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1.
Cell ; 186(13): 2823-2838.e20, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37236193

RESUMO

Mental health profoundly impacts inflammatory responses in the body. This is particularly apparent in inflammatory bowel disease (IBD), in which psychological stress is associated with exacerbated disease flares. Here, we discover a critical role for the enteric nervous system (ENS) in mediating the aggravating effect of chronic stress on intestinal inflammation. We find that chronically elevated levels of glucocorticoids drive the generation of an inflammatory subset of enteric glia that promotes monocyte- and TNF-mediated inflammation via CSF1. Additionally, glucocorticoids cause transcriptional immaturity in enteric neurons, acetylcholine deficiency, and dysmotility via TGF-ß2. We verify the connection between the psychological state, intestinal inflammation, and dysmotility in three cohorts of IBD patients. Together, these findings offer a mechanistic explanation for the impact of the brain on peripheral inflammation, define the ENS as a relay between psychological stress and gut inflammation, and suggest that stress management could serve as a valuable component of IBD care.


Assuntos
Sistema Nervoso Entérico , Doenças Inflamatórias Intestinais , Humanos , Glucocorticoides/farmacologia , Inflamação , Sistema Nervoso Entérico/fisiologia , Estresse Psicológico
2.
Nature ; 611(7937): 780-786, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36385534

RESUMO

Enteric pathogens are exposed to a dynamic polymicrobial environment in the gastrointestinal tract1. This microbial community has been shown to be important during infection, but there are few examples illustrating how microbial interactions can influence the virulence of invading pathogens2. Here we show that expansion of a group of antibiotic-resistant, opportunistic pathogens in the gut-the enterococci-enhances the fitness and pathogenesis of Clostridioides difficile. Through a parallel process of nutrient restriction and cross-feeding, enterococci shape the metabolic environment in the gut and reprogramme C. difficile metabolism. Enterococci provide fermentable amino acids, including leucine and ornithine, which increase C. difficile fitness in the antibiotic-perturbed gut. Parallel depletion of arginine by enterococci through arginine catabolism provides a metabolic cue for C. difficile that facilitates increased virulence. We find evidence of microbial interaction between these two pathogenic organisms in multiple mouse models of infection and patients infected with C. difficile. These findings provide mechanistic insights into the role of pathogenic microbiota in the susceptibility to and the severity of C. difficile infection.


Assuntos
Clostridioides difficile , Enterococcus , Interações Microbianas , Animais , Humanos , Camundongos , Antibacterianos/farmacologia , Arginina/deficiência , Arginina/metabolismo , Clostridioides difficile/metabolismo , Clostridioides difficile/patogenicidade , Clostridioides difficile/fisiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Enterococcus/metabolismo , Enterococcus/patogenicidade , Enterococcus/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Intestinos/microbiologia , Leucina/metabolismo , Ornitina/metabolismo , Virulência , Suscetibilidade a Doenças
3.
Nature ; 605(7908): 160-165, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35477756

RESUMO

Colorectal cancer (CRC) is among the most frequent forms of cancer, and new strategies for its prevention and therapy are urgently needed1. Here we identify a metabolite signalling pathway that provides actionable insights towards this goal. We perform a dietary screen in autochthonous animal models of CRC and find that ketogenic diets exhibit a strong tumour-inhibitory effect. These properties of ketogenic diets are recapitulated by the ketone body ß-hydroxybutyrate (BHB), which reduces the proliferation of colonic crypt cells and potently suppresses intestinal tumour growth. We find that BHB acts through the surface receptor Hcar2 and induces the transcriptional regulator Hopx, thereby altering gene expression and inhibiting cell proliferation. Cancer organoid assays and single-cell RNA sequencing of biopsies from patients with CRC provide evidence that elevated BHB levels and active HOPX are associated with reduced intestinal epithelial proliferation in humans. This study thus identifies a BHB-triggered pathway regulating intestinal tumorigenesis and indicates that oral or systemic interventions with a single metabolite may complement current prevention and treatment strategies for CRC.


