RESUMO
Bariatric surgery is associated with improved outcomes for several cancers, including breast cancer (BC), although the mechanisms mediating this protection are unknown. We hypothesized that elevated bile acid pools detected after bariatric surgery may be factors that contribute to improved BC outcomes. Patients with greater expression of the bile acid receptor FXR displayed improved survival in specific aggressive BC subtypes. FXR is a nuclear hormone receptor activated by primary bile acids. Therefore, we posited that activating FXR using an established FDA-approved agonist would induce anticancer effects. Using in vivo and in vitro approaches, we determined the anti-tumor potential of bile acid receptor agonism. Indeed, FXR agonism by the bile acid mimetic known commercially as Ocaliva ("OCA"), or Obeticholic acid (INT-747), significantly reduced BC progression and overall tumor burden in a pre-clinical model. The transcriptomic analysis of tumors in mice subjected to OCA treatment revealed differential gene expression patterns compared to vehicle controls. Notably, there was a significant down-regulation of the oncogenic transcription factor MAX (MYC-associated factor X), which interacts with the oncogene MYC. Gene set enrichment analysis (GSEA) further demonstrated a statistically significant downregulation of the Hallmark MYC-related gene set (MYC Target V1) following OCA treatment. In human and murine BC analyses in vitro, agonism of FXR significantly and dose-dependently inhibited proliferation, migration, and viability. In contrast, the synthetic agonism of another common bile acid receptor, the G protein-coupled bile acid receptor TGR5 (GPBAR1) which is mainly activated by secondary bile acids, failed to significantly alter cancer cell dynamics. In conclusion, agonism of FXR by primary bile acid memetic OCA yields potent anti-tumor effects potentially through inhibition of proliferation and migration and reduced cell viability. These findings suggest that FXR is a tumor suppressor gene with a high potential for use in personalized therapeutic strategies for individuals with BC.
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Triple-negative breast cancer (TNBC) is an aggressive subtype with no targeted therapeutics. The luminal androgen receptor (LAR) subtype constitutes 15% of TNBC and is enriched for androgen receptor (AR) and AR target genes. Here, we show that a cohort of TNBC not only expresses AR at a much higher rate (â¼80%) but also expresses AR splice variants (AR-SVs) (â¼20%), further subclassifying LAR-TNBC. Higher AR and AR-SV expression and corresponding aggressive phenotypes are observed predominantly in specimens obtained from African American women. LAR TNBC specimens are enriched for interferon, Janus kinase (JAK)-signal activator and transducer (STAT), and androgen signaling pathways, which are exclusive to AR-expressing epithelial cancer cells. AR- and AR-SV-expressing TNBC cell proliferation and xenograft and patient-tumor explant growth are inhibited by AR N-terminal domain-binding selective AR degrader or by a JAK inhibitor. Biochemical analysis suggests that STAT1 is an AR coactivator. Collectively, our work identifies pharmacologically targetable TNBC subtypes and identifies growth-promoting interaction between AR and JAK-STAT signaling.
Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão GênicaRESUMO
Androgen receptor splice variants (AR-SVs) contribute to the aggressive growth of castration-resistant prostate cancer (CRPC). AR-SVs, including AR-V7, are expressed in ~30% of CRPC, but minimally in treatment-naïve primary prostate cancer (PCa). Compared to Caucasian American (CA) men, African American (AA) men are more likely to be diagnosed with aggressive/potentially lethal PCa and have shorter disease-free survival. Expression of a truncated AR in an aggressively growing patient-derived xenograft developed with a primary PCa specimen from an AA patient led us to hypothesize that the expression of AR-SVs could be an indicator of aggressive growth both in PCa progression and at the CRPC stage in AA men. Tissue microarrays (TMAs) were created from formalin-fixed paraffin-embedded (FFPE) prostatectomy tumor blocks from 118 AA and 115 CA treatment-naïve PCa patients. TMAs were stained with AR-V7-speicifc antibody and with antibodies binding to the N-terminus domain (NTD) and ligand-binding domain (LBD) of the AR. Since over 20 AR-SVs have been identified, and most AR-SVs do not as yet have a specific antibody, we considered a 2.0-fold or greater difference in the NTD vs. LBD staining as indication of potential AR-SV expression. Two AA, but no CA, patient tumors stained positively for AR-V7. AR staining with NTD and LBD antibodies was robust in most patients, with 21% of patients staining at least 2-fold more for NTD than LBD, indicating that AR-SVs other than AR-V7 are expressed in primary treatment-naïve PCa. About 24% of the patients were AR-negative, and race differences in AR expression were not statistically significant. These results indicate that AR-SVs are not restricted to CRPC, but also are expressed in primary PCa at higher rate than previously reported. Future investigation of the relative expression of NTD vs. LBD AR-SVs could guide the use of newly developed treatments targeting the NTD earlier in the treatment paradigm.
