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1.
Circulation ; 149(3): 227-250, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-37961903

RESUMO

BACKGROUND: Cardiac metabolic dysfunction is a hallmark of heart failure (HF). Estrogen-related receptors ERRα and ERRγ are essential regulators of cardiac metabolism. Therefore, activation of ERR could be a potential therapeutic intervention for HF. However, in vivo studies demonstrating the potential usefulness of ERR agonist for HF treatment are lacking, because compounds with pharmacokinetics appropriate for in vivo use have not been available. METHODS: Using a structure-based design approach, we designed and synthesized 2 structurally distinct pan-ERR agonists, SLU-PP-332 and SLU-PP-915. We investigated the effect of ERR agonist on cardiac function in a pressure overload-induced HF model in vivo. We conducted comprehensive functional, multi-omics (RNA sequencing and metabolomics studies), and genetic dependency studies both in vivo and in vitro to dissect the molecular mechanism, ERR isoform dependency, and target specificity. RESULTS: Both SLU-PP-332 and SLU-PP-915 significantly improved ejection fraction, ameliorated fibrosis, and increased survival associated with pressure overload-induced HF without affecting cardiac hypertrophy. A broad spectrum of metabolic genes was transcriptionally activated by ERR agonists, particularly genes involved in fatty acid metabolism and mitochondrial function. Metabolomics analysis showed substantial normalization of metabolic profiles in fatty acid/lipid and tricarboxylic acid/oxidative phosphorylation metabolites in the mouse heart with 6-week pressure overload. ERR agonists increase mitochondria oxidative capacity and fatty acid use in vitro and in vivo. Using both in vitro and in vivo genetic dependency experiments, we show that ERRγ is the main mediator of ERR agonism-induced transcriptional regulation and cardioprotection and definitively demonstrated target specificity. ERR agonism also led to downregulation of cell cycle and development pathways, which was partially mediated by E2F1 in cardiomyocytes. CONCLUSIONS: ERR agonists maintain oxidative metabolism, which confers cardiac protection against pressure overload-induced HF in vivo. Our results provide direct pharmacologic evidence supporting the further development of ERR agonists as novel HF therapeutics.


Assuntos
Insuficiência Cardíaca , Camundongos , Animais , Cardiomegalia/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Ácidos Graxos/metabolismo
2.
Nat Commun ; 14(1): 7791, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057326

RESUMO

Oncogenic lesions in pancreatic ductal adenocarcinoma (PDAC) hijack the epigenetic machinery in stromal components to establish a desmoplastic and therapeutic resistant tumor microenvironment (TME). Here we identify Class I histone deacetylases (HDACs) as key epigenetic factors facilitating the induction of pro-desmoplastic and pro-tumorigenic transcriptional programs in pancreatic stromal fibroblasts. Mechanistically, HDAC-mediated changes in chromatin architecture enable the activation of pro-desmoplastic programs directed by serum response factor (SRF) and forkhead box M1 (FOXM1). HDACs also coordinate fibroblast pro-inflammatory programs inducing leukemia inhibitory factor (LIF) expression, supporting paracrine pro-tumorigenic crosstalk. HDAC depletion in cancer-associated fibroblasts (CAFs) and treatment with the HDAC inhibitor entinostat (Ent) in PDAC mouse models reduce stromal activation and curb tumor progression. Notably, HDAC inhibition (HDACi) enriches a lipogenic fibroblast subpopulation, a potential precursor for myofibroblasts in the PDAC stroma. Overall, our study reveals the stromal targeting potential of HDACi, highlighting the utility of this epigenetic modulating approach in PDAC therapeutics.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Pâncreas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Fibroblastos/metabolismo , Carcinogênese/patologia , Microambiente Tumoral
3.
Nat Commun ; 14(1): 5195, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673892

