RESUMEN
Fusobacteria have been associated to different diseases, including colorectal cancer (CRC), but knowledge of which taxonomic groups contribute to specific conditions is incomplete. We analyzed the genetic diversity and relationships within the Fusobacterium genus. We report recent and ancestral recombination in core genes, indicating that fusobacteria have mosaic genomes and emphasizing that taxonomic demarcation should not rely on single genes/gene regions. Across databases, we found ample evidence of species miss-classification and of undescribed species, which are both expected to complicate disease association. By focusing on a lineage that includes F. periodonticum/pseudoperiodonticum and F. nucleatum, we show that genomes belong to four modern populations, but most known species/subspecies emerged from individual ancestral populations. Of these, the F. periodonticum/pseudoperiodonticum population experienced the lowest drift and displays the highest genetic diversity, in line with the less specialized distribution of these bacteria in oral sites. A highly drifted ancestral population instead contributed genetic ancestry to a new species, which includes genomes classified within the F. nucleatum animalis diversity in a recent CRC study. Thus, evidence herein calls for a re-analysis of F. nucleatum animalis features associated to CRC. More generally, our data inform future molecular profiling approaches to investigate the epidemiology of Fusobacterium-associated diseases.
Asunto(s)
Fusobacterium , Genoma Bacteriano , Genómica , Filogenia , Fusobacterium/genética , Fusobacterium/clasificación , Genómica/métodos , Variación Genética , Humanos , Infecciones por Fusobacterium/microbiología , Infecciones por Fusobacterium/genéticaRESUMEN
We examined Fusobacterium nucreatum (F. nucleatum) and whole Fusobacterium species (Pan-fusobacterium) in non-neoplastic Barrett's esophagus (BE) from patients without cancer (n = 67; N group), with esophageal adenocarcinoma (EAC) (n = 27) and EAC tissue (n = 22). F. nucleatum was only detectable in 22.7% of EAC tissue. Pan-fusobacterium was enriched in EAC tissue and associated with aggressive clinicopathological features. Amount of Pan-fusobacterium in non-neoplastic BE was correlated with presence of hital hernia and telomere shortening. The result suggested potential association of Fusobacterium species in EAC and BE, featuring clinicpathological and molecular features.
Asunto(s)
Adenocarcinoma , Esófago de Barrett , Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/microbiología , Neoplasias Esofágicas/patología , Adenocarcinoma/microbiología , Adenocarcinoma/patología , Esófago de Barrett/microbiología , Esófago de Barrett/patología , Masculino , Persona de Mediana Edad , Femenino , Anciano , Fusobacterium/aislamiento & purificación , Fusobacterium/genética , Fusobacterium nucleatum/aislamiento & purificación , AdultoRESUMEN
Introduction: Microbial community composition is closely associated with host disease onset and progression, underscoring the importance of understanding host-microbiota dynamics in various health contexts. Methods: In this study, we utilized full-length 16S rRNA gene sequencing to conduct species-level identification of the microorganisms in the oral cavity of a giant panda (Ailuropoda melanoleuca) with oral malignant fibroma. Results: We observed a significant difference between the microbial community of the tumor side and non-tumor side of the oral cavity of the giant panda, with the latter exhibiting higher microbial diversity. The tumor side was dominated by specific microorganisms, such as Fusobacterium simiae, Porphyromonas sp. feline oral taxon 110, Campylobacter sp. feline oral taxon 100, and Neisseria sp. feline oral taxon 078, that have been reported to be associated with tumorigenic processes and periodontal diseases in other organisms. According to the linear discriminant analysis effect size analysis, more than 9 distinct biomarkers were obtained between the tumor side and non-tumor side samples. Furthermore, the Kyoto Encyclopedia of Genes and Genomes analysis revealed that the oral microbiota of the giant panda was significantly associated with genetic information processing and metabolism, particularly cofactor and vitamin, amino acid, and carbohydrate metabolism. Furthermore, a significant bacterial invasion of epithelial cells was predicted in the tumor side. Discussion: This study provides crucial insights into the association between oral microbiota and oral tumors in giant pandas and offers potential biomarkers that may guide future health assessments and preventive strategies for captive and aging giant pandas.
