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1.
Hepatology ; 77(2): 501-511, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35989577

RESUMEN

BACKGROUND AND AIMS: Porto-sinusoidal vascular disorder (PSVD) is a group of liver vascular diseases featuring lesions encompassing the portal venules and sinusoids unaccompanied by cirrhosis, irrespective of the presence/absence of portal hypertension. It can occur secondary to coagulation disorders or insult by toxic agents. However, the cause of PSVD remains unknown in most cases. Hereditary cases of PSVD are exceptionally rare, but they are of particular interest and may unveil genetic alterations and molecular mechanisms associated with the disease. APPROACH AND RESULTS: We performed genome sequencing of four patients and two healthy individuals of a large multigenerational Lebanese family with PSVD and identified a heterozygous deleterious variant (c.547C>T, p.R183W) of FCH and double SH3 domains 1 ( FCHSD1 ), an uncharacterized gene, in patients. This variant segregated with the disease, and its pattern of inheritance was suggestive of autosomal dominant with variable expressivity. RNA structural modelling of human FCHSD1 suggests that the C-to-T substitution at position 547, corresponding to FCHSD1R183W , may increase both messenger RNA (mRNA) and protein stability and its interaction with MTOR-associated protein, LST8 homolog, a key protein of the mechanistic target of rapamycin (mTOR pathway). These predictions were substantiated by biochemical analyses, which showed that FCHSD1R183W induced high FCHSD1 mRNA stability, overexpression of FCHSD1 protein, and an increase in mTORC1 activation. This human FCHSD1 variant was introduced into mice through CRISPR/Cas9 genome editing. Nine out of the 15 mice carrying the human FCHSD1R183W variant mimicked the phenotype of human PSVD, including splenomegaly and enlarged portal vein. CONCLUSIONS: Aberrant FCHSD1 structure and function leads to mTOR pathway overactivation and may cause PSVD.


Asunto(s)
Hipertensión Portal , Enfermedades Vasculares , Humanos , Ratones , Animales , Predisposición Genética a la Enfermedad , Familia Extendida , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Hipertensión Portal/metabolismo , Genómica
2.
Lancet Oncol ; 23(3): 341-352, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35150601

RESUMEN

BACKGROUND: Disparities in the genetic risk of cancer among various ancestry groups and populations remain poorly defined. This challenge is even more acute for Middle Eastern populations, where the paucity of genomic data could affect the clinical potential of cancer genetic risk profiling. We used data from the phase 1 cohort of the Qatar Genome Programme to investigate genetic variation in cancer-susceptibility genes in the Qatari population. METHODS: The Qatar Genome Programme generated high-coverage genome sequencing on DNA samples collected from 6142 native Qataris, stratified into six distinct ancestry groups: general Arab, Persian, Arabian Peninsula, Admixture Arab, African, and South Asian. In this population-based, cohort study, we evaluated the performance of polygenic risk scores for the most common cancers in Qatar (breast, prostate, and colorectal cancers). Polygenic risk scores were trained in The Cancer Genome Atlas (TCGA) dataset, and their distributions were subsequently applied to the six different genetic ancestry groups of the Qatari population. Rare deleterious variants within 1218 cancer susceptibility genes were analysed, and their clinical pathogenicity was assessed by ClinVar and the CharGer computational tools. FINDINGS: The cohort included in this study was recruited by the Qatar Biobank between Dec 11, 2012, and June 9, 2016. The initial dataset comprised 6218 cohort participants, and whole genome sequencing quality control filtering led to a final dataset of 6142 samples. Polygenic risk score analyses of the most common cancers in Qatar showed significant differences between the six ancestry groups (p<0·0001). Qataris with Arabian Peninsula ancestry showed the lowest polygenic risk score mean for colorectal cancer (-0·41), and those of African ancestry showed the highest average for prostate cancer (0·85). Cancer-gene rare variant analysis identified 76 Qataris (1·2% of 6142 individuals in the Qatar Genome Programme cohort) carrying ClinVar pathogenic or likely pathogenic variants in clinically actionable cancer genes. Variant analysis using CharGer identified 195 individuals carriers (3·17% of the cohort). Breast cancer pathogenic variants were over-represented in Qataris of Persian origin (22 [56·4%] of 39 BRCA1/BRCA2 variant carriers) and completely absent in those of Arabian Peninsula origin. INTERPRETATION: We observed a high degree of heterogeneity for cancer predisposition genes and polygenic risk scores across ancestries in this population from Qatar. Stratification systems could be considered for the implementation of national cancer preventive medicine programmes. FUNDING: Qatar Foundation.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias , Estudios de Cohortes , Humanos , Masculino , Neoplasias/epidemiología , Neoplasias/genética , Oncogenes , Qatar/epidemiología
3.
Biotechnol Rep (Amst) ; 31: e00666, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34557392