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A major challenge for new drug discovery in the area of androgen receptor (AR) antagonists lies in predicting the druggable properties that will enable small molecules to retain their potency and stability during further studies in vitro and in vivo. Indole (compound 8) is a first-in-class AR antagonist with very high potency (IC50 = 0.085 µM) but is metabolically unstable. During the metabolic studies described herein, we synthesized new small molecules that exhibit significantly improved stability while retaining potent antagonistic activity for an AR. This structure-activity relationship (SAR) study of more than 50 compounds classified with three classes (Class I, II, and III) and discovered two compounds (32c and 35i) that are potent AR antagonists (e.g., IC50 = 0.021 µM, T1/2 = 120 min for compound 35i). The new antagonists exhibited improved in vivo pharmacokinetics (PK) with high efficacy antiandrogen activity in Hershberger and antiandrogen Enz-Res tumor xenograft models that overexpress AR (LNCaP-AR).
Assuntos
Antagonistas de Receptores de Andrógenos , Neoplasias da Próstata , Masculino , Humanos , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Receptores Androgênicos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Antagonistas de Androgênios , Nitrilas/farmacologia , Linhagem Celular Tumoral , Proliferação de CélulasRESUMO
Androgen receptor (AR) and its splice variants (AR-SVs) promote prostate cancer (PCa) growth by orchestrating transcriptional reprogramming. Mechanisms by which the low complexity and intrinsically disordered primary transactivation domain (AF-1) of AR and AR-SVs regulate transcriptional programming in PCa remains poorly defined. Using omics, live and fixed fluorescent microscopy of cells, and purified AF-1 and AR-V7 recombinant proteins we show here that AF-1 and the AR-V7 splice variant form molecular condensates by liquid-liquid phase separation (LLPS) that exhibit disorder characteristics such as rapid intracellular mobility, coactivator interaction, and euchromatin induction. The LLPS and other disorder characteristics were reversed by a class of small-molecule-selective AR-irreversible covalent antagonists (SARICA) represented herein by UT-143 that covalently and selectively bind to C406 and C327 in the AF-1 region. Interfering with LLPS formation with UT-143 or mutagenesis resulted in chromatin condensation and dissociation of AR-V7 interactome, all culminating in a transcriptionally incompetent complex. Biochemical studies suggest that C327 and C406 in the AF-1 region are critical for condensate formation, AR-V7 function, and UT-143's irreversible AR inhibition. Therapeutically, UT-143 possesses drug-like pharmacokinetics and metabolism properties and inhibits PCa cell proliferation and tumor growth. Our work provides critical information suggesting that clinically important AR-V7 forms transcriptionally competent molecular condensates and covalently engaging C327 and C406 in AF-1, dissolves the condensates, and inhibits its function. The work also identifies a library of AF-1-binding AR and AR-SV-selective covalent inhibitors for the treatment of PCa.
Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Receptores Androgênicos/metabolismo , Cisteína , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Neoplasias de Próstata Resistentes à Castração/patologia , Linhagem Celular Tumoral , Isoformas de Proteínas/metabolismoRESUMO
A series of propanamide derivatives were designed, synthesized, and pharmacologically characterized as selective androgen receptor degraders (SARDs) and pan-antagonists that exert a broad-scope androgen receptor (AR) antagonism. Incorporating different basic heteromonocyclic B-ring structural elements in the common A-ring-linkage-B-ring nonsteroidal antiandrogen general pharmacophore contributed to a novel scaffold of small molecules with SARD and pan-antagonist activities even compared to our recently published AF-1 binding SARDs such as UT-69 (11), UT-155 (12), and UT-34 (13). Compound 26f exhibited inhibitory and degradation effects in vitro in a wide array of wtAR, point mutant, and truncation mutant-driven prostate cancers (PCs). Further, 26f inhibited tumor cell growth in a xenograft model composed of enzalutamide-resistant (EnzR) LNCaP cells. These results demonstrate an advancement toward the development of novel SARDs and pan-antagonists with efficacy against EnzR prostate cancers.
Assuntos
Amidas/farmacologia , Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Amidas/síntese química , Amidas/química , Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Masculino , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
Traditional endocrine therapy for prostate cancer (PCa) has been directed at suppression of the androgen receptor (AR) signaling axis since Huggins et al. discovered that diethylstilbestrol (DES; an estrogen) produced chemical castration and PCa tumor regression. Androgen deprivation therapy (ADT) still remains the first-line PCa therapy. Insufficiency of ADT over time leads to castration-resistant PCa (CRPC) in which the AR axis is still active, despite castrate levels of circulating androgens. Despite the approval and use of multiple generations of competitive AR antagonists (antiandrogens), antiandrogen resistance emerges rapidly in CRPC due to several mechanisms, mostly converging in the AR axis. Recent evidence from multiple groups have defined noncompetitive or noncanonical direct binding sites on AR that can be targeted to inhibit the AR axis. This review discusses new developments in the PCa treatment paradigm that includes the next-generation molecules to noncanonical sites, proteolysis targeting chimera (PROTAC), or noncanonical N-terminal domain (NTD)-binding of selective AR degraders (SARDs). A few lead compounds targeting each of these novel noncanonical sites or with SARD activity are discussed. Many of these ligands are still in preclinical development, and a few early clinical leads have emerged, but successful late-stage clinical data are still lacking. The breadth and diversity of targets provide hope that optimized noncanonical inhibitors and/or SARDs will be able to overcome antiandrogen-resistant CRPC.
Assuntos
Antagonistas de Receptores de Andrógenos/uso terapêutico , Terapia de Alvo Molecular , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Humanos , Masculino , Proteólise/efeitos dos fármacosRESUMO
OBJECTIVE: The objective of this study is to identify and validate novel therapeutic target(s) in ovarian cancer. BACKGROUND: Development of targeted therapeutics in ovarian cancer has been limited by molecular heterogeneity. Although gene expression datasets are available, most of them lack appropriate pair-matched controls to define the alterations that result in the transformation of normal ovarian cells to cancerous cells. METHODS: We used microarray to compare the gene expression of treatment-naïve ovarian cancer tissue samples to pair-matched normal adjacent ovarian tissue from 24 patients. Ingenuity Pathway Analysis (IPA) was used to identify target pathways for further analysis. Integrin-linked kinase (ILK) expression in SKOV3 and OV90 cells was determined using Western blot. ILK was knocked down using CRISPR/Cas9 constructs. Subcutaneous xenograft study to determine the effect of ILK knockdown on tumor growth was performed in NOD SCID gamma mice. RESULTS: Significant upregulation of the ILK pathway was identified in 22 of the 24 cancer specimens, identifying it as a potential player that could contribute to the transformation of normal ovarian cells to cancerous cells. Knockdown of ILK in SKOV3 cells resulted in decreased cell proliferation and tumor growth, and inhibition of downstream kinase, AKT (protein kinase B). These results were further validated using an ILK-1 chemical inhibitor, compound 22. CONCLUSION: Our initial findings validate ILK as a potential therapeutic target for molecular inhibition in ovarian cancer, which warrants further investigation.
