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1.
Benef Microbes ; 13(6): 465-471, 2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36264094

ABSTRACT

Body mass index (BMI) and gut microbiota show significant interaction, but most studies on the relationship between BMI and gut microbiota have been done in Western countries. Relationships that are also identified in other cultural backgrounds are likely to have functional importance. Hence here we explore gut microbiota in adults living in Xining city (China P.R.) and relate results to subject BMI. Analysis of bacterial 16s rRNA gene was performed on faecal samples from participants with normal-weight (n=24), overweight (n=24), obesity (n=11) and type 2 diabetes (T2D) (n=8). The results show that unweighted but not weighted Unifrac distance was significantly different when gut microbiota composition was compared between the groups. Importantly, the genus Streptococcus was remarkably decreased in both obese subjects and subjects suffering from T2D, as compared to normal-weight subjects. Accordingly, strong association was identified between the genus Streptococcus and BMI and especially Streptococcus salivarius subsp. thermophiles was a major contributor in this respect. As previous studies have shown that Streptococcus salivarius subsp. thermophiles is also negatively associated with obesity in Western cohorts, our results suggest that this species is a potential probiotic for the prevention of obesity and related disorders.


Subject(s)
Diabetes Mellitus, Type 2 , Probiotics , Humans , Body Mass Index , RNA, Ribosomal, 16S/genetics , Streptococcus/genetics , Obesity
2.
Pancreatology ; 22(7): 973-986, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35864067

ABSTRACT

BACKGROUND AND AIMS: Pancreatic cancer has a dismal prognosis. So far, imaging has been proven incapable of establishing an early enough diagnosis. Thus, biomarkers are urgently needed for early detection and improved survival. Our aim was to evaluate the pooled diagnostic performance of DNA alterations in pancreatic juice. METHODS: A systematic literature search was performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL and Web of Science for studies concerning the diagnostic performance of DNA alterations in pancreatic juice to differentiate patients with high-grade dysplasia or pancreatic cancer from controls. Study quality was assessed using QUADAS-2. The pooled prevalence, sensitivity, specificity and diagnostic odds ratio were calculated. RESULTS: Studies mostly concerned cell-free DNA mutations (32 studies: 939 cases, 1678 controls) and methylation patterns (14 studies: 579 cases, 467 controls). KRAS, TP53, CDKN2A, GNAS and SMAD4 mutations were evaluated most. Of these, TP53 had the highest diagnostic performance with a pooled sensitivity of 42% (95% CI: 31-54%), specificity of 98% (95%-CI: 92%-100%) and diagnostic odds ratio of 36 (95% CI: 9-133). Of DNA methylation patterns, hypermethylation of CDKN2A, NPTX2 and ppENK were studied most. Hypermethylation of NPTX2 performed best with a sensitivity of 39-70% and specificity of 94-100% for distinguishing pancreatic cancer from controls. CONCLUSIONS: This meta-analysis shows that, in pancreatic juice, the presence of distinct DNA mutations (TP53, SMAD4 or CDKN2A) and NPTX2 hypermethylation have a high specificity (close to 100%) for the presence of high-grade dysplasia or pancreatic cancer. However, the sensitivity of these DNA alterations is poor to moderate, yet may increase if they are combined in a panel.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Biomarkers, Tumor/genetics , Biomarkers, Tumor/analysis , Carcinoma, Pancreatic Ductal/diagnosis , Early Detection of Cancer , Mutation , Pancreatic Juice/chemistry , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms
3.
Gut Microbes ; 14(1): 2015238, 2022.
Article in English | MEDLINE | ID: mdl-34965181

ABSTRACT

Autophagy is a cellular degradation mechanism, which is triggered by the bacterium Helicobacter pylori. A single nucleotide polymorphism (SNP) in the autophagy gene ATG16L1 (rs2241880, G-allele) has been shown to dysregulate autophagy and increase intestinal endoplasmic reticulum (ER) stress. Here, we investigate the role of this SNP in H.pylori-mediated gastric carcinogenesis and its molecular pathways. ATG16L1 rs2241880 was genotyped in subjects from different ethnic cohorts (Dutch and Australian) presenting with gastric (pre)malignant lesions of various severity. Expression of GRP78 (a marker for ER stress) was assessed in gastric tissues. The effect of ATG16L1 rs2241880 on H.pylori-mediated ER stress and pro-inflammatory cytokine induction was investigated in organoids and CRISPR/Cas9 modified cell lines. Development of gastric cancer was associated with the ATG16L1 rs2241880 G-allele. Intestinal metaplastic cells in gastric tissue of patients showed increased levels of ER-stress. In vitro models showed that H.pylori increases autophagy while reducing ER stress, which appeared partly mediated by the ATG16L1 rs2241880 genotype. H.pylori-induced IL-8 production was increased while TNF-α production was decreased, in cells homozygous for the G-allele. The ATG16L1 rs2241880 G-allele is associated with progression of gastric premalignant lesions and cancer. Modulation of H.pylori-induced ER stress pathways and pro-inflammatory mediators by ATG16L1 rs2441880 may underlie this increased risk.