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy in need of new therapeutic options. Using unbiased analyses of super-enhancers (SEs) as sentinels of core genes involved in cell-specific function, here we uncover a druggable SE-mediated RNA-binding protein (RBP) cascade that supports PDAC growth through enhanced mRNA translation. This cascade is driven by a SE associated with the RBP heterogeneous nuclear ribonucleoprotein F, which stabilizes protein arginine methyltransferase 1 (PRMT1) to, in turn, control the translational mediator ubiquitin-associated protein 2-like. All three of these genes and the regulatory SE are essential for PDAC growth and coordinately regulated by the Myc oncogene. In line with this, modulation of the RBP network by PRMT1 inhibition reveals a unique vulnerability in Myc-high PDAC patient organoids and markedly reduces tumor growth in male mice. Our study highlights a functional link between epigenetic regulation and mRNA translation and identifies components that comprise unexpected therapeutic targets for PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Masculino , Animais , Camundongos , RNA , Epigênese Genética , Sequências Reguladoras de Ácido Nucleico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Metiltransferases , Proteínas de Ligação a RNA/genética
4.
bioRxiv ; 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37745372

RESUMO

Oncogenic lesions in pancreatic ductal adenocarcinoma (PDAC) hijack the epigenetic machinery in stromal components to establish a desmoplastic and therapeutic resistant tumor microenvironment (TME). Here we identify Class I histone deacetylases (HDACs) as key epigenetic factors facilitating the induction of pro-desmoplastic and pro-tumorigenic transcriptional programs in pancreatic stromal fibroblasts. Mechanistically, HDAC-mediated changes in chromatin architecture enable the activation of pro-desmoplastic programs directed by serum response factor (SRF) and forkhead box M1 (FOXM1). HDACs also coordinate fibroblast pro-inflammatory programs inducing leukemia inhibitory factor (LIF) expression, supporting paracrine pro-tumorigenic crosstalk. HDAC depletion in cancer-associated fibroblasts (CAFs) and treatment with the HDAC inhibitor entinostat (Ent) in PDAC mouse models reduce stromal activation and curb tumor progression. Notably, HDAC inhibition (HDACi) enriches a lipogenic fibroblast subpopulation, a potential precursor for myofibroblasts in the PDAC stroma. Overall, our study reveals the stromal targeting potential of HDACi, highlighting the utility of this epigenetic modulating approach in PDAC therapeutics.

5.
Cell Rep ; 42(8): 112997, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37611587

RESUMO

Colorectal cancer (CRC) is driven by genomic alterations in concert with dietary influences, with the gut microbiome implicated as an effector in disease development and progression. While meta-analyses have provided mechanistic insight into patients with CRC, study heterogeneity has limited causal associations. Using multi-omics studies on genetically controlled cohorts of mice, we identify diet as the major driver of microbial and metabolomic differences, with reductions in α diversity and widespread changes in cecal metabolites seen in high-fat diet (HFD)-fed mice. In addition, non-classic amino acid conjugation of the bile acid cholic acid (AA-CA) increased with HFD. We show that AA-CAs impact intestinal stem cell growth and demonstrate that Ileibacterium valens and Ruminococcus gnavus are able to synthesize these AA-CAs. This multi-omics dataset implicates diet-induced shifts in the microbiome and the metabolome in disease progression and has potential utility in future diagnostic and therapeutic developments.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Microbiota , Animais , Camundongos , Ácidos e Sais Biliares , Metaboloma
6.
Proc Natl Acad Sci U S A ; 120(21): e2217826120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37192160

RESUMO

Molecular classification of gastric cancer (GC) identified a subgroup of patients showing chemoresistance and poor prognosis, termed SEM (Stem-like/Epithelial-to-mesenchymal transition/Mesenchymal) type in this study. Here, we show that SEM-type GC exhibits a distinct metabolic profile characterized by high glutaminase (GLS) levels. Unexpectedly, SEM-type GC cells are resistant to glutaminolysis inhibition. We show that under glutamine starvation, SEM-type GC cells up-regulate the 3 phosphoglycerate dehydrogenase (PHGDH)-mediated mitochondrial folate cycle pathway to produce NADPH as a reactive oxygen species scavenger for survival. This metabolic plasticity is associated with globally open chromatin structure in SEM-type GC cells, with ATF4/CEBPB identified as transcriptional drivers of the PHGDH-driven salvage pathway. Single-nucleus transcriptome analysis of patient-derived SEM-type GC organoids revealed intratumoral heterogeneity, with stemness-high subpopulations displaying high GLS expression, a resistance to GLS inhibition, and ATF4/CEBPB activation. Notably, coinhibition of GLS and PHGDH successfully eliminated stemness-high cancer cells. Together, these results provide insight into the metabolic plasticity of aggressive GC cells and suggest a treatment strategy for chemoresistant GC patients.


