Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 231
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 186(9): 1968-1984.e20, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37040760

RESUMO

Somatic mutations in nonmalignant tissues accumulate with age and injury, but whether these mutations are adaptive on the cellular or organismal levels is unclear. To interrogate genes in human metabolic disease, we performed lineage tracing in mice harboring somatic mosaicism subjected to nonalcoholic steatohepatitis (NASH). Proof-of-concept studies with mosaic loss of Mboat7, a membrane lipid acyltransferase, showed that increased steatosis accelerated clonal disappearance. Next, we induced pooled mosaicism in 63 known NASH genes, allowing us to trace mutant clones side by side. This in vivo tracing platform, which we coined MOSAICS, selected for mutations that ameliorate lipotoxicity, including mutant genes identified in human NASH. To prioritize new genes, additional screening of 472 candidates identified 23 somatic perturbations that promoted clonal expansion. In validation studies, liver-wide deletion of Tbx3, Bcl6, or Smyd2 resulted in protection against hepatic steatosis. Selection for clonal fitness in mouse and human livers identifies pathways that regulate metabolic disease.


Assuntos
Doenças Metabólicas , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Masculino , Camundongos , Histona-Lisina N-Metiltransferase/genética , Fígado/metabolismo , Mosaicismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
2.
Cell ; 174(5): 1200-1215.e20, 2018 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-30100187

RESUMO

Nuclear pore complexes (NPCs) regulate nuclear-cytoplasmic transport, transcription, and genome integrity in eukaryotic cells. However, their functional roles in cancer remain poorly understood. We interrogated the evolutionary transcriptomic landscape of NPC components, nucleoporins (Nups), from primary to advanced metastatic human prostate cancer (PC). Focused loss-of-function genetic screen of top-upregulated Nups in aggressive PC models identified POM121 as a key contributor to PC aggressiveness. Mechanistically, POM121 promoted PC progression by enhancing importin-dependent nuclear transport of key oncogenic (E2F1, MYC) and PC-specific (AR-GATA2) transcription factors, uncovering a pharmacologically targetable axis that, when inhibited, decreased tumor growth, restored standard therapy efficacy, and improved survival in patient-derived pre-clinical models. Our studies molecularly establish a role of NPCs in PC progression and give a rationale for NPC-regulated nuclear import targeting as a therapeutic strategy for lethal PC. These findings may have implications for understanding how NPC deregulation contributes to the pathogenesis of other tumor types.


Assuntos
Fator de Transcrição E2F1/metabolismo , Glicoproteínas de Membrana/metabolismo , Poro Nuclear/fisiologia , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular , Carcinogênese , Núcleo Celular/metabolismo , Proliferação de Células , Fator de Transcrição GATA2/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Membrana Nuclear , Complexo de Proteínas Formadoras de Poros Nucleares , Transdução de Sinais
3.
Immunity ; 56(1): 58-77.e11, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36521495

RESUMO

Obesity-induced chronic liver inflammation is a hallmark of nonalcoholic steatohepatitis (NASH)-an aggressive form of nonalcoholic fatty liver disease. However, it remains unclear how such a low-grade, yet persistent, inflammation is sustained in the liver. Here, we show that the macrophage phagocytic receptor TREM2, induced by hepatocyte-derived sphingosine-1-phosphate, was required for efferocytosis of lipid-laden apoptotic hepatocytes and thereby maintained liver immune homeostasis. However, prolonged hypernutrition led to the production of proinflammatory cytokines TNF and IL-1ß in the liver to induce TREM2 shedding through ADAM17-dependent proteolytic cleavage. Loss of TREM2 resulted in aberrant accumulation of dying hepatocytes, thereby further augmenting proinflammatory cytokine production. This ultimately precipitated a vicious cycle that licensed chronic inflammation to drive simple steatosis transition to NASH. Therefore, impaired macrophage efferocytosis is a previously unrecognized key pathogenic event that enables chronic liver inflammation in obesity. Blocking TREM2 cleavage to restore efferocytosis may represent an effective strategy to treat NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Hipernutrição , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hipernutrição/patologia , Fígado/patologia , Inflamação/patologia , Obesidade/patologia , Glicoproteínas de Membrana , Receptores Imunológicos
4.
Nature ; 610(7931): 356-365, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198802

