Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response

Creatine-mediated ferroptosis inhibition is involved in the intestinal radioprotection of daytime-restricted feeding

Ionizing radiation-induced intestinal injury (IRIII) is a catastrophic disease lack of sufficient medical countermeasures currently. Regulation of the gut microbiota through dietary adjustments is a potential strategy to mitigate IRIII. Time-restricted feeding (TRF) is an emerging behavioral nutrition intervention with pleiotropic health benefits. Whether this dietary pattern influences the pathogenesis of IRIII remains vague. We evaluated the impact of TRF on intestinal radiosensitivity in this study and discovered that only daytime TRF (DTRF), not nighttime TRF, could ameliorate intestinal damage in mice that received a high dose of IR. Faecal metagenomic and metabolomic studies revealed that the intestinal creatine level was increased by approximate 9 times by DTRF, to which the Bifidobacterium pseudolongum enrichment contribute. Further investigations showed that creatine could activate the energy sensor AMP-activated protein kinase in irradiated enterocytes and induce phosphorylation of acetyl-CoA carboxylase, resulting in reduced production of polyunsaturated fatty acids and reduced ferroptosis after IR. The administration of creatine mitigated IRIII and reduced bacteremia and proinflammatory responses. Blockade of creatine import compromised the ferroptosis inhibition and mitigation of DTRF on IRIII. Our study demonstrates a radioprotective dietary mode that can reshape the gut microbiota and increase intestinal creatine, which can suppress IR-induced ferroptosis, thereby providing effective countermeasures for IRIII prevention.

Limosilactobacillus reuteri - a probiotic gut commensal with contextual impact on immunity

The gut microbiome plays a key role in human health, influencing various biological processes and disease outcomes. The historical roots of probiotics are traced back to Nobel Laureate Élie Metchnikoff, who linked the longevity of Bulgarian villagers to their consumption of sour milk fermented by Lactobacilli. His pioneering work led to the global recognition of probiotics as beneficial supplements, now a multibillion-dollar industry. Modern probiotics have been extensively studied for their immunomodulatory effects. Limosilactobacillus reuteri (L. reuteri), a widely used probiotic, has garnered significant attention for its systemic immune-regulatory properties, particularly in relation to autoimmunity and cancer. This review delves into the role of L. reuteri in modulating immune responses, with a focus on its impact on systemic diseases.

Gut microbiota in hepatocellular carcinoma immunotherapy: immune microenvironment remodeling and gut microbiota modification

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality, with limited treatment options at advanced stages. The gut microbiota, a diverse community of microorganisms residing in the gastrointestinal tract, plays a pivotal role in regulating immune responses through the gut-liver axis. Emerging evidence underscores its impact on HCC progression and the efficacy of immunotherapy. This review explores the intricate interactions between gut microbiota and the immune system in HCC, with a focus on key immune cells and pathways involved in tumor immunity. Additionally, it highlights strategies for modulating the gut microbiota - such as fecal microbiota transplantation, dietary interventions, and probiotics - as potential approaches to enhancing immunotherapy outcomes. A deeper understanding of these mechanisms could pave the way for novel therapeutic strategies aimed at improving patient prognosis.

Microbiota-centered interventions to boost immune checkpoint blockade therapies

Immune checkpoint blockade therapies have markedly advanced cancer treatment by invigorating antitumor immunity and extending patient survival. However, therapeutic resistance and immune-related toxicities remain major concerns. Emerging evidence indicates that microbial dysbiosis diminishes therapeutic response rates, while a diverse gut ecology and key beneficial taxa correlate with improved treatment outcomes. Therefore, there is a growing understanding that manipulating the gut microbiota could boost therapy efficacy. This review examines burgeoning methods that target the gut microbiome to optimize therapy and innovative diagnostic tools to detect dysbiosis, and highlights challenges that remain to be addressed in the field.

Gut microbiota in melanoma: Effects and pathogeneses

The gut microbiota exhibits intricate connections with the body's immune system and holds significant implications for various diseases and cancers. Currently, accumulating evidence suggests a correlation between the composition of the gut microbiota and the development, treatment, and prognosis of melanoma. However, the underlying pathogenesis remains incompletely elucidated. In this comprehensive review, we present an in-depth review of the role played by gut microbiota in melanoma tumorigenesis, growth, metastasis, treatment response, and prognosis. Furthermore, we discuss the potential utility of gut microbiota as a promising prognostic marker. Lastly, we summarize three routes through which gut microbiota influences melanoma: immunity, aging, and the endocrine system. By modulating innate and adaptive immunity in patients with melanoma across different age groups and genders, the gut microbiota plays a crucial role in anti-tumor immune regulation from tumorigenesis to prognosis management, thereby impacting tumor growth and metastasis. This review also addresses current study limitations while highlighting future research prospects.

Harnessing the human microbiome and its impact on immuno-oncology and nanotechnology for next-generation cancer therapies

The integration of microbiome research and nanotechnology represents a significant advancement in immuno-oncology, potentially improving the effectiveness of cancer immunotherapies. Recent studies highlight the influential role of the human microbiome in modulating immune responses, presenting new opportunities to enhance immune checkpoint inhibitors (ICIs) and other cancer therapies. Nanotechnology offers precise drug delivery and immune modulation capabilities, minimizing off-target effects while maximizing therapeutic outcomes. This review consolidates current knowledge on the interactions between the microbiome and the immune system, emphasizing the microbiome's impact on ICIs, and explores the incorporation of nanotechnology in cancer treatment strategies. Additionally, it provides a forward-looking perspective on the synergistic potential of microbiome modulation and nanotechnology to overcome existing challenges in immuno-oncology. This integrated approach may enhance the personalization and effectiveness of next-generation cancer treatments, paving the way for transformative patient care.

Age- and diet-instructed metabolic rewiring of the tumor-immune microenvironment

The tumor-immune microenvironment (TIME) plays a critical role in tumor development and metastasis, as it influences the evolution of tumor cells and fosters an immunosuppressive state by intervening the metabolic reprogramming of infiltrating immune cells. Aging and diet significantly impact the metabolic reprogramming of the TIME, contributing to cancer progression and immune evasion. With aging, immune cell function declines, leading to a proinflammatory state and metabolic alterations such as increased oxidative stress and mitochondrial dysfunction, which compromise antitumor immunity. Similarly, dietary factors, particularly high-fat and high-sugar diets, promote metabolic shifts, creating a permissive TIME by fostering tumor-supportive immune cell phenotypes while impairing the tumoricidal activity of immune cells. In contrast, dietary restrictions have been shown to restore immune function by modulating metabolism and enhancing antitumor immune responses. Here, we discuss the intricate interplay between aging, diet, and metabolic reprogramming in shaping the TIME, with a particular focus on T cells, and highlight therapeutic strategies targeting these pathways to empower antitumor immunity.

