Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Heliyon ; 10(8): e29572, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38699748

RESUMO

Sepsis is a life-threatening illness caused by the dysregulated host response to infection. Nevertheless, our current knowledge of the microbial landscape in the blood of septic patients is still limited. Next-generation sequencing (NGS) is a sensitive method to quantitatively characterize microbiomes at various sites of the human body. In this study, we analyzed the blood microbial DNA of 22 adult patients with sepsis and 3 healthy subjects. The presence of non-human DNA was identified in both healthy and septic subjects. Septic patients had a markedly altered microbial DNA profile compared to healthy subjects over α- and ß-diversity. Unexpectedly, the patients could be further divided into two subgroups (C1 and C2) based on ß-diversity analysis. C1 patients showed much higher bacteria, viruses, fungi, and archaea abundance, and a higher level of α-diversity (Chao1, Observed and Shannon index) than both C2 patients and healthy subjects. The most striking difference was seen in the case of Streptomyces violaceusniger, Phenylobacterium sp. HYN0004, Caulobacter flavus, Streptomyces sp. 11-1-2, and Phenylobacterium zucineum, the abundance of which was the highest in the C1 group. Notably, C1 patients had a significantly poorer outcome than C2 patients. Moreover, by analyzing the patterns of microbe-microbe interactions in healthy and septic subjects, we revealed that C1 and C2 patients exhibited distinct co-occurrence and co-exclusion relationships. Together, our study uncovered two distinct microbial signatures in the blood of septic patients. Compositional and ecological analysis of blood microbial DNA may thus be useful in predicting mortality of septic patients.

2.
Cancer Cell ; 41(8): 1450-1465.e8, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37478851

RESUMO

Carnobacterium maltaromaticum was found to be specifically depleted in female patients with colorectal cancer (CRC). Administration of C. maltaromaticum reduces intestinal tumor formation in two murine CRC models in a female-specific manner. Estrogen increases the attachment and colonization of C. maltaromaticum via increasing the colonic expression of SLC3A2 that binds to DD-CPase of this bacterium. Metabolomic and transcriptomic profiling unveils the increased gut abundance of vitamin D-related metabolites and the mucosal activation of vitamin D receptor (VDR) signaling in C. maltaromaticum-gavaged mice in a gut microbiome- and VDR-dependent manner. In vitro fermentation system confirms the metabolic cross-feeding of C. maltaromaticum with Faecalibacterium prausnitzii to convert C. maltaromaticum-produced 7-dehydrocholesterol into vitamin D for activating the host VDR signaling. Overall, C. maltaromaticum colonizes the gut in an estrogen-dependent manner and acts along with other microbes to augment the intestinal vitamin D production to activate the host VDR for suppressing CRC.


Assuntos
Neoplasias Colorretais , Vitamina D , Camundongos , Feminino , Animais , Vitamina D/metabolismo , Carnobacterium/metabolismo , Estrogênios/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo
3.
FEMS Microbiol Rev ; 47(4)2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407433

RESUMO

The gut microbiota plays a crucial role in regulating various host metabolic, immune, and neuroendocrine functions, and has a significant impact on human health. Several lines of evidence suggest that gut dysbiosis is associated with a variety of diseases, including cancer. The gut microbiota can impact the development and progression of cancer through a range of mechanisms, such as regulating cell proliferation and death, modulating the host immune response, and altering the host metabolic state. Gene regulatory programs are considered critical mediators between the gut microbiota and host phenotype, of which RNA N6-methyladenosine (m6A) modifications have attracted much attention recently. Aberrant m6A modifications have been shown to play a crucial role in cancer development. This review aims to provide an overview of the diverse roles of gut microbiota and RNA m6A modifications in cancer and highlight their potential interactions in cancer development.


