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1.
Cell ; 186(9): 1968-1984.e20, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37040760

RESUMEN

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.


Asunto(s)
Enfermedades Metabólicas , Enfermedad del Hígado Graso no Alcohólico , Animales , Humanos , Masculino , Ratones , N-Metiltransferasa de Histona-Lisina/genética , Hígado/metabolismo , Mosaicismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo
2.
Trends Genet ; 37(5): 403-404, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33541711

RESUMEN

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.


Asunto(s)
Células Madre Pluripotentes Inducidas , Organoides , Humanos , Hígado , Transcriptoma
3.
Nature ; 532(7599): 329-33, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27027282

RESUMEN

It has been widely accepted that 5-methylcytosine is the only form of DNA methylation in mammalian genomes. Here we identify N(6)-methyladenine as another form of DNA modification in mouse embryonic stem cells. Alkbh1 encodes a demethylase for N(6)-methyladenine. An increase of N(6)-methyladenine levels in Alkbh1-deficient cells leads to transcriptional silencing. N(6)-methyladenine deposition is inversely correlated with the evolutionary age of LINE-1 transposons; its deposition is strongly enriched at young (<1.5 million years old) but not old (>6 million years old) L1 elements. The deposition of N(6)-methyladenine correlates with epigenetic silencing of such LINE-1 transposons, together with their neighbouring enhancers and genes, thereby resisting the gene activation signals during embryonic stem cell differentiation. As young full-length LINE-1 transposons are strongly enriched on the X chromosome, genes located on the X chromosome are also silenced. Thus, N(6)-methyladenine developed a new role in epigenetic silencing in mammalian evolution distinct from its role in gene activation in other organisms. Our results demonstrate that N(6)-methyladenine constitutes a crucial component of the epigenetic regulation repertoire in mammalian genomes.


Asunto(s)
Adenina/análogos & derivados , Metilación de ADN , Epigénesis Genética/genética , Células Madre Embrionarias de Ratones/metabolismo , Adenina/metabolismo , Histona H2a Dioxigenasa, Homólogo 1 de AlkB , Animales , Diferenciación Celular/genética , Elementos Transponibles de ADN/genética , ADN-(Sitio Apurínico o Apirimidínico) Liasa/deficiencia , ADN-(Sitio Apurínico o Apirimidínico) Liasa/genética , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Elementos de Facilitación Genéticos/genética , Evolución Molecular , Silenciador del Gen , Elementos de Nucleótido Esparcido Largo/genética , Mamíferos/genética , Ratones , Células Madre Embrionarias de Ratones/citología , Regulación hacia Arriba/genética , Cromosoma X/genética , Cromosoma X/metabolismo
4.
Genome Res ; 28(7): 1067-1078, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29764913

RESUMEN

N6-Methyladenine (m6dA) has been discovered as a novel form of DNA methylation prevalent in eukaryotes; however, methods for high-resolution mapping of m6dA events are still lacking. Single-molecule real-time (SMRT) sequencing has enabled the detection of m6dA events at single-nucleotide resolution in prokaryotic genomes, but its application to detecting m6dA in eukaryotic genomes has not been rigorously examined. Herein, we identified unique characteristics of eukaryotic m6dA methylomes that fundamentally differ from those of prokaryotes. Based on these differences, we describe the first approach for mapping m6dA events using SMRT sequencing specifically designed for the study of eukaryotic genomes and provide appropriate strategies for designing experiments and carrying out sequencing in future studies. We apply the novel approach to study two eukaryotic genomes. For green algae, we construct the first complete genome-wide map of m6dA at single-nucleotide and single-molecule resolution. For human lymphoblastoid cells (hLCLs), it was necessary to integrate SMRT sequencing data with independent sequencing data. The joint analyses suggest putative m6dA events are enriched in the promoters of young full-length LINE-1 elements (L1s), but call for validation by additional methods. These analyses demonstrate a general method for rigorous mapping and characterization of m6dA events in eukaryotic genomes.


