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1.
Mol Ther ; 31(1): 119-133, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36146933

RESUMEN

The local microenvironment where tumors develop can shape cancer progression and therapeutic outcome. Emerging evidence demonstrate that the efficacy of immune-checkpoint blockade (ICB) is undermined by fibrotic tumor microenvironment (TME). The majority of hepatocellular carcinoma (HCC) develops in liver fibrosis, in which the stromal and immune components may form a barricade against immunotherapy. Here, we report that nanodelivery of a programmed death-ligand 1 (PD-L1) trap gene exerts superior efficacy in treating fibrosis-associated HCC when compared with the conventional monoclonal antibody (mAb). In two fibrosis-associated HCC models induced by carbon tetrachloride and a high-fat, high-carbohydrate diet, the PD-L1 trap induced significantly larger tumor regression than mAb with no evidence of toxicity. Mechanistic studies revealed that PD-L1 trap, but not mAb, consistently reduced the M2 macrophage proportion in the fibrotic liver microenvironment and promoted cytotoxic interferon gamma (IFNγ)+tumor necrosis factor α (TNF-α)+CD8+T cell infiltration to the tumor. Moreover, PD-L1 trap treatment was associated with decreased tumor-infiltrating polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) accumulation, resulting in an inflamed TME with a high cytotoxic CD8+T cell/PMN-MDSC ratio conductive to anti-tumor immune response. Single-cell RNA sequencing analysis of two clinical cohorts demonstrated preferential PD-L1 expression in M2 macrophages in the fibrotic liver, thus supporting the translational potential of nano-PD-L1 trap for fibrotic HCC treatment.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamiento farmacológico , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Antineoplásicos/uso terapéutico , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Cirrosis Hepática/etiología , Cirrosis Hepática/tratamiento farmacológico , Microambiente Tumoral
2.
Gut ; 72(9): 1758-1773, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37019619

RESUMEN

OBJECTIVE: Therapy-induced tumour microenvironment (TME) remodelling poses a major hurdle for cancer cure. As the majority of patients with hepatocellular carcinoma (HCC) exhibits primary or acquired resistance to antiprogrammed cell death (ligand)-1 (anti-PD-[L]1) therapies, we aimed to investigate the mechanisms underlying tumour adaptation to immune-checkpoint targeting. DESIGN: Two immunotherapy-resistant HCC models were generated by serial orthotopic implantation of HCC cells through anti-PD-L1-treated syngeneic, immunocompetent mice and interrogated by single-cell RNA sequencing (scRNA-seq), genomic and immune profiling. Key signalling pathway was investigated by lentiviral-mediated knockdown and pharmacological inhibition, and further verified by scRNA-seq analysis of HCC tumour biopsies from a phase II trial of pembrolizumab (NCT03419481). RESULTS: Anti-PD-L1-resistant tumours grew >10-fold larger than parental tumours in immunocompetent but not immunocompromised mice without overt genetic changes, which were accompanied by intratumoral accumulation of myeloid-derived suppressor cells (MDSC), cytotoxic to exhausted CD8+ T cell conversion and exclusion. Mechanistically, tumour cell-intrinsic upregulation of peroxisome proliferator-activated receptor-gamma (PPARγ) transcriptionally activated vascular endothelial growth factor-A (VEGF-A) production to drive MDSC expansion and CD8+ T cell dysfunction. A selective PPARγ antagonist triggered an immune suppressive-to-stimulatory TME conversion and resensitised tumours to anti-PD-L1 therapy in orthotopic and spontaneous HCC models. Importantly, 40% (6/15) of patients with HCC resistant to pembrolizumab exhibited tumorous PPARγ induction. Moreover, higher baseline PPARγ expression was associated with poorer survival of anti-PD-(L)1-treated patients in multiple cancer types. CONCLUSION: We uncover an adaptive transcriptional programme by which tumour cells evade immune-checkpoint targeting via PPARγ/VEGF-A-mediated TME immunosuppression, thus providing a strategy for counteracting immunotherapeutic resistance in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratones , Animales , Carcinoma Hepatocelular/patología , Factor A de Crecimiento Endotelial Vascular , Neoplasias Hepáticas/patología , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , PPAR gamma , Microambiente Tumoral , Antígeno B7-H1
3.
Gut ; 69(2): 365-379, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31076403

