Fusobacterium nucleatum promotes inflammatory and anti-apoptotic responses in colorectal cancer cells via ADP-heptose release and ALPK1/TIFA axis activation

Fusobacterium nucleatum modulates the Wnt/β-catenin pathway in colorectal cancer development

The Wnt/β-catenin signalling pathway normally maintains cellular and tissue homeostasis by regulating cellular differentiation and survival in a controlled manner. An aberrantly regulated Wnt/β-catenin signalling pathway can transform into an oncogenic pathway, which is associated with Colorectal cancer (CRC) as well as other cancers. CRC is one of the most frequently occurring gastrointestinal cancers worldwide. In CRC tissues, deregulation of Wnt/β-catenin pathway is observed, which indicates that this oncogenic pathway directly promotes CRC malignancy, cell migration, angiogenesis, chemoresistance, as well as shorter lifespan of a patient. Growing evidence suggests that human commensal microbes have a strong association with carcinogenesis, particularly the prevalence and high enrichment of Fusobacterium nucleatum in CRC progression. The Wnt/β-catenin pathway is one of the targeted pathways by F. nucleatum in CRC, where Fusobacterium adhesin attaches to E-cadherin to initiate infection. Also, Wnt/β-catenin pathway can be a potential target for the treatment of both CRC and F. nucleatum-positive CRC. Here, we discuss the underlying mechanisms of F. nucleatum-positive CRC development through modulation of Wnt/β-catenin signalling and its possibility for the application in targeted therapy of F. nucleatum-positive CRC.

Jiawei Ermiao Granules (JWEMGs) clear persistent HR-HPV infection though improving vaginal microecology

ETHNOPHARMACOLOGICAL RELEVANCE

Jiawei Ermiao Granules (JWEMGs), a traditional Chinese herbal formulation, has been widely used in China for the treatment of human papillomavirus (HPV) infections. However, the underlying mechanisms through which it exerts its antiviral effects remain poorly understood.

AIM OF THE STUDY

This study aimed to investigate the potential mechanisms by which JWEMGs modulate vaginal microecology and clear HPV infections, utilizing clinical trials, metagenomic sequencing, and in vitro models.

MATERIALS AND METHODS

Clinical indicators related to vaginal microecology, such as vaginal pH, cleanliness, Nugent score, Donders score, catalase, neuraminidase, and leukocyte esterase, were evaluated in 65 patients with high-risk HPV (HR-HPV) infection. The study examined the impact of two courses of oral JWEMGs on these clinical parameters. Additionally, metagenomic sequencing was performed on vaginal lavage samples from 33 patients to assess the alteration of the vaginal microbiome following JWEMGs treatment. Immunohistochemistry was used to detect ALPK1 expression in cervical exfoliated cells, and ELISA was employed to measure cytokine levels in vaginal lavage fluid. JWEMGs intervention was applied to HaCaT-HPV E6/E7 cells to evaluate its effects on restoring α-kinase 1 (ALPK1) expression and promoting the secretion of cytokines and chemokines.

RESULTS

Treatment with JWEMGs significantly improved several clinical indicators, including cleanliness, pH, Nugent score, Donders score, catalase, neuraminidase, and leukocyte esterase, in HR-HPV-infected patients. Furthermore, JWEMGs therapy led to an increased abundance of Lactobacillus species, especially Lactobacillus crispatus, and a marked reduction in Gardnerella species. JWEMGs treatment also significantly promoted ALPK1 expression in cervical exfoliated cells and augmented the secretion of key cytokines, including IL-6, IL-8, and TNF-α. In parallel, in vitro results showed that JWEMGs substantially enhanced IL-6, IL-8, TNF-α, CCL2, CCL5, and CCL7 secretion in HaCaT-HPV E6/E7 cells, which correlated with the activation of the ALPK1/NF-κB signaling pathway.

CONCLUSION

In conclusion, JWEMGs treatment effectively remodels the vaginal microbiota and bolsters mucosal immunity in the lower genital tract, thereby improving the vaginal microecology in HR-HPV-infected individuals. In vitro findings further demonstrated that JWEMGs promote cytokine and chemokine expression, activating the ALPK1/NF-κB pathway.

