The Pathogenicity of Fusobacterium nucleatum Modulated by Dietary Fibers-A Possible Missing Link between the Dietary Composition and the Risk of Colorectal Cancer

Adherence to the Mediterranean diet and its protective effects against colorectal cancer: a meta-analysis of 26 studies with 2,217,404 participants

Colorectal cancer (CRC) is a major global health concern and represents a significant public health challenge in Hungary, where it exhibits some of the highest morbidity and mortality rates in the European Union. The Mediterranean diet has been suggested to reduce the incidence of CRC, but comprehensive evidence from diverse study designs is needed to substantiate this effect. A systematic literature search was conducted in PubMed, ClinicalTrials.gov, CENTRAL, and the Web of Science to identify randomized controlled trials and human clinical trials from 2008 to 2024 to identify relevant studies. Statistical analysis was performed using the https://metaanalysisonline.com web application using a random effects model to estimate the pooled hazard rates (HRs). Forest plots, funnel plots, and Z-score plots were utilized to visualize results. We identified 15 clinical trials and 9 case-control studies, encompassing a total of 2,217,404 subjects. The pooled analysis indicated that adherence to the Mediterranean diet significantly reduced the prevalence of CRC (HR = 0.84, 95% CI = 0.78-0.91, p < 0.01). This protective effect was consistent across sexes, with HRs of 0.85 (95% CI = 0.75-0.97, p = 0.01) for males and 0.88 (95% CI = 0.79-0.99, p = 0.03) for females. Case-control studies specifically showed a substantial effect (HR = 0.51, 95% CI = 0.38-0.68, p < 0.01). Notable heterogeneity was observed across studies, yet the a priori information size was substantially below the cumulative sample size, ensuring sufficient data for reliable conclusions. The findings from this meta-analysis reinforce the protective role of the Mediterranean diet against CRC. The results of this meta-analysis will inform dietary interventions designed to mitigate CRC risk, which are conducted within the framework of the Semmelweis Study, an ongoing comprehensive cohort study at Semmelweis University, designed to explore the multifaceted causes of unhealthy aging in Hungary. These interventions aim to explore the practical application of Mediterranean dietary patterns in reducing CRC incidence among the Hungarian population.

A Longitudinal Dynamic Change in LMR Can Be a Biomarker for Recurrence in Fusobacterium Nucleatum-Positive Colorectal Cancer Patients

Purpose

This study assessed lymphocyte-to-monocyte ratio (LMR) changes to predict postoperative recurrence in Fusobacterium nucleatum-positive (Fn-positive) CRC patients.

Patients and Methods

Clinical information and paraffin tissue specimens were collected from a retrospective cohort of 332 patients. The abundance of Fn in tumor tissue was measured using a quantitative polymerase chain reaction. We evaluated the prognostic value and diagnostic performance of the dynamic changes of LMR from pre-operative to post-treatment (pr-LMR-po) and the dynamic alterations of LMR from pre-operative to post-treatment to pre-end of follow-up (pr-LMR-f) in predicting recurrence in Fn-positive CRC.

Results

In the total cohort and adjuvant therapy group cohort, pr-LMR-po independently predicted recurrence-free survival in Fn-positive CRC patients. In the adjuvant therapy group, pr-LMR-po (High-High vs Low-Low: HR: 3.896, 95% CI: 1.503-10.095, p=0.005) was particularly significant. Meanwhile, pr-LMR-f can serve as a predictive biomarker for Fn-positive CRC recurrence, especially in the adjuvant therapy group cohort where the c-statistic for pr-LMR-f was 0.825 (95% CI: 0.804-0.8251), with a sensitivity of 83.6% and a specificity of 79.3%. Compared to the overall adjuvant therapy group cohort, the prognostic performance of pr-LMR-f was superior in the Fn-positive CRC adjuvant therapy group cohort (AUC: 0.825 VS 0.711). Finally, we constructed a prediction model combining pr-LMR-f and CEA. After internal validation using the bootstrap resampling, the model had an AUC of 0.9295, a sensitivity of 94%, and a specificity of 72.7% in the Fn-positive CRC adjuvant therapy group cohort.

Conclusion

This study found that pr-LMR-po predicts Fn-positive CRC prognosis, and pr-LMR-f may predict Fn-positive CRC recurrence.

Fusobacterium nucleatum Abundance is Associated with Cachexia in Colorectal Cancer Patients: The ColoCare Study

BACKGROUND

Cachexia accounts for about 20% of all cancer-related deaths and indicates poor prognosis. The impact of Fusobacterium nucleatum (Fn), a microbial risk factor for colorectal cancer (CRC), on the development of cachexia in CRC has not been established.

METHODS

We evaluated the association between Fn abundance in pre-surgical stool samples and onset of cachexia at 6 months post-surgery in n = 87 patients with stages I-III CRC in the ColoCare Study.

RESULTS

High fecal Fn abundance compared to negative/low fecal Fn abundance was associated with 4-fold increased risk of cachexia onset at 6 months post-surgery (OR = 4.82, 95% CI = 1.15, 20.10, p = 0.03).

CONCLUSION

Our findings suggest that high fecal Fn abundance was associated with an increased risk of cachexia at 6 months post-surgery in CRC patients. This is the first study to link Fn abundance with cachexia in CRC patients, offering novel insights into biological mechanisms and potential management of cancer cachexia. Due to the small sample size, our results should be interpreted with caution. Future studies with larger sample sizes are needed to validate these findings.

Antibiotic-induced dysbiosis in the SCIME™ recapitulates microbial community diversity and metabolites modulation of in vivo disease

Establishing the context

Intestinal dysbiosis is a significant concern among dog owners, and the gut health of pets is an emerging research field. In this context, the Simulator of the Canine Intestinal Microbial Ecosystem (SCIME™) was recently developed and validated with in vivo data.

Stating the purpose/introducing the study

The current study presents a further application of this model by using amoxicillin and clavulanic acid to induce dysbiosis, aiming to provoke changes in microbial community and metabolite production, which are well-known markers of the disease in vivo.

Describing methodology

Following the induction of dysbiosis, prebiotic supplementation was tested to investigate the potential for microbiota recovery under different dietary conditions.

Presenting the results

The results showed that antibiotic stimulation in the SCIME™ model can produce significant changes in microbial communities and metabolic activity, including a decrease in microbial richness, a reduction in propionic acid production, and alterations in microbial composition. Additionally, changes in ammonium and butyric acid levels induced by the tested diets were observed.

Discussing the findings

This alteration in microbial community and metabolites production mimicks in vivo canine dysbiosis patterns. A novel dynamic in vitro model simulating canine antibiotic-induced dysbiosis, capable of reproducing microbial and metabolic changes observed in vivo, has been developed and is suitable for testing the effects of nutritional changes.

Current advances in cancer energy metabolism under dietary restriction: a mini review

The manipulation of the energy or source of food for cancer cells has attracted significant attention in oncology research. Metabolic reprogramming of the immune system allows for a deeper understanding of cancer cell mechanisms, thereby impeding their progression. A more targeted approach is the restriction of cancer cells through dietary restriction (CR), which deprives cancer cells of the preferred energy sources within the tumor microenvironment, thereby enhancing immune cell efficacy. Although there is a plethora of CR strategies that can be employed to impede cancer progression, there is currently no comprehensive review that delineates the specific dietary restrictions that target the diverse metabolic pathways of cancer cells. This mini-review introduces amino acids as anti-cancer agents and discusses the role of dietary interventions in cancer prevention and treatment. It highlights the potential of a ketogenic diet as a therapeutic approach for cancer, elucidating its distinct mechanisms of action in tumor progression. Additionally, the potential of plant-based diets as anti-cancer agents and the role of polyphenols and vitamins in anti-cancer therapy were also discussed, along with some prospective interventions for CR as anti-tumor progression.

Fusobacterium nucleatum: An Overview of Evidence, Demi-Decadal Trends, and Its Role in Adverse Pregnancy Outcomes and Various Gynecological Diseases, including Cancers

Gynecological and obstetric infectious diseases are crucial to women's health. There is growing evidence that links the presence of Fusobacterium nucleatum (F. nucleatum), an anaerobic oral commensal and potential periodontal pathogen, to the development and progression of various human diseases, including cancers. While the role of this opportunistic oral pathogen has been extensively studied in colorectal cancer in recent years, research on its epidemiological evidence and mechanistic link to gynecological diseases (GDs) is still ongoing. Thus, the present review, which is the first of its kind, aims to undertake a comprehensive and critical reappraisal of F. nucleatum, including the genetics and mechanistic role in promoting adverse pregnancy outcomes (APOs) and various GDs, including cancers. Additionally, this review discusses new conceptual advances that link the immunomodulatory role of F. nucleatum to the development and progression of breast, ovarian, endometrial, and cervical carcinomas through the activation of various direct and indirect signaling pathways. However, further studies are needed to explore and elucidate the highly dynamic process of host-F. nucleatum interactions and discover new pathways, which will pave the way for the development of better preventive and therapeutic strategies against this pathobiont.

Promising dawn in tumor microenvironment therapy: engineering oral bacteria

Despite decades of research, cancer continues to be a major global health concern. The human mouth appears to be a multiplicity of local environments communicating with other organs and causing diseases via microbes. Nowadays, the role of oral microbes in the development and progression of cancer has received increasing scrutiny. At the same time, bioengineering technology and nanotechnology is growing rapidly, in which the physiological activities of natural bacteria are modified to improve the therapeutic efficiency of cancers. These engineered bacteria were transformed to achieve directed genetic reprogramming, selective functional reorganization and precise control. In contrast to endotoxins produced by typical genetically modified bacteria, oral flora exhibits favorable biosafety characteristics. To outline the current cognitions upon oral microbes, engineered microbes and human cancers, related literatures were searched and reviewed based on the PubMed database. We focused on a number of oral microbes and related mechanisms associated with the tumor microenvironment, which involve in cancer occurrence and development. Whether engineering oral bacteria can be a possible application of cancer therapy is worth consideration. A deeper understanding of the relationship between engineered oral bacteria and cancer therapy may enhance our knowledge of tumor pathogenesis thus providing new insights and strategies for cancer prevention and treatment.

Gut microbiome: decision-makers in the microenvironment of colorectal cancer

Colorectal cancer (CRC) is a common malignancy of the gastrointestinal tract, accounting for the second most common cause of gastrointestinal tumors. As one of the intestinal barriers, gut bacteria form biofilm, participate in intestinal work, and form the living environment of intestinal cells. Metagenomic next-generation sequencing (mNGS) of the gut bacteria in a large number of CRC patients has been established, enabling specific microbial signatures to be associated with colorectal adenomato-carcinoma. Gut bacteria are involved in both benign precursor lesions (polyps), in situ growth and metastasis of CRC. Therefore, the term tumorigenic bacteria was proposed in 2018, such as Escherichia coli, Fusobacterium nucleatum, enterotoxigenic Bacteroides fragilis, etc. Meanwhile, bacteria toxins (such as cytolethal distending toxin (CDT), Colibactin (Clb), B. fragilis toxin) affect the tumor microenvironment and promote cancer occurrence and tumor immune escape. It is important to note that there are differences in the bacteria of different types of CRC. In this paper, the role of tumorigenic bacteria in the polyp-cancer transformation and the effects of their secreted toxins on the tumor microenvironment will be discussed, thereby further exploring new ideas for the prevention and treatment of CRC.