Subject(s)
Autophagy , Endoplasmic Reticulum Stress , Helicobacter Infections/physiopathology , Helicobacter pylori/physiology , Stomach Neoplasms/physiopathology , Adult , Aged , Australia , Autophagy-Related Proteins/genetics , Autophagy-Related Proteins/metabolism , Cohort Studies , Disease Progression , Female , Gastrointestinal Microbiome , Helicobacter Infections/genetics , Helicobacter Infections/metabolism , Helicobacter Infections/microbiology , Humans , Male , Middle Aged , Netherlands , Polymorphism, Single Nucleotide , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Stomach Neoplasms/microbiology
4.
Gastric Cancer ; 25(2): 375-381, 2022 03.
Article in English | MEDLINE | ID: mdl-34792700

ABSTRACT

BACKGROUND: Gastric and colorectal cancer (CRC) are both one of the most common cancers worldwide. In many countries fecal immunochemical tests (FIT)-based CRC screening has been implemented. We investigated if FIT can also be applied for detection of H. pylori, the main risk factor for gastric cancer. METHODS: This prospective study included participants over 18 years of age referred for urea breath test (UBT). Patients were excluded if they had used antibiotics/bismuth in the past 4 weeks, or a proton pomp inhibitor (PPI) in the past 2 weeks. Participants underwent UBT, ELISA stool antigen test in standard feces tube (SAT), ELISA stool antigen test in FIT tube (Hp-FIT), and blood sampling, and completed a questionnaire on user friendliness. UBT results were used as reference. RESULTS: A total of 182 patients were included (37.4% male, median age 52.4 years (IQR 22.4)). Of these, 60 (33.0%) tested H. pylori positive. SAT and Hp-FIT showed comparable overall accuracy 71.1% (95%CI 63.2-78.3) vs. 77.6% (95%CI 70.4-83.8), respectively (p = 0.97). Sensitivity of SAT was 91.8% (95%CI 80.4-97.7) versus 94.2% (95%CI 84.1-98.9) of Hp-FIT (p = 0.98). Serology scored low with an overall accuracy of 49.7% (95%CI 41.7-57.7). Hp-FIT showed the highest overall user convenience. CONCLUSIONS: FIT can be used with high accuracy and sensitivity for diagnosis of H. pylori and is rated as the most convenient test. Non-invasive Hp-FIT test is highly promising for combined upper and lower gastrointestinal (pre-) cancerous screening. Further research should investigate the clinical implications, benefits and cost-effectiveness of such an approach.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Adolescent , Adult , Feces , Female , Helicobacter Infections/diagnosis , Humans , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity
6.
Dis Esophagus ; 33(9)2020 Sep 04.
Article in English | MEDLINE | ID: mdl-32129453

ABSTRACT

Barrett's esophagus (BE) is a metaplastic condition of the distal esophagus, resulting from longstanding gastroesophageal reflux disease (GERD). BE predisposes for the highly malignant esophageal adenocarcinoma (EAC). Both BE and EAC have the highest frequencies in white males. Only a subset of patients with GERD develop BE, while <0.5% of BE will progress to EAC. Therefore, it is most likely that the development of BE and EAC is associated with underlying genetic factors. We hypothesized that in white males, Y-chromosomal haplogroups are associated with BE and EAC. To investigate this we conducted a multicenter study studying the frequencies of the Y-chromosomal haplogroups in GERD, BE, and EAC patients. We used genomic analysis by polymerase chain reaction and restriction fragment length polymorphism to determine the frequency of six Y-chromosomal haplogroups (DE, F(xJ,xK), K(xP), J, P(xR1a), and R1a) between GERD, BE, and EAC in a cohort of 1,365 white males, including 612 GERD, 753 BE patients, while 178 of the BE patients also had BE-associated EAC. Univariate logistic regression analysis was used to compare the outcomes. In this study, we found the R1a (6% vs. 9%, P = 0.04) and K (3% vs. 6%, P = 0.035) to be significantly underrepresented in BE patients as compared to GERD patients with an odds ratio (OR) of 0.63 (95% CI 0.42-0.95, P = 0.03) and of 0.56 (95% CI 0.33-0.96, P = 0.03), respectively, while the K haplogroup was protective against EAC (OR 0.30; 95% CI 0.07-0.86, P = 0.05). A significant overrepresentation of the F haplogroup was found in EAC compared to BE and GERD patients (34% vs. 27% and 23%, respectively). The F haplogroup was found to be a risk factor for EAC with an OR of 1.5 (95% CI 1.03-2.19, P = 0.03). We identified the R1a and K haplogroups as protective factors against development of BE. These haplogroups have low frequencies in white male populations. Of importance is that we could link the presence of the predominantly occurring F haplogroup in white males to EAC. It is possible that this F haplogroup is associated to genetic variants that predispose for the EAC development. In future, the haplogroups could be applied to improve stratification of BE and GERD patients with increased risk to develop BE and/or EAC.