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We report herein the design, synthesis, and pharmacological characterization of a library of novel aryl pyrazol-1-yl-propanamides as selective androgen receptor degraders (SARDs) and pan-antagonists that exert broad-scope AR antagonism. Pharmacological evaluation demonstrated that introducing a pyrazole moiety as the B-ring structural element in the common A-ring-linkage-B-ring nonsteroidal antiandrogens' general pharmacophore allowed the development of a new scaffold of small molecules with unique SARD and pan-antagonist activities even compared to our recently published AF-1 binding SARDs such as UT-155 (9) and UT-34 (10). Novel B-ring pyrazoles exhibited potent AR antagonist activities, including promising distribution, metabolism, and pharmacokinetic properties, and broad-spectrum AR antagonist properties, including potent in vivo antitumor activity. 26a was able to induce an 80% tumor growth inhibition of xenografts derived from the enzalutamide-resistant (Enz-R) VCaP cell line. These results represent an advancement toward the development of novel AR antagonists for the treatment of Enz-R prostate cancer.
Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pirazóis/química , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/metabolismo , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Benzamidas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Meia-Vida , Humanos , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptores Androgênicos/química , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Dysregulated Wnt/ß-catenin activation plays a critical role in cancer progression, metastasis, and drug resistance. Genotoxic agents such as radiation and chemotherapeutics have been shown to activate the Wnt/ß-catenin signaling although the underlying mechanism remains incompletely understood. Here, we show that genotoxic agent-activated Wnt/ß-catenin signaling is independent of the FZD/LRP heterodimeric receptors and Wnt ligands. OTULIN, a linear linkage-specific deubiquitinase, is essential for the DNA damage-induced ß-catenin activation. OTULIN inhibits linear ubiquitination of ß-catenin, which attenuates its Lys48-linked ubiquitination and proteasomal degradation upon DNA damage. The association with ß-catenin is enhanced by OTULIN Tyr56 phosphorylation, which depends on genotoxic stress-activated ABL1/c-Abl. Inhibiting OTULIN or Wnt/ß-catenin sensitizes triple-negative breast cancer xenograft tumors to chemotherapeutics and reduces metastasis. Increased OTULIN levels are associated with aggressive molecular subtypes and poor survival in breast cancer patients. Thus, OTULIN-mediated Wnt/ß-catenin activation upon genotoxic treatments promotes drug resistance and metastasis in breast cancers.
Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Endopeptidases/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Células HEK293 , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Biológicos , Metástase Neoplásica , Fosforilação , Fosfotirosina/metabolismo , Ubiquitinação , beta Catenina/metabolismoRESUMO
PURPOSE: Although important for apoptosis, the signaling pathway involving MOAP-1(Modulator of Apoptosis 1), RASSF1A (RAS association domain family 1A), and Bax (Bcl-2 associated X protein) is likely to be dysfunctional in many types of human cancers due to mechanisms associated with gene mutation and DNA hyper-methylation. The purpose of the present study was to assess the potential impact of generating physiologically relevant signaling pathway mediated by MOAP-1, Bax, and RASSF1A (MBR) in cancer cells and chemo-drug resistant cancer cells. METHODS: The tricistronic expression construct that encodes MOAP-1, Bax, and RASSF1A (MBR) or its mutant, MOAP-1∆BH3L, Bax and RASSF1A (MBRX) was expressed from an IRES (Internal Ribosome Entry Site)-based tricistronic expression vector in human breast cancer cells, including MCF-7, MCF-7-CR (cisplatin resistant) and triple negative breast cancer cells, BMET05, for functional characterization through in vitro and in vivo models. RESULTS: Transient expression of MBR potently promoted dose-dependent apoptotic signaling and chemo-sensitization in the cancer cells, as evidenced by loss of cell viability, nuclei condensation and Annexin-V positive staining while stable expression of MBR in MCF-7 cells significantly reduced the number of MBR stable clone by 86% and the stable clone exhibited robust chemo-drug sensitivity. In contrast, MBRX stable clone exhibited chemo-drug resistance while transiently over-expressed