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC), mostly developed in fibrotic/cirrhotic liver, exhibits relatively low responsiveness to immune checkpoint blockade (ICB) therapy. As myeloid-derived suppressor cell (MDSC) is pivotal for immunosuppression, we investigated its role and regulation in the fibrotic microenvironment with an aim of developing mechanism-based combination immunotherapy. DESIGN: Functional significance of MDSCs was evaluated by flow cytometry using two orthotopic HCC models in fibrotic liver setting via carbon tetrachloride or high-fat high-carbohydrate diet and verified by clinical specimens. Mechanistic studies were conducted in human hepatic stellate cell (HSC)-peripheral blood mononuclear cell culture systems and fibrotic-HCC patient-derived MDSCs. The efficacy of single or combined therapy with anti-programmed death-1-ligand-1 (anti-PD-L1) and a clinically trialled BET bromodomain inhibitor i-BET762 was determined. RESULTS: Accumulation of monocytic MDSCs (M-MDSCs), but not polymorphonuclear MDSCs, in fibrotic livers significantly correlated with reduced tumour-infiltrating lymphocytes (TILs) and increased tumorigenicity in both mouse models. In human HCCs, the tumour-surrounding fibrotic livers were markedly enriched with M-MDSC, with its surrogate marker CD33 significantly associated with aggressive tumour phenotypes and poor survival rates. Mechanistically, activated HSCs induced monocyte-intrinsic p38 MAPK signalling to trigger enhancer reprogramming for M-MDSC development and immunosuppression. Treatment with p38 MAPK inhibitor abrogated HSC-M-MDSC crosstalk to prevent HCC growth. Concomitant with patient-derived M-MDSC suppression by i-BET762, combined treatment with anti-PD-L1 synergistically enhanced TILs, resulting in tumour eradication and prolonged survival in the fibrotic-HCC mouse model. CONCLUSION: Our results signify how non-tumour-intrinsic properties in the desmoplastic microenvironment can be exploited to reinstate immunosurveillance, providing readily translatable combination strategies to empower HCC immunotherapy.


Asunto(s)
Carcinoma Hepatocelular/terapia , Inmunoterapia/métodos , Neoplasias Hepáticas/terapia , Animales , Antígeno B7-H1/antagonistas & inhibidores , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/inmunología , Reprogramación Celular/inmunología , Ciclopropanos/farmacología , Ciclopropanos/uso terapéutico , Células Estrelladas Hepáticas/inmunología , Humanos , Tolerancia Inmunológica , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas Experimentales/etiología , Neoplasias Hepáticas Experimentales/inmunología , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/terapia , Masculino , Ratones Endogámicos C57BL , Monocitos/inmunología , Células Supresoras de Origen Mieloide/inmunología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas/farmacología , Piridinas/uso terapéutico , Transducción de Señal/fisiología , Células Tumorales Cultivadas , Microambiente Tumoral , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología
4.
Cell Biol Toxicol ; 36(5): 399-416, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32002708

RESUMEN

Androgen deprivation therapy (ADT) via surgical or chemical castration frequently fails to halt lethal castration-resistant prostate cancer (CRPC), which is induced by multiple mechanisms involving constitutive androgen receptor (AR) splice variants, AR mutation, and/or de novo androgen synthesis. The AR N-terminal domain (NTD) possesses most transcriptional activity and is proposed as a potential target for CRPC drug development. We constructed a screening system targeting AR-NTD transcription activity to screening a compound library and identified a novel small molecule compound named QW07. The function evaluation and mechanism investigation of QW07 were carried out in vitro and in vivo. QW07 bound to AR-NTD directly, blocked the transactivation of AR-NTD, blocked interactions between co-regulatory proteins and androgen response elements (AREs), inhibited the expression of genes downstream of AR, and inhibited prostate cancer growth in vitro and in vivo. QW07 was demonstrated as an AR-NTD-specific antagonist with the potential to inhibit both canonical and variant-mediated AR signaling to regress the CRPC xenografts and is proposed as a lead compound for a specific antagonist targeting AR-NTD.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Receptores Androgénicos/química , Receptores Androgénicos/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/patología , Dominios Proteicos , Inducción de Remisión , Elementos de Respuesta/genética , Transcripción Genética/efectos de los fármacos
5.
Nucleic Acids Res ; 46(17): 8832-8847, 2018 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-29992318