Asunto(s)
Eucariontes/genética , Genoma/genética , Línea Celular , Mapeo Cromosómico/métodos , Metilación de ADN/genética , Humanos , Células Procariotas/metabolismo , Regiones Promotoras Genéticas/genética , Análisis de Secuencia de ADN/métodos
5.
BMC Genomics ; 21(1): 229, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171242

RESUMEN

BACKGROUND: Gene expression regulators identified in transcriptome profiling experiments may serve as ideal targets for genetic manipulations in farm animals. RESULTS: In this study, we developed a gene expression profile of 76,000+ unique transcripts for 224 porcine samples from 28 tissues collected from 32 animals using Super deepSAGE technology. Excellent sequencing depth was achieved for each multiplexed library, and replicated samples from the same tissues clustered together, demonstrating the high quality of Super deepSAGE data. Comparison with previous research indicated that our results not only have good reproducibility but also have greatly extended the coverage of the sample types as well as the number of genes. Clustering analysis revealed ten groups of genes showing distinct expression patterns among these samples. Our analysis of over-represented binding motifs identified 41 regulators, and we demonstrated a potential application of this dataset in infectious diseases and immune biology research by identifying an LPS-dependent transcription factor, runt-related transcription factor 1 (RUNX1), in peripheral blood mononuclear cells (PBMCs). The selected genes are specifically responsible for the transcription of toll-like receptor 2 (TLR2), lymphocyte-specific protein tyrosine kinase (LCK), and vav1 oncogene (VAV1), which belong to the T and B cell signaling pathways. CONCLUSIONS: The Super deepSAGE technology and tissue-differential expression profiles are valuable resources for investigating the porcine gene expression regulation. The identified RUNX1 target genes belong to the T and B cell signaling pathways, making them novel potential targets for the diagnosis and therapy of bacterial infections and other immune disorders.


Asunto(s)
Biología Computacional/métodos , Perfilación de la Expresión Génica/veterinaria , Redes Reguladoras de Genes , Sus scrofa/genética , Animales , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Regulación de la Expresión Génica , Leucocitos Mononucleares/química , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/genética , Proteínas Proto-Oncogénicas c-vav/genética , Reproducibilidad de los Resultados , Porcinos , Distribución Tisular , Receptor Toll-Like 2/genética
6.
Bioinformatics ; 35(1): 160-163, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30010968

RESUMEN

Summary: level data of GWAS becomes increasingly important in post-GWAS data mining. Here, we present GIGSEA (Genotype Imputed Gene Set Enrichment Analysis), a novel method that uses GWAS summary statistics and eQTL to infer differential gene expression and interrogate gene set enrichment for the trait-associated SNPs. By incorporating empirical eQTL of the disease relevant tissue, GIGSEA naturally accounts for factors such as gene size, gene boundary, SNP distal regulation and multiple-marker regulation. The weighted linear regression model was used to perform the enrichment test, properly adjusting for imputation accuracy, model incompleteness and redundancy in different gene sets. The significance level of enrichment is assessed by the permutation test, where matrix operation was employed to dramatically improve computation speed. GIGSEA has appropriate type I error rates, and discovers the plausible biological findings on the real data set. Availability and implementation: GIGSEA is implemented in R, and freely available at www.github.com/zhushijia/GIGSEA. Supplementary information: Supplementary data are available at Bioinformatics online.


Asunto(s)
Estudio de Asociación del Genoma Completo , Genotipo , Polimorfismo de Nucleótido Simple , Programas Informáticos , Biología Computacional , Modelos Lineales , Sitios de Carácter Cuantitativo
7.
Bioinformatics ; 34(14): 2341-2348, 2018 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-29509873