Subject(s)
Adenocarcinoma , Barrett Esophagus , Chromosomes, Human, Y/genetics , Esophageal Neoplasms , Adenocarcinoma/genetics , Barrett Esophagus/genetics , Chromosomes , Esophageal Neoplasms/genetics , Haplotypes , Humans , Male , Risk Factors
7.
Colorectal Dis ; 22(1): 36-45, 2020 01.
Article in English | MEDLINE | ID: mdl-31344302

ABSTRACT

AIM: Anastomotic leakage (AL) is one of the most feared complications after rectal resection. This study aimed to assess a combination of biomarkers for early detection of AL after rectal cancer resection. METHOD: This study was an international multicentre prospective cohort study. All patients received a pelvic drain after rectal cancer resection. On the first three postoperative days drain fluid was collected daily and C-reactive protein (CRP) was measured. Matrix metalloproteinase-2 (MMP2), MMP9, glucose, lactate, interleukin 1-beta (IL1ß), IL6, IL10, tumour necrosis factor alpha (TNFα), Escherichia coli, Enterococcus faecalis, lipopolysaccharide-binding protein and amylase were measured in the drain fluid. Prediction models for AL were built for each postoperative day using multivariate penalized logistic regression. Model performance was estimated by the c-index for discrimination. The model with the best performance was visualized with a nomogram and calibration was plotted. RESULTS: A total of 292 patients were analysed; 38 (13.0%) patients suffered from AL, with a median interval to diagnosis of 6.0 (interquartile ratio 4.0-14.8) days. AL occurred less often after partial than after total mesorectal excision (4.9% vs 15.2%, P = 0.035). Of all patients with AL, 26 (68.4%) required reoperation. AL was more often treated by reoperation in patients without a diverting ileostomy (18/20 vs 8/18, P = 0.03). The prediction model for postoperative day 1 included MMP9, TNFα, diverting ileostomy and surgical technique (c-index = 0.71). The prediction model for postoperative day 2 only included CRP (c-index = 0.69). The prediction model for postoperative day 3 included CRP and MMP9 and obtained the best model performance (c-index = 0.78). CONCLUSION: The combination of serum CRP and peritoneal MMP9 may be useful for earlier prediction of AL after rectal cancer resection. In clinical practice, this combination of biomarkers should be interpreted in the clinical context as with any other diagnostic tool.


Subject(s)
Anastomotic Leak/etiology , Ascitic Fluid/metabolism , Proctectomy/adverse effects , Rectal Neoplasms/surgery , Risk Assessment/methods , Biomarkers/analysis , C-Reactive Protein/analysis , Drainage , Female , Humans , Logistic Models , Male , Matrix Metalloproteinase 9/analysis , Middle Aged , Nomograms , Peritoneum/metabolism , Postoperative Period , Predictive Value of Tests , Prospective Studies , Risk Factors
8.
United European Gastroenterol J ; 7(7): 897-907, 2019 08.
Article in English | MEDLINE | ID: mdl-31428414

ABSTRACT

Background: Homeostasis of the gastrointestinal tract depends on a healthy bacterial microbiota, with alterations in microbiota composition suggested to contribute to diseases. To unravel bacterial contribution to disease pathology, a thorough understanding of the microbiota of the complete gastrointestinal tract is essential. To date, most microbial analyses have either focused on faecal samples, or on the microbial constitution of one gastrointestinal location instead of different locations within one individual. Objective: We aimed to analyse the mucosal microbiome along the entire gastrointestinal tract within the same individuals. Methods: Mucosal biopsies were taken from nine different sites in 14 individuals undergoing antegrade and subsequent retrograde double-balloon enteroscopy. The bacterial composition was characterised using 16 S rRNA sequencing with Illumina Miseq. Results: At double-balloon enteroscopy, one individual had a caecal adenocarcinoma and one individual had Peutz-Jeghers polyps. The composition of the microbiota distinctively changed along the gastrointestinal tract with larger bacterial load, diversity and abundance of Firmicutes and Bacteroidetes in the lower gastrointestinal tract than the upper gastrointestinal tract, which was predominated by Proteobacteria and Firmicutes. Conclusions: We show that gastrointestinal location is a larger determinant of mucosal microbial diversity than inter-person differences. These data provide a baseline for further studies investigating gastrointestinal microbiota-related disease.


Subject(s)
Gastric Mucosa/microbiology , Gastrointestinal Microbiome , Adenocarcinoma/microbiology , Adenocarcinoma/pathology , Adult , Bacterial Load , Biopsy , Cecal Neoplasms/microbiology , Cecal Neoplasms/pathology , Double-Balloon Enteroscopy , Female , Humans , Male , Middle Aged , Peutz-Jeghers Syndrome/microbiology , Peutz-Jeghers Syndrome/pathology , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Sequence Analysis, RNA
9.
Biochim Biophys Acta Rev Cancer ; 1872(2): 188291, 2019 12.
Article in English | MEDLINE | ID: mdl-31059738

ABSTRACT

Idiopathic achalasia and Barrett's esophagus (BE) are preneoplastic conditions of the esophagus. BE increases the risk of esophageal adenocarcinoma (EAC), while achalasia is associated with both EAC and esophageal squamous cell carcinoma (ESCC). However, while the molecular mechanisms underlying the transformation of esophageal epithelial cells in BE are relatively well characterized, less is known regarding these processes in achalasia. Nevertheless, both conditions are associated with chronic inflammation and BE can occur in achalasia patients, and it is likely that similar processes underlie cancer risk in both diseases. The present review will discuss possible lessons that we can learn from the molecular analysis of BE for the study of achalasia-associated cancer and contrast findings in BE with those in achalasia. First, we will describe cellular fate during development of BE, EAC, and ESCC, and consider the inflammatory status of the epithelial barrier in BE and achalasia in terms of its contribution to carcinogenesis. Next, we will summarize current data on genetic alterations and molecular pathways involved in these processes. Lastly, the plausible role of the microbiota in achalasia-associated carcinogenesis and its contribution to abnormal lower esophageal sphincter (LES) functioning, the maintenance of chronic inflammatory status and influence on the esophageal mucosa through carcinogenic by-products, will be discussed.


Subject(s)
Barrett Esophagus/immunology , Esophageal Achalasia/immunology , Esophageal Neoplasms/etiology , Adenocarcinoma/etiology , Adenocarcinoma/genetics , Barrett Esophagus/complications , Barrett Esophagus/genetics , Disease Progression , Esophageal Achalasia/complications , Esophageal Achalasia/genetics , Esophageal Neoplasms/genetics , Esophageal Squamous Cell Carcinoma/etiology , Esophageal Squamous Cell Carcinoma/genetics , Gene Expression Regulation , Gene Regulatory Networks , Genetic Predisposition to Disease , Humans
10.
J Transl Med ; 15(1): 248, 2017 12 11.
Article in English | MEDLINE | ID: mdl-29228965

ABSTRACT

BACKGROUND: The role of single nucleotide polymorphisms (SNPs) associated with inflammatory bowel disease (IBD) is gaining interest. With the advent of novel therapies, personalized treatment in IBD is a future goal. We wondered whether IBD-associated SNPs are able to predict response to anti-TNFα treatment. METHODS: Data on treatment use and primary response, loss of response and side effects to anti-TNFα treatments were retrieved for 570 IBD patients. rs13361189 (IRGM), rs10210302 (ATG16L1), rs2066844, rs2066845, rs2066847 (NOD2), rs35873774 (XBP1), rs11175593 (LRRK2), rs11465804 (IL23R), rs2301436 (CCR6), rs744166 (STAT3) and rs4821544 (NCF4) SNP status were determined. RESULTS: No associations were found between genetic variants of the LRRK2, CCR6, IL23R and NCF4 genes and response to anti-TNFα. For NOD2 and XBP1 associations were found, however, these associations were not strong enough to survive multiple testing corrections. Strikingly, patients carrying the ATG16L1 T300A variant were more likely to be treated with adalimumab, even after correction for disease phenotype, disease behavior and age (p = 0.004, OR 2.8, CI 1.6-5.0). CONCLUSIONS: Genetic polymorphisms in the known IBD-associated gene ATG16L1 correlate with requirement of treatment, suggesting a different IBD disease phenotype in these patients. Further investigation will need to elucidate the implications of these findings and identify the underlying disease characteristics.


Subject(s)
Adalimumab/therapeutic use , Autophagy-Related Proteins/genetics , Genetic Association Studies , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/genetics , Polymorphism, Single Nucleotide/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Gene Frequency/genetics , Genetic Predisposition to Disease , Humans , Logistic Models , Male , Middle Aged , Young Adult
11.
Best Pract Res Clin Gastroenterol ; 31(6): 607-618, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29566903

ABSTRACT

Advances in research techniques have made it possible to map the microbial communities in the gastrointestinal (GI) tract, where the majority of bacteria in the human body reside. Disturbances in these communities are referred to as dysbiosis and have been associated with GI cancers. Although dysbiosis is observed in several GI malignancies, the specific role of these changes has not been understood to the extent of Helicobacter pylori (HP) in gastric cancer (GC). This review will address the bacterial communities along the GI tract, from the oral cavity to the anal canal, particularly focusing on bacterial dysbiosis and carcinogenesis. Just as non-HP bacteria in the stomach may interact with HP in gastric carcinogenesis, the same may hold true for other GI tract malignancies, where an interplay between microbes in carcinogenesis seems conceivable, especially in colorectal cancer (CRC). In the last part of this review we will discuss the potential mechanisms of bacterial dysbiosis in GI carcinogenesis.


Subject(s)
Carcinogenesis/genetics , Cell Transformation, Neoplastic/genetics , Gastrointestinal Microbiome/genetics , Gastrointestinal Neoplasms/genetics , Gastrointestinal Neoplasms/microbiology , Gastrointestinal Neoplasms/pathology , Humans
12.
Mucosal Immunol ; 10(2): 352-360, 2017 03.
Article in English | MEDLINE | ID: mdl-27435106

ABSTRACT

Thiopurines are commonly used drugs in the therapy of Crohn's disease, but unfortunately only show a 30% response rate. The biological basis for the thiopurine response is unclear, thus hampering patient selection prior to treatment. A genetic risk factor associated specifically with Crohn's disease is a variant in ATG16L1 that reduces autophagy. We have previously shown that autophagy is involved in dendritic cell (DC)-T-cell interactions and cytoskeletal regulation. Here we further investigated the role of autophagy in DC cytoskeletal modulation and cellular trafficking. Autophagy-deficient DC displayed loss of filopodia, altered podosome distribution, and increased membrane ruffling, all consistent with increased cellular adhesion. Consequently, autophagy-deficient DC showed reduced migration. The cytoskeletal aberrations were mediated through hyperactivation of Rac1, a known thiopurine target. Indeed thiopurines restored the migratory defects in autophagy-deficient DC. Clinically, the ATG16L1 risk variant associated with increased response to thiopurine treatment in patients with Crohn's disease but not ulcerative colitis. These results suggest that the association between ATG16L1 and Crohn's disease is mediated at least in part through Rac1 hyperactivation and subsequent defective DC migration. As this phenotype can be corrected using thiopurines, ATG16L1 genotyping may be useful in the identification of patients that will benefit most from thiopurine treatment.


Subject(s)
Autophagy-Related Proteins/metabolism , Autophagy , Crohn Disease/immunology , Dendritic Cells/physiology , rac1 GTP-Binding Protein/metabolism , Alleles , Animals , Autophagy/genetics , Autophagy-Related Proteins/genetics , Cell Membrane Structures/pathology , Cell Movement , Cells, Cultured , Colitis, Ulcerative/drug therapy , Crohn Disease/drug therapy , Crohn Disease/genetics , Cytoskeleton/metabolism , Dendritic Cells/pathology , Female , Genetic Predisposition to Disease , Humans , Mercaptopurine/therapeutic use , Mice , Mice, Inbred C57BL , Mice, Knockout , Polymorphism, Genetic , RNA, Small Interfering/genetics , Risk
13.
Mol Ther Nucleic Acids ; 5: e350, 2016.
Article in English | MEDLINE | ID: mdl-28131248

ABSTRACT

A subset of pancreatic cystic neoplasms are regarded as precursor lesions of pancreatic cancer, but only a minority of all pancreatic cystic neoplasms will undergo malignant transformation. MicroRNAs are increasingly recognized as molecular targets in carcinogenesis. Previously, a 9-microRNA (miR) signature was suggested to discriminate between high risk and low risk pancreatic cystic neoplasm. In this study, we aimed to validate this 9-miR panel in a prospective cohort. Total miR was isolated from pancreatic cyst fluid and expression of miR18a, miR24, miR30a-3p, miR92a, miR99b, miR106b, miR142-3p, miR342-3p, and miR532-3p was analyzed by singleplex Taqman MicroRNA Assay. A total of 62 patient samples were analyzed. During follow-up, 24 (38.7%) patients underwent resection, of which 6 (9.7%) patients showed at least high grade dysplasia. A logistic regression model presented a "predicted risk" score which significantly differed between low and high risk cysts, either including all patients or only those with histological confirmation of diagnosis. Using a set cut-off of 50%, the sensitivity of the model for the total cohort was 10.0%, specificity 100.0%, positive predicted value 100.0%, negative predicted value 85.2%, and diagnostic accuracy of 85.5%. Thus, while observing a significant difference between low and high risk cysts, clinical implementation of this biomarker panel is as yet unlikely to be beneficial in the management of pancreatic cysts.

14.
J Viral Hepat ; 23(4): 294-304, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26620360

ABSTRACT

Hepatitis E virus (HEV) represents one of the foremost causes of acute hepatitis globally. Although there is no proven medication for hepatitis E, pegylated interferon-α (IFN-α) has been used as off-label drug for treating HEV. However, the efficacy and molecular mechanisms of how IFN signalling interacts with HEV remain undefined. As IFN-α has been approved for treating chronic hepatitis C (HCV) for decades and the role of interferon signalling has been well studied in HCV infection, this study aimed to comprehensively investigate virus-host interactions in HEV infection with focusing on the IFN signalling, in comparison with HCV infection. A comprehensive screen of human cytokines and chemokines revealed that IFN-α was the sole humoral factor inhibiting HEV replication. IFN-α treatment exerted a rapid and potent antiviral activity against HCV, whereas it had moderate and delayed anti-HEV effects in vitro and in patients. Surprisingly, blocking the basal IFN pathway by inhibiting JAK1 to phosphorylate STAT1 has resulted in drastic facilitation of HEV, but not HCV infection. Gene silencing of the key components of JAK-STAT cascade of the IFN signalling, including JAK1, STAT1 and interferon regulatory factor 9 (IRF9), stimulated HEV infection. In conclusion, compared to HCV, HEV is less sensitive to IFN treatment. In contrast, the basal IFN cascade could effectively restrict HEV infection. This bears significant implications in management of HEV patients and future therapeutic development.


Subject(s)
Hepatitis E virus/immunology , Hepatitis E/pathology , Hepatitis E/therapy , Host-Pathogen Interactions , Interferon-alpha/metabolism , Antiviral Agents/metabolism , Antiviral Agents/therapeutic use , Cell Line, Tumor , Hepatitis C, Chronic/pathology , Hepatitis C, Chronic/therapy , Hepatitis E virus/physiology , Hepatocytes/virology , Humans , Interferon-alpha/therapeutic use , Virus Replication
15.
Sci Rep ; 5: 17259, 2015 Nov 30.
Article in English | MEDLINE | ID: mdl-26616161

ABSTRACT

The affinity of zeolite nanoparticles (diameter of 8-12 nm) possessing high surface area and high pore volume towards human plasma proteins has been investigated. The protein composition (corona) of zeolite nanoparticles has been shown to be more dependent on the plasma protein concentrations and the type of zeolites than zeolite nanoparticles concentration. The number of proteins present in the corona of zeolite nanoparticles at 100% plasma (in vivo state) is less than with 10% plasma exposure. This could be due to a competition between the proteins to occupy the corona of the zeolite nanoparticles. Moreover, a high selective adsorption for apolipoprotein C-III (APOC-III) and fibrinogen on the zeolite nanoparticles at high plasma concentration (100%) was observed. While the zeolite nanoparticles exposed to low plasma concentration (10%) exhibited a high selective adsorption for immunoglobulin gamma (i.e. IGHG1, IGHG2 and IGHG4) proteins. The zeolite nanoparticles can potentially be used for selectively capture of APOC-III in order to reduce the activation of lipoprotein lipase inhibition during hypertriglyceridemia treatment. The zeolite nanoparticles can be adapted to hemophilic patients (hemophilia A (F-VIII deficient) and hemophilia B (F-IX deficient)) with a risk of bleeding, and thus might be potentially used in combination with the existing therapy.


Subject(s)
Blood Proteins , Nanoparticles , Zeolites , Adsorption , Apolipoprotein C-III/chemistry , Blood Coagulation , Blood Proteins/chemistry , Chromatography, Liquid , Fibrinogen/chemistry , Humans , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Nitrogen/chemistry , Protein Corona , Tandem Mass Spectrometry , Zeolites/chemistry
16.
Am J Transplant ; 15(3): 585-93, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25693470

ABSTRACT

Although rotavirus is usually recognized as the most common etiology of diarrhea in young children, it can in fact cause severe diseases in organ transplantation recipients irrespective of pediatric or adult patients. This comprehensive literature analysis revealed 200 cases of rotavirus infection with 8 related deaths in the setting of organ transplantation been recorded. Based on published cohort studies, an average incidence of 3% (187 infections out of 6176 organ recipients) was estimated. Rotavirus infection often causes severe gastroenteritis complications and occasionally contributes to acute cellular rejection in these patients. Immunosuppressive agents, universally used after organ transplantation to prevent organ rejection, conceivably play an important role in such a severe pathogenesis. Interestingly, rotavirus can in turn affect the absorption and metabolism of particular immunosuppressive medications via several distinct mechanisms. Even though rotaviral enteritis is self-limiting in general, infected transplantation patients are usually treated with intensive care, rehydration and replacement of nutrition, as well as applying preventive strategies. This article aims to properly assess the clinical impact of rotavirus infection in the setting of organ transplantation and to disseminate the interactions among the virus, host and immunosuppressive medications.


Subject(s)
Host-Pathogen Interactions , Immunosuppressive Agents/therapeutic use , Organ Transplantation , Rotavirus/pathogenicity , Graft Rejection/prevention & control , Humans
17.
Br J Cancer ; 112(1): 122-30, 2015 Jan 06.
Article in English | MEDLINE | ID: mdl-25393365

ABSTRACT

BACKGROUND: Constitutive Wnt activation is essential for colorectal cancer (CRC) initiation but also underlies the cancer stem cell phenotype, metastasis and chemosensitivity. Importantly Wnt activity is still modulated as evidenced by higher Wnt activity at the invasive front of clonal tumours termed the ß-catenin paradox. SMAD4 and p53 mutation status and the bone morphogenetic protein (BMP) pathway are known to affect Wnt activity. The combination of SMAD4 loss, p53 mutations and BMP signalling may integrate to influence Wnt signalling and explain the ß-catenin paradox. METHODS: We analysed the expression patterns of SMAD4, p53 and ß-catenin at the invasive front of CRCs using immunohistochemistry. We activated BMP signalling in CRC cells in vitro and measured BMP/Wnt activity using luciferase reporters. MTT assays were performed to study the effect of BMP signalling on CRC chemosensitivity. RESULTS: Eighty-four percent of CRCs with high nuclear ß-catenin staining are SMAD4 negative and/or p53 aberrant. BMP signalling inhibits Wnt signalling in CRC only when p53 and SMAD4 are unaffected. In the absence of SMAD4, BMP signalling activates Wnt signalling. When p53 is lost or mutated, BMP signalling no longer influences Wnt signalling. The cytotoxic effects of 5-FU are influenced in a similar manner. CONCLUSIONS: The BMP signalling pathway differentially modulates Wnt signalling dependent on the SMAD4 and p53 status. The use of BMPs in cancer therapy, as has been proposed by previous studies, should be targeted to individual cancers based on the mutational status of p53 and SMAD4.


Subject(s)
Bone Morphogenetic Proteins/metabolism , Colorectal Neoplasms/metabolism , Smad4 Protein/metabolism , Tumor Suppressor Protein p53/metabolism , Wnt Signaling Pathway , Bone Morphogenetic Proteins/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , HCT116 Cells , HEK293 Cells , HT29 Cells , Humans , Signal Transduction , Transfection , Tumor Suppressor Protein p53/genetics , beta Catenin/genetics , beta Catenin/metabolism
18.
Oncogene ; 34(39): 5055-68, 2015 Sep 24.
Article in English | MEDLINE | ID: mdl-25531314

ABSTRACT

Further understanding of the molecular biology and pathogenesis of hepatocellular carcinoma (HCC) is crucial for future therapeutic development. SMAD4, recognized as an important tumor suppressor, is a central mediator of transforming growth factor beta (TGFB) and bone morphogenetic protein (BMP) signaling. This study investigated the role of SMAD4 in HCC. Nuclear localization of SMAD4 was observed in a cohort of 140 HCC patients using tissue microarray. HCC cell lines were used for functional assay in vitro and in immune-deficient mice. Nuclear SMAD4 levels were significantly increased in patient HCC tumors as compared with adjacent tissues. Knockdown of SMAD4 significantly reduced the efficiency of colony formation and migratory capacity of HCC cells in vitro and was incompatible with HCC tumor initiation and growth in mice. Knockdown of SMAD4 partially conferred resistance to the anti-growth effects of BMP ligand in HCC cells. Importantly, simultaneous elevation of SMAD4 and phosphorylated SMAD2/3 is significantly associated with poor patient outcome after surgery. Although high levels of SMAD4 can also mediate an antitumor function by coupling with phosphorylated SMAD1/5/8, this signaling, however, is absent in majority of our HCC patients. In conclusion, this study revealed a highly non-canonical tumor-promoting function of SMAD4 in HCC. The drastic elevation of nuclear SMAD4 in sub-population of HCC tumors highlights its potential as an outcome predictor for patient stratification and a target for personalized therapeutic development.


Subject(s)
Carcinogenesis , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Smad4 Protein/physiology , Animals , Cell Line, Tumor , Gene Knockdown Techniques , Gene Silencing , Humans , Mice , Phosphorylation , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Smad4 Protein/genetics
19.
Aliment Pharmacol Ther ; 40(10): 1202-8, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25263077

ABSTRACT

BACKGROUND: Adalimumab is an effective therapy for Crohn's disease patients. However, there is limited knowledge on the pharmacokinetic properties of adalilumab in patients with Crohn's disease. AIM: To assess the pharmacokinetic properties of adalilumab in a retrospective clinical cohort of patients with Crohn's disease, naïve to anti-tumour necrosis factor alpha therapy (anti-TNF). METHODS: In a single tertiary centre, a clinical retrospective cohort was formed out of 76 patients with Crohn's disease who started adalilumab treatment (160/80/40EOW) between July 2007 and September 2010. We serially evaluated adalilumab serum levels at week 0, 12 and 28. RESULTS: Patients were followed for a median time of 201 days (range 120-244) and received a median of 14 adalilumab injections (range 6-25). Adalilumab levels, although divergent between patients, were stable between week 12 and week 28. There was no correlation between adalilumab level and time since last administration (r = -0.061). In a multivariable regression analysis of patient factors influencing week 28 adalilumab levels, the regression model containing CRP at week 28 and BMI at baseline weakly but significantly predicted week 28 adalilumab levels (R(2) = 0.193, P = 0.004). Concomitant use of immunosuppressives was not a significant predictor (P = 0.304). CONCLUSIONS: Intra-individual adalilumab levels seem very stable during the first 28 weeks of treatment, whereas inter-individual levels vary. Adalilumab levels appear stable over a 2-week period, as the time since last adalilumab administration did not affect the adalilumab level. CRP and BMI weakly predict week 28 adalilumab levels, whereas the use of immunosuppressives does not.


Subject(s)
Anti-Inflammatory Agents/pharmacokinetics , Antibodies, Monoclonal, Humanized/pharmacokinetics , Crohn Disease/blood , Adalimumab , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Inflammatory Agents/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Body Mass Index , C-Reactive Protein/analysis , Crohn Disease/drug therapy , Drug Therapy, Combination , Female , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Retrospective Studies , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Young Adult
20.
Thromb Haemost ; 111(3): 518-30, 2014 Mar 03.
Article in English | MEDLINE | ID: mdl-24500811

ABSTRACT

Apart from transporting lipids through the body, the human plasma lipoproteins very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL) are also thought to serve as a modality for intra-organismal protein transfer, shipping proteins with important roles in inflammation and thrombosis from the site of synthesis to effector locations. To better understand the role of VLDL and LDL in the transport of proteins, we applied a combination of LTQ ORBITRAP-XL (nLC-MS/MS) with both in-SDS-PAGE gel and in-solution tryptic digestion of pure and defined VLDL and LDL fractions. We identified the presence of 95 VLDL- and 51 LDL-associated proteins including all known apolipoproteins and lipid transport proteins, and intriguingly a set of coagulation proteins, complement system and anti- microbial proteins. Prothrombin, protein S, fibrinogen γ, PLTP, CETP, CD14 and LBP were present on VLDL but not on LDL. Prenylcysteine oxidase 1, dermcidin, cathelicidin antimicrobial peptide, TFPI-1 and fibrinogen α chain were associated with both VLDL and LDL. Apo A-V is only present on VLDL and not on LDL. Collectively, this study provides a wealth of knowledge on the protein constituents of the human plasma lipoprotein system and strongly supports the notion that protein shuttling through this system is involved in the regulation of biological processes. Human diseases related to proteins carried by VLDL and LDL can be divided in three major categories: 1 - dyslipidaemia, 2 - atherosclerosis and vascular disease, and 3 - coagulation disorders.


Subject(s)
Atherosclerosis/blood , Blood Coagulation Disorders/blood , Dyslipidemias/blood , Lipoproteins, LDL/metabolism , Lipoproteins, VLDL/metabolism , Plasma/metabolism , Proteome/metabolism , Antimicrobial Cationic Peptides/metabolism , Apolipoprotein A-V , Apolipoproteins A/metabolism , Blood Coagulation , Carbon-Sulfur Lyases/metabolism , Cathepsin D/metabolism , Cholesterol Ester Transfer Proteins/metabolism , Computational Biology , Humans , Lipid Metabolism , Lipopolysaccharide Receptors/metabolism , Lipoproteins/metabolism , Mass Spectrometry , Muramidase/metabolism , Phosphatidylcholine-Sterol O-Acyltransferase/metabolism , Phospholipid Transfer Proteins/metabolism , Protein S/metabolism , Prothrombin/metabolism
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