Assuntos
Microbioma Gastrointestinal , Neoplasias , Humanos , Microbioma Gastrointestinal/genética , Proliferação de Células , Neoplasias/genética , RNA
4.
Wiley Interdiscip Rev RNA ; 14(3): e1764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36149809

RESUMO

Sepsis is defined as life-threatening organ dysfunction caused by the host immune dysregulation to infection. It is a highly heterogeneous syndrome with complex pathophysiological mechanisms. The host immune response to sepsis can be divided into hyper-inflammatory and immune-suppressive phases which could exist simultaneously. In the initial stage, systemic immune response is activated after exposure to pathogens. Both innate and adaptive immune cells undergo epigenomic, transcriptomic, and functional reprogramming, resulting in systemic and persistent inflammatory responses. Following the hyper-inflammatory phase, the body is in a state of continuous immunosuppression, which is related to immune cell apoptosis, metabolic failure, and epigenetic reprogramming. Immunosuppression leads to increased susceptibility to secondary infections in patients with sepsis. RNA N6-Methyladenosine (m6A) has been recognized as an indispensable epitranscriptomic modification involved in both physiological and pathological processes. Recent studies suggest that m6A could reprogram both innate and adaptive immune cells through posttranscriptional regulation of RNA metabolism. Dysregulated m6A modifications contribute to the pathogenesis of immune-related diseases. In this review, we summarize immune cell changes and the potential role of m6A modification in sepsis. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Processing > RNA Editing and Modification.


Assuntos
RNA , Sepse , Humanos , RNA/metabolismo , Metilação , Regulação da Expressão Gênica , Sepse/genética
5.
Int J Mol Sci ; 23(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36142852

RESUMO

The colonization of Helicobacter pylori (H. pylori) in human gastric mucosa is highly associated with the occurrence of gastritis, peptic ulcer, and gastric cancer. Antibiotics, including amoxicillin, clarithromycin, furazolidone, levofloxacin, metronidazole, and tetracycline, are commonly used and considered the major treatment regimens for H. pylori eradication, which is, however, becoming less effective by the increasing prevalence of H pylori resistance. Thus, it is urgent to understand the molecular mechanisms of H. pylori pathogenesis and develop alternative therapeutic strategies. In this review, we focus on the virulence factors for H. pylori colonization and survival within host gastric mucosa and the host antimicrobial responses against H. pylori infection. Moreover, we describe the current treatments for H. pylori eradication and provide some insights into new therapeutic strategies for H. pylori infection.


Assuntos
Anti-Infecciosos , Infecções por Helicobacter , Helicobacter pylori , Amoxicilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Claritromicina , Farmacorresistência Bacteriana , Furazolidona/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Humanos , Levofloxacino , Metronidazol/uso terapêutico , Tetraciclina , Fatores de Virulência
6.
Biomedicines ; 10(8)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-36009465

RESUMO

Gastrointestinal (GI) cancer, referring to cancers of the digestive system such as colorectal cancer (CRC), gastric cancer (GC), and liver cancer, is a major cause of cancer-related deaths in the world. A series of genetic, epigenetic, and epitranscriptomic changes occur during the development of GI cancer. The identification of these molecular events provides potential diagnostic, prognostic, and therapeutic targets for cancer patients. RNA modification is required in the posttranscriptional regulation of RNA metabolism, including splicing, intracellular transport, degradation, and translation. RNA modifications such as N6-methyladenosine (m6A) and N1-methyladenosine (m1A) are dynamically regulated by three different types of regulators named methyltransferases (writers), RNA binding proteins (readers), and demethylases (erasers). Recent studies have pointed out that abnormal RNA modification contributes to GI tumorigenesis and progression. In this review, we summarize the latest findings on the functional significance of RNA modification in GI cancer and discuss the therapeutic potential of epitranscriptomic inhibitors for cancer treatment.

