Recombinant Bifidobacterium longum Carrying Endostatin Protein Alleviates Dextran Sodium Sulfate-Induced Colitis and Colon Cancer in Rats

Chinese yam polysaccharide enhances anti-PD-1 immunotherapy in colorectal cancer through alterations in the gut microbiota and metabolites

Immune checkpoint inhibitors (ICIs) have shown limited efficacy in colorectal cancer (CRC). Chinese yam polysaccharide (CYP), a naturally derived plant polysaccharide, demonstrates immunomodulatory and antitumour activities. This study investigated whether CYP enhances the antitumour effects of αPD-1 monoclonal antibody (mAb) by modulating gut microbiota and metabolites. In MC38 and CT26 xenograft models, CYP synergistically inhibited tumour growth when combined with αPD-1 mAb. 16S rRNA sequencing revealed that the combination therapy enriched beneficial bacteria (such as Clostridia_UCG-014 and Actinobacteria) while reducing pathogenic bacteria (including Enterorhabdus and Desulfovibrionaceae). Antibiotic-mediated gut microbiota ablation abolished therapeutic benefits, confirming microbiota-dependent mechanisms. Cytometry by Time-Of-Flight indicated that the combination therapy reshaped the tumour microenvironment by inhibiting immunosuppressive M2 macrophages (CD206+ subset) and enhancing infiltration of cytotoxic CD8+ T cells. Metabolomics analysis demonstrated that the combination therapy effectively rectified tumour-induced metabolic dysregulation, particularly in pathways related to linoleic acid, tryptophan, and purine metabolism. Significantly, the purine-associated metabolite deoxyguanosine was identified to promote M2 macrophage polarization and tumour progression in vitro, whereas its levels were markedly attenuated following combined therapeutic intervention. The results suggest that CYP enhances the efficacy of αPD-1 mAb through remodeling gut microbiota, reducing pro-tumour metabolite (deoxyguanosine), and reprogramming the tumour immune microenvironment. This provides a novel strategy for enhancing CRC patients' response to anti-PD-1 immunotherapy response.

Endostatin in disease modulation: From cancer to beyond

Angiogenesis plays a pivotal role in various pathological conditions, making it a key target in therapeutic development. Anti-angiogenic therapies are gaining traction for their potential in treating a range of angiogenesis-dependent diseases. Among these, endogenous angiogenesis inhibitors, particularly endostatin, have garnered significant attention for their therapeutic potential. While extensively studied for its anti-angiogenic effects in cancer, endostatin also exhibits anti-atherosclerotic and anti-fibrotic properties, broadening its therapeutic scope. Despite the successful clinical use of recombinant human endostatin in China for nearly two decades, its broader therapeutic potential remains underexplored. Thus, this review delves into the multifaceted applications of endostatin, examining its role in ocular diseases, inflammation, reproductive disorders, and tumor angiogenesis. Furthermore, it provides a comprehensive overview of its emerging roles beyond angiogenesis, particularly in the context of atherosclerosis and fibroproliferative conditions.

Innovative Applications of Bacteria and Their Derivatives in Targeted Tumor Therapy

Despite significant progress in cancer treatment, traditional therapies still face considerable challenges, including poor targeting, severe toxic side effects, and the development of resistance. Recent advances in biotechnology have revealed the potential of bacteria and their derivatives as drug delivery systems for tumor therapy by leveraging their biological properties. Engineered bacteria, including Escherichia coli, Salmonella, and Listeria monocytogenes, along with their derivatives─outer membrane vesicles (OMVs), bacterial ghosts (BGs), and bacterial spores (BSPs)─can be loaded with a variety of antitumor agents, enabling precise targeting and sustained drug release within the tumor microenvironment (TME). These bacteria and their derivatives possess intrinsic properties that stimulate the immune system, enhancing both innate and adaptive immune responses to further amplify therapeutic effects. The ability of bacteria to naturally accumulate in hypoxic tumor regions and their versatility in genetic modifications allow for tailored drug delivery strategies that synergistically enhance the effectiveness of chemotherapy, immunotherapy, and targeted therapies. This review comprehensively examines the fundamental principles of bacterial therapy, focusing on the strategies employed for bacterial engineering, drug loading, and the use of bacteria and their derivatives in targeted tumor therapy. It also discusses the challenges faced in optimizing bacterial delivery systems, such as safety concerns, unintended immune responses, and scalability for clinical applications. By exploring these aspects, this review provides a theoretical framework for improving bacterial-based drug delivery systems, contributing to the development of more effective and personalized cancer treatments.