Assuntos
Fosfoglicerato Desidrogenase , Neoplasias Gástricas , Humanos , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , Glutamina/metabolismo , Nutrientes
7.
ACS Chem Biol ; 18(4): 756-771, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-36988910

RESUMO

Repetitive physical exercise induces physiological adaptations in skeletal muscle that improves exercise performance and is effective for the prevention and treatment of several diseases. Genetic evidence indicates that the orphan nuclear receptors estrogen receptor-related receptors (ERRs) play an important role in skeletal muscle exercise capacity. Three ERR subtypes exist (ERRα, ß, and γ), and although ERRß/γ agonists have been designed, there have been significant difficulties in designing compounds with ERRα agonist activity. Additionally, there are limited synthetic agonists that can be used to target ERRs in vivo. Here, we report the identification of a synthetic ERR pan agonist, SLU-PP-332, that targets all three ERRs but has the highest potency for ERRα. Additionally, SLU-PP-332 has sufficient pharmacokinetic properties to be used as an in vivo chemical tool. SLU-PP-332 increases mitochondrial function and cellular respiration in a skeletal muscle cell line. When administered to mice, SLU-PP-332 increased the type IIa oxidative skeletal muscle fibers and enhanced exercise endurance. We also observed that SLU-PP-332 induced an ERRα-specific acute aerobic exercise genetic program, and the ERRα activation was critical for enhancing exercise endurance in mice. These data indicate the feasibility of targeting ERRα for the development of compounds that act as exercise mimetics that may be effective in the treatment of numerous metabolic disorders and to improve muscle function in the aging.


Assuntos
Estrogênios , Tolerância ao Exercício , Receptores de Estrogênio , Animais , Camundongos , Tolerância ao Exercício/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Estrogênios/química , Estrogênios/farmacologia , Receptor ERRalfa Relacionado ao Estrogênio
8.
Gastroenterology ; 163(1): 239-256, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35461826

RESUMO

BACKGROUND & AIMS: Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine pancreas disorders. However, the transcriptional mechanisms that regulate mitochondrial function to support acinar cell physiology are poorly understood. Here, we aim to elucidate the function of estrogen-related receptor γ (ERRγ) in pancreatic acinar cell mitochondrial homeostasis and energy production. METHODS: Two models of ERRγ inhibition, GSK5182-treated wild-type mice and ERRγ conditional knock-out (cKO) mice, were established to investigate ERRγ function in the exocrine pancreas. To identify the functional role of ERRγ in pancreatic acinar cells, we performed histologic and transcriptome analysis with the pancreas isolated from ERRγ cKO mice. To determine the relevance of these findings for human disease, we analyzed transcriptome data from multiple independent human cohorts and conducted genetic association studies for ESRRG variants in 2 distinct human pancreatitis cohorts. RESULTS: Blocking ERRγ function in mice by genetic deletion or inverse agonist treatment results in striking pancreatitis-like phenotypes accompanied by inflammation, fibrosis, and cell death. Mechanistically, loss of ERRγ in primary acini abrogates messenger RNA expression and protein levels of mitochondrial oxidative phosphorylation complex genes, resulting in defective acinar cell energetics. Mitochondrial dysfunction due to ERRγ deletion further triggers autophagy dysfunction, endoplasmic reticulum stress, and production of reactive oxygen species, ultimately leading to cell death. Interestingly, ERRγ-deficient acinar cells that escape cell death acquire ductal cell characteristics, indicating a role for ERRγ in acinar-to-ductal metaplasia. Consistent with our findings in ERRγ cKO mice, ERRγ expression was significantly reduced in patients with chronic pancreatitis compared with normal subjects. Furthermore, candidate locus region genetic association studies revealed multiple single nucleotide variants for ERRγ that are associated with chronic pancreatitis. CONCLUSIONS: Collectively, our findings highlight an essential role for ERRγ in maintaining the transcriptional program that supports acinar cell mitochondrial function and organellar homeostasis and provide a novel molecular link between ERRγ and exocrine pancreas disorders.