7.
Oncogene ; 41(23): 3278-3288, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523946

RESUMO

Cancer-related genes have evolved specific genetic and genomic features to favor tumor suppression. Previously we reported that tumor suppressor genes (TSGs) acquired high promoter CpG dinucleotide frequencies during evolution to maintain high expression in normal tissues and resist cancer-specific downregulation. In this study, we investigated whether 3'untranslated regions (3'UTRs) of TSGs have evolved specific features to carry out similar functions. We found that 3'UTRs of TSGs, especially those involved in multiple histological types and pediatric cancers, are longer than those of non-cancer genes. 3'UTRs of TSGs also exhibit higher density of binding sites for RNA-binding proteins (RBPs), particularly those having high affinities to C-rich motifs. Both longer 3'UTR length and RBP binding sites enrichment are correlated with higher gene expression in normal tissues across tissue types. Moreover, both features together with the correlated N6-methyladenosine modification and the extent of protein-protein interactions are positively associated with the ability of TSGs to resist cancer-specific downregulation. These results were successfully validated with independent datasets. Collectively, these findings indicate that TSGs have evolved longer 3'UTR with increased propensity to RBP binding, N6-methyladenosine modification and protein-protein interactions for optimizing their tumor-suppressing functions.


Assuntos
Genes Supressores de Tumor , Neoplasias , Regiões 3' não Traduzidas/genética , Sítios de Ligação/genética , Criança , Humanos , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas
8.
Cancer Res ; 82(8): 1482-1491, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35247889

RESUMO

Cancer-related genes are under intense evolutionary pressure. In this study, we conjecture that X-linked tumor suppressor genes (TSG) are not protected by the Knudson's two-hit mechanism and are therefore subject to negative selection. Accordingly, nearly all mammalian species exhibited lower TSG-to-noncancer gene ratios on their X chromosomes compared with nonmammalian species. Synteny analysis revealed that mammalian X-linked TSGs were depleted shortly after the emergence of the XY sex-determination system. A phylogeny-based model unveiled a higher X chromosome-to-autosome relocation flux for human TSGs. This was verified in other mammals by assessing the concordance/discordance of chromosomal locations of mammalian TSGs and their orthologs in Xenopus tropicalis. In humans, X-linked TSGs are younger or larger in size. Consistently, pan-cancer analysis revealed more frequent nonsynonymous somatic mutations of X-linked TSGs. These findings suggest that relocation of TSGs out of the X chromosome could confer a survival advantage by facilitating evasion of single-hit inactivation. SIGNIFICANCE: This work unveils extensive trafficking of TSGs from the X chromosome to autosomes during evolution, thus identifying X-linked TSGs as a genetic Achilles' heel in tumor suppression.


Assuntos
Evolução Molecular , Genes Supressores de Tumor , Neoplasias , Cromossomo X , Animais , Humanos , Mamíferos/genética , Neoplasias/genética , Oncogenes , Sintenia , Cromossomo X/genética , Xenopus
9.
Front Immunol ; 13: 790924, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222376

RESUMO

Ankylosing spondylitis (AS) is a chronic systemic autoimmune disease characterized by inflammation, bone erosion, spur formation of the spine and the sacroiliac joints. However, the etiology and molecular pathogenesis of AS remain largely unclear. Recently, a growing number of studies showed that long non-coding RNAs (lncRNAs) played critical roles in the development and progression of autoimmune and orthopedic conditions, including AS. Studies demonstrated that a myriad of lncRNAs (e.g. H19, MEG3, LOC645166) pertinent to regulation of inflammatory signals were deregulated in AS. A number of lncRNAs might also serve as new biomarkers for the diagnosis and predicting the outcomes of AS. In this review, we summarize lncRNA profiling studies on AS and the functional roles and mechanism of key lncRNAs relevant to AS pathogenesis. We also discuss their potential values as biomarkers and druggable targets for this potentially disabling condition.


