Prevalence of pks + bacteria and enterotoxigenic Bacteroides fragilis in patients with colorectal cancer (original) (raw)
Related papers
PLOS ONE
Escherichia coli (E. coli) from the B2 phylogenetic group is implicated in colorectal cancer (CRC) as it possesses a genomic island, termed polyketide synthetase (pks), which codes for the synthesis of colibactin, a genotoxin that induces DNA damage, cell cycle arrest, mutations and chromosomal instability in eukaryotic cells. The aim of this study was to detect and compare the prevalence of E. coli expressing pks (pks + E. coli) in CRC patients and healthy controls followed by investigating the virulence triggered by pks + E. coli using an in-vitro model. Mucosal colon tissues were collected and processed to determine the presence of pks + E. coli. Thereafter, primary colon epithelial (PCE) and colorectal carcinoma (HCT116) cell lines were used to detect cytopathic response to the isolated pks + E. coli strains. Our results showed 16.7% and 4.3% of CRC and healthy controls, respectively were pks + E. coli. Further, PCE displayed syncytia and cell swelling and HCT116 cells, megalocytosis, in response to treatment with the isolated pks + E. coli strains. In conclusion, pks + E. coli was more often isolated from tissue of CRC patients compared to healthy individuals, and our in-vitro assays suggest these isolated strains may be involved in the initiation and development of CRC.
pks+ Escherichia coli more prevalent in benign than malignant colorectal tumors
Molecular Biology Reports, 2021
Background: Some E. coli strains that synthesize the toxin colibactin within the 54-kb pks island are being implicated in colorectal cancer (CRC) development. Here, the prevalence of pks + E. coli in malignant and benign colorectal tumors obtained from selected Filipino patients was compared to determine the association of pks + E. coli with CRC in this population. Methods and Results: A realtime qPCR protocol was developed to quantify uidA, clbB, clbN, and clbA genes in formalin fixed paraffin embedded colorectal tissues. The number of malignant tumors (44/62; 71%) positive for the uidA gene was not significantly different (p=0.3428) from benign (38/62; 61%) tumors. Significantly higher number of benign samples (p<0.05) were positive for all three colibactin genes (clbB, clbN, and clbA) compared with malignant samples. There was also higher prevalence of pks + E. coli among older females and in tissue samples taken from the rectum. Conclusion: Hence, pks + E. coli may not be associated with CRC development among Filipinos.
Association of oncogenic bacteria with colorectal cancer in South China
Oncotarget, 2016
To quantify Fusobacterium spp., Enterococcus faecalis (E.faecalis), Enterotoxigenic Bacteroides fragilis (ETBF), and Enteropathogenic Escherichia coli in colorectal cancer (CRC) patients and their possible association with CRC clinicopathogical features, we collected the resected tumors and adjacent normal tissues (N) from 97 CRC patients. 48 age-and sex-matched healthy controls (HC) were also recruited. Real-time PCR was used for bacterial quantification. The median abundance of Fusobacterium spp. (p < 0.001, vs. N; p < 0.01,vs. HC), E.faecalis (p < 0.05, vs. N; p < 0.01, vs. HC) and ETBF (p < 0.001, vs. N; p < 0.05,vs. HC) in tumor tissues was significantly higher than that detected in normal tissue and HC. E.faecalis was detected in 95.88% of tumors and 93.81% of adjacent tissues. Fusobacterium spp. was detected in 72.16% of tumors and 67.01% of adjacent tissues. The combined E.faecalis and Fusobacterium spp. were detected in 70.10% of tumors and 36.08% of adjacent normal tissues. All four bacteria were detected in 33.72% and 22.09% of paired tumor and adjacent normal tissues, respectively. E.faecalis and Fusobacterium spp. are enriched in both tumor and adjacent tissue of CRC patients when compared to HC, suggesting that it is possible to be previously undetected changes in the pathohistologically normal colon tissue in the proximity of the tumor.
Most Frequent Bacteria in Colorectal Cancer Patients and Their Roles in Colorectal Carcinogenesis
2020
NK: Natural Killer; NKT: Natural Killer T; IL: Interleukin; CD: Cluster of Differentiation; TH: T Helper: TLR4: Toll Like Receptor-4; Cox: Cyclooxygenase; PGE: Prostaglandin E; EGFR: Epidermal Growth Factor Receptor; STAT3: Signal Transducer and Activator of Transcription-3; APC: Adenomatous Poly Colorectal cancer is the third most common cancer worldwide. The intestinal mucosal surface is continuously exposed to enormous microorganisms. The human intestinal tract harbors approximately 1014 bacteria. Most of these bacteria have roles in intestinal homeostasis and may exert anticancer effects. However, bacterial metabolites that are genotoxic can trigger epithelial cell carcinogenesis. Furthermore, a variety of inflammatory mediators produced during bacterial infection can also promote cancer development and progression. Some bacterial species are associated with human colorectal cancer. These bacteria can be involved in colorectal cancer development and progression through induction...
Microbiome distinctions between the CRC carcinogenic pathways
Gut Microbes
Colorectal cancer (CRC) is the third most commonly diagnosed cancer, the third leading cause of cancer-related deaths, and has been on the rise among young adults in the United States. Research has established that the colonic microbiome is different in patients with CRC compared to healthy controls, but few studies have investigated if and how the microbiome may relate to CRC progression through the serrated pathway versus the adenoma-carcinoma sequence. Our view is that progress in CRC microbiome research requires consideration of how the microbiome may contribute to CRC carcinogenesis through the distinct pathways that lead to CRC, which could enable the creation of novel and tailored prevention, screening, and therapeutic interventions. We first highlight the limitations in existing CRC microbiome research and offer corresponding solutions for investigating the microbiome's role in the adenoma-carcinoma sequence and serrated pathway. We then summarize the findings in the select human studies that included data points related to the two major carcinogenic pathways. These studies investigate the microbiome in CRC carcinogenesis and 1) utilize mucosal samples and 2) compare polyps or tumors by histopathologic type, molecular/genetic type, or location in the colon. Key findings from these studies include: 1) Fusobacterium is associated with right-sided, more advanced, and serrated lesions; 2) the colons of people with CRC have bacteria typically associated with normal oral flora; and 3) colons from people with CRC have more biofilms, and these biofilms are predominantly located in the proximal colon (single study).
Cancers, 2021
Simple Summary In colorectal cancer patients, epithelial barrier dysfunction can lead to increased intestinal permeability, and gut microbiome was found to vary compared to healthy subjects. We conducted a study to investigate whether bacterial translocation from gastrointestinal tract to bloodstream is associated to intestinal adenoma and/or colorectal cancer. In particular, an epidemiological and metagenomic approach was used to evaluate the relation of the bacterial DNA load and the bacterial taxonomic groups—assessed by 16S rRNA profiling—in blood with the risks of intestinal adenoma and colorectal cancer. These findings can confirm the presence of bacterial DNA in blood in healthy adults and serve as a basis to evaluate new non-invasive techniques for an early CRC diagnosis through the analyses of bacterial DNA circulating in peripheral blood. Abstract Inflammation and immunity are linked to intestinal adenoma (IA) and colorectal cancer (CRC) development. The gut microbiota is ...
Enfermedades Infecciosas y Microbiología Clínica, 2004
Understanding the pathogenesis of recurrent urinary tract infection (RUTI) and whether it is attributable to reinfection with a new strain or relapse with the primary infecting strain is of considerable importance. Because previous studies regarding community-acquired Klebsiella pneumoniae RUTI are inconclusive, we undertook this study to evaluate the characteristics of the host and the bacterial agent K. pneumoniae in RUTI. A prospective study was designed, using consecutive patients diagnosed with community-acquired K. pneumoniae-related UTI from January 2007 to December 2009. Of the total 468 consecutive episodes, we found 7 patients with RUTI. All the patients with RUTI were elderly (median, 74 years), with diabetes (100 %, 7 out of 7). Clinical K. pneumoniae isolates derived from the same patients with RUTI revealed identical genomic fingerprints, indicating that K. pneumoniae UTI relapsed despite appropriate antibiotic therapy. The antimicrobial resistance, growth curve and biofilm formation of the recurrent isolates did not change. K. pneumoniae strains causing RUTI had more adhesion and invasiveness than the colonization strains (p<0.01). When we compared the recurrent strains with the community-acquired UTI strains, the prevalence of diabetes mellitus was significant (100 % vs 53.7 %, p=0.03) in the RUTI group. Our data suggest that K. pneumoniae strains might be able to persist within the urinary tract despite appropriate antibiotic treatment, and the greater adhesion and invasiveness in the recurrent strains may play an important role in recurrent infections.
Acute bacterial infection negatively impacts cancer specific survival of colorectal cancer patients
World Journal of Gastroenterology, 2014
AIM: To assess the impact of bacterial infections on cancer-specific survival in patients with colorectal cancer. METHODS: This was a retrospective cohort study of colorectal cancer patients treated at the A.C. Camargo Cancer Center between January 2006 and April 2010. The presence of bacterial infection during cancer treatment, or up to one year after, was confirmed by laboratory tests or by the physician. Infections of the urinary, respiratory or digestive tracts, bloodstream, skin or surgical site were defined by testing within a single laboratory. Criteria for exclusion from the study were: chronically immunosuppressed patients; transplant patients (due to chronic immunosuppression); human immunodeficiency virus carriers; chronic use of corticosteroids or other immunosuppressive drugs; patients with autoimmune disease or primary immunodeficiency; known viral or parasitic infections. Patients with infections that did not require hospitalization were not included in the study because of the difficulty of collecting and tracking data related to infectious processes. In addition, patients hospitalized for pulmonary thromboembolism, stroke, acute myocardial infarction, uncontrolled diabetes, malignant hypercalcemia or other serious non-infectious complications not directly related to infection were also excluded. Survival curves were plotted using the Kaplan-Meier method, and logrank tests (univariate analysis) and a Cox test assuming a proportional hazards model (multivariate analysis) were performed to examine associations between clinical history and characteristics of infection with cancer-specific survival. RESULTS: One-hundred and six patients with colorectal cancer were divided into two groups based on the presence or absence of bacterial infection. Patient ages ranged from 23 to 91 years, with a median of 55 years. The majority of patients were male (57/106, 53.77%) with stage Ⅲ colorectal cancer (45/106, 44.11%). A total of 86 bacteriologic events were recorded. Results indicate that the presence and number of infections during or after the end of treatment were associated with poorer-cancer specific survivals (P = 0.02). Elevated neutrophil counts were also associated with poorer cancer-specific survival (P = 0.02). Analysis of patient age revealed that patients > 65 years of age had a poorer cancer-specific survival (P = 0.04). A multivariate analysis demonstrated that infection was an independent predictor of poor survival (HR = 2.62, 95%CI: 1.26-5.45; P = 0.01) along with advanced clinical staging (HR = 2.63, 95%CI: 1.08-6.39; P = 0.03). CONCLUSION: Infection and high neutrophil counts are associated with a poorer cancer-specific survival in colorectal cancer patients.
Association Between Bacteremia from Specific Microbes and Subsequent Diagnosis of Colorectal Cancer
Gastroenterology, 2018
Colorectal cancer (CRC) development has been associated with increased proportions of Bacteroides fragilis and certain Streptococcus, Fusobacterium, and Peptostreptococcus species in the intestinal microbiota. We investigated associations between bacteremia from specific intestinal microbes and occurrence of CRC. We performed a retrospective study, collecting data from13,096 adult patients (exposed group) in Hong Kong hospitalized with bacteremia (identified by blood culture test), without a previous diagnosis of cancer, from January 1, 2006 through December 31, 2015. We collected data on intestinal microbes previously associated with CRC (genera Bacteroides, Clostridium, Filifactor, Fusobacterium, Gemella, Granulicatella, Parvimonas, Peptostreptococcus, Prevotella, Solobacterium, and Streptococcus). Clinical information including patient demographics, comorbid medical conditions, date of bacteremia, and the bacterial species identified were collected. The incidence of biopsy-proven...