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1.
Proc Natl Acad Sci U S A ; 117(46): 28806-28815, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139577

RESUMO

Akt activation up-regulates the intracellular levels of reactive oxygen species (ROS) by inhibiting ROS scavenging. Of the Akt isoforms, Akt3 has also been shown to up-regulate ROS by promoting mitochondrial biogenesis. Here, we employ a set of isogenic cell lines that express different Akt isoforms, to show that the most robust inducer of ROS is Akt3. As a result, Akt3-expressing cells activate the DNA damage response pathway, express high levels of p53 and its direct transcriptional target miR-34, and exhibit a proliferation defect, which is rescued by the antioxidant N-acetylcysteine. The importance of the DNA damage response in the inhibition of cell proliferation by Akt3 was confirmed by Akt3 overexpression in p53-/- and INK4a-/-/Arf-/- mouse embryonic fibroblasts (MEFs), which failed to inhibit cell proliferation, despite the induction of high levels of ROS. The induction of ROS by Akt3 is due to the phosphorylation of the NADPH oxidase subunit p47phox, which results in NADPH oxidase activation. Expression of Akt3 in p47phox-/- MEFs failed to induce ROS and to inhibit cell proliferation. Notably, the proliferation defect was rescued by wild-type p47phox, but not by the phosphorylation site mutant of p47phox In agreement with these observations, Akt3 up-regulates p53 in human cancer cell lines, and the expression of Akt3 positively correlates with the levels of p53 in a variety of human tumors. More important, Akt3 alterations correlate with a higher frequency of mutation of p53, suggesting that tumor cells may adapt to high levels of Akt3, by inactivating the DNA damage response.


Assuntos
Dano ao DNA , NADPH Oxidases/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Linhagem Celular , Ativação Enzimática , Camundongos , NADPH Oxidases/genética , Oxirredução , Estresse Oxidativo/genética , Fosfoproteínas/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
2.
Gastroenterology ; 161(1): 255-270.e4, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33844988

RESUMO

BACKGROUND AND AIMS: The molecular mechanisms underlying successful fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (rCDI) remain poorly understood. The primary objective of this study was to characterize alterations in microRNAs (miRs) following FMT for rCDI. METHODS: Sera from 2 prospective multicenter randomized controlled trials were analyzed for miRNA levels with the use of the Nanostring nCounter platform and quantitative reverse-transcription (RT) polymerase chain reaction (PCR). In addition, rCDI-FMT and toxin-treated animals and ex vivo human colonoids were used to compare intestinal tissue and circulating miRs. miR inflammatory gene targets in colonic epithelial and peripheral blood mononuclear cells were evaluated by quantitative PCR (qPCR) and 3'UTR reporter assays. Colonic epithelial cells were used for mechanistic, cytoskeleton, cell growth, and apoptosis studies. RESULTS: miRNA profiling revealed up-regulation of 64 circulating miRs 4 and 12 weeks after FMT compared with screening, of which the top 6 were validated in the discovery cohort by means of RT-qPCR. In a murine model of relapsing-CDI, RT-qPCR analyses of sera and cecal RNA extracts demonstrated suppression of these miRs, an effect reversed by FMT. In mouse colon and human colonoids, C difficile toxin B (TcdB) mediated the suppressive effects of CDI on miRs. CDI dysregulated DROSHA, an effect reversed by FMT. Correlation analyses, qPCR ,and 3'UTR reporter assays revealed that miR-23a, miR-150, miR-26b, and miR-28 target directly the 3'UTRs of IL12B, IL18, FGF21, and TNFRSF9, respectively. miR-23a and miR-150 demonstrated cytoprotective effects against TcdB. CONCLUSIONS: These results provide novel and provocative evidence that modulation of the gut microbiome via FMT induces alterations in circulating and intestinal tissue miRs. These findings contribute to a greater understanding of the molecular mechanisms underlying FMT and identify new potential targets for therapeutic intervention in rCDI.


Assuntos
MicroRNA Circulante/sangue , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Intestinos/microbiologia , Reinfecção , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , MicroRNA Circulante/genética , Infecções por Clostridium/sangue , Infecções por Clostridium/genética , Infecções por Clostridium/microbiologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Técnicas de Cultura de Tecidos , Transcriptoma , Resultado do Tratamento
3.
J Gastroenterol Hepatol ; 37(3): 531-541, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34931384