RESUMEN

Genomic sequencing of hepatocellular carcinoma (HCC) uncovers a paucity of actionable mutations, underscoring the necessity to exploit epigenetic vulnerabilities for therapeutics. In HCC, EZH2-mediated H3K27me3 represents a major oncogenic chromatin modification, but how it modulates the therapeutic vulnerability of signaling pathways remains unknown. Here, we show EZH2 acts antagonistically to AKT signaling in maintaining H3K27 methylome through epigenetic silencing of IGFBP4. ChIP-seq revealed enrichment of Ezh2/H3K27me3 at silenced loci in HBx-transgenic mouse-derived HCCs, including Igfbp4 whose down-regulation significantly correlated with EZH2 overexpression and poor survivals of HCC patients. Functional characterizations demonstrated potent growth- and invasion-suppressive functions of IGFBP4, which was associated with transcriptomic alterations leading to deregulation of multiple signaling pathways. Mechanistically, IGFBP4 stimulated AKT/EZH2 phosphorylation to abrogate H3K27me3-mediated silencing, forming a reciprocal feedback loop that suppressed core transcription factor networks (FOXA1/HNF1A/HNF4A/KLF9/NR1H4) for normal liver homeostasis. Consequently, the in vivo tumorigenicity of IGFBP4-silenced HCC cells was vulnerable to pharmacological inhibition of EZH2, but not AKT. Our study unveils chromatin regulation of a novel liver tumor suppressor IGFBP4, which constitutes an AKT-EZH2 reciprocal loop in driving H3K27me3-mediated epigenetic reprogramming. Defining the aberrant chromatin landscape of HCC sheds light into the mechanistic basis of effective EZH2-targeted inhibition.


Asunto(s)
Carcinogénesis/genética , Carcinoma Hepatocelular/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Código de Histonas/genética , Histonas/metabolismo , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/deficiencia , Neoplasias Hepáticas/genética , Proteínas Supresoras de Tumor/deficiencia , Animales , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Femenino , Humanos , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/fisiología , Neoplasias Hepáticas Experimentales/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones Transgénicos , Terapia Molecular Dirigida , Pronóstico , Mapeo de Interacción de Proteínas , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Neoplásico/genética , Análisis de Secuencia de ARN , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/fisiología , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Comput Struct Biotechnol J ; 23: 954-971, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38385061

RESUMEN

The field of cancer genomics and transcriptomics has evolved from targeted profiling to swift sequencing of individual tumor genome and transcriptome. The steady growth in genome, epigenome, and transcriptome datasets on a genome-wide scale has significantly increased our capability in capturing signatures that represent both the intrinsic and extrinsic biological features of tumors. These biological differences can help in precise molecular subtyping of cancer, predicting tumor progression, metastatic potential, and resistance to therapeutic agents. In this review, we summarized the current development of genomic, methylomic, transcriptomic, proteomic and metabolic signatures in the field of cancer research and highlighted their potentials in clinical applications to improve diagnosis, prognosis, and treatment decision in cancer patients.

7.
Cell Biosci ; 14(1): 37, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515213

RESUMEN

BACKGROUND: Glioma is a highly heterogeneous brain tumor categorized into World Health Organization (WHO) grades 1-4 based on its malignancy. The suppressive immune microenvironment of glioma contributes significantly to unfavourable patient outcomes. However, the cellular composition and their complex interplays within the glioma environment remain poorly understood, and reliable prognostic markers remain elusive. Therefore, in-depth exploration of the tumor microenvironment (TME) and identification of predictive markers are crucial for improving the clinical management of glioma patients. RESULTS: Our analysis of single-cell RNA-sequencing data from glioma samples unveiled the immunosuppressive role of tumor-associated macrophages (TAMs), mediated through intricate interactions with tumor cells and lymphocytes. We also discovered the heterogeneity within TAMs, among which a group of suppressive TAMs named TAM-SPP1 demonstrated a significant association with Epidermal Growth Factor Receptor (EGFR) amplification, impaired T cell response and unfavourable patient survival outcomes. Furthermore, by leveraging genomic and transcriptomic data from The Cancer Genome Atlas (TCGA) dataset, two distinct molecular subtypes with a different constitution of TAMs, EGFR status and clinical outcomes were identified. Exploiting the molecular differences between these two subtypes, we developed a four-gene-based prognostic model. This model displayed strong associations with an elevated level of suppressive TAMs and could be used to predict anti-tumor immune response and prognosis in glioma patients. CONCLUSION: Our findings illuminated the molecular and cellular mechanisms that shape the immunosuppressive microenvironment in gliomas, providing novel insights into potential therapeutic targets. Furthermore, the developed prognostic model holds promise for predicting immunotherapy response and assisting in more precise risk stratification for glioma patients.