RESUMEN

Motivation: For many traits, causal loci uncovered by genetic mapping studies explain only a minority of the heritable contribution to trait variation. Multiple explanations for this 'missing heritability' have been proposed. Single nucleotide polymorphism (SNP)-SNP interaction (epistasis), as one of the compelling models, has been widely studied. However, the genome-wide scan of epistasis, especially for quantitative traits, poses huge computational challenges. Moreover, covariate adjustment is largely ignored in epistasis analysis due to the massive extra computational undertaking. Results: In the current study, we found striking differences among epistasis models using both simulation data and real biological data, suggesting that not only can covariate adjustment remove confounding bias, it can also improve power. Furthermore, we derived mathematical formulas, which enable the exhaustive epistasis scan together with full covariate adjustment to be expressed in terms of large matrix operation, therefore substantially improving the computational efficiency (∼104× faster than existing methods). We call the new method MatrixEpistasis. With MatrixEpistasis, we re-analyze a large real yeast dataset comprising 11 623 SNPs, 1008 segregants and 46 quantitative traits with covariates fully adjusted and detect thousands of novel putative epistasis with P-values < 1.48e-10. Availability and implementation: The method is implemented in R and available at https://github.com/fanglab/MatrixEpistasis. Supplementary information: Supplementary data are available at Bioinformatics online.


Asunto(s)
Epistasis Genética , Estudio de Asociación del Genoma Completo/métodos , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Programas Informáticos , Humanos
8.
PLoS Genet ; 11(11): e1005666, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26588462

RESUMEN

DNA methylation is a key epigenetic regulator in all domains of life, yet the effects of most bacterial DNA methyltransferases on cellular processes are largely undefined. Here, we used diverse techniques, including bisulfite sequencing, transcriptomics, and transposon insertion site sequencing to extensively characterize a 5-methylcytosine (5mC) methyltransferase, VchM, in the cholera pathogen, Vibrio cholerae. We have comprehensively defined VchM's DNA targets, its genetic interactions and the gene networks that it regulates. Although VchM is a relatively new component of the V. cholerae genome, it is required for optimal V. cholerae growth in vitro and during infection. Unexpectedly, the usually essential σE cell envelope stress pathway is dispensable in ∆vchM V. cholerae, likely due to its lower activation in this mutant and the capacity for VchM methylation to limit expression of some cell envelope modifying genes. Our work illuminates how an acquired DNA methyltransferase can become integrated within complex cell circuits to control critical housekeeping processes.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/metabolismo , Vibrio cholerae/enzimología , Metilación de ADN , ADN Bacteriano/metabolismo , Redes Reguladoras de Genes , Estrés Fisiológico , Vibrio cholerae/genética , Vibrio cholerae/crecimiento & desarrollo , Vibrio cholerae/metabolismo
9.
PLoS Genet ; 11(12): e1005739, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26657207

RESUMEN

[This corrects the article DOI: 10.1371/journal.pgen.1005666.].

10.
Mitochondrial DNA B Resour ; 9(6): 734-737, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887217

RESUMEN

This study presents the initial sequencing and characterization of the complete mitochondrial genome (mitogenome) of Hyalinocerus flavoscutatus, making the first comprehensive exploration of the mitogenome in the Hyalinocerus. Utilizing next-generation sequencing techniques, we identified a circular DNA molecule spanning 15,307 bp. The mitogenome comprises 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a primary non-coding region. Maximum likelihood phylogenetic evaluation, based on 13 protein-coding genes and two ribosomal RNA genes, robustly supports H. flavoscutatus as the basal group within Idiocerini. This research unveils valuable insights into the mitogenome of H. flavoscutatus and enhances our understanding of phylogenetic placement within the broader context of related tribes.

11.
bioRxiv ; 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38187541

RESUMEN

In spot-based spatial transcriptomics, spots that are of the same size and printed at the fixed location cannot precisely capture the actual randomly located single cells, therefore failing to profile the transcriptome at the single-cell level. The current studies primarily focused on enhancing the spot resolution in size via computational imputation or technical improvement, however, they largely overlooked that single-cell resolution, i.e., resolution in cellular or even smaller size, does not equal single-cell level. Using both real and simulated spatial transcriptomics data, we demonstrated that even the high-resolution spatial transcriptomics still has a large number of spots partially covering multiple cells simultaneously, revealing the intrinsic non-single-cell level of spot-based spatial transcriptomics regardless of spot size. To this end, we present STIE, an EM algorithm that aligns the spatial transcriptome to its matched histology image-based nuclear morphology and recovers missing cells from up to ~70% gap area between spots via the nuclear morphological similarity and neighborhood information, thereby achieving the real single-cell level and whole-slide scale deconvolution/convolution and clustering for both low- and high-resolution spots. On both real and simulation spatial transcriptomics data, STIE characterizes the cell-type specific gene expression variation and demonstrates the outperforming concordance with the single-cell RNAseq-derived cell type transcriptomic signatures compared to the other spot- and subspot-level methods. Furthermore, STIE enabled us to gain novel insights that failed to be revealed by the existing methods due to the lack of single-cell level, for instance, lower actual spot resolution than its reported spot size, the additional contribution of cellular morphology to cell typing beyond transcriptome, unbiased evaluation of cell type colocalization, superior power of high-resolution spot in distinguishing nuanced cell types, and spatially resolved cell-cell interactions at the single-cell level other than spot level. The STIE code is publicly available as an R package at https://github.com/zhushijia/STIE.