RESUMO

BACKGROUND AND AIM: Anti-tumor necrosis factor-α (anti-TNF-α) agents have been used for inflammatory bowel disease; however, it has up to 30% nonresponse rate. Identifying molecular pathways and finding reliable diagnostic biomarkers for patient response to anti-TNF-α treatment are needed. METHODS: Publicly available transcriptomic data from inflammatory bowel disease patients receiving anti-TNF-α therapy were systemically collected and integrated. In silico flow cytometry approaches and Metascape were applied to evaluate immune cell populations and to perform gene enrichment analysis, respectively. Genes identified within enrichment pathways validated in neutrophils were tracked in an anti-TNF-α-treated animal model (with lipopolysaccharide-induced inflammation). The receiver operating characteristic curve was applied to all genes to identify the best prediction biomarkers. RESULTS: A total of 449 samples were retrieved from control, baseline, and after primary anti-TNF-α therapy or placebo. No statistically significant differences were observed between anti-TNF-α treatment responders and nonresponders at baseline in immune microenvironment scores. Neutrophil, endothelial cell, and B-cell populations were higher in baseline nonresponders, and chemotaxis pathways may contribute to the treatment resistance. Genes related to chemotaxis pathways were significantly upregulated in lipopolysaccharide-induced neutrophils, but no statistically significant changes were observed in neutrophils treated with anti-TNF-α. Interleukin 13 receptor subunit alpha 2 (IL13RA2) is the best predictor (receiver operating characteristic curve: 80.7%, 95% confidence interval: 73.8-87.5%), with a sensitivity of 68.13% and specificity of 84.93%, and significantly higher in nonresponders compared with responders (P < 0.0001). CONCLUSIONS: Hyperactive neutrophil chemotaxis influences responses to anti-TNF-α treatment, and IL13RA2 is a potential biomarker to predict anti-TNF-α treatment response.


Assuntos
Quimiotaxia , Doenças Inflamatórias Intestinais , Neutrófilos , Inibidores do Fator de Necrose Tumoral , Animais , Quimiotaxia/fisiologia , Resistência a Medicamentos , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Neutrófilos/fisiologia , Inibidores do Fator de Necrose Tumoral/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/efeitos dos fármacos
4.
Int J Mol Sci ; 22(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921348

RESUMO

Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18-25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes' expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment.


Assuntos
Carcinogênese/genética , Colite/genética , Neoplasias Colorretais/genética , MicroRNAs/genética , Colite/complicações , Colite/patologia , Neoplasias Colorretais/complicações , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos
5.
Gut ; 69(7): 1248-1257, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31776231

RESUMO

OBJECTIVE: There is a need for early detection of colorectal cancer (CRC) at precancerous-stage adenoma. Here, we identified novel faecal bacterial markers for diagnosing adenoma. DESIGN: This study included 1012 subjects (274 CRC, 353 adenoma and 385 controls) from two independent Asian groups. Candidate markers were identified by metagenomics and validated by targeted quantitative PCR. RESULTS: Metagenomic analysis identified 'm3' from a Lachnoclostridium sp., Fusobacterium nucleatum (Fn) and Clostridium hathewayi (Ch) to be significantly enriched in adenoma. Faecal m3 and Fn were significantly increased from normal to adenoma to CRC (p<0.0001, linear trend by one-way ANOVA) in group I (n=698), which was further confirmed in group II (n=313; p<0.0001). Faecal m3 may perform better than Fn in distinguishing adenoma from controls (areas under the receiver operating characteristic curve (AUROCs) m3=0.675 vs Fn=0.620, p=0.09), while Fn performed better in diagnosing CRC (AUROCs Fn=0.862 vs m3=0.741, p<0.0001). At 78.5% specificity, m3 and Fn showed sensitivities of 48.3% and 33.8% for adenoma, and 62.1% and 77.8% for CRC, respectively. In a subgroup tested with faecal immunochemical test (FIT; n=642), m3 performed better than FIT in detecting adenoma (sensitivities for non-advanced and advanced adenomas of 44.2% and 50.8% by m3 (specificity=79.6%) vs 0% and 16.1% by FIT (specificity=98.5%)). Combining with FIT improved sensitivity of m3 for advanced adenoma to 56.8%. The combination of m3 with Fn, Ch, Bacteroides clarus and FIT performed best for diagnosing CRC (specificity=81.2% and sensitivity=93.8%). CONCLUSION: This study identifies a novel bacterial marker m3 for the non-invasive diagnosis of colorectal adenoma.