Influence of high-fiber diet on ipilimumab-induced gastrointestinal toxicity in metastatic melanoma

BACKGROUND

The anti-cytotoxic T-lymphocyte-associated protein (CTLA)-4 antibody ipilimumab (ipi) and the anti-programmed death (PD)-1 antibody nivolumab (nivo) are routinely used to treat metastatic melanoma. One of the most frequent severe immune-related adverse events (irAEs) induced by ipi is diarrhea as a symptom of ir-colitis. Here, the composition of the gut microbiome was shown to correlate with the risk of developing colitis. Stimulated by a patient case and the knowledge that nutrition influences the gut microbiome, we performed a retrospective analysis to evaluate dietary habits and the frequency of colitis in patients with ipi ± nivo therapy.

METHODS

Patients with metastasized stage III or IV melanoma who were treated with ipi ± nivo and who were willing to take part in a nutritional survey and interview at least three months after the first ipi dose were included into the study. Dietary habits were investigated using the food frequency questionnaire (FFQ) and personal interviews. The calculated daily intake of calories, carbohydrates, fats, proteins, sugars, and dietary fiber was correlated with the development of ir-colitis.

RESULTS

20 patients were included into this study, and all but one received ipi-nivo combination therapy. The median age was 59.5 years, and 60 % were male. 4 of 20 patients (20 %) developed ir-colitis grade 3 after two cycles in the median and were managed with at least high-dose corticosteroids. The FFQ and interview were conducted in a median of six months after treatment initiation. In general, the interviewed patients followed a typical western-pattern diet based on carbohydrates as the main, followed by fat as the second most important energy substrate. Comparing patients with and without colitis our investigation revealed that the achieved amount of recommended dietary fiber intake per total energy intake (TEI) was negatively associated with diarrhea and colitis (p = 0.061). No significant differences concerning daily intake of calories, carbohydrates, fats, proteins, and sugar were found. In addition, no significant differences were found among patients in terms of their age, gender, tobacco use, supplement intake, therapy regime, or body mass index (BMI).

CONCLUSIONS

This pilot study gives first hints that nutritional habits might influence treatment tolerability to ipi ± nivo therapy. A high-fiber diet might protect against ir-colitis and diarrhea in ipi-treated patients. This observation should be validated by a prospective randomized interventional trial. However, if it is possible to prevent ir-colitis by a high-fiber diet that would be of great impact on routine patient treatment.

Gut Microbiota in Immuno-Oncology: A Practical Guide for Medical Oncologists With a Focus on Antibiotics Stewardship

The gut microbiota has emerged as a critical determinant of immune checkpoint inhibitor (ICI) efficacy, resistance, and toxicity. Retrospective and prospective studies profiling the taxonomic composition of intestinal microbes of patients treated with ICI have revealed specific gut microbial signatures associated with response. By contrast, dysbiosis, which can be caused by chronic inflammatory processes (such as cancer) or comedications, is a risk factor of resistance to ICI. Recent large-scale meta-analyses have confirmed that antibiotic (ATB) use before or during ICI therapy alters the microbiota repertoire and significantly shortens overall survival, even after adjusting for prognostic factors. These results underscore the importance of implementing ATB stewardship recommendations in routine oncology practice. Microbiota-centered interventions are now being explored to treat gut dysbiosis and optimize ICI responses. Early-phase clinical trials evaluating fecal microbiota transplantation (FMT) from ICI responders or healthy donors have shown that this approach is safe and provided preliminary data on potential efficacy to overcome both primary and secondary resistance to ICI in melanoma, non-small cell lung cancer, and renal cell carcinoma. More targeted interventions including live bacterial products including Clostridium butyricum and Akkermansia massiliensis represent novel microbiome-based adjunct therapies. Likewise, dietary interventions, such as high-fiber diets, have shown promise in enhancing ICI activity. In this ASCO Educational Book, we summarize the current state-of-the-evidence of the clinical relevance of the intestinal microbiota in cancer immunotherapy and provide a practical guide for ATB stewardship.

Intestinal Microbiome Modulation of Therapeutic Efficacy of Cancer Immunotherapy

Bacteria are associated with certain cancers and may induce genetic instability and cancer progression. The gut microbiome modulates the response to cancer therapy. Training machine learning models with response associated taxa or bacterial genes predict patients' response to immunotherapies with moderate accuracy. Clinical trials targeting the gut microbiome to improve immunotherapy efficacy have been conducted. While single bacterial strains or small consortia have not be reported yet to be successful, encouraging results have been reported in small single arm and randomized studies using transplant of fecal microbiome from cancer patients who successfully responded to therapy or from healthy volunteers.

Immune checkpoint inhibitor (ICI) therapy in central nervous system cancers: State-of-the-art and future outlook

Invasive central nervous system (CNS) cancers are an area where the development of breakthrough therapies is urgently needed. For instance, conditions such as glioblastoma multiforme (GBM) are associated with poor clinical prognosis, with the majority of trials offering no improvement to marginally enhanced survival. Unleashing the potential of targeting the immune system in CNS cancers has gained attention in recent years. Inhibition of immune checkpoints such as CTLA-4, PD-1/PD-L1, TIM-3, and LAG-3 has been attempted in recent trials. While potentially offering a notable edge over other immunotherapies, multi-organ adverse events have been found with the administration of immune checkpoint inhibitors (ICIs). The present review captures the state-of-the-art evidence on ICI treatments in different CNS cancers. Also, we discuss the value of combinational therapies involving ICIs as well as next-generation therapeutics such as bispecific antibodies targeting PD-1/LAG-3/TIM-3 and CRISPR-Cas9-edited PD-1-knock-out checkpoint-resistant CAR T-cells.

Microbiome metabolism of dietary phytochemicals controls the anticancer activity of PI3K inhibitors

Phosphatidylinositol 3-kinase (PI3K) signaling is both the effector pathway of insulin and among the most frequently activated pathways in human cancer. In murine cancer models, the efficacy of PI3K inhibitors is dramatically enhanced by a ketogenic diet, with a proposed mechanism involving dietary suppression of insulin. Here, we confirm profound diet-PI3K anticancer synergy but show that it is, surprisingly, unrelated to diet macronutrient composition. Instead, the diet-PI3K interaction involves microbiome metabolism of ingested phytochemicals. Specifically, murine ketogenic diet lacks the complex spectrum of phytochemicals found in standard chow, including the soy phytochemicals soyasaponins. We find that soyasaponins are converted by the microbiome into inducers of hepatic cytochrome P450 enzymes, and thereby lower PI3K inhibitor blood levels and anticancer activity. A high-carbohydrate, low-phytochemical diet synergizes with PI3K inhibition to treat cancer in mice, as do antibiotics that curtail the gut microbiome. Thus, diet impacts anticancer drug activity through phytochemical-microbiome-liver interactions.