Assuntos
Neoplasias Colorretais , Transdução de Sinais , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/farmacologia , Animais , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/prevenção & controle , Humanos
4.
Cancer ; 130(3): 476-484, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823514

RESUMO

BACKGROUND: In select patients, pancreatic adenocarcinoma remains a local disease, yet there are no validated biomarkers to predict this behavior and who may benefit from aggressive local treatments. This study sought to determine if SMAD4 (mothers against decapentaplegic homolog 4) messenger RNA-sequencing (RNA-seq) expression is a robust method for predicting overall survival (OS) and distant metastasis-free survival (DMFS) in patients with resected pancreatic adenocarcinoma. METHODS: Utilizing The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC), 322 patients with resected stage I-III pancreatic adenocarcinoma were identified. In TCGA, multivariable proportional hazards models were used to determine the association of SMAD4 genomic aberrations and RNA-seq expression with OS and DMFS. In the ICGC, analysis sought to confirm the predictive performance of RNA-seq via multivariable models and receiver operator characteristic curves. RESULTS: In TCGA, the presence of SMAD4 genomic aberrations was associated with worse OS (hazard ratio [HR], 1.55; 95% CI, 1.00-2.40; p = .048) but not DMFS (HR, 1.33; 95% CI, .87-2.03; p = .19). Low SMAD4 RNA-seq expression was associated with worse OS (HR, 1.83; 95% CI, 1.17-2.86; p = .008) and DMFS (HR, 1.70; 95% CI, 1.14-2.54; p = .009). In the ICGC, increased SMAD4 RNA-seq expression correlated with improved OS (area under the curve [AUC], .92; 95% CI, .86-.94) and DMFS (AUC, .84; 95% CI, .82-.87). CONCLUSIONS: In patients with resected pancreatic adenocarcinoma, SMAD4 genomic aberrations are associated with worse OS but do not predict for DMFS. Increased SMAD4 RNA-seq expression is associated with improved OS and DMFS in patients with resected pancreatic adenocarcinoma. This reproducible finding suggests SMAD4 RNA-seq expression may be a useful marker to predict metastatic spread.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , Proteína Smad4/genética , Modelos de Riscos Proporcionais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Prognóstico
5.
J Hepatol ; 79(6): 1396-1407, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37611641

RESUMO

BACKGROUND & AIMS: Biliary atresia (BA) is an obstructive cholangiopathy that initially affects the extrahepatic bile ducts (EHBDs) of neonates. The etiology is uncertain, but evidence points to a prenatal cause. Fetal tissues have increased levels of hyaluronic acid (HA), which plays an integral role in fetal wound healing. The objective of this study was to determine whether a program of fetal wound healing is part of the response to fetal EHBD injury. METHODS: Mouse, rat, sheep, and human EHBD samples were studied at different developmental time points. Models included a fetal sheep model of prenatal hypoxia, human BA EHBD remnants and liver samples taken at the time of the Kasai procedure, EHBDs isolated from neonatal rats and mice, and spheroids and other models generated from primary neonatal mouse cholangiocytes. RESULTS: A wide layer of high molecular weight HA encircling the lumen was characteristic of the normal perinatal but not adult EHBD. This layer, which was surrounded by collagen, expanded in injured ducts in parallel with extensive peribiliary gland hyperplasia, increased mucus production and elevated serum bilirubin levels. BA EHBD remnants similarly showed increased HA centered around ductular structures compared with age-appropriate controls. High molecular weight HA typical of the fetal/neonatal ducts caused increased cholangiocyte spheroid growth, whereas low molecular weight HA induced abnormal epithelial morphology; low molecular weight HA caused matrix swelling in a bile duct-on-a-chip device. CONCLUSION: The fetal/neonatal EHBD, including in human EHBD remnants from Kasai surgeries, demonstrated an injury response with prolonged high levels of HA typical of fetal wound healing. The expanded peri-luminal HA layer may swell and lead to elevated bilirubin levels and obstruction of the EHBD. IMPACT AND IMPLICATIONS: Biliary atresia is a pediatric cholangiopathy associated with high morbidity and mortality rates; although multiple etiologies have been proposed, the fetal response to bile duct damage is largely unknown. This study explores the fetal pathogenesis after extrahepatic bile duct damage, thereby opening a completely new avenue to study therapeutic targets in the context of biliary atresia.


Assuntos
Ductos Biliares Extra-Hepáticos , Atresia Biliar , Humanos , Animais , Camundongos , Ratos , Criança , Ovinos , Atresia Biliar/patologia , Ductos Biliares Extra-Hepáticos/patologia , Feto/patologia , Cicatrização , Bilirrubina
6.
Radiology ; 303(1): 215-225, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35014906

RESUMO

Background Transarterial embolization (TAE) is the most common treatment for hepatocellular carcinoma (HCC); however, there remain limited data describing the influence of TAE on the tumor immune microenvironment. Purpose To characterize TAE-induced modulation of the tumor immune microenvironment in a rat model of HCC and identify factors that modulate this response. Materials and Methods TAE was performed on autochthonous HCCs induced in rats with use of diethylnitrosamine. CD3, CD4, CD8, and FOXP3 lymphocytes, as well as programmed cell death protein ligand-1 (PD-L1) expression, were examined in three cohorts: tumors from rats that did not undergo embolization (control), embolized tumors (target), and nonembolized tumors from rats that had a different target tumor embolized (nontarget). Differences in immune cell recruitment associated with embolic agent type (tris-acryl gelatin microspheres [TAGM] vs hydrogel embolics) and vascular location were examined in rat and human tissues. A generalized estimating equation model and t, Mann-Whitney U, and χ2 tests were used to compare groups. Results Cirrhosis-induced alterations in CD8, CD4, and CD25/CD4 lymphocytes were partially normalized following TAE (CD8: 38.4%, CD4: 57.6%, and CD25/CD4: 21.1% in embolized liver vs 47.7% [P = .02], 47.0% [P = .01], and 34.9% [P = .03], respectively, in cirrhotic liver [36.1%, 59.6%, and 4.6% in normal liver]). Embolized tumors had a greater number of CD3, CD4, and CD8 tumor-infiltrating lymphocytes relative to controls (191.4 cells/mm2 vs 106.7 cells/mm2 [P = .03]; 127.8 cells/mm2 vs 53.8 cells/mm2 [P < .001]; and 131.4 cells/mm2 vs 78.3 cells/mm2 [P = .01]) as well as a higher PD-L1 expression score (4.1 au vs 1.9 au [P < .001]). A greater number of CD3, CD4, and CD8 lymphocytes were found near TAGM versus hydrogel embolics (4.1 vs 2.0 [P = .003]; 3.7 vs 2.0 [P = .01]; and 2.2 vs 1.1 [P = .03], respectively). The number of lymphocytes adjacent to embolics differed based on vascular location (17.9 extravascular CD68+ peri-TAGM cells vs 7.0 intravascular [P < .001]; 6.4 extravascular CD68+ peri-hydrogel embolic cells vs 3.4 intravascular [P < .001]). Conclusion Transarterial embolization-induced dynamic alterations of the tumor immune microenvironment are influenced by underlying liver disease, embolic agent type, and vascular location. © RSNA, 2022 Online supplemental material is available for this article. See also the editorials by Kennedy et al and by White in this issue.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Antígeno B7-H1 , Carcinoma Hepatocelular/patologia , Humanos , Hidrogéis , Imunidade , Neoplasias Hepáticas/patologia , Ratos , Microambiente Tumoral
7.
Hepatology ; 74(6): 3427-3440, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34233020

RESUMO

BACKGROUND AND AIMS: Although germ-free mice are an indispensable tool in studying the gut microbiome and its effects on host physiology, they are phenotypically different than their conventional counterparts. While antibiotic-mediated microbiota depletion in conventional mice leads to physiologic alterations that often mimic the germ-free state, the degree to which the effects of microbial colonization on the host are reversible is unclear. The gut microbiota produce abundant short chain fatty acids (SCFAs), and previous studies have demonstrated a link between microbial-derived SCFAs and global hepatic histone acetylation in germ-free mice. APPROACH AND RESULTS: We demonstrate that global hepatic histone acetylation states measured by mass spectrometry remained largely unchanged despite loss of luminal and portal vein SCFAs after antibiotic-mediated microbiota depletion. In contrast to stable hepatic histone acetylation states, we see robust hepatic transcriptomic alterations after microbiota depletion. Additionally, neither dietary supplementation with supraphysiologic levels of SCFA nor the induction of hepatocyte proliferation in the absence of microbiota-derived SCFAs led to alterations in global hepatic histone acetylation. CONCLUSIONS: These results suggest that microbiota-dependent landscaping of the hepatic epigenome through global histone acetylation is static in nature, while the hepatic transcriptome is responsive to alterations in the gut microbiota.


Assuntos
Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/fisiologia , Histona Acetiltransferases/metabolismo , Animais , Linhagem Celular , Masculino , Camundongos Endogâmicos C57BL
8.
Gastroenterology ; 158(8): 2221-2235.e5, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32113825

RESUMO

BACKGROUND & AIMS: Small, 2-dimensional sections routinely used for human pathology analysis provide limited information about bowel innervation. We developed a technique to image human enteric nervous system (ENS) and other intramural cells in 3 dimensions. METHODS: Using mouse and human colon tissues, we developed a method that combines tissue clearing, immunohistochemistry, confocal microscopy, and quantitative analysis of full-thickness bowel without sectioning to quantify ENS and other intramural cells in 3 dimensions. RESULTS: We provided 280 adult human colon confocal Z-stacks from persons without known bowel motility disorders. Most of our images were of myenteric ganglia, captured using a 20× objective lens. Full-thickness colon images, viewed with a 10× objective lens, were as large as 4 × 5 mm2. Colon from 2 pediatric patients with Hirschsprung disease was used to show distal colon without enteric ganglia, as well as a transition zone and proximal pull-through resection margin where ENS was present. After testing a panel of antibodies with our method, we identified 16 antibodies that bind to molecules in neurons, glia, interstitial cells of Cajal, and muscularis macrophages. Quantitative analyses demonstrated myenteric plexus in 24.5% ± 2.4% of flattened colon Z-stack area. Myenteric ganglia occupied 34% ± 4% of myenteric plexus. Single myenteric ganglion volume averaged 3,527,678 ± 573,832 mm3 with 38,706 ± 5763 neuron/mm3 and 129,321 ± 25,356 glia/mm3. Images of large areas provided insight into why published values of ENS density vary up to 150-fold-ENS density varies greatly, across millimeters, so analyses of small numbers of thin sections from the same bowel region can produce varying results. Neuron subtype analysis revealed that approximately 56% of myenteric neurons stained with neuronal nitric oxide synthase antibody and approximately 33% of neurons produce and store acetylcholine. Transition zone regions from colon tissues of patients with Hirschsprung disease had ganglia in multiple layers and thick nerve fiber bundles without neurons. Submucosal neuron distribution varied among imaged colon regions. CONCLUSIONS: We developed a 3-dimensional imaging method for colon that provides more information about ENS structure than tissue sectioning. This approach could improve diagnosis for human bowel motility disorders and may be useful for other bowel diseases as well.


Assuntos
Colo/inervação , Gânglios Autônomos/patologia , Doença de Hirschsprung/patologia , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Microscopia Confocal , Plexo Mientérico/patologia , Plexo Submucoso/patologia , Animais , Automação , Neurônios Colinérgicos/patologia , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Nitrérgicos/patologia , Valor Preditivo dos Testes , Fixação de Tecidos
9.
Liver Transpl ; 27(9): 1248-1261, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33853207

RESUMO

Transplant eligibility for hepatocellular carcinoma (HCC) is determined by the imaging identification of tumor burden within the Milan criteria. Transjugular intrahepatic portosystemic shunt(s) (TIPS) reduce portal hypertension but may impact HCC visualization. It was hypothesized that the presence of pretransplant TIPS would correlate with occult HCC and reduced survival. A single-center, retrospective, case control study was performed among liver transplant recipients with HCC (2000-2017). The primary endpoint was occult disease on explant pathology. Backward stepwise logistic regression was performed. The secondary endpoints disease-free survival (DFS) and overall survival (OS) were evaluated with Kaplan-Meier curves and Cox regression analysis. Of 640 patients, 40 had TIPS and more frequently exhibited occult disease (80.0% versus 43.1%; P < 0.001; odds ratio [OR], 4.16; P < 0.001). Portal vein thrombosis (PVT) similarly correlated with occult disease (OR, 1.97; P = 0.02). Explant tumor burden was equivalent between TIPS subgroups; accordingly, TIPS status was not independently associated with reduced DFS or OS. However, exceeding the Milan criteria was associated with reduced DFS (hazard ratio, 3.21; P = 0.001), and TIPS status in patients with a single suspected lesion (n = 316) independently correlated with explant tumor burdens beyond these criteria (OR, 13.47; P = 0.001). TIPS on pretransplant imaging are associated with occult HCC on explant pathology. Comparable occult disease findings in patients with PVT suggest that the mechanism may involve altered hepatic perfusion, obscuring imaging diagnosis. TIPS are not independently associated with reduced DFS or OS but are associated with exceeding the Milan criteria for patients with a single suspected lesion. The presence of TIPS may necessitate a higher index of suspicion for occult HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática , Carcinoma Hepatocelular/cirurgia , Estudos de Casos e Controles , Humanos , Cirrose Hepática , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Veia Porta/diagnóstico por imagem , Veia Porta/cirurgia , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
10.
Hepatology ; 72(1): 140-154, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31553806

RESUMO

BACKGROUND AND AIMS: Advances in cancer treatment have improved survival; however, local recurrence and metastatic disease-the principal causes of cancer mortality-have limited the ability to achieve durable remissions. Local recurrences arise from latent tumor cells that survive therapy and are often not detectable by conventional clinical imaging techniques. Local recurrence after transarterial embolization (TAE) of hepatocellular carcinoma (HCC) provides a compelling clinical correlate of this phenomenon. In response to TAE-induced ischemia, HCC cells adapt their growth program to effect a latent phenotype that precedes local recurrence. APPROACH AND RESULTS: In this study, we characterized and leveraged the metabolic reprogramming demonstrated by latent HCC cells in response to TAE-induced ischemia to enable their detection in vivo using dynamic nuclear polarization (DNP) magnetic resonance spectroscopic imaging (MRSI) of 13 carbon-labeled substrates. Under TAE-induced ischemia, latent HCC cells demonstrated reduced metabolism and developed a dependence on glycolytic flux to lactate. Despite the hypometabolic state of these cells, DNP-MRSI of 1-13 C-pyruvate and its downstream metabolites, 1-13 C-lactate and 1-13 C-alanine, predicted histological viability. CONCLUSIONS: These studies provide a paradigm for imaging latent, treatment-refractory cancer cells, suggesting that DNP-MRSI provides a technology for this application.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Embolização Terapêutica , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Wistar
11.
J Lipid Res ; 61(7): 983-994, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32398264

RESUMO

Alcohol's impairment of both hepatic lipid metabolism and insulin resistance (IR) are key drivers of alcoholic steatosis, the initial stage of alcoholic liver disease (ALD). Pharmacologic reduction of lipotoxic ceramide prevents alcoholic steatosis and glucose intolerance in mice, but potential off-target effects limit its strategic utility. Here, we employed a hepatic-specific acid ceramidase (ASAH) overexpression model to reduce hepatic ceramides in a Lieber-DeCarli model of experimental alcoholic steatosis. We examined effects of alcohol on hepatic lipid metabolism, body composition, energy homeostasis, and insulin sensitivity as measured by hyperinsulinemic-euglycemic clamp. Our results demonstrate that hepatic ceramide reduction ameliorates the effects of alcohol on hepatic lipid droplet (LD) accumulation by promoting VLDL secretion and lipophagy, the latter of which involves ceramide cross-talk between the lysosomal and LD compartments. We additionally demonstrate that hepatic ceramide reduction prevents alcohol's inhibition of hepatic insulin signaling. These effects on the liver are associated with a reduction in oxidative stress markers and are relevant to humans, as we observe peri- LD ASAH expression in human ALD. Together, our results suggest a potential role for hepatic ceramide inhibition in preventing ALD.


Assuntos
Ceramidas/metabolismo , Etanol/efeitos adversos , Fígado Gorduroso/metabolismo , Resistência à Insulina , Fígado/efeitos dos fármacos , Fígado/metabolismo , Animais , Composição Corporal , Homeostase/efeitos dos fármacos , Camundongos , Especificidade de Órgãos , Estresse Oxidativo/efeitos dos fármacos
12.
FASEB J ; 32(1): 130-142, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28864659

RESUMO

Perilipin 2 (PLIN2) is a lipid-droplet protein that is up-regulated in alcoholic steatosis and associated with hepatic accumulation of ceramides, bioactive lipids implicated in alcoholic liver disease pathogenesis. The specific role of ceramide synthetic enzymes in the regulation of PLIN2 and promotion of hepatocellular lipid accumulation is not well understood. We examined the effects of pharmacologic ceramide synthesis inhibition on hepatic PLIN2 expression, steatosis, and glucose and lipid homeostasis in mice with alcoholic steatosis and in ethanol-incubated human hepatoma VL17A cells. In cells, pharmacologic inhibition of ceramide synthase reduced lipid accumulation by reducing PLIN2 RNA stability. The subtype ceramide synthase (CerS)6 was specifically up-regulated in experimental alcoholic steatosis in vivo and in vitro and was up-regulated in zone 3 hepatocytes in human alcoholic steatosis. In vivo ceramide reduction by inhibition of de novo ceramide synthesis reduced PLIN2 and hepatic steatosis in alcohol-fed mice, but only de novo synthesis inhibition, not sphingomyelin hydrolysis, improved glucose tolerance and dyslipidemia. These findings implicate CerS6 as a novel regulator of PLIN2 and suggest that ceramide synthetic enzymes may promote the earliest stage of alcoholic liver disease, alcoholic steatosis.-Williams, B., Correnti, J., Oranu, A., Lin, A., Scott, V., Annoh, M., Beck, J., Furth, E., Mitchell, V., Senkal, C. E., Obeid, L., Carr, R. M. A novel role for ceramide synthase 6 in mouse and human alcoholic steatosis.


