Prognostic value of a combination of innovative factors (gut microbiota, sarcopenia, obesity, metabolic syndrome) to predict surgical/oncologic outcomes following surgery for sporadic colorectal cancer: a prospective cohort study protocol (METABIOTE)

Preclinical and clinical evidence of the association of colibactin-producing Escherichia coli with anxiety and depression in colon cancer

BACKGROUND

The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent. The gut microbiota contributes to colorectal carcinogenesis (CRC), as demonstrated with colibactin-producing Escherichia coli (CoPEC).

AIM

To evaluate the association between CoPEC prevalence and anxiety- and depressive-like behaviors with both preclinical and clinical approaches.

METHODS

Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric interview. Results were compared according to the CoPEC colonization. In parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC strain. Their behavior was assessed using the Elevated Plus Maze test, the Forced Swimming Test and the Behavior recognition system PhenoTyper^®.

RESULTS

In a limited cohort, all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis, whereas only one patient (17%) without CoPEC did. This result was confirmed in C57BL6/J wild-type mice and in a CRC susceptibility mouse model (adenomatous polyposis coli^{multiple intestinal neoplasia/+}). Mice exhibited a significant increase in anxiety- and depressive-like behaviors after chronic infection with a CoPEC strain.

CONCLUSION

This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

A systematic review of the association between parastomal hernia and sarcopenia

BACKGROUND

Sarcopenia is a multifactorial loss of muscle mass that can complicate surgical outcomes and increase morbidity and mortality. Parastomal hernias can occur after any surgery requiring stoma formation and is an area of concern as a complication as it can require a second surgery or emergency surgical intervention.

AIM

To assess the impact of sarcopenia on parastomal hernia formation in the postoperative period.

METHOD

A systematic search of publications using MEDLINE, CINAHL, and Cochrane databases was conducted in June 2022. Data were extracted, and a narrative synthesis was undertaken. The Crowe Critical Appraisal Tool (CCAT) assessed the quality of the included studies. The systematic review included original research studies, prospective and retrospective designs, and human studies written in English. Reviews, conference papers, opinion papers, and those including participants < 18 years old were excluded. No restrictions on the date of publication and study setting were applied.

RESULTS

Nine studies met the inclusion criteria, and these were conducted between 2016 and 2021; 56% (n = 5) used a retrospective study design. The mean sample size was 242.5 participants (SD = ±358.6). No consistent or standardized way of defining sarcopenia or measuring muscle mass was seen between the studies reviewed. However, 45% (n = 4) of the studies reported a significant relationship between sarcopenia and wound healing complications, including an increased incidence of parastomal and incisional hernias. The average CCAT score was 27.56 (SD = ±4.39).

CONCLUSION

There is no definitive relationship between sarcopenia and hernia development; however, four studies found a significant relationship between sarcopenia and hernia formation. It must also be considered that different disease processes can cause sarcopenia either through the disease process itself, or the treatment and management. More research and consistent measurements are needed before comparable and consistent outcomes can be compiled.

Dysbiosis and Gastrointestinal Surgery: Current Insights and Future Research

Surgery of the gastrointestinal tract can result in deep changes among the gut commensals in terms of abundance, function and health consequences. Elective colorectal surgery can occur for neoplastic or inflammatory bowel disease; in these settings, microbiota imbalance is described as a preoperative condition, and it is linked to post-operative complications, as well. The study of bariatric patients led to several insights into the role of gut microbiota in obesity and after major surgical injuries. Preoperative dysbiosis and post-surgical microbiota reassessment are still poorly understood, and they could become a key part of preventing post-surgical complications. In the current review, we outline the most recent literature regarding agents and molecular pathways involved in pre- and post-operative dysbiosis in patients undergoing gastrointestinal surgery. Defining the standard method for microbiota assessment in these patients could set up the future approach and clinical practice.

Relation of gut microbiota and postoperative gastrointestinal dysfunction in older patients with colon cancer undergoing elective colon resection: a protocol for a prospective, observational cohort study

INTRODUCTION

Gut microbiota (GM) appears critical for gastrointestinal symptoms, but whether alterations in GM are associated with increased risk of postoperative gastrointestinal dysfunction (POGID) in older patients with colon cancer (CC) undergoing elective colon resection remains unclear.