8.
JHEP Rep ; 6(7): 101087, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38882672

RESUMEN

Background & Aims: Recent studies demonstrated the importance of fibrosis in promoting an immunosuppressive liver microenvironment and thereby aggressive hepatocellular carcinoma (HCC) growth and resistance to immune checkpoint blockade (ICB), particularly via monocyte-to-monocytic myeloid-derived suppressor cell (M-MDSC) differentiation triggered by hepatic stellate cells (HSCs). We thus aimed to identify druggable targets in these immunosuppressive myeloid cells for HCC therapy. Methods: M-MDSC signature genes were identified by integrated transcriptomic analysis of a human HSC-monocyte culture system and tumor-surrounding fibrotic livers of patients with HCC. Mechanistic and functional studies were conducted using in vitro-generated and patient-derived M-MDSCs. The therapeutic efficacy of a M-MDSC targeting approach was determined in fibrosis-associated HCC mouse models. Results: We uncovered over-expression of protein phosphatase 1 regulatory subunit 15A (PPP1R15A), a myeloid cell-enriched endoplasmic reticulum stress modulator, in human M-MDSCs that correlated with poor prognosis and ICB non-responsiveness in patients with HCC. Blocking TGF-ß signaling reduced PPP1R15A expression in HSC-induced M-MDSCs, whereas treatment of monocytes by TGF-ß upregulated PPP1R15A, which in turn promoted ARG1 and S100A8/9 expression in M-MDSCs and reduced T-cell proliferation. Consistently, lentiviral-mediated knockdown of Ppp1r15a in vivo significantly reduced ARG1+S100A8/9+ M-MDSCs in fibrotic liver, leading to elevated intratumoral IFN-γ+GZMB+CD8+ T cells and enhanced anti-tumor efficacy of ICB. Notably, pharmacological inhibition of PPP1R15A by Sephin1 reduced the immunosuppressive potential but increased the maturation status of fibrotic HCC patient-derived M-MDSCs. Conclusions: PPP1R15A+ M-MDSC cells are involved in immunosuppression in HCC development and represent a novel potential target for therapies. Impact and implications: Our cross-species analysis has identified PPP1R15A as a therapeutic target governing the anti-T-cell activities of fibrosis-associated M-MDSCs (monocytic myeloid-derived suppressor cells). The results from the preclinical models show that specific inhibition of PPP1R15A can break the immunosuppressive barrier to restrict hepatocellular carcinoma growth and enhance the efficacy of immune checkpoint blockade. PPP1R15A may also function as a prognostic and/or predictive biomarker in patients with hepatocellular carcinoma.

9.
Cell Mol Immunol ; 19(7): 834-847, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35595819

RESUMEN

Obesity is a major risk factor for cancers including hepatocellular carcinoma (HCC) that develops from a background of non-alcoholic fatty liver disease (NAFLD). Hypercholesterolemia is a common comorbidity of obesity. Although cholesterol biosynthesis mainly occurs in the liver, its role in HCC development of obese people remains obscure. Using high-fat high-carbohydrate diet-associated orthotopic and spontaneous NAFLD-HCC mouse models, we found that hepatic cholesterol accumulation in obesity selectively suppressed natural killer T (NKT) cell-mediated antitumor immunosurveillance. Transcriptome analysis of human liver revealed aberrant cholesterol metabolism and NKT cell dysfunction in NAFLD patients. Notably, cholesterol-lowering rosuvastatin restored NKT expansion and cytotoxicity to prevent obesogenic diet-promoted HCC development. Moreover, suppression of hepatic cholesterol biosynthesis by a mammalian target of rapamycin (mTOR) inhibitor vistusertib preceded tumor regression, which was abolished by NKT inactivation but not CD8+ T cell depletion. Mechanistically, sterol regulatory element-binding protein 2 (SREBP2)-driven excessive cholesterol production from hepatocytes induced lipid peroxide accumulation and deficient cytotoxicity in NKT cells, which were supported by findings in people with obesity, NAFLD and NAFLD-HCC. This study highlights mTORC1/SREBP2/cholesterol-mediated NKT dysfunction in the tumor-promoting NAFLD liver microenvironment, providing intervention strategies that invigorating NKT cells to control HCC in the obesity epidemic.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células T Asesinas Naturales , Enfermedad del Hígado Graso no Alcohólico , Animales , Colesterol/metabolismo , Humanos , Hígado/patología , Mamíferos , Ratones , Monitorización Inmunológica/efectos adversos , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad/patología , Microambiente Tumoral
10.
Sci Transl Med ; 13(588)2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33827976

