Comparing the microbiota composition of stool, intestinal biopsy and saliva between patients with Adenoma and Adenocarcinoma
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ABSTRACT: Increasing importance in the onset and progression from colonic adenomatous polyps (AP) to colorectal cancer (CRC) has been attributed to the gut microbiota and the oncometabolites they may produce. To comprehensively study the microbial spatial variations and role of microbiota in CRC progression, multiple niches from the gastrointestinal system have to be investigated. We collected saliva, tissue and stool samples from 61 patients, including 46 CRC patients and 15 AP patients, well matched in age and sex, who were undergoing surgery in 2018 at the Careggi University Hospital (Florence, Italy). For all samples and locations we surveyed microbial composition through 16S ribosomal RNA and metabolites using NMR, and compared them across tissues and disease state, also considering CRC TNM staging. Our result suggest the importance of microbiota communities and derived oncometabolites in CRC development. Such association can be a forerunner for future studies on CRC/AP management.
Project description:Dysbiotic configurations of the human gut microbiota have been linked with colorectal cancer (CRC). Human small non-coding RNAs are also implicated in CRC and recent findings suggest that their release in the gut lumen contributes to shape the gut microbiota. Bacterial small RNAs (bsRNAs) may also play a role in carcinogenesis but their role is less explored. Here, we performed small RNA and shotgun sequencing on 80 stool specimens of patients with CRC, or adenomas, and healthy subjects collected in a cross-sectional study to evaluate their combined use as a predictive tool for disease detection. We reported a considerable overlap and correlation between metagenomic and bsRNA quantitative taxonomic profiles obtained from the two approaches. Furthermore, we identified a combined predictive signature composed by 32 features from human and microbial small RNAs and DNA-based microbiome able to accurately classify CRC from healthy and adenoma samples (AUC= 0.87). In summary we reported evidence that host-microbiome dysbiosis in CRC can be observed also by altered small RNA stool profiles. Integrated analyses of the microbiome and small RNAs in the human stool may provide insights for designing more accurate tools for diagnostic purposes.
Project description:Familial Mediterranean fever (FMF) is an inflammatory genetic disease characterized by elevated systemic reactivity against commensal gut microbiota and high levels of gut Candida albicans. The current study investigated the effects of Lactobacillus acidophillus INMIA 9602 Er 317/402 strain (probiotic “Narine”) on the relative abundance of gut enteric bacteria, lactobacilli, Staphylococcus aureus, and Enteroccocus faecalis in Candida albicans-carrier and non-carrier FMF patients in remission with the main MEFV mutation patterns M694V/V726A- the prevalent MEFV gene mutation within FMF patients in the Armenian cohort. Our data revealed that M694V/V726A mutations in PURIN inflammasome leading to FMF disease brought to gender specific differences in microbial community structure in FMF patients. Possibly, long-term colchicine use suppresses the PURIN inflammasome/inhibits NLRP3 inflammasome-dependent IL-1β release influencing on overgrowth of C. albicans in gut microbiota of FMF patients. The comparison of Operational Taxonomic Units (OTUs) of enteric bacteria in C. albicans-carrier and non-carrier female patients revealed the statistically significant increase in OTUs of enterobacteria in C. albicans-carriers. In contrast to this, there were no differences in abundance of Enteroccocus faecalis between female FMF C. albicans-carriers compared with non-carriers, while male FMF C. albicans-carriers have increased abundance of E. faecalis in their gut microbiota compared with that of male patients with none carriers. The gut microbiota of FMF patients (both male and female) with C. albicans below baseline level contains high abundance of lactobacilli compared with C. albicans-carriers. The adoption of Lactobacillus acidophilus INMIA 9602 Er 317/402 leads to changes in gut microbiota composition of FMF patients. It reduces, in particularly, the abundance of enterobacteria in females, and Enteroccocus faecalis in men parallel with reducing the numbers of yeast in gut microbiota of FMF patients. We hypothesize that colchicine treatment changes the already-altered gut microbiota of FMF patients, thereby affecting the regulation of immune system by inhibition of NLRP3 inflammasome. Colchicine could lead to overgrowth of C. albicans in gut microbiota of FMF patients, whereas the Lactobacillus acidophilus INMIA 9602 Er 317/402 works on activation of inflammasome by new changes in gut microbiota of patients.
Project description:Several lines of evidence suggest that inflammation plays a pivotal role in the development and progression of CRC and can be unleashed by the loss of innate immunosurveillance. The complement system is a well characterized first line of defense against pathogens and a central component of the immune responses. As such, the complement system is an important determinant in the maintenance of intestinal homeostasis and emerging evidences suggest that complement dysregulation is involved in the development and progression of CRC. Here we show that in CRC patients CpG island methylation occurs in the gene encoding for the complement anaphylatoxin C3a receptor (c3aR) and strong C3aR down-regulation resulted in decreased overall survival and events-free survival in CRC patients. Ablation of c3ar in mouse models of CRC resulted in the establishment of a pro-inflammatory microbial flora, which fostered strong Th1/Th17 immune responses and a striking increase in tumor incidence and growth that were both dependent on the microbiota. Our findings highlight a previously unrecognized tumor oncosuppressive role for C3aR in CRC that could be exploited as a biomarker for more effective therapeutic intervention.
Project description:Intestinal microorganisms impact on health maintaining gut homeostasis and shaping the host immunity, while gut dysbiosis associates with many conditions including autism, a complex neurodevelopmental disorder with multifactorial aetiology. In autism, gut dysbiosis correlates with symptom severity and is characterized by a reduced bacterial variability and a diminished beneficial commensal relationship. Microbiota can influence the expression of host microRNAs that, in turn, regulate the growth of intestinal bacteria by means of bidirectional host-gut micro-biota cross-talk. We investigated possible interactions among intestinal microbes and between them and host transcriptional modulators in autism. To this purpose, we analysed, by “omics” technologies, faecal microbiome, mycobiome and small non-coding-RNAs (particularly miRNAs and piRNAs) of children with autism and neurotypical development. Patients displayed gut dysbiosis, related to a reduction of healthy gut micro- and mycobiota, and up-regulated tran-scriptional modulators. The targets of dysregulated non-coding-RNAs are involved in intestinal permeability, inflammation and autism. Furthermore, microbial families, underrepresented in patients, participate to the production of human essential metabolites negatively influencing the health condition. Here, we propose a novel approach to analyse faeces as a whole and, for the first time, we detected miRNAs and piRNAs in faecal samples of patients with autism.
Project description:Alterations in gut microbiota have been implicated in the pathogenesis of Colorectal Cancer (CRC). Here we collected fecal samples from 14 CRC patients and 14 healthy volunteer cohorts, and characterized their microbiota using label-free quantitative metaproteomics method. We have quantified 30,062 gut microbial protein groups, 91,902 peptides, and 195 genera of microbes, among which 341 proteins were found significantly different in abundance between the CRC patients and healthy volunteers. Our study demonstrates that gut bacteria involve in CRC pathogenesis not only via taxonomy abundance variations but also functional activity changes.
Project description:Human saliva microbiota is phylogenetically divergent among host individuals yet their roles in health and disease are poorly appreciated. We employed a microbial functional gene microarray, HuMiChip 1.0, to reconstruct the global functional profiles of human saliva microbiota from ten healthy and ten caries-active adults. Saliva microbiota in the pilot population featured a vast diversity of functional genes. No significant distinction in gene number or diversity indices was observed between healthy and caries-active microbiota. However, co-presence network analysis of functional genes revealed that caries-active microbiota was more divergent in non-core genes than healthy microbiota, despite both groups exhibited a similar degree of conservation at their respective core genes. Furthermore, functional gene structure of saliva microbiota could potentially distinguish caries-active patients from healthy hosts. Microbial functions such as Diaminopimelate epimerase, Prephenate dehydrogenase, Pyruvate-formate lyase and N-acetylmuramoyl-L-alanine amidase were significantly linked to caries. Therefore, saliva microbiota carried disease-associated functional signatures, which could be potentially exploited for caries diagnosis. The DMFT INDEX (Decayed, Missing, Filled [DMF] teeth index used in dental epidemiology) values are provided for each sample We employed a microbial functional gene microarray, HuMiChip 1.0, to reconstruct the global functional profiles of human saliva microbiota from ten healthy and ten caries-active adults.
Project description:Morphine causes microbial dysbiosis. In this study we focused on restoration of native microbiota in morphine treated mice and looked at the extent of restoration and immunological consequences of this restoration. Fecal transplant has been successfully used clinically, especially for treating C. difficile infection2528. With our expanding knowledge of the central role of microbiome in maintenance of host immune homeostasis17, fecal transplant is gaining importance as a therapy for indications resulting from microbial dysbiosis. There is a major difference between fecal transplant being used for the treatment of C. difficile infection and the conditions described in our studies. The former strategy is based on the argument that microbial dysbiosis caused by disproportionate overgrowth of a pathobiont can be out-competed by re-introducing the missing flora by way of a normal microbiome transplant. This strategy is independent of host factors and systemic effects on the microbial composition. Here, we show that microbial dysbiosis caused due to morphine can be reversed by transplantation of microbiota from the placebo-treated animals.
Project description:Colorectal cancer (CRC) is closely related to gut dysbiosis. We investigated the effects of imbalanced gut microbiota on the progression of intestinal adenoma in Apcmin/+ mice model using fecal microbiota transplantation (FMT). Administration of feces from CRC patients increased tumor proliferation and decreased apoptosis in tumor cells. Abnormal expression of genes related to Wnt-protein binding and lipid metabolic process was observed.
Project description:Development of the gut microbiota is greatly impacted in preterm infants. Despite increasing knowledge about microbiota composition in preterm infants, knowledge about the functional signatures of the intestinal microbiota remains limited. The aim was to study transitions in microbiota activity during the first six postnatal weeks in ten preterm infants. A total of 64 stool samples were measured by LC-MS/MS.
Project description:Microbial dysbiosis is a colorectal cancer (CRC) hallmark and contributes to inflammation, tumor growth, and therapy response. Gut microbes signal via metabolites, but how the metabolites impact CRC is largely unknown. We interrogated fecal metabolites associated with mouse models of colon tumorigenesis with varying mutational load. We found that microbial metabolites from healthy mice or humans were growth-repressive, and this response was attenuated in mice and patients with CRC. Microbial profiling revealed that Lactobacillus reuteri and its metabolite, reuterin were downregulated in mouse and human CRC. Reuterin altered redox balance, and reduced survival, and proliferation in colon cancer cells. Reuterin induced selective protein oxidation, and inhibited ribosomal biogenesis and protein translation. Exogenous Lactobacillus reuteri restricted mouse colon tumor growth, increased tumor reactive oxygen species, and decreased protein translation in vivo. Our findings indicate that a healthy microbiome and specifically, Lactobacillus reuteri, is protective against CRC through microbial metabolite exchange.