The Role of Gut Microbiota in Tumor Immunotherapy

Engineered inulin-based hybrid biomaterials for augmented immunomodulatory responses

Modified biopolymers that are based on prebiotics have been found to significantly contribute to immunomodulatory events. In recent years, there has been a growing use of modified biomaterials and polymer-functionalized nanomaterials in the treatment of various tumors by activating immune cells. However, the effectiveness of immune cells against tumors is hindered by several biological barriers, which highlights the importance of harnessing prebiotic-based biopolymers to enhance host defenses against cancer, thus advancing cancer prevention strategies. Inulin, in particular, plays a crucial role in activating immune cells and promoting the secretion of cytokines. Therefore, this mini-review aims to emphasize the importance of inulin in immunomodulatory responses, the development of inulin-based hybrid biopolymers, and the role of inulin in enhancing immunity and modifying cell surfaces. Furthermore, we discuss the various approaches of chemical modification for inulin and their potential use in cancer treatment, particularly in the field of cancer immunotherapy.

Adoptive T Cell Therapy in Solid Tumors: State-of-the Art, Current Challenges, and Upcoming Improvements

In solid tumors, three main complementary approaches of adoptive T-cell therapies were successively developed: tumor-infiltrating lymphocytes, chimeric antigen receptor engineered T cells, and high-affinity T-cell receptor engineered T cells. In this review, we summarized rational and main results of these three adoptive T-cell therapies in solid tumors field and gave an overview of encouraging data and their limits. Then, we listed the major remaining challenges (including tumor antigen loss, on-target/off-tumor effect, tumor access difficulties and general/local immunosubversion) and their lines of research. Finally, we gave insight into the ongoing trials in solid tumor.

Oral administration of Manuka honey induces IFNγ-dependent resistance to tumor growth that correlates with beneficial modulation of gut microbiota composition

Background

To investigate the potential of Manuka honey (MH) as an immunomodulatory agent in colorectal cancer (CRC) and dissect the underlying molecular and cellular mechanisms.

Methods

MH was administered orally over a 4 week-period. The effect of MH treatment on microbiota composition was studied using 16S rRNA sequencing of fecal pellets collected before and after treatment. Pretreated mice were implanted with CRC cells and followed for tumor growth. Tumors and lymphoid organs were analyzed by flow cytometry (FACS), immunohistochemistry and qRT-PCR. Efficacy of MH was also assessed in a therapeutic setting, with oral treatment initiated after tumor implantation. We utilized IFNγ-deficient mice to determine the importance of interferon signaling in MH-induced immunomodulation.

Results

Pretreatment with MH enhanced anti-tumor responses leading to suppression of tumor growth. Evidence for enhanced tumor immunogenicity included upregulated MHC class-II on intratumoral macrophages, enhanced MHC class-I expression on tumor cells and increased infiltration of effector T cells into the tumor microenvironment. Importantly, oral MH was also effective in retarding tumor growth when given therapeutically. Transcriptomic analysis of tumor tissue highlighted changes in the expression of various chemokines and inflammatory cytokines that drive the observed changes in tumor immunogenicity. The immunomodulatory capacity of MH was abrogated in IFNγ-deficient mice. Finally, bacterial 16S rRNA sequencing demonstrated that oral MH treatment induced unique changes in gut microbiota that may well underlie the IFN-dependent enhancement in tumor immunogenicity.

Conclusion

Our findings highlight the immunostimulatory properties of MH and demonstrate its potential utilization in cancer prevention and treatment.

Fecal microbiota transplantation: no longer cinderella in tumour immunotherapy

The incidence of cancer has shown a great increase during the past decades and poses tough challenges to cancer treatment. Anti-tumour immunotherapy, represented by immune checkpoint inhibitors (ICIs), possesses favorable remission in unrestricted spectrum of cancer types. However, its efficacy seems to be heterogeneous among accumulating studies. Emerging evidences suggest that gut microbiota can modulate anti-tumour immuno-response and predict clinical prognosis. Therefore, remodeling microbiota characteristics with fecal microbiota transplantation (FMT) may be capable of reinforcing host ICIs performance by regulating immune-tumour cell interactions and altering microbial metabolites, thereby imperceptibly shifting the tumour microenvironment. However, the long-term safety of FMT is under concern, which calls for more rigorous screening. In this review, we examine current experimental and clinical evidences supporting the FMT efficacy in boosting anti-tumour immuno-response and lessening tumour-related complications. Moreover, we discuss the challenges in FMT and propose feasible resolutions, which may offer crucial guidance for future clinical operations.

Clinical potential of microbiota in thyroid cancer therapy

Thyroid cancer is one of the most common tumors of the endocrine system because of its rapid and steady increase in incidence and prevalence. In recent years, a growing number of studies have identified a key role for the gut, thyroid tissue and oral microbiota in the regulation of metabolism and the immune system. A growing body of evidence has conclusively demonstrated that the microbiota influences tumor formation, prevention, diagnosis, and treatment. We provide extensive information in which oral, gut, and thyroid microbiota have an effect on thyroid cancer development in this review. In addition, we thoroughly discuss the various microbiota species, their potential functions, and the underlying mechanisms for thyroid cancer. The microbiome offers a unique opportunity to improve the effectiveness of immunotherapy and radioiodine therapy thyroid cancer by maintaining the right type of microbiota, and holds great promise for improving clinical outcomes and quality of life for thyroid cancer patients.