Ligilactobacillus salivarius LZZAY01 accelerated autophagy and apoptosis in colon cancer cells and improved gut microbiota in CAC mice

Colorectal cancer (CRC) is one of the malignant tumors globally, with high morbidity and mortality rates. The mainstay treatment of CRC includes surgery, radiotherapy, and chemotherapy. However, these treatments are associated with a high recurrence rate, poor prognosis, and highly toxic side effects. The probiotics have the potential to prevent CRC, and they display a favorable safety performance. Probiotics could provide a potential strategy to prevent and treat CRC. The impact of LZZAY01 on cancer cell lines CT-26, HCT-116, and SW-620 was evaluated by conducting cytotoxicity and clonogenicity tests. A model of colitis-associated cancer (CAC) was established in C57BL/6j mice following induction with AOM/DSS. The levels of autophagy and apoptosis proteins, tight junction proteins, and inflammatory factors were detected by western blotting, immunofluorescence assay, and enzyme-linked immunosorbent assay. High-throughput sequencing of gut 16S rRNA was performed to analyze the abundance and diversity of the gut microbiome. LZZAY01, a new strain of Ligilactobacillus salivarius, was certified by an evolutionary tree and average nucleotide identity. LZZAY01 enhanced autophagy and apoptosis in CT-26, HCT-116, and SW-620 cell lines. It preserved the integrity of the intestinal barrier by regulating the tight junction protein ZO-1 and claudin-1. The tumor necrosis factor-α and interleukin-6 were reduced by LZZAY01. The abundance and diversity of the intestinal microbiota were enhanced, especially the beneficial bacterial species maintaining the balance of the intestinal flora such as Bifidobacterium and Lactobacillus. L. salivarius LZZAY01 improved CAC via suppressing the growth of colon cancer cells, promoting autophagy and apoptosis, enhancing intestinal tight junctions, reducing intestinal barrier degradation, modifying the gut microbiota abundance, and decreasing inflammatory reactions.IMPORTANCEAlthough similar probiotics have been shown to have anticancer potential in colorectal cancer (CRC), there is a paucity of research related to the preventive function of probiotics against CRC. And there are fewer studies about the mechanism of probiotics' preventive effects on CRC. The regulation of tumor cell proliferation and apoptosis by the active ingredients of probiotics may be one of the mechanisms of their prevention of CRC. In this study, we explored the effects of L. salivarius LZZAY01 on autophagy and apoptosis of colon cancer cells in vitro and in vivo and proposed a possible mechanism for the prevention of CRC by probiotics.

Chang-Wei-Qing Combined with PD-1 Inhibitor Alleviates Colitis-Associated Colorectal Tumorigenesis by Modulating the Gut Microbiota and Restoring Intestinal Barrier