Assuntos
Adenoma/diagnóstico , Clostridiales/metabolismo , Neoplasias Colorretais/diagnóstico , Fezes/microbiologia , Biomarcadores Tumorais/análise , Estudos de Casos e Controles , Fezes/química , Feminino , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
6.
RNA Biol ; 17(3): 395-402, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31905034

RESUMO

In the present study, we applied our 'precise annotation' to the mitochondrial (mt) genomes of human, chimpanzee, rhesus macaque and mouse using 5' and 3' end small RNAs. Our new annotations updated previous annotations. In particular, our new annotations led to two important novel findings: (1) the identification of five Conserved Sequence Blocks (CSB1, CSB2, CSB3, LSP and HSP) in the control regions; and (2) the annotation of Transcription Initiation and novel Transcription Termination Sites. Based on these annotations, we proposed a novel model of mt transcription which can account for the mt transcription and its regulation in mammals. According to our model, Transcription Termination Sites function as switches to regulate the production of short, long primary transcripts and uninterrupted transcription, rather than simply terminate the mt transcription. Moreover, the expression levels of mitochondrial transcription termination factors control the proportions of rRNAs, mRNAs and lncRNAs in total mt RNA. Our findings point to the existence of many other, as yet unidentified, Transcription Termination Sites in mammals.


Assuntos
Genoma Mitocondrial , Macaca mulatta/genética , Pan troglodytes/genética , Animais , Sequência de Bases , Sequência Conservada , Genes Mitocondriais , Genoma Humano , Humanos , Mamíferos/genética , Camundongos , Anotação de Sequência Molecular , RNA Antissenso , Sítio de Iniciação de Transcrição , Transcrição Gênica
7.
BMC Genomics ; 20(1): 173, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30836939

RESUMO

BACKGROUND: With the unprecedented rapid growth rate (up to 2.75 cm/day), velvet antler is an invaluable model for the identification of potent growth factors and signaling networks for extremely fast growing tissues, mainly cartilage. Antler growth center (AGC) locates in its tip and consists of five tissue layers: reserve mesenchyme (RM), precartilage (PC), transition zone (TZ), cartilage (CA) and mineralized cartilage (MC). The aim of this study was to investigate the transcription dynamics in the AGC using RNA-seq technology. RESULTS: Five tissue layers in the AGC were collected from three 3-year-old male sika deer using our previously reported sampling method (morphologically distinguishable). After sequencing (15 samples; triplicates/tissue layer), we assembled a reference transcriptome de novo and used RNA-seq to measure gene expression profiles across these five layers. Nine differentially expressed genes (DEGs) were selected from our data and subsequently verified using qRT-PCR. The results showed a high consistency with the RNA-seq results (R2 = 0.80). Nine modules were constructed based on co-expression network analysis, and these modules contained 370 hub genes. These genes were found to be mainly involved in mesenchymal progenitor cell proliferation, chondrogenesis, osteogenesis and angiogenesis. Combination of our own results with the previously published reports, we found that Wnt signaling likely plays a key role not only in stimulating the antler stem cells or their immediate progeny, but also in promoting chondrogenesis and osteogenesis during antler development. CONCLUSION: We have successfully assembled a reference transcriptome, generated gene expression profiling across the five tissue layers in the AGC, and identified nine co-expressed modules that contain 370 hub genes and genes predorminantly expressed in and highly relevant to each tissue layer. We believe our findings have laid the foundation for the identification of novel genes for rapid proliferation and chondrogenic differentiation of antler cells.


Assuntos
Diferenciação Celular/genética , Cervos/genética , Perfilação da Expressão Gênica , Transcriptoma/genética , Animais , Chifres de Veado/crescimento & desenvolvimento , Cartilagem/crescimento & desenvolvimento , Condrogênese/genética , Cervos/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , Especificidade de Órgãos/genética , Osteogênese/genética
8.
J Nerv Ment Dis ; 207(4): 271-276, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30844940

RESUMO

This cross-sectional study aimed at measuring the correlation and association between serum levels of cortisol, inflammatory cytokines, and depression and to measure the detection accuracy of serum levels of cortisol in serum samples. In total, 89 male participants were recruited into this study from June 15, 2017, to September 31, 2017. The Hamilton Depression Rating Scale, Beck Anxiety Inventory, and Pittsburgh Sleep Quality Index were used to investigate the mental health status of the participants. Serum concentrations of cortisol and inflammatory cytokines were determined. The serum cortisol concentration, anxiety level, and sleep quality were included in the final logistic regression model. Serum cortisol was able to accurately distinguish between patients with depression and those without depression. There was a significant positive correlation between serum cortisol levels and Hamilton Depression Rating Scale scores.


