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World Journal of Gastroenterology Aug 2021Gut microbial dysbiosis contributes to the development and progression of colorectal cancer (CRC). Natural killer (NK) cells are involved in early defense mechanisms to...
BACKGROUND
Gut microbial dysbiosis contributes to the development and progression of colorectal cancer (CRC). Natural killer (NK) cells are involved in early defense mechanisms to kill infective pathogens and tumor cells by releasing chemokines and cytokines. To better understand the relationship between the gut microbiome and CRC, it was hypothesized here that a high abundance of () in the gastrointestinal tract could cause reduced NK cell activity.
AIM
To identify associations between gastrointestinal tract levels and NK cell activity.
METHODS
experiments were performed on NK cells treated with and to identify the effects of gut microbiome species on NK cells. Following 24 and 48 h of treatment, NK cell counts were measured. In parallel studies, C57BL/6 mice were given broad-spectrum antibiotics in their drinking water to reduce resident gut flora. After 3 wk, the mice received the various bacterial species or phosphate-buffered saline (PBS) oral gavage every 2 d for 6 wk. At the study end, blood samples were acquired to perform NK cell activity assessment and cytokine analysis. Intestinal tissues were collected and analyzed immunohistochemistry (IHC).
RESULTS
The data show that after 3 wk of broad-spectrum antibiotic treatment, levels of total bacteria and were markedly decreased in mice. Gavage of significantly decreased NK cell activity relative to the activities of cells from mice treated with antibiotics only and PBS. The administration of decreased the proportion of NK46 cells based on IHC staining and increased the production of interleukin-1β and tumor necrosis factor-α.
CONCLUSION
High levels of in the gastrointestinal tract reduced NK cell activity in mice, and the decrease in NK cell activity might be affected by increased pro-inflammatory cytokines after treatment
Topics: Animals; Firmicutes; Fusobacterium nucleatum; Gastrointestinal Tract; Killer Cells, Natural; Mice; Mice, Inbred C57BL; Peptostreptococcus
PubMed: 34447232
DOI: 10.3748/wjg.v27.i29.4879 -
Gut Pathogens Dec 2022Colorectal cancer (CRC) is a multifactorial disease with genetic and environmental factors. Regional differences in risk factors are an important reason for the...
BACKGROUND
Colorectal cancer (CRC) is a multifactorial disease with genetic and environmental factors. Regional differences in risk factors are an important reason for the different incidences of CRC in different regions.
OBJECTIVE
The goal was to clarify the intestinal microbial composition and structure of CRC patients in different regions and construct CRC risk prediction models based on regional differences.
METHODS
A metagenomic dataset of 601 samples from 6 countries in the GMrepo and NCBI databases was collected. All whole-genome sequencing (WGS) data were annotated for species by MetaPhlAn2. We obtained the relative abundance of species composition at the species level and genus level. The MicrobiotaProcess package was used to visualize species composition and PCA. LEfSe analysis was used to analyze the differences in the datasets in each region. Spearman correlation analysis was performed for CRC differential species. Finally, the CRC risk prediction model was constructed and verified in each regional dataset.
RESULTS
The composition of the intestinal bacterial community varied in different regions. Differential intestinal bacteria of CRC in different regions are inconsistent. There was a common diversity of bacteria in all six countries, such as Peptostreptococcus stomatis and Fusobacterium nucleatum at the species level. Peptostreptococcus stomatis (species level) and Peptostreptococcus (genus level) are important CRC-related bacteria that are related to other bacteria in different regions. Region has little influence on the accuracy of the CRC risk prediction model. Peptostreptococcus stomatis is an important variable in CRC risk prediction models in all regions.
CONCLUSION
Peptostreptococcus stomatis is a common high-risk pathogen of CRC worldwide, and it is an important variable in CRC risk prediction models in all regions. However, regional differences in intestinal bacteria had no significant impact on the accuracy of the CRC risk prediction model.