Assuntos
RNA Longo não Codificante , Espondilite Anquilosante , Biomarcadores , Humanos , Inflamação/genética , Inflamação/patologia , RNA Longo não Codificante/genética , Articulação Sacroilíaca/patologia , Espondilite Anquilosante/diagnóstico
10.
Autophagy ; 18(9): 2246-2248, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35067165

RESUMO

As the coronavirus disease 2019 (COVID-19) pandemic continues to wreak havoc, researchers around the globe are working together to understand how the responsible agent - severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) damages the respiratory system and other organs. Macroautophagy/autophagy is an innate immune response against viral infection and is known to be manipulated by positive-strand RNA viruses, including SARS-CoV-2. Nevertheless, the link between autophagic subversion and cell death or inflammation in COVID-19 remains unclear. Emerging evidence suggests that SARS-CoV-2 could trigger pyroptosis, a form of inflammatory programmed cell death characterized by the activation of inflammasomes and CASP1 (caspase 1) and the formation of transmembrane pores by GSDMD (gasdermin D). In this connection, autophagic flux impairment is a known activator of inflammasomes. This prompted us to investigate if SARS-CoV-2 could target autophagy to induce inflammasome-dependent pyroptosis in lung epithelial cells.Abbreviations: ATP6AP1: ATPase H+ transporting accessory protein 1; CASP1: caspase 1; COVID-19: coronavirus disease 2019; GSDMD: gasdermin D; IL1B: interleukin 1 beta; IL18: interleukin 18; KRT 18: keratin 18; NLRP3: NLR family pyrin domain containing 3; NOD: nucleotide oligomerization domain; NSP6: non-structural protein 6; TFEB: transcription factor EB; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2.


Assuntos
COVID-19 , ATPases Vacuolares Próton-Translocadoras , Autofagia , Caspase 1/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Pulmão/metabolismo , Lisossomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , SARS-CoV-2 , ATPases Vacuolares Próton-Translocadoras/metabolismo
11.
Autophagy ; 18(9): 2050-2067, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34989311

RESUMO

Clostridioides difficile infection (CDI) is a common cause of nosocomial diarrhea. TcdB is a major C. difficile exotoxin that activates macrophages to promote inflammation and epithelial damage. Lysosome impairment is a known trigger for inflammation. Herein, we hypothesize that TcdB could impair macrophage lysosomal function to mediate inflammation during CDI. Effects of TcdB on lysosomal function and the downstream pro-inflammatory SQSTM1/p62-NFKB (nuclear factor kappa B) signaling were assessed in cultured macrophages and in a murine CDI model. Protective effects of two lysosome activators (i.e., vitamin D3 and carbamazepine) were assessed. Results showed that TcdB inhibited CTNNB1/ß-catenin activity to downregulate MITF (melanocyte inducing transcription factor) and its direct target genes encoding components of lysosomal membrane vacuolar-type ATPase, thereby suppressing lysosome acidification in macrophages. The resulting lysosomal dysfunction then impaired autophagic flux and activated SQSTM1-NFKB signaling to drive the expression of IL1B/IL-1ß (interleukin 1 beta), IL8 and CXCL2 (chemokine (C-X-C motif) ligand 2). Restoring MITF function by enforced MITF expression or restoring lysosome acidification with 1α,25-dihydroxyvitamin D3 or carbamazepine suppressed pro-inflammatory cytokine expression in vitro. In mice, gavage with TcdB-hyperproducing C. difficile or injection of TcdB into ligated colon segments caused prominent MITF downregulation in macrophages. Vitamin D3 and carbamazepine lessened TcdB-induced lysosomal dysfunction, inflammation and histological damage. In conclusion, TcdB inhibits the CTNNB1-MITF axis to suppress lysosome acidification and activates the downstream SQSTM1-NFKB signaling in macrophages during CDI. Vitamin D3 and carbamazepine protect against CDI by restoring MITF expression and lysosomal function in mice.Abbreviations: ATP6V0B: ATPase H+ transporting V0 subunit b; ATP6V0C: ATPase H+ transporting V0 subunit c; ATP6V0E1: ATPase H+ transporting V0 subunit e1; ATP6V1H: ATPase H+ transporting V1 subunit H; CBZ: carbamazepine; CDI: C. difficile infection; CXCL: chemokine C-X-X motif ligand; IL: interleukin; LAMP1: lysosomal-associated membrane protein 1; LC3: microtubule-associated protein 1 light chain 3; LEF: lymphoid enhancer binding factor 1; MITF: melanocyte inducing transcription factor; NFKB: nuclear factor kappa B; PMA: phorbol 12-myristate 13-acetate; TcdA: Clostridial toxin A; TcdB: Clostridial toxin B; TFE3: transcription factor E3; TFEB: transcription factor EB.