RESUMEN

Insufficient T cell infiltration into noninflamed tumors, such as hepatocellular carcinoma (HCC), restricts the effectiveness of immune-checkpoint blockade (ICB) for a subset of patients. Epigenetic therapy provides further opportunities to rewire cancer-associated transcriptional programs, but whether and how selective epigenetic inhibition counteracts the immune-excluded phenotype remain incompletely defined. Here, we showed that pharmacological inhibition of histone deacetylase 8 (HDAC8), a histone H3 lysine 27 (H3K27)-specific isozyme overexpressed in a variety of human cancers, thwarts HCC tumorigenicity in a T cell-dependent manner. The tumor-suppressive effect of selective HDAC8 inhibition was abrogated by CD8+ T cell depletion or regulatory T cell adoptive transfer. Chromatin profiling of human HDAC8-expressing HCCs revealed genome-wide H3K27 deacetylation in 1251 silenced enhancer-target gene pairs that are enriched in metabolic and immune regulators. Mechanistically, down-regulation of HDAC8 increased global and enhancer acetylation of H3K27 to reactivate production of T cell-trafficking chemokines by HCC cells, thus relieving T cell exclusion in both immunodeficient and humanized mouse models. In an HCC preclinical model, selective HDAC8 inhibition increased tumor-infiltrating CD8+ T cells and potentiated eradication of established hepatomas by anti-PD-L1 therapy without evidence of toxicity. Mice treated with HDAC8 and PD-L1 coblockade were protected against subsequent tumor rechallenge as a result of the induction of memory T cells and remained tumor-free for greater than 15 months. Collectively, our study demonstrates that selective HDAC8 inhibition elicits effective and durable responses to ICB by co-opting adaptive immunity through enhancer reprogramming.


Asunto(s)
Carcinoma Hepatocelular , Inhibidores de Histona Desacetilasas , Inhibidores de Puntos de Control Inmunológico , Neoplasias Hepáticas , Animales , Linfocitos T CD8-positivos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Ratones , Proteínas Represoras
11.
Cell Mol Immunol ; 18(4): 1005-1015, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32879468

RESUMEN

The liver is an immunologically tolerant organ and a common metastatic site of multiple cancer types. Although a role for cancer cell invasion programs has been well characterized, whether and how liver-intrinsic factors drive metastatic spread is incompletely understood. Here, we show that aberrantly activated hepatocyte-intrinsic cell cycle-related kinase (CCRK) signaling in chronic liver diseases is critical for cancer metastasis by reprogramming an immunosuppressive microenvironment. Using an inducible liver-specific transgenic model, we found that CCRK overexpression dramatically increased both B16F10 melanoma and MC38 colorectal cancer (CRC) metastasis to the liver, which was highly infiltrated by polymorphonuclear-myeloid-derived suppressor cells (PMN-MDSCs) and lacking natural killer T (NKT) cells. Depletion of PMN-MDSCs in CCRK transgenic mice restored NKT cell levels and their interferon gamma production and reduced liver metastasis to 2.7% and 0.7% (metastatic tumor weights) in the melanoma and CRC models, respectively. Mechanistically, CCRK activated nuclear factor-kappa B (NF-κB) signaling to increase the PMN-MDSC-trafficking chemokine C-X-C motif ligand 1 (CXCL1), which was positively correlated with liver-infiltrating PMN-MDSC levels in CCRK transgenic mice. Accordingly, CRC liver metastasis patients exhibited hyperactivation of hepatic CCRK/NF-κB/CXCL1 signaling, which was associated with accumulation of PMN-MDSCs and paucity of NKT cells compared to healthy liver transplantation donors. In summary, this study demonstrates that immunosuppressive reprogramming by hepatic CCRK signaling undermines antimetastatic immunosurveillance. Our findings offer new mechanistic insights and therapeutic targets for liver metastasis intervention.


Asunto(s)
Ciclo Celular , Neoplasias Colorrectales/inmunología , Neoplasias Hepáticas/inmunología , Melanoma Experimental/inmunología , Células Supresoras de Origen Mieloide/inmunología , Células T Asesinas Naturales/inmunología , Microambiente Tumoral , Animales , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
12.
Microb Biotechnol ; 13(3): 722-737, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31758659

RESUMEN

Ethyl-N-dodecanoyl-l-arginate hydrochloride (LAE, ethyl lauroyl arginate HCl) is a cationic surfactant used as a food preservative with broad-spectrum antibacterial activities. However, its resistance development, influences on gut microbiome and molecular target are unclear. In this study, bacteria were stimulated by LAE for 30 days to test the bacterial resistance. Several infected animal models were used to evaluate the antibacterial effect of LAE in vivo. Mice were orally treated with LAE to test its effect on animal growth. The influence of LAE on mice gut microbiome was analysed by 16S rDNA sequencing. The results indicated that Escherichia coli did not develop resistance to LAE. LAE significantly combats bacterial infection in mice, ducklings and piglets. Moreover, LAE promotes mouse weight gain without changing body composition or reducing animal vitality, and induces lower hepatotoxicity than ampicillin. In the mouse gut microbiome assessment and characterization, LAE modifies host gut microbiota structure. Mechanistically, LAE specifically binds to acidic phospholipids including phosphatidylserine, depolarizes the membrane and disrupts the bacterial membrane followed by bacterial growth inhibition. This study investigates the molecular mechanism of LAE as well as its antibacterial functions in poultry and livestock. Our data suggest LAE is a potential antibacterial agent in animal health.