RESUMEN

We evaluated the seedling-stage salt tolerance of a total of 50 indigenous rice genotypes from coastal Tamil Nadu. Using a hydroponic system, we studied the different agronomic characters 14 days after exposure to six different concentrations of saline solution. Shoot and root length as well as plant biomass at seedling stage decreased with increasing salinity. Genotypes showing significant interaction and differential response towards salinity were assessed at the molecular level using 20 simple sequence repeat (SSR) markers linked with salt-tolerance QTL. These genotypes were grouped into eleven clusters based on molecular diversity analysis and eight clusters based on D2 statistical analysis. We found wide genetic distance among the genotypes studied. Simple correlation analysis revealed highly significant associations among the traits studied. The combination of morphological findings and molecular assessment revealed better salt-tolerance in a few genotypes viz. Kuzhi adichan, Poonkar, Kallundai, and Sornamugi.

4.
JCI Insight ; 6(5)2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33529170

RESUMEN

The development of prophylactic and therapeutic agents for coronavirus disease 2019 (COVID-19) is a current global health priority. Here, we investigated the presence of cross-neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in dromedary camels that were Middle East respiratory syndrome coronavirus (MERS-CoV) seropositive but MERS-CoV free. The tested 229 dromedaries had anti-MERS-CoV camel antibodies with variable cross-reactivity patterns against SARS-CoV-2 proteins, including the S trimer and M, N, and E proteins. Using SARS-CoV-2 competitive immunofluorescence immunoassays and pseudovirus neutralization assays, we found medium-to-high titers of cross-neutralizing antibodies against SARS-CoV-2 in these animals. Through linear B cell epitope mapping using phage immunoprecipitation sequencing and a SARS-CoV-2 peptide/proteome microarray, we identified a large repertoire of Betacoronavirus cross-reactive antibody specificities in these dromedaries and demonstrated that the SARS-CoV-2-specific VHH antibody repertoire is qualitatively diverse. This analysis revealed not only several SARS-CoV-2 epitopes that are highly immunogenic in humans, including a neutralizing epitope, but also epitopes exclusively targeted by camel antibodies. The identified SARS-CoV-2 cross-neutralizing camel antibodies are not proposed as a potential treatment for COVID-19. Rather, their presence in nonimmunized camels supports the development of SARS-CoV-2 hyperimmune camels, which could be a prominent source of therapeutic agents for the prevention and treatment of COVID-19.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Camelus/inmunología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/inmunología , Anticuerpos de Dominio Único/farmacología , Animales , Anticuerpos Neutralizantes/farmacología , Anticuerpos Antivirales/inmunología , Betacoronavirus/inmunología , COVID-19/inmunología , Camelus/virología , Reacciones Cruzadas , Epítopos , Femenino , Humanos , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología
5.
J Transl Med ; 18(1): 472, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33298113

RESUMEN

Aberrant metabolism is the root cause of several serious health issues, creating a huge burden to health and leading to diminished life expectancy. A dysregulated metabolism induces the secretion of several molecules which in turn trigger the inflammatory pathway. Inflammation is the natural reaction of the immune system to a variety of stimuli, such as pathogens, damaged cells, and harmful substances. Metabolically triggered inflammation, also called metaflammation or low-grade chronic inflammation, is the consequence of a synergic interaction between the host and the exposome-a combination of environmental drivers, including diet, lifestyle, pollutants and other factors throughout the life span of an individual. Various levels of chronic inflammation are associated with several lifestyle-related diseases such as diabetes, obesity, metabolic associated fatty liver disease (MAFLD), cancers, cardiovascular disorders (CVDs), autoimmune diseases, and chronic lung diseases. Chronic diseases are a growing concern worldwide, placing a heavy burden on individuals, families, governments, and health-care systems. New strategies are needed to empower communities worldwide to prevent and treat these diseases. Precision medicine provides a model for the next generation of lifestyle modification. This will capitalize on the dynamic interaction between an individual's biology, lifestyle, behavior, and environment. The aim of precision medicine is to design and improve diagnosis, therapeutics and prognostication through the use of large complex datasets that incorporate individual gene, function, and environmental variations. The implementation of high-performance computing (HPC) and artificial intelligence (AI) can predict risks with greater accuracy based on available multidimensional clinical and biological datasets. AI-powered precision medicine provides clinicians with an opportunity to specifically tailor early interventions to each individual. In this article, we discuss the strengths and limitations of existing and evolving recent, data-driven technologies, such as AI, in preventing, treating and reversing lifestyle-related diseases.