Microbiota mechanisms in cancer progression and therapy

The composition of the microbiota in patients has been shown to correlate with cancer progression and response to therapy, highlighting unique opportunities to improve patient outcomes. In this review, we discuss the challenges and advancements in understanding the chemical mechanisms of specific microbiota species, pathways, and molecules involved in cancer progression and treatment. We also describe the modulation of cancer and immunotherapy by the microbiota, along with approaches for investigating microbiota enzymes and metabolites. Elucidating these specific microbiota mechanisms and molecules should offer new opportunities for developing enhanced diagnostics and therapeutics to improve outcomes for cancer patients. Nonetheless, many microbiota mechanisms remain to be determined and require innovative chemical genetic approaches.

The Microbiome and Cancer: A Translational Science Review

Importance

Growing evidence suggests that microbes located within the gastrointestinal tract and other anatomical locations influence the development and progression of diseases such as cancer.

Observations

Clinical and preclinical evidence suggests that microbes in the gastrointestinal tract and other anatomical locations, such as the respiratory tract, may affect carcinogenesis, development of metastases, cancer treatment response, and cancer treatment-related adverse effects. Within tumors of patients with cancer, microbes may affect response to treatment, and therapies that reduce or eliminate these microbes may improve outcomes in patients with cancer. Modulating gastrointestinal tract (gut) microbes through fecal microbiota transplant and other strategies such as dietary intervention (eg, high-fiber diet intervention) has improved outcomes in small studies of patients treated with cancer immunotherapy. In contrast, disruption of the gut microbiota by receipt of broad-spectrum antibiotics prior to treatment with cancer immunotherapy has been associated with poorer overall survival and higher rates of adverse effects in patients treated with immune checkpoint blockade for solid tumors and also with chimeric antigen receptor T-cell therapy for hematologic malignancies.

Conclusions and Relevance

Microbes in the gut and other locations in the body may influence the development and progression of cancer and may affect the response to adverse effects from cancer therapy. Future therapies targeting microbes in the gut and other locations in the body could potentially improve outcomes in patients with cancer.

The gut microbiome and cancer: from tumorigenesis to therapy

The gut microbiome has a crucial role in cancer development and therapy through its interactions with the immune system and tumour microenvironment. Although evidence links gut microbiota composition to cancer progression, its precise role in modulating treatment responses remains unclear. In this Review, we summarize current knowledge on the gut microbiome's involvement in cancer, covering its role in tumour initiation and progression, interactions with chemotherapy, radiotherapy and targeted therapies, and its influence on cancer immunotherapy. We discuss the impact of microbial metabolites on immune responses, the relationship between specific bacterial species and treatment outcomes, and potential microbiota-based therapeutic strategies, including dietary interventions, probiotics and faecal microbiota transplantation. Understanding these complex microbiota-immune interactions is critical for optimizing cancer therapies. Future research should focus on defining microbial signatures associated with treatment success and developing targeted microbiome modulation strategies to enhance patient outcomes.

New insights into gut microbiota-prostate cancer crosstalk

Recent evidence underscores a reciprocal relationship between the gut microbiota and prostate cancer (PCa). Dysbiosis, often driven by Western dietary habits and antibiotic use, can heighten systemic inflammation and hinder antitumor immunity, thereby fostering PCa onset and progression. Conversely, certain gut microbes and their metabolites may protect against tumor growth by modulating immune and hormonal pathways that impact therapeutic responses, including androgen deprivation therapy (ADT). Emerging evidence links gut microbial shifts to PCa aggressiveness, potentially sustaining local androgen production and promoting resistance. In this review, we explore current understanding of the gut-PCa interplay, highlighting key knowledge gaps and the need for further research to clarify how targeting the microbiome might influence PCa outcomes.

Gut microbiota reshapes the TNBC immune microenvironment: Emerging immunotherapeutic strategies

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited treatment options and poor prognosis. The gut microbiota, a diverse community of microorganisms in the gastrointestinal tract, plays a crucial role in regulating immune responses through the gut-immune axis. Recent studies have highlighted its significant impact on TNBC progression and the efficacy of immunotherapies. This review examines the interactions between gut microbiota and the immune system in TNBC, focusing on key immune cells and pathways involved in tumor immunity. It also explores microbiota modulation strategies, including probiotics, prebiotics, dietary interventions, and fecal microbiota transplantation, as potential methods to enhance immunotherapeutic outcomes. Understanding these mechanisms offers promising avenues for improving treatment efficacy and patient prognosis in TNBC.

Gut microbiota in cancer initiation, development and therapy

Cancer has long been associated with genetic and environmental factors, but recent studies reveal the important role of gut microbiota in its initiation and progression. Around 13% of cancers are linked to infectious agents, highlighting the need to identify the specific microorganisms involved. Gut microbiota can either promote or inhibit cancer growth by influencing oncogenic signaling pathways and altering immune responses. Dysbiosis can lead to cancer, while certain probiotics and their metabolites may help reestablish micro-ecological balance and improve anti-tumor immune responses. Research into targeted approaches that enhance therapy with probiotics is promising. However, the effects of probiotics in humans are complex and not yet fully understood. Additionally, methods to counteract harmful bacteria are still in development. Early clinical trials also indicate that modifying gut microbiota may help manage side effects of cancer treatments. Ongoing research is crucial to understand better how gut microbiota can be used to improve cancer prevention and treatment outcomes.

Global genetic diversity of human gut microbiome species is related to geographic location and host health

The human gut harbors thousands of microbial species, each exhibiting significant inter-individual genetic variability. Although many studies have associated microbial relative abundances with human-health-related phenotypes, the substantial intraspecies genetic variability of gut microbes has not yet been comprehensively considered, limiting the potential of linking such genetic traits with host conditions. Here, we analyzed 32,152 metagenomes from 94 microbiome studies across the globe to investigate the human microbiome intraspecies genetic diversity. We reconstructed 583 species-specific phylogenies and linked them to geographic information and species' horizontal transmissibility. We identified 484 microbial-strain-level associations with 241 host phenotypes, encompassing human anthropometric factors, biochemical measurements, diseases, and lifestyle. We observed a higher prevalence of a Ruminococcus gnavus clade in nonagenarians correlated with distinct plasma bile acid profiles and a melanoma and prostate-cancer-associated Collinsella clade. Our large-scale intraspecies genetic analysis highlights the relevance of strain diversity as it relates to human health.

Dietary Fiber and Cancer Management: A Twenty-Five-Year Bibliometric Review of Research Trends and Directions

Background: The global burden of cancer necessitates innovative approaches to its management and treatment. Traditional treatments like radiotherapy, immunotherapy, surgery, and chemotherapy, carry significant side effects that impact patient quality of life. Dietary fiber has attracted research interest as a potential mitigator of cancer progression and a supportive agent in cancer treatment. This bibliometric study analyzes trends in research connecting dietary fiber, cancer therapy, and gut health from April 1999 to May 2024. Methods and Results: Web of Science, PubMed, and Scopus databases were used to retrieve peer-reviewed publications from April 1999 to May 2024 on dietary fiber and cancer management. The study identifies a rising scholarly interest in dietary fiber's role in cancer management, focusing significantly on the interactions between dietary fiber and gut microbiota. These interactions are particularly noted for their influence on inflammation and cancer metastasis. The study highlights evolving research themes, the importance of specific fiber types in cancer progression, and highlights persistent foundational themes like glycosylation. Emerging areas include personalized nutrition and innovative therapeutic approaches. The geographical and institutional contributions, mainly from the United States and China, underline the significance of collaborative and interdisciplinary efforts in advancing research. Conclusion: This analysis emphasizes integrating dietary strategies in comprehensive cancer care and aims to address research gaps to develop more effective and patient-centered cancer therapy and prevention strategies.