MOAP-1ΔBH3L inhibited the apoptotic activity of MBR. Moreover, the spheroids derived from the MBR stable clone displayed enhanced chemo-sensitivity and apoptotic activity. In mouse xenograft model, the tumors derived from MBR stable clone showed relatively high level of tumor growth retardation associated with the increase in apoptotic activity, leading to the decreases in both tumor weight and volume. CONCLUSIONS: Expression of MBR in cancer cells induces apoptotic cell death with enhanced chemo-sensitization requiring the BH3L domain of MOAP-1. In animal model, the expression of MBR significantly reduces the growth of tumors, suggesting that MBR is a potent apoptotic sensitizer with potential therapeutic benefits for cancer treatment.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Domínios e Motivos de Interação entre Proteínas , Proteínas Supressoras de Tumor/genética , Proteína X Associada a bcl-2/genética , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Modelos Animais de Doenças , Genes Reporter , Humanos , Camundongos , Modelos Biológicos , Ligação Proteica , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/metabolismoRESUMO
Sustained treatment of estrogen receptor (ER)-positive breast cancer with ER-targeting drugs results in ER mutations and refractory unresponsive cancers. Androgen receptor (AR), which is expressed in 80%-95% of ER-positive breast cancers, could serve as an alternate therapeutic target. Although AR agonists were used in the past to treat breast cancer, their use is currently infrequent due to virilizing side effects. Discovery of tissue-selective AR modulators (SARMs) has renewed interest in using AR agonists to treat breast cancer. Using translational models, we show that AR agonist and SARM, but not antagonist, inhibit the proliferation and growth of ER-positive breast cancer cells, patient-derived tissues, and patient-derived xenografts (PDX). Ligand-activated AR inhibits wild-type and mutant ER activity by reprogramming the ER and FOXA1 cistrome and rendering tumor growth inhibition. These findings suggest that ligand-activated AR may function as a non-canonical inhibitor of ER and that AR agonists may offer a safe and effective treatment for ER-positive breast cancer.
RESUMO
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.
Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/metabolismo , Administração Oral , Antagonistas de Receptores de Andrógenos/administração & dosagem , Antagonistas de Receptores de Andrógenos/efeitos adversos , Antagonistas de Receptores de Andrógenos/farmacocinética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Benzamidas , Biomarcadores Tumorais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Humanos , Masculino , Camundongos , Mutação , Nitrilas , Feniltioidantoína/administração & dosagem , Feniltioidantoína/efeitos adversos , Feniltioidantoína/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteólise , Ratos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ubiquitina/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Hormonal cancers affect over 400,000 men and women and contribute collectively to over 100,000 deaths in the United States alone. Thanks to advances in the understanding of these cancers at the molecular level and to the discovery of several disease-modifying therapeutics, the last decade has seen a plateauing or even a decreasing trend in the number of deaths from these cancers. These advanced therapeutics not only effectively slow the growth of hormonal cancers, but also provide an insight on how these cancers become refractory and evolve as an altogether distinct subset. This review summarizes the current therapeutic trends in hormonal cancers, with focus on prostate, breast and ovarian cancers. The review discusses the clinical drugs being used now, promising molecules that are going through various stages of development and makes some predictions on how the therapeutic landscape will shift in the next decade.
RESUMO
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.
Assuntos
Amidas/química , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos , Receptores Androgênicos/metabolismo , Amidas/farmacologia , Amidas/uso terapêutico , Antagonistas de Receptores de Andrógenos/química , Androgênios/química , Animais , Benzamidas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Indóis/química , Masculino , Camundongos , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Proteólise , Ratos , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
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.
Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores Androgênicos/genética , Processamento Alternativo , Antagonistas de Receptores de Andrógenos/química , Anilidas/química , Anilidas/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Perfilação da Expressão Gênica/métodos , Humanos , Indóis/química , Indóis/farmacologia , Masculino , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Estrutura Molecular , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Duchenne muscular dystrophy (DMD) is a neuromuscular disease that predominantly affects boys as a result of mutation(s) in the dystrophin gene. DMD is characterized by musculoskeletal and cardiopulmonary complications, resulting in shorter life-span. Boys afflicted by DMD typically exhibit symptoms within 3-5 years of age and declining physical functions before attaining puberty. We hypothesized that rapidly deteriorating health of pre-pubertal boys with DMD could be due to diminished anabolic actions of androgens in muscle, and that intervention with an androgen receptor (AR) agonist will reverse musculoskeletal complications and extend survival. While castration of dystrophin and utrophin double mutant (mdx-dm) mice to mimic pre-pubertal nadir androgen condition resulted in premature death, maintenance of androgen levels extended the survival. Non-steroidal selective-AR modulator, GTx-026, which selectively builds muscle and bone was tested in X-linked muscular dystrophy mice (mdx). GTx-026 significantly increased body weight, lean mass and grip strength by 60-80% over vehicle-treated mdx mice. While vehicle-treated castrated mdx mice exhibited cardiopulmonary impairment and fibrosis of heart and lungs, GTx-026 returned cardiopulmonary function and intensity of fibrosis to healthy control levels. GTx-026 elicits its musculoskeletal effects through pathways that are distinct from dystrophin-regulated pathways, making AR agonists ideal candidates for combination approaches. While castration of mdx-dm mice resulted in weaker muscle and shorter survival, GTx-026 treatment increased the muscle mass, function and survival, indicating that androgens are important for extended survival. These preclinical results support the importance of androgens and the need for intervention with AR agonists to treat DMD-affected boys.
Assuntos
Androgênios/metabolismo , Distrofia Muscular de Duchenne/genética , Androgênios/genética , Animais , Modelos Animais de Doenças , Distrofina/genética , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos mdx , Debilidade Muscular/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/genética , Distrofia Muscular de Duchenne/metabolismo , Receptores Androgênicos/metabolismo , Maturidade Sexual , Utrofina/genéticaRESUMO
Non-alcoholic steatohepatitis (NASH) affects 8-10 million people in the US and up to 75% of obese individuals. Despite this, there are no approved oral therapeutics to treat NASH and therefore the need for novel approaches exists. The estrogen receptor ß (ER-ß)-selective agonist, ß-LGND2, inhibits body weight and white adipose tissue, and increases metabolism, resulting in higher energy expenditure and thermogenesis. Due to favorable effects of ß-LGND2 on obesity, we hypothesized that ß-LGND2 will prevent NASH directly by reducing lipid accumulation in the liver or indirectly by favorably changing body composition. Male C57BL/6 mice fed with high fat diet (HFD) for 10 weeks or methionine choline-deficient diet for four weeks and treated with vehicle exhibited altered liver weights by twofold and increased serum transaminases by 2-6-folds. These changes were not observed in ß-LGND2-treated animals. Infiltration of inflammatory cells and collagen deposits, an indication of fibrosis, were observed in the liver of mice fed with HFD for 10 weeks, which were effectively blocked by ß-LGND2. Gene expression studies in the liver indicate that pregnane X receptor target genes were significantly increased by HFD, and the increase was inhibited by ß-LGND2. On the other hand, metabolomics indicate that bile acid metabolites were significantly increased by ß-LGND2. These studies demonstrate that an ER-ß agonist might provide therapeutic benefits in NASH by directly modulating the function of xenobiotic and bile acid receptors in the liver, which have important functions in the liver, and indirectly, as demonstrated before, by inhibiting adiposity. Impact statement Over 75-90% of those classified as clinically obese suffer from co-morbidities, the most common of which is non-alcoholic steatohepatitis (NASH). While there are currently no effective treatment approaches for NASH, data presented here provide preliminary evidence that an estrogen receptor ß-selective ligand could have the potential to reduce lipid accumulation and inflammation, and protect liver from NASH.