Assuntos
Citocinas/sangue , Depressão/sangue , Transtorno Depressivo/sangue , Hidrocortisona/sangue , Adulto , Biomarcadores/sangue , Estudos Transversais , Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
9.
J Clin Nurs ; 28(9-10): 1839-1846, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30667111

RESUMO

AIMS AND OBJECTIVES: To compare persistence and outcomes of non-vitamin K antagonist oral anticoagulants (NOACs) versus warfarin in Chinese patients with non-valvular atrial fibrillation (AF). BACKGROUND: Given the unpredictable warfarin response and the costliness of NOACs, more research is needed to clarify which drug enjoys better persistence and outcomes, helping to provide personalised care for patients. DESIGN: A prospective cohort study. METHODS: Chinese patients taking NOACs or warfarin from March 2016-April 2018 were followed up by telephone or outpatient visit at 3, 6 months and half a year thereafter. Anticoagulant persistence and outcomes including stroke and bleeding were collected. We used Cox regression to analyse data. This study was reported according to the STROBE guideline. RESULTS: A total of 344 patients were enrolled; 146 patients received NOACs including dabigatran and rivaroxaban, and 198 patients received warfarin. Persistence with anticoagulants was low and dropped sharply at the third month. Patients on NOACs had worse persistence at 3, 6 and 12 months than those on warfarin. There was no difference in the incidence of ischaemic stroke and bleeding between groups, although ischaemic stroke and major bleeding occurred less frequently in the NOACs group. Paroxysmal AF, no heart failure and no stroke were predictors of NOACs non-persistence. Prior catheter ablation and no diabetes were associated with poor persistence of warfarin. The main reason for anticoagulant cessation was patient preference. CONCLUSIONS: Chinese patients taking NOACs had lower persistence, similar rate of ischaemic stroke and bleeding compared with those on warfarin. Further inventions are needed to improve persistence in Chinese patients on NOACs. RELEVANCE TO CLINICAL PRACTICE: Anticoagulation should highlight both persistence and outcomes emphasising personalised care of different drugs. Further interventions to improve persistence should be developed based on causes and risk factors and carried out in the third month of therapy.


Assuntos
Anticoagulantes/administração & dosagem , Fibrilação Atrial/tratamento farmacológico , Dabigatrana/administração & dosagem , Inibidores do Fator Xa/administração & dosagem , Adesão à Medicação/estatística & dados numéricos , Rivaroxabana/administração & dosagem , Varfarina/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Dabigatrana/efeitos adversos , Inibidores do Fator Xa/efeitos adversos , Feminino , Hemorragia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Preferência do Paciente , Estudos Prospectivos , Rivaroxabana/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Varfarina/efeitos adversos
10.
Gut ; 66(1): 70-78, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26408641

RESUMO

OBJECTIVE: To evaluate the potential for diagnosing colorectal cancer (CRC) from faecal metagenomes. DESIGN: We performed metagenome-wide association studies on faecal samples from 74 patients with CRC and 54 controls from China, and validated the results in 16 patients and 24 controls from Denmark. We further validated the biomarkers in two published cohorts from France and Austria. Finally, we employed targeted quantitative PCR (qPCR) assays to evaluate diagnostic potential of selected biomarkers in an independent Chinese cohort of 47 patients and 109 controls. RESULTS: Besides confirming known associations of Fusobacterium nucleatum and Peptostreptococcus stomatis with CRC, we found significant associations with several species, including Parvimonas micra and Solobacterium moorei. We identified 20 microbial gene markers that differentiated CRC and control microbiomes, and validated 4 markers in the Danish cohort. In the French and Austrian cohorts, these four genes distinguished CRC metagenomes from controls with areas under the receiver-operating curve (AUC) of 0.72 and 0.77, respectively. qPCR measurements of two of these genes accurately classified patients with CRC in the independent Chinese cohort with AUC=0.84 and OR of 23. These genes were enriched in early-stage (I-II) patient microbiomes, highlighting the potential for using faecal metagenomic biomarkers for early diagnosis of CRC. CONCLUSIONS: We present the first metagenomic profiling study of CRC faecal microbiomes to discover and validate microbial biomarkers in ethnically different cohorts, and to independently validate selected biomarkers using an affordable clinically relevant technology. Our study thus takes a step further towards affordable non-invasive early diagnostic biomarkers for CRC from faecal samples.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais/diagnóstico , Disbiose/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Idoso , Área Sob a Curva , Áustria , Estudos de Casos e Controles , China , Estudos de Coortes , Neoplasias Colorretais/complicações , Dinamarca , Disbiose/complicações , Feminino , Firmicutes/isolamento & purificação , França , Fusobacterium nucleatum/isolamento & purificação , Estudo de Associação Genômica Ampla , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Peptostreptococcus/isolamento & purificação , Curva ROC
11.
Gastroenterology ; 147(6): 1350-62.e4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25173755