The human microbiome: redefining cancer pathogenesis and therapy

The human microbiome has always been an important determinant of health and recently, its role has also been described in cancer. The altered microbiome could aid cancer progression, modulate chemoresistance and significantly alter drug efficacy. The broad implications of microbes in cancer have prompted researchers to investigate the microbe-cancer axis and identify whether modifying the microbiome could sensitize cancer cells for therapy and improve the survival outcome of cancer patients. The preclinical data has shown that enhancing the number of specific microbial species could restore the patients' response to cancer drugs and the microbial biomarkers may play a vital role in cancer diagnostics. The elucidation of detailed interactions of the human microbiota with cancer would not only help identify the novel drug targets but would also enhance the efficacy of existing drugs. The field exploring the emerging roles of microbiome in cancer is at a nascent stage and an in-depth scientific perspective on this topic would make it more accessible to a wider audience. In this review, we discuss the scientific evidence connecting the human microbiome to the origin and progression of cancer. We also discuss the potential mechanisms by which microbiota affects initiation of cancer, metastasis and chemoresistance. We highlight the significance of the microbiome in therapeutic outcome and evaluate the potential of microbe-based cancer therapy.

Acquired resistance to immunotherapy in solid tumors

Acquired resistance to immunotherapy (ARI) is a major challenge in solid tumors, limiting long-term success in up to 65% of patients who initially respond to immunotherapy. Defining ARI clinically remains complex, but ongoing efforts aim to establish standardized criteria. This review describes recent insights into ARI, revealing complex mechanisms involving both tumor-intrinsic mechanisms - such as antigen loss and presentation defects, interferon γ (IFNγ) insensitivity, tumor-mediated T cell exclusion, and metabolic reprogramming - as well as extrinsic factors such as inhibitory molecule upregulation, immunosuppressive cells, extracellular matrix (ECM) remodeling, and dysbiotic microbiota. Understanding the development of ARI is crucial for prevention and effective interventions. The integration of innovative strategies and translational research on appropriately collected samples is key to overcoming ARI and ensuring durable benefits for patients.

Regulatory role of gut microbiota in immunotherapy of hepatocellular carcinoma

BACKGROUND

The gut microbiota plays a role in triggering innate immunity and regulating the immune microenvironment (IME) of hepatocellular carcinoma (HCC) by acting on various signaling receptors and transcription factors through its metabolites and related molecules. Furthermore, there is an increasing recognition of the gut microbiota as a potential therapeutic target for HCC, given its ability to modulate the efficacy of immune checkpoint inhibitors (ICIs).

OBJECTIVE

This review will discuss the mechanisms of gut microbiota in modulating immunotherapy of HCC, the predictive value of efficacy, and the therapeutic strategies for modulating the gut microbiota in detail.

METHODS

We conducted a systematic literature search in PubMed, Embase, Scopus, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Chinese databases for articles involving the influence of gut microbiota on HCC immunotherapy.

RESULTS

The mechanisms underlying the effect of gut microbiota on HCC immunotherapy include gut-liver axis, tumor immune microenvironment (TIME), and antibodies. Patients who benefit from ICIs exhibit a higher abundance of gut microbiota. Antibiotics, fecal microbiota transplantation (FMT), probiotics, and prebiotics are effective methods to regulate gut microbiota.

CONCLUSION

The strong connection between the liver and gut will provide numerous opportunities for the development of microbiome-based diagnostics, treatments, or prevention strategies for HCC patients.

Nutritional strategies in oncology: The role of dietary patterns in modulating tumor progression and treatment response

Dietary interventions can influence tumor growth by restricting tumor-specific nutritional requirements, altering the nutrient availability in the tumor microenvironment, or enhancing the cytotoxicity of anticancer drugs. Metabolic reprogramming of tumor cells, as a significant hallmark of tumor progression, has a profound impact on immune regulation, severely hindering tumor eradication. Dietary interventions can modify tumor metabolic processes to some extent, thereby further improving the efficacy of tumor treatment. In this review, we emphasize the impact of dietary patterns on tumor progression. By exploring the metabolic differences of nutrients in normal cells versus cancer cells, we further clarify how dietary patterns influence cancer treatment. We also discuss the effects of dietary patterns on traditional treatments such as immunotherapy, chemotherapy, radiotherapy, and the gut microbiome, thereby underscoring the importance of precision nutrition.

Gut microbiota affects PD-L1 therapy and its mechanism in melanoma

Immune checkpoint inhibitors (ICIs), particularly PD-1/PD-L1 blockade, have shown great success in treating melanoma. PD-L1 (B7-H1, CD274), a ligand of PD-1, binds to PD-1 on T cells, inhibiting their activation and proliferation through multiple pathways, thus dampening tumor-reactive T cell activity. Studies have linked PD-L1 expression in melanoma with tumor growth, invasion, and metastasis, making the PD-1/PD-L1 pathway a critical target in melanoma therapy. However, immune-related adverse events are common, reducing the effectiveness of anti-PD-L1 treatments. Recent evidence suggests that the gut microbiome significantly influences anti-tumor immunity, with the microbiome potentially reprogramming the tumor microenvironment and overcoming resistance to anti-PD-1 therapies in melanoma patients. This review explores the mechanisms of PD-1/PD-L1 in melanoma and examines how gut microbiota and its metabolites may help address resistance to anti-PD-1 therapy, offering new insights for improving melanoma treatment strategies.

Association of dietary inflammatory index, composite dietary antioxidant index and risk of death among adult cancer survivors: findings from the National Health and Nutrition Examination Survey 2001-2018

Background

The development and progression of cancer can be impacted by the nutrients and components contained in the diet. This research seeks to explore the relationship between the antioxidant and pro-inflammatory properties of diet and the risk of all-cause mortality among cancer survivors.

Methods

Adults aged 20 and above who had been diagnosed with cancer and participated in the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018 were selected for this study. Their survival status was verified using death certificate information from the National Death Index. The study employed two established measures, the Composite Dietary Antioxidant Index (CDAI) and the Dietary Inflammatory Index (DII), to evaluate the antioxidant and inflammatory properties of participants' diets. A non-linear association between these two dietary indices and mortality was examined respectively using restricted cubic spline (RCS) regression. To quantify the relationship between the indices and mortality risk, multivariable Cox proportional hazards models were employed, generating hazard ratios and corresponding 95% confidence intervals. Furthermore, the study also explored the connection between the CDAI and DII.

