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1.
Cancer Lett ; 589: 216832, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38537774

RESUMEN

Yes-associated protein (YAP) is an essential driver of hepatocellular carcinoma (HCC) progression and the ubiquitin-proteasome system controls its abundance. However, the role of ubiquitin-specific protease 40 (USP40) in YAP stability remains unclear. Here, USP40 was first identified as a novel regulator of YAP abundance and its target genes in HCC cells. USP40 interacted with YAP to remove the lysine 48 (K48)-linked polyubiquitination of YAP at K252 and K315 sites, thereby maintaining YAP stability. USP40 facilitated the proliferation, colony formation, migration and spheroid formation of HCC cells in vitro and promoted HCC growth in vivo in a YAP-dependent manner. In turn, YAP transcriptionally activated USP40 expression in HCC cells. RNA sequencing analysis showed that about 37% of USP40-regulated genes overlapped with YAP-regulated genes. Interestingly, stiffness-induced USP40 upregulation was abolished by YAP knockdown, and USP40 knockdown attenuated stiffness-induced YAP accumulation in HCC cells. Clinical data demonstrated that USP40 was positively associated with YAP expression in HCC tissues and its high expression indicated a poor prognosis. In conclusion, the USP40/YAP positive feedback loop contributes to HCC progression, suggesting that USP40 may be a promising drug target for anti-HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Retroalimentación , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Señalizadoras YAP
2.
Biomaterials ; 307: 122537, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38492523

RESUMEN

Non-small cell lung cancer (NSCLC) brain metastases present a significant treatment challenge due to limited drug delivery efficiency and severe adverse reactions. In this study, we address these challenges by designing a "on/off" switchable crosslinked paclitaxel (PTX) nanocarrier, BPM-PD, with novel ultra-pH-sensitive linkages (pH 6.8 to 6.5). BPM-PD demonstrates a distinct "on/off" switchable release of the anti-cancer drug paclitaxel (PTX) in response to the acidic extratumoral microenvironment. The "off" state of BPM-PD@PTX effectively prevents premature drug release in the blood circulation, blood-brain barrier (BBB)/blood-tumor barrier (BTB), and normal brain tissue, surpassing the clinical PTX-nanoformulation (nab-PTX). Meanwhile, the "on" state facilitates precise delivery to NSCLC brain metastases cells. Compared to nab-PTX, BPM-PD@PTX demonstrates improved therapeutic efficacy with a reduced tumor area (only 14.6%) and extended survival duration, while mitigating adverse reactions (over 83.7%) in aspartate aminotransferase (AST) and alanine aminotransferase (ALT), offering a promising approach for the treatment of NSCLC brain metastases. The precise molecular switch also helped to increase the PTX maximum tolerated dose from 25 mg/kg to 45 mg/kg This research contributes to the field of cancer therapeutics and has significant implications for improving the clinical outcomes of NSCLC patients.


Asunto(s)
Antineoplásicos , Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Paclitaxel/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Microambiente Tumoral
3.
J Cancer Res Clin Oncol ; 149(15): 13591-13605, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37515611

RESUMEN

PURPOSE: This study aimed to assess the actual prognostic significance of different locoregional treatment (LRT) (surgery and radiotherapy) modalities for stage-IV  breast cancer (BC) patients and construct a competing risk nomogram to make precise predictions of the breast cancer-specific death (BCSD) risk among LRT recipients. METHODS: A total of 9279 eligible stage-IV BC patients from the Surveillance Epidemiology and End Results (SEER) database were included in this study. Initially, we evaluated the impact of LRT on survival both before and after the propensity score matching (PSM). Then, we used the Cox hazard proportional model and competing risk model to identify the independent prognostic factors for LRT recipients. Based on the screened variables, a comprehensive nomogram was established. RESULTS: Kaplan-Meier curves demonstrated that LRT significantly prolonged overall survival (OS) and breast cancer-specific survival (BCSS) (P < 0.001). In addition, patients treated with surgery combined with postoperative radiotherapy (PORT) possessed the optimal survival (P < 0.001). Regardless of the surgical modalities, primary tumor resection combined with radiotherapy could ameliorate the prognosis (P < 0.05). Subgroup analysis showed that in patients with T2-T4 stage, PORT had a survival benefit compared with those undergoing surgery combined with preoperative radiotherapy (PRRT) and surgery only. Based on the screened independent prognostic factors, we established a comprehensive nomogram to forecast BCSD in 1 year, 2 years and 3 years, which showed robust predictive ability. CONCLUSION: PORT was associated with a lower BCSD in stage-IV BC patients. The practical nomogram could provide a precise prediction of BCSD for LRT recipients, which was meaningful for patients' individualized management.