Assuntos
Pâncreas Exócrino , Pancreatite Crônica , Células Acinares/patologia , Animais , Estrogênios/metabolismo , Humanos , Camundongos , Camundongos Knockout , Pâncreas/patologia , Pâncreas Exócrino/metabolismo , Pancreatite Crônica/patologia
9.
Med ; 3(2): 119-136, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35425930

RESUMO

Background: Ketogenic diet is a potential means of augmenting cancer therapy. Here, we explore ketone body metabolism and its interplay with chemotherapy in pancreatic cancer. Methods: Metabolism and therapeutic responses of murine pancreatic cancer were studied using KPC primary tumors and tumor chunk allografts. Mice on standard high-carbohydrate diet or ketogenic diet were treated with cytotoxic chemotherapy (nab-paclitaxel, gemcitabine, cisplatin). Metabolic activity was monitored with metabolomics and isotope tracing, including 2H- and 13C-tracers, liquid chromatography-mass spectrometry, and imaging mass spectrometry. Findings: Ketone bodies are unidirectionally oxidized to make NADH. This stands in contrast to the carbohydrate-derived carboxylic acids lactate and pyruvate, which rapidly interconvert, buffering NADH/NAD. In murine pancreatic tumors, ketogenic diet decreases glucose's concentration and tricarboxylic acid cycle contribution, enhances 3-hydroxybutyrate's concentration and tricarboxylic acid contribution, and modestly elevates NADH, but does not impact tumor growth. In contrast, the combination of ketogenic diet and cytotoxic chemotherapy substantially raises tumor NADH and synergistically suppresses tumor growth, tripling the survival benefits of chemotherapy alone. Chemotherapy and ketogenic diet also synergize in immune-deficient mice, although long-term growth suppression was only observed in mice with an intact immune system. Conclusions: Ketogenic diet sensitizes murine pancreatic cancer tumors to cytotoxic chemotherapy. Based on these data, we have initiated a randomized clinical trial of chemotherapy with standard versus ketogenic diet for patients with metastatic pancreatic cancer (NCT04631445).


Assuntos
Dieta Cetogênica , Neoplasias Pancreáticas , Animais , Carboidratos , Dieta Cetogênica/métodos , Humanos , Camundongos , NAD , Neoplasias Pancreáticas/dietoterapia , Neoplasias Pancreáticas/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Pancreáticas
10.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34446564

RESUMO

In macrophages, homeostatic and immune signals induce distinct sets of transcriptional responses, defining cellular identity and functional states. The activity of lineage-specific and signal-induced transcription factors are regulated by chromatin accessibility and other epigenetic modulators. Glucocorticoids are potent antiinflammatory drugs; however, the mechanisms by which they selectively attenuate inflammatory genes are not yet understood. Acting through the glucocorticoid receptor (GR), glucocorticoids directly repress inflammatory responses at transcriptional and epigenetic levels in macrophages. A major unanswered question relates to the sequence of events that result in the formation of repressive regions. In this study, we identify bromodomain containing 9 (BRD9), a component of SWI/SNF chromatin remodeling complex, as a modulator of glucocorticoid responses in macrophages. Inhibition, degradation, or genetic depletion of BRD9 in bone marrow-derived macrophages significantly attenuated their responses to both liposaccharides and interferon inflammatory stimuli. Notably, BRD9-regulated genes extensively overlap with those regulated by the synthetic glucocorticoid dexamethasone. Pharmacologic inhibition of BRD9 potentiated the antiinflammatory responses of dexamethasone, while the genetic deletion of BRD9 in macrophages reduced high-fat diet-induced adipose inflammation. Mechanistically, BRD9 colocalized at a subset of GR genomic binding sites, and depletion of BRD9 enhanced GR occupancy primarily at inflammatory-related genes to potentiate GR-induced repression. Collectively, these findings establish BRD9 as a genomic antagonist of GR at inflammatory-related genes in macrophages, and reveal a potential for BRD9 inhibitors to increase the therapeutic efficacies of glucocorticoids.