Results

In this study, a total of 3,507 cancer survivors, representing an estimated 20,016,255 cancer survivors in the US, were included in the baseline analysis. The results showed that patients with lower DII or higher CDAI values had better survival rates. RCS regression revealed that both indicators showed linear relationships with all-cause mortality in the crude and adjusted models. It was consistently noted higher CDAI or lower DII was related to a reduced risk of all-cause mortality in cancer survivors in the Cox regression. Moreover, the subgroup analysis demonstrated that these associations hold true across various subgroups, lending credibility to the overall findings of the study. At last, an inverse correlation was observed between CDAI and DII in the diets of cancer survivors.

Conclusion

The research suggests that adopting a diet that low in pro-inflammatory foods and high in antioxidants may lower the all-cause mortality in cancer survivors. However, further prospective cohort studies are necessary to confirm these findings.

Lack of consistent effect of dietary fiber on immune checkpoint blockade efficacy across diverse murine tumor models

Immune checkpoint blockade (ICB) has transformed cancer treatment, but success rates remain low in most cancers. Recent research suggest that dietary fiber enhances ICB response in melanoma patients and murine preclinical models through microbiome-dependent mechanisms. Yet, the robustness of this effect across cancer types and dietary contexts remains unclear. Specifically, prior literature compared grain-based chow (high fiber) to low-fiber purified diet, but these diets differ also on other dimensions including phytochemicals. Here we investigated, in mice fed grain-based chow or purified diets with differing quantities of isolated fibers (cellulose and inulin), metabolite levels and ICB activity in multiple tumor models. The blood and fecal metabolome were relatively similar between mice fed high- and low-fiber purified diets, but differed massively between mice fed purified diets or chow, identifying the factor as diet type, independent of fiber. Tumor growth studies in three implantable and two spontaneous genetically engineered tumor models revealed that fiber has a weaker impact on ICB (anti-PD-1) efficacy than previously reported. In some models, dietary modulation impacted ICB activity, but not in a consistent direction across models. In none of the models did we observe the pattern expected if fiber controlled ICB efficacy: strong efficacy in both chow and high-fiber purified diet but low efficacy in low-fiber purified diet. Thus, dietary fiber appears to have limited or inconsistent effect on ICB efficacy in mouse models, and other dietary factors that correlate with fiber intake may underlie the clinical correlations between fiber consumption and immunotherapy outcomes.

Unlocking the power of the microbiome for successful cancer immunotherapy

In recent years, evidence has shown that the gut microbiome significantly influences responses to immunotherapy. This has sparked interest in targeting it to improve therapy outcomes and predictions of response and toxicity. Research has demonstrated that dysbiosis, often resulting from antibiotic use, can diminish the effectiveness of immune checkpoint inhibitors, and this lack of efficacy could be linked to systemic inflammation. Certain bacterial species have been identified as having beneficial and harmful effects on immunotherapy in the clinic. While a clear consensus has yet to emerge on the optimal species for therapeutic use, introducing a new microbiome into immunotherapy-refractory patients may boost their chances of responding to further treatment attempts. State-of-the-art interventions targeting the microbiome-such as fecal microbiota transplantation-are being assessed clinically for their safety and potential to enhance treatment outcomes, with promising results. Additionally, the microbiome has been leveraged for its power to predict clinical outcomes using machine learning, and surprisingly, its predictive capability is comparable to that of other described multi-biomarker clinical scores. Here, we discuss developing knowledge concerning the microbiome's significance in cancer immunotherapy and outline future strategies for maximizing its potential in immuno-oncology.

Clinical translation of microbiome research

The landscape of clinical microbiome research has dramatically evolved over the past decade. By leveraging in vivo and in vitro experimentation, multiomic approaches and computational biology, we have uncovered mechanisms of action and microbial metrics of association and identified effective ways to modify the microbiome in many diseases and treatment modalities. This Review explores recent advances in the clinical application of microbiome research over the past 5 years, while acknowledging existing barriers and highlighting opportunities. We focus on the translation of microbiome research into clinical practice, spearheaded by Food and Drug Administration (FDA)-approved microbiome therapies for recurrent Clostridioides difficile infections and the emerging fields of microbiome-based diagnostics and therapeutics. We highlight key examples of studies demonstrating how microbiome mechanisms, metrics and modifiers can advance clinical practice. We also discuss forward-looking perspectives on key challenges and opportunities toward integrating microbiome data into routine clinical practice, precision medicine and personalized healthcare and nutrition.

The gut microbiome and dietary fibres: implications in obesity, cardiometabolic diseases and cancer

Dietary fibres constitute a heterogeneous class of nutrients that are key in the prevention of various chronic diseases. Most dietary fibres are fermented by the gut microbiome and may, thereby, modulate the gut microbial ecology and metabolism, impacting human health. Dietary fibres may influence the occurrence of specific bacterial taxa, with this effect varying between individuals. The effect of dietary fibres on microbial diversity is a matter of debate. Most intervention studies with dietary fibres in the context of obesity and related metabolic disorders reveal the need for an accurate assessment of the microbiome to better understand the variable response to dietary fibres. Epidemiological studies confirm that a high dietary fibre intake is strongly associated with a reduced occurrence of many types of cancer. However, there is a need to determine the impact of intervention with specific dietary fibres on cancer risk, therapy efficacy and toxicity, as well as in cancer cachexia. In this Review, we summarize the mechanisms by which the gut microbiome can mediate the physiological benefits of dietary fibres in the contexts of obesity, cardiometabolic diseases and cancer, their incidence being clearly linked to low dietary fibre intake.

Understanding the microbiome as a mediator of bladder cancer progression and therapeutic response

Bladder cancer (BCa) remains a significant source of morbidity and mortality. BCa is one of the most expensive tumors to treat, in part because of a lack of nonsurgical options. The recent advent of immunotherapy, alone or in combination with other compounds, has improved therapeutic options. Resistance to immunotherapy remains common, and many patients do not have durable response. Recent advances indicate immunotherapy efficacy may be tied in part to the endogenous bacteria present in our body, more commonly referred to as the microbiome. Laboratory and clinical data now support the idea that a healthy microbiome is critical to effective response to immunotherapy. At the same time, pathogenic interactions between the microbiome and immune cells can also serve to drive formation of tumors, increasing the complexity of these interactions. Given the rising importance of immunotherapy in BCa, understanding how we might be able to alter the microbiome to improve therapeutic efficacy offers a novel route to improved patient care. The goal of this review is to examine our current understanding of microbial interactions with the immune system and cancer with an emphasis on BCa. We will further attempt to define both current gaps in knowledge and future directions that may yield beneficial results to the field.

Impact of the ONCOBIOME network in cancer microbiome research

The European Union-sponsored ONCOBIOME network has spurred an international effort to identify and validate relevant gut microbiota-related biomarkers in oncology, generating a unique and publicly available microbiome resource. ONCOBIOME explores the effects of the microbiota on gut permeability and metabolism as well as on antimicrobial and antitumor immune responses. Methods for the diagnosis of gut dysbiosis have been developed based on oncomicrobiome signatures associated with the diagnosis, prognosis and treatment responses in patients with cancer. The mechanisms explaining how dysbiosis compromises natural or therapy-induced immunosurveillance have been explored. Through its integrative approach of leveraging multiple cohorts across populations, cancer types and stages, ONCOBIOME has laid the theoretical and practical foundations for the recognition of microbiota alterations as a hallmark of cancer. ONCOBIOME has launched microbiota-centered interventions and lobbies in favor of official guidelines for avoiding diet-induced or iatrogenic (for example, antibiotic- or proton pump inhibitor-induced) dysbiosis. Here, we review the key advances of the ONCOBIOME network and discuss the progress toward translating these into oncology clinical practice.

The Role of the Microbiome in Cancer Therapies: Current Evidence and Future Directions

The microbiome is essential for maintaining human health and is also a key factor in the development and progression of various diseases, including cancer. Growing evidence has highlighted the microbiome's significant impact on cancer development, progression, and treatment outcomes. As research continues to unfold, the microbiome and its modulation stand out as a promising frontier in cancer research and therapy. This review highlights current literature on the interplay between various cancer treatment modalities and human microbiotas, focusing on how the microbiome may affect treatment efficacy and toxicity and its potential as a therapeutic target to enhance future outcomes.

Combining gut microbiota modulation and immunotherapy: A promising approach for treating microsatellite stable colorectal cancer

Colorectal cancer (CRC) is one of the most prevalent and lethal cancers worldwide, ranking third in incidence and second in mortality. While immunotherapy has shown promise in patients with deficient mismatch repair (dMMR) or high microsatellite instability (MSI-H), its effectiveness in proficient mismatch repair (pMMR) or microsatellite stable (MSS) CRC remains limited. Recent advances highlight the gut microbiota as a potential modulator of anti-tumor immunity. The gut microbiome can significantly influence the efficacy of immune checkpoint inhibitors (ICIs), especially in pMMR/MSS CRC, by modulating immune responses and systemic inflammation. This review explores the role of the gut microbiota in pMMR/MSS CRC, the mechanisms by which it may enhance immunotherapy, and current strategies for microbiota modulation. We discuss the potential benefits of combining microbiota-targeting interventions with immunotherapy to improve treatment outcomes for pMMR/MSS CRC patients.

The gut microbiome and dietary metabolites in the treatment of renal cell carcinoma

The gut microbiome is interlinked with renal cell carcinoma (RCC) and its response to systemic treatment. Mounting data suggests that certain elements of the gut microbiome may correlate with improved outcomes. New generation sequencing techniques and advanced bioinformatic data curation are accelerating the investigation of specific markers and metabolites that could predict treatment response. A variety of new therapeutic strategies, such as fecal microbiota transplantation, probiotic supplements, and dietary interventions, are currently being developed to modify the gut microbiome and improve anticancer therapies in patients with RCC. This review discusses the preliminary evidence indicating the role of the microbiome in cancer treatment, the techniques and tools necessary for its proper study and some of the current forms with which the microbiome can be modulated to improve patient outcomes.

Oncobiomics: Leveraging Microbiome Translational Research in Immuno-Oncology for Clinical-Practice Changes

Growing evidence suggests that cancer should not be viewed solely as a genetic disease but also as the result of functional defects in the metaorganism, including disturbances in the gut microbiota (i.e., gut dysbiosis). The human microbiota plays a critical role in regulating epithelial barrier function in the gut, airways, and skin, along with host metabolism and systemic immune responses against microbes and cancer. Collaborative international networks, such as ONCOBIOME, are essential in advancing research equity and building microbiome resources to identify and validate microbiota-related biomarkers and therapies. In this review, we explore the intricate relationship between the microbiome, metabolism, and cancer immunity, and we propose microbiota-based strategies to improve outcomes for individuals at risk of developing cancer or living with the disease.

The therapeutic promise of probiotic Bacteroides fragilis (BF839) in cancer immunotherapy

Background

Overwhelming evidence suggests that the gut microbiota modulates tumor response to immune checkpoint inhibitors (ICIs). The probiotic Bacteroides fragilis (BF839) was extensively used in China to improve gut microbiota dysbiosis-related symptoms. We hypothesized that probiotic BF839 could enhance tumor sensitivity to ICIs.

Methods

In the preclinical studies, mice received BF839 orally, PD-1 intraperitoneal injection, or a combination therapy of the two agents. The antitumor effect of BF839 was investigated by assessing the tumor growth and tumor immune microenvironment. Mice fecal samples were collected for 16S rRNA sequencing. Fresh tumor samples were collected for 16S RNA sequencing. The data of 29 patients with advanced solid tumor who received BF839 adjuvant therapy were retrospectively evaluated. The primary endpoint was overall survival (OS).

Results

Among patients with advanced solid tumors undergoing ICIs and chemotherapy, patients in BF839 long-term adjuvant treatment group had longer OS (p = 0.0101) than the BF839 short-term adjuvant treatment group. In the preclinical studies, we found that monotherapy with BF839 or anti-PD-1 antibody significantly inhibit tumor growth. Interestingly, BF839 worked synergistically with anti-PD-1 antibody and induced tumor regression, mediated by increased CD8+T cell infiltration. Mechanistically, BF839 induced tumor suppression was regulated by the cGAS-STING pathway. 16S rRNA sequencing results of mice fecal samples showed that BF839 treatment increased gut microbiota diversity.

Conclusion

Overall, our data suggest that BF839 enhanced tumor sensitivity to ICIs through cGAS-STING signaling. In the future, the application of probiotic BF839 to regulate gut microbiota may be a new strategy to enhance the efficacy of ICIs.

SITC strategic vision: prevention, premalignant immunity, host and environmental factors

Cancer immunotherapy has improved the survival of a subset of patients by harnessing the power of the immune system to find and destroy malignant cells. The immune system also protects the host by destroying developing premalignant and malignant tumors. Advancing our knowledge of premalignant immunity and immune changes seen in lesions that develop into invasive cancer versus those that regress offers an exciting opportunity to leverage the immune system for immune prevention and immune interception of premalignancy. Understanding the immune environment of premalignant lesions and how chronic inflammation plays a central role in the evolution of premalignancy is essential for developing effective immunoprevention and immune interceptions. Factors such as host genomics and environmental factors that affect premalignant immunity and the outcome of advanced cancers are equally important in determining the response to immunotherapy. The broad use of antibiotics and factors such as obesity can disrupt a healthy gut microbiome and drive chronic inflammation that suppresses preventive immunity or the antitumor immune response required for successful immunotherapy in advanced cancers. Modifiable lifestyle factors such as diet, obesity, smoking, and stress should be considered in designing immune prevention and interception studies, as well as for patients who receive immunotherapy for advanced cancer treatment. Other factors, such as the overall immune health of patients and existing comorbidities, affect both premalignant immunity and response to immunotherapy and, therefore, should be considered in managing patients with or without cancer. The Society for Immunotherapy of Cancer previously developed an overarching manuscript regarding the challenges and opportunities that exist in cancer immunotherapy, and this manuscript serves as an in-depth follow-up regarding the topics of premalignant immunity, immune interception, and immunoprevention, and the impact of the host on responding to immunotherapy.

The Benefits and Safety of Monoclonal Antibodies: Implications for Cancer Immunotherapy

Monoclonal antibodies (mAbs) have transformed cancer treatment by providing highly targeted and effective therapies that specifically attack cancer cells, thus reducing the likelihood of adverse events (AEs) in patients. mAbs exert their action through various mechanisms, such as receptor blockade, antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and inhibition of immune checkpoints (eg, PD-1, PD-L1, and CTLA-4). These therapies have led to significant improvements in the treatment of several cancers, including HER2-positive breast cancer, non-small cell lung cancer (NSCLC), and melanoma. The efficacy of mAb therapy in cancer treatment is influenced by various intrinsic and extrinsic factors, such as environmental exposures, psychosocial factors, infection status, ways of life, and tumor microenvironment (TME), all of which can impact immune responses and treatment outcomes. Notably, the therapeutic benefits of mAbs are often accompanied by immune-related AEs (irAEs), which can vary from mild to severe and affect multiple organ systems. The dual nature of mAbs-stimulating antitumor immune responses while also inducing immune-related side effects-presents a notable challenge in clinical practice. This review highlights the importance of proactive strategies for managing irAEs, such as early detection, corticosteroid use, targeted immunosuppressive treatments, and the urgent need for reliable predictive biomarkers to improve treatment outcomes. Advancements in the prevention, prediction, and management of irAEs are essential to enhance the safety and effectiveness of mAb-based therapies, ultimately aiming to improve cancer patient outcomes.

Microbial Ecosystem Therapeutics 4 (MET4) elicits treatment-specific IgG responses associated with changes in gut microbiota in immune checkpoint inhibitor recipients with advanced solid tumors

BACKGROUND

Gut microbiome modulation has shown promise in its potential to treat cancer in combination with immunotherapy. Mechanistically, the pathways and routes by which gut microbiota may influence systemic and antitumor immunity remain uncertain. Here, we used blood and stool samples from Microbial Ecosystem Therapeutic 4 (MET4)-IO, an early-phase trial testing the safety and engraftment of the MET4 bacterial consortium in immune checkpoint inhibitor recipients, to assess how MET4 may affect systemic immunity.

METHODS

Circulating antibody responses induced by MET4 were assessed using an antimicrobial antibody flow cytometry assay on pretreatment and post-treatment plasma. Antibody responses were associated with taxonomic changes in stool identified by metagenomic sequencing. Mass cytometry was performed on peripheral blood mononuclear cells to identify shifts in circulating immune subsets associated with antibody responses.

RESULTS

Increases in circulating anti-MET4 immunoglobulin G (IgG) responses were measured by flow cytometry post-consortium treatment in MET4 recipients, but not untreated control participants, with five individuals displaying notably higher antibody responses. Stronger IgG responses were associated with greater increases in multiple taxa, including MET4 microbe Collinsella aerofaciens, which was previously linked with immune checkpoint response. However, these taxa were not enriched in the IgG-bound fraction post-MET4 treatment. Greater increases in circulating B cells and FoxP3+ CD4+ T cells post-MET4 treatment were observed in the blood of high IgG responders, while CD14+ and CD16+ monocyte populations were decreased in these individuals.

CONCLUSION

These results demonstrate the induction of treatment-specific circulating humoral immunity by a bacterial consortium and suggest potential mechanisms by which gut microbes may contribute to antitumor immunity.

Assessing the impact of probiotics on immunotherapy effectiveness and antibiotic-mediated resistance in cancer: a systematic review and meta-analysis

Background

Probiotics have been demonstrated to exert a potential clinical enhancing effect in cancer patients receiving immune checkpoint inhibitors (ICIs), while antibiotics exert a detrimental impact. Prior meta-analysis papers have substantial limitations and are devoid of recent published studies. Therefore, this study aimed to perform an updated meta-analysis and, for the first time, assess whether probiotics can restore the damage of antibiotics to immunotherapy.

Methods

A comprehensive literature search was conducted in three English databases and three Chinese databases with a cutoff date of August 11, 2024. The methodological quality of the studies was evaluated using the Newcastle-Ottawa Quality Assessment Scale (NOS) or the Revised Cochrane risk-of-bias tool (RoB 2). Engauge Digitizer v12.1 was employed to extract hazard ratios (HRs) with 95% confidence interval (CI) for survival outcomes when these data were not explicitly provided in the manuscripts. Meta-analysis was conducted using Stata 14 software.

Results

The study sample comprised eight retrospective and four prospective studies, involving a total of 3,142 participants. The findings indicate that probiotics significantly prolong the overall survival (OS) (I2 = 31.2%; HR=0.58, 95% CI: 0.46-0.73, p < 0.001) and progression-free survival (PFS) (I2 = 65.2%; HR=0.66, 95% CI: 0.54-0.81, p < 0.001) in cancer patients receiving ICIs, enhance the objective response rate (ORR) (I2 = 33.5%; OR=1.75, 95% CI: 1.27-2.40, p = 0.001) and disease control rate (DCR) (I2 = 50.0%; OR=1.93, 95% CI: 1.11-3.35, p = 0.002). For non-small cell lung cancer (NSCLC) patients exposed to antibiotics, the use of probiotics was associated with superior OS (I2 = 0.0%; HR=0.45, 95% CI: 0.34-0.59, p < 0.001) and PFS (I2 = 0.0%; HR=0.48, 95% CI: 0.38-0.62, p < 0.001) when compared to non-users. Subgroup differences were observed regarding the cancer type (P=0.006) and ethnic backgrounds (P=0.011) in OS.

Conclusions

The meta-analysis findings suggest that probiotics can effectively extend the survival of cancer treated with ICIs. In NSCLC, probiotics appear to mitigate the negative impact of antibiotics on immunotherapy effectiveness, which has profound clinical significance. Nevertheless, additional large-scale, high-quality randomized controlled trials are necessary to further validate these findings.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=579047, identifier CRD42024579047.

Plant based enteral nutrition outperforms artificial nutrition in mitigating consequences of antibiotic-induced dysbiosis in mice and humans

Malnutrition, gut inflammation, and antibiotic induced dysbiosis (AID) are omnipresent risk factors for poor clinical outcomes among critically ill patients. We previously showed that commercially available plant-based enteral nutrition (PBEN) preserves a commensal microbiome when compared to commonly used forms of commercially available artificial enteral nutrition (AEN). This study reveals that PBEN is superior to artificial enteral nutrition (AEN) in recovering from antibiotic-induced dysbiosis (AID) in mice and humans. PBEN effectively mitigates anemia, leukopenia, restores naïve lymphocyte populations, and reduces bone marrow myeloid cell expansion. Animals randomized to PBEN also fared better in response to infectious challenges after antibiotics. A pilot clinical study validated these findings, showing increased gut commensals, reduced pathogens, and improved leukocyte balance in critically ill patients receiving PBEN compared to AEN. These results suggest PBEN offers a practical dietary approach to mitigate antibiotic-associated complications and improve clinical outcomes among hospitalized patients requiring supplemental nutrition.

Colon health benefits of plant-derived exosome-like nanoparticles via modulating gut microbiota and immunity

Exosomes are nanoscale particles with a lipid bilayer membrane that were first identified in mammalian cells. Plant-derived exosome-like nanoparticles (PELNs) share structural and molecular similarities with mammalian exosomes, including lipids, proteins, microRNA (miRNA), and plant-derived metabolites. Owing to their unique characteristics, such as outstanding stability, low immunogenicity, high biocompatibility, and sustainability, PELNs have emerged as promising natural bioactive agents with the capacity for cross-kingdom cellular regulation. Dietary supplementation with PELNs, particularly from fruits and vegetables, has demonstrated health benefits. An increasing number of studies have indicated the beneficial effects of PELNs on colon health. This review summarizes the isolation and characterization of PELNs, and their stability, uptake, and distribution after oral ingestion. Furthermore, this review emphasizes the interactions between PELNs, gut microbiota, and the gut immune system, including the uptake of PELNs by gut microbiota, modulation of gut bacteria metabolism, and immune responses by PELNs. Additionally, the applications of PELNs as bioactive components and drug carriers targeting the colon are reviewed. In summary, PELNs represent a versatile and natural approach to improve colon health, with potential applications in both therapeutic and preventive healthcare strategies.

Dietary index for gut microbiota, a novel protective factor for the prevalence of chronic kidney diseases in the adults: insight from NHANES 2007-2018

Introduction

This study explore the association between the dietary index for gut microbiota (DI-GM) and the prevalence of chronic kidney disease (CKD).

Method

A cross-sectional study of participants aged ≥20 years using the data drawn from NHANES (2007-2018). DI-GM is comprised 14 dietary components (10 beneficial and 4 unfavorable). CKD diagnosis based on urine albumin-to-creatinine ratio (uACR) and estimated glomerular filtration rate (eGFR). Logistic regression models were employed to evaluate the relationship between DI-GM and CKD while controlling for various covariates. Additionally, a spline smooth analysis was performed. Subgroup and interaction analyses were conducted to investigate whether any factors modified this relationship.

Results

A total of 28,843 participants were eligible for the study, of whom 5,461 were diagnosed with CKD, while 23,382 were not. Patients with CKD exhibited significantly lower DI-GM scores compared to healthy individuals. A negative association between DI-GM and the prevalence of CKD was observed across all models, with the relationship being more pronounced in individuals with DI-GM scores greater than 5 compared to those with scores ≤3. Beneficial components, such as dietary fiber, whole grains, and coffee, were identified as protective factors. Moreover, sex make an effect on this relationship, with stronger effects noted in women.

Conclusion

Higher DI-GM scores correlate with reduced CKD prevalence, and the effect appears to be more pronounced in women than in men. These findings suggest that enhancing gut health through diet may serve as a viable strategy for the prevention and management of CKD, with particular attention to sex-based differences in prevention.

Overview on biomarkers for immune oncology drugs

Although immune checkpoint inhibitors (ICIs) are widely used in clinical oncology, less than half of treated cancer patients derive benefit from this therapy. Both tumor- and host-related variables are implicated in response to ICIs. The predictive value of PD-L1 expression is confined only to several cancer types, so this molecule is not an agnostic biomarker. Highly elevated tumor mutation burden (TMB) caused either by excessive carcinogenic exposure or by a deficiency in DNA repair is a reliable indicator for ICI efficacy, as exemplified by tumors with high-level microsatellite instability (MSI-H). Other potentially relevant tumor-related characteristics include gene expression signatures, pattern of tumor infiltration by immune cells, and, perhaps, some immune-response modifying somatic mutations. Host-related factors have not yet been comprehensively considered in relevant clinical trials. Microbiome composition, markers of systemic inflammation [e.g., neutrophil-to-lymphocyte ratio (NLR)], and human leucocyte antigen (HLA) diversity may influence the efficacy of ICIs. Studies on ICI biomarkers are likely to reveal modifiable tumor or host characteristics, which can be utilized to direct the antitumor immune defense. Examples of the latter approach include tumor priming to immune therapy by cytotoxic drugs and elevation of ICI efficacy by microbiome modification.

Effects of gut microbiota on immune checkpoint inhibitors in multi-cancer and as microbial biomarkers for predicting therapeutic response

BACKGROUND

Gut bacteria are related to immune checkpoint inhibitors (ICIs). However, there is inconsistency in ICI-associated species, while the role of non-bacterial microbes in immunotherapy remains elusive. Here, we evaluated the association of trans-kingdom microbes with ICIs by multi-cohort multi-cancer analyses.

METHODS

We retrieved fecal metagenomes from 1,359 ICI recipients with four different cancers (metastatic melanoma [MM], non-small cell lung carcinoma [NSCLC], renal cell cancer [RCC], and hepatocellular carcinoma) from 12 published datasets. Microbiota composition was analyzed using the Wilcoxon rank test. The performance of microbial biomarkers in predicting ICI response was assessed by random forest. Key responder-associated microbes were functionally examined in vitro and in mice.

FINDINGS

Trans-kingdom gut microbiota (bacteria, eukaryotes, viruses, and archaea) was significantly different between ICI responders and non-responders in multi-cancer. Bacteria (Faecalibacterium prausnitzii, Coprococcus comes) and eukaryotes (Nemania serpens, Hyphopichia pseudoburtonii) were consistently enriched in responders of ≥2 cancer types or from ≥3 cohorts, contrasting with the depleted bacterium Hungatella hathewayi. Responder-associated species in each cancer were revealed, such as F. prausnitzii in MM and 6 species in NSCLC. These signature species influenced ICI efficacy by modulating CD8+ T cell activity in vitro and in mice. Moreover, bacterial and eukaryotic biomarkers showed great performance in predicting ICI response in patients from discovery and two validation cohorts (MM: area under the receiver operating characteristic curve [AUROC] = 72.27%-80.19%; NSCLC: AUROC = 72.70%-87.98%; RCC: AUROC = 83.33%-89.58%).

CONCLUSIONS

This study identified trans-kingdom microbial signatures associated with ICI in multi-cancer and specific cancer types. Trans-kingdom microbial biomarkers are potential predictors of ICI response in patients with cancer.

FUNDING

Funding information is shown in the acknowledgments.

Gut microbiota as a new target for anticancer therapy: from mechanism to means of regulation

In order to decipher the relationship between gut microbiota imbalance and cancer, this paper reviewed the role of intestinal microbiota in anticancer therapy and related mechanisms, discussed the current research status of gut microbiota as a biomarker of cancer, and finally summarized the reasonable means of regulating gut microbiota to assist cancer therapy. Overall, our study reveals that the gut microbiota can serve as a potential target for improving cancer management.