Detection of genetic determinants of potentially oncogenic representatives of the intestinal microbiota as biomarkers of colorectal cancer

Relevance. Colorectal cancer (CRC) is the second leading cause of cancer mortality worldwide. Non-invasive diagnostic methods based on the determination of hidden blood in the stool (fecal immunochemical test, guaiac test), which have been proven to be effective in clinical studies, are used for CRC screening. However, a significant disadvantage of the available non-invasive diagnostic methods is the low sensitivity in detecting the oncological process at the early stages. A number of recent studies discuss the relationship between the disease and various potentially oncogenic microorganisms in the human intestinal tract, which can be used to expand the arsenal of non-invasive methods for diagnosing CRC based on molecular genetic examination of a stool sample to identify oncogenic microorganisms. The aim of this study was to evaluate the possibility of using genetic determinants of potentially oncogenic microorganisms as markers for colorectal cancer, based on a comparison of their prevalence in groups of patients with colorectal cancer, facultative precancerous diseases and patients without intestinal pathology. Materials and methods. 215 participants were included in the "case–control" study: 70 patients with newly diagnosed colorectal cancer, 70 patients with inflammatory bowel disease, 75 participants without diagnosed intestinal pathology. Polymerase chain reaction (PCR) was used to identify and detect genes of potentially oncogenic microorganisms. Results and discussion. An association was found between CRC and the presence of the Bacteroides fragilis fragilisin gene (OR 7.00; 95% CI: 2.55–22.50; p 0.001), species-specific genes of the periodontal pathogenic microorganisms Fusobacterium nucleatum (OR 5.61; 95% CI: 2.87–11.30; p 0.001) and Porphyromonas gingivalis (OR 16.3; 95% CI: 4.33–106.00; p 0.001), the clbB gene of pks pathogenicity island of the Enterobacteria (OR 3.44; 95% CI: 1.39–8.51; p = 0.010). Conclusion. The presence of genetic markers of potentially oncogenic bacterial species and genotypes in the gut microbiome is associated with colorectal cancer. The results obtained support the possibility of using molecular genetic detection of the studied potentially oncogenic microorganisms as a method for non-invasive diagnosis of CRC.

Fusobacterium nucleatum promotes PD-L1 expression in cancer cells to evade CD8+ T cell killing in breast cancer

BACKGROUND

A significant percentage of cancer-related fatalities are caused by breast cancer (BC). Fusobacterium nucleatum (Fn) is a common Gram-negative anaerobic bacterium found in various inflammatory diseases, and there are also reports suggesting its involvement in cancer progression. This study discussed molecular mechanisms of Fn-induced immune escape in BC cells.

METHODS

mRNA and protein PD-L1 expression in BC cells were detected using qRT-PCR and western blot (WB). WB assayed NF-κB-related marker expressions (p-p65, p-65, p-p50, p-50) in cells. PD-L1 expression levels on the cell surface, apoptosis and proliferation of CD8+ T and BC cells were measured via flow cytometry. ELISA tested TNFα, IFNγ, and granzyme B to assess the activation level of CD8+ T cells. The secretion level of LDH in the co-culture system was tested using an LDH detection kit to evaluate the cell death rate.

RESULTS

BC cells stimulated by Fn can blunt tumor-killing of CD8+ T cells and their vitality. Fn treatment upregulates PD-L1 in BC cells. Rescue experiments using NF-κB inhibitors suggested that Fn treatment mediated NF-κB signaling and fostered PD-L1 expression in cancer cells. Fn repressed the killing effect of CD8+ T cells on BC cells by triggering the NF-κB/PD-L1 signaling pathway.

CONCLUSION

Fn helps BC cells evade the killing effect of CD8+ T cells through the NF-κB/PD-L1 pathway.

TIFA enhances glycolysis through E2F1 and promotes the progression of glioma

OBJECTIVE

TRAF interacting protein with forkhead associated domain (TIFA) influence progression of many cancers. However, its role in glioma remains to be explored. This study investigated the function of TIFA in glioma.