12.
bioRxiv ; 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36993727

RESUMEN

Somatic mutations in non-malignant tissues accumulate with age and insult, but whether these mutations are adaptive on the cellular or organismal levels is unclear. To interrogate mutations found in human metabolic disease, we performed lineage tracing in mice harboring somatic mosaicism subjected to non-alcoholic 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 Bcl6, Tbx3, or Smyd2 resulted in protection against NASH. Selection for clonal fitness in mouse and human livers identifies pathways that regulate metabolic disease. Highlights: Mosaic Mboat7 mutations that increase lipotoxicity lead to clonal disappearance in NASH. In vivo screening can identify genes that alter hepatocyte fitness in NASH. Mosaic Gpam mutations are positively selected due to reduced lipogenesis. In vivo screening of transcription factors and epifactors identified new therapeutic targets in NASH.

13.
Cancer Discov ; 13(12): 2584-2609, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-37676710

RESUMEN

Signaling rewiring allows tumors to survive therapy. Here we show that the decrease of the master regulator microphthalmia transcription factor (MITF) in lethal prostate cancer unleashes eukaryotic initiation factor 3B (eIF3B)-dependent translation reprogramming of key mRNAs conferring resistance to androgen deprivation therapy (ADT) and promoting immune evasion. Mechanistically, MITF represses through direct promoter binding eIF3B, which in turn regulates the translation of specific mRNAs. Genome-wide eIF3B enhanced cross-linking immunoprecipitation sequencing (eCLIP-seq) showed specialized binding to a UC-rich motif present in subsets of 5' untranslated regions. Indeed, translation of the androgen receptor and major histocompatibility complex I (MHC-I) through this motif is sensitive to eIF3B amount. Notably, pharmacologic targeting of eIF3B-dependent translation in preclinical models sensitizes prostate cancer to ADT and anti-PD-1 therapy. These findings uncover a hidden connection between transcriptional and translational rewiring promoting therapy-refractory lethal prostate cancer and provide a druggable mechanism that may transcend into effective combined therapeutic strategies. SIGNIFICANCE: Our study shows that specialized eIF3B-dependent translation of specific mRNAs released upon downregulation of the master transcription factor MITF confers castration resistance and immune evasion in lethal prostate cancer. Pharmacologic targeting of this mechanism delays castration resistance and increases immune-checkpoint efficacy. This article is featured in Selected Articles from This Issue, p. 2489.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Masculino , Humanos , Factores de Transcripción , Antagonistas de Andrógenos/farmacología , Antagonistas de Andrógenos/uso terapéutico , Evasión Inmune , Receptores Androgénicos/genética , Castración , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/patología
14.
Mol Biotechnol ; 64(1): 9-16, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34427871