4.
Cell Mol Life Sci ; 80(5): 120, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041420

RESUMEN

BACKGROUND: Hypoxia-inducible factors (HIFs) are the most essential endogenous transcription factors in the hypoxic microenvironment and regulate multiple genes involved in the proliferation, migration, invasion, and EMT of hepatocellular carcinoma (HCC) cells. However, the regulatory mechanism of HIFs in driving HCC progression remains poorly understood. METHODS: Gain- and loss-of-function experiments were carried out to investigate the role of TMEM237 in vitro and in vivo. The molecular mechanisms involved in HIF-1α-induced TMEM237 expression and TMEM237-mediated enhancement of HCC progression were confirmed by luciferase reporter, ChIP, IP-MS and Co-IP assays. RESULTS: TMEM237 was identified as a novel hypoxia-responsive gene in HCC. HIF-1α directly bound to the promoter of TMEM237 to transactivate its expression. The overexpression of TMEM237 was frequently detected in HCC and associated with poor clinical outcomes in patients. TMEM237 facilitated the proliferation, migration, invasion, and EMT of HCC cells and promoted tumor growth and metastasis in mice. TMEM237 interacted with NPHP1 and strengthened the interaction between NPHP1 and Pyk2 to trigger the phosphorylation of Pyk2 and ERK1/2, thereby contributing to HCC progression. The TMEM237/NPHP1 axis mediates hypoxia-induced activation of the Pyk2/ERK1/2 pathway in HCC cells. CONCLUSIONS: Our study demonstrated that HIF-1α-activated TMEM237 interacted with NPHP1 to activate the Pyk2/ERK pathway, thereby promoting HCC progression.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proteínas del Citoesqueleto/metabolismo , Quinasa 2 de Adhesión Focal/metabolismo , Hipoxia/genética , Neoplasias Hepáticas/metabolismo , Sistema de Señalización de MAP Quinasas , Microambiente Tumoral , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo
5.
Cell Biosci ; 13(1): 62, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944972

RESUMEN

The aim of the present study was to elucidate the evolutionary trajectory of colon cells from normal colon mucosa, to adenoma, then to carcinoma in the same microenvironment. Normal colon, adenoma and carcinoma tissues from the same patient were analyzed by single-cell sequencing, which perfectly simulated the process of time-dependent colon cancer due to the same microenvironment. A total of 22 cell types were identified. Results suggest the presence of dominant clones of same cells including C2 goblet cell, epithelial cell subtype 1 (Epi1), enterocyte cell subset 0 (Entero0), and Entero5 in carcinoma. Epi1 and Entero0 were Co-enriched in antibacterial and IL-17 signaling, Entero5 was enriched in immune response and mucin-type O-glycan biosynthesis. We discovered new colon cancer related genes including AC007952.4, NEK8, CHRM3, ANO7, B3GNT6, NEURL1, ODC1 and KCNMA1. The function of TBC1D4, LTB, C2CD4A, AND GBP4/5 in T cells needs to be clarified. We used colon samples from the same person, which provide new information for colon cancer therapy.