Asunto(s)
Campylobacter , Fusobacterium , Microbiota , Boca , Porphyromonas , ARN Ribosómico 16S , Ursidae , Ursidae/microbiología , Animales , ARN Ribosómico 16S/genética , Porphyromonas/genética , Porphyromonas/aislamiento & purificación , Porphyromonas/clasificación , Campylobacter/genética , Campylobacter/aislamiento & purificación , Campylobacter/clasificación , Boca/microbiología , Fusobacterium/genética , Fusobacterium/aislamiento & purificación , Fibroma/microbiología , Fibroma/veterinaria , Neisseria/aislamiento & purificación , Neisseria/genética , Neisseria/clasificación , Neoplasias de la Boca/microbiología , Neoplasias de la Boca/veterinaria , Neoplasias de la Boca/patología , Filogenia , Análisis de Secuencia de ADNAsunto(s)
Biomarcadores , Fusobacterium , Microbiota , Periodontitis , Saliva , Humanos , Saliva/microbiología , Periodontitis/microbiología , Periodontitis/diagnóstico , Biomarcadores/análisis , Fusobacterium/aislamiento & purificación , Fusobacterium/genética , Adulto , Femenino , ARN Ribosómico 16S/metabolismo , ARN Ribosómico 16S/genética , Persona de Mediana Edad , Masculino , Curva ROCRESUMEN
Fusobacterium nucleatum is an anaerobic commensal of the oral cavity associated with periodontitis and extra-oral diseases, including colorectal cancer. Previous studies have shown an increased relative abundance of this bacterium associated with oral dysplasia or within oral tumours. Using direct culture, we found that 75â% of Fusobacterium species isolated from malignant or potentially malignant oral mucosa were F. nucleatum subsp. polymorphum. Whole genome sequencing and pangenome analysis with Panaroo was carried out on 76 F. nucleatum subsp. polymorphum genomes. F. nucleatum subsp. polymorphum was shown to possesses a relatively small core genome of 1604 genes in a pangenome of 7363 genes. Phylogenetic analysis based on the core genome shows the isolates can be separated into three main clades with no obvious genotypic associations with disease. Isolates recovered from healthy and diseased sites in the same patient are generally highly related. A large repertoire of adhesins belonging to the type V secretion system (TVSS) could be identified with major variation in repertoire and copy number between strains. Analysis of intergenic recombination using fastGEAR showed that adhesin complement is shaped by horizontal gene transfer and recombination. Recombination events at TVSS adhesin genes were not only common between lineages of subspecies polymorphum, but also between different subspecies of F. nucleatum. Strains of subspecies polymorphum with low copy numbers of TVSS adhesin encoding genes tended to have the weakest adhesion to oral keratinocytes. This study highlights the genetic heterogeneity of F. nucleatum subsp. polymorphum and provides a new framework for defining virulence in this organism.
Asunto(s)
Transferencia de Gen Horizontal , Mosaicismo , Humanos , Filogenia , Fusobacterium/genética , Fenotipo , Dosificación de GenRESUMEN
The incidence of colorectal cancer (CRC) has increased worldwide, and early diagnosis is crucial to reduce mortality rates. Therefore, new noninvasive biomarkers for CRC are required. Recent studies have revealed an imbalance in the oral and gut microbiomes of patients with CRC, as well as impaired gut vascular barrier function. In the present study, the microbiomes of saliva, crevicular fluid, feces, and non-neoplastic and tumor intestinal tissue samples of 93 CRC patients and 30 healthy individuals without digestive disorders (non-CRC) were analyzed by 16S rRNA metabarcoding procedures. The data revealed that Parvimonas, Fusobacterium, and Bacteroides fragilis were significantly over-represented in stool samples of CRC patients, whereas Faecalibacterium and Blautia were significantly over-abundant in the non-CRC group. Moreover, the tumor samples were enriched in well-known periodontal anaerobes, including Fusobacterium, Parvimonas, Peptostreptococcus, Porphyromonas, and Prevotella. Co-occurrence patterns of these oral microorganisms were observed in the subgingival pocket and in the tumor tissues of CRC patients, where they also correlated with other gut microbes, such as Hungatella. This study provides new evidence that oral pathobionts, normally located in subgingival pockets, can migrate to the colon and probably aggregate with aerobic bacteria, forming synergistic consortia. Furthermore, we suggest that the group composed of Fusobacterium, Parvimonas, Bacteroides, and Faecalibacterium could be used to design an excellent noninvasive fecal test for the early diagnosis of CRC. The combination of these four genera would significantly improve the reliability of a discriminatory test with respect to others that use a single species as a unique CRC biomarker.