RESUMEN

Since the discovery of microRNAs (miRNAs) as a class of important regulatory molecules, miRNAs are involved in the occurrence and development of tumors. In this paper, we aimed to identify the role of miR-1274a in non-small cell lung cancer (NSCLC). The miR-1274a expression levels in four NSCLC cells and tissues from 125 patients were determined by qRT-PCR assays. Kaplan-Meier survival curves and Cox regression analysis were used to examine the prognostic significance of miR-1274a in NSCLC patients. The CCK-8 and Transwell assays were performed to evaluate the cell proliferation, invasion, and migration ability of NSCLC cells. The miR-1274a expression levels were significantly higher in NSCLC tissues than in adjacent normal tissues, and overexpression of miR-1274a had a poor prognosis in NSCLC patients. Functional studies in two NSCLC cell lines have shown that overexpression of miR-1274a could promote cell proliferation, migration, and invasion. miR-1274a expression levels are upregulated in NSCLC tissues, and a high expression is associated with a poor prognosis in patients with NSCLC. Moreover, miR-1274a promotes cell proliferation, migration, and invasion. Based on our findings, miR-1274a may act as a tumor miRNA in the occurrence and development of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , MicroARNs/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Regulación hacia Arriba/genética
15.
Cell Mol Gastroenterol Hepatol ; 13(5): 1483-1509, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35093588

RESUMEN

BACKGROUND & AIMS: During liver fibrosis, tissue repair mechanisms replace necrotic tissue with highly stabilized extracellular matrix proteins. Extracellular matrix stabilization influences the speed of tissue recovery. Here, we studied the expression and function of peroxidasin (PXDN), a peroxidase that uses hydrogen peroxide to cross-link collagen IV during liver fibrosis progression and regression. METHODS: Mouse models of liver fibrosis and cirrhosis patients were analyzed for the expression of PXDN in liver and serum. Pxdn-/- and Pxdn+/+ mice were either treated with carbon tetrachloride for 6 weeks to generate toxin-induced fibrosis or fed with a choline-deficient L-amino acid-defined high-fat diet for 16 weeks to create nonalcoholic fatty liver disease fibrosis. Liver histology, quantitative real-time polymerase chain reaction, collagen content, flowcytometry and immunostaining of immune cells, RNA-sequencing, and liver function tests were analyzed. In vivo imaging of liver reactive oxygen species (ROS) was performed using a redox-active iron complex, Fe-PyC3A. RESULTS: In human and mouse cirrhotic tissue, PXDN is expressed by stellate cells and is secreted into fibrotic areas. In patients with nonalcoholic fatty liver disease, serum levels of PXDN increased significantly. In both mouse models of liver fibrosis, PXDN deficiency resulted in elevated monocyte and pro-fibrolysis macrophage recruitment into fibrotic bands and caused decreased accumulation of cross-linked collagens. In Pxdn-/- mice, collagen fibers were loosely organized, an atypical phenotype that is reversible upon macrophage depletion. Elevated ROS in Pxdn-/- livers was observed, which can result in activation of hypoxic signaling cascades and may affect signaling pathways involved in macrophage polarization such as TNF-a via NF-kB. Fibrosis resolution in Pxdn-/- mice was associated with significant decrease in collagen content and improved liver function. CONCLUSION: PXDN deficiency is associated with increased ROS levels and a hypoxic liver microenvironment that can regulate recruitment and programming of pro-resolution macrophages. Our data implicate the importance of the liver microenvironment in macrophage programming during liver fibrosis and suggest a novel pathway that is involved in the resolution of scar tissue.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Peroxidasas , Animales , Colágeno/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Fibrosis , Humanos , Cirrosis Hepática/patología , Macrófagos/metabolismo , Ratones , Enfermedad del Hígado Graso no Alcohólico/patología , Peroxidasas/genética , Especies Reactivas de Oxígeno/metabolismo
16.
JCI Insight ; 7(13)2022 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-35801591

RESUMEN

Hepatocellular carcinoma (HCC) is a leading cause of death among cirrhotic patients, for which chemopreventive strategies are lacking. Recently, we developed a simple human cell-based system modeling a clinical prognostic liver signature (PLS) predicting liver disease progression and HCC risk. In a previous study, we applied our cell-based system for drug discovery and identified captopril, an approved angiotensin converting enzyme (ACE) inhibitor, as a candidate compound for HCC chemoprevention. Here, we explored ACE as a therapeutic target for HCC chemoprevention. Captopril reduced liver fibrosis and effectively prevented liver disease progression toward HCC development in a diethylnitrosamine (DEN) rat cirrhosis model and a diet-based rat model for nonalcoholic steatohepatitis-induced (NASH-induced) hepatocarcinogenesis. RNA-Seq analysis of cirrhotic rat liver tissues uncovered that captopril suppressed the expression of pathways mediating fibrogenesis, inflammation, and carcinogenesis, including epidermal growth factor receptor (EGFR) signaling. Mechanistic data in liver disease models uncovered a cross-activation of the EGFR pathway by angiotensin. Corroborating the clinical translatability of the approach, captopril significantly reversed the HCC high-risk status of the PLS in liver tissues of patients with advanced fibrosis. Captopril effectively prevents fibrotic liver disease progression toward HCC development in preclinical models and is a generic and safe candidate drug for HCC chemoprevention.