RESUMO

Hepatocellular carcinoma (HCC), the fourth leading cause of cancer mortality worldwide, develops almost exclusively in patients with chronic liver disease and advanced fibrosis1,2. Here we interrogated functions of hepatic stellate cells (HSCs), the main source of liver fibroblasts3, during hepatocarcinogenesis. Genetic depletion, activation or inhibition of HSCs in mouse models of HCC revealed their overall tumour-promoting role. HSCs were enriched in the preneoplastic environment, where they closely interacted with hepatocytes and modulated hepatocarcinogenesis by regulating hepatocyte proliferation and death. Analyses of mouse and human HSC subpopulations by single-cell RNA sequencing together with genetic ablation of subpopulation-enriched mediators revealed dual functions of HSCs in hepatocarcinogenesis. Hepatocyte growth factor, enriched in quiescent and cytokine-producing HSCs, protected against hepatocyte death and HCC development. By contrast, type I collagen, enriched in activated myofibroblastic HSCs, promoted proliferation and tumour development through increased stiffness and TAZ activation in pretumoural hepatocytes and through activation of discoidin domain receptor 1 in established tumours. An increased HSC imbalance between cytokine-producing HSCs and myofibroblastic HSCs during liver disease progression was associated with increased HCC risk in patients. In summary, the dynamic shift in HSC subpopulations and their mediators during chronic liver disease is associated with a switch from HCC protection to HCC promotion.


Assuntos
Carcinogênese , Carcinoma Hepatocelular , Células Estreladas do Fígado , Neoplasias Hepáticas , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Proliferação de Células , Colágeno Tipo I/metabolismo , Receptor com Domínio Discoidina 1/metabolismo , Progressão da Doença , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/patologia , Camundongos , Miofibroblastos/patologia
5.
Nat Immunol ; 16(12): 1235-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26502405

RESUMO

Ectopic lymphoid-like structures (ELSs) are often observed in cancer, yet their function is obscure. Although ELSs signify good prognosis in certain malignancies, we found that hepatic ELSs indicated poor prognosis for hepatocellular carcinoma (HCC). We studied an HCC mouse model that displayed abundant ELSs and found that they constituted immunopathological microniches wherein malignant hepatocyte progenitor cells appeared and thrived in a complex cellular and cytokine milieu until gaining self-sufficiency. The egress of progenitor cells and tumor formation were associated with the autocrine production of cytokines previously provided by the niche. ELSs developed via cooperation between the innate immune system and adaptive immune system, an event facilitated by activation of the transcription factor NF-κB and abolished by depletion of T cells. Such aberrant immunological foci might represent new targets for cancer therapy.


Assuntos
Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Tecido Linfoide/imunologia , Células-Tronco Neoplásicas/imunologia , Nicho de Células-Tronco/imunologia , Imunidade Adaptativa/genética , Imunidade Adaptativa/imunologia , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Hibridização Genômica Comparativa , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Hepatócitos/imunologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Quinase I-kappa B/metabolismo , Imunidade Inata/genética , Imunidade Inata/imunologia , Immunoblotting , Hibridização In Situ , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/imunologia , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nicho de Células-Tronco/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma/genética , Transcriptoma/imunologia
6.
Am J Pathol ; 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39103092

RESUMO

Cholangiocarcinomas (CCAs) are a heterogeneous group of malignant tumors that originate from the biliary tract. They are usually diagnosed in advanced stages, leading to a dismal prognosis for affected patients. As CCA often arises as a sporadic cancer in individuals lacking specific risk factors or with heterogeneous backgrounds, and there are no defined high-risk groups, the implementation of effective surveillance programs for CCA is problematic. The identification and validation of new biomarkers useful for risk stratification, diagnosis, prognosis, and prediction of treatment response remains an unmet need for patients with CCA, even though numerous studies have been conducted lately to try to discover and validate CCA biomarkers. In this review, we overview the available information about the different types of biomarkers that have been investigated in recent years using minimally invasive biospecimens (blood, serum/plasma, bile, and urine) and their potential usefulness in diagnosis, prognosis, and risk stratification. It is widely accepted that early detection of CCA will impact patients' outcomes, by improving survival rates, quality of life, and the possibility of less invasive and/or curative treatments; however, challenges to its translation and clinical application for patients with CCA need to be resolved.

