RESUMEN
The coordination of cellular biological processes is regulated in part via metabolic enzymes acting to match cellular metabolism to current conditions. The acetate activating enzyme, acyl-coenzyme A synthetase short-chain family member 2 (Acss2), has long been considered to have a predominantly lipogenic function. More recent evidence suggests that this enzyme has regulatory functions in addition to its role in providing acetyl-CoA for lipid synthesis. We used Acss2 knockout mice (Acss2-/-) to further investigate the roles this enzyme plays in three physiologically distinct organ systems that make extensive use of lipid synthesis and storage, including the liver, brain, and adipose tissue. We examined the resulting transcriptomic changes resulting from Acss2 deletion and assessed these changes in relation to fatty acid constitution. We find that loss of Acss2 leads to dysregulation of numerous canonical signaling pathways, upstream transcriptional regulatory molecules, cellular processes, and biological functions, which were distinct in the liver, brain, and mesenteric adipose tissues. The detected organ-specific transcriptional regulatory patterns reflect the complementary functional roles of these organ systems within the context of systemic physiology. While alterations in transcriptional states were evident, the loss of Acss2 resulted in few changes in fatty acid constitution in all three organ systems. Overall, we demonstrate that Acss2 loss institutes organ-specific transcriptional regulatory patterns reflecting the complementary functional roles of these organ systems. Collectively, these findings provide further confirmation that Acss2 regulates key transcription factors and pathways under well-fed, non-stressed conditions and acts as a transcriptional regulatory enzyme.
Asunto(s)
Acetato CoA Ligasa , Regulación de la Expresión Génica , Animales , Ratones , Acetato CoA Ligasa/genética , Acetato CoA Ligasa/metabolismo , Acetatos/metabolismo , Ácidos Grasos/metabolismo , Lipogénesis , Hígado/metabolismoRESUMEN
Hepatocellular carcinoma (HCC) is a leading cause of death among cirrhotic patients, for which chemopreventive strategies are lacking. Recently, we developed a simple human cell-based system modeling a clinical prognostic liver signature (PLS) predicting liver disease progression and HCC risk. In a previous study, we applied our cell-based system for drug discovery and identified captopril, an approved angiotensin converting enzyme (ACE) inhibitor, as a candidate compound for HCC chemoprevention. Here, we explored ACE as a therapeutic target for HCC chemoprevention. Captopril reduced liver fibrosis and effectively prevented liver disease progression toward HCC development in a diethylnitrosamine (DEN) rat cirrhosis model and a diet-based rat model for nonalcoholic steatohepatitis-induced (NASH-induced) hepatocarcinogenesis. RNA-Seq analysis of cirrhotic rat liver tissues uncovered that captopril suppressed the expression of pathways mediating fibrogenesis, inflammation, and carcinogenesis, including epidermal growth factor receptor (EGFR) signaling. Mechanistic data in liver disease models uncovered a cross-activation of the EGFR pathway by angiotensin. Corroborating the clinical translatability of the approach, captopril significantly reversed the HCC high-risk status of the PLS in liver tissues of patients with advanced fibrosis. Captopril effectively prevents fibrotic liver disease progression toward HCC development in preclinical models and is a generic and safe candidate drug for HCC chemoprevention.
Asunto(s)
Captopril , Carcinoma Hepatocelular , Neoplasias Hepáticas , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Captopril/farmacología , Captopril/uso terapéutico , Carcinogénesis , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/prevención & control , Quimioprevención , Progresión de la Enfermedad , Receptores ErbB/metabolismo , Cirrosis Hepática/prevención & control , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/prevención & control , Peptidil-Dipeptidasa A/metabolismo , Ratas , Activación TranscripcionalRESUMEN
Hepatic stellate cells (HSCs) drive hepatic fibrosis. Therapies that inactivate HSCs have clinical potential as antifibrotic agents. We previously identified acid ceramidase (aCDase) as an antifibrotic target. We showed that tricyclic antidepressants (TCAs) reduce hepatic fibrosis by inhibiting aCDase and increasing the bioactive sphingolipid ceramide. We now demonstrate that targeting aCDase inhibits YAP/TAZ activity by potentiating its phosphorylation-mediated proteasomal degradation via the ubiquitin ligase adaptor protein ß-TrCP. In mouse models of fibrosis, pharmacologic inhibition of aCDase or genetic knockout of aCDase in HSCs reduces fibrosis, stromal stiffness, and YAP/TAZ activity. In patients with advanced fibrosis, aCDase expression in HSCs is increased. Consistently, a signature of the genes most down-regulated by ceramide identifies patients with advanced fibrosis who could benefit from aCDase targeting. The findings implicate ceramide as a critical regulator of YAP/TAZ signaling and HSC activation and highlight aCDase as a therapeutic target for the treatment of fibrosis.