Assuntos
Toxinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , ATPases Vacuolares Próton-Translocadoras , Animais , Autofagia , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/farmacologia , Carbamazepina/metabolismo , Carbamazepina/farmacologia , Colecalciferol/farmacologia , Infecções por Clostridium/metabolismo , Concentração de Íons de Hidrogênio , Inflamação/metabolismo , Lisossomos/metabolismo , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Proteína Sequestossoma-1/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo
12.
Cell Death Differ ; 29(6): 1240-1254, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34997207

RESUMO

A recent mutation analysis suggested that Non-Structural Protein 6 (NSP6) of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a key determinant of the viral pathogenicity. Here, by transcriptome analysis, we demonstrated that the inflammasome-related NOD-like receptor signaling was activated in SARS-CoV-2-infected lung epithelial cells and Coronavirus Disease 2019 (COVID-19) patients' lung tissues. The induction of inflammasomes/pyroptosis in patients with severe COVID-19 was confirmed by serological markers. Overexpression of NSP6 triggered NLRP3/ASC-dependent caspase-1 activation, interleukin-1ß/18 maturation, and pyroptosis of lung epithelial cells. Upstream, NSP6 impaired lysosome acidification to inhibit autophagic flux, whose restoration by 1α,25-dihydroxyvitamin D3, metformin or polydatin abrogated NSP6-induced pyroptosis. NSP6 directly interacted with ATP6AP1, a vacuolar ATPase proton pump component, and inhibited its cleavage-mediated activation. L37F NSP6 variant, which was associated with asymptomatic COVID-19, exhibited reduced binding to ATP6AP1 and weakened ability to impair lysosome acidification to induce pyroptosis. Consistently, infection of cultured lung epithelial cells with live SARS-CoV-2 resulted in autophagic flux stagnation, inflammasome activation, and pyroptosis. Overall, this work supports that NSP6 of SARS-CoV-2 could induce inflammatory cell death in lung epithelial cells, through which pharmacological rectification of autophagic flux might be therapeutically exploited.


Assuntos
COVID-19 , Proteínas do Nucleocapsídeo de Coronavírus , Proteína 3 que Contém Domínio de Pirina da Família NLR , SARS-CoV-2 , ATPases Vacuolares Próton-Translocadoras , COVID-19/metabolismo , COVID-19/virologia , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , ATPases Vacuolares Próton-Translocadoras/metabolismo
13.
Pain Ther ; 10(2): 1511-1522, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34510386

RESUMO

BACKGROUND: The treatment for herpetic-related neuralgia focuses on symptom control by use of antiviral drugs, anticonvulsants, and tricyclic antidepressants. We aimed to explore the clinical characteristics associated with medication responsiveness, and to build a classifier for identification of patients who have risk of inadequate pain management. METHODS: We recruited herpetic-related neuralgia patients during a 3-year period. Patients were stratified into a medication-resistant pain (MRP) group when the pain decrease in the visual analogue scale (VAS) is < 3 points, and otherwise a medication-sensitive pain (MSP) group. Multivariate logistic regression was performed to determine the factors associated with MRP. We fitted four machine learning (ML) models, namely logistic regression, random forest, supporting vector machines (SVM), and naïve Bayes with clinical characteristics gathered at admission to identify patients with MRP. RESULTS: A total of 213 patients were recruited, and 132 (61.97%) patients were diagnosed with MRP. Subacute herpes zoster (HZ) (vs. acute, OR 8.95, 95% CI 3.15-29.48, p = 0.0001), severe lesion (vs. mild lesion, OR 3.84, 95% CI 1.44-10.81, p = 0.0084), depressed mood (unit increase OR 1.10, 95% CI 1.00-1.20, p = 0.0447), and hypertension (hypertension, vs. no hypertension, OR 0.36, 95% CI 0.14-0.87, p = 0.0266) were significantly associated with MRP. Among four ML models, SVM had the highest accuracy (0.917) and receiver operating characteristic-area under the curve (0.918) to discriminate MRP from MSP. Phase of disease is the most important feature when fitting ML models. CONCLUSIONS: Clinical characteristics collected before treatment could be adopted to identify patients with MRP.