7.
J Proteome Res ; 23(9): 3791-3805, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-38980715

RESUMO

Hepatocellular carcinoma (HCC) mortality rates continue to increase faster than those of other cancer types due to high heterogeneity, which limits diagnosis and treatment. Pathological and molecular subtyping have identified that HCC tumors with poor outcomes are characterized by intratumoral collagenous accumulation. However, the translational and post-translational regulation of tumor collagen, which is critical to the outcome, remains largely unknown. Here, we investigate the spatial extracellular proteome to understand the differences associated with HCC tumors defined by Hoshida transcriptomic subtypes of poor outcome (Subtype 1; S1; n = 12) and better outcome (Subtype 3; S3; n = 24) that show differential stroma-regulated pathways. Collagen-targeted mass spectrometry imaging (MSI) with the same-tissue reference libraries, built from untargeted and targeted LC-MS/MS was used to spatially define the extracellular microenvironment from clinically-characterized, formalin-fixed, paraffin-embedded tissue sections. Collagen α-1(I) chain domains for discoidin-domain receptor and integrin binding showed distinctive spatial distribution within the tumor microenvironment. Hydroxylated proline (HYP)-containing peptides from the triple helical regions of fibrillar collagens distinguished S1 from S3 tumors. Exploratory machine learning on multiple peptides extracted from the tumor regions could distinguish S1 and S3 tumors (with an area under the receiver operating curve of ≥0.98; 95% confidence intervals between 0.976 and 1.00; and accuracies above 94%). An overall finding was that the extracellular microenvironment has a high potential to predict clinically relevant outcomes in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteômica , Microambiente Tumoral , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/classificação , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/classificação , Humanos , Proteômica/métodos , Espectrometria de Massas em Tandem , Proteoma/análise , Proteoma/genética , Cromatografia Líquida , Aprendizado de Máquina , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética
8.
Trends Genet ; 37(5): 403-404, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33541711

RESUMO

Despite several technical challenges, human induced pluripotent stem cell (hiPSC)-derived organoids enable biologically and clinically relevant functional study of physiology and disease. In a recent Cell Systems article, Velazquez et al. report a novel strategy to identify regulators of multilineage organoid maturation by reverse-engineering from the global transcriptome of human tissues.


Assuntos
Células-Tronco Pluripotentes Induzidas , Organoides , Humanos , Fígado , Transcriptoma
9.
Gastroenterology ; 164(7): 1279-1292, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36894036

RESUMO

BACKGROUND & AIMS: Despite recent progress, long-term survival remains low for hepatocellular carcinoma (HCC). The most effective HCC therapies target the tumor immune microenvironment (TIME), and there are almost no therapies that directly target tumor cells. Here, we investigated the regulation and function of tumor cell-expressed Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) in HCC. METHODS: HCC was induced in mice by Sleeping Beauty-mediated expression of MET, CTNNB1-S45Y, or TAZ-S89A, or by diethylnitrosamine plus CCl4. Hepatocellular TAZ and YAP were deleted in floxed mice via adeno-associated virus serotype 8-mediated expression of Cre. TAZ target genes were identified from RNA sequencing, confirmed by chromatin immunoprecipitation, and evaluated in a clustered regularly interspaced short palindromic repeats interference (CRISPRi) screen. TEA domain transcription factors (TEADs), anillin (ANLN), Kif23, and programmed cell death protein ligand 1 were knocked down by guide RNAs in dead clustered regularly interspaced short palindromic repeats-associated protein 9 (dCas9) knock-in mice. RESULTS: YAP and TAZ were up-regulated in murine and human HCC, but only deletion of TAZ consistently decreased HCC growth and mortality. Conversely, overexpression of activated TAZ was sufficient to trigger HCC. TAZ expression in HCC was regulated by cholesterol synthesis, as demonstrated by pharmacologic or genetic inhibition of 3-hydroxy-3-methylglutaryl- coenzyme A reductase (HMGCR), farnesyl pyrophosphate synthase, farnesyl-diphosphate farnesyltransferase 1 (FDFT1), or sterol regulatory element-binding protein 2 (SREBP2). TAZ- and MET/CTNNB1-S45Y-driven HCC required the expression of TEAD2 and, to a lesser extent, TEAD4. Accordingly, TEAD2 displayed the most profound effect on survival in patients with HCC. TAZ and TEAD2 promoted HCC via increased tumor cell proliferation, mediated by TAZ target genes ANLN and kinesin family member 23 (KIF23). Therapeutic targeting of HCC, using pan-TEAD inhibitors or the combination of a statin with sorafenib or anti-programmed cell death protein 1, decreased tumor growth. CONCLUSIONS: Our results suggest the cholesterol-TAZ-TEAD2-ANLN/KIF23 pathway as a mediator of HCC proliferation and tumor cell-intrinsic therapeutic target that could be synergistically combined with TIME-targeted therapies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Proteínas de Sinalização YAP/metabolismo
10.
Hepatology ; 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37300379

