using RNA sequencing and tested the effect of CHKA inhibition on cell growth, clonogenic survival and invasion. Tumor xenografts (n = 6 per group) were generated in mice using genetically engineered prostate cancer cells with inducible CHKA knockdown. Data were analyzed with χ(2) tests, Cox regression analysis, and Kaplan-Meier methods. All statistical tests were two-sided. RESULTS: CHKA expression was shown to be androgen regulated in cell lines, xenografts, and human tissue (log fold change from 6.75 to 6.59, P = .002) and was positively associated with tumor stage. CHKA binds directly to the ligand-binding domain (LBD) of AR, enhancing its stability. As such, CHKA is the first kinase identified as an AR chaperone. Inhibition of CHKA repressed the AR transcriptional program including pathways enriched for regulation of protein folding, decreased AR protein levels, and inhibited the growth of PCa cell lines, human PCa explants, and tumor xenografts. CONCLUSIONS: CHKA can act as an AR chaperone, providing, to our knowledge, the first evidence for kinases as molecular chaperones, making CHKA both a marker of tumor progression and a potential therapeutic target for PCa.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Colina Quinasa/metabolismo , Chaperonas Moleculares , Terapia Molecular Dirigida/métodos , Prostatectomía , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/enzimología , Receptores Androgénicos/metabolismo , Transducción de Señal , Anciano , Animales , Colina Quinasa/antagonistas & inhibidores , Colina Quinasa/genética , Inhibidores Enzimáticos/farmacología , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Prostatectomía/métodos , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Análisis de Secuencia de ADN , Ensayos Antitumor por Modelo de Xenoinjerto
14.
PLoS One ; 10(10): e0139990, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26448047

RESUMEN

Androgen receptor (AR) mediated signalling is necessary for normal development of the prostate gland and also drives prostate cancer (PCa) cell growth and survival, with many studies showing a correlation between increased receptor levels and therapy resistance with progression to fatal castrate recurrent PCa (CRPC). Although it has been held for some time that the transcription factor Sp1 is the main stimulator of AR gene transcription, comprehensive knowledge of the regulation of the AR gene remains incomplete. Here we describe and characterise in detail two novel active regulatory elements in the 5'UTR of the human AR gene. Both of these elements contain overlapping binding sites for the positive transcription factor Sp1 and the repressor protein pur-α. Aberrant cell signalling is characteristic of PCa and the transcriptional activity of the AR promoter in PCa cells is dependent upon the relative amounts of the two transcription factors. Together with our corroboration of the dominant role of Sp1, the findings support the rationale of targeting this transcription factor to inhibit tumour progression. This should be of particular therapeutic relevance in CRPC where the levels of the repressor pur-α are reduced.


Asunto(s)
Neoplasias de la Próstata/genética , Receptores Androgénicos/genética , Factor de Transcripción Sp1/fisiología , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Línea Celular Tumoral , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Gorilla gorilla/genética , Humanos , Masculino , Datos de Secuencia Molecular , Mutación , Pan troglodytes/genética , Pongo/genética , Regiones Promotoras Genéticas , Neoplasias de la Próstata/metabolismo , Unión Proteica , Receptores Androgénicos/metabolismo , Homología de Secuencia de Ácido Nucleico
15.
Future Sci OA ; 1(2): FSO47, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28031874

RESUMEN

The androgen receptor (AR), a ligand activated transcription factor plays a number of roles in reproduction, homeostasis and pathogenesis of disease. It has two major polymorphic sequences; a polyglutamine and a polyglycine repeat that determine the length of the protein and influence receptor folding, structure and function. Here, we review the role the folding of the AR plays in the pathogenesis of spinal-bulbar muscular atrophy (SBMA), a neuromuscular degenerative disease arising from expansion of the polyglutamine repeat. We discuss current management for SBMA patients and how research on AR structure function may lead to future drug treatments.