RESUMO

BACKGROUND & AIMS: The mechanisms by which Epstein-Barr virus (EBV) contributes to the development of gastric cancer are unclear. We investigated EBV-associated genomic and epigenomic variations in gastric cancer cells and tumors. METHODS: We performed whole-genome, transcriptome, and epigenome sequence analyses of a gastric adenocarcinoma cell line (AGS cells), before and after EBV infection. We then looked for alterations in gastric tumor samples, with (n = 34) or without (n = 100) EBV infection, collected from patients at the Prince of Wales Hospital, Chinese University of Hong Kong (from 1998 through 2004), or the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China (from 1999 through 2006). RESULTS: Transcriptome analysis showed that infected cells expressed 9 EBV genes previously detected in EBV-associated gastric tumors and 71 EBV genes not previously reported in gastric tumors. Ten viral genes that had not been reported previously in gastric cancer but were expressed most highly in EBV-infected cells also were expressed in primary EBV-positive gastric tumors. Whole-genome sequence analysis identified 45 EBV-associated nonsynonymous mutations. These mutations, in genes such as AKT2, CCNA1, MAP3K4, and TGFBR1, were associated significantly with EBV-positive gastric tumors, compared with EBV-negative tumors. An activating mutation in AKT2 was associated with reduced survival times of patients with EBV-positive gastric cancer (P = .006); this mutation was found to dysregulate mitogen-activated protein kinase signaling. Integrated epigenome and transcriptome analyses identified 216 genes transcriptionally down-regulated by EBV-associated hypermethylation; methylation of ACSS1, FAM3B, IHH, and TRABD increased significantly in EBV-positive tumors. Overexpression of Indian hedgehog (IHH) and TraB domain containing (TRABD) increased proliferation and colony formation of gastric cancer cells, whereas knockdown of these genes reduced these activities. We found 5 signaling pathways (axon guidance, focal adhesion formation, interactions among cytokines and receptors, mitogen-activated protein kinase signaling, and actin cytoskeleton regulation) to be affected commonly by EBV-associated genomic and epigenomic alterations. CONCLUSIONS: By using genomic, transcriptome, and epigenomic comparisons of EBV infected vs noninfected gastric cancer cells and tumor samples, we identified alterations in genes, gene expression, and methylation that affect different signaling networks. These might be involved in EBV-associated gastric carcinogenesis.


Assuntos
Adenocarcinoma/genética , Infecções por Vírus Epstein-Barr/genética , Estudo de Associação Genômica Ampla , Herpesvirus Humano 4/genética , Neoplasias Gástricas/genética , Transcriptoma , Adenocarcinoma/virologia , Linhagem Celular Tumoral , Ciclina A1/genética , Metilação de DNA/genética , Epigênese Genética/genética , Infecções por Vírus Epstein-Barr/virologia , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Genes Virais , Humanos , MAP Quinase Quinase Quinase 4/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/genética , Neoplasias Gástricas/virologia
12.
J Hepatol ; 61(6): 1365-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25048951

RESUMO

BACKGROUND & AIMS: Perpetuate liver inflammation is crucial in the pathogenesis of non-alcoholic steatohepatitis (NASH). Expression of CXCL10, a pro-inflammatory cytokine, correlates positively with obesity and type 2 diabetes. Whether CXCL10 plays a role in NASH was unknown. We aimed to investigate the functional and clinical impact of CXCL10 in NASH. METHODS: Cxcl10 gene-deleted (Cxcl10(-/-)) and C57BL/6 wild type (WT) mice were fed a methionine- and choline-deficient (MCD) diet for 4 or 8 weeks. In other experiments, we injected neutralizing anti-CXCL10 mAb into MCD-fed WT mice. Human serum was obtained from 147 patients with biopsy-proven non-alcoholic fatty liver disease and 73 control subjects. RESULTS: WT mice, fed the MCD diet, developed steatohepatitis with higher hepatic CXCL10 expression. Cxcl10(-/-) mice were refractory to MCD-induced steatohepatitis. We further revealed that CXCL10 was associated with the induction of important pro-inflammatory cytokines (TNF-α, IL-1ß, and MCP-1) and activation of the NF-κB pathway. CXCL10 was linked to steatosis through upregulation of the lipogenic factors SREBP-1c and LXR, and also to oxidative stress (upregulation of CYP2E1 and C/EBPß). Blockade of CXCL10 protected against hepatocyte injury in vitro and against steatohepatitis development in mice. We further investigated the clinical impact of CXCL10 and found circulating and hepatic CXCL10 levels were significantly higher in human NASH. Importantly, the circulating CXCL10 level was correlated with the degree of lobular inflammation and was an independent risk factor for NASH patients. CONCLUSIONS: We demonstrate for the first time that CXCL10 plays a pivotal role in the pathogenesis of experimental steatohepatitis. CXCL10 maybe a potential non-invasive biomarker for NASH patients.