Asunto(s)
Captopril , Carcinoma Hepatocelular , Neoplasias Hepáticas , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Captopril/farmacología , Captopril/uso terapéutico , Carcinogénesis , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/prevención & control , Quimioprevención , Progresión de la Enfermedad , Receptores ErbB/metabolismo , Cirrosis Hepática/prevención & control , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/prevención & control , Peptidil-Dipeptidasa A/metabolismo , Ratas , Activación Transcripcional
17.
Sci Transl Med ; 14(650): eabo4474, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35731891

RESUMEN

Prediction of hepatocellular carcinoma (HCC) risk is an urgent unmet need in patients with nonalcoholic fatty liver disease (NAFLD). In cohorts of 409 patients with NAFLD from multiple global regions, we defined and validated hepatic transcriptome and serum secretome signatures predictive of long-term HCC risk in patients with NAFLD. A 133-gene signature, prognostic liver signature (PLS)-NAFLD, predicted incident HCC over up to 15 years of longitudinal observation. High-risk PLS-NAFLD was associated with IDO1+ dendritic cells and dysfunctional CD8+ T cells in fibrotic portal tracts along with impaired metabolic regulators. PLS-NAFLD was validated in independent cohorts of patients with NAFLD who were HCC naïve (HCC incidence rates at 15 years were 22.7 and 0% in high- and low-risk patients, respectively) or HCC experienced (de novo HCC recurrence rates at 5 years were 71.8 and 42.9% in high- and low-risk patients, respectively). PLS-NAFLD was bioinformatically translated into a four-protein secretome signature, PLSec-NAFLD, which was validated in an independent cohort of HCC-naïve patients with NAFLD and cirrhosis (HCC incidence rates at 15 years were 37.6 and 0% in high- and low-risk patients, respectively). Combination of PLSec-NAFLD with our previously defined etiology-agnostic PLSec-AFP yielded improved HCC risk stratification. PLS-NAFLD was modified by bariatric surgery, lipophilic statin, and IDO1 inhibitor, suggesting that the signature can be used for drug discovery and as a surrogate end point in HCC chemoprevention clinical trials. Collectively, PLS/PLSec-NAFLD may enable NAFLD-specific HCC risk prediction and facilitate clinical translation of NAFLD-directed HCC chemoprevention.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Linfocitos T CD8-positivos , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/genética , Factores de Riesgo
18.
BMC Genomics ; 12: 329, 2011 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-21702984

RESUMEN

BACKGROUND: MicroRNAs (miRNAs) are non-coding RNAs with important roles in regulating gene expression. Recent studies indicate that transcription and cleavage of miRNA are coupled, and that chromatin structure may influence miRNA transcription. However, little is known about the relationship between the chromatin structure and cleavage of pre-miRNA from pri-miRNA. RESULTS: By analysis of genome-wide nucleosome positioning data sets from human and Caenorhabditis elegans (C. elegans), we found an enrichment of positioned nucleosome on pre-miRNA genomic sequences, which is highly correlated with GC content within pre-miRNA. In addition, obvious enrichments of three histone modifications (H2BK5me1, H3K36me3 and H4K20me1) as well as RNA Polymerase II (RNAPII) were observed on pre-miRNA genomic sequences corresponding to the active-promoter miRNAs and expressed miRNAs. CONCLUSION: Our results revealed the chromatin structure characteristics of pre-miRNA genomic sequences, and implied potential mechanisms that can recognize these characteristics, thus improving pre-miRNA cleavage.