METHODS

The TIFA expression in glioma and patient outcomes were analyzed using online database. Gene set enrichment analysis (GSEA) revealed related mechanisms of TIFA in glioma. TIFA's effects on glioma glycolysis and growth were assessed using in vitro and in vivo experiments. Moreover, luciferase reporter and ChIP were employed to explore the interactions among E2F1, GLUT1, HK2, and LDHA. The subcutaneous xenograft assay further elaborated the effects of TIFA in glioma.

RESULTS

We found overexpressed TIFA in glioma. Moreover, the high TIFA expression was associated with poor prognosis of glioma. Furthermore, GSEA indicated that overexpressed TIFA promoted E2F1 and glycolysis. Knockdown of TIFA decreased glioma development in cell and mice. TIFA knockdown down-regulated the expression of E2F1, GLUT1, HK2, and LDHA.

CONCLUSIONS

The study provides evidence that TIFA regulates E2F1 expression in glioma cells and promotes the proliferation, migration, and glycolysis. TIFA might be an advantageous therapeutic strategy against glioma.

From colon wall to tumor niche: Unraveling the microbiome's role in colorectal cancer progression

Colorectal cancer (CRC) is influenced by perturbations in the colonic microbiota, characterized by an imbalance favoring pathogenic bacteria over beneficial ones. This dysbiosis contributes to CRC initiation and progression through mechanisms such as carcinogenic metabolite production, inflammation induction, DNA damage, and oncogenic signaling activation. Understanding the role of external factors in shaping the colonic microbiota is crucial for mitigating CRC progression. This study aims to elucidate the gut microbiome's role in CRC progression by analyzing paired tumor and mucosal tissue samples obtained from the colon walls of 17 patients. Through sequencing of the V3-V4 region of the 16S rRNA gene, we characterized the tumor microbiome and assessed its association with clinical variables. Our findings revealed a significant reduction in alpha diversity within tumor samples compared to paired colon biopsy samples, indicating a less diverse microbial environment within the tumor microenvironment. While both tissues exhibited dominance of similar bacterial phyla, their relative abundances varied, suggesting potential colon-specific effects. Fusobacteriota enrichment, notably in the right colon, may be linked to MLH1 deficiency. Taxonomy analysis identified diverse bacterial genera, with some primarily associated with the colon wall and others unique to this region. Conversely, several genera were exclusively expressed in tumor tissue. Functional biomarker analysis identified three key genes with differential abundance between tumor microenvironment and colon tissue, indicating distinct metabolic activities. Functional biomarker analysis revealed three key genes with differential abundance: K11076 (putrescine transport system) and K10535 (nitrification) were enriched in the tumor microenvironment, while K11329 (SasA-RpaAB circadian timing mediator) dominated colon tissue. Metabolic pathway analysis linked seven metabolic pathways to the microbiome. Collectively, these findings highlight significant gut microbiome alterations in CRC and strongly suggest that long-term dysbiosis profoundly impacts CRC progression.

Leucine restriction ameliorates Fusobacterium nucleatum-driven malignant progression and radioresistance in nasopharyngeal carcinoma

Radiotherapy resistance is the main cause of treatment failure among patients with nasopharyngeal carcinoma (NPC). Recently, increasing evidence has linked the presence of intratumoral Fusobacterium nucleatum (Fn) with the malignant progression and therapeutic resistance of multiple tumor types, but its influence on NPC has remained largely unknown. We found that Fn is prevalent in the tumor tissue of patients with NPC and is associated with radioresistance. Fn invaded and proliferated inside NPC cells and aggravated tumor progression. Mechanistically, Fn slowed mitochondrial dysfunction by promoting mitochondrial fusion and decreasing ROS generation, preventing radiation-induced oxidative damage. Fn inhibited PANoptosis by the SLC7A5/leucine-mTORC1 axis during irradiation stress, thus promoting radioresistance. Treatment with the mitochondria-targeted antibiotics or dietary restriction of leucine reduced intratumoral Fn load, resensitizing tumors to radiotherapy in vivo. These findings demonstrate that Fn has the potential to be a predictive marker for radioresistance and to help guide individualized treatment for patients with NPC.