Asunto(s)
Arginina/análogos & derivados , Bacterias , Microbioma Gastrointestinal , Animales , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Arginina/farmacología , Arginina/uso terapéutico , Bacterias/efectos de los fármacos , Bacterias/genética , Infecciones Bacterianas/tratamiento farmacológico , Biodiversidad , Membrana Celular/efectos de los fármacos , Patos , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , ARN Ribosómico 16S/genética , Porcinos
13.
Pharmacol Ther ; 186: 138-151, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29360538

RESUMEN

Cyclin-dependent kinase 20 (CDK20), or more commonly referred to as cell cycle-related kinase (CCRK), is the latest member of CDK family with strong linkage to human cancers. Accumulating studies have reported the consistent overexpression of CCRK in cancers arising from brain, colon, liver, lung and ovary. Such aberrant up-regulation of CCRK is clinically significant as it correlates with tumor staging, shorter patient survival and poor prognosis. Intriguingly, the signalling molecules perturbed by CCRK are divergent and cancer-specific, including the cell cycle regulators CDK2, cyclin D1, cyclin E and RB in glioblastoma, ovarian carcinoma and colorectal cancer, and KEAP1-NRF2 cytoprotective pathway in lung cancer. In hepatocellular carcinoma (HCC), CCRK mediates virus-host interaction to promote hepatitis B virus-associated tumorigenesis. Further mechanistic analyses reveal that CCRK orchestrates a self-reinforcing circuitry comprising of AR, GSK3ß, ß-catenin, AKT, EZH2, and NF-κB signalling for transcriptional and epigenetic regulation of oncogenes and tumor suppressor genes. Notably, EZH2 and NF-κB in this circuit have been recently shown to induce IL-6 production to facilitate tumor immune evasion. Concordantly, in a hepatoma preclinical model, ablation of Ccrk disrupts the immunosuppressive tumor microenvironment and enhances the therapeutic efficacy of immune checkpoint blockade via potentiation of anti-tumor T cell responses. In this review, we summarized the multifaceted tumor-intrinsic and -extrinsic functions of CCRK, which represents a novel signalling hub exploitable in cancer immunotherapy.


Asunto(s)
Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Inmunoterapia/métodos , Neoplasias/inmunología , Neoplasias/terapia , Transducción de Señal/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Quinasas Ciclina-Dependientes/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Terapia Molecular Dirigida , Neoplasias/enzimología , Neoplasias/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Microambiente Tumoral/inmunología , Quinasa Activadora de Quinasas Ciclina-Dependientes
14.
Nat Commun ; 9(1): 5214, 2018 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-30523261

RESUMEN

Obesity increases the risk of hepatocellular carcinoma (HCC) especially in men, but the molecular mechanism remains obscure. Here, we show that an androgen receptor (AR)-driven oncogene, cell cycle-related kinase (CCRK), collaborates with obesity-induced pro-inflammatory signaling to promote non-alcoholic steatohepatitis (NASH)-related hepatocarcinogenesis. Lentivirus-mediated Ccrk ablation in liver of male mice fed with high-fat high-carbohydrate diet abrogates not only obesity-associated lipid accumulation, glucose intolerance and insulin resistance, but also HCC development. Mechanistically, CCRK fuels a feedforward loop by inducing STAT3-AR promoter co-occupancy and transcriptional up-regulation, which in turn activates mTORC1/4E-BP1/S6K/SREBP1 cascades via GSK3ß phosphorylation. Moreover, hepatic CCRK induction in transgenic mice stimulates mTORC1-dependent G-csf expression to enhance polymorphonuclear myeloid-derived suppressor cell recruitment and tumorigenicity. Finally, the STAT3-AR-CCRK-mTORC1 pathway components are concordantly over-expressed in human NASH-associated HCCs. These findings unveil the dual roles of an inflammatory-CCRK circuitry in driving metabolic and immunosuppressive reprogramming through mTORC1 activation, thereby establishing a pro-tumorigenic microenvironment for HCC development.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Neoplasias Hepáticas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Obesidad/metabolismo , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Quinasas Ciclina-Dependientes/genética , Femenino , Células Hep G2 , Humanos , Tolerancia Inmunológica/genética , Tolerancia Inmunológica/inmunología , Inflamación/genética , Inflamación/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones Transgénicos , Obesidad/genética , Obesidad/inmunología , Interferencia de ARN , Tratamiento con ARN de Interferencia , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
15.
Sci China Life Sci ; 60(4): 397-403, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28321657