Assuntos
Montagem e Desmontagem da Cromatina , Dexametasona/farmacologia , Regulação da Expressão Gênica , Macrófagos/imunologia , Receptores de Glucocorticoides/metabolismo , Fatores de Transcrição/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Domínios Proteicos , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/genética , Fatores de Transcrição/genética
11.
Nature ; 586(7830): 606-611, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32814902

RESUMO

Islets derived from stem cells hold promise as a therapy for insulin-dependent diabetes, but there remain challenges towards achieving this goal1-6. Here we generate human islet-like organoids (HILOs) from induced pluripotent stem cells and show that non-canonical WNT4 signalling drives the metabolic maturation necessary for robust ex vivo glucose-stimulated insulin secretion. These functionally mature HILOs contain endocrine-like cell types that, upon transplantation, rapidly re-establish glucose homeostasis in diabetic NOD/SCID mice. Overexpression of the immune checkpoint protein programmed death-ligand 1 (PD-L1) protected HILO xenografts such that they were able to restore glucose homeostasis in immune-competent diabetic mice for 50 days. Furthermore, ex vivo stimulation with interferon-γ induced endogenous PD-L1 expression and restricted T cell activation and graft rejection. The generation of glucose-responsive islet-like organoids that are able to avoid immune detection provides a promising alternative to cadaveric and device-dependent therapies in the treatment of diabetes.


Assuntos
Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Evasão da Resposta Imune , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/imunologia , Organoides/citologia , Organoides/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linhagem Celular , Epigênese Genética , Feminino , Glucose/metabolismo , Rejeição de Enxerto , Xenoenxertos , Homeostase , Humanos , Tolerância Imunológica , Secreção de Insulina , Transplante das Ilhotas Pancreáticas , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Organoides/transplante , Linfócitos T/citologia , Linfócitos T/imunologia , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt4/metabolismo , Proteína Wnt4/farmacologia
12.
Dev Cell ; 49(2): 279-292.e5, 2019 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-31014480

RESUMO

The correct assignment of cell fate within fields of multipotent progenitors is essential for accurate tissue diversification. The first lymphatic vessels arise from pre-existing veins after venous endothelial cells become specified as lymphatic progenitors. Prox1 specifies lymphatic fate and labels these progenitors; however, the mechanisms restricting Prox1 expression and limiting the progenitor pool remain unknown. We identified a zebrafish mutant that displayed premature, expanded, and prolonged lymphatic specification. The gene responsible encodes the regulator of alternative splicing, Nova2. In zebrafish and human endothelial cells, Nova2 selectively regulates pre-mRNA splicing for components of signaling pathways and phosphoproteins. Nova2-deficient endothelial cells display increased Mapk/Erk signaling, and Prox1 expression is dynamically controlled by Erk signaling. We identify a mechanism whereby Nova2-regulated splicing constrains Erk signaling, thus limiting lymphatic progenitor cell specification. This identifies the capacity of a factor that tunes mRNA splicing to control assignment of cell fate during vascular differentiation.