16.
Sex Dev ; 8(6): 339-49, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25500996

RESUMEN

Androgen receptor (AR) mutations are associated with androgen insensitivity syndrome (AIS). Missense mutations identified in the AR-N-terminal domain (AR-NTD) are rare, and clinical phenotypes are typically mild. We investigated 7 missense mutations and 2 insertion/deletions located in the AR-NTD. This study aimed to elucidate the pathogenic role of AR-NTD mutants in AIS and to use this knowledge to further define AR-NTD function. AR-NTD mutations (Q120E, A159T, G216R, N235K, G248V, L272F, and P380R) were introduced into AR-expression plasmids. Stably expressing cell lines were established for del57L and ins58L. Transactivation was measured using luciferase reporter constructs under the control of GRE and Pem promoters. Intrinsic fluorescence spectroscopy and partial proteolysis studies were performed for mutations which showed reduced activities by using a purified AR-AF1 protein. Pem-luciferase reporter activation was reduced for A159T, N235K, and G248V but not the GRE-luciferase reporter. Protein structure analysis detected no significant change in the AR-AF1 region for these mutations. Reduced cellular expression and transactivation activity were observed for ins58L. The mutations Q120E, G216R, L272F, P380R, and del57L showed small or no detectable changes in function. Thus, clinical and experimental analyses have identified novel AR-signalling defects associated with mutations in the structurally disordered AR-NTD domain in patients with AIS.


Asunto(s)
Síndrome de Resistencia Androgénica/genética , Mutación/genética , Regiones Promotoras Genéticas , Receptores Androgénicos/química , Receptores Androgénicos/genética , Dihidrotestosterona/farmacología , Femenino , Genes Reporteros , Células HEK293 , Humanos , Masculino , Proteínas Mutantes/metabolismo , Fenotipo , Estructura Terciaria de Proteína , Proteolisis/efectos de los fármacos , Espectrometría de Fluorescencia , Activación Transcripcional/efectos de los fármacos , Activación Transcripcional/genética
17.
Psychoneuroendocrinology ; 47: 43-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25001955

RESUMEN

Expression or introduction of the neuropeptide substance-P (SP; encoded by the TAC1 gene in humans and Tac1 in rodents) in the amygdala induces anxiety related behaviour in rodents. In addition, pharmacological antagonism of the main receptor of SP in humans; NK1, is anxiolytic. In the current study, we show that the Tac1 locus is up-regulated in primary rat amygdala neurones in response to activation of the glucocorticoid receptor (GR); a classic component of the stress response. Using a combination of bioinformatics, electrophoretic mobility shift assays (EMSA) and reporter plasmid magnetofection into rat primary amygdala neurones we identified a highly conserved GR response sequence (2GR) in the human TAC1 promoter that binds GR in response to dexamethasone (Dex) or forskolin. We also identified a second GR binding site in the human promoter that was polymorphic and whose T-allele is only found in Japanese and Chinese populations. We present evidence that the T-allele of SNPGR increases the activity of the TAC1 promoter through de-sequestration or de-repression of 2GR. The identification of Dex/forskolin response elements in the TAC1 promoter in amygdala neurones suggests a possible link in the chain of molecular events connecting GR activation and anxiety. In addition, the discovery of a SNP which can alter this response may have implications for our understanding of the role of regulatory variation in susceptibility to stress in specific populations.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Neuronas/metabolismo , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Receptores de Glucocorticoides/fisiología , Sustancia P/genética , Amígdala del Cerebelo/citología , Amígdala del Cerebelo/efectos de los fármacos , Animales , Animales Recién Nacidos , Ansiedad/genética , Ansiedad/metabolismo , Secuencia de Bases , Células Cultivadas , Colforsina/farmacología , Dexametasona/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Datos de Secuencia Molecular , Neuronas/efectos de los fármacos , Cultivo Primario de Células , Regiones Promotoras Genéticas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/agonistas , Homología de Secuencia de Ácido Nucleico , Sustancia P/metabolismo
18.
Horm Cancer ; 5(5): 299-311, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24895212