RESUMEN

Hemostasis is a major challenge in surgical procedures and traumas. Conventional hemostatic methods have limited efficacy and may cause additional tissue damage. In this study, we designed a novel hemostatic agent based on the in situ gel formation of gelatin cross-linked by a novel microbial transglutaminase (mTGase), in which the amino acid sequences differed from commercial mTGases. The new hemostatic agent showed the same biochemical crosslinking chemistry as the final stages of the blood coagulation cascade while using gelatin as a "structural" protein (rather than fibrin) and a calcium-independent mTGase as the crosslinking catalyst (rather than factor XIIIa). In rat liver hemostasis models, the hemostatic agent not only showed a similar hemostatic effect as that of SURGIFLO® (positive control), but also stronger adhesion strength and elasticity than SURGIFLO®. Therefore, this biomimetic gelatin-mTGase mix hemostatic is a novel and effective surgical sealant.


Asunto(s)
Gelatina/química , Hemostáticos , Streptomycetaceae/enzimología , Transglutaminasas/química , Secuencia de Aminoácidos , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Homología de Secuencia de Aminoácido
16.
Nat Genet ; 49(10): 1428-1436, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28869592

RESUMEN

We propose a new method for determining the target genes of transcriptional enhancers in specific cells and tissues. It combines global trends across many samples and sample-specific information, and considers the joint effect of multiple enhancers. Our method outperforms existing methods when predicting the target genes of enhancers in unseen samples, as evaluated by independent experimental data. Requiring few types of input data, we are able to apply our method to reconstruct the enhancer-target networks in 935 samples of human primary cells, tissues and cell lines, which constitute by far the largest set of enhancer-target networks. The similarity of these networks from different samples closely follows their cell and tissue lineages. We discover three major co-regulation modes of enhancers and find defense-related genes often simultaneously regulated by multiple enhancers bound by different transcription factors. We also identify differentially methylated enhancers in hepatocellular carcinoma (HCC) and experimentally confirm their altered regulation of HCC-related genes.


Asunto(s)
Elementos de Facilitación Genéticos , Epigénesis Genética , Regulación de la Expresión Génica , Redes Reguladoras de Genes/genética , Transcripción Genética , Carcinoma Hepatocelular/genética , Línea Celular , Metilación de ADN , Genes Relacionados con las Neoplasias , Humanos , Células K562 , Neoplasias Hepáticas/genética , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Fosfoproteínas/biosíntesis , Fosfoproteínas/genética , Cultivo Primario de Células , Proteínas de Unión al ARN/biosíntesis , Proteínas de Unión al ARN/genética , Telomerasa/biosíntesis , Telomerasa/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
Sci Rep ; 6: 33434, 2016 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-27633259

RESUMEN

Inhibition of angiogenesis is considered as one of the desirable pathways for the treatment of tumor growth and metastasis. Herein we demonstrated that a series of pyridinyl-thiazolyl carboxamide derivatives were designed, synthesized and examined against angiogenesis through a colony formation and migration assays of human umbilical vein endothelial cells (HUVECs) in vitro. A structure-activity relationship (SAR) study was carried out and optimization toward this series of compounds resulted in the discovery of N-(3-methoxyphenyl)-4-methyl-2-(2-propyl-4-pyridinyl)thiazole-5-carboxamide (3k). The results indicated that compound 3k showed similar or better effects compared to Vandetanib in suppressing HUVECs colony formation and migration as well as VEGF-induced angiogenesis in the aortic ring spreading model and chick embryo chorioallantoic membrane (CAM) model. More importantly, compound 3k also strongly blocked tumor growth with the dosage of 30 mg/kg/day, and subsequent mechanism exploration suggested that this series of compounds took effect mainly through angiogenesis signaling pathways. Together, these results suggested compound 3k may serve as a lead for a novel class of angiogenesis inhibitors for cancer treatments.