Assuntos
Vasos Linfáticos/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Processamento Alternativo , Animais , Diferenciação Celular , Linhagem da Célula , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Linfangiogênese , Vasos Linfáticos/citologia , Masculino , Antígeno Neuro-Oncológico Ventral , Proteínas Supressoras de Tumor/metabolismo , Veias/citologia , Veias/metabolismo , Peixe-Zebra
13.
Cell ; 176(5): 1098-1112.e18, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30794774

RESUMO

Increased levels of intestinal bile acids (BAs) are a risk factor for colorectal cancer (CRC). Here, we show that the convergence of dietary factors (high-fat diet) and dysregulated WNT signaling (APC mutation) alters BA profiles to drive malignant transformations in Lgr5-expressing (Lgr5+) cancer stem cells and promote an adenoma-to-adenocarcinoma progression. Mechanistically, we show that BAs that antagonize intestinal farnesoid X receptor (FXR) function, including tauro-ß-muricholic acid (T-ßMCA) and deoxycholic acid (DCA), induce proliferation and DNA damage in Lgr5+ cells. Conversely, selective activation of intestinal FXR can restrict abnormal Lgr5+ cell growth and curtail CRC progression. This unexpected role for FXR in coordinating intestinal self-renewal with BA levels implicates FXR as a potential therapeutic target for CRC.


Assuntos
Neoplasias Intestinais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Linhagem Celular , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Ácido Desoxicólico/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Intestinais/genética , Intestinos , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/fisiologia , Organoides/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Risco , Transdução de Sinais , Ácido Taurocólico/análogos & derivados , Ácido Taurocólico/metabolismo , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia
14.
EBioMedicine ; 16: 63-75, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28119061

RESUMO

While invasion and metastasis of tumour cells are the principle factor responsible for cancer related deaths, the mechanisms governing the process remain poorly defined. Moreover, phenotypic divergence of sub-populations of tumour cells is known to underpin alternative behaviors linked to tumour progression such as proliferation, survival and invasion. In the context of melanoma, heterogeneity between two transcription factors, BRN2 and MITF, has been associated with phenotypic switching between predominantly invasive and proliferative behaviors respectively. Epigenetic changes, in response to external cues, have been proposed to underpin this process, however the mechanism by which the phenotypic switch occurs is unclear. Here we report the identification of the NFIB transcription factor as a novel downstream effector of BRN2 function in melanoma cells linked to the migratory and invasive characteristics of these cells. Furthermore, the function of NFIB appears to drive an invasive phenotype through an epigenetic mechanism achieved via the upregulation of the polycomb group protein EZH2. A notable target of NFIB mediated up-regulation of EZH2 is decreased MITF expression, which further promotes a less proliferative, more invasive phenotype. Together our data reveal that NFIB has the ability to promote dynamic changes in the chromatin state of melanoma cells to facilitate migration, invasion and metastasis.


Assuntos
Movimento Celular/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteínas de Homeodomínio/genética , Melanoma/genética , Fator de Transcrição Associado à Microftalmia/genética , Fatores de Transcrição NFI/genética , Fatores do Domínio POU/genética , Animais , Western Blotting , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Melanoma/metabolismo , Melanoma/patologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fator de Transcrição Associado à Microftalmia/metabolismo , Microscopia de Fluorescência , Fatores de Transcrição NFI/metabolismo , Invasividade Neoplásica , Fatores do Domínio POU/metabolismo , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo
15.
Endocrinology ; 158(3): 431-447, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27983866

RESUMO

Breast cancer is a heterogeneous disease and its complexity has hindered the development of efficacious treatments targeting all breast cancer subtypes. Many studies have linked the diversity of breast carcinogenesis and metastasis to aberrant epigenetic signaling and control. Here, we focus on the current state of the discipline and review the major epigenetic enzymes controlling chromatin structure and function in the context of breast cancer, including (1) DNA methyltransferases, (2) lysine methyltransferases and demethylases, (3) protein arginine methyltransferases, and (4) histone acetyltransferases and deacetylases. Moreover, therapeutic drugs targeting these epigenetic enzymes are rapidly emerging and/or undergoing clinical trials. Therefore, we discuss the pharmacological manipulation of epigenetic enzymes for breast cancer treatment and present new clinical and survival outcome analysis on epigenetic factors that have evaded analysis to date. Understanding and pharmacologically exploiting epigenetic regulation in breast cancer promises to be an essential aspect of next-generation drug development and adjuvant therapies targeting advanced disease and treatment-resistant tumors.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Epigênese Genética , Animais , Carcinogênese , Metilases de Modificação do DNA/metabolismo , Feminino , Histona Desacetilases/metabolismo , Histona Desmetilases/metabolismo , Humanos , Lisina Acetiltransferases/metabolismo
16.
Mol Endocrinol ; 30(6): 660-76, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27144290