Asunto(s)
Inteligencia Artificial , Diabetes Mellitus , Enfermedad Crónica , Diabetes Mellitus/terapia , Manejo de la Enfermedad , Humanos , Medicina de Precisión
6.
Molecules ; 25(18)2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32916777

RESUMEN

Allium sativum (garlic) is widely known and is consumed as a natural prophylactic worldwide. It produces more than 200 identified chemical compounds, with more than 20 different kinds of sulfide compounds. The sulfide compounds particularly are proven to contribute to its various biological roles and pharmacological properties such as antimicrobial, antithrombotic, hypoglycemic, antitumour, and hypolipidemic. Therefore, it is often referred as disease-preventive food. Sulphur-containing compounds from A. sativum are derivatives of S-alkenyl-l-cysteine sulfoxides, ajoene molecules, thiosulfinates, sulfides, and S-allylcysteine. This review presents an overview of the water-soluble and oil-soluble sulphur based phytochemical compounds present in garlic, highlighting their mechanism of action in treating various health conditions. However, its role as a therapeutic agent should be extensively studied as it depends on factors such as the effective dosage and the suitable method of preparation.


Asunto(s)
Allium/química , Extractos Vegetales/farmacología , Compuestos de Azufre/química , Animales , Antiinfecciosos/química , Antineoplásicos/farmacología , Plaquetas/efectos de los fármacos , Cisteína/análogos & derivados , Cisteína/química , Disulfuros/química , Fibrinólisis , Ajo/química , Humanos , Factores Inmunológicos/farmacología , Neoplasias/tratamiento farmacológico , Obesidad/tratamiento farmacológico , Fitoquímicos/química , Solubilidad , Sulfóxidos/química , Azufre/química
7.
Cell Rep ; 20(10): 2408-2423, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28877474

RESUMEN

Basal p53 levels are tightly suppressed under normal conditions. Disrupting this regulation results in elevated p53 levels to induce cell cycle arrest, apoptosis, and tumor suppression. Here, we report the suppression of basal p53 levels by a nuclear, p53-regulated long noncoding RNA that we termed PURPL (p53 upregulated regulator of p53 levels). Targeted depletion of PURPL in colorectal cancer cells results in elevated basal p53 levels and induces growth defects in cell culture and in mouse xenografts. PURPL associates with MYBBP1A, a protein that binds to and stabilizes p53, and inhibits the formation of the p53-MYBBP1A complex. In the absence of PURPL, MYBBP1A interacts with and stabilizes p53. Silencing MYBBP1A significantly rescues basal p53 levels and proliferation in PURPL-deficient cells, suggesting that MYBBP1A mediates the effect of PURPL in regulating p53. These results reveal a p53-PURPL auto-regulatory feedback loop and demonstrate a role for PURPL in maintaining basal p53 levels.


Asunto(s)
Neoplasias Colorrectales/genética , ARN Largo no Codificante/genética , Proteína p53 Supresora de Tumor/genética , Apoptosis/genética , Apoptosis/fisiología , Ciclo Celular/genética , Ciclo Celular/fisiología , Puntos de Control del Ciclo Celular/genética , Puntos de Control del Ciclo Celular/fisiología , Línea Celular , Línea Celular Tumoral , Proliferación Celular/genética , Proliferación Celular/fisiología , Neoplasias Colorrectales/metabolismo , Proteínas de Unión al ADN , Proteína 1 Similar a ELAV/genética , Proteína 1 Similar a ELAV/metabolismo , Células HCT116 , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , ARN Largo no Codificante/fisiología , Proteínas de Unión al ARN , Factores de Transcripción , Proteína p53 Supresora de Tumor/metabolismo
8.
Elife ; 62017 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-28580901