RESUMEN

The androgen receptor (AR) is a widely expressed ligand-activated transcription factor which mediates androgen signalling by binding to androgen response elements (AREs) in normal tissue and prostate cancer (PCa). Within tumours, the amount of AR plays a crucial role in determining cell growth, resistance to therapy and progression to fatal castrate recurrent PCa in which prostate cells appear to become independent of androgenic steroids. Despite the pivotal role of the AR in male development and fertility and all stages of PCa development, the mechanisms governing AR expression remain poorly understood. In this work, we describe an active nonconsensus androgen response element (ARE) in the 5' UTR of the human AR gene. The ARE represses transcription upon binding of activated AR, and this downregulation is relieved by disruption of the regulatory element through mutation. Also, multiple species comparison of the genomic region reveals that this ARE is specific to primates, leading to the conclusion that care must be exercised when elucidating the operation of the human AR in PCa based upon rodent promoter studies.


Asunto(s)
Regiones no Traducidas 5' , Andrógenos/metabolismo , Regulación de la Expresión Génica , Receptores Androgénicos/genética , Elementos de Respuesta , Animales , Secuencia de Bases , Sitios de Unión , Expresión Génica , Genes Reporteros , Humanos , Datos de Secuencia Molecular , Motivos de Nucleótidos , Primates , Unión Proteica , Alineación de Secuencia , Activación Transcripcional
19.
J Clin Invest ; 123(7): 2948-60, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23722902

RESUMEN

Hormone therapies for advanced prostate cancer target the androgen receptor (AR) ligand-binding domain (LBD), but these ultimately fail and the disease progresses to lethal castration-resistant prostate cancer (CRPC). The mechanisms that drive CRPC are incompletely understood, but may involve constitutively active AR splice variants that lack the LBD. The AR N-terminal domain (NTD) is essential for AR activity, but targeting this domain with small-molecule inhibitors is complicated by its intrinsic disorder. Here we investigated EPI-001, a small-molecule antagonist of AR NTD that inhibits protein-protein interactions necessary for AR transcriptional activity. We found that EPI analogs covalently bound the NTD to block transcriptional activity of AR and its splice variants and reduced the growth of CRPC xenografts. These findings suggest that the development of small-molecule inhibitors that bind covalently to intrinsically disordered proteins is a promising strategy for development of specific and effective anticancer agents.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos Hormonales/farmacología , Compuestos de Bencidrilo/farmacología , Clorhidrinas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/química , Animales , Antineoplásicos Hormonales/química , Compuestos de Bencidrilo/química , Células COS , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Clorhidrinas/química , Química Clic , Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Humanos , Luciferasas/biosíntesis , Luciferasas/genética , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Orquiectomía , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica , Estructura Terciaria de Proteína , Receptores Androgénicos/química , Receptores Androgénicos/genética , Estereoisomerismo , Activación Transcripcional/efectos de los fármacos , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Future Med Chem ; 5(10): 1109-20, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23795968

RESUMEN

Androgenic steroids are important for male development in utero and secondary sexual characteristics at puberty. In addition, androgens play a role in non-reproductive tissues, such as bone and muscle in both sexes. The actions of the androgens testosterone and dihydrotestosterone are mediated by a single receptor protein, the androgen receptor. Over the last 60-70 years there has been considerable research interest in the development of inhibitors of androgen receptor for the management of diseases such as prostate cancer. However, more recently, there is also a growing appreciation of the need for selective androgen modulators that would demonstrate tissue-selective agonist or antagonist activity. The chemistry and biology of selective agonists, antagonists and selective androgen receptor modulators will be discussed in this review.


Asunto(s)
Receptores Androgénicos/metabolismo , Regulación Alostérica , Anabolizantes/química , Anabolizantes/metabolismo , Anabolizantes/uso terapéutico , Antagonistas de Receptores Androgénicos/química , Antagonistas de Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/uso terapéutico , Andrógenos/química , Andrógenos/metabolismo , Andrógenos/uso terapéutico , Femenino , Humanos , Masculino , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/prevención & control , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/prevención & control , Receptores Androgénicos/química
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