Assuntos
Quimiocina CXCL10/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Biomarcadores/metabolismo , Biópsia , Estudos de Casos e Controles , Quimiocina CXCL10/deficiência , Quimiocina CXCL10/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Transdução de Sinais/fisiologia
13.
Gastro Hep Adv ; 3(5): 687-702, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165427

RESUMO

Background and Aims: Decoding pancreatic ductal adenocarcinoma heterogeneity and the consequent therapeutic selection remains a challenge. We aimed to characterize epigenetically regulated pathways involved in pancreatic ductal adenocarcinoma progression. Methods: Global DNA methylation analysis in pancreatic cancer patient tissues and cell lines was performed to identify differentially methylated genes. Targeted bisulfite sequencing and in vitro methylation reporter assays were employed to investigate the direct link between site-specific methylation and transcriptional regulation. A series of in vitro loss-of-function and gain-of function studies and in vivo xenograft and the KPC (LSL-Kras G12D/+ ; LSL-Trp53 R172H/+ ; Pdx1-Cre) mouse models were used to assess pancreatic cancer cell properties. Gene and protein expression analyses were performed in 3 different cohorts of pancreatic cancer patients and correlated to clinicopathological parameters. Results: We identify Hepatocyte Nuclear Factor 4A (HNF4A) as a novel target of hypermethylation in pancreatic cancer and demonstrate that site-specific proximal promoter methylation drives HNF4A transcriptional repression. Expression analyses in patients indicate the methylation-associated suppression of HNF4A expression in pancreatic cancer tissues. In vitro and in vivo studies reveal that HNF4A is a novel tumor suppressor in pancreatic cancer, regulating cancer growth and aggressiveness. As evidenced in both the KPC mouse model and human pancreatic cancer tissues, HNF4A expression declines significantly in the early stages of the disease. Most importantly, HNF4 loss correlates with poor overall patient survival. Conclusion: HNF4A silencing, mediated by promoter DNA methylation, drives pancreatic cancer development and aggressiveness leading to poor patient survival.

14.
World J Gastroenterol ; 29(22): 3385-3399, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37389232

RESUMO

Clostridioides difficile (formerly called Clostridium difficile, C. difficile) infection (CDI) is listed as an urgent threat on the 2019 antibiotic resistance threats report in the United States by the Centers for Disease Control and Prevention. Early detection and appropriate disease management appear to be essential. Meanwhile, although the majority of cases are hospital-acquired CDI, community-acquired CDI cases are also on the rise, and this vulnerability is not limited to immunocompromised patients. Gastrointestinal treatments and/or gastrointestinal tract surgeries may be required for patients diagnosed with digestive diseases. Such treatments could suppress or interfere with the patient's immune system and disrupt gut flora homeostasis, creating a suitable microecosystem for C. difficile overgrowth. Currently, stool-based non-invasive screening is the first-line approach to CDI diagnosis, but the accuracy is varied due to different clinical microbiology detection methods; therefore, improving reliability is clearly required. In this review, we briefly summarised the life cycle and toxicity of C. difficile, and we examined existing diagnostic approaches with an emphasis on novel biomarkers such as microRNAs. These biomarkers can be easily detected through non-invasive liquid biopsy and can yield crucial information about ongoing pathological phenomena, particularly in CDI.


Assuntos
Clostridioides difficile , Infecções por Clostridium , MicroRNAs , Humanos , Clostridioides difficile/genética , Reprodutibilidade dos Testes , Infecções por Clostridium/diagnóstico , Fezes
15.
Front Microbiol ; 14: 1141495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876116

RESUMO

Background: Identification of transposons without close homologs is still a difficult task. IS630/Tc1/mariner transposons, classified into a superfamily, are probably the most widespread DNA transposons in nature. Tc1/mariner transposons have been discovered in animals, plants, and filamentous fungi, however, not in yeast. Results: In the present study, we report the discovery of two intact Tc1 transposons in yeast and filamentous fungi, respectively. The first one, named Tc1-OP1 (DD40E), represents Tc1 transposons in Ogataea parapolymorpha. The second one, named Tc1-MP1 (DD34E), represents Tc1 transposons in the Rhizopodaceae and Mucoraceae families. As a homolog of Tc1-OP1 and Tc1-MP1, IS630-AB1 (DD34E) was discovered as an IS630 transposon in Acinetobacter spp. Conclusion: Tc1-OP1 is not only the first reported Tc1 transposon in yeast, but also the first reported nonclassical Tc1 transposon. Tc1-OP1 is the largest of IS630/Tc1/mariner transposons reported to date and significantly different from others. Notably, Tc1-OP1 encodes a serine-rich domain and a transposase, extending the current knowledge of Tc1 transposons. The phylogenetic relationships of Tc1-OP1, Tc1-MP1 and IS630-AB1 indicated that these transposons had evolved from a common ancestor. Tc1-OP1, Tc1-MP1 and IS630-AB1 can be used as reference sequences to facilitate the identification of IS630/Tc1/mariner transposons. More Tc1/mariner transposons will be identified in yeast, following our discovery.