Chang-Wei-Qing (CWQ) is a widely recognized Traditional Chinese Medicine (TCM) formulation composed of Astragalus, Codonopsis, Atractylodes, Poria, Coix seed, Akebia trifoliata Koidz, Sargentodoxa cuneata, and Vitis quinquangularis Rehd. This formulation has garnered significant interest for its positive effects in mitigating colorectal cancer, and when combined with PD-1, it affects some gut microbiota associated with tumor infiltrating lymphocytes cells. However, the biological rationale underlying the suppression of colitis-associated colorectal cancer (CAC) in AOM/DSS-treated mice by CWQ combined with PD-1 inhibitor remains to be explored. Our aim is to explore the chemopreventive effect of CWQ combined with PD-1 inhibitor on CAC, with a focus on modulating the gut microbiota. A mouse model of CAC was established using azoxymethane (AOM) and dextran sulfate sodium (DSS) treatment. Pathological evaluation of tissue samples included immunohistochemistry and hematoxylin and eosin staining. Intestinal barrier function was assessed by transmission electron microscopy. Fecal microbiota and metabolites were analyzed through 16 S rRNA gene sequencing and liquid chromatography-mass spectrometry, respectively. Mice treated with antibiotics served as models for fecal microbiota transplantation. CWQ combined with PD-1 inhibitor suppressed CAC in AOM/DSS-treated mice. This combined therapy effectively alleviated gut dysbiosis in the CAC model by increasing microbial diversity, enriching probiotic populations such as Limosilactobacillus and Bifidobacterium, and reducing pathogenic bacteria like Desulfovibrio. Additionally, CWQ combined with PD-1 inhibitor downregulated metabolites associated with the NF-kappa B signaling pathway. The combined treatment also significantly improved intestinal barrier function in CAC mice. Transmission electron microscopy of the CWQ combined with PD-1 inhibitor group showed enhanced cellular integrity, a relatively normal mitochondrial structure with intact membranes, and a more abundant, unexpanded endoplasmic reticulum, underscoring the protective effects of this combination on intestinal barrier integrity. Transcriptomic analysis further demonstrated that the combined therapy upregulated genes involved in tight and adherens junctions, while downregulating genes linked to innate immune responses. CWQ combined with PD-1 inhibitor can ameliorate dysbiosis in the AOM/DSS mouse model, with the metabolites of the gut microbiome potentially possessing anti-inflammatory activity. Moreover, CWQ combined with PD-1 inhibitor improves intestinal barrier function, thereby effectively inhibiting the occurrence and development of CAC.

Lead toxicity mitigation effect of a Lactiplantibacillus plantarum-chondroitin sulfate complex revealed by microbiome and metabolomic analyses

Lead (Pb) is a highly toxic metal with no physiological function in humans, accumulates in the body through food intake, and causes gut microbiome disorders and other hazards. In the present study, we examined the efficacy of a combination of chondroitin sulfate and Lactiplantibacillus plantarum CCFM8661 (CCFM8661 + CS) on tissue Pb accumulation and pathological damage to the liver and kidneys, gut microbiota, and fecal metabolites in Pb-exposed mice. Oral administration of CCFM8661 + CS to Pb-exposed mice reduced Pb accumulation in the liver, kidney, and bone tissues (from 3.70, 14.11 and 121.20 mg g-1 wet tissue to 2.26, 8.72 and 65.57 mg g-1 wet tissue, respectively) and increased total antioxidant capacity, superoxide dismutase, and glutathione in the liver and kidneys. Additionally, gut microbiome analysis showed that CCFM8661 + CS intervention attenuated Pb-induced perturbation in gut microbiota, altering the abundance of bacteria such as Faecalibaculum, Ruminococcaceae UCG 014, Anaerostipes, and Enterorhabdus. Untargeted metabolomics analyses showed that CCFM8661 + CS significantly increased cinnamoylglycine, hippuric acid, and equol (to 31.24, 28.77 and 20.13 times the baseline, respectively) and decreased guanine and 4-coumaric acid (0.30 and 0.09 times the baseline, respectively) in the feces, affecting pathways such as purine and amino acid metabolism. Further analyses showed that promoting Pb excretion and restoring the Pb-impaired gut microbiome and its metabolism may be important contributors to CCFM8661 + CS alleviation of Pb toxicity.