14.
Brief Bioinform ; 22(2): 1466-1475, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33620066

RESUMO

Coronavirus disease 2019 (COVID-19) has spread rapidly worldwide, causing significant mortality. There is a mechanistic relationship between intracellular coronavirus replication and deregulated autophagosome-lysosome system. We performed transcriptome analysis of peripheral blood mononuclear cells (PBMCs) from COVID-19 patients and identified the aberrant upregulation of genes in the lysosome pathway. We further determined the capability of two circulating markers, namely microtubule-associated proteins 1A/1B light chain 3B (LC3B) and (p62/SQSTM1) p62, both of which depend on lysosome for degradation, in predicting the emergence of moderate-to-severe disease in COVID-19 patients requiring hospitalization for supplemental oxygen therapy. Logistic regression analyses showed that LC3B was associated with moderate-to-severe COVID-19, independent of age, sex and clinical risk score. A decrease in LC3B concentration <5.5 ng/ml increased the risk of oxygen and ventilatory requirement (adjusted odds ratio: 4.6; 95% CI: 1.1-22.0; P = 0.04). Serum concentrations of p62 in the moderate-to-severe group were significantly lower in patients aged 50 or below. In conclusion, lysosome function is deregulated in PBMCs isolated from COVID-19 patients, and the related biomarker LC3B may serve as a novel tool for stratifying patients with moderate-to-severe COVID-19 from those with asymptomatic or mild disease. COVID-19 patients with a decrease in LC3B concentration <5.5 ng/ml will require early hospital admission for supplemental oxygen therapy and other respiratory support.


Assuntos
COVID-19/virologia , Leucócitos Mononucleares/metabolismo , Lisossomos/metabolismo , Proteínas Associadas aos Microtúbulos/sangue , SARS-CoV-2/metabolismo , Adulto , Autofagia , Biomarcadores/sangue , COVID-19/sangue , Ciclo Celular , Colesterol/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Ligação a RNA/sangue , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Gastroenterology ; 160(4): 1179-1193.e14, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32920015

RESUMO

BACKGROUND & AIMS: Streptococcus thermophilus was identified to be depleted in patients with colorectal cancer (CRC) by shotgun metagenomic sequencing of 526 multicohort fecal samples. Here, we aim to investigate whether this bacterium could act as a prophylactic for CRC prevention. METHODS: The antitumor effects of S thermophilus were assessed in cultured colonic epithelial cells and in 2 murine models of intestinal tumorigenesis. The tumor-suppressive protein produced by S thermophilus was identified by mass spectrometry and followed by ß-galactosidase activity assay. The mutant strain of S thermophilus was constructed by homologous recombination. The effect of S thermophilus on the gut microbiota composition was assessed by shotgun metagenomic sequencing. RESULTS: Oral gavage of S thermophilus significantly reduced tumor formation in both Apcmin/+ and azoxymethane-injected mice. Coincubation with S thermophilus or its conditioned medium decreased the proliferation of cultured CRC cells. ß-Galactosidase was identified as the critical protein produced by S thermophilus by mass spectrometry screening and ß-galactosidase activity assay. ß-Galactosidase secreted by S thermophilus inhibited cell proliferation, lowered colony formation, induced cell cycle arrest, and promoted apoptosis of cultured CRC cells and retarded the growth of CRC xenograft. The mutant S thermophilus without functional ß-galactosidase lost its tumor-suppressive effect. Also, S thermophilus increased the gut abundance of known probiotics, including Bifidobacterium and Lactobacillus via ß-galactosidase. ß-Galactosidase-dependent production of galactose interfered with energy homeostasis to activate oxidative phosphorylation and downregulate the Hippo pathway kinases, which partially mediated the anticancer effects of S thermophilus. CONCLUSION: S thermophilus is a novel prophylactic for CRC prevention in mice. The tumor-suppressive effect of S thermophilus is mediated at least by the secretion of ß-galactosidase.