RESUMO

Liver cancer, primarily HCC, exhibits highly heterogeneous histological and molecular aberrations across tumors and within individual tumor nodules. Such intertumor and intratumor heterogeneities may lead to diversity in the natural history of disease progression and various clinical disparities across the patients. Recently developed multimodality, single-cell, and spatial omics profiling technologies have enabled interrogation of the intertumor/intratumor heterogeneity in the cancer cells and the tumor immune microenvironment. These features may influence the natural history and efficacy of emerging therapies targeting novel molecular and immune pathways, some of which had been deemed undruggable. Thus, comprehensive characterization of the heterogeneities at various levels may facilitate the discovery of biomarkers that enable personalized and rational treatment decisions, and optimize treatment efficacy while minimizing the risk of adverse effects. Such companion biomarkers will also refine HCC treatment algorithms across disease stages for cost-effective patient management by optimizing the allocation of limited medical resources. Despite this promise, the complexity of the intertumor/intratumor heterogeneity and ever-expanding inventory of therapeutic agents and regimens have made clinical evaluation and translation of biomarkers increasingly challenging. To address this issue, novel clinical trial designs have been proposed and incorporated into recent studies. In this review, we discuss the latest findings in the molecular and immune landscape of HCC for their potential and utility as biomarkers, the framework of evaluation and clinical application of predictive/prognostic biomarkers, and ongoing biomarker-guided therapeutic clinical trials. These new developments may revolutionize patient care and substantially impact the still dismal HCC mortality.

11.
Hepatology ; 78(1): 319-362, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36082510

RESUMO

Hepatocellular carcinoma (HCC) mortality remains high primarily due to late diagnosis as a consequence of failed early detection. Professional societies recommend semi-annual HCC screening in at-risk patients with chronic liver disease to increase the likelihood of curative treatment receipt and improve survival. However, recent dynamic shift of HCC etiologies from viral to metabolic liver diseases has significantly increased the potential target population for the screening, whereas annual incidence rate has become substantially lower. Thus, with the contemporary HCC etiologies, the traditional screening approach might not be practical and cost-effective. HCC screening consists of (i) definition of rational at-risk population, and subsequent (ii) repeated application of early detection tests to the population at regular intervals. The suboptimal performance of the currently available HCC screening tests highlights an urgent need for new modalities and strategies to improve early HCC detection. In this review, we overview recent developments of clinical, molecular, and imaging-based tools to address the current challenge, and discuss conceptual framework and approaches of their clinical translation and implementation. These encouraging progresses are expected to transform the current "one-size-fits-all" HCC screening into individualized precision approaches to early HCC detection and ultimately improve the poor HCC prognosis in the foreseeable future.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Biomarcadores , Detecção Precoce de Câncer , Medição de Risco
12.
JAMA ; 331(11): 920-929, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502074