6.
Front Genet ; 13: 916672, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36051699

RESUMEN

Objective : Our study aims to summarize and analyze the clinical characteristics of transient infantile hypertriglyceridemia (HTGTI) and variants in the glycerol-3-phosphate dehydrogenase 1 (GPD1) gene and the effect of HTGTI on the protein structure of GPD1. Methods: Retrospective analysis, using the general data, symptoms, signs, and auxiliary examinations, was performed on patients with HTGTI, which were confirmed by genetic testing in our hospital and reported cases online. The clinical data were analyzed using statistical and bioinformatic approaches. Results: A total of 31 genetically confirmed HTGTI patients were collected from our hospital and cases reported in the literature. The clinical manifestations showed the median age of onset was 6.0 (1.9, 12.0) months. All the patients had normal psychiatric status, but 22.6% of them presented growth retardation and short stature, 93.5% had hepatomegaly, and 16.1% had splenomegaly. Just a few children were reported with jaundice, cholestasis, and obesity (3.2-6.5%). The laboratory investigations showed that 96.8% of them had hypertriglyceridemia (HTG) with a median level of 3.1 (2.1, 5.5) mmol/L, but only 30.0% had returned to normal during follow-up. In addition, 93.5% of patients had elevated alanine aminotransferase (ALT) with an average level of 92.1 ± 43.5 U/L, while 38.7% had hypercholesterolemia. Upon abdominal imaging, all patients presented fatty liver and liver steatosis, with 66.7% of patients showing hepatic fibrosis. Statistical differences in triglyceride (TG) level were observed in the ≤6 months group compared with the older groups and in the 13 months to 6 years group with >6 years group (H = 22.02, P < 0.05). The restricted cubic spline model showed that severe HTG decreased in the early stage of infants to the normal level; however, it rebounded again to a mild or moderate level after the following days. The genetic test revealed that the main variant types of the GPD1 gene were missense variants (51.6%), followed by splicing variants (35.5%) and nonsense variants (12.9%). Of patients, 87.1% had homozygous variants, with the most frequent loci being c.361-1G > C and c.895G > A. Conclusion: The common manifestations of HTGTI were HTG, hepatomegaly, elevated liver transaminases, and hepatic steatosis in early infancy. However, the recurrence of aberrant HTG may pose long-term detrimental effects on HTGTI patients.

7.
J Vis Exp ; (180)2022 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35253791

RESUMEN

Identification of open reading frames (ORFs), especially those encoding small peptides and being actively translated under specific physiological contexts, is critical for comprehensive annotations of context-dependent translatomes. Ribosome profiling, a technique for detecting the binding locations and densities of translating ribosomes on RNA, offers an avenue to rapidly discover where translation is occurring at the genome-wide scale. However, it is not a trivial task in bioinformatics to efficiently and comprehensively identify the translating ORFs for ribosome profiling. Described here is an easy-to-use package, named RiboCode, designed to search for actively translating ORFs of any size from distorted and ambiguous signals in ribosome profiling data. Taking our previously published dataset as an example, this article provides step-by-step instructions for the entire RiboCode pipeline, from preprocessing of the raw data to interpretation of the final output result files. Furthermore, for evaluating the translation rates of the annotated ORFs, procedures for visualization and quantification of ribosome densities on each ORF are also described in detail. In summary, the present article is a useful and timely instruction for the research fields related to translation, small ORFs, and peptides.


Asunto(s)
Biosíntesis de Proteínas , Ribosomas , Biología Computacional/métodos , Sistemas de Lectura Abierta , Ribosomas/genética , Ribosomas/metabolismo , Análisis de Secuencia de ARN/métodos
8.
Nat Immunol ; 22(11): 1403-1415, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34686867

RESUMEN

Tumor-associated macrophages (TAMs) display pro-tumorigenic phenotypes for supporting tumor progression in response to microenvironmental cues imposed by tumor and stromal cells. However, the underlying mechanisms by which tumor cells instruct TAM behavior remain elusive. Here, we uncover that tumor-cell-derived glucosylceramide stimulated unconventional endoplasmic reticulum (ER) stress responses by inducing reshuffling of lipid composition and saturation on the ER membrane in macrophages, which induced IRE1-mediated spliced XBP1 production and STAT3 activation. The cooperation of spliced XBP1 and STAT3 reinforced the pro-tumorigenic phenotype and expression of immunosuppressive genes. Ablation of XBP1 expression with genetic manipulation or ameliorating ER stress responses by facilitating LPCAT3-mediated incorporation of unsaturated lipids to the phosphatidylcholine hampered pro-tumorigenic phenotype and survival in TAMs. Together, we uncover the unexpected roles of tumor-cell-produced lipids that simultaneously orchestrate macrophage polarization and survival in tumors via induction of ER stress responses and reveal therapeutic targets for sustaining host antitumor immunity.