16.
Front Microbiol ; 13: 855666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464988

RESUMO

Background: Currently, methylotrophic yeasts (e.g., Pichia pastoris, Ogataea polymorpha, and Candida boindii) are subjects of intense genomics studies in basic research and industrial applications. In the genus Ogataea, most research is focused on three basic O. polymorpha strains-CBS4732, NCYC495, and DL-1. However, the relationship between CBS4732, NCYC495, and DL-1 remains unclear, as the genomic differences between them have not be exactly determined without their high-quality complete genomes. As a nutritionally deficient mutant derived from CBS4732, the O. polymorpha strain CBS4732 ura3Δ (named HU-11) is being used for high-yield production of several important proteins or peptides. HU-11 has the same reference genome as CBS4732 (noted as HU-11/CBS4732), because the only genomic difference between them is a 5-bp insertion. Results: In the present study, we have assembled the full-length genome of O. polymorpha HU-11/CBS4732 using high-depth PacBio and Illumina data. Long terminal repeat retrotransposons (LTR-rts), rDNA, 5' and 3' telomeric, subtelomeric, low complexity and other repeat regions were exactly determined to improve the genome quality. In brief, the main findings include complete rDNAs, complete LTR-rts, three large duplicated segments in subtelomeric regions and three structural variations between the HU-11/CBS4732 and NCYC495 genomes. These findings are very important for the assembly of full-length genomes of yeast and the correction of assembly errors in the published genomes of Ogataea spp. HU-11/CBS4732 is so phylogenetically close to NCYC495 that the syntenic regions cover nearly 100% of their genomes. Moreover, HU-11/CBS4732 and NCYC495 share a nucleotide identity of 99.5% through their whole genomes. CBS4732 and NCYC495 can be regarded as the same strain in basic research and industrial applications. Conclusion: The present study preliminarily revealed the relationship between CBS4732, NCYC495, and DL-1. Our findings provide new opportunities for in-depth understanding of genome evolution in methylotrophic yeasts and lay the foundations for the industrial applications of O. polymorpha CBS4732, NCYC495, DL-1, and their derivative strains. The full-length genome of O. polymorpha HU-11/CBS4732 should be included into the NCBI RefSeq database for future studies of Ogataea spp.

17.
J Clin Invest ; 132(21)2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36099049

RESUMO

BackgroundImmune exhaustion and senescence are dominant dysfunctional states of effector T cells and major hurdles for the success of cancer immunotherapy. In the current study, we characterized how acute myeloid leukemia (AML) promotes the generation of senescent-like CD8+ T cells and whether they have prognostic relevance.METHODSWe analyzed NanoString, bulk RNA-Seq and single-cell RNA-Seq data from independent clinical cohorts comprising 1,896 patients treated with chemotherapy and/or immune checkpoint blockade (ICB).ResultsWe show that senescent-like bone marrow CD8+ T cells were impaired in killing autologous AML blasts and that their proportion negatively correlated with overall survival (OS). We defined what we believe to be new immune effector dysfunction (IED) signatures using 2 gene expression profiling platforms and reported that IED scores correlated with adverse-risk molecular lesions, stemness, and poor outcomes; these scores were a more powerful predictor of OS than 2017-ELN risk or leukemia stem cell (LSC17) scores. IED expression signatures also identified an ICB-unresponsive tumor microenvironment and predicted significantly shorter OS.ConclusionThe IED scores provided improved AML-risk stratification and could facilitate the delivery of personalized immunotherapies to patients who are most likely to benefit.TRIAL REGISTRATIONClinicalTrials.gov; NCT02845297.FUNDINGJohn and Lucille van Geest Foundation, Nottingham Trent University's Health & Wellbeing Strategic Research Theme, NIH/NCI P01CA225618, Genentech-imCORE ML40354, Qatar National Research Fund (NPRP8-2297-3-494).