RESUMO

Importance: Aspirin may reduce severity of metabolic dysfunction-associated steatotic liver disease (MASLD) and lower the incidence of end-stage liver disease and hepatocellular carcinoma, in patients with MASLD. However, the effect of aspirin on MASLD is unknown. Objective: To test whether low-dose aspirin reduces liver fat content, compared with placebo, in adults with MASLD. Design, Setting, and Participants: This 6-month, phase 2, randomized, double-blind, placebo-controlled clinical trial was conducted at a single hospital in Boston, Massachusetts. Participants were aged 18 to 70 years with established MASLD without cirrhosis. Enrollment occurred between August 20, 2019, and July 19, 2022, with final follow-up on February 23, 2023. Interventions: Participants were randomized (1:1) to receive either once-daily aspirin, 81 mg (n = 40) or identical placebo pills (n = 40) for 6 months. Main Outcomes and Measures: The primary end point was mean absolute change in hepatic fat content, measured by proton magnetic resonance spectroscopy (MRS) at 6-month follow-up. The 4 key secondary outcomes included mean percentage change in hepatic fat content by MRS, the proportion achieving at least 30% reduction in hepatic fat, and the mean absolute and relative reductions in hepatic fat content, measured by magnetic resonance imaging proton density fat fraction (MRI-PDFF). Analyses adjusted for the baseline value of the corresponding outcome. Minimal clinically important differences for study outcomes were not prespecified. Results: Among 80 randomized participants (mean age, 48 years; 44 [55%] women; mean hepatic fat content, 35% [indicating moderate steatosis]), 71 (89%) completed 6-month follow-up. The mean absolute change in hepatic fat content by MRS was -6.6% with aspirin vs 3.6% with placebo (difference, -10.2% [95% CI, -27.7% to -2.6%]; P = .009). Compared with placebo, aspirin treatment significantly reduced relative hepatic fat content (-8.8 vs 30.0 percentage points; mean difference, -38.8 percentage points [95% CI, -66.7 to -10.8]; P = .007), increased the proportion of patients with 30% or greater relative reduction in hepatic fat (42.5% vs 12.5%; mean difference, 30.0% [95% CI, 11.6% to 48.4%]; P = .006), reduced absolute hepatic fat content by MRI-PDFF (-2.7% vs 0.9%; mean difference, -3.7% [95% CI, -6.1% to -1.2%]; P = .004]), and reduced relative hepatic fat content by MRI-PDFF (-11.7 vs 15.7 percentage points; mean difference, -27.3 percentage points [95% CI, -45.2 to -9.4]; P = .003). Thirteen participants (32.5%) in each group experienced an adverse event, most commonly upper respiratory tract infections (10.0% in each group) or arthralgias (5.0% for aspirin vs 7.5% for placebo). One participant randomized to aspirin (2.5%) experienced drug-related heartburn. Conclusions and Relevance: In this preliminary randomized clinical trial of patients with MASLD, 6 months of daily low-dose aspirin significantly reduced hepatic fat quantity compared with placebo. Further study in a larger sample size is necessary to confirm these findings. Trial Registration: ClinicalTrials.gov Identifier: NCT04031729.


Assuntos
Anti-Inflamatórios , Aspirina , Fígado Gorduroso , Fígado , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Aspirina/efeitos adversos , Aspirina/farmacologia , Aspirina/uso terapêutico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Método Duplo-Cego , Doença Hepática Terminal/etiologia , Doença Hepática Terminal/prevenção & controle , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Seguimentos , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Cirrose Hepática , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle , Espectroscopia de Prótons por Ressonância Magnética
13.
Genes Dev ; 30(7): 786-97, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27013235

RESUMO

The Hippo signaling pathway is a major regulator of organ size. In the liver, Hippo pathway deregulation promotes hyperplasia and hepatocellular carcinoma primarily through hyperactivation of its downstream effector, YAP. The LATS2 tumor suppressor is a core member of the Hippo pathway. A screen for LATS2-interacting proteins in liver-derived cells identified the transcription factor SREBP2, master regulator of cholesterol homeostasis. LATS2 down-regulation caused SREBP activation and accumulation of excessive cholesterol. Likewise, mice harboring liver-specific Lats2 conditional knockout (Lats2-CKO) displayed constitutive SREBP activation and overexpressed SREBP target genes and developed spontaneous fatty liver disease. Interestingly, the impact of LATS2 depletion on SREBP-mediated transcription was clearly distinct from that of YAP overexpression. When challenged with excess dietary cholesterol, Lats2-CKO mice manifested more severe liver damage than wild-type mice. Surprisingly, apoptosis, inflammation, and fibrosis were actually attenuated relative to wild-type mice, in association with impaired p53 activation. Subsequently, Lats2-CKO mice failed to recover effectively from cholesterol-induced damage upon return to a normal diet. Additionally, decreased LATS2 mRNA in association with increased SREBP target gene expression was observed in a subset of human nonalcoholic fatty liver disease cases. Together, these findings further highlight the tight links between tumor suppressors and metabolic homeostasis.