Assuntos
Ácidos e Sais Biliares/antagonistas & inibidores , Receptor beta de Estrogênio/agonistas , Isoquinolinas/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Animais , Deficiência de Colina/complicações , Dieta/efeitos adversos , Fígado/patologia , Masculino , Metabolômica , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologiaRESUMO
Most satiety-inducing obesity therapeutics, despite modest efficacy, have safety concerns that underscore the need for effective peripherally acting drugs. An attractive therapeutic approach for obesity is to optimize/maximize energy expenditure by increasing energy-utilizing thermogenic brown adipose tissue. We used in vivo and in vitro models to determine the role of estrogen receptor ß (ER-ß) and its ligands on adipose biology. RNA sequencing and metabolomics were used to determine the mechanism of action of ER-ß and its ligands. Estrogen receptor ß (ER-ß) and its selective ligand reprogrammed preadipocytes and precursor stem cells into brown adipose tissue and increased mitochondrial respiration. An ER-ß-selective ligand increased markers of tricarboxylic acid-dependent and -independent energy biogenesis and oxygen consumption in mice without a concomitant increase in physical activity or food consumption, all culminating in significantly reduced weight gain and adiposity. The antiobesity effects of ER-ß ligand were not observed in ER-ß-knockout mice. Serum metabolite profiles of adult lean and juvenile mice were comparable, while that of adult obese mice was distinct, indicating a possible impact of obesity on age-dependent metabolism. This phenotype was partially reversed by ER-ß-selective ligand. These data highlight a new role for ER-ß in adipose biology and its potential to be a safer alternative peripheral therapeutic target for obesity.-Ponnusamy, S., Tran, Q. T., Harvey, I., Smallwood, H. S., Thiyagarajan, T., Banerjee, S., Johnson, D. L., Dalton, J. T., Sullivan, R. D., Miller, D. D., Bridges, D., Narayanan, R. Pharmacologic activation of estrogen receptor ß increases mitochondrial function, energy expenditure, and brown adipose tissue.
Assuntos
Tecido Adiposo Marrom/metabolismo , Metabolismo Energético/fisiologia , Receptor beta de Estrogênio/agonistas , Receptor beta de Estrogênio/metabolismo , Isoquinolinas/farmacologia , Mitocôndrias/fisiologia , Tecido Adiposo Branco/fisiologia , Animais , Biomarcadores , Dieta Hiperlipídica , Receptor beta de Estrogênio/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Resistência à Insulina , Masculino , Camundongos , Camundongos Knockout , Obesidade/sangue , Obesidade/metabolismoRESUMO
Stress urinary incontinence (SUI), a prevalent condition, is represented by an involuntary leakage of urine that results, at least in part, from weakened or damaged pelvic floor muscles and is triggered by physical stress. Current treatment options are limited with no oral therapies available. The pelvic floor is rich in androgen receptor and molecules with anabolic activity including selective androgen receptor modulators (SARMs) may serve as therapeutic options for individuals with SUI. In this study, two SARMs (GTx-024 and GTx-027) were evaluated in a post-menopausal animal model in order to determine their effect on pelvic floor muscles. Female C57BL/6 mice were ovariectomized and their pelvic muscles allowed to regress. The animals were then treated with vehicle or doses of GTx-024 or GTx-027. Animal total body weight, lean body mass, and pelvic floor muscle weights were measured along with the expression of genes associated with muscle catabolism. Treatment with the SARMs resulted in a restoration of the pelvic muscles to the sham-operated weight. Coordinately, the induction of genes associated with muscle catabolism was inhibited. Although a trend was observed towards an increase in total lean body mass in the SARM-treated groups, no significant differences were detected. Treatment of an ovariectomized mouse model with SARMs resulted in an increase in pelvic floor muscles, which may translate to an improvement of symptoms associated with SUI and serves as the basis for evaluating their clinical use. J. Cell. Biochem. 118: 640-646, 2017. © 2016 Wiley Periodicals, Inc.