Asunto(s)
Ceramidasa Ácida , Células Estrelladas Hepáticas , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Fibrosis , Células Estrelladas Hepáticas/metabolismo , Humanos , Ratones , Transducción de SeñalRESUMEN
PURPOSE: To evaluate the prognostic value of posttreatment fibrosis in human PDAC patients, and to compare a type I collagen targeted MRI probe, CM-101, to the standard contrast agent, Gd-DOTA, for their abilities to identify FOLFIRINOX-induced fibrosis in a murine model of PDAC. EXPERIMENTAL DESIGN: Ninety-three chemoradiation-treated human PDAC samples were stained for fibrosis and outcomes evaluated. For imaging, C57BL/6 and FVB mice were orthotopically implanted with PDAC cells and FOLFIRINOX was administered. Mice were imaged with Gd-DOTA and CM-101. RESULTS: In humans, post-chemoradiation PDAC tumor fibrosis was associated with longer overall survival (OS) and disease-free survival (DFS) on multivariable analysis (OS P = 0.028, DFS P = 0.047). CPA increased the prognostic accuracy of a multivariable logistic regression model comprised of previously established PDAC risk factors [AUC CPA (-) = 0.76, AUC CPA (+) = 0.82]. In multiple murine orthotopic PDAC models, FOLFIRINOX therapy reduced tumor weight (P < 0.05) and increased tumor fibrosis by collagen staining (P < 0.05). CM-101 MR signal was significantly increased in fibrotic tumor regions. CM-101 signal retention was also increased in the more fibrotic FOLFIRINOX-treated tumors compared with untreated controls (P = 0.027), consistent with selective probe binding to collagen. No treatment-related differences were observed with Gd-DOTA imaging. CONCLUSIONS: In humans, post-chemoradiation tumor fibrosis is associated with OS and DFS. In mice, our MR findings indicate that translation of collagen molecular MRI with CM-101 to humans might provide a novel imaging technique to monitor fibrotic response to therapy to assist with prognostication and disease management.
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Carcinoma Ductal Pancreático/terapia , Quimioradioterapia Adyuvante , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/epidemiología , Páncreas/patología , Neoplasias Pancreáticas/terapia , Anciano , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Colágeno/análisis , Colágeno/metabolismo , Supervivencia sin Enfermedad , Femenino , Fibrosis , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Compuestos Heterocíclicos/administración & dosificación , Humanos , Irinotecán/administración & dosificación , Leucovorina/administración & dosificación , Imagen por Resonancia Magnética/métodos , Masculino , Ratones , Persona de Mediana Edad , Imagen Molecular/métodos , Sondas Moleculares/administración & dosificación , Recurrencia Local de Neoplasia/prevención & control , Compuestos Organometálicos/administración & dosificación , Oxaliplatino/administración & dosificación , Páncreas/diagnóstico por imagen , Páncreas/cirugía , Pancreatectomía , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is a chronic liver disease characterized by hepatic lipid accumulation, inflammation, and progressive fibrosis. Acetyl-CoA carboxylase (ACC) catalyzes the rate-limiting step of de novo lipogenesis and regulates fatty acid ß-oxidation in hepatocytes. ACC inhibition reduces hepatic fat content and markers of liver injury in patients with NASH; however, the effect of ACC inhibition on liver fibrosis has not been reported. METHODS: A direct role for ACC in fibrosis was evaluated by measuring de novo lipogenesis, procollagen production, gene expression, glycolysis, and mitochondrial respiration in hepatic stellate cells (HSCs) in the absence or presence of small molecule inhibitors of ACC. ACC inhibitors were evaluated in rodent models of liver fibrosis induced by diet or the hepatotoxin, diethylnitrosamine. Fibrosis and hepatic steatosis were evaluated by