RESUMEN

Thousands of long noncoding RNAs (lncRNAs) have been discovered, yet the function of the vast majority remains unclear. Here, we show that a p53-regulated lncRNA which we named PINCR (p53-induced noncoding RNA), is induced ~100-fold after DNA damage and exerts a prosurvival function in human colorectal cancer cells (CRC) in vitro and tumor growth in vivo. Targeted deletion of PINCR in CRC cells significantly impaired G1 arrest and induced hypersensitivity to chemotherapeutic drugs. PINCR regulates the induction of a subset of p53 targets involved in G1 arrest and apoptosis, including BTG2, RRM2B and GPX1. Using a novel RNA pulldown approach that utilized endogenous S1-tagged PINCR, we show that PINCR associates with the enhancer region of these genes by binding to RNA-binding protein Matrin 3 that, in turn, associates with p53. Our findings uncover a critical prosurvival function of a p53/PINCR/Matrin 3 axis in response to DNA damage in CRC cells.


Asunto(s)
Neoplasias Colorrectales/patología , Daño del ADN , Regulación de la Expresión Génica , Proteínas Asociadas a Matriz Nuclear/metabolismo , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular , Humanos
9.
Arch Biochem Biophys ; 589: 108-19, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26416722

RESUMEN

The emergence of a worldwide obesity epidemic has dramatically increased the prevalence of insulin resistance and metabolic syndrome, predisposing individuals to a greater risk for the development of non-alcoholic fatty liver disease, type II diabetes and atherosclerotic cardiovascular diseases. Current available pharmacological interventions combined with diet and exercise-based managements are still poorly effective for weight management, likely in part due to an incomplete understanding of regulatory mechanisms and pathways contributing to the systemic metabolic abnormalities under disturbed energy homeostasis. MicroRNAs, small non-coding RNAs that regulate posttranscriptional gene expression, have been increasingly described to influence shifts in metabolic pathways under various obesity-related disease settings. Here we review recent discoveries of the mechanistic role that microRNAs play in regulating metabolic functions in liver and adipose tissues involved in obesity associated disorders, and briefly discusses the potential candidates that are being pursued as viable therapeutic targets.


Asunto(s)
MicroARNs , Obesidad/complicaciones , Obesidad/genética , Adipogénesis , Animales , Dislipidemias/complicaciones , Humanos , Resistencia a la Insulina , MicroARNs/genética , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Obesidad/metabolismo , Obesidad/patología
10.
Proc Natl Acad Sci U S A ; 112(13): E1550-8, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25775580

RESUMEN

The transcription factor caudal-type homeobox 1 (CDX1) is a key regulator of differentiation in the normal colon and in colorectal cancer (CRC). CDX1 activates the expression of enterocyte genes, but it is not clear how the concomitant silencing of stem cell genes is achieved. MicroRNAs (miRNAs) are important mediators of gene repression and have been implicated in tumor suppression and carcinogenesis, but the roles of miRNAs in differentiation, particularly in CRC, remain poorly understood. Here, we identified microRNA-215 (miR-215) as a direct transcriptional target of CDX1 by using high-throughput small RNA sequencing to profile miRNA expression in two pairs of CRC cell lines: CDX1-low HCT116 and HCT116 with stable CDX1 overexpression, and CDX1-high LS174T and LS174T with stable CDX1 knockdown. Validation of candidate miRNAs identified by RNA-seq in a larger cell-line panel revealed miR-215 to be most significantly correlated with CDX1 expression. Quantitative ChIP-PCR and promoter luciferase assays confirmed that CDX1 directly activates miR-215 transcription. miR-215 expression is depleted in FACS-enriched cancer stem cells compared with unsorted samples. Overexpression of miR-215 in poorly differentiated cell lines causes a decrease in clonogenicity, whereas miR-215 knockdown increases clonogenicity and impairs differentiation in CDX1-high cell lines. We identified the genome-wide targets of miR-215 and found that miR-215 mediates the repression of cell cycle and stemness genes downstream of CDX1. In particular, the miR-215 target gene BMI1 has been shown to promote stemness and self-renewal and to vary inversely with CDX1. Our work situates miR-215 as a link between CDX1 expression and BMI1 repression that governs differentiation in CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas de Homeodominio/metabolismo , MicroARNs/metabolismo , Células Madre Neoplásicas/citología , Diferenciación Celular , Línea Celular Tumoral , Colon/metabolismo , Islas de CpG , Perfilación de la Expresión Génica , Células HCT116 , Humanos , Complejo Represivo Polycomb 1/metabolismo , Análisis de Secuencia de ARN , Transfección
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