Assuntos
Fígado Gorduroso/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Colesterol na Dieta/farmacologia , Fígado Gorduroso/genética , Deleção de Genes , Regulação da Expressão Gênica/genética , Células Hep G2 , Homeostase/genética , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Camundongos Knockout , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética
14.
J Hepatol ; 79(1): 226-239, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36854345

RESUMO

Major research efforts in liver cancer have been devoted to increasing the efficacy and effectiveness of surveillance for hepatocellular carcinoma (HCC). As with other cancers, surveillance programmes aim to detect tumours at an early stage, facilitate curative-intent treatment, and reduce cancer-related mortality. HCC surveillance is supported by a large randomised-controlled trial in patients with chronic HBV infection and several cohort studies in cirrhosis; however, effectiveness in clinical practice is limited by several barriers, including inadequate risk stratification, underuse of surveillance, and suboptimal accuracy of screening tests. There are several proposed strategies to address these limitations, including risk stratification algorithms and biomarkers to better identity at-risk individuals, interventions to increase surveillance, and emerging imaging- and blood-based surveillance tests with improved sensitivity and specificity for early HCC detection. Beyond clinical validation, data are needed to establish clinical utility, i.e. increased early tumour detection and reduced HCC-related mortality. If successful, these data could facilitate a precision screening paradigm in which surveillance strategies are tailored to individual HCC risk to maximise overall surveillance value. However, practical and logistical considerations must be considered when designing and implementing these validation efforts. To address these issues, ILCA (the International Liver Cancer Association) adjourned a single topic workshop on HCC risk stratification and surveillance in June 2022. Herein, we present a white paper on these topics, including the status of the field, ongoing research efforts, and barriers to the translation of emerging strategies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/epidemiologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/epidemiologia , Detecção Precoce de Câncer , Cirrose Hepática , Medição de Risco
15.
J Hepatol ; 78(2): 343-355, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36309131

RESUMO

BACKGROUND & AIMS: Despite recent approvals, the response to treatment and prognosis of patients with advanced hepatocellular carcinoma (HCC) remain poor. Claudin-1 (CLDN1) is a membrane protein that is expressed at tight junctions, but it can also be exposed non-junctionally, such as on the basolateral membrane of the human hepatocyte. While CLDN1 within tight junctions is well characterized, the role of non-junctional CLDN1 and its role as a therapeutic target in HCC remains unexplored. METHODS: Using humanized monoclonal antibodies (mAbs) specifically targeting the extracellular loop of human non-junctional CLDN1 and a large series of patient-derived cell-based and animal model systems we aimed to investigate the role of CLDN1 as a therapeutic target for HCC. RESULTS: Targeting non-junctional CLDN1 markedly suppressed tumor growth and invasion in cell line-based models of HCC and patient-derived 3D ex vivo models. Moreover, the robust effect on tumor growth was confirmed in vivo in a large series of cell line-derived xenograft and patient-derived xenograft mouse models. Mechanistic studies, including single-cell RNA sequencing of multicellular patient HCC tumorspheres, suggested that CLDN1 regulates tumor stemness, metabolism, oncogenic signaling and perturbs the tumor immune microenvironment. CONCLUSIONS: Our results provide the rationale for targeting CLDN1 in HCC and pave the way for the clinical development of CLDN1-specific mAbs for the treatment of advanced HCC. IMPACT AND IMPLICATIONS: Hepatocellular carcinoma (HCC) is associated with high mortality and unsatisfactory treatment options. Herein, we identified the cell surface protein Claudin-1 as a treatment target for advanced HCC. Monoclonal antibodies targeting Claudin-1 inhibit tumor growth in patient-derived ex vivo and in vivo models by modulating signaling, cell stemness and the tumor immune microenvironment. Given the differentiated mechanism of action, the identification of Claudin-1 as a novel therapeutic target for HCC provides an opportunity to break the plateau of limited treatment response. The results of this preclinical study pave the way for the clinical development of Claudin-1-specific antibodies for the treatment of advanced HCC. It is therefore of key impact for physicians, scientists and drug developers in the field of liver cancer and gastrointestinal oncology.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/genética , Claudina-1/genética , Neoplasias Hepáticas/genética , Carcinógenos , Microambiente Tumoral , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Linhagem Celular Tumoral
16.
Gut ; 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36591611