Gut microbiota and D-ribose mediate the anti-colitic effect of punicalagin in DSS-treated mice

Background: Inflammatory bowel disease (IBD) is an increasing health burden worldwide. Punicalagin, a bioactive component rich in pomegranate rind, has been shown to attenuate chemical or bacteria-induced experimental colitis in mice, but whether punicalagin exerts its function through modulating gut microbiota and metabolites remains unexplored. Results: Punicalagin (100 mg per kg per day) administered orally to mice alleviated dextran-sodium sulfate (DSS)-induced colitis. Gut microbiota analyzed by 16S rRNA sequencing showed that punicalagin altered gut microbiota by increasing the Lachnospiraceae_NK4A136_group and Bifidobacterium abundance. To evaluate the effect of punicalagin-modulated microbiota and its metabolites in colitis mice, we transplanted fecal microbiota and sterile fecal filtrate (SFF) to mice treated with oral antibiotics. The results of fecal microbiota transplantation (FMT) demonstrated that punicalagin's anti-colitic effect is transferable by transplanting punicalagin-modulated gut microbiota and its metabolites. Additionally, we discovered that punicalagin-modulated sterile fecal filtrate also exhibits anti-colitis effects, as evidenced by improved intestinal barrier integrity and decreased inflammation. Subsequently, fecal metabolites were analyzed using liquid chromatography-mass spectrometry (LC-MS). The analysis revealed that punicalagin significantly increased the level of D-ribose. In vitro experiments showed that D-ribose has both anti-inflammatory and antioxidant properties. Furthermore, D-ribose significantly mitigated DSS-induced colitis symptoms in mice. Conclusions: Overall, this study demonstrated that gut microbiota and its metabolites partly mediate the protective effect of punicalagin against DSS-induced colitis in mice. D-ribose is a key metabolite that contributes to the anti-colitic effect of punicalagin in mice.

Atox1 regulates macrophage polarization in intestinal inflammation via ROS-NLRP3 inflammasome pathway

BACKGROUND

Inflammation and oxidative stress play an important role in the pathophysiology of inflammatory bowel disease (IBD). This study aimed to explore the effects of copper chaperone Antioxidant-1 (Atox1) on macrophages in a mouse model of intestinal inflammation.

METHODS

A mouse model of TNBS-induced colitis was established and verified using the disease activity index. Atox1 conditional knockout mice were applied. The proportion of macrophages in colonic lamina propria mononuclear cells and ROS production were analyzed using flow cytometry. Inflammatory cytokines were measured using ELISA. Expression of macrophage M1/M2 polarization markers, p47phox, NLRP3, and Caspase-1 p20 was measured using quantitative RT-PCR and Western blotting.

RESULTS

Atox1 expression was up-regulated in colon tissues of TNBS-induced colitis mice. Macrophages isolated from TNBS-induced colitis mice showed M1 polarization and nuclear translocation of Atox1. Inhibiting copper chaperone activity decreased p47phox, ROS production, and M1 polarization induced by CuCl2 in macrophages. TNBS induced up-regulation of inflammatory cytokines, M1 polarization markers, and p47phox expression in mice, an effect which was preempted by Atox1 knockout. Inflammatory cytokines and expression of M1 polarization markers, p47phox, NLRP3, Caspase-1 p20 were also increased in macrophages isolated from TNBS-induced colitis mice. These changes were alleviated in mice with Atox1 knockout. The effects of Atox1 on macrophage polarization were mediated via the ROS-NLRP3 inflammasome pathway.

CONCLUSION

Atox1 plays a pro-inflammatory role, promotes M1 polarization of macrophages, and increases the concentrations of pro-inflammatory cytokines in intestinal tissue by regulating the ROS-NLRP3 inflammasome pathway. Atox1 is a potential therapeutic target in IBD.

