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Healthcare (Basel, Switzerland) Sep 2022(), a bacterium that colonizes the gastrointestinal tract, is often isolated from periodontitis and abscesses as part of a complex bacterial infection. However, reports... (Review)
Review
(), a bacterium that colonizes the gastrointestinal tract, is often isolated from periodontitis and abscesses as part of a complex bacterial infection. However, reports of monobacterium infections due to are limited. Here, we report a case of monobacterial bacteremia caused by with the aim of identifying the source of the invasion and clarifying the clinical features. A 54-year-old patient presented with bacteremia due to and with an oral invasion that we suspected resulted from prior dental treatment. Using PubMed and Google Scholar databases, we undertook a systematic review of monobacteremia caused by . We identified 26 patients (mean age, 70.15 years) in our systematic review. bacteremia and its associated phenotypes were most frequently identified in spinal discitis, followed by epidural and lumbar abscesses, and infective endocarditis. The major risk factors were malignancy, diabetes mellitus, and post-arthroplasty. When is detected in blood cultures, evaluation and intervention for oral contamination may be indicated.
PubMed: 36141340
DOI: 10.3390/healthcare10091727 -
, an oral pathobiont associated with colorectal cancer, epigenetically reprograms human colonocytes.Gut Microbes Dec 2023Recently, an intestinal dysbiotic microbiota with enrichment in oral cavity bacteria has been described in colorectal cancer (CRC) patients. Here, we characterize and...
Recently, an intestinal dysbiotic microbiota with enrichment in oral cavity bacteria has been described in colorectal cancer (CRC) patients. Here, we characterize and investigate one of these oral pathobionts, the Gram-positive anaerobic coccus . We identified two phylotypes (A and B) exhibiting different phenotypes and adhesion capabilities. We observed a strong association of phylotype A with CRC, with its higher abundance in feces and in tumoral tissue compared with the normal homologous colonic mucosa, which was associated with a distinct methylation status of patients. By developing an hypoxic co-culture system of human primary colonic cells with anaerobic bacteria, we show that phylotype A alters the DNA methylation profile promoters of key tumor-suppressor genes, oncogenes, and genes involved in epithelial-mesenchymal transition. In colonic mucosa of CRC patients carrying phylotype A, we found similar DNA methylation alterations, together with significant enrichment of differentially expressed genes in pathways involved in inflammation, cell adhesion, and regulation of actin cytoskeleton, providing evidence of possible role in the carcinogenic process.
Topics: Humans; Gastrointestinal Microbiome; Firmicutes; Bacteria; Colorectal Neoplasms
PubMed: 37842920
DOI: 10.1080/19490976.2023.2265138 -
Anaerobe Oct 2021Parvimonas micra is an anaerobic, fastidious, gram positive organism commonly found in the oral cavity and gastrointestinal tract. It has been increasingly reported as... (Review)
Review
Parvimonas micra is an anaerobic, fastidious, gram positive organism commonly found in the oral cavity and gastrointestinal tract. It has been increasingly reported as the cause of septic arthritis of native joints, often times with delayed diagnosis leading to increased morbidity. Risk factors include immunosuppression, inflammation of the joint, and recent dental procedures or infections. It has been a historically difficult organism to culture. However, the development of and increasing use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has led to increased identification of P. micra. Common antibiotic susceptibilities, as well as data regarding susceptibilities in specific situations, have been reported, but susceptibility testing is required in all cases. Common treatments include clindamycin, penicillin, and metronidazole for six to ten weeks.
Topics: Animals; Anti-Bacterial Agents; Arthritis, Infectious; Firmicutes; Gram-Positive Bacterial Infections; Humans; Knee Joint
PubMed: 34217826
DOI: 10.1016/j.anaerobe.2021.102412 -
Oncogene Sep 2022Large-scale fecal shotgun metagenomic sequencing revealed the high abundance of Parvimonas micra in colorectal cancer (CRC) patients. We investigated the role and...