Assuntos
Doenças do Sistema Imunitário , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico , Prognóstico , Imunoterapia , Microambiente Tumoral , Linfócitos T CD8-Positivos
18.
Clin Respir J ; 15(2): 163-168, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32975905

RESUMO

BACKGROUND: Erectile dysfunction (ED) with obstructive sleep apnoea (OSA) is a relatively common issue for men. A number of clinical studies have demonstrated that continuous positive airway pressure (CPAP) therapy may effectively alleviate ED symptoms from patients with OSA. METHODS: PubMed, MEDLINE, EMBASE and Cochrane Library databases were utilised and searched for the relevant studies up to September 2, 2019. The International Index of Erectile Function 5 (IIEF-5) scoring system from the patients before and after receiving their CPAP therapy were collected according to the strict inclusion and exclusion criteria. REVMEN 5.3 software was applied for the meta-analysis. RESULTS: A total of seven publications consisted of 206 ED patients with OSA were included in the study. ED patients with OSA received CPAP treatment were significantly improved based on the IIEF-5 scores [Weighted Mean Difference (WMD) = 1.14, 95% confidence interval (CI) = 0.89-1.38, z = 9.09, p < 0.0001].Our research found that the high heterogeneity is mainly due to Zhang's data, with a higher apnoea-hypopnea index (AHI) compared to the other included studies. A moderate heterogeneity (I2 = 54%, P = 0.05) was found after removal of Zhang's data. CONCLUSION: The results suggest that continuous positive airway pressure therapy relive erectile dysfunction symptoms in patients with obstructive sleep apnoea. However, further evidence is needed due to the insufficient number of included patients and high heterogeneity.


Assuntos
Disfunção Erétil , Apneia Obstrutiva do Sono , Pressão Positiva Contínua nas Vias Aéreas , Disfunção Erétil/terapia , Humanos , Masculino , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/terapia
19.
Front Microbiol ; 12: 614494, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815307

RESUMO

In December 2019, the world awoke to a new betacoronavirus strain named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Betacoronavirus consists of A, B, C and D subgroups. Both SARS-CoV and SARS-CoV-2 belong to betacoronavirus subgroup B. In the present study, we divided betacoronavirus subgroup B into the SARS1 and SARS2 classes by six key insertions and deletions (InDels) in betacoronavirus genomes, and identified a recently detected betacoronavirus strains RmYN02 as a recombinant strain across the SARS1 and SARS2 classes, which has potential to generate a new strain with similar risk as SARS-CoV and SARS-CoV-2. By analyzing genomic features of betacoronavirus, we concluded: (1) the jumping transcription and recombination of CoVs share the same molecular mechanism, which inevitably causes CoV outbreaks; (2) recombination, receptor binding abilities, junction furin cleavage sites (FCSs), first hairpins and ORF8s are main factors contributing to extraordinary transmission, virulence and host adaptability of betacoronavirus; and (3) the strong recombination ability of CoVs integrated other main factors to generate multiple recombinant strains, two of which evolved into SARS-CoV and SARS-CoV-2, resulting in the SARS and COVID-19 pandemics. As the most important genomic features of SARS-CoV and SARS-CoV-2, an enhanced ORF8 and a novel junction FCS, respectively, are indispensable clues for future studies of their origin and evolution. The WIV1 strain without the enhanced ORF8 and the RaTG13 strain without the junction FCS "RRAR" may contribute to, but are not the immediate ancestors of SARS-CoV and SARS-CoV-2, respectively.

20.
Microorganisms ; 9(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34361920

RESUMO

BACKGROUND: Non-communicable diseases (NCDs) have become a major cause of morbidity and mortality in India. Perturbation of host-microbiome interactions may be a key mechanism by which lifestyle-related risk factors such as tobacco use, alcohol consumption, and physical inactivity may influence metabolic health. There is an urgent need to identify relevant dysmetabolic traits for predicting risk of metabolic disorders, such as diabetes, among susceptible Asian Indians where NCDs are a growing epidemic. METHODS: Here, we report the first in-depth phenotypic study in which we prospectively enrolled 218 adults from urban and rural areas of Central India and used multiomic profiling to identify relationships between microbial taxa and circulating biomarkers of cardiometabolic risk. Assays included fecal microbiota analysis by 16S ribosomal RNA gene amplicon sequencing, quantification of serum short chain fatty acids by gas chromatography-mass spectrometry, and multiplex assaying of serum diabetic proteins, cytokines, chemokines, and multi-isotype antibodies. Sera was also analysed for N-glycans and immunoglobulin G Fc N-glycopeptides. RESULTS: Multiple hallmarks of dysmetabolism were identified in urbanites and young overweight adults, the majority of whom did not have a known diagnosis of diabetes. Association analyses revealed several host-microbe and metabolic associations. CONCLUSIONS: Host-microbe and metabolic interactions are differentially shaped by body weight and geographic status in Central Indians. Further exploration of these links may help create a molecular-level map for estimating risk of developing metabolic disorders and designing early interventions.

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