METHODS AND ANALYSIS

This study aims to prospectively recruit 284 elderly patients with CC undergoing elective colon resection. GM of fresh faeces specimens is characterised using 16S rRNA gene sequencing. Data are collected preoperatively, daily postoperatively during the in-hospital stay, and follow-up visits are scheduled four times within 30 days after discharge. Associations with POGID will be investigated using logistic regression models to calculate ORs with 95% CIs. The models include the adjustment for age, sex, frequency of spicy diet, coffee drinking and tea drinking, tobacco and alcohol history, diabetes, obesity, gastroenteritis, preoperative gut microbial composition. Furthermore, we will use joint modelling for longitudinal data to study several outcome variables simultaneously.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Board of West China Hospital, Sichuan University (IRB Number: 20201334). The results will be disseminated through peer-reviewed publications or conference presentations.

TRIAL REGISTRATION NUMBER

It has been registered in PROSPERO, number CRD42019145032. It has been registered in the Chinese clinical trial registry, number ChiCTR2100043646.

Changes in the gut bacterial communities in colon cancer surgery patients: an observational study

Background

Colon surgery has been shown to modulate the intestinal microbiota. Our objective was to characterize these changes using state-of-the-art next generation sequencing techniques.

Methods

We performed a single-centre prospective observational cohort study to evaluate the changes in the gut microbiota, i.e., taxon distribution, before and after elective oncologic colon surgery in adult patients with different antimicrobial prophylaxis regimens (standard prophylaxis with cefuroxime/metronidazole versus carbapenems for extended-spectrum beta-lactamase-producing Enterobacterales [ESBL-E] carriers). We obtained rectal samples on the day of surgery, intraoperative luminal samples, and rectal or stoma samples 3 days after surgery. We performed metataxonomic analysis based on sequencing of the bacterial 16S rRNA gene marker. Similarities and differences between bacterial communities were assessed using Bray–Curtis similarity, visualised using principal coordinates analysis and statistically tested by PERMANOVA. Comparison of taxa relative abundance was performed using ANCOM.

Results

We included 27 patients between March 27, 2019 and September 17, 2019. The median age was 63.6 years (IQR 56.4–76.3) and 44% were females. Most (81%) patients received standard perioperative prophylaxis as they were not ESBL carriers. There was no significant association between ESBL carriage and differences in gut microbiome. We observed large and significant increases in the genus Enterococcus between the preoperative/intraoperative samples and the postoperative sample, mainly driven by Enterococcus faecalis. There were significant differences in the postoperative microbiome between patients who received standard prophylaxis and carbapenems, specifically in the family Erysipelotrichaceae.

Conclusion

This hypothesis-generating study showed rapid changes in the rectal microbiota following colon cancer surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13099-021-00477-7.

Mapping the colorectal tumor microbiota

The gut microbiome in patients with colorectal cancer (CRC) is different than that of healthy controls. Previous studies have profiled the CRC tumor microbiome using a single biopsy. However, since the morphology and cellular subtype vary significantly within an individual tumor, the possibility of sampling error arises for the microbiome within an individual tumor. To test this hypothesis, seven biopsies were taken from representative areas on and off the tumor in five patients with CRC. The microbiome composition was strikingly similar across all samples from an individual. The variation in microbiome alpha-diversity was significantly greater between individuals' samples then within individuals. This is the first study, to our knowledge, that shows that the microbiome of an individual tumor is spatially homogeneous. Our finding strengthens the assumption that a single biopsy is representative of the entire tumor, and that microbiota changes are not limited to a specific area of the neoplasm.

Prevalence of Sarcopenia and Its Effect on Postoperative Complications in Patients with Crohn's Disease

Background and Aims

Sarcopenia is a prognostic factor of outcomes for various diseases, but reports on sarcopenia in patients with Crohn's disease (CD) are few. We aim to determine the prevalence of sarcopenia and assess the role of sarcopenia in postoperative complications in patients with CD at a tertiary referral center.

Methods

Patients who underwent intestinal surgery for CD from January 2013 to October 2019 were retrospectively enrolled. The L3 skeletal muscle mass index (SMI) was used to identify sarcopenia. Demographic data, preoperative laboratory data, surgical details, and hospital outcomes were recorded. The factors associated with postoperative complications were evaluated through univariate and multivariate analyses.

Results

One hundred and twenty-four patients were enrolled. Thirty-four of them (27.4%), including 11 males, were diagnosed with sarcopenia. Compared with patients without sarcopenia, sarcopenic patients had a significantly lower BMI (P < 0.001); lower preoperative serum albumin (P = 0.006), prealbumin (P = 0.030), and hemoglobin levels (P < 0.001); longer hospital stay (34.4 ± 26.8 days vs. 22.8 ± 15.6 days, P = 0.003); and more occurrences of complications (41.2% vs. 23.3%, P = 0.049). The overall incidence of postoperative complications was 28.2%. Infection (51.4%) and intestinal fistula (22.9%) were the most common among such complications. Through the multivariate analysis, sarcopenia was identified as an independent risk factor for major postoperative complications (odds ratio = 3.974, 95%CI = 1.171-13.489, P = 0.027).

Conclusion

Sarcopenia is common in patients with CD requiring bowel resection, and it significantly increases the risk of major postoperative complications.

Gut Microbiota as Potential Biomarker and/or Therapeutic Target to Improve the Management of Cancer: Focus on Colibactin-Producing Escherichia coli in Colorectal Cancer

Simple Summary

Gut microbiota is emerging as new diagnostic and prognostic marker and/or therapeutic target to improve the management of cancer. This review aims to summarize microbial signatures that have been associated with digestive and other cancers. We report the clinical relevance of these microbial markers to predict the response to cancer therapy. Among these biomarkers, colibactin-producing E. coli are prevalent in the colonic mucosa of patients with colorectal cancer and they promote colorectal carcinogenesis in several pre-clinical models. Here we discuss the promising use of colibactin-producing E. coli as a new predictive factor and a therapeutic target in colon cancer management.

Abstract

The gut microbiota is crucial for physiological development and immunological homeostasis. Alterations of this microbial community called dysbiosis, have been associated with cancers such colorectal cancers (CRC). The pro-carcinogenic potential of this dysbiotic microbiota has been demonstrated in the colon. Recently the role of the microbiota in the efficacy of anti-tumor therapeutic strategies has been described in digestive cancers and in other cancers (e.g., melanoma and sarcoma). Different bacterial species seem to be implicated in these mechanisms: F. nucleatum, B. fragilis, and colibactin-associated E. coli (CoPEC). CoPEC bacteria are prevalent in the colonic mucosa of patients with CRC and they promote colorectal carcinogenesis in susceptible mouse models of CRC. In this review, we report preclinical and clinical data that suggest that CoPEC could be a new factor predictive of poor outcomes that could be used to improve cancer management. Moreover, we describe the possibility of using these bacteria as new therapeutic targets.

Can the microbiota predict response to systemic cancer therapy, surgical outcomes, and survival? The answer is in the gut

INTRODUCTION

The gut microbiota seems to play a key role in tumorigenesis, across various hallmarks of cancer. Recent evidence suggests its potential use as a biomarker predicting drug response and adding prognostic information, generally in the context of immuno-oncology.

AREAS COVERED

In this review, we focus on the modulating effects of gut microbiota dysbiosis on various anticancer molecules used in practice, including cytotoxic and immune-modulating agents, primarily immune-checkpoint inhibitors (ICI). Pubmed/Medline-based literature search was conducted to find potential original studies that discuss gut microbiota as a prognostic and predictive biomarker for cancer therapy. We also looked at the US ClinicalTrials.gov website to find additional studies particularly ongoing human clinical trials.

EXPERT COMMENTARY

Sequencing of stool-derived materials and tissue samples from cancer patients and animal models has shown a significant enrichment of various bacteria such as Fusobacterium nucleatum and Bacteroides fragilis were associated with resistant disease and poorer outcomes. Gut microbiota was also found to be associated with surgical outcomes and seems to play a significant role in anastomotic leak (ATL) after surgery mainly by collagen breakdown. However, this research field is just at the beginning and the current findings are not yet ready to change clinical practice.