Large-scale fecal shotgun metagenomic sequencing revealed the high abundance of Parvimonas micra in colorectal cancer (CRC) patients. We investigated the role and clinical significance of P. micra in colorectal tumorigenesis. The abundance of P. micra was examined in 309 fecal samples and 165 colon biopsy tissues of CRC patients and healthy subjects. P. micra was significantly enriched in fecal samples from 128 CRC patients compared to 181 healthy subjects (P < 0.0001); and in colon tissue biopsies from 52 CRC patients compared to 61 healthy subjects (P < 0.0001). Multivariate analysis showed that P. micra is an independent risk factor of poor survival in CRC patients (Hazard Ratio: 1.93). P. micra strain was isolated from feces of a CRC patient. Apc mice gavaged with P. micra showed significantly higher tumor burden and tumor load (both P < 0.01). Consistently, gavage of P. micra significantly promoted colonocyte proliferation in conventional mice, which was further confirmed by germ-free mice. P. micra colonization up-regulated genes involved in cell proliferation, stemness, angiogenesis and invasiveness/metastasis; and enhanced Th17 cells infiltration and expression of Th17 cells-secreted cytokines (Il-17, Il-22, and Il-23) in the colon of Apc, conventional and germ-free mice. P. micra-conditioned medium significantly promoted the differentiation of CD4 T cells to Th17 cells (IL-17CD4 phenotype) and enhanced the oncogenic Wnt signaling pathway. In conclusion, P. micra promoted colorectal tumorigenesis in mice by inducing colonocyte proliferation and altering Th17 immune response. P. micra may act as a prognostic biomarker for poor survival of CRC patients.
Topics: Animals; Carcinogenesis; Cell Proliferation; Colorectal Neoplasms; Firmicutes; Gene Expression Regulation, Neoplastic; Humans; Interleukin-17; Mice
PubMed: 35882981
DOI: 10.1038/s41388-022-02395-7 -
Journal of Experimental & Clinical... Jan 2023Colorectal cancer (CRC) is the third most common cancer in the world, and a strong relationship exists between CRC and gut microbiota, which affects the occurrence,...
BACKGROUND
Colorectal cancer (CRC) is the third most common cancer in the world, and a strong relationship exists between CRC and gut microbiota, which affects the occurrence, development, and metastasis of cancer. Bioinformatics-based analyses revealed that the abundance of Parvimonas micra (P. micra) in the feces of patients with cancer is significantly higher than that in healthy people. Therefore, an important relationship may exist between P. micra and CRC.
METHODS
We first confirmed that P. micra can promote the proliferation of cell lines through cell experiments and mouse models. Then we selected the signaling pathways and content of exosomes to promote the development of CRC by transcriptomics and microRNA sequencing. Finally, we confirmed that P. micra promoted CRC development through miR-218-5p/Ras/ERK/c-Fos pathway through the in vivo and in vitro experiments.
RESULTS
First, it was confirmed by in vitro and in vivo experiments that P. micra can promote the development of CRC. Transcriptome analysis after the coincubation of bacteria and cells revealed that P. micra promoted cell proliferation by activating the Ras/ERK/c-Fos pathway. Furthermore, microRNA sequencing analysis of the cells and exosomes showed that miR-218-5p and protein tyrosine phosphatase receptor R (PTPRR) were the key factors involved in activating the Ras/ERK/c-Fos pathway, and the miR-218-5p inhibitor was used to confirm the role of microRNA in xenograft mice.
CONCLUSION
This experiment confirmed that P. micra promoted the development of CRC by upregulating miR-218-5p expression in cells and exosomes, inhibiting PTPRR expression, and ultimately activating the Ras/ERK/c-Fos signaling pathway.
Topics: Animals; Humans; Mice; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Gene Expression Regulation, Neoplastic; MicroRNAs; Signal Transduction; Firmicutes
PubMed: 36627634
DOI: 10.1186/s13046-022-02572-2 -
Enfermedades Infecciosas Y... Nov 2020
Topics: Endocarditis, Bacterial; Firmicutes; Humans
PubMed: 32098702
DOI: 10.1016/j.eimc.2020.01.012 -
Bioscience Reports Jun 2023The gut microbiota Parvimonas micra has been found to be enriched in gut mucosal tissues and fecal samples of colorectal cancer (CRC) patients compared with non-CRC...
The gut microbiota Parvimonas micra has been found to be enriched in gut mucosal tissues and fecal samples of colorectal cancer (CRC) patients compared with non-CRC controls. In the present study, we investigated the tumorigenic potential of P. micra and its regulatory pathways in CRC using HT-29, a low-grade CRC intestinal epithelial cell. For every P. micra-HT-29 interaction assay, HT-29 was co-cultured anaerobically with P. micra at an MOI of 100:1 (bacteria: cells) for 2 h. We found that P. micra increased HT-29 cell proliferation by 38.45% (P=0.008), with the highest wound healing rate at 24 h post-infection (P=0.02). In addition, inflammatory marker expression (IL-5, IL-8, CCL20, and CSF2) was also significantly induced. Shotgun proteomics profiling analysis revealed that P. micra affects the protein expression of HT-29 (157 up-regulated and 214 down-regulated proteins). Up-regulation of PSMB4 protein and its neighbouring subunits revealed association of the ubiquitin-proteasome pathway (UPP) in CRC carcinogenesis; whereas down-regulation of CUL1, YWHAH, and MCM3 signified cell cycle dysregulation. Moreover, 22 clinically relevant epithelial-mesenchymal transition (EMT)-markers were expressed in HT-29 infected with P. micra. Overall, the present study elucidated exacerbated oncogenic properties of P. micra in HT-29 via aberrant cell proliferation, enhanced wound healing, inflammation, up-regulation of UPPs, and activation of EMT pathways.
Topics: Humans; Colorectal Neoplasms; HT29 Cells; Cell Proliferation; Inflammation; Epithelial-Mesenchymal Transition; Cell Movement; Proteasome Endopeptidase Complex
PubMed: 37218575
DOI: 10.1042/BSR20230609 -
Cancer Immunology, Immunotherapy : CII Oct 2022The importance of the tumour microbiome in different aspects of colorectal cancer (CRC) has been increasingly recognised, but many questions remain. The aim of this...
The importance of the tumour microbiome in different aspects of colorectal cancer (CRC) has been increasingly recognised, but many questions remain. The aim of this study was to explore the effect of specific CRC associated microbes on the tumour immune response, which has a considerable prognostic value in CRC. We applied specific qPCR to detect Parvimonas micra and Fusobacterium nucleatum in tumour tissues from an immunologically well-characterised cohort of 69 CRC patients. This cohort included detailed analyses of immune profiles based on flow cytometry and transcriptomics in tumour tissue and blood, along with comprehensive analyses of molecular subtypes. P. micra and F. nucleatum were detected in 24% and 64% of tumour tissues, respectively. We found a significant association of P. micra with high-grade tumours and tumours of CMS1 subtype. F. nucleatum was significantly associated with right-sided tumours, microsatellite instability, and CMS1 tumours. The immunological analyses revealed significant associations of P. micra with activated CD69 T lymphocytes and increased antigen-presenting HLA-DR B lymphocytes. P. micra was also positively associated with M1 and M2 macrophage traits. The impact of P. micra tumour colonisation on the immune response was further assessed using transcriptomics in validation of our findings. No associations were found between F. nucleatum and immune profiles in this study. Our findings support novel associations between P. micra and the immune response in CRC. A better understanding of these interactions might help to identify important predictive and prognostic tools as well as new targets for therapy.
Topics: Colorectal Neoplasms; Firmicutes; Fusobacterium nucleatum; Humans; Microsatellite Instability
PubMed: 35301576
DOI: 10.1007/s00262-022-03179-4 -
Environmental Microbiology Reports Aug 2023Recent advances in our understanding of microbiome composition at sites of inflammatory dysbiosis have triggered a substantial interest in a variety of historically... (Review)
Review
Recent advances in our understanding of microbiome composition at sites of inflammatory dysbiosis have triggered a substantial interest in a variety of historically understudied bacteria, especially among fastidious obligate anaerobes. A plethora of new evidence suggests that these microbes play outsized roles in establishing synergistic polymicrobial infections at many different sites in the human body. Parvimonas micra is a prime example of such an organism. Despite being almost completely uncharacterized at the genetic level, it is one of the few species commonly detected in abundance at multiple mucosal sites experiencing either chronic or acute inflammatory diseases, and more recently, it has been proposed as a discriminating biomarker for multiple types of malignancies. In the absence of disease, P. micra is commonly found in low abundance, typically residing within the oral cavity and gastrointestinal tract. P. micra exhibits the typical features of an inflammophilic organism, meaning its growth actually benefits from active inflammation and inflammatory tissue destruction. In this mini-review, we will describe our current understanding of this underappreciated but ubiquitous pathobiont, specifically focusing upon the role of P. micra in polymicrobial inflammatory dysbiosis and cancer as well as the key emerging questions regarding its pathobiology. Through this timely work, we highlight Parvimonas micra as a significant driver of disease and discuss its unique position at the crossroads of dysbiosis and cancer.
Topics: Humans; Dysbiosis; Firmicutes; Neoplasms; Gastrointestinal Tract
PubMed: 36999244
DOI: 10.1111/1758-2229.13153 -
Respirology Case Reports Jun 2023commonly present in the oral cavity and intestinal tract of humans. indicating a high virulence, has the potential of forming abscess. The infection of may require...
commonly present in the oral cavity and intestinal tract of humans. indicating a high virulence, has the potential of forming abscess. The infection of may require surgical excision.
PubMed: 37206157
DOI: 10.1002/rcr2.1161