histological and biochemical assessments. RESULTS: Inhibition of ACC reduced the activation of TGF-ß-stimulated HSCs, as measured by both α-SMA expression and collagen production. ACC inhibition prevented a metabolic switch necessary for induction of glycolysis and oxidative phosphorylation during HSC activation. While the molecular mechanism by which inhibition of de novo lipogenesis blocks glycolysis and oxidative phosphorylation is unknown, we definitively show that HSCs require de novo lipogenesis for activation. Consistent with this direct antifibrotic mechanism in HSCs, ACC inhibition reduced liver fibrosis in a rat choline-deficient, high-fat diet model and in response to chronic diethylnitrosamine-induced liver injury (in the absence of hepatic lipid accumulation). CONCLUSIONS: In addition to reducing lipid accumulation in hepatocytes, ACC inhibition also directly impairs the profibrogenic activity of HSCs. Thus, small molecule inhibitors of ACC may lessen fibrosis by reducing lipotoxicity in hepatocytes and by preventing HSC activation, providing a mechanistic rationale for the treatment of patients with advanced liver fibrosis due to NASH. LAY SUMMARY: Hepatic fibrosis is the most important predictor of liver-related outcomes in patients with non-alcoholic steatohepatitis (NASH). Small molecule inhibitors of acetyl-CoA carboxylase (ACC) reduce hepatic fat content and markers of liver injury in patients with NASH. Herein, we report that inhibition of ACC and de novo lipogenesis also directly suppress the activation of hepatic stellate cells - the primary cell responsible for generating fibrotic scar in the liver - and thus fibrosis. These data provide further evidence for the use of ACC inhibitors to treat patients with NASH and advanced fibrosis.
Asunto(s)
Acetil-CoA Carboxilasa/antagonistas & inhibidores , Células Estrelladas Hepáticas/metabolismo , Lipogénesis/efectos de los fármacos , Cirrosis Hepática/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Animales , Biomarcadores/metabolismo , Línea Celular , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/patología , Humanos , Hígado/metabolismo , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Ratas , Ratas WistarRESUMEN
Farnesoid X receptor (FXR) is a nuclear receptor that has emerged as a key regulator in the maintenance of hepatic steatosis, inflammation, and fibrosis. However, the role of FXR in renal fibrosis remains to be established. Here, we investigate the effects of the FXR agonist EDP-305 in a mouse model of tubulointerstitial fibrosis via unilateral ureteral obstruction (UUO). Male C57Bl/6 mice received a UUO on their left kidney. On postoperative d 4, mice received daily treatment by oral gavage with either vehicle control (0.5% methylcellulose) or 10 or 30 mg/kg EDP-305. All animals were euthanized on postoperative d 12. EDP-305 dose-dependently decreased macrophage infiltration as measured by the F4/80 staining area and proinflammatory cytokine gene expression. EDP-305 also dose-dependently reduced interstitial fibrosis as assessed by morphometric quantification of the collagen proportional area and kidney hydroxyproline levels. Finally, yes-associated protein (YAP) activation, a major driver of fibrosis, increased after UUO injury and was diminished by EDP-305 treatment. Consistently, EDP-305 decreased TGF-ß1-induced YAP nuclear localization in human kidney 2 cells by increasing inhibitory YAP phosphorylation. YAP inhibition may be a novel antifibrotic mechanism of FXR agonism, and EDP-305 could be used to treat renal fibrosis.-Li, S., Ghoshal, S., Sojoodi, M., Arora, G., Masia, R., Erstad, D. J., Ferriera, D. S., Li, Y., Wang, G., Lanuti, M., Caravan, P., Or, Y. S., Jiang, L.-J., Tanabe, K. K., Fuchs, B. C. The farnesoid X receptor agonist EDP-305 reduces interstitial renal fibrosis in a mouse model of unilateral ureteral obstruction.
Asunto(s)
Fibrosis/etiología , Fibrosis/prevención & control , Enfermedades Renales/etiología , Enfermedades Renales/prevención & control , Receptores Citoplasmáticos y Nucleares/agonistas , Esteroides/farmacología , Obstrucción Ureteral/complicaciones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Esteroides/uso terapéutico , Proteínas Señalizadoras YAPRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the deadliest malignancies worldwide due to the lack of effective treatments. Chemoprevention in high-risk patients is a promising, alternative strategy. In this study, pioglitazone was investigated for its ability to prevent hepatocarcinogenesis in two rodent models of cirrhosis. METHODS: In the first model, male Wistar rats were given repeated, low-dose injections of diethylnitrosamine (DEN) to accurately recapitulate the progression of fibrosis to cirrhosis and HCC. In the second model, a single dose of DEN was administered to male C57Bl/6 pups at day fifteen followed by administration of a choline-deficient, L-amino acid defined, high-fat diet (CDAHFD) at week six for 24 weeks. Pioglitazone treatment started at the first signs of fibrosis in both models. RESULTS: Pioglitazone effectively reduced fibrosis progression and HCC development in both models. Gross tumor nodules were significantly reduced after pioglitazone treatment (7.4 ± 1.6 vs. 16.6 ± 2.6 in the rat DEN model and 5.86 ± 1.82 vs. 13.2 ± 1.25 in the mouse DEN+CDAHFD model). In both models, pioglitazone reduced the activation of mitogen-activated protein kinase (MAPK) and upregulated the hepato-protective AMP-activated protein kinase (AMPK) pathway via increasing circulating adiponectin production. CONCLUSION: Pioglitazone is an effective agent for chemoprevention in rodents and could be repurposed as a multi-targeted drug for delaying liver fibrosis and hepatocarcinogenesis.
Asunto(s)
Carcinoma Hepatocelular/prevención & control , Hipoglucemiantes/uso terapéutico , Neoplasias Hepáticas/prevención & control , Pioglitazona/uso terapéutico , Proteínas Quinasas Activadas por AMP/metabolismo , Adiponectina/sangre , Animales , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Colina/administración & dosificación , Dieta Alta en Grasa , Dietilnitrosamina , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacosRESUMEN
The incidence of hepatocellular carcinoma (HCC) is rapidly increasing due to the prevalence of obesity and non-alcoholic fatty liver disease, but the molecular triggers that initiate disease development are not fully understood. We demonstrate that mice with targeted loss-of-function point mutations within the AMP-activated protein kinase (AMPK) phosphorylation sites on acetyl-CoA carboxylase 1 (ACC1 Ser79Ala) and ACC2 (ACC2 Ser212Ala) have increased liver de novo lipogenesis (DNL) and liver lesions. The same mutation in ACC1 also increases DNL and proliferation in human liver cancer cells. Consistent with these findings, a novel, liver-specific ACC inhibitor (ND-654) that mimics the effects of ACC phosphorylation inhibits hepatic DNL and the development of HCC, improving survival of tumor-bearing rats when used alone and in combination with the multi-kinase inhibitor sorafenib. These studies highlight the importance of DNL and dysregulation of AMPK-mediated ACC phosphorylation in accelerating HCC and the potential of ACC inhibitors for treatment.
Asunto(s)
Acetil-CoA Carboxilasa , Carcinoma Hepatocelular/metabolismo , Lipogénesis , Neoplasias Hepáticas/metabolismo , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Acetil-CoA Carboxilasa/fisiología , Animales , Células Hep G2 , Humanos , Masculino , Ratones , Fosforilación , Ratas , Ratas WistarRESUMEN
We examined a novel farnesoid X receptor agonist, EDP-305, for its antifibrotic effect in bile duct ligation (BDL) and choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) models of hepatic injury. We used molecular magnetic resonance imaging with the type 1 collagen-binding probe EP-3533 and the oxidized collagen-specific probe gadolinium hydrazide to noninvasively measure treatment response. BDL rats (n = 8 for each group) were treated with either low or high doses of EDP-305 starting on day 4 after BDL and were imaged on day 18. CDAHFD mice (n = 8 for each group) were treated starting at 6 weeks after the diet and were imaged at 12 weeks. Liver tissue was subjected to pathologic and morphometric scoring of fibrosis, hydroxyproline quantitation, and determination of fibrogenic messenger RNA expression. High-dose EDP-305 (30 mg/kg) reduced liver fibrosis in both the BDL and CDAHFD models as measured by collagen proportional area, hydroxyproline analysis, and fibrogenic gene expression (all P < 0.05). Magnetic resonance signal intensity with both EP-3533 in the BDL model and gadolinium hydrazide in the CDAHFD model was reduced with EDP-305 30 mg/kg treatment (P < 0.01). Histologically, EDP-305 30 mg/kg halted fibrosis progression in the CDAHFD model. Conclusion: EDP-305 reduced fibrosis progression in rat BDL and mouse CDAHFD models. Molecular imaging of collagen and oxidized collagen is sensitive to changes in fibrosis and could be used to noninvasively measure treatment response in clinical trials. (Hepatology Communications 2018;2:821-835).
RESUMEN
Syngeneic, immunocompetent allograft tumor models recapitulate important aspects of the tumor microenvironment and have short tumor latency with predictable growth kinetics, making them useful for trialing novel therapeutics. Here, we describe surgical techniques for orthotopic and heterotopic pancreatic ductal adenocarcinoma (PDAC) tumor implantation and characterize phenotypes based on implantation site.Mice (n=8 per group) were implanted with 104 cells in the pancreas or flank. Hy15549 and Han4.13 cell lines were derived from primary murine PDAC (Ptf1-Cre; LSL-KRAS-G12D; Trp53 Lox/+) on C57BL/6 and FVB strains, respectively. Single-cell suspension and solid tumor implants were compared. Tumors were treated with two intravenous doses of FOLFIRINOX and responses evaluated.All mice developed pancreatic tumors within 7â days. Orthotopic tumors grew faster and larger than heterotopic tumors. By 3â weeks, orthotopic mice began losing weight, and showed declines in body condition requiring euthanasia starting at 4â weeks. Single-cell injection into the pancreas had near 100% engraftment, but solid tumor implant engraftment was â¼50% and was associated with growth restriction. Orthotopic tumors were significantly more responsive to intravenous FOLFIRINOX compared with heterotopic tumors, with greater reductions in size and increased apoptosis. Heterotopic tumors were more desmoplastic and hypovascular. However, drug uptake into tumor tissue was equivalent regardless of tumor location or degree of fibrosis, indicating that microenvironment differences between heterotopic and orthotopic tumors influenced response to therapy.Our results show that orthotopic and heterotopic allograft locations confer unique microenvironments that influence growth kinetics, desmoplastic response and angiogenesis. Tumor location influences chemosensitivity to FOLFIRINOX and should inform future preclinical trials.This article has an associated First Person interview with the first author of the paper.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fluorouracilo/uso terapéutico , Leucovorina/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Aloinjertos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Autoinjertos , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Combinación de Medicamentos , Fluorouracilo/administración & dosificación , Fluorouracilo/farmacología , Humanos , Irinotecán , Cinética , Leucovorina/administración & dosificación , Leucovorina/farmacología , Masculino , Ratones Endogámicos C57BL , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/farmacología , Oxaliplatino , Neoplasias Pancreáticas/irrigación sanguínea , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Fenotipo , Trasplante HeterotópicoRESUMEN
Activation of hepatic stellate cells (HSCs) in response to injury is a key step in hepatic fibrosis, and is characterized by trans-differentiation of quiescent HSCs to HSC myofibroblasts, which secrete extracellular matrix proteins responsible for the fibrotic scar. There are currently no therapies to directly inhibit hepatic fibrosis. We developed a small molecule screen to identify compounds that inactivate human HSC myofibroblasts through the quantification of lipid droplets. We screened 1600 compounds and identified 21 small molecules that induce HSC inactivation. Four hits were tricyclic antidepressants (TCAs), and they repressed expression of pro-fibrotic factors Alpha-Actin-2 (ACTA2) and Alpha-1 Type I Collagen (COL1A1) in HSCs. RNA sequencing implicated the sphingolipid pathway as a target of the TCAs. Indeed, TCA treatment of HSCs promoted accumulation of ceramide through inhibition of acid ceramidase (aCDase). Depletion of aCDase also promoted accumulation of ceramide and was associated with reduced COL1A1 expression. Treatment with B13, an inhibitor of aCDase, reproduced the antifibrotic phenotype as did the addition of exogenous ceramide. Our results show that detection of lipid droplets provides a robust readout to screen for regulators of hepatic fibrosis and have identified a novel antifibrotic role for ceramide.
Asunto(s)
Antidepresivos Tricíclicos/farmacología , Ceramidas/metabolismo , Colágeno/biosíntesis , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Descubrimiento de Drogas/métodos , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Humanos , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/etiología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Miofibroblastos/efectos de los fármacos , Miofibroblastos/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
Cirrhosis is a milieu that develops hepatocellular carcinoma (HCC), the second most lethal cancer worldwide. HCC prediction and prevention in cirrhosis are key unmet medical needs. Here we have established an HCC risk gene signature applicable to all major HCC etiologies: hepatitis B/C, alcohol, and non-alcoholic steatohepatitis. A transcriptome meta-analysis of >500 human cirrhotics revealed global regulatory gene modules driving HCC risk and the lysophosphatidic acid pathway as a central chemoprevention target. Pharmacological inhibition of the pathway in vivo reduced tumors and reversed the gene signature, which was verified in organotypic ex vivo culture of patient-derived fibrotic liver tissues. These results demonstrate the utility of clinical organ transcriptome to enable a strategy, namely, reverse-engineering precision cancer prevention.
Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/prevención & control , Perfilación de la Expresión Génica/métodos , Cirrosis Hepática/genética , Neoplasias Hepáticas/prevención & control , Lisofosfolípidos/biosíntesis , Animales , Antineoplásicos/farmacología , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Redes Reguladoras de Genes , Predisposición Genética a la Enfermedad , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/genética , Ratas , Factores de Riesgo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Cancer stem cell (CSC) marker CD133 was found to be upregulated in many cancers including hepatocellular carcinoma (HCC). However, the molecular mechanism of CD133 regulation in the liver tumor microenvironment has remained elusive. In this study Won and colleagues report that interleukin-6 (IL-6) mediated signal transducer and activator of transcription factor 3 (STAT3) signaling and hypoxia enhance the expression of CD133 and promote the progression of HCC.
RESUMEN
Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, the most frequent of which is F508del-CFTR. CF is characterized by excessive secretion of pro-inflammatory mediators into the airway lumen, inducing a highly inflammatory cellular phenotype. This process triggers fibrosis, causing airway destruction and leading to high morbidity and mortality. We previously reported that miR-155 is upregulated in CF lung epithelial cells, but the molecular mechanisms by which miR-155 affects the disease phenotype is not understood. Here we report that RPTOR (regulatory associated protein of mTOR, complex 1) is a novel target of miR-155 in CF lung epithelial cells. The suppression of RPTOR expression and subsequent activation of TGF-ß signaling resulted in the induction of fibrosis by elevating connective tissue growth factor (CTGF) abundance in CF lung epithelial cells. Thus, we propose that miR-155 might regulate fibrosis of CF lungs through the increased CTGF expression, highlighting its potential value in CF therapy.
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Proteínas Adaptadoras Transductoras de Señales/genética , Factor de Crecimiento del Tejido Conjuntivo/genética , Fibrosis Quística/genética , Regulación de la Expresión Génica , Pulmón/metabolismo , MicroARNs/genética , Mucosa Respiratoria/metabolismo , Regiones no Traducidas 3' , Línea Celular , Fibrosis Quística/metabolismo , Fibrosis Quística/patología , Humanos , Pulmón/patología , Modelos Biológicos , Fenotipo , Interferencia de ARN , ARN Mensajero/genética , Proteína Reguladora Asociada a mTOR , Reproducibilidad de los Resultados , Mucosa Respiratoria/patología , Transducción de SeñalRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC)-associated mortality is increasing at an alarming rate, and there is a readily identifiable cohort of at-risk patients with cirrhosis, viral hepatitis, nonalcoholic fatty liver disease, and diabetes. These patients are candidates for chemoprevention. Metformin is an attractive agent for chemoprevention because it is inexpensive, has a favorable safety profile, and is well tolerated over long time periods. METHODS: The authors studied the efficacy of metformin as a prevention agent in a clinically relevant rat model of HCC, in which tumors develop in the setting of chronic inflammation and cirrhosis. Repeated injections of diethylnitrosamine were used to induce sequential cirrhosis and HCC, and metformin was administered at the first signs of either fibrosis or cirrhosis. RESULTS: Prolonged metformin exposure was safe and was associated with decreases in fibrotic and inflammatory markers, especially when administered early at the first signs of fibrosis. In addition, early metformin treatment led to a 44% decrease in HCC incidence, whereas tumor burden was unchanged when metformin was administered at the first signs of cirrhosis. It is noteworthy that activation of the hepatic progenitor/stem cell compartment was first observed at the onset of cirrhosis; therefore, only early metformin treatment suppressed receptor for advanced glycation end products and inhibited the activation of hepatic progenitor cells. CONCLUSIONS: The current results are the first to demonstrate an effect on progenitor/stem cells in the setting of chemoprevention and provide further rationale to explore metformin as an early intervention in clinical trials of patients with chronic liver disease at high risk for HCC.