Microbial Therapy and Breast Cancer Management: Exploring Mechanisms, Clinical Efficacy, and Integration within the One Health Approach

This comprehensive review elucidates the profound relationship between the human microbiome and breast cancer management. Recent findings highlight the significance of microbial alterations in tissue, such as the gut and the breast, and their role in influencing the breast cancer risk, development, progression, and treatment outcomes. We delve into how the gut microbiome can modulate systemic inflammatory responses and estrogen levels, thereby impacting cancer initiation and therapeutic drug efficacy. Furthermore, we explore the unique microbial diversity within breast tissue, indicating potential imbalances brought about by cancer and highlighting specific microbes as promising therapeutic targets. Emphasizing a holistic One Health approach, this review underscores the importance of integrating insights from human, animal, and environmental health to gain a deeper understanding of the complex microbe-cancer interplay. As the field advances, the strategic manipulation of the microbiome and its metabolites presents innovative prospects for the enhancement of cancer diagnostics and therapeutics. However, rigorous clinical trials remain essential to confirm the potential of microbiota-based interventions in breast cancer management.

Microbiome as a biomarker and therapeutic target in pancreatic cancer

Studying the effects of the microbiome on the development of different types of cancer has recently received increasing research attention. In this context, the microbial content of organs of the gastrointestinal tract has been proposed to play a potential role in the development of pancreatic cancer (PC). Proposed mechanisms for the pathogenesis of PC include persistent inflammation caused by microbiota leading to an impairment of antitumor immune surveillance and altered cellular processes in the tumor microenvironment. The limited available diagnostic markers that can currently be used for screening suggest the importance of microbial composition as a non-invasive biomarker that can be used in clinical settings. Samples including saliva, stool, and blood can be analyzed by 16 s rRNA sequencing to determine the relative abundance of specific bacteria. Studies have shown the potentially beneficial effects of prebiotics, probiotics, antibiotics, fecal microbial transplantation, and bacteriophage therapy in altering microbial diversity, and subsequently improving treatment outcomes. In this review, we summarize the potential impact of the microbiome in the pathogenesis of PC, and the role these microorganisms might play as biomarkers in the diagnosis and determining the prognosis of patients. We also discuss novel treatment methods being used to minimize or prevent the progression of dysbiosis by modulating the microbial composition. Emerging evidence is supportive of applying these findings to improve current therapeutic strategies employed in the treatment of PC.

Advances in the role of gut microbiota in the regulation of the tumor microenvironment (Review)

As a protector of human health, the gut microbiota plays an important role in the development of the immune system during childhood, and the regulation of dietary habits, metabolism and immune system during adulthood. Dysregulated gut flora is not pathogenic, but it can weaken the protective effect of the immune system and cause various diseases. The tumor microenvironment is a physiological environment formed during tumor growth, which provides nutrients and growth factors necessary for tumor growth. As an important factor affecting the tumor microenvironment, the intestinal microflora affects the development of tumors through the mechanisms of gut and microflora metabolites, gene toxins and signaling pathways. The present article aimed to review the components and mechanisms of action, clinical applications, and biological targets of gut microbiota in the regulation of the tumor microenvironment. The present review provides novel insights for the future use of intestinal flora, to regulate the tumor microenvironment, to intervene in the occurrence, development, treatment and prognosis of tumors.

Interactions of Nanomaterials with Gut Microbiota and Their Applications in Cancer Therapy

Cancer treatment is a challenge by its incredible complexity. As a key driver and player of cancer, gut microbiota influences the efficacy of cancer treatment. Modalities to manipulate gut microbiota have been reported to enhance antitumor efficacy in some cases. Nanomaterials (NMs) have been comprehensively applied in cancer diagnosis, imaging, and theranostics due to their unique and excellent properties, and their effectiveness is also influenced by gut microbiota. Nanotechnology is capable of targeting and manipulating gut microbiota, which offers massive opportunities to potentiate cancer treatment. Given the complexity of gut microbiota-host interactions, understanding NMs-gut interactions and NMs-gut microbiota interactions are important for applying nanotechnologies towards manipulating gut microbiota in cancer prevention and treatment. In this review, we provide an overview of NMs-gut interactions and NMs-gut microbiota interactions and highlight the influences of gut microbiota on the diagnosis and treatment effects of NMs, further illustrating the potential of nanotechnologies in cancer therapy. Investigation of the influences of NMs on cancer from the perspective of gut microbiota will boost the prospect of nanotechnology intervention of gut microbiota for cancer therapy.

The involvement of Th1 cell differentiation in the anti-tumor effect of purified polysaccharide from Sanghuangporus vaninii in colorectal cancer via multi-omics analysis

Sanghuangporus vaninii is a medicinal mushroom, which has been used as a treatment for various diseases; however, the therapeutic potential and mechanism of action of S. vaninii in colorectal cancer (CRC) remain unknown. Herein, human colon adenocarcinoma cells were used to analyze the anti-CRC effects of the purified polysaccharide of S. vaninii (SVP-A-1) in vitro. In SVP-A-1-treated B6/JGpt-Apc^{em1Cin (Min)}/Gpt male (Apc^Min/+) mice, 16S rRNA sequencing was performed on cecal feces, metabolites were examined in serum, and LC-MS/MS protein detection was performed in colorectal tumors. Protein changes were further confirmed by various biochemical detection methods. Water-soluble SVP-A-1 with a molecular weight of 22.5 kDa was first obtained. SVP-A-1 prevented gut microbiota dysbiosis related to metabolic pathways of L-arginine biosynthesis, increased L-citrulline levels in the serum of Apc^Min/+ mice, mediated L-arginine synthesis, and improved antigen presentation in dendritic cells and activated CD4⁺ T cells; the resulting Th1 cells released IFN-γ and TNF-α to act on tumor cells and promoted the sensitivity of tumor cells to cytotoxic T lymphocytes. In summary, SVP-A-1 exerted anti-CRC effects and has excellent potential for CRC treatment.

Interleukin-35 -producing B cells rescues inflammatory bowel disease in a mouse model via STAT3 phosphorylation and intestinal microbiota modification