Asunto(s)
Bacteroides , Biomarcadores de Tumor , Neoplasias Colorrectales , Heces , Fusobacterium , Humanos , Neoplasias Colorrectales/microbiología , Neoplasias Colorrectales/diagnóstico , Fusobacterium/aislamiento & purificación , Fusobacterium/genética , Masculino , Femenino , Bacteroides/aislamiento & purificación , Bacteroides/genética , Persona de Mediana Edad , Heces/microbiología , Faecalibacterium/aislamiento & purificación , Faecalibacterium/genética , Anciano , ARN Ribosómico 16S/genética , Microbioma Gastrointestinal/genética , Saliva/microbiología , AdultoRESUMEN
BACKGROUND: Aquaculture plays an important role in global protein supplies and food security. The ban on antibiotics as feed additive proposes urgent need to develop alternatives. Gut microbiota plays important roles in the metabolism and immunity of fish and has the potential to give rise to novel solutions for challenges confronted by fish culture. However, our understanding of fish gut microbiome is still lacking. RESULTS: We identified 575,856 non-redundant genes by metagenomic sequencing of the intestinal content samples of grass carp. Taxonomic and functional annotation of the gene catalogue revealed specificity of the gut microbiome of grass carp compared with mammals. Co-occurrence analysis indicated exclusive relations between the genera belonging to Proteobacteria and Fusobacteria/Firmicutes/Bacteroidetes, suggesting two independent ecological groups of the microbiota. The association pattern of Proteobacteria with the gene expression modules of fish gut and the liver was consistently opposite to that of Fusobacteria, Firmicutes, and Bacteroidetes, implying differential functionality of Proteobacteria and Fusobacteria/Firmicutes/Bacteroidetes. Therefore, the two ecological groups were considered as two functional groups, i.e., Functional Group 1: Proteobacteria and Functional Group 2: Fusobacteria/Firmicutes/Bacteroidetes. Further analysis revealed that the two functional groups differ in genetic capacity for carbohydrate utilization, virulence factors, and antibiotic resistance. Finally, we proposed that the ratio of "Functional Group 2/Functional Group 1" can be used as a biomarker that efficiently reflects the structural and functional characteristics of the microbiota of grass carp. CONCLUSIONS: The gene catalogue is an important resource for investigating the gut microbiome of grass carp. Multi-omics analysis provides insights into functional implications of the main phyla that comprise the fish microbiota and shed lights on targets for microbiota regulation. Video Abstract.
Asunto(s)
Carpas , Microbioma Gastrointestinal , Microbiota , Animales , Microbioma Gastrointestinal/genética , Multiómica , Proteobacteria/genética , Fusobacterias/genética , Bacteroidetes/genética , Firmicutes/genética , Fusobacterium/genética , ARN Ribosómico 16S/genética , Mamíferos/genéticaRESUMEN
Esophageal carcinoma (ESCA) is a leading cause of cancer-related death worldwide, and certain oral and intestinal pathogens have been associated with cancer development and progression. We asked if esophageal microbiomes had shared alterations that could provide novel biomarkers for ESCA risk. We extracted DNA from tumor and non-tumor tissue of 212 patients in the NCI-MD case control study and sequenced the 16S rRNA gene (V3-4), with TCGA ESCA RNA-seq (n = 172) and WGS (n = 123) non-human reads used as validation. We identified four taxa, Campylobacter, Prevotella, Streptococcus, and Fusobacterium as highly enriched in esophageal cancer across all cohorts. Using SparCC, we discovered that Fusobacterium and Prevotella were also co-enriched across all cohorts. We then analyzed immune cell infiltration to determine if these dysbiotic taxa were associated with immune signatures. Using xCell to obtain predicted immune infiltrates, we identified a depletion of megakaryocyte-erythroid progenitor (MEP) cells in tumors with presence of any of the four taxa, along with enrichment of platelets in tumors with Campylobactor or Fusobacterium. Taken together, our results suggest that intratumoral presence of these co-occurring bacterial genera may confer tumor promoting immune alterations that allow disease progression in esophageal cancer.
Asunto(s)
Neoplasias Esofágicas , Humanos , Estudios de Casos y Controles , ARN Ribosómico 16S/genética , Fusobacterium/genética , PlaquetasRESUMEN
Background and purpose: When it comes to the onset of moyamoya disease (MMD), environmental variables are crucial. Furthermore, there is confusion about the relationship between the gut microbiome, an environmental variable, and MMD. Consequently, to identify the particular bacteria that cause MMD, we examined the gut microbiome of MMD individuals and healthy controls (HC). Methods: A prospective case-control investigation was performed from June 2021 to May 2022. The fecal samples of patients with MMD and HC were obtained. Typically, 16S rRNA sequencing was employed to examine their gut microbiota. The QIIME and R softwares were used to examine the data. The linear discriminant analysis effect size analysis was used to determine biomarkers. Multivariate analysis by linear models (MaAsLin)2 were used to find associations between microbiome data and clinical variables. Model performance was assessed using the receiver operating characteristic curve and the decision curve analysis. Results: This investigation involved a total of 60 MMD patients and 60 HC. The MMD group's Shannon and Chao 1 indices were substantially lower than those of the HC cohort. ß-diversity was significantly different in the weighted UniFrac distances. At the phylum level, the relative abundance of Fusobacteriota/Actinobacteria was significantly higher/lower in the MMD group than that in the HC group. By MaAsLin2 analysis, the relative abundance of the 2 genera, Lachnoclostridium and Fusobacterium, increased in the MMD group, while the relative abundance of the 2 genera, Bifidobacterium and Enterobacter decreased in the MMD group. A predictive model was constructed by using these 4 genera. The area under the receiver operating characteristic curve was 0.921. The decision curve analysis indicated that the model had usefulness in clinical practice. Conclusions: The gut microbiota was altered in individuals with MMD, and was characterized by increased abundance of Lachnoclostridium and Fusobacterium and decreased abundance of Bifidobacterium and Enterobacter. These 4 genera could be used as biomarkers and predictors in clinical practice.
Asunto(s)
Microbioma Gastrointestinal , Enfermedad de Moyamoya , Humanos , Adulto , ARN Ribosómico 16S/genética , Heces/microbiología , Bacterias/genética , Fusobacterium/genética , Biomarcadores , BifidobacteriumRESUMEN
There is currently an urgent need to identify factors predictive of immunogenicity in colorectal cancer (CRC). Mucinous CRC is a distinct histological subtype of CRC, associated with a poor response to chemotherapy. Recent evidence suggests the commensal facultative anaerobe Fusobacterium may be especially prevalent in mucinous CRC. The objectives of this study were to assess the association of Fusobacterium abundance with immune cell composition and prognosis in mucinous CRC. Our study included two independent colorectal cancer patient cohorts, The Cancer Genome Atlas (TCGA) cohort, and a cohort of rectal cancers from the Beaumont RCSI Cancer Centre (BRCC). Multiplexed immunofluorescence staining of a tumour microarray (TMA) from the BRCC cohort was undertaken using Cell DIVE technology. Our cohorts included 87 cases (13.3%) of mucinous and 565 cases (86.7%) of non-mucinous CRC. Mucinous CRC in the TCGA dataset was associated with an increased proportion of CD8 + lymphocytes (p = 0.018), regulatory T-cells (p = 0.001) and M2 macrophages (p = 0.001). In the BRCC cohort, mucinous RC was associated with enhanced CD8 + lymphocyte (p = 0.022), regulatory T-cell (p = 0.047), and B-cell (p = 0.025) counts. High Fusobacterium abundance was associated with an increased proportion of CD4 + lymphocytes (p = 0.031) and M1 macrophages (p = 0.006), whilst M2 macrophages (p = 0.043) were under-represented in this cohort. Patients with increased Fusobacterium relative abundance in our mucinous CRC TCGA cohort tended to have better clinical outcomes (DSS: likelihood ratio p = 0.04, logrank p = 0.052). Fusobacterium abundance may be associated with improved outcomes in mucinous CRC, possibly due to a modulatory effect on the host immune response. KEY MESSAGES: ⢠Increased Fusobacterium relative abundance was not found to be associated with microsatellite instability in mucinous CRC. ⢠Increased Fusobacterium relative abundance was associated with an M2/M1 macrophage switch, which is especially significant in mucinous CRC, where M2 macrophages are overexpressed. ⢠Increased Fusobacterium relative abundance was associated with a significant improvement in disease specific survival in mucinous CRC. ⢠Our findings were validated at a protein level within our own in house mucinous and non-mucinous rectal cancer cohorts.
Asunto(s)
Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Fusobacterium/genética , Neoplasias Colorrectales/metabolismo , Inestabilidad de Microsatélites , Macrófagos/metabolismoRESUMEN
Fusobacterium varium has been generally overlooked in cattle rumen microbiome studies relative to the presumably more abundant liver abscess-causing Fusobacterium necrophorum. However, F. varium was found to be more abundant in the rumen fluid of cattle and under culture conditions tailored to enrich F. necrophorum. Using near-full length 16S ribosomal ribonucleic acid sequencing, we demonstrate that F. varium grows under restrictive conditions commonly used to enumerate F. necrophorum, suggesting that previous F. necrophorum abundance assessment may have been inaccurate and that F. varium may be an underestimated member of the ruminal bacterial community. Fusobacterium varium were not as susceptible as F. necrophorum to in-feed antibiotics conventionally used in feedlots. Exposure to tylosin, the current gold standard for liver abscess reduction strategies in cattle, consistently hindered growth of the F. necrophorum strains tested by over 67% (Pâ <â 0.05) relative to the unexposed control. In contrast, F. varium strains were totally or highly resistant (0%-13% reduction in maximum yield, Pâ <â 0.05). Monensin, an ionophore antibiotic, had greater inhibitory activity against F. necrophorum than F. varium. Finally, preliminary genomic analysis of two F. varium isolates from the rumen revealed the presence of virulence genes related to those of pathogenic human F. varium isolates associated with active invasion of mammalian cells. The data presented here encourage further investigation into the ecological role of F. varium within the bovine rumen and potential role in liver abscess development, and proactive interventions.
The conventional method of liver abscess prevention in feedlot cattle is in-feed use of tylosin to target Fusobacterium necrophorum, which has been presumed to be the most common Fusobacterium species within the ruminal compartment. Our investigation into ruminal Fusobacterium, however, revealed a different species, Fusobacterium varium, to be abundant and ubiquitous in ruminal content samples. Furthermore, growth conditions tailored to enrich F. necrophorum consistently promoted growth of F. varium, and the bovine isolates tested had much lower susceptibilities to the commonly fed antibiotics tylosin and monensin compared to F. necrophorum. Fusobacterium varium is an emerging pathogen in humans and preliminary genome sequencing of two ruminal F. varium isolates revealed genes linked to pathogenicity. While the ecological role of F. varium in the rumen is still not fully understood, our findings draw attention to this pathogen and its potential implication in liver abscesses.
Asunto(s)
Enfermedades de los Bovinos , Absceso Hepático , Humanos , Bovinos , Animales , Rumen/microbiología , Fusobacterium/genética , Antibacterianos/farmacología , Absceso Hepático/veterinaria , Absceso Hepático/microbiología , Enfermedades de los Bovinos/microbiología , MamíferosRESUMEN
The genus Fusobacterium contains currently 13 species presenting as non-sporing, obligate anaerobic, Gram-negative fusiform rods. Fusobacterium ulcerans was discovered in 1988 causing tropical ulcers. We present the case of a patient with diverticulitis complicated with bacteremia. Both aerobic bottles were positive at 20 and 24 h, while one anaerobic bottle was positive at 36 h. Escherichia coli and Fusobacterium ulcerans were identified from subcultures by MALDI-TOF MS with a score of 2.02 and 2.35, respectively. The 16S rRNA gene was sequenced in order to confirm the identification of F. ulcerans with a 100% homology to the reference strain. The patient was treated with 4 g/0,5 g of IV piperacillin/tazobactam and later with 1 g/0,2 g of amoxicillin/clavulanic during 7 days with good clinical evolution.
Asunto(s)
Bacteriemia , Traslocación Bacteriana , Humanos , ARN Ribosómico 16S/genética , Fusobacterium/genética , Bacteriemia/microbiología , Bacterias Gramnegativas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
While the association between colorectal cancer (CRC) features and Fusobacterium has been extensively studied, less is known of other intratumoral bacteria. Here, we leverage whole transcriptomes from 807 CRC samples to dually characterize tumor gene expression and 74 intratumoral bacteria. Seventeen of these species, including 4 Fusobacterium spp., are classified as orally derived and are enriched among right-sided, microsatellite instability-high (MSI-H), and BRAF-mutant tumors. Across consensus molecular subtypes (CMSs), integration of Fusobacterium animalis (Fa) presence and tumor expression reveals that Fa has the most significant associations in mesenchymal CMS4 tumors despite a lower prevalence than in immune CMS1. Within CMS4, the prevalence of Fa is uniquely associated with collagen- and immune-related pathways. Additional Fa pangenome analysis reveals that stress response genes and the adhesion FadA are commonly expressed intratumorally. Overall, this study identifies oral-derived bacteria as enriched in inflamed tumors, and the associations of bacteria and tumor expression are context and species specific.
Asunto(s)
Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/genética , Fusobacterium/genética , Inestabilidad de Microsatélites , TranscriptomaRESUMEN
Odontogenic rhinosinusitis is a subtype of rhinosinusitis associated with dental infection or dental procedures and has special bacteriologic features. Previous research on the bacteriologic features of odontogenic rhinosinusitis has mainly used culture-dependent methods. The variation of microbiota between odontogenic and nonodontogenic rhinosinusitis as well as the interplay between the involved bacteria have not been explored. Therefore, we enrolled eight odontogenic rhinosinusitis cases and twenty nonodontogenic rhinosinusitis cases to analyze bacterial microbiota through 16S rRNA sequencing. Significant differences were revealed by the Shannon diversity index (Wilcoxon test p = 0.0003) and PERMANOVA test based on weighted UniFrac distance (Wilcoxon test p = 0.001) between odontogenic and nonodontogenic samples. Anaerobic bacteria such as Porphyromonas, Fusobacterium, and Prevotella were significantly dominant in the odontogenic rhinosinusitis group. Remarkably, a correlation between different bacteria was also revealed by Pearson's correlation. Staphylococcus was highly positively associated with Corynebacterium, whereas Fusobacterium was highly negatively correlated with Prophyromonas. According to our results, the microbiota in odontogenic rhinosinusitis, predominantly anaerobic bacteria, was significantly different from that in nonodontogenic rhinosinusitis, and the interplay between specific bacteria may a major cause of this subtype of rhinosinusitis.
Asunto(s)
Microbiota , Sinusitis , Humanos , Disbiosis/complicaciones , Disbiosis/microbiología , ARN Ribosómico 16S/genética , Bacterias Anaerobias/genética , Sinusitis/complicaciones , Sinusitis/microbiología , Bacterias/genética , Fusobacterium/genéticaRESUMEN
PURPOSE: Fusobacterium species can cause infections, and associations with cancer are being increasingly reported. As their clinical significance differs, accurate identification of individual species is important. However, matrix-assisted laser desorption/ionization-time of flight mass spectrometry has not been found to be effective in identifying Fusobacterium species in previous studies. In this study, we aimed to improve the accuracy and efficacy of identifying Fusobacterium species in clinical laboratories. MATERIALS AND METHODS: In total, 229 Fusobacterium isolates were included in this study. All isolates were identified at the species level based on nucleotide sequences of the 16S ribosomal RNA gene and/or DNA-dependent RNA polymerase ß-subunit gene (rpoB). Where necessary, isolates were identified based on whole genome sequences. Among them, 47 isolates were used for updating the ASTA database, and 182 isolates were used for the validation of Fusobacterium spp. identification. RESULTS: Fusobacterium isolates used for validation (182/182) were correctly identified at the genus level, and most (180/182) were correctly identified at the species level using the ASTA MicroIDSys system. Most of the F. nucleatum isolates (74/75) were correctly identified at the subspecies level. CONCLUSION: The updated ASTA MicroIDSys system can identify nine species of Fusobacterium and four subspecies of F. nucleatum in good agreement. This tool can be routinely used in clinical microbiology laboratories to identify Fusobacterium species and serve as a springboard for future research.
Asunto(s)
Fusobacterium , Laboratorios Clínicos , Humanos , Fusobacterium/genética , Espectrometría de Masas , Bases de Datos Factuales , Rayos LáserRESUMEN
INTRODUCTION: Fusobacterium and several bacteria are reported to be associated with colorectal cancer (CRC). However, their relationship and whether they cause CRC or are just adapted to the cancerous environment is not known. We approached this subject by investigating the correlation and distribution of the bacteria throughout the colon in patients with CRC and elucidated the relationship between microbiota and CRC. METHODS: Twenty-five patients with CRC who underwent colonoscopy for endoscopic submucosal dissection or surgery were prospectively enrolled. Fecal samples were taken before bowel preparation, and mucosal samples were collected from three sites (tumor surface, tumor-adjacent mucosa, and cecum) during colonoscopy using a cytology brush. The microbiota was identified and analyzed by sequencing of the 16S rRNA gene of the V3-V4 region. We evaluated the correlation between the bacteria based on network analysis and the distribution of Fusobacterium in the colon. RESULTS: A network consisting of many bacteria was found in all sites; especially, oral origin bacteria including Fusobacterium formed a positively correlated network on tumor surface. Streptococcus showed a significantly higher relative abundance on tumor surface than in feces. The relative abundance of Fusobacterium had significant positive correlations between tumor surface and feces, tumor-adjacent mucosa, and cecum. CONCLUSION: In patients with CRC, many bacteria were correlated with each other, and Fusobacterium and oral origin bacteria formed a positively correlated network on tumor surface. Fusobacterium was equally distributed on tumor surface and throughout the lumen and mucus in the colon. In the colon where Fusobacterium is widely distributed, Fusobacterium would adhere to the tumor surface and be correlated with oral origin bacteria to make a microenvironment that is favorable for CRC.
Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Microbiota , Humanos , Fusobacterium/genética , ARN Ribosómico 16S/genética , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/patología , Heces/microbiología , Bacterias/genética , Membrana Mucosa/patología , Microambiente TumoralRESUMEN
Perturbations in the gut microbiome have been associated with colorectal cancer (CRC), with the colonic overabundance of Fusobacterium nucleatum shown as the most consistent marker. Despite its significance in the promotion of CRC, genomic studies of Fusobacterium is limited. We enrolled 43 Vietnamese CRC patients and 25 participants with non-cancerous colorectal polyps to study the colonic microbiomes and genomic diversity of Fusobacterium in this population, using a combination of 16S rRNA gene profiling, anaerobic microbiology, and whole genome analysis. Oral bacteria, including F. nucleatum and Leptotrichia, were significantly more abundant in the tumour microbiomes. We obtained 53 Fusobacterium genomes, representing 26 strains, from the saliva, tumour and non-tumour tissues of six CRC patients. Isolates from the gut belonged to diverse F. nucleatum subspecies (nucleatum, animalis, vincentii, polymorphum) and a potential new subspecies of Fusobacterium periodonticum. The Fusobacterium population within each individual was distinct and in some cases diverse, with minimal intra-clonal variation. Phylogenetic analyses showed that within four individuals, tumour-associated Fusobacterium were clonal to those isolated from non-tumour tissues. Genes encoding major virulence factors (Fap2 and RadD) showed evidence of horizontal gene transfer. Our work provides a framework to understand the genomic diversity of Fusobacterium within the CRC patients, which can be exploited for the development of CRC diagnostic and therapeutic options targeting this oncobacterium.
Asunto(s)
Neoplasias Colorrectales , Microbiota , Humanos , ARN Ribosómico 16S/genética , Filogenia , Fusobacterium/genética , Genómica , Neoplasias Colorrectales/microbiología , Pueblo AsiaticoRESUMEN
OBJECTIVE: Although anaerobic bacteria are important agents of a wide variety of serious infections, they are overlooked often in the etiology of infection due to difficulties in isolation and detection. The aim of this study was to develop a new multiplex PCR panel that could detect Bacteroides, Fusobacterium, Prevotella, Veillonella, Clostridium, Peptostreptococcus, and Actinomyces bacteria, which are the most frequently isolated from anaerobic infections, at the genus level. METHOD: Aerobic and anaerobic cultures were performed on 46 clinical specimens, with suspicion of anaerobic infection and were sent to the laboratory. DNA isolation was performed with the same samples and anaerobic bacteria were detected by the multiplex PCR test developed in the study. RESULT: The analytical sensitivity of the multiplex PCR assay was found to be 1-103 CFU/ml, depending on the bacterial species. In this study, anaerobic growth was observed in eight (17.4%) of 46 clinical samples. The multiplex PCR test detected 35 anaerobic bacteria from 20 (43.5%) of 46 clinical samples. The most common anaerobes isolated from clinical specimens by the multiplex PCR assay were Prevotella spp. (37.1%) and Fusobacterium spp. (22.9%) while Clostridium spp. (14.3%), Peptostreptococcus spp. (11.4%), Bacteroides spp. (8.6%), and Veillonella spp. (5.7%) followed these genera. CONCLUSION: As a result, it was concluded that the multiplex PCR panel developed in this study eliminates problems in the detection of anaerobes based on culture, provides more accurate detection of anaerobic bacteria from clinical specimens, takes a shorter time, and allows more accurate infection treatment.
Asunto(s)
Bacterias Anaerobias , Infecciones Bacterianas , Bacterias/genética , Infecciones Bacterianas/microbiología , Clostridium , Fusobacterium/genética , Humanos , Reacción en Cadena de la Polimerasa MultiplexRESUMEN
Recently, increased number of studies have demonstrated a relationship between the oral microbiome and development of head and neck cancer, however, there are few studies to investigate the role of oral bacteria in the context of the tumor microenvironment in a single head and neck subsite. Here, paired tumor and adjacent normal tissues from thirty-seven oral tongue squamous cell carcinoma (SCC) patients were subjected to 16S rRNA gene sequencing and whole exome sequencing (WES), in addition to RNA sequencing for tumor samples. We observed that Fusobacterium was significantly enriched in oral tongue cancer and that Rothia and Streptococcus were enriched in adjacent normal tissues. A decrease in alpha diversity was found in tumor when compared to adjacent normal tissues. While increased Fusobacterium in tumor samples was not associated with changes in immune cell infiltration, it was associated with increased PD-L1 mRNA expression. Therefore, we examined the effects of Fusobacterium on PD-L1 expression in head and neck SCC cell lines. We demonstrated that infection with Fusobacterium species can increase both PD-L1 mRNA and surface PD-L1 protein expression on head and neck cancer cell lines. The correlation between Fusobacterium and PD-L1 expression in oral tongue SCC, in conjunction with the ability of the bacterium to induce PD-L1 expression in vitro suggests a potential role for Fusobacterium on modulation of the tumor immune microenvironment in head and neck cancer.