PubMed: 36578080
DOI: 10.1186/s13099-022-00524-x -
Scientific Reports Feb 2021Dysbiosis of the gut microbiome has been associated with the pathogenesis of colorectal cancer (CRC). We profiled the microbiome of gut mucosal tissues from 18 CRC... (Observational Study)
Observational Study
Dysbiosis of the gut microbiome has been associated with the pathogenesis of colorectal cancer (CRC). We profiled the microbiome of gut mucosal tissues from 18 CRC patients and 18 non-CRC controls of the UKM Medical Centre (UKMMC), Kuala Lumpur, Malaysia. The results were then validated using a species-specific quantitative PCR in 40 CRC and 20 non-CRC tissues samples from the UMBI-UKMMC Biobank. Parvimonas micra, Fusobacterium nucleatum, Peptostreptococcus stomatis and Akkermansia muciniphila were found to be over-represented in our CRC patients compared to non-CRC controls. These four bacteria markers distinguished CRC from controls (AUROC = 0.925) in our validation cohort. We identified bacteria species significantly associated (cut-off value of > 5 fold abundance) with various CRC demographics such as ethnicity, gender and CRC staging; however, due to small sample size of the discovery cohort, these results could not be further verified in our validation cohort. In summary, Parvimonas micra, Fusobacterium nucleatum, Peptostreptococcus stomatis and Akkermansia muciniphila were enriched in our local CRC patients. Nevertheless, the roles of these bacteria in CRC initiation and progression remains to be investigated.
Topics: Aged; Akkermansia; Case-Control Studies; Cohort Studies; Colorectal Neoplasms; DNA, Bacterial; Dysbiosis; Feces; Female; Firmicutes; Fusobacterium nucleatum; Gastrointestinal Microbiome; Humans; Malaysia; Male; Middle Aged; Peptostreptococcus; RNA, Ribosomal, 16S
PubMed: 33536501
DOI: 10.1038/s41598-021-82465-0 -
BMC Microbiology Sep 2020Dental implants have become well-established in oral rehabilitation for fully or partially edentulous patients. However, peri-implantitis often leads to the failure of...
BACKGROUND
Dental implants have become well-established in oral rehabilitation for fully or partially edentulous patients. However, peri-implantitis often leads to the failure of dental implants. The aim of this study was to understand the core microbiome associated with peri-implantitis and evaluate potential peri-implantitis pathogens based on canine peri-implantitis model.
RESULTS
In this study, three beagle dogs were used to build peri-implantitis models with ligature-induced strategy. The peri-implant sulcular fluids were collected at four different phases based on disease severity during the peri-implantitis development. Microbial compositions during peri-implantitis development were monitored and evaluated. The microbes were presented with operational taxonomic unit (OTU) classified at 97% identity of the high-throughput 16S rRNA gene fragments. Microbial diversity and richness varied during peri-implantitis. At the phylum-level, Firmicutes decreased and Bacteroides increased during peri-implantitis development. At the genus-level, Peptostreptococcus decreased and Porphyromonas increased, suggesting peri-implantitis pathogens might be assigned to these two genera. Further species-level and co-occurrence network analyses identified several potential keystone species during peri-implantitis development, and some OTUs were potential peri-implantitis pathogens.
CONCLUSION
In summary, canine peri-implantitis models help to identify several potential keystone peri-implantitis associated species. The canine model can give insight into human peri-implantitis associated microbiota.
Topics: Animals; Bacterial Typing Techniques; Bacteroides; Bone-Implant Interface; Dental Implants; Disease Models, Animal; Dogs; Firmicutes; Genetic Variation; Humans; Ligation; Male; Microbiota; Peptostreptococcus; Peri-Implantitis; Phylogeny; Porphyromonas; RNA, Ribosomal, 16S; Spirochaeta
PubMed: 32993514
DOI: 10.1186/s12866-020-01982-6 -
The Journal of Hygiene Aug 1981Sera from patients suffering from Crohn's and other diseases and from healthy subjects were tested for agglutinins to anaerobic, gram-positive coccoid rods belonging to... (Comparative Study)
Comparative Study
Sera from patients suffering from Crohn's and other diseases and from healthy subjects were tested for agglutinins to anaerobic, gram-positive coccoid rods belonging to species of Eubacterium and Peptostreptococcus. Four strains labelled Eubacterium contortum (two strains), Eubacterium rectale and Peptostreptococcus productus were agglutinated by a higher percentage of sera from patients with Crohn's disease than from healthy subjects and from patients with liver and intestinal diseases (including ulcerative colitis), ankylosing spondylitis, granulomatous diseases, diseases of immunity and malignancies. The agglutinins were of the IgG and IgM classes and strain-specific; the titres were low. The results obtained with sera from patients with Crohn's disease and healthy people were subjected to discriminant analysis to estimate the probability, based on the combined results with the four strains, that a patient suffers from Crohn's disease. When sera giving an a posteriori probability greater than or equal to 0.95 (a priori probability = 0.5) were considered positive, the test with four strains had a sensitivity of 54% and a specificity of nearly 100%. The results with sera submitted for diagnosis showed that positive reactions in patients with a diagnosis apparently incompatible with Crohn's disease were within acceptable limits.