RESUMO

OBJECTIVES: Chronic hepatitis B virus (HBV) infection is a leading cause of liver disease and hepatocellular carcinoma. A key feature of HBV replication is the synthesis of the covalently close circular (ccc)DNA, not targeted by current treatments and whose elimination would be crucial for viral cure. To date, little is known about cccDNA formation. One major challenge to address this urgent question is the absence of robust models for the study of cccDNA biology. DESIGN: We established a cell-based HBV cccDNA reporter assay and performed a loss-of-function screen targeting 239 genes encoding the human DNA damage response machinery. RESULTS: Overcoming the limitations of current models, the reporter assay enables to quantity cccDNA levels using a robust ELISA as a readout. A loss-of-function screen identified 27 candidate cccDNA host factors, including Y box binding protein 1 (YBX1), a DNA binding protein regulating transcription and translation. Validation studies in authentic infection models revealed a robust decrease in HBV cccDNA levels following silencing, providing proof-of-concept for the importance of YBX1 in the early steps of the HBV life cycle. In patients, YBX1 expression robustly correlates with both HBV load and liver disease progression. CONCLUSION: Our cell-based reporter assay enables the discovery of HBV cccDNA host factors including YBX1 and is suitable for the characterisation of cccDNA-related host factors, antiviral targets and compounds.

17.
Semin Liver Dis ; 42(4): 501-513, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36104114

RESUMO

Liver cancer, mainly hepatocellular carcinoma (HCC), remains a major cause of cancer-related death worldwide. With the global epidemic of obesity, the major HCC etiologies have been dynamically shifting from viral to metabolic liver diseases. This change has made HCC prevention difficult with increasingly elusive at-risk populations as rational target for preventive interventions. Besides ongoing efforts to reduce obesity and metabolic disorders, chemoprevention in patients who already have metabolic liver diseases may have a significant impact on the poor HCC prognosis. Hepatitis B- and hepatitis C-related HCC incidences have been substantially reduced by the new antivirals, but HCC risk can persist over a decade even after successful viral treatment, highlighting the need for HCC-preventive measures also in these patients. Experimental and retrospective studies have suggested potential utility of generic agents such as lipophilic statins and aspirin for HCC chemoprevention given their well-characterized safety profile, although anticipated efficacy may be modest. In this review, we overview recent clinical and translational studies of generic agents in the context of HCC chemoprevention under the contemporary HCC etiologies. We also discuss newly emerging approaches to overcome the challenges in clinical testing of the agents to facilitate their clinical translation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/epidemiologia , Estudos Retrospectivos , Quimioprevenção/efeitos adversos , Antivirais/uso terapêutico , Obesidade/complicações
18.
J Hepatol ; 77(1): 128-139, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35139400

RESUMO

BACKGROUND & AIMS: There is controversy regarding the overall value of hepatocellular carcinoma (HCC) surveillance in patients with cirrhosis given the lack of data from randomized-controlled trials. To address this issue, we conducted a systematic review and meta-analysis of cohort studies evaluating the benefits and harms of HCC surveillance in patients with cirrhosis. METHODS: We performed a search of the Medline and EMBASE databases and national meeting abstracts from January 2014 through July 2020 for studies reporting early-stage HCC detection, curative treatment receipt, or overall survival, stratified by HCC surveillance status, among patients with cirrhosis. Pooled risk ratios (RRs) and hazard ratios, according to HCC surveillance status, were calculated for each outcome using the DerSimonian and Laird method for random effects models. RESULTS: We identified 59 studies including 145,396 patients with HCC, which was detected by surveillance in 41,052 (28.2%) cases. HCC surveillance was associated with improved early-stage detection (RR 1.86, 95% CI 1.73-1.98; I2 = 82%), curative treatment receipt (RR 1.83, 95% CI 1.69-1.97; I2 = 75%), and overall survival (hazard ratio 0.67, 95% CI 0.61-0.72; I2 = 78%) after adjusting for lead-time bias; however, there was notable heterogeneity in all pooled estimates. Four studies examined surveillance-related physical harms due to false positive or indeterminate surveillance results, but no studies examined potential financial or psychological harms. The proportion of patients experiencing surveillance-related physical harms ranged from 8.8% to 27.5% across studies, although most harms were mild in severity. CONCLUSION: HCC surveillance is associated with improved early detection, curative treatment receipt, and survival in patients with cirrhosis, although there was heterogeneity in pooled estimates. Available data suggest HCC surveillance is of high value in patients with cirrhosis, although continued rigorous studies evaluating benefits and harms are still needed. LAY SUMMARY: There has been ongoing debate about the overall value of hepatocellular carcinoma (HCC) screening in patients with cirrhosis given the lack of data from randomized-controlled trials. In a systematic review of contemporary cohort studies, we found that HCC screening is associated with improved early detection, curative treatment receipt, and survival in patients with cirrhosis, although there were fewer data quantifying potential screening-related harms. Available data suggest HCC screening is of high value in patients with cirrhosis, although continued studies evaluating benefits and harms are still needed.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/terapia , Diagnóstico Precoce , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/terapia , Programas de Rastreamento/métodos
19.
Clin Gastroenterol Hepatol ; 20(3): 651-657, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33667676