Assuntos
Fígado Gorduroso Alcoólico/enzimologia , Proteínas de Membrana/metabolismo , Esfingosina N-Aciltransferase/metabolismo , Animais , Vias Biossintéticas , Linhagem Celular , Ceramidas/biossíntese , Modelos Animais de Doenças , Etanol , Fígado Gorduroso Alcoólico/etiologia , Fígado Gorduroso Alcoólico/genética , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Perilipina-2/genética , Perilipina-2/metabolismo , Estabilidade de RNA , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Esfingomielina Fosfodiesterase/metabolismo , Esfingosina N-Aciltransferase/antagonistas & inibidores , Esfingosina N-Aciltransferase/genética , Regulação para Cima/efeitos dos fármacos
13.
Am J Transplant ; 18(3): 745-749, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29116687

RESUMO

Erythropoietic protoporphyria (EPP) is a rare inherited disorder of the heme biosynthesis pathway resulting in the accumulation of protoporphyrins in the blood, erythrocytes, and other tissues. Because of a gene mutation in the FECH gene, ferrochelatase, the enzyme involved in the final step of heme synthesis, is deficient in these patients. Although the major symptom of this disorder is photosensitivity, rarely, it can cause progressive liver disease requiring liver transplantation (LT). However, LT is not curative and only bone marrow transplantation (BMT) can correct the underlying enzymatic defect. Because liver disease results from accumulation of protoporphyrin in the liver, LT without hematopoietic stem cell transplantation leaves the new liver at risk for similar EPP-related damage. A handful of pediatric patients undergoing sequential LT and stem cell transplantation have been described in the literature; however, to date none has been described in detail in adults. We report a case of an adult male with EPP and liver failure who successfully underwent a sequential liver and hematopoietic stem cell transplantation (HSCT).


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Fígado/métodos , Protoporfiria Eritropoética/terapia , Adulto , Humanos , Masculino , Prognóstico
15.
J Vasc Interv Radiol ; 29(2): 237-243, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29221923

RESUMO

PURPOSE: To examine differences in outcome and response of cirrhotomimetic (CMM) hepatocellular carcinoma (HCC) to a combination of bridging transcatheter arterial chemoembolization and orthotopic liver transplantation (OLT) compared with non-CMM HCC. MATERIALS AND METHODS: All patients with pathologically proven CMM HCC who underwent bridging transcatheter arterial chemoembolization before OLT between 2007 and 2013 (n = 23) were retrospectively compared with a control group of patients with pathologically proven non-CMM HCC (n = 46). RESULTS: There were 29 tumors in the CMM HCC group and 64 tumors in the non-CMM group identified and treated. Objective response rate on MR imaging at 1 and 3 months after transcatheter arterial chemoembolization for CMM HCC tumors (including patients with complete and partial response) was 93.1% and 86.4% compared with 85.2% and 93.2% for non-CMM tumors without statistically significant difference (P = .54 and P = .09, respectively). Pathologic study of liver explants showed complete tumor necrosis in 62.3% of non-CMM tumors (38/61) compared with 10.3% of CMM tumors (3/29) (P < .0001). Overall 2-year survival after transcatheter arterial chemoembolization and OLT was significantly lower for patients with CMM HCC compared with patients non-CMM HCC (65.2% vs 87%, P = .03). Patients with CMM HCC with extranodular tumor extension involving > 50% of liver parenchyma had worse survival with mean 2-year survival of 402 days ± 102 vs 656 days ± 39 for the remaining patients with CMM HCC (P = .02). CONCLUSIONS: Despite similar early imaging response rates, CMM HCC tumors had markedly lower rates of complete pathologic necrosis on liver explants and were associated with reduced survival after OLT compared with conventional HCCs.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Transplante de Fígado , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Resultado do Tratamento
16.
Radiology ; 283(3): 702-710, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28253108