Topics: Adolescent; Adult; Bacteriological Techniques; Child; Child, Preschool; Crohn Disease; Eubacterium; Gastrointestinal Diseases; Humans; Immunoglobulins; Immunologic Techniques; Infant; Peptostreptococcus; Probability
PubMed: 7019318
DOI: 10.1017/s0022172400069199 -
Uterine Commensal Species Contribute to IDO1 Induction in Endometrial Cancer via Indoleacrylic Acid.Biomedicines Mar 2024Microbial dysbiosis has an increasingly appreciated impact on carcinogenesis, and the cervicovaginal microbiome plays a critical role in microenvironmental inflammation....
Microbial dysbiosis has an increasingly appreciated impact on carcinogenesis, and the cervicovaginal microbiome plays a critical role in microenvironmental inflammation. Here, we investigated the involvement of the female genital tract species in gynecological cancer via indoleacrylic acid (IAA). IAA production from species and the effect of bacterial culture on tumor growth in vivo were examined. The impact of IAA on cytokine production and indoleamine-2,3-dioxygenase 1 (IDO1) expression in an endometrial cancer (EC) cell line, as well as their effect on T and T cells, and M1 and M2 macrophage populations were examined in EC patients and tumor-grafted mice. Clinically, species abundance, IAA, and IDO1 expression were verified in EC patients. The results showed that IAA production was induced in the uteri of BALB/c nude mice by species transplantation, and the intratumoral injection of a conditioned medium from cultures into tumor-grafted mice promoted tumor growth. IL-10 expression was upregulated by IAA; IFN-γ expression was increased by IL-10. IFN-γ induced IDO1 expression in the EC cell line. The co-culture of IDO1-expressing EC cells with peripheral blood mononuclear cells upregulated the T proportion and decreased the M1/M2 ratio. Clinically, was more abundant amongst the uterine microbiota of EC patients than the control. The IAA, IDO1, and kynurenine/tryptophan ratios were all higher in EC tissue, and the M1/M2 ratio was lower. Our study sheds light on the link between IDO1 induction and uterine dysbiosis and provides a potential rationale for the role of species in immune tolerance induction in type I endometrial cancer.
PubMed: 38540186
DOI: 10.3390/biomedicines12030573 -
Annales de Biologie Clinique 2006Linezolid is a synthetic antibiotic, the first available agent in a new class of antibiotic called the oxazolidinones, whose particular mechanism of action consists in... (Review)
Review
Linezolid is a synthetic antibiotic, the first available agent in a new class of antibiotic called the oxazolidinones, whose particular mechanism of action consists in inhibiting the initiation of protein synthesis. Its spectrum of in vitro and in vivo activity includes staphylococci, streptococci, enterococci, corynebacteria and some anaerobic bacteria (Peptostreptococcus, Clostridium, and Fusobacterium). The first therapeutic results were very encouraging, leading to the marketing of the product in France in 2002. Linezolid is indicated in the treatment of pneumonia and the complicated infections of the skin. Pharmacocinetics studies have shown that linezolid has an excellent bioavailability allowing a fast relay per os. However, failures of treatment under linezolid were reported and resistant strains of staphylococci and enterococci were obtained in vitro and in vivo after therapeutic use of this antibiotic. Changes in the domain V of 23S rRNA were found in the site of fixation, the most frequent was (G out of U) in position 2576 (numbering E. coli). In a context where resistance to traditional treatments in enterococci, pneumococci and S. aureus do not cease to increase, linezolid can be regarded as a therapeutic alternative to treat the infections with Gram-positive cocci.
Topics: Acetamides; Anti-Infective Agents; Bacteria; Bacterial Infections; Drug Resistance, Bacterial; Humans; Immunity, Innate; Linezolid; Microbial Sensitivity Tests; Oxazolidinones; Protein Synthesis Inhibitors
PubMed: 17162258
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Jun 2007Peptostreptococcus anaerobius sensu lato, currently including two closely related species, P. anaerobius and P. stomatis, is known to be more resistant than other...
Peptostreptococcus anaerobius sensu lato, currently including two closely related species, P. anaerobius and P. stomatis, is known to be more resistant than other gram-positive anaerobic cocci. We reidentified potential Peptostreptococcus isolates and tested their susceptibilities to eight antimicrobials. Notably, P. anaerobius had constantly higher values for the MIC at which 50% of the isolates are inhibited (MIC(50)) and the MIC(90) than P. stomatis.
Topics: Anaerobiosis; Anti-Bacterial Agents; Bacteremia; Gram-Positive Bacterial Infections; Humans; Microbial Sensitivity Tests; Peptostreptococcus; Species Specificity
PubMed: 17403999
DOI: 10.1128/AAC.00056-07 -
Frontiers in Microbiology 2022The gut microbial dysbiosis is a risk of colorectal cancer (CRC) and some bacteria have been reported as potential markers for CRC diagnosis. However, heterogeneity...
The gut microbial dysbiosis is a risk of colorectal cancer (CRC) and some bacteria have been reported as potential markers for CRC diagnosis. However, heterogeneity among studies with different populations and technologies lead to inconsistent results. Here, we investigated six metagenomic profiles of stool samples from healthy controls (HC), colorectal adenoma (CA) and CRC, and six and four genera were consistently altered between CRC and HC or CA across populations, respectively. In FengQ cohort, which composed with 61 HC, 47 CA, and 46 CRC samples, a random forest (RF) model composed of the six genera, denoted as signature-HC, distinguished CRC from HC with an area under the curve (AUC) of 0.84. Similarly, another RF model composed of the four universal genera, denoted as signature-CA, discriminated CRC from CA with an AUC of 0.73. These signatures were further validated in five metagenomic sequencing cohorts and six independent 16S rRNA gene sequencing cohorts. Interestingly, three genera overlapped in the two models (, and ) were with very low abundance in HC and CA, but sharply increased in CRC. A concise RF model on the three genera distinguished CRC from HC or CA with AUC of 0.87 and 0.67, respectively. Functional gene family analysis revealed that Kyoto Encyclopedia of Genes and Genomes Orthogroups categories which were significantly correlated with markers in signature-HC and signature-CA were mapped into pathways related to lipopolysaccharide and sulfur metabolism, which might be vital risk factors of CRC development. Conclusively, our study identified universal bacterial markers across populations and technologies as potential aids in non-invasive diagnosis of CRC.
PubMed: 36406447
DOI: 10.3389/fmicb.2022.1005201 -
The International Journal of Biological... Jun 2023Dysbiosis commonly occurs in pancreatic cancer, but its specific characteristics and interactions with pancreatic cancer remain obscure.
BACKGROUND
Dysbiosis commonly occurs in pancreatic cancer, but its specific characteristics and interactions with pancreatic cancer remain obscure.
MATERIALS AND METHODS
The 16S rRNA sequencing method was used to analyze multisite (oral and gut) microbiota characteristics of pancreatic cancer, chronic pancreatitis, and healthy controls. Differential analysis was used to identify the pancreatic cancer-associated genera and pathways. A random forest algorithm was adopted to establish the diagnostic models for pancreatic cancer.
RESULTS
The chronic pancreatitis group exhibited the lowest microbial diversity, while no significant difference was found between the pancreatic cancer group and healthy controls group. Diagnostic models based on the characteristics of the oral (area under the curve (AUC) 0.916, 95% confidence interval (CI) 0.832-1) or gut (AUC 0.856; 95% CI 0.74, 0.972) microbiota effectively discriminate the pancreatic cancer samples in this study, suggesting saliva as a superior sample type in terms of detection efficiency and clinical compliance. Oral pathogenic genera (, , , , etc.) and gut opportunistic genera (, , , , , etc.), were significantly enriched in pancreatic cancer. The 16S function prediction analysis revealed that inflammation, immune suppression, and barrier damage pathways were involved in the course of pancreatic cancer.
CONCLUSION
This study comprehensively described the microbiota characteristics of pancreatic cancer and suggested potential microbial markers as non-invasive tools for pancreatic cancer diagnosis.
Topics: Humans; Bacteria; RNA, Ribosomal, 16S; Microbiota; Pancreatic Neoplasms; Pancreatitis, Chronic
PubMed: 37017014
DOI: 10.1177/03936155231166721