RESUMO

Skeletal muscle remodels metabolic capacity, contractile and exercise phenotype in response to physiological demands. This adaptive remodeling response to physical activity can ameliorate/prevent diseases associated with poor diet and lifestyle. Our previous work demonstrated that skeletal muscle-specific transgenic expression of the neuron-derived orphan nuclear receptor, Nor-1 drives muscle reprogramming, improves exercise endurance, and oxidative metabolism. The current manuscript investigates the association between exercise, Nor-1 expression and the role of Nor-1 in adaptive remodeling. We demonstrate that Nor-1 expression is induced by exercise and is dependent on calcium/calcineurin signaling (in vitro and in vivo). Analysis of fatigue-resistant transgenic mice that express Nor-1 in skeletal muscle revealed increased hypertrophy and vascularization of muscle tissue. Moreover, we demonstrate that transgenic Nor-1 expression is associated with increased intracellular recycling, ie, autophagy, involving 1) increased expression of light chain 3A or LC3A-II, autophagy protein 5, and autophagy protein 12 in quadriceps femoris muscle extracts from Tg-Nor-1 (relative to Wild-type (WT) littermates); 2) decreased p62 expression indicative of increased autophagolysosome assembly; and 3) decreased mammalian target of rapamycin complex 1 activity. Transfection of LC3A-GFP-RFP chimeric plasmid demonstrated that autophagolysosome formation was significantly increased by Nor-1 expression. Furthermore, we demonstrated a single bout of exercise induced LC3A-II expression in skeletal muscle from C57BL/6 WT mice. This study, when combined with our previous studies, demonstrates that Nor-1 expression drives multiple physiological changes/pathways that are critical to the beneficial responses of muscle to exercise and provides insights into potential pharmacological manipulation of muscle reprogramming for the treatment of lifestyle induced chronic diseases.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Condicionamento Físico Animal , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Calcineurina/metabolismo , Cálcio/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/genética , Hipertrofia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Biológicos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/parasitologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Esteroides/genética , Receptores dos Hormônios Tireóideos/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia
17.
EBioMedicine ; 6: 59-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27211549

RESUMO

We have previously reported that RORγ expression was decreased in ER-ve breast cancer, and increased expression improves clinical outcomes. However, the underlying RORγ dependent mechanisms that repress breast carcinogenesis have not been elucidated. Here we report that RORγ negatively regulates the oncogenic TGF-ß/EMT and mammary stem cell (MaSC) pathways, whereas RORγ positively regulates DNA-repair. We demonstrate that RORγ expression is: (i) decreased in basal-like subtype cancers, and (ii) inversely correlated with histological grade and drivers of carcinogenesis in breast cancer cohorts. Furthermore, integration of RNA-seq and ChIP-chip data reveals that RORγ regulates the expression of many genes involved in TGF-ß/EMT-signaling, DNA-repair and MaSC pathways (including the non-coding RNA, LINC00511). In accordance, pharmacological studies demonstrate that an RORγ agonist suppresses breast cancer cell viability, migration, the EMT transition (microsphere outgrowth) and mammosphere-growth. In contrast, RNA-seq demonstrates an RORγ inverse agonist induces TGF-ß/EMT-signaling. These findings suggest pharmacological modulation of RORγ activity may have utility in breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Reparo do DNA , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Fator de Crescimento Transformador beta/genética , Benzamidas/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Metástase Neoplásica , Piperazinas/farmacologia , Propanóis/farmacologia , Análise de Sequência de RNA , Transdução de Sinais
18.
PLoS One ; 11(1): e0147179, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26812621