RESUMO

Purpose To characterize hepatocellular carcinoma (HCC) cells surviving ischemia with respect to cell cycle kinetics, chemosensitivity, and molecular dependencies that may be exploited to potentiate treatment with transarterial embolization (TAE). Materials and Methods Animal studies were performed according to institutionally approved protocols. The growth kinetics of HCC cells were studied in standard and ischemic conditions. Viability and cell cycle kinetics were measured by using flow cytometry. Cytotoxicity profiling was performed by using a colorimetric cell proliferation assay. Analyses of the Cancer Genome Atlas HCC RNA-sequencing data were performed by using Ingenuity Pathway Analysis software. Activation of molecular mediators of autophagy was measured with Western blot analysis and fluorescence microscopy. In vivo TAE was performed in a rat model of HCC with (n = 5) and without (n = 5) the autophagy inhibitor Lys05. Statistical analyses were performed by using GraphPad software. Results HCC cells survived ischemia with an up to 43% increase in the fraction of quiescent cells as compared with cells grown in standard conditions (P < .004). Neither doxorubicin nor mitomycin C potentiated the cytotoxic effects of ischemia. Gene-set analysis revealed an increase in mRNA expression of the mediators of autophagy (eg, CDKN2A, PPP2R2C, and TRAF2) in HCC as compared with normal liver. Cells surviving ischemia were autophagy dependent. Combination therapy coupling autophagy inhibition and TAE in a rat model of HCC resulted in a 21% increase in tumor necrosis compared with TAE alone (P = .044). Conclusion Ischemia induces quiescence in surviving HCC cells, resulting in a dependence on autophagy, providing a potential therapeutic target for combination therapy with TAE. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Autofagia , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Neoplasias Hepáticas Experimentais/patologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Embolização Terapêutica , Ratos , Ratos Wistar
17.
J Vasc Interv Radiol ; 28(7): 1043-1050.e2, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28495453

RESUMO

PURPOSE: To test the hypotheses that (i) heavier rats demonstrate improved survival with diminished fibrosis in a diethylnitrosamine (DEN)-induced model of hepatocellular carcinoma (HCC) and (ii) transarterial embolization via femoral artery access decreases procedure times versus carotid access. MATERIALS AND METHODS: One hundred thirty-eight male Wistar rats ingested 0.01% DEN in water ad libitum for 12 weeks. T2-weighted magnetic resonance imaging was used for tumor surveillance. Rats underwent selective embolization of ≥ 5 mm tumors via carotid or femoral artery catheterization under fluoroscopic guidance. Rats were retrospectively categorized into 3 groups by initial weight (< 300, 300-400, > 400 g) for analyses of survival, tumor latency, and fibrosis. Access site was compared relative to procedural success, mortality, and time. RESULTS: No significant differences in tumor latency were related to weight group (P = .310). Rats weighing < 300 g had shorter survival than both heavier groups (mean, 88 vs 108 d; P < .0001), and more severe fibrosis (< 300 g median, 4.0; 300-400 g median, 1.5; > 400 g median, 1.0; P = .015). No significant difference was found in periprocedural mortality based on access site; however, procedure times were shorter via femoral approach (mean, 71 ± 23 vs 127 ± 24 min; P < .0001). CONCLUSIONS: Greater initial body weight resulted in improved survival without prolonged tumor latency for rats with DEN-induced HCCs and was associated with less severe fibrosis. A femoral approach for embolization resulted in decreased procedure time. These modifications provide a translational animal model of HCC and transarterial embolization that may be suited for short-term survival studies.


Assuntos
Peso Corporal , Carcinoma Hepatocelular/terapia , Embolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Animais , Dietilnitrosamina , Modelos Animais de Doenças , Fibrose , Fluoroscopia , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Wistar , Estudos Retrospectivos , Taxa de Sobrevida
18.
AJR Am J Roentgenol ; 208(1): 101-106, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27726411

RESUMO

OBJECTIVE: The purpose of this study is to present the clinical and radiographic findings of esophageal lichen planus. MATERIALS AND METHODS: A search of computerized medical records identified 15 patients with pathologic findings of esophageal lichen planus on endoscopic biopsy specimens. Three other patients had presumed esophageal lichen planus, although no biopsy specimens were obtained. Twelve of these 18 patients (67%) had double-contrast esophagography performed at our institution; for eight of the 12 patients (67%), the studies revealed abnormalities in the esophagus. These eight patients constituted our study group. The barium esophagrams and medical records of these eight patients were reviewed to determine the clinical, radiographic, and endoscopic findings of esophageal lichen planus as well as the treatment and patient outcome. RESULTS: All eight patients were women (median age, 66.5 years), and all eight presented with dysphagia (mean duration, 3.2 years). Four patients had previous lichen planus that involved the skin (n = 1), the oral cavity (n = 2), or both (n = 1), and one patient later had lichen planus that involved the vagina. Five patients had a small-caliber esophagus with diffuse esophageal narrowing. The remaining three patients had segmental strictures in the cervical (n = 1), upper thoracic (n = 1), and distal thoracic (n = 1) esophagus. CONCLUSION: Esophageal lichen planus typically occurs in older women with longstanding dysphagia and often develops in the absence of extraesophageal disease. Barium esophagrams may reveal a small-caliber esophagus or, less commonly, segmental esophageal strictures. Greater awareness of the radiographic findings of esophageal lichen planus hopefully will lead to earlier diagnosis and better management of this condition.


Assuntos
Doenças do Esôfago/diagnóstico por imagem , Doenças do Esôfago/patologia , Líquen Plano/diagnóstico por imagem , Líquen Plano/patologia , Tomografia Computadorizada por Raios X/métodos , Idoso , Diagnóstico Diferencial , Esôfago/diagnóstico por imagem , Esôfago/patologia , Humanos , Masculino
19.
Int J Cancer ; 139(7): 1546-56, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27194209

RESUMO

Cancer somatic genetic evolution is a direct contributor to heterogeneity at the clonal and molecular level in colorectal adenocarcinoma (COAD). We sought to determine the extent to which genetic evolution may be detected in COAD in routinely obtained single clinical specimens and establish clinical significance with regard to clinicopathologic and outcome data. One hundred and twenty three cases of routinely collected mismatch repair proficient COAD were sequenced on the Illumina Truseq Amplicon assay. Measures of intratumoral heterogeneity and the preferential timing of mutational events were assessed and compared to clinicopathologic data. Survival subanalysis was performed on 55 patients. Patient age (p = 0.013) and specimen percent tumor (p = 0.033) was associated with clonal diversity, and biopsy (p = 0.044) and metastasis (p = 0.044) returned fewer mutations per case. APC and TP53 mutations preferentially occurred early while alterations in FBXW7, FLT3, SMAD4, GNAS and PTEN preferentially occurred as late events. Temporal heterogeneity was evident in KRAS and PIK3CA mutations. Hierarchical clustering revealed a TP53 mutant subtype and a MAPK-PIK3CA subtype with differing patterns of late mutational events. Survival subanalysis showed a decreased median progression free survival for the MAPK-PIK3CA subtype (8 months vs. 13 months; univariate logrank p = 0.0380, cox model p= 0.018). Neoadjuvant therapy associated mutations were found for ERBB2 (p = 0.0481) and FBXW7 (p = 0.015). Our data indicate novel molecular subtypes of mismatch repair proficient COAD display differing patterns of genetic evolution which correlate with clinical outcomes. Furthermore, we report treatment acquired and/or selected mutations in ERBB2 and FBXW7.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA , Proteínas de Ciclo Celular/genética , Análise por Conglomerados , Evolução Molecular , Proteínas F-Box/genética , Proteína 7 com Repetições F-Box-WD , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/genética , Ubiquitina-Proteína Ligases/genética
20.
Ann Surg ; 263(4): 793-801, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26135696

RESUMO

BACKGROUND: Early invasive carcinoma may be encountered in association with intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. The natural history of these early invasive lesions is unknown. METHODS: Pancreatic surgical databases from 4 high-volume centers were queried for IPMNs, with invasive components measuring 20 mm or less. All cases were reviewed by GI gastrointestinal pathologists, and pathologic features were analyzed to identify predictors of recurrence and survival. RESULTS: A total of 70 small IPMN-associated invasive carcinomas (≤20-mm invasion) were identified, comprising 25% of resected IPMN-associated carcinomas (n = 280). Most of these small invasive cancers were multifocal (66%), less than 10 mm in size (73%), and arose in the setting of a main duct IPMN (96%). The most common adenocarcinoma subtypes were tubular (57%) and colloid (29%). Lymph node metastases were present in 19% of cases and 23% were T3 lesions. The overall recurrence rate was 24% (n = 17), and the median time to recurrence was 16 months (range: 4-132 months). Median and 5-year survival rates were 99 months and 59%. Recurrence patterns of invasive disease were local in 35%, distant in 47%, and both in 18%. Lymphatic spread and T3 stage were predictive of recurrence (univariate, P = 0.006), whereas tubular carcinoma type was the most predictive of poor overall survival (multivariate hazard ratio = 3.7, P = 0.04). CONCLUSIONS: This study represents the largest multi-institutional experience of resected small IPMN-associated carcinoma. Although these malignancies may frequently be cured with resection, recurrence risk is significant. Lymphatic spread, increased T stage, and tubular type carcinoma were associated with the poorest outcome.


Assuntos
Carcinoma Ductal Pancreático/cirurgia , Recidiva Local de Neoplasia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Carga Tumoral
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