Effects of probiotic supplementation on chronic inflammatory process modulation in colorectal carcinogenesis

The current study investigated the potential effects of probiotic supplementation on colorectal carcinogenesis chemically induced with 1,2-dimethylhydrazine (DMH) and treated with 5-fluorouracil (5FU)-based chemotherapy in mice. Animals were randomly allocated in five different groups: Control: which not receive any treatment throughout the experimental course; Colitis model group (DMH): treated with DMH; DMH+ 5FU: animals received I.P. (intraperitoneal) dose of chemotherapy on a weekly basis; DMH+PROB: animals received daily administrations (via gavage) of probiotics (Lactobacillus: acidophilus and paracasei, Bifidobacterium lactis and bifidum); and DMH+ PROB+ 5FU: animals received the same treatment as the previous groups. After ten-week treatment, mice's large intestine was collected and subjected to colon length, histopathological, periodic acid-schiff (PAS) staining and immunohistochemistry (TLR2, MyD88, NF-κB, IL-6, TLR4, TRIF, IRF-3, IFN-γ, Ki-67, KRAS, p53, IL-10, and TGF-β) analyzes. Variance (ANOVA) and Kruskal-Wallis tests were used for statistical analysis, at significance level p 0.05. Probiotics' supplementation has increased the production of Ki-67 cell-proliferation marker, reduced body weight, and colon shortening, as well as modulated the chronic inflammatory process in colorectal carcinogenesis by inhibiting NF-κB expression and mitigating mucin depletion. Thus, these findings lay a basis for guide future studies focused on probiotics' action mechanisms in tumor microenvironment which might have implications in clinical practice.

Genetically engineered bacteria: a new frontier in targeted drug delivery

Genetically engineered bacteria (GEB) have shown significant promise to revolutionize modern medicine. These engineered bacteria with unique properties such as enhanced targeting, versatility, biofilm disruption, reduced drug resistance, self-amplification capabilities, and biodegradability represent a highly promising approach for targeted drug delivery and cancer theranostics. This innovative approach involves modifying bacterial strains to function as drug carriers, capable of delivering therapeutic agents directly to specific cells or tissues. Unlike synthetic drug delivery systems, GEB are inherently biodegradable and can be naturally eliminated from the body, reducing potential long-term side effects or complications associated with residual foreign constituents. However, several pivotal challenges such as safety and controllability need to be addressed. Researchers have explored novel tactics to improve their capabilities and overcome existing challenges, including synthetic biology tools (e.g., clustered regularly interspaced short palindromic repeats (CRISPR) and bioinformatics-driven design), microbiome engineering, combination therapies, immune system interaction, and biocontainment strategies. Because of the remarkable advantages and tangible progress in this field, GEB may emerge as vital tools in personalized medicine, providing precise and controlled drug delivery for various diseases (especially cancer). In this context, future directions include the integration of nanotechnology with GEB, the focus on microbiota-targeted therapies, the incorporation of programmable behaviors, the enhancement in immunotherapy treatments, and the discovery of non-medical applications. In this way, careful ethical considerations and regulatory frameworks are necessary for developing GEB-based systems for targeted drug delivery. By addressing safety concerns, ensuring informed consent, promoting equitable access, understanding long-term effects, mitigating dual-use risks, and fostering public engagement, these engineered bacteria can be employed as promising delivery vehicles in bio- and nanomedicine. In this review, recent advances related to the application of GEB in targeted drug delivery and cancer therapy are discussed, covering crucial challenging issues and future perspectives.

Desulfovibrio in the Gut: The Enemy within?

Desulfovibrio (DSV) are sulfate-reducing bacteria (SRB) that are ubiquitously present in the environment and as resident commensal bacteria within the human gastrointestinal tract. Though they are minor residents of the healthy gut, DSV are opportunistic pathobionts that may overgrow in the setting of various intestinal and extra-intestinal diseases. An increasing number of studies have demonstrated a positive correlation between DSV overgrowth (bloom) and various human diseases. While the relationship between DSV bloom and disease pathology has not been clearly established, mounting evidence suggests a causal role for these bacteria in disease development. As DSV are the most predominant genera of SRB in the gut, this review summarizes current knowledge regarding the relationship between DSV and a variety of diseases. In this study, we also discuss the mechanisms by which these bacteria may contribute to disease pathology.