Assuntos
Proteínas de Bactérias/metabolismo , Neoplasias Colorretais/prevenção & controle , Probióticos/administração & dosagem , Streptococcus thermophilus/enzimologia , beta-Galactosidase/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Azoximetano/administração & dosagem , Azoximetano/toxicidade , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/induzido quimicamente , Colo/microbiologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Humanos , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Experimentais/microbiologia , Neoplasias Experimentais/prevenção & controle , Probióticos/metabolismo , Streptococcus thermophilus/genética , beta-Galactosidase/genética
16.
Microbiome ; 8(1): 108, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678024

RESUMO

BACKGROUND: Altered microbiome composition and aberrant promoter hypermethylation of tumor suppressor genes (TSGs) are two important hallmarks of colorectal cancer (CRC). Here we performed concurrent 16S rRNA gene sequencing and methyl-CpG binding domain-based capture sequencing in 33 tissue biopsies (5 normal colonic mucosa tissues, 4 pairs of adenoma and adenoma-adjacent tissues, and 10 pairs of CRC and CRC-adjacent tissues) to identify significant associations between TSG promoter hypermethylation and CRC-associated bacteria, followed by functional validation of the methylation-associated bacteria. RESULTS: Fusobacterium nucleatum and Hungatella hathewayi were identified as the top two methylation-regulating bacteria. Targeted analysis on bona fide TSGs revealed that H. hathewayi and Streptococcus spp. significantly correlated with CDX2 and MLH1 promoter hypermethylation, respectively. Mechanistic validation with cell-line and animal models revealed that F. nucleatum and H. hathewayi upregulated DNA methyltransferase. H. hathewayi inoculation also promoted colonic epithelial cell proliferation in germ-free and conventional mice. CONCLUSION: Our integrative analysis revealed previously unknown epigenetic regulation of TSGs in host cells through inducing DNA methyltransferase by F. nucleatum and H. hathewayi, and established the latter as CRC-promoting bacteria. Video abstract.


Assuntos
Clostridiaceae/patogenicidade , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Metilação de DNA , Células Epiteliais/metabolismo , Fusobacterium nucleatum/patogenicidade , Genes Supressores de Tumor , Regiões Promotoras Genéticas/genética , Idoso , Animais , Epigênese Genética , Epigenoma , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética
17.
J Cell Mol Med ; 24(11): 5966-5972, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32351034

RESUMO

Atopic dermatitis (AD) is a chronic and recurrent inflammatory skin disease, affecting up to 10% to 20% of children and 3% of adults. Although allergen sensitization, skin barrier abnormalities and type 2 immune responses are involved, the exact molecular pathogenesis of AD remains unclear. MicroRNAs (miRNAs) are short (19-25 nucleotides) single-stranded RNA molecules that regulate gene expression at post-transcriptional level and are implicated in the pathogenesis of many inflammatory and immunological skin disorders. This systematic review sought to summarize our current understanding regarding the role of miRNAs in AD development. We searched articles indexed in PubMed (MEDLINE) and Web of Science databases using Medical Subject Heading (MeSH) or Title/Abstract words ('microRNA/miRNA' and 'atopic dermatitis/eczema') from inception through January 2020. Observational studies revealed dysregulation of miRNAs, including miR-143, miR-146a, miR-151a, miR-155 and miR-223, in AD patients. Experimental studies confirmed their functions in regulating keratinocyte proliferation/apoptosis, cytokine signalling and nuclear factor-κB-dependent inflammatory responses, together with T helper 17 and regulatory T cell activities. Altogether, this systematic review brings together contemporary findings on how deregulation of miRNAs contributes to AD.