Asunto(s)
Estrés del Retículo Endoplásmico , Retículo Endoplásmico/metabolismo , Membranas Intracelulares/metabolismo , Activación de Macrófagos , Melanoma/metabolismo , Lípidos de la Membrana/metabolismo , Neoplasias Cutáneas/metabolismo , Macrófagos Asociados a Tumores/metabolismo , Animales , Línea Celular Tumoral , Supervivencia Celular , Retículo Endoplásmico/ultraestructura , Glucosilceramidasa/metabolismo , Membranas Intracelulares/ultraestructura , Melanoma/genética , Melanoma/ultraestructura , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Fenotipo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/ultraestructura , Escape del Tumor , Microambiente Tumoral , Macrófagos Asociados a Tumores/ultraestructura , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismo
9.
J Immunother Cancer ; 9(10)2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34642245

RESUMEN

BACKGROUND: Aging has long been thought to be a major risk factor for various types of cancers. However, accumulating evidence indicates increased resistance of old animals to tumor growth. An in-depth understanding of how old individuals defend against tumor invasion requires further investigations. METHODS: We revealed age-associated alterations in tumor-infiltrating immune cells between young and old mice using single-cell RNA and coupled T cell receptor (TCR) sequencing analysis. Multiple bioinformatics methods were adopted to analyze the characteristics of the transcriptome between two groups. To explore the impacts of young and old CD8+ T cells on tumor growth, mice were treated with anti-CD8 antibody every 3 days starting 7 days after tumor inoculation. Flow cytometry was used to validate the differences indicated by sequencing analysis between young and old mice. RESULTS: We found a higher proportion of cytotoxic CD8+ T cells, naturally occurring Tregs, conventional dendritic cell (DC), and M1-like macrophages in tumors of old mice compared with a higher percentage of exhausted CD8+ T cells, induced Tregs, plasmacytoid DC, and M2-like macrophages in young mice. Importantly, TCR diversity analysis showed that top 10 TCR clones consisted primarily of exhausted CD8+ T cells in young mice whereas top clones were predominantly cytotoxic CD8+ T cells in old mice. Old mice had more CD8+ T cells with a 'progenitor' and less 'terminally' exhausted phenotypes than young mice. Consistently, trajectory inference demonstrated that CD8+ T cells preferentially differentiated into cytotoxic cells in old mice in contrast to exhausted cells in young mice. Importantly, elimination of CD8+ T cells in old mice during tumor growth significantly accelerated tumor development. Moreover, senescent features were demonstrated in exhausted but not cytotoxic CD8+ T cells regardless of young and old mice. CONCLUSIONS: Our data revealed that a significantly higher proportion of effector immune cells in old mice defends against tumor progression, providing insights into understanding the altered kinetics of cancer development and the differential response to immunotherapeutic modulation in elderly patients.


Asunto(s)
Inmunoterapia/métodos , Neoplasias/inmunología , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Envejecimiento , Animales , Femenino , Ratones , Microambiente Tumoral
10.
Curr Opin Chem Biol ; 63: 11-18, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33667809

RESUMEN

Chromatin and associated epigenetic marks provide important platforms for gene regulation in response to metabolic changes associated with environmental exposures, including physiological stress, nutritional deprivation, and starvation. Numerous studies have shown that fluctuations of key metabolites can influence chromatin modifications, but their effects on chromatin structure (e.g. chromatin compaction, nucleosome arrangement, and chromatin loops) and how they appropriately deposit specific chemical modification on chromatin are largely unknown. Here, focusing on methionine metabolism, we discuss recent developments of metabolic effects on chromatin modifications and structure, as well as consequences on gene regulation.


Asunto(s)
Cromatina/metabolismo , Epigénesis Genética/genética , Metionina/metabolismo , Cromatina/química , ADN/química , Ingestión de Alimentos , Regulación de la Expresión Génica , Código de Histonas , Humanos , Metionina/química , Conformación Molecular , Nucleosomas/metabolismo , Inanición , Estrés Fisiológico
11.
Cell Res ; 31(6): 664-683, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33432115

RESUMEN

Fundamental processes such as ribosomal RNA synthesis and chromatin remodeling take place in the nucleolus, which is hyperactive in fast-proliferating cells. The sophisticated regulatory mechanism underlying the dynamic nucleolar structure and functions is yet to be fully explored. The present study uncovers the mutual functional dependency between a previously uncharacterized human long non-coding RNA, which we renamed LETN, and a key nucleolar protein, NPM1. Specifically, being upregulated in multiple types of cancer, LETN resides in the nucleolus via direct binding with NPM1. LETN plays a critical role in facilitating the formation of NPM1 pentamers, which are essential building blocks of the nucleolar granular component and control the nucleolar functions. Repression of LETN or NPM1 led to similar and profound changes of the nucleolar morphology and arrest of the nucleolar functions, which led to proliferation inhibition of human cancer cells and neural progenitor cells. Interestingly, this inter-dependency between LETN and NPM1 is associated with the evolutionarily new variations of NPM1 and the coincidental emergence of LETN in higher primates. We propose that this human-specific protein-lncRNA axis renders an additional yet critical layer of regulation with high physiological relevance in both cancerous and normal developmental processes that require hyperactive nucleoli.


Asunto(s)
ARN Largo no Codificante , Animales , Nucléolo Celular , Proliferación Celular , Proteínas Nucleares/genética , Nucleofosmina , ARN Largo no Codificante/genética
12.
Nat Immunol ; 21(12): 1540-1551, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33020660

RESUMEN

The metabolic challenges present in tumors attenuate the metabolic fitness and antitumor activity of tumor-infiltrating T lymphocytes (TILs). However, it remains unclear whether persistent metabolic insufficiency can imprint permanent T cell dysfunction. We found that TILs accumulated depolarized mitochondria as a result of decreased mitophagy activity and displayed functional, transcriptomic and epigenetic characteristics of terminally exhausted T cells. Mechanistically, reduced mitochondrial fitness in TILs was induced by the coordination of T cell receptor stimulation, microenvironmental stressors and PD-1 signaling. Enforced accumulation of depolarized mitochondria with pharmacological inhibitors induced epigenetic reprogramming toward terminal exhaustion, indicating that mitochondrial deregulation caused T cell exhaustion. Furthermore, supplementation with nicotinamide riboside enhanced T cell mitochondrial fitness and improved responsiveness to anti-PD-1 treatment. Together, our results reveal insights into how mitochondrial dynamics and quality orchestrate T cell antitumor responses and commitment to the exhaustion program.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Recuento de Linfocitos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Dinámicas Mitocondriales/inmunología , Biomarcadores , Epigénesis Genética , Epigenómica , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/inmunología , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Mitofagia , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Niacinamida/farmacología , Receptor de Muerte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Estrés Fisiológico , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
13.
BMC Bioinformatics ; 21(1): 340, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32738892

RESUMEN

BACKGROUND: Ribosome profiling has been widely used for studies of translation under a large variety of cellular and physiological contexts. Many of these studies have greatly benefitted from a series of data-mining tools designed for dissection of the translatome from different aspects. However, as the studies of translation advance quickly, the current toolbox still falls in short, and more specialized tools are in urgent need for deeper and more efficient mining of the important and new features of the translation landscapes. RESULTS: Here, we present RiboMiner, a bioinformatics toolset for mining of multi-dimensional features of the translatome with ribosome profiling data. RiboMiner performs extensive quality assessment of the data and integrates a spectrum of tools for various metagene analyses of the ribosome footprints and for detailed analyses of multiple features related to translation regulation. Visualizations of all the results are available. Many of these analyses have not been provided by previous methods. RiboMiner is highly flexible, as the pipeline could be easily adapted and customized for different scopes and targets of the studies. CONCLUSIONS: Applications of RiboMiner on two published datasets did not only reproduced the main results reported before, but also generated novel insights into the translation regulation processes. Therefore, being complementary to the current tools, RiboMiner could be a valuable resource for dissections of the translation landscapes and the translation regulations by mining the ribosome profiling data more comprehensively and with higher resolution. RiboMiner is freely available at https://github.com/xryanglab/RiboMiner and https://pypi.org/project/RiboMiner .


Asunto(s)
Biología Computacional/métodos , Biosíntesis de Proteínas , Ribosomas/metabolismo , Programas Informáticos , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Aminoácidos/genética , Codón/genética , Análisis de Datos , Minería de Datos
14.
Oncoimmunology ; 9(1): 1726556, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32117592

RESUMEN

The metabolism of both cancer and immune cells in the tumor microenvironment (TME) is poorly understood since most studies have focused on analysis in bulk samples and ex vivo cell culture models. Our recent analyses of single-cell RNA sequencing data suggest that the metabolic features of single cells within TME differ greatly from those of the bulk measurements. Here, we discuss some key findings about metabolism in cancer and immune cells and discuss possible relevance to immunotherapy.


Asunto(s)
Neoplasias , Análisis de la Célula Individual , Humanos , Inmunoterapia , Neoplasias/terapia , Análisis de Secuencia de ARN , Microambiente Tumoral
15.
Water Res ; 175: 115684, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32171099

RESUMEN

Photocatalysis provides a "green" strategy to produce the clean energy of H2. However, the realization of efficient H2 production is usually accomplished by the consumption of electron donors, which are costly energy carriers themselves. Here, we attempted to utilize the naturally abundant humic acid (HA), a representative natural organic matter (NOM), as the source of electron donor in a cascading oxic-anoxic photocatalytic system. Results showed that degradation of HA and remarkable H2 yield (1660.9 µmol g-1 h-1 at optimal condition) were obtained successively, whereas the anoxic photocatalytic treatment of pristine HA did not improve H2 yield but substantially eliminated the H2 production and HA degradation efficiency. These phenomena suggested the preoxidation process played a vital role in counteracting the detrimental effect of HA on photocatalytic H2 production. Electrochemical measurement indicated that the preoxidized HA harbored more redox-active moieties than the untreated HA and thus leading to a higher photo-induced charge carrier separation efficiency. A variety of advanced spectroscopic analyses revealed that the photocatalytic oxic pre-treatment resulted in breakdown of chemically inert, electron mediating and chromophoric aromatic macrostructure of HA to form smaller sized oxygenated organic intermediates. These intermediates were more nucleophilic than the pristine HA and acted as sacrificial reagent in the subsequent anoxic process for boosting H2 production. This study showcases an energy recovering water remediation process and paves the way for the design of novel photocatalytic technologies for environmental application.


Asunto(s)
Sustancias Húmicas , Purificación del Agua , Electrones , Hidrógeno , Oxidación-Reducción
16.
Nat Cell Biol ; 22(3): 310-320, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32144411

RESUMEN

Although metastasis remains the cause of most cancer-related mortality, mechanisms governing seeding in distal tissues are poorly understood. Here, we establish a robust method for the identification of global transcriptomic changes in rare metastatic cells during seeding using single-cell RNA sequencing and patient-derived-xenograft models of breast cancer. We find that both primary tumours and micrometastases display transcriptional heterogeneity but micrometastases harbour a distinct transcriptome program conserved across patient-derived-xenograft models that is highly predictive of poor survival of patients. Pathway analysis revealed mitochondrial oxidative phosphorylation as the top pathway upregulated in micrometastases, in contrast to higher levels of glycolytic enzymes in primary tumour cells, which we corroborated by flow cytometric and metabolomic analyses. Pharmacological inhibition of oxidative phosphorylation dramatically attenuated metastatic seeding in the lungs, which demonstrates the functional importance of oxidative phosphorylation in metastasis and highlights its potential as a therapeutic target to prevent metastatic spread in patients with breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Transcriptoma , Animales , Neoplasias de la Mama/metabolismo , Metabolismo Energético , Femenino , Humanos , Ratones Endogámicos NOD , Ratones SCID , Mitocondrias/metabolismo , Metástasis de la Neoplasia , Fosforilación Oxidativa , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcripción Genética
17.
Comput Math Methods Med ; 2019: 4830914, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31885681

RESUMEN

In recent years, we have seen more and more interest in the field of medical images and shape comparison motivated by the latest advances in microcomputed tomography (µCT) acquisition, modelling, and visualization technologies. Usually, biologists need to evaluate the effect of different root canal preparation systems. Current root canal preparation evaluation methods are based on the volume difference, area difference, and transportation of two root canals before and after treatment. The purpose of root canal preparation is to minimize the volume difference and ensure the complete removal of the smear layer. Previous methods can reflect some general geometric differences, but they are not enough to evaluate the quality of root canal shape. To solve this problem, we proposed a novel root canal evaluation method based on spectrum and eigenfunctions of Steklov operators, which can be served as a better alternative to current methods in root canal preparation evaluation. Firstly, the ideal root canal model was simulated according to the root canal model before and after preparation. Secondly, the Steklov spectrum of the two models was calculated. Thirdly, based on the spectrum and the histogram of the Gaussian curvature on the surface, the weight of each eigenvalue was computed. Therefore, the Steklov spectrum distance (SSD), which measures shape difference between the root canals, was defined. Finally, the calculation method that quantifies the root canal preparation effect of root canals was obtained. Through experiments, our method manifested high robustness and accuracy compared with existing state-of-the-art approaches. It also demonstrates the significance of our algorithm's advantages on a variety of challenging root canals through result comparison with counterpart methods.


Asunto(s)
Cavidad Pulpar/diagnóstico por imagen , Preparación del Conducto Radicular/estadística & datos numéricos , Algoritmos , Biología Computacional , Simulación por Computador , Humanos , Imagenología Tridimensional , Interpretación de Imagen Radiográfica Asistida por Computador , Microtomografía por Rayos X
18.
Nat Commun ; 10(1): 3763, 2019 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-31434891

RESUMEN

The tumor milieu consists of numerous cell types each existing in a different environment. However, a characterization of metabolic heterogeneity at single-cell resolution is not established. Here, we develop a computational pipeline to study metabolic programs in single cells. In two representative human cancers, melanoma and head and neck, we apply this algorithm to define the intratumor metabolic landscape. We report an overall discordance between analyses of single cells and those of bulk tumors with higher metabolic activity in malignant cells than previously appreciated. Variation in mitochondrial programs is found to be the major contributor to metabolic heterogeneity. Surprisingly, the expression of both glycolytic and mitochondrial programs strongly correlates with hypoxia in all cell types. Immune and stromal cells could also be distinguished by their metabolic features. Taken together this analysis establishes a computational framework for characterizing metabolism using single cell expression data and defines principles of the tumor microenvironment.


Asunto(s)
Neoplasias/metabolismo , Microambiente Tumoral/fisiología , Algoritmos , Línea Celular Tumoral , Reprogramación Celular , Regulación Neoplásica de la Expresión Génica , Genes Relacionados con las Neoplasias , Glucólisis , Humanos , Melanoma/metabolismo , Mitocondrias/metabolismo , Neoplasias/genética , Células del Estroma/metabolismo , Transcriptoma , Microambiente Tumoral/genética
19.
Theranostics ; 9(14): 4141-4155, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31281537

RESUMEN

Despite the critical position of translation in the multilevel gene expression regulation program, high-resolution and genome-wide view of the landscape of RNA translation in solid tumors is still limited. Methods: With a ribosome profiling procedure optimized for solid tissue samples, we profiled the translatomes of liver tumors and their adjacent noncancerous normal liver tissues from 10 patients with hepatocellular carcinoma (HCC). A set of bioinformatics tools was then applied to these data for the mining of novel insights into the translation shifts in HCC. Results: This is the first translatome data resource for dissecting dysregulated translation in HCC at the sub-codon resolution. Based on our data, quantitative comparisons of mRNA translation rates yielded the genes and processes that were subjected to patient specific or universal dysregulations of translation efficiencies in tumors. For example, multiple proteins involved in extracellular matrix organization exhibited significant translational upregulation in tumors. We then experimentally validated the tumor-promoting functions of two such genes as examples: AGRN and VWA1. In addition, the data was also used for de novo annotation of the translatomes in tumors and normal tissues, including multiple types of novel non-canonical small ORFs, which would be a resource for further functional studies. Conclusions: The present study generates the first survey of the HCC translatome with ribosome profiling, which is an insightful data resource for dissecting the translatome shift in liver cancer, at sub-codon resolution.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Animales , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Hepáticas/genética , Masculino , Biosíntesis de Proteínas/genética , Biosíntesis de Proteínas/fisiología , Ribosomas/metabolismo
20.
Cell Rep ; 27(8): 2335-2353.e6, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31116980

RESUMEN

Zinc-finger E-box binding homeobox 1 (Zeb1) is a key regulator of epithelial-mesenchymal transition and cancer metastasis. Mutation of ZEB1 is associated with human diseases and defective brain development. Here we show that downregulation of Zeb1 expression in embryonic cortical neural progenitor cells (NPCs) is necessary for proper neuronal differentiation and migration. Overexpression of Zeb1 during neuronal differentiation, when its expression normally declines, blocks NPC lineage progression and disrupts multipolar-to-bipolar transition of differentiating neurons, leading to severe migration defects and subcortical heterotopia bands at postnatal stages. ZEB1 regulates a cohort of genes involved in cell differentiation and migration, including Neurod1 and Pard6b. The interaction between ZEB1 and CTBP2 in the embryonic cerebral cortex is required for ZEB1 to elicit its effect on the multipolar-to-bipolar transition, but not its suppression of Neurod1. These findings provide insights into understanding the complexity of transcriptional regulation during neuronal differentiation.


Asunto(s)
Oxidorreductasas de Alcohol/metabolismo , Proteínas Co-Represoras/metabolismo , Neocórtex/crecimiento & desarrollo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Animales , Diferenciación Celular , Línea Celular Tumoral , Movimiento Celular , Humanos , Ratones
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