Asunto(s)
Cromatina/química , Genoma , MicroARNs/genética , Precursores del ARN/genética , Animales , Caenorhabditis elegans/genética , Perfilación de la Expresión Génica , Histonas/genética , Humanos , MicroARNs/metabolismo , Nucleosomas/genética , ARN Polimerasa II/genética , Precursores del ARN/metabolismo
19.
Med ; 2(7): 836-850.e10, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34318286

RESUMEN

BACKGROUND: Accurate non-invasive prediction of long-term hepatocellular carcinoma (HCC) risk in advanced liver fibrosis is urgently needed for cost-effective HCC screening; however, this currently remains an unmet need. METHODS: A serum-protein-based prognostic liver secretome signature (PLSec) was bioinformatically derived from previously validated hepatic transcriptome signatures and optimized in 79 patients with advanced liver fibrosis. We independently validated PLSec for HCC risk in 331 cirrhosis patients with mixed etiologies (validation set 1 [V1]) and thereafter developed a score with clinical prognostic variables. The score was then validated in two independent cohorts: validation set 2 (V2): 164 patients with advanced liver fibrosis due to hepatitis C virus (HCV) infection cured after direct-acting antiviral therapy; validation set 3 (V3): 146 patients with advanced liver fibrosis with successfully-treated HCC and cured HCV infection. FINDINGS: An 8-protein blood-based PLSec recapitulated transcriptome-based hepatic HCC risk status. In V1, PLSec was significantly associated with incident HCC risk (adjusted hazard ratio [aHR], 2.35; 95% confidence interval [CI], 1.30-4.23). A composite score with serum alpha-fetoprotein (PLSec-AFP) was defined in V1, and validated in V2 (adjusted odds ratio, 3.80 [95%CI, 1.66-8.66]) and V3 (aHR, 3.08 [95%CI, 1.78-5.31]; c-index, 0.74). PLSec-AFP outperformed AFP alone (Brier score, 0.165 vs. 0.186 in V2; 0.196 vs. 0.206 in V3, respectively). CONCLUSIONS: The blood-based PLSec-AFP can accurately stratify patients with advanced liver fibrosis for long-term HCC risk and thereby guide risk-based tailored HCC screening.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C Crónica , Hepatitis C , Neoplasias Hepáticas , Antivirales/uso terapéutico , Carcinoma Hepatocelular/diagnóstico , Hepacivirus/metabolismo , Hepatitis C/complicaciones , Hepatitis C Crónica/complicaciones , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/diagnóstico , Pronóstico , Secretoma , alfa-Fetoproteínas/metabolismo
20.
Nat Commun ; 12(1): 5525, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34535664

RESUMEN

Chronic liver disease and hepatocellular carcinoma (HCC) are life-threatening diseases with limited treatment options. The lack of clinically relevant/tractable experimental models hampers therapeutic discovery. Here, we develop a simple and robust human liver cell-based system modeling a clinical prognostic liver signature (PLS) predicting long-term liver disease progression toward HCC. Using the PLS as a readout, followed by validation in nonalcoholic steatohepatitis/fibrosis/HCC animal models and patient-derived liver spheroids, we identify nizatidine, a histamine receptor H2 (HRH2) blocker, for treatment of advanced liver disease and HCC chemoprevention. Moreover, perturbation studies combined with single cell RNA-Seq analyses of patient liver tissues uncover hepatocytes and HRH2+, CLEC5Ahigh, MARCOlow liver macrophages as potential nizatidine targets. The PLS model combined with single cell RNA-Seq of patient tissues enables discovery of urgently needed targets and therapeutics for treatment of advanced liver disease and cancer prevention.


Asunto(s)
Descubrimiento de Drogas , Hígado/patología , Modelos Biológicos , Animales , Carcinogénesis/patología , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Quimioprevención , Estudios de Cohortes , AMP Cíclico/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Hepacivirus/fisiología , Hepatitis C/genética , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Vigilancia Inmunológica/efectos de los fármacos , Inflamación/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones Noqueados , Nizatidina/farmacología , Pronóstico , Transducción de Señal/efectos de los fármacos , Transcriptoma/genética
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