Asunto(s)
Carcinoma Hepatocelular/prevención & control , Transformación Celular Neoplásica/efectos de los fármacos , Cirrosis Hepática/tratamiento farmacológico , Neoplasias Hepáticas/prevención & control , Metformina/farmacología , Células Madre/efectos de los fármacos , Animales , Biopsia con Aguja , Western Blotting , Carcinoma Hepatocelular/patología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Inmunohistoquímica , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Masculino , Reacción en Cadena de la Polimerasa/métodos , Distribución Aleatoria , Ratas , Ratas Wistar , Valores de Referencia , Células Madre/citología , Resultado del TratamientoRESUMEN
In vertebrates, phosphocreatine and ATP are continuously interconverted by the reversible reaction of creatine kinase in accordance with cellular energy needs. Sarcoma tissue and its normal counterpart, creatine-rich skeletal muscle, are good source materials to study the status of creatine and creatine kinase with the progression of malignancy. We experimentally induced sarcoma in mouse leg muscle by injecting either 3-methylcholanthrene or live sarcoma 180 cells into one hind leg. Creatine, phosphocreatine and creatine kinase isoform levels decreased as malignancy progressed and reached very low levels in the final stage of sarcoma development; all these parameters remained unaltered in the unaffected contralateral leg muscle of the same animal. Creatine and creatine kinase levels were also reduced significantly in frank malignant portions of human sarcoma and gastric and colonic adenocarcinoma compared with the distal nonmalignant portions of the same samples. In mice, immunoblotting with antibodies against cytosolic muscle-type creatine kinase and sarcomeric mitochondrial creatine kinase showed that both of these isoforms decreased as malignancy progressed. Expressions of mRNA of muscle-type creatine kinase and sarcomeric mitochondrial creatine kinase were also severely downregulated. In human sarcoma these two isoforms were undetectable also. In human gastric and colonic adenocarcinoma, brain-type creatine kinase was found to be downregulated, whereas ubiquitous mitochondrial creatine kinase was upregulated. These significantly decreased levels of creatine and creatine kinase isoforms in sarcoma suggest that: (a) the genuine muscle phenotype is lost during sarcoma progression, and (b) these parameters may be used as diagnostic marker and prognostic indicator of malignancy in this tissue.
Asunto(s)
Transformación Celular Neoplásica/metabolismo , Creatina Quinasa/metabolismo , Creatina/metabolismo , Músculo Esquelético/metabolismo , Neoplasias de Tejido Muscular/metabolismo , Fosfocreatina/metabolismo , Sarcoma/metabolismo , Adenocarcinoma/enzimología , Animales , Neoplasias Colorrectales/enzimología , Creatina Quinasa/análisis , Creatina Quinasa/genética , Forma BB de la Creatina-Quinasa/análisis , Forma MM de la Creatina-Quinasa/análisis , Forma Mitocondrial de la Creatina-Quinasa/análisis , Progresión de la Enfermedad , Humanos , Immunoblotting , Ratones , Músculo Esquelético/enzimología , Neoplasias de Tejido Muscular/enzimología , Neoplasias de Tejido Muscular/patología , ARN Mensajero/metabolismo , Sarcoma/enzimología , Sarcoma Experimental/enzimología , Sarcoma Experimental/metabolismo , Sarcoma Experimental/patología , Neoplasias Gástricas/enzimologíaRESUMEN
Silk fibroin from silk gland of Bombyx mori 5th instar larvae was utilized to fabricate films, which may find possible applications as two-dimensional matrices for tissue engineering. Bombyx mori cocoon fibroin is well characterized as potential biomaterial by virtue of its good mechanical strength, water stability, thermal properties, surface roughness and biocompatibility. The present study aims to characterize the biophysical, thermal, mechanical, rheological, swelling properties along with spectroscopic analysis, surface morphology and biocompatibility of the silk gland fibroin films compared with cocoon fibroin. Fibroin solutions showed increased turbidity and shear thinning at higher concentration. The films after methanol treatment swelled moderately and were less hydrophilic compared to the untreated. The spectroscopic analysis of the films illustrated the presence of various amide peaks and conformational transition from random coil to beta sheet on methanol treatment. X-ray diffraction studies also confirmed the secondary structure. Thermogravimetric analysis showed distinct weight loss of the films. The films were mechanically stronger and AFM studies showed surfaces were rougher on methanol treatment. The matrices were biocompatible and supported L929 mouse fibroblast cell growth and proliferation. The results substantiate the silk gland fibroin films as potential biomaterial matrices.