Probiotics for the treatment of ulcerative colitis: a review of experimental research from 2018 to 2022

Ulcerative colitis (UC) has become a worldwide public health problem, and the prevalence of the disease among children has been increasing. The pathogenesis of UC has not been elucidated, but dysbiosis of the gut microbiota is considered the main cause of chronic intestinal inflammation. This review focuses on the therapeutic effects of probiotics on UC and the potential mechanisms involved. In animal studies, probiotics have been shown to alleviate symptoms of UC, including weight loss, diarrhea, blood in the stool, and a shortened colon length, while also restoring intestinal microecological homeostasis, improving gut barrier function, modulating the intestinal immune response, and attenuating intestinal inflammation, thereby providing theoretical support for the development of probiotic-based microbial products as an adjunctive therapy for UC. However, the efficacy of probiotics is influenced by factors such as the bacterial strain, dose, and form. Hence, the mechanisms of action need to be investigated further. Relevant clinical trials are currently lacking, so the extension of animal experimental findings to clinical application requires a longer period of consideration for validation.

Oxymatrine ameliorated experimental colitis via mechanisms involving inflammatory DCs, gut microbiota and TLR/NF-κB pathway

It is common knowledge that the crosstalk of gut microbiota (GM) and dendritic cells (DCs) are critical for the pathogenesis of inflammatory bowel disease (IBD). As a major bioactive constituent derived from the root of the Sophora flavescens, Oxymatrine (OMT) was used to treat IBD in China. However, it is still unknown whether OMT ameliorates IBD by regulating the crosstalk between DCs and GM. In the present study, after 10 days of OMT (100 mg/kg/day) treated mice with colitis induced by dextran sulfate sodium (DSS), the change rate of body weight, colon weight, colon weight index, colon length, DAI score and colonic pathological damage scores of colitis mice were significantly ameliorate, followed with fewer ulceration and inflammatory cell infiltration, the increased expression of IL-4 and IL-13, and the decreased expression of CCL-2, IL-33 and IFN-γ. The percents of inflammatory DCs (such as TNF-α⁺DCs, iNOS⁺DCs, CXCR5⁺DCs and E-cadherin⁺DCs) were markedly decreased, and the GM composition was regulated. Importantly, it is positive correlated between the efficacy of OMT on colitis, GM and inflammatory DCs. Meanwhile, Western blotting assay showed that OMT suppressed the activation of TLR4, Myd88, IRAK4, IRAK1, TRAF6, TAK1, TAB, MKK3, MKK6, P38, NF-κB in the TLR / NF-κB signaling pathway. In summary, OMT exhibits the protective effect against the DSS-induced experimental colitis, which was achieved by regulating the crosstalk of inflammatory DCs and GM, and inhibiting the TLR / NF-κB signaling pathway.

Intestinal bacteria and colorectal cancer: etiology and treatment

The etiology of colorectal cancer (CRC) is influenced by bacterial communities that colonize the gastrointestinal tract. These microorganisms derive essential nutrients from indigestible dietary or host-derived compounds and activate molecular signaling pathways necessary for normal tissue and immune function. Associative and mechanistic studies have identified bacterial species whose presence may increase CRC risk, including notable examples such as Fusobacterium nucleatum, Enterotoxigenic Bacteroides fragilis, and pks+ E. coli. In recent years this work has expanded in scope to include aspects of host mutational status, intra-tumoral microbial heterogeneity, transient infection, and the cumulative influence of multiple carcinogenic bacteria after sequential or co-colonization. In this review, we will provide an updated overview of how host-bacteria interactions influence CRC development, how this knowledge may be utilized to diagnose or prevent CRC, and how the gut microbiome influences CRC treatment efficacy.