RESUMO

Nuclear hormone receptors have important roles in the regulation of metabolic and inflammatory pathways. The retinoid-related orphan receptor alpha (Rorα)-deficient staggerer (sg/sg) mice display several phenotypes indicative of aberrant lipid metabolism, including dyslipidemia, and increased susceptibility to atherosclerosis. In this study we demonstrate that macrophages from sg/sg mice have increased ability to accumulate lipids and accordingly exhibit larger lipid droplets (LD). We have previously shown that BMMs from sg/sg mice have significantly decreased expression of cholesterol 25-hydroxylase (Ch25h) mRNA, the enzyme that produces the oxysterol, 25-hydroxycholesterol (25HC), and now confirm this at the protein level. 25HC functions as an inverse agonist for RORα. siRNA knockdown of Ch25h in macrophages up-regulates Vldlr mRNA expression and causes increased accumulation of LDs. Treatment with physiological concentrations of 25HC in sg/sg macrophages restored lipid accumulation back to normal levels. Thus, 25HC and RORα signify a new pathway involved in the regulation of lipid homeostasis in macrophages, potentially via increased uptake of lipid which is suggested by mRNA expression changes in Vldlr and other related genes.


Assuntos
Hidroxicolesteróis/metabolismo , Gotículas Lipídicas/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Cromatografia em Camada Fina , Agonismo Inverso de Drogas , Metabolismo dos Lipídeos , Lipídeos/análise , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/química , Interferência de RNA , RNA Mensageiro/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Esteroide Hidroxilases/antagonistas & inibidores , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Regulação para Cima
19.
Mol Endocrinol ; 28(7): 1166-85, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24911119

RESUMO

Protein arginine methyltransferases (PRMTs) methylate arginine residues on histones and target transcription factors that play critical roles in many cellular processes, including gene transcription, mRNA splicing, proliferation, and differentiation. Recent studies have linked PRMT-dependent epigenetic marks and modifications to carcinogenesis and metastasis in cancer. However, the role of PRMT2-dependent signaling in breast cancer remains obscure. We demonstrate PRMT2 mRNA expression was significantly decreased in breast cancer relative to normal breast. Gene expression profiling, Ingenuity and protein-protein interaction network analysis after PRMT2-short interfering RNA transfection into MCF-7 cells, revealed that PRMT2-dependent gene expression is involved in cell-cycle regulation and checkpoint control, chromosomal instability, DNA repair, and carcinogenesis. For example, PRMT2 depletion achieved the following: 1) increased p21 and decreased cyclinD1 expression in (several) breast cancer cell lines, 2) decreased cell migration, 3) induced an increase in nucleotide excision repair and homologous recombination DNA repair, and 4) increased the probability of distance metastasis free survival (DMFS). The expression of PRMT2 and retinoid-related orphan receptor-γ (RORγ) is inversely correlated in estrogen receptor-positive breast cancer and increased RORγ expression increases DMFS. Furthermore, we found decreased expression of the PRMT2-dependent signature is significantly associated with increased probability of DMFS. Finally, weighted gene coexpression network analysis demonstrated a significant correlation between PRMT2-dependent genes and cell-cycle checkpoint, kinetochore, and DNA repair circuits. Strikingly, these PRMT2-dependent circuits are correlated with pan-cancer metagene signatures associated with epithelial-mesenchymal transition and chromosomal instability. This study demonstrates the role and significant correlation between a histone methyltransferase (PRMT2)-dependent signature, RORγ, the cell-cycle regulation, DNA repair circuits, and breast cancer survival outcomes.


Assuntos
Neoplasias da Mama/mortalidade , Regulação Neoplásica da Expressão Gênica/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Proteína-Arginina N-Metiltransferases/genética , Neoplasias da Mama/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Instabilidade Cromossômica/genética , Ciclina D1/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Cinetocoros/metabolismo , Células MCF-7 , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/biossíntese , Mapas de Interação de Proteínas , Proteína-Arginina N-Metiltransferases/biossíntese , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Interferente Pequeno , Receptores de Estrogênio/metabolismo , Transdução de Sinais
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