RESUMO

BACKGROUND & AIMS: Severe alcoholic hepatitis (AH) is a highly lethal condition and it is still a challenge to predict the outcome. We previously identified and validated a composite score of hepatic 123-gene prognostic signature and the model for end-stage liver disease (MELD) score: gene signature-MELD. However, the need for liver biopsy limits its clinical application. Therefore, we aimed to identify a plasma protein-based surrogate of the gene signature and independently validate its prognostic capability. METHODS: All patients were diagnosed with severe AH at Cliniques universitaires de Bruxelles Hôpital Erasme (Brussels, Belgium), and the plasma samples were collected at admission before any treatment. The primary outcome was death or liver transplantation within 90 days. Using our computational pipeline, named translation of tissue expression to secretome (TexSEC), a hepatic-transcriptome-based prognostic signature was converted to a plasma-based secretome signature, which was optimized in 50 patients by comparing their hepatic molecular dysregulation status and combining it with the MELD score. The composite score was validated independently in 57 patients. RESULTS: The TexSEC and optimization process identified a 6-plasma-protein panel as a surrogate for the 123-gene signature. A composite score with the MELD score, the plasma-signature (ps)-MELD score, was created by using the coefficients of the gene signature-MELD equation. In the validation cohort, the high-risk ps-MELD (n = 23; 40%) was associated significantly with death or liver transplantation within 90 days (adjusted hazard ratio, 4.57; 95% CI, 2.15-9.30; P < .001). The ps-MELD score showed a stable, high prognostic association (time-dependent area under receiver operating characteristics curve, >0.80) and was well calibrated over time; it consistently outperformed existing clinical scores as indicated by various model performance indices. CONCLUSIONS: The high-risk ps-MELD score was associated with short-term survival in patients with severe AH.


Assuntos
Doença Hepática Terminal , Hepatite Alcoólica , Hepatite Alcoólica/tratamento farmacológico , Humanos , Testes de Função Hepática , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença
20.
Clin Gastroenterol Hepatol ; 20(5): e1188-e1191, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33727162

RESUMO

Cirrhosis is the terminal stage of progressive liver fibrosis, affecting 1%-2% of the global population and accounting for 1.3 million deaths annually.1,2 Median survival for persons with compensated cirrhosis is approximately 12 years, compared with only 2 years for those with hepatic decompensation. Accurate prediction of hepatic decompensation is an unmet need to enable identification of patients with cirrhosis who could benefit from close monitoring and timely medical interventions. Besides, risk stratification of patients with cirrhosis could help inform patient selection for trials evaluating therapies to prevent hepatic decompensation. Although various clinical scores, such as the albumin-bilirubin (ALBI) and fibrosis-4 (FIB-4) indices (ALBI-FIB4 score) have been proposed to predict long-term risk of hepatic decompensation,3 external validation has often shown suboptimal prognostic capability and revealed room for improvement.4.


Assuntos
Cirrose Hepática , Secretoma , Bilirrubina , Fibrose , Humanos , Cirrose Hepática/tratamento farmacológico , Prognóstico , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA