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Frontiers in Immunology 2020The intestinal microbiota, composed of a large population of microorganisms, is often considered a "forgotten organ" in human health and diseases. Increasing evidence... (Review)
Review
The intestinal microbiota, composed of a large population of microorganisms, is often considered a "forgotten organ" in human health and diseases. Increasing evidence indicates that dysbiosis of the intestinal microbiota is closely related to colorectal cancer (CRC). The roles for intestinal microorganisms that initiated and facilitated the CRC process are becoming increasingly clear. Hypothesis models have been proposed to illustrate the complex relationship between the intestinal microbiota and CRC. Recent studies have identified , enterotoxigenic , , , , and as CRC candidate pathogens. In this review, we summarized the mechanisms involved in microbiota-related colorectal carcinogenesis, including inflammation, pathogenic bacteria, and their virulence factors, genotoxins, oxidative stress, bacterial metabolites, and biofilm. We also described the clinical values of intestinal microbiota and novel strategies for preventing and treating CRC.
Topics: Adenocarcinoma; Animals; Bacteria; Biodiversity; Biofilms; Carcinogenesis; Cell Transformation, Neoplastic; Colorectal Neoplasms; Diet; Gastrointestinal Microbiome; Genes, APC; Humans; Inflammation; Mice; Models, Biological; Mutagens; Neoplastic Syndromes, Hereditary; Oxidative Stress; Rats; Virulence
PubMed: 33329610
DOI: 10.3389/fimmu.2020.615056 -
Microbiology Spectrum Dec 2022Streptococcus bovisStreptococcus equinus complex (SBSEC) is a common cause of infective endocarditis (IE). For IE-pathogens, the capacity to activate and aggregate...
Streptococcus bovisStreptococcus equinus complex (SBSEC) is a common cause of infective endocarditis (IE). For IE-pathogens, the capacity to activate and aggregate platelets is believed to be an important virulence mechanism. While the interactions between bacteria and platelets have been described in detail for many Gram-positive pathogens, little research has been carried out with SBSEC in this respect. Twenty-six isolates of the four most common species and subspecies of SBSEC identified in bacteremia were collected, and interactions with platelets were investigated in platelet rich plasma (PRP) from three donors. Aggregation was studied using light-transmission aggregometry and platelet activation using flow cytometry detecting surface upregulation of CD62P. Platelets and serum were treated with different inhibitors to determine mechanisms involved in platelet aggregation and activation. Twenty-two of 26 isolates induced aggregation in at least one donor, and four isolates induced aggregation in all three donors. In PRP from donor 1, isolate SL1 induced a rapid aggregation with a median time of 70 s to reach 50% aggregation. Blockade of the platelet Fc-receptor or enzymatic cleavage of IgG abolished platelet activation and aggregation. The capacity for bacteria-induced platelet aggregation was also shown to be transferable between donors through serum. SBSEC mediates platelet aggregation in an IgG and IgG-Fc-receptor dependent manner. Bacterial activation of platelets through this pathway is common for many bacteria causing IE and could be a potential therapeutic target for the prevention and treatment of this infection. The capacity of bacteria to activate and aggregate platelets is believed to contribute to the pathogenesis of IE. The Streptococcus bovis/Streptococcus equinus complex (SBSEC) contains known IE-pathogens, but there is limited research on the different subspecies ability to interact with platelets and what signaling pathways are involved. This study reports that 22 of 26 tested isolates of different subspecies within SBSEC can induce aggregation, and that aggregation is host dependent. The Fc-IgG-receptor pathway was shown essential for platelet activation and aggregation. To the best of our knowledge, this is the first study that reports on platelet interactions of SBSEC-isolates other than Streptococcus gallolyticus subspecies as well as the first study to report of mechanisms of platelet interaction of SBSEC-isolates. It adds SBSEC to a group of bacteria that activate and aggregate platelets via the platelet Fc-receptor. This could be a potential therapeutic target for prevention of IE.
Topics: Streptococcus bovis; Platelet Activation; Platelet Aggregation; Blood Platelets; Immunoglobulin G
PubMed: 36374116
DOI: 10.1128/spectrum.01861-22 -
Journal of Experimental & Clinical... Jan 2011Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S.... (Review)
Review
Streptococcus bovis (S. bovis) bacteria are associated with colorectal cancer and adenoma. S. bovis is currently named S. gallolyticus. 25 to 80% of patients with S. bovis/gallolyticus bacteremia have concomitant colorectal tumors. Colonic neoplasia may arise years after the presentation of bacteremia or infectious endocarditis of S. bovis/gallolyticus. The presence of S. bovis/gallolyticus bacteremia and/or endocarditis is also related to the presence of villous or tubular-villous adenomas in the large intestine. In addition, serological relationship of S. gallolyticus with colorectal tumors and direct colonization of S. gallolyticus in tissues of colorectal tumors were found. However, this association is still under controversy and has long been underestimated. Moreover, the etiological versus non-etiological nature of this associationis not settled yet. Therefore, by covering the most of up to date studies, this review attempts to clarify the nature and the core of S. bovis/gallolyicus association with colorectal tumors and analyze the possible underlying mechanisms.
Topics: Adenoma; Animals; Bacteremia; Colorectal Neoplasms; Endocarditis; Gastrointestinal Tract; Humans; Inflammation; Intestinal Mucosa; Precancerous Conditions; Streptococcal Infections; Streptococcus bovis
PubMed: 21247505
DOI: 10.1186/1756-9966-30-11 -
Enfermedades Infecciosas Y... Apr 2023Streptococcus bovis/equinus complex (SBEC) is a major cause of infective endocarditis (IE), although its incidence varies greatly depending on the geographical area. The...
INTRODUCTION
Streptococcus bovis/equinus complex (SBEC) is a major cause of infective endocarditis (IE), although its incidence varies greatly depending on the geographical area. The characteristics of IE caused by Streptococcus gallolyticus susp. gallolyticus are well known; there are hardly any descriptions of IE caused by other species or biotypes.
METHODS
Retrospective cohort study, from 1990 to 2019, of all SBEC IE in adults in three Spanish hospitals, Lugo (LH), Barcelona (BH) and Ferrol (FH) where the population is mainly rural, urban and mixed, respectively. The incidence of IE was analyzed in 3 areas. Clinical characteristics of IE (277 cases, 258 biotyped) were compared according to SBEC species and biotypes.
RESULTS
There are significant differences between the incidence of SBEC IE in HL (27.9/10) vs. HF and HB (8.8 and 7,1, respectively, p<0.001). We found significant differences (SbI vs. SbII) in mean age (68.5 vs. 73 years; p<0.01), duration of symptoms before diagnosis (46.9±46.5 vs. 30.4±40.9 days; p<0.01), presence of comorbidities: 39.1% (78) vs. 54.2% (32; p<0.04), predisposing heart illness:62.3% (124) vs. 81.3% (48; p<0.006), particularly, prosthetic or intravascular devices IE: 24.6% (49) vs. 52.4% (31; p<0.001), bi-valve involvement:23.6% (47) vs. 11.8% (7; p<0.05) and heart failure: 24.6% (49) vs. 38.9% (23; p<0.03). There were no significant differences in embolic events, need for surgery or mortality. The association with CRC was high in both groups: 77.7% vs. 66.6%.
CONCLUSIONS
IE due to SBEC has geographical variations in incidence and different clinical characteristics among biotypes. The association with CRC was high.
Topics: Adult; Humans; Streptococcus bovis; Retrospective Studies; Streptococcal Infections; Endocarditis, Bacterial; Endocarditis
PubMed: 36610830
DOI: 10.1016/j.eimce.2021.08.017 -
Cureus Apr 2022Cancer is an immunosuppressive disorder with characteristic features of unchecked cell growth, invasion, and sometimes thromboembolism leading to multiple systemic... (Review)
Review
Cancer is an immunosuppressive disorder with characteristic features of unchecked cell growth, invasion, and sometimes thromboembolism leading to multiple systemic sequelae, including infective endocarditis. This article has compiled some of the crucial mechanisms by which infective endocarditis occurs in cancer patients, its risk factors, and the existing treatment interventions. It has focused on the necessity of being aware that these multiple pathogeneses are involved in the development of infective endocarditis (IE) in cancer patients, which would help delineate the risk factors associated with the condition and help physicians screen better for specific red flags. Identifying these risk factors and patient-oriented therapy, targeting the necessary elements such as causative organism, patient immune status, type of cancer, choosing evidence-based treatment modalities, and to improve the outcome of the disease in an already exasperating condition called cancer.
PubMed: 35573527
DOI: 10.7759/cureus.24089 -
BMJ Case Reports Apr 2013Acute cholecystitis is a common inflammatory condition of the gallbladder caused most commonly by Escherichia coli, Enterococcus, and Klebsiella organisms. Streptococcus...
Acute cholecystitis is a common inflammatory condition of the gallbladder caused most commonly by Escherichia coli, Enterococcus, and Klebsiella organisms. Streptococcus bovis is a Gram-positive, catalase-negative, anaerobic coccus found as a commensal inhabitant of the digestive system in 16% of healthy people. We report a rare case of acute cholecystitis caused by S bovis and discuss its implications with regard to the two known S bovis biotypes (I & II) both of which are associated with a number of other gastrointestinal diseases.
Topics: Acute Disease; Anti-Bacterial Agents; Cholecystitis; Diagnosis, Differential; Diagnostic Imaging; Humans; Male; Middle Aged; Streptococcal Infections; Streptococcus bovis
PubMed: 23605823
DOI: 10.1136/bcr-2013-008581 -
International Journal of Molecular... Jan 2019/ complex (SBSEC), a non-enterococcal group D spp. complex, has been described as commensal bacteria in humans and animals, with a fecal carriage rate in humans varying... (Review)
Review
/ complex (SBSEC), a non-enterococcal group D spp. complex, has been described as commensal bacteria in humans and animals, with a fecal carriage rate in humans varying from 5% to over 60%. Among streptococci, SBSEC isolates represent the most antibiotic-resistant species-with variable resistance rates reported for clindamycin, erythromycin, tetracycline, and levofloxacin-and might act as a reservoir of multiple acquired genes. Moreover, reduced susceptibility to penicillin and vancomycin associated with mobile genetic elements have also been detected, although rarely. Since the association of SBSEC bacteremia and colon lesions, infective endocarditis and hepatobiliary diseases has been established, particularly in elderly individuals, an accurate identification of SBSEC isolates to the species and subspecies level, as well as the evaluation of antibiotic resistance, are needed. In this paper, we reviewed the major methods used to identify SBSEC isolates and the antimicrobial resistance rates reported in the scientific literature among SBSEC species.
Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Microbial; Gene Expression Regulation, Bacterial; Humans; Microbial Sensitivity Tests; Streptococcal Infections; Streptococcus; Streptococcus bovis
PubMed: 30678042
DOI: 10.3390/ijms20030480 -
Open Forum Infectious Diseases Nov 2023Invasive infection with complex (SBSEC) bacteria is associated with underlying colorectal neoplasia. However, the link between intestinal or fecal colonization with...
BACKGROUND
Invasive infection with complex (SBSEC) bacteria is associated with underlying colorectal neoplasia. However, the link between intestinal or fecal colonization with SBSEC isolates or antibody responses to SBSEC members and colorectal cancer is not thoroughly investigated in the literature.
METHODS
We searched the PubMed, EMBASE, and Web of Science databases for case-control studies as well as retrospective or prospective cohort studies reporting an association between SBSEC bacteria and colorectal neoplasia.
RESULTS
We identified 22 studies (15 case-control and 7 cohort) that met our inclusion criteria. Among the cohort studies, patients with SBSEC bacteremia were 3.73 times more likely to have underlying colorectal cancer compared with individuals with no bacteremia (relative risk [RR], 3.73; 95% CI, 2.79-5.01), whereas the risk of underlying colorectal adenoma in patients with SBSEC bacteremia was not significantly increased (RR, 5.00; 95% CI, 0.83-30.03). In case-control studies, patients with colorectal cancer were 2.27 times more likely to have evidence of intestinal or fecal colonization with SBSEC isolates (odds ratio [OR], 2.27; 95% CI, 1.11-4.62) and immunoglobulin G (IgG) antibody responses to SBSEC antigens (OR, 2.27; 95% CI, 1.06-4.86) compared with controls. Patients with colorectal adenoma were not more likely to be colonized with SBSEC isolates compared with controls (OR, 1.12; 95% CI, 0.55-2.25).
CONCLUSIONS
Apart from the well-established association of SBSEC bacteremia and underlying colorectal cancer, intestinal or fecal colonization with SBSEC isolates and IgG antibody responses to SBSEC antigens were higher in patients with colorectal cancer compared with controls. Neither bacteremia from SBSEC isolates nor colonization with SBSEC bacteria was associated with underlying colorectal adenoma.
PubMed: 38023558
DOI: 10.1093/ofid/ofad547 -
Journal of Clinical Microbiology Jul 2016The Streptococcus bovis group has undergone significant taxonomic changes over the past 2 decades with the advent of new identification methods with higher... (Review)
Review
The Streptococcus bovis group has undergone significant taxonomic changes over the past 2 decades with the advent of new identification methods with higher discriminatory power. Although the current classification system is not yet embraced by all researchers in the field and debate remains over the performance of molecular techniques for identification to the species level within the group, important disease associations for several members of the group have been clarified. Here, we provide a brief overview of the history of the S. bovis group, an outline of the currently accepted classification scheme, a review of associated clinical syndromes, and a summary of the performance and diagnostic accuracy of currently available identification methods.
Topics: Bacteriological Techniques; Humans; Molecular Diagnostic Techniques; Streptococcal Infections; Streptococcus bovis
PubMed: 26912760
DOI: 10.1128/JCM.02977-15 -
BMC Infectious Diseases Nov 2021Bacteremia due to the Streptococcus bovis/Streptococcus equinus complex (SBSEC) is associated with specific diseases, such as colorectal cancer and infective...
Laboratory identification and clinical characteristics of Streptococcus bovis/Streptococcus equinus complex bacteremia: a retrospective, multicenter study in Hiroshima, Japan.
BACKGROUND
Bacteremia due to the Streptococcus bovis/Streptococcus equinus complex (SBSEC) is associated with specific diseases, such as colorectal cancer and infective endocarditis. This study aimed to evaluate the clinical characteristics of SBSEC bacteremia and the accuracy of identification of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and phenotypic identification systems for SBSEC isolates.
METHODS
We analyzed patients with SBSEC bacteremia retrospectively between 2012 and 2019 at three hospitals in Japan. We re-identified each SBSEC isolate using sequencing superoxide dismutase (sodA) analysis, MALDI-TOF MS using the MALDI Biotyper, and phenotypic identification using the VITEK2.
RESULTS
During the study period, 39 patients with SBSEC bacteremia were identified. S. gallolyticus subsp. pasteurianus (SGSP, n = 29), S. gallolyticus subsp. gallolyticus (SGSG, n = 5), S. lutetiensis (SL, n = 4), and S. infantarius subsp. infantarius (n = 1) were identified using sodA sequencing analysis. Primary bacteremia (36%) was the most common cause of bacteremia, followed by infective endocarditis (26%) and biliary tract infections (23%). Colorectal cancer was associated significantly with SGSG bacteremia, while the sources of bacteremia were similar in each SBSEC subspecies. The MALDI Biotyper was significantly more accurate in identifying the SBSEC isolates at the subspecies level compared to the VITEK2 (92% vs. 67%, P = 0.010). In contrast, there were no significant differences in the rates of correct identification of the SBSEC isolates at the species level between the MALDI Biotyper and the VITEK2 (100% vs. 87%, P = 0.055).
CONCLUSIONS
Bacteremia with SGSG was associated with colorectal cancer, and the sources of bacteremia were similar in each SBSEC subspecies. The MALDI-TOF MS was significantly more accurate in identifying SBSEC isolates at the subspecies level than the phenotypic identification systems. The accurate identification of SBSEC isolates using the MALDI-TOF MS and phenotypic identification systems was sufficient at the species level, but it was insufficient at the subspecies level. Therefore, it may be reasonable for clinicians to perform echocardiographies and colonoscopies in all patients with SBSEC bacteremia.
Topics: Bacteremia; Humans; Japan; Laboratories; Retrospective Studies; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Streptococcal Infections; Streptococcus bovis
PubMed: 34836500
DOI: 10.1186/s12879-021-06880-4