Antioxidant Role of Probiotics in Inflammation-Induced Colorectal Cancer

Colorectal cancer (CRC) continues to be a significant contributor to global morbidity and mortality. Emerging evidence indicates that disturbances in gut microbial composition, the formation of reactive oxygen species (ROS), and the resulting inflammation can lead to DNA damage, driving the pathogenesis and progression of CRC. Notably, bacterial metabolites can either protect against or contribute to oxidative stress by modulating the activity of antioxidant enzymes and influencing signaling pathways that govern ROS-induced inflammation. Additionally, microbiota byproducts, when supplemented through probiotics, can affect tumor microenvironments to enhance treatment efficacy and selectively mediate the ROS-induced destruction of CRC cells. This review aims to discuss the mechanisms by which taxonomical shifts in gut microbiota and related metabolites such as short-chain fatty acids, secondary bile acids, and trimethylamine-N-oxide influence ROS concentrations to safeguard or promote the onset of inflammation-mediated CRC. Additionally, we focus on the role of probiotic species in modulating ROS-mediated signaling pathways that influence both oxidative status and inflammation, such as Nrf2-Keap1, NF-κB, and NLRP3 to mitigate carcinogenesis. Overall, a deeper understanding of the role of gut microbiota on oxidative stress may aid in delaying or preventing the onset of CRC and offer new avenues for adjunct, CRC-specific therapeutic interventions such as cancer immunotherapy.

The oral-gut microbiome axis in inflammatory bowel disease: from inside to insight

Inflammatory bowel disease (IBD) is an idiopathic and persistent inflammatory illness of the bowels, leading to a substantial burden on both society and patients due to its high incidence and recurrence. The pathogenesis of IBD is multifaceted, partly attributed to the imbalance of immune responses toward the gut microbiota. There is a correlation between the severity of the disease and the imbalance in the oral microbiota, which has been discovered in recent research highlighting the role of oral microbes in the development of IBD. In addition, various oral conditions, such as angular cheilitis and periodontitis, are common extraintestinal manifestations (EIMs) of IBD and are associated with the severity of colonic inflammation. However, it is still unclear exactly how the oral microbiota contributes to the pathogenesis of IBD. This review sheds light on the probable causal involvement of oral microbiota in intestinal inflammation by providing an overview of the evidence, developments, and future directions regarding the relationship between oral microbiota and IBD. Changes in the oral microbiota can serve as markers for IBD, aiding in early diagnosis and predicting disease progression. Promising advances in probiotic-mediated oral microbiome modification and antibiotic-targeted eradication of specific oral pathogens hold potential to prevent IBD recurrence.

The interactions between traditional Chinese medicine and gut microbiota in cancers: Current status and future perspectives

The gut microbiota, known as the "forgotten organ" and "human second genome," comprises a complex microecosystem. It significantly influences the development of various tumors, including colorectal, liver, stomach, breast, and lung cancers, through both direct and indirect mechanisms. These mechanisms include the "gut-liver" axis, the "lung-intestine" axis, and interactions with the immune system. The intestinal flora exhibits dual roles in cancer, both promoting and suppressing its progression. Traditional Chinese medicine (TCM) can alter cancer progression by regulating the intestinal flora. It modifies the intestinal flora's composition and structure, along with the levels of endogenous metabolites, thus affecting the intestinal barrier, immune system, and overall body metabolism. These actions contribute to TCM's significant antitumor effects. Moreover, the gut microbiota metabolizes TCM components, enhancing their antitumor properties. Therefore, exploring the interaction between TCM and the intestinal flora offers a novel perspective in understanding TCM's antitumor mechanisms. This paper succinctly reviews the association between gut flora and the development of tumors, including colorectal, liver, gastric, breast, and lung cancers. It further examines current research on the interaction between TCM and intestinal flora, with a focus on its antitumor efficacy. It identifies limitations in existing studies and suggests recommendations, providing insights into antitumor drug research and exploring TCM's antitumor effectiveness. Additionally, this paper aims to guide future research on TCM and the gut microbiota in antitumor studies.