Asunto(s)
Descubrimiento de Drogas , Neoplasias/irrigación sanguínea , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Transducción de Señal , Tiazoles/uso terapéutico , Animales , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Embrión de Pollo , Ensayo de Unidades Formadoras de Colonias , Diseño de Fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Ratones Desnudos , Neoplasias/patología , Neovascularización Patológica/patología , Fosforilación/efectos de los fármacos , Piperidinas/farmacología , Piperidinas/uso terapéutico , Quinazolinas/farmacología , Quinazolinas/uso terapéutico , Ratas Sprague-Dawley , Fibras de Estrés/efectos de los fármacos , Fibras de Estrés/metabolismo , Tiazoles/síntesis química , Tiazoles/química , Tiazoles/farmacología , Cicatrización de Heridas/efectos de los fármacos
18.
Water Res ; 47(11): 3624-34, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23726698

RESUMEN

By doping a proper amount of Mg(2+) (~10%) into α-Fe2O3 during a solvent thermal process, ultrafine magnesium ferrite (Mg0.27Fe2.50O4) nanocrystallites were successfully synthesized with the assistance of in situ self-formed NaCl "cage" to confine their crystal growth. Their ultrafine size (average size of ~3.7 nm) and relatively low Mg-content conferred on them a superparamagnetic behavior with a high saturation magnetization (32.9 emu/g). The ultrafine Mg0.27Fe2.50O4 nanoadsorbent had a high specific surface area of ~438.2 m(2)/g, and demonstrated a superior arsenic removal performance on both As(III) and As(V) at near neutral pH condition. Its adsorption capacities on As(III) and As(V) were found to be no less than 127.4 mg/g and 83.2 mg/g, respectively. Its arsenic adsorption mechanism was found to follow the inner-sphere complex mechanism, and abundant hydroxyl groups on its surface played the major role in its superior arsenic adsorption performance. It could be easily separated from treated water bodies with magnetic separation, and could be easily regenerated and reused while maintaining a high arsenic removal efficiency. This novel superparamagnetic magnesium ferrite nanoadsorbent may offer a simple single step adsorption treatment option to remove arsenic contamination from water without the pre-/post-treatment requirement for current industrial practice.


Asunto(s)
Arsénico/aislamiento & purificación , Nanopartículas/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Arsénico/química , Fraccionamiento Químico/métodos , China , Equipo Reutilizado , Compuestos Férricos/química , Agua Dulce/química , Concentración de Iones de Hidrógeno , Cinética , Lagos , Compuestos de Magnesio/química , Magnetismo , Nanopartículas/ultraestructura , Propiedades de Superficie , Contaminantes Químicos del Agua/química , Difracción de Rayos X
19.
Nanoscale Res Lett ; 7(1): 238, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22548846

RESUMEN

The microwave absorption properties of Ni/(C, silicides) nanocapsules prepared by an arc discharge method have been studied. The composition and the microstructure of the Ni/(C, silicides) nanocapsules were determined by means of X-ray diffraction, X-ray photoelectric spectroscopy, and transmission electron microscope observations. Silicides, in the forms of SiOx and SiC, mainly exist in the shells of the nanocapsules and result in a large amount of defects at the 'core/shell' interfaces as well as in the shells. The complex permittivity and microwave absorption properties of the Ni/(C, silicides) nanocapsules are improved by the doped silicides. Compared with those of Ni/C nanocapsules, the positions of maximum absorption peaks of the Ni/(C, silicides) nanocapsules exhibit large red shifts. An electric dipole model is proposed to explain this red shift phenomenon.

20.
J Hazard Mater ; 192(1): 131-8, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21684075

RESUMEN

Ultrafine iron oxide (α-Fe(2)O(3)) nanoparticles were synthesized by a solvent thermal process and used to remove arsenic ions from both lab-prepared and natural water samples. The α-Fe(2)O(3) nanoparticles assumed a near-sphere shape with an average size of about 5 nm. They aggregated into a highly porous structure with a high specific surface area of ∼ 162 m(2)/g, while their surface was covered by high-affinity hydroxyl groups. The arsenic adsorption experiment results demonstrated that they were effective, especially at low equilibrium arsenic concentrations, in removing both As(III) and As(V) from lab-prepared and natural water samples. Near the neutral pH, the adsorption capacities of the α-Fe(2)O(3) nanoparticles on As(III) and As(V) from lab-prepared samples were found to be no less than 95 mg/g and 47 mg/g, respectively. In the presence of most competing ions, these α-Fe(2)O(3) nanoparticles maintained their arsenic adsorption capacity even at very high competing anion concentrations. Without the pre-oxidation and/or the pH adjustment, these α-Fe(2)O(3) nanoparticles effectively removed both As(III) and As(V) from a contaminated natural lake water sample to meet the USEPA drinking water standard for arsenic.


Asunto(s)
Arsénico/aislamiento & purificación , Nanopartículas del Metal , Solventes/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cristalografía por Rayos X , Cinética , Microscopía Electrónica de Transmisión , Propiedades de Superficie
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