Assuntos
Dermatite Atópica/genética , MicroRNAs/genética , Regulação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Modelos Biológicos
18.
Gastroenterology ; 155(2): 529-541.e5, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29689266

RESUMO

BACKGROUND & AIMS: Patients with colorectal cancer (CRC) have a different gut microbiome signature than individuals without CRC. Little is known about the viral component of CRC-associated microbiome. We aimed to identify and validate viral taxonomic markers of CRC that might be used in detection of the disease or predicting outcome. METHODS: We performed shotgun metagenomic analyses of viromes of fecal samples from 74 patients with CRC (cases) and 92 individuals without CRC (controls) in Hong Kong (discovery cohort). Viral sequences were classified by taxonomic alignment against an integrated microbial reference genome database. Viral markers associated with CRC were validated using fecal samples from 3 separate cohorts: 111 patients with CRC and 112 controls in Hong Kong, 46 patients with CRC and 63 controls in Austria, and 91 patients with CRC and 66 controls in France and Germany. Using abundance profiles of CRC-associated virome genera, we constructed random survival forest models to identify those associated with patient survival times. RESULTS: The diversity of the gut bacteriophage community was significantly increased in patients with CRC compared with controls. Twenty-two viral taxa discriminated cases from controls with an area under the receiver operating characteristic curve of 0.802 in the discovery cohort. The viral markers were validated in 3 cohorts, with area under the receiver operating characteristic curves of 0.763, 0.736, and 0.715, respectively. Clinical subgroup analysis showed that dysbiosis of the gut virome was associated with early- and late-stage CRC. A combination of 4 taxonomic markers associated with reduced survival of patients with CRC (log-rank test, P = 8.1 × 10-6) independently of tumor stage, lymph node metastases, or clinical parameters. We found altered interactions between bacteriophages and oral bacterial commensals in fecal samples from patients with CRC compared with controls. CONCLUSIONS: In a metagenomic analysis of fecal samples from patients and controls, we identified virome signatures associated with CRC. These data might be used to develop tools to identify individuals with CRC or predict outcomes.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/virologia , Disbiose/virologia , Microbioma Gastrointestinal/genética , Vírus/genética , Áustria/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Estudos Transversais , Disbiose/diagnóstico por imagem , Fezes/virologia , Feminino , França/epidemiologia , Alemanha/epidemiologia , Hong Kong/epidemiologia , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Análise de Sobrevida
19.
Medicine (Baltimore) ; 94(46): e1875, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26579799

RESUMO

Drug fever is frequently underrecognized by clinicians despite its common occurrence. Fever induced by piperacillin/tazobactam has not been reported in scoliosis correction surgery.Drug fever caused by piperacillin/tazobactam in a scoliosis patient was described.A 36-year-old woman with adult scoliosis undergoing correction surgery was reported. She developed a fever after an intake of piperacillin/tazobactam for 3 days. Eosinophil count, erythrocyte sedimentation rate, and C-reactive proteins were increased in her blood examination. Thorough history, chest radiography, blood cultures, physical examination, and urinalysis revealed no evidences of fever. A drug fever is therefore considered. The fever lasted for 2 weeks and her body temperature come back to normal 4 days after piperacillin/tazobactam cessation.Fever could be caused by piperacillin/tazobactam. The drug fever's diagnosis is easily confounded by a co-occurring infection. Therefore, it is crucial for clinicians to doubt drugs as a reason when no other origin of fever could be identified in a patient.


Assuntos
Antibacterianos/efeitos adversos , Febre/induzido quimicamente , Ácido Penicilânico/análogos & derivados , Complicações Pós-Operatórias/induzido quimicamente , Escoliose/cirurgia , Adulto , Combinação de Medicamentos , Feminino , Febre/diagnóstico , Humanos , Ácido Penicilânico/efeitos adversos , Piperacilina/efeitos adversos , Combinação Piperacilina e Tazobactam , Complicações Pós-Operatórias/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA