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1.
Microb Pathog ; 187: 106487, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158143

RESUMO

Escherichia coli LF82 (LF82) is associated with Crohn's disease. The simplicity and genetic maneuverability of honeybees' gut microbiota make them suitable for studying host-microbe interactions. To understand the interaction between LF82 and host gut, LF82 was used to infect germ-free honeybees (Apis mellifera) orally. We found that LF82 successfully colonized the gut and shortened the lifespan of germ-free bees. LF82 altered the gut structure and significantly increased gut permeability. RT-qPCR showed that LF82 infection activated anti-infective immune pathways and upregulated the mRNAs levels of antimicrobial peptides in the gut of germ-free bees. The gut transcriptome showed that LF82 significantly upregulated genes involved in Notch signaling, adhesion junctions, and Toll and Imd signaling pathways and downregulated genes involved in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, protein digestion and absorption, and tyrosine metabolism. In conclusion, the human-derived enteropathogenic bacterium LF82 can successfully colonize the gut of germ-free honeybees and cause enteritis-like changes, which provides an ideal model organism for revealing the pathogenesis of bacterial-associated diseases.


Assuntos
Doença de Crohn , Infecções por Escherichia coli , Abelhas , Humanos , Animais , Escherichia coli/genética , Mucosa Intestinal/microbiologia , Aderência Bacteriana , Infecções por Escherichia coli/microbiologia
2.
Front Microbiol ; 14: 1278162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075901

RESUMO

Autism spectrum disorder (ASD) is a set of neurodevelopmental disorders, with an increasing incidence. Gastrointestinal symptoms are common comorbidities of ASD. The gut microbiota composition of children with autism is distinct from that of typical developmental (TD) children, suggesting that the gut microbiota probably influences on hosts via the microbiota-gut-brain axis. However, the relationship between intestinal dysbiosis and host brain function remains unclear. In this study, we creatively developed a honeybee model and investigated the potential effects of fecal microbiota on hosts. Fecal microbiota from children with autism and TD children were transplanted into microbiota-free honeybees (Apis mellifera), resulting in induced ASD-fecal microbiota transplantation (FMT) honeybees (A-BEE group) and TD-FMT honeybees (T-BEE group), respectively. We found that cognitive abilities of honeybees in the A-BEE group were significantly impaired in olfactory proboscis extension response conditioning. Metagenomics was used to evaluate fecal microbiota colonization, revealing several differential species responsible for altered tryptophan metabolism and taurine metabolism within the bee gut, including Bacteroides dorei, Bacteroides fragilis, Lactobacillus gasseri, and Lactobacillus paragasseri. Furthermore, fecal microbiota from children with autism downregulated brain genes involved in neural signaling and synaptic transmission within honeybees. Notably, differentially spliced genes observed within brains of honeybees from the A-BEE group largely overlapped with those identified in human diagnosed with autism via SFARI and SPARK gene sets. These differentially spliced genes were also enriched within pathways related to neural synaptic transmission. Our findings provide novel insights into the pivotal role of the human gut microbiota, which may contribute to neurological processes in honeybees. Additionally, we present a few research sources on gut-brain connections in ASD.

3.
BMJ Open ; 13(10): e073335, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798018

RESUMO

OBJECTIVE: This study aimed to construct prognostic models to predict the overall survival (OS) and cancer-specific survival (CSS) of patients with primary gastrointestinal melanoma (PGIM). DESIGN: An observational and retrospective study. SETTING: Data were obtained from the Surveillance, Epidemiology and End Results (SEER) programme database, encompassing a broad geographical and demographic spectrum of patients across the USA. PARTICIPANTS: A total of 991 patients diagnosed with PGIM were included in this study. METHODS: A total of 991 patients with PGIM were selected from the SEER database. They were further divided into a training cohort and a validation cohort. Independent prognostic factors were identified by Cox regression analysis. Two prognostic models were constructed based on the results of multivariable Cox regression analysis. The concordance index (C-index) and area under the time-dependent receiver operating characteristic curve (time-dependent AUC) were used to evaluate the discriminative ability. Calibration curves were plotted to evaluate the agreement between the probability as predicted by the models and the actual probability. Risk stratification was developed given the model. RESULTS: By the multivariable Cox regression analysis, we identified four independent risk factors (age, stage, lymph node density and surgery) for OS, and three independent risk factors (stage, lymph node density and surgery) for CSS, which were used to construct prognostic models. C-index, time-dependent AUC, calibration curves and Kaplan-Meier curves of risk stratification indicated that these two models had good discriminative ability, predictive ability as well as clinical value. CONCLUSIONS: The prognostic models of OS and CSS had satisfactory accuracy and were of clinical value in evaluating the prognosis of patients with PGIM.


Assuntos
Neoplasias Gastrointestinais , Melanoma , Humanos , Prognóstico , Estudos Retrospectivos , Linfonodos , Fatores de Risco , Nomogramas
4.
Gut Microbes ; 15(1): 2236364, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37482657

RESUMO

Colorectal cancer (CRC) is the third most common malignant tumor worldwide. The incidence and mortality rates of CRC have been increasing in China, possibly due to economic development, lifestyle, and dietary changes. Evidence suggests that gut microbiota plays an essential role in the tumorigenesis of CRC. Gut dysbiosis, specific pathogenic microbes, metabolites, virulence factors, and microbial carcinogenic mechanisms contribute to the initiation and progression of CRC. Gut microbiota biomarkers have potential translational applications in CRC screening and early diagnosis. Gut microbiota-related interventions could improve anti-tumor therapy's efficacy and severe intestinal toxic effects. Chinese researchers have made many achievements in the relationship between gut microbiota and CRC, although some challenges remain. This review summarizes the current evidence from China on the role of gut microbiota in CRC, mainly including the gut microbiota characteristics, especially Fusobacterium nucleatum and Parvimonas micra, which have been identified to be enriched in CRC patients; microbial pathogens such as F. nucleatum and enterotoxigenic Bacteroides fragilis, and P. micra, which Chinese scientists have extensively studied; diagnostic biomarkers especially F. nucleatum; therapeutic effects, including microecological agents represented by certain Lactobacillus strains, fecal microbiota transplantation, and traditional Chinese medicines such as Berberine and Curcumin. More efforts should be focused on exploring the underlying mechanisms of microbial pathogenesis of CRC and providing novel gut microbiota-related therapeutic and preventive strategies.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Neoplasias Colorretais/diagnóstico , Carcinogênese , China , Biomarcadores
5.
Front Immunol ; 14: 1093233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911747

RESUMO

Ankylosing spondylitis (AS) is the prototype of a group of systemic inflammatory diseases referred to as spondyloarthritis. Comorbid inflammatory bowel disease and changed gut microbiota in AS have attracted attention to the influence of gut-joint axis and encouraged treating AS by targeting gut microbiota. Here we first reported a patient with refractory AS and comorbid ulcerative colitis (UC) who underwent three fecal microbiota transplantations (FMTs). Inadequate response to conventional treatments including tumor necrosis factor inhibitors impelled FMT as alternative therapy. Notable improvements in AS and UC accompanied with changed fecal microbiota were recorded at 1 week post-FMT1. Further recovery was found after the other two FMTs, and a roughly stable status was maintained in the follow-up period. More studies are needed to validate the effectiveness of FMT in AS and its mechanisms.


Assuntos
Colite Ulcerativa , Microbioma Gastrointestinal , Microbiota , Espondilite Anquilosante , Humanos , Transplante de Microbiota Fecal , Fezes , Colite Ulcerativa/patologia
6.
Mod Rheumatol ; 33(4): 823-829, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35727178

RESUMO

OBJECTIVES: To determine the frequency of symptoms meeting Rome IV functional bowel disorder (FBD) in patients with ankylosing spondylitis (AS), investigate factors associated with FBD symptoms, and assess whether having FBD symptoms might influence AS disease activity. METHODS: In this cross-sectional study, we enrolled 153 AS patients without known colonic ulcers and 56 sex- and age-matched controls to evaluate FBD (or its subtypes) symptoms. Disease characteristics were also evaluated in the AS group. RESULTS: Sixty (39.2%) of 153 AS patients had FBD symptoms, which were more prevalent than controls (23.2%). Besides, symptoms compatible with irritable bowel syndrome (IBS) and chronic diarrhoea were detected in 18 and 43 AS patients, respectively. For the AS group, multivariable logistic regression analyses showed that symptoms of FBD, IBS, and chronic diarrhoea were negatively associated with using non-steroidal anti-inflammatory drugs and positively associated with comorbid fibromyalgia, respectively. In exploration about the effects of FBD (or its subtypes) symptoms on AS disease activity by multivariable linear regression analyses, FBD symptoms and chronic diarrhoea had universal positive associations with assessments of AS disease characteristics, respectively. CONCLUSIONS: Patients with AS had frequent symptoms compatible with FBD, IBS, and chronic diarrhoea, proportions of which were lower in those with non-steroidal anti-inflammatory drug use. The improvement of FBD symptoms and chronic diarrhoea might be conducive to the disease status of AS patients.


Assuntos
Gastroenteropatias , Síndrome do Intestino Irritável , Espondilite Anquilosante , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/diagnóstico , Estudos Transversais , Cidade de Roma , Espondilite Anquilosante/complicações , Gastroenteropatias/diagnóstico , Diarreia/complicações , Anti-Inflamatórios não Esteroides/uso terapêutico , Inquéritos e Questionários
7.
Comput Methods Programs Biomed ; 228: 107240, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36417837

RESUMO

OBJECTIVE: Highlights always occur in endoscopic images due to their special imaging environment. It not only increases the difficulty of observation and diagnosis from surgeons, but also influences the performance of Mixed/Augmented Reality techniques in surgery navigation. METHODS: In this paper, we propose a novel accelerated adaptive non-convex robust principal component analysis method (AANC-RPCA) to remove highlights in endoscopic images. We first detect absolute highlight pixels of the enhanced endoscopic images with adaptive threshold segmentation. The quasi-convex function is proposed to approximate a new non-convex objective function. With detected highlight pixels and quasi-convex function, it introduces gradient to shrink sparse matrix and obtains a faster speed of convergence. Then we divide the image into multiple blocks and perform the parallel computation to enhance the efficiency. Finally, we design a weighted template that decays outward with dilation and linear filtering to reconstruct the endoscopic images. Our approach is almost independent of hyper-parameters and can achieve adaptive decomposition. RESULTS: It has been verified on multiple types of endoscopic images through experiments and clinical blind tests. The results demonstrate that our method can obtain the best performance for the recovered images with more details in a shorter time (about 3-5 times). CONCLUSION: Coupled with the user study, both the quantitative and qualitative results indicate that our approach has the potential to be highly useful in endoscopy images. Compared with the existing highlight removal approaches, our method obtains the SOTA results and has the potential to be applied in the various medical processing processes.

8.
BMC Pulm Med ; 22(1): 136, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395795

RESUMO

BACKGROUND: Bronchoscopy is critical in the treatment of patients with coronavirus disease (COVID-19), and its use is associated with the challenges of stringent sterilization and virus transmission risk. We developed a disposable and portable bronchoscope (YunSendo-R) and compared its safety and function with those of current reusable and single-use bronchoscopes using an animal model. METHODS: We compared the YunSendo-R system with a commercially available reusable bronchoscope (Olympus, BF-H290) and single-use bronchoscope (Ambu, Ambu® aScope3™). Eight physicians used the three types of bronchoscopes to operate on Guangxi Bama mini pigs. Each operator performed bronchoscopy and completed a 10-point Likert scale questionnaire for evaluating visual ability and manoeuvrability. Operation time and scores were collected. RESULTS: Operation time had no significant differences among the three bronchoscopes. In visual ability, the YunSendo-R bronchoscope showed superior performance to the Ambu bronchoscope in image clarity, colour contrast, and illumination (P < 0.05) and no significant difference in performance compared with the Olympus bronchoscope (P > 0.05). The YunSendo-R bronchoscope had similar manoeuvrability to the Olympus bronchoscope and better scope tip flexibility than the Ambu bronchoscope (P > 0.05). No relevant complications were reported. CONCLUSION: We have developed a new bronchoscopy system with the advantages of disposability and portability, which was effective and safe in an animal model. It has better visual ability than the Ambu bronchoscope and similar visual ability and manoeuvrability to the Olympus bronchoscope. The YunSendo-R bronchoscope is a promising device for clinical practice, especially in reusable-endoscope-transmitted infectious diseases such as COVID-19.


Assuntos
Broncoscopia , COVID-19 , Animais , Broncoscópios , Broncoscopia/métodos , China , Humanos , Suínos , Porco Miniatura
9.
Comput Med Imaging Graph ; 94: 102007, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34741848

RESUMO

Despite the rapid technical advancement of augmented reality (AR) and mixed reality (MR) in minimally invasive surgery (MIS) in recent years, monocular-based 2D/3D reconstruction still remains technically challenging in AR/MR guided surgery navigation nowadays. In principle, soft tissue surface is smooth and watery with sparse texture, specular reflection, and frequent deformation. As a result, we frequently obtain only sparse feature points that give rise to incorrect matching results with conventional image processing methods. To ameliorate, in this paper we enunciate an accurate and robust description and matching method for dense feature points in endoscopic videos. Our new method first extracts contours of the low-rank image sequences based on the adaptive robust principal component analysis (RPCA) decomposition. Then we propose a multi-scale dense geometric feature description approach, which simultaneously extracts dense feature descriptors of the contours in the original Euclidean coordinate space, the accompanying 3D color coordinate space, and the derived curvature-gradient coordinate space. Finally, we devise a new algorithm for both global and local point-wise matching based on feature fusion. For global matching, we employ the fast Fourier transform (FFT) to reduce the dimension of the dense feature descriptors. For local feature point matching, in order to enhance the robustness and accuracy of the matching, we cluster multiple contour points to form "super-point" based on dense feature descriptors and their spatio-temporal continuity. The comprehensive experimental results confirm that our novel approach can overcome the highlight influence, and robustly describe contours from image sequences of soft tissue surfaces. Compared with the state-of-the-art feature point description and matching methods, our analysis framework shows the key advantages of both robustness and accuracy in dense point-wise matching, even when the severe soft tissue deformation occurs. Our new approach is expected to have high potential in 2D/3D reconstruction in endoscopy.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Endoscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Análise de Componente Principal
10.
Front Physiol ; 12: 704313, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262484

RESUMO

BACKGROUND AND AIMS: Biliary atresia (BA) is an idiopathic neonatal cholestasis and is the most common indication in pediatric liver transplantation (LT). Previous studies have suggested that the gut microbiota (GM) in BA is disordered. However, the effect of LT on gut dysbiosis in patients with BA has not yet been elucidated. METHODS: Patients with BA (n = 16) and healthy controls (n = 10) were recruited. In the early life of children with BA, Kasai surgery is a typical procedure for restoring bile flow. According to whether BA patients had previously undergone Kasai surgery, we divided the post-LT patients into the with-Kasai group (n = 8) and non-Kasai group (n = 8). Fecal samples were collected in both the BA and the control group; among BA patients, samples were obtained again 6 months after LT. A total of 40 fecal samples were collected, of which 16 were pre-LT, 14 were post-LT (8 were with-Kasai, 6 were non-Kasai), and 10 were from the control group. Metagenomic sequencing was performed to evaluate the GM. RESULTS: The Kruskal-Wallis test showed a statistically significant difference in the number of genes between the pre-LT and the control group, the pre-LT and the post-LT group (P < 0.05), but no statistical difference between the post-LT and the control group. Principal coordinate analysis also showed that the microbiome structure was similar between the post-LT and control group (P > 0.05). Analysis of the GM composition showed a significant decrease in Serratia, Enterobacter, Morganella, Skunalikevirus, and Phifllikevirus while short chain fatty acid (SCFA)-producing bacteria such as Roseburia, Blautia, Clostridium, Akkermansia, and Ruminococcus were increased after LT (linear discriminant analysis > 2, P < 0.05). However, they still did not reach the normal control level. Concerning functional profiles, lipopolysaccharide metabolism, multidrug resistance, polyamine biosynthesis, GABA biosynthesis, and EHEC/EPEC pathogenicity signature were more enriched in the post-LT group compared with the control group. Prior Kasai surgery had a specific influence on the postoperative GM. CONCLUSION: LT partly improved the GM in patients with BA, which provided new insight into understanding the role of LT in BA.

11.
Microb Pathog ; 157: 104964, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34022363

RESUMO

OBJECT: Fusobacterium nucleatum (F.nucleatum), a gram-negative, obligately anaerobe of oral commensal,has been regarded as culprit of periodontal diseases previously and is being unveiled as possible pathogen of gastrointestinal disorders. The key virulence factor of F.nucleatum is FadA adhesin for binding and invading of the host's epithelial cells. Here, we detected fecal F.nucleatum and virulence gene fadA in patients with ulcerative colitis(UC) and evaluated the clinical relevance with UC. METHODS AND SUBJECTS: A total of 310 subjects were enrolled including 100 patients with UC, 70 healthy controls (HC), 70 patients with irritable bowel syndrome subtype diarrhea(IBS-D), and 70 colorectal cancer patients(CRC). Stool samples of UC patients compared with healthy controls as well as IBS-D and CRC patients were collected for Polymerase Chain Reaction(PCR) detection of F.nucleatum (based on 16s rRNA) and virulence gene fadA. RESULTS: The detection rate of 16s rRNA based PCR for F.nucleatum of UC patients(39/100, 39.00%) and CRC(26/70, 37.14%) patients are significantly higher than HC (12/70, 17.14%, P < 0.01) and IBS-D patients (14/70, 20.00%, P < 0.01). Moreover, 19 samples were detected fadA positive from 39 F.nucleatum positive samples of UC patients (19/39, 48.72%), which is significantly higher than HC(2/12, 16.66%, P < 0.05). There were 3 samples detected fadA positive from 14 F.nucleatum positive samples of IBS-D patients(3/14, 21.43%) and 13 out of 26(50.00%) of CRC patients, which were both no significant differences compared with UC patients(21.4% vs 48.72%, P > 0.05; 50.00% vs 48.72%, P > 0.05). For both F.nucleatum and fadA gene positive patients, there were no statistical significances between erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), white blood cells(WBC), and hemoglobin compared with negative patients(defined by either F.nucleatum or fadA negative, or both negative). However, it is worth noting that detection rate of F.nucleatum with virulence gene fadA in patients of severe ulcerative colitis was significantly higher than patients with mild and moderate colitis(28.89% vs 10.91%, P < 0.05). In addition, the fecal F.nucleatum and fadA gene positive patients were more likely to have pancolitis other than left-sided colitis(pancolitis/left-sided colitis: 26.92% vs 10.42%, P < 0.05). CONCLUSIONS: The presence of F.nucleatum and fadA gene increased in UC patients, especially in patients with severe colitis and pancolitis. Strains of F.nucleatum harbored virulence gene fadA are suggested to play a role in the pathogenesis of UC.


Assuntos
Colite Ulcerativa , Fusobacterium nucleatum , Adesinas Bacterianas , Fusobacterium nucleatum/genética , Humanos , RNA Ribossômico 16S/genética , Virulência
12.
J Transl Med ; 19(1): 215, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006295

RESUMO

BACKGROUND: The fecal microbiota in pancreatic ductal adenocarcinoma (PDAC) and in autoimmune pancreatitis (AIP) patients remains largely unknown. We aimed to characterize the fecal microbiota in patients with PDAC and AIP, and explore the possibility of fecal microbial biomarkers for distinguishing PDAC and AIP. METHODS: 32 patients with PDAC, 32 patients with AIP and 32 age- and sex-matched healthy controls (HC) were recruited and the fecal microbiotas were analyzed through high-throughput metagenomic sequencing. Alterations of fecal short-chain fatty acids were measured using gas chromatographic method. RESULTS: Principal coordinate analysis (PCoA) revealed that microbial compositions differed significantly between PDAC and HC samples; whereas, AIP and HC individuals tended to cluster together. Significant reduction of phylum Firmicutes (especially butyrate-producing bacteria, including Eubacterium rectale, Faecalibacterium prausnitzii and Roseburia intestinalis) and significant increase of phylum Proteobacteria (especially Gammaproteobacteria) were observed only among PDAC samples. At species level, when compared with HC samples, we revealed 24 and 12 differently enriched bacteria in PDAC and AIP, respectively. Functional analysis showed a depletion of short-chain fatty acids synthesis associated KO modules (e.g. Wood-Ljungdahl pathway) and an increase of KO modules associated with bacterial virulence (e.g. type II general secretion pathway). Consistent with the downregulation of butyrate-producing bacteria, gas chromatographic analysis showed fecal butyrate content was significantly decreased in PDAC group. Eubacterium rectale, Eubacterium ventrisum and Odoribacter splanchnicus were among the most important biomarkers in distinguishing PDAC from HC and from AIP individuals. Receiver Operating Characteristic analysis showed areas under the curve of 90.74% (95% confidence interval [CI] 86.47-100%), 88.89% (95% CI 73.49-100%), and 76.54% (95% CI 52.5-100%) for PDAC/HC, PDAC/AIP and AIP/HC, respectively. CONCLUSIONS: In conclusion, alterations in fecal microbiota and butyrate of patients with PDAC suggest an underlying role of gut microbiota for the pathogenesis of PDAC. Fecal microbial and butyrate as potential biomarkers may facilitate to distinguish patients with PDAC from patients with AIP and HCs which worth further validation.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Neoplasias Pancreáticas , Doenças Autoimunes/diagnóstico , Bacteroidetes , Clostridiales , Diagnóstico Diferencial , Fezes , Humanos , Neoplasias Pancreáticas/diagnóstico
13.
Exp Ther Med ; 21(4): 372, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33732345

RESUMO

DEC1 has been reported to regulate the expression of multiple target genes, participate in cell differentiation, apoptosis, aging and the development and progression of numerous tumors, but the detailed effects and possible mechanisms of DEC1 in ovarian cancer (OC) remain unknown. The present study aimed to investigate the expression and mechanism of function of DEC1 in OC. The present results demonstrated that DEC1 was highly expressed in OC tissues and cell lines using reverse transcription-quantitative PCR, western blotting and immunohistochemistry, and high expression of DEC1 was negatively associated with the prognosis of patients with OC. In addition, knockdown of DEC1 significantly inhibited proliferation in SKOV3 and OVCAR3 cells compared with control. DEC1 knockdown also induced apoptosis and increased the expression of apoptosis-related proteins in OC cells. The results suggested that knockdown of DEC1 inhibited OC cell migration and invasion via regulation of epithelial-mesenchymal transition-related protein. It was also found that DEC1 knockdown significantly inhibited the Wnt/ß-catenin pathway. Collectively, the current results indicated that knockdown of DEC1 inhibited proliferation, migration and invasion, and induced apoptosis in OC cells via modulating the Wnt/ß-catenin signaling pathway. Thus, DEC1 may participate in malignant progression of OC, and may be a target for treatment and diagnosis of OC.

14.
Front Cell Infect Microbiol ; 11: 640309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777850

RESUMO

To characterize the salivary microbiota in patients at different progressive histological stages of gastric carcinogenesis and identify microbial markers for detecting gastric cancer, two hundred and ninety-three patients were grouped into superficial gastritis (SG; n = 101), atrophic gastritis (AG; n = 93), and gastric cancer (GC; n = 99) according to their histology. 16S rRNA gene sequencing was used to access the salivary microbiota profile. A random forest model was constructed to classify gastric histological types based on the salivary microbiota compositions. A distinct salivary microbiota was observed in patients with GC when comparing with SG and AG, which was featured by an enrichment of putative proinflammatory taxa including Corynebacterium and Streptococcus. Among the significantly decreased oral bacteria in GC patients including Haemophilus, Neisseria, Parvimonas, Peptostreptococcus, Porphyromonas, and Prevotella, Haemophilus, and Neisseria are known to reduce nitrite, which may consequently result in an accumulation of carcinogenic N-nitroso compounds. We found that GC can be distinguished accurately from patients with AG and SG (AUC = 0.91) by the random forest model based on the salivary microbiota profiles, and taxa belonging to unclassified Streptophyta and Streptococcus have potential as diagnostic biomarkers for GC. Remarkable changes in the salivary microbiota functions were also detected across three histological types, and the upregulation in the isoleucine and valine is in line with a higher level of these amino acids in the gastric tumor tissues that reported by other independent studies. Conclusively, bacteria in the oral cavity may contribute gastric cancer and become new diagnostic biomarkers for GC, but further evaluation against independent clinical cohorts is required. The potential mechanisms of salivary microbiota in participating the pathogenesis of GC may include an accumulation of proinflammatory bacteria and a decline in those reducing carcinogenic N-nitroso compounds.


Assuntos
Gastrite , Microbiota , Neoplasias Gástricas , Humanos , RNA Ribossômico 16S
18.
Exp Cell Res ; 396(1): 112242, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32866497

RESUMO

FAM122A is a housekeeping gene and highly conserved in mammals. More recently, we have demonstrated that FAM122A is essential for maintaining the growth of hepatocellular carcinoma cells, in which we unexpectedly found that FAM122A deletion increases γH2AX protein level, suggesting that FAM122A may participate in the regulation of DNA homeostasis or stability. In this study, we continued to investigate the potential role of FAM122A in DNA damage and/or repair. We found that CRISPR/Cas9-mediated FAM122A deletion enhances endogenous DNA damages in cancer cells but not in normal cells, demonstrating a significant increase in γH2AX protein and foci formation of γH2AX and 53BP1, as well as DNA breaks by comet assay. Further, we found that FAM122A deletion greatly increases TOP2α protein level, and significantly and specifically enhances TOP2 poisons (etoposide and doxorubicin)-induced DNA damage effects in cancer cells. Moreover, FAM122A is found to be interacted with TOP2α, instead of TOP2ß. However, FAM122A knockout doesn't affect the intracellular ROS levels and the process of DNA repair after removal of etoposide with short-term stimulation, suggesting that FAM122A deletion-enhanced DNA damage does not result from endogenous overproduction of ROS and/or impairment of DNA repair ability. Collectively, our study provides the first demonstration that FAM122A is critical for maintaining DNA stability probably by modulating TOP2α protein, and FAM122A deletion combined with TOP2-targeted drugs may represent a potential novel chemotherapeutic strategy for cancer patients.


Assuntos
DNA Topoisomerases Tipo II/genética , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosfoproteínas/genética , Antineoplásicos/farmacologia , Apoptose/genética , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , DNA de Neoplasias/metabolismo , Doxorrubicina/farmacologia , Etoposídeo/farmacologia , Fibroblastos , Deleção de Genes , Células HEK293 , Células HeLa , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Fosfoproteínas/deficiência , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Inibidores da Topoisomerase II/farmacologia , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
19.
Stem Cell Reports ; 15(3): 721-734, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32763160

RESUMO

FAM122A is a highly conserved housekeeping gene, but its physiological and pathophysiological roles remain greatly elusive. Based on the fact that FAM122A is highly expressed in human CD71+ early erythroid cells, herein we report that FAM122A is downregulated during erythroid differentiation, while its overexpression significantly inhibits erythrocytic differentiation in primary human hematopoietic progenitor cells and erythroleukemia cells. Mechanistically, FAM122A directly interacts with the C-terminal zinc finger domain of GATA1, a critical transcriptional factor for erythropoiesis, and reduces GATA1 chromatin occupancy on the promoters of its target genes, thus resulting in the decrease of GATA1 transcriptional activity. The public datasets show that FAM122A is abnormally upregulated in patients with ß-thalassemia. Collectively, our results demonstrate that FAM122A plays an inhibitory role in the regulation of erythroid differentiation, and it would be a potentially therapeutic target for GATA1-related dyserythropoiesis or an important regulator for amplifying erythroid cells ex vivo.


Assuntos
Diferenciação Celular , Células Eritroides/citologia , Células Eritroides/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Antígenos CD34/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , DNA/metabolismo , Regulação para Baixo/genética , Células Eritroides/efeitos dos fármacos , Eritropoetina/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Células K562 , Fosfoproteínas/química , Ligação Proteica/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Dedos de Zinco
20.
Front Microbiol ; 11: 997, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547510

RESUMO

The changes of gastric microbiome across stages of neoplastic progression remain poorly understood, especially for intraepithelial neoplasia (IN) which has been recognized as a phenotypic bridge between atrophic/intestinal metaplastic lesions and invasive cancer. The gastric microbiota was investigated in 30 healthy controls (HC), 21 non-atrophic chronic gastritis (CG), 27 gastric intestinal metaplasia (IM), 25 IN, and 29 gastric cancer (GC) patients by 16S rRNA gene profiling. The bacterial diversity, and abundances of phyla Armatimonadetes, Chloroflexi, Elusimicrobia, Nitrospirae, Planctomycetes, Verrucomicrobia, and WS3 reduced progressively from CG, through IM, IN to GC. Actinobacteria, Bacteriodes, Firmicutes, Fusobacteria, SR1, and TM7 were enriched in the IN and GC. At the community level, the proportions of Gram-positive and anaerobic bacteria increased in the IN and GC compared to other histological types, whereas the aerobic and facultatively anaerobic bacteria taxa were significantly reduced in GC. Remarkable changes in the gastric microbiota functions were detected after the formation of IN. The reduced nitrite-oxidizing phylum Nitrospirae together with a decreased nitrate/nitrite reductase functions indicated nitrate accumulation during neoplastic progression. We constructed a random forest model, which had a very high accuracy (AUC > 0.95) in predicating the histological types with as low as five gastric bacterial taxa. In summary, the changing patterns of the gastric microbiota composition and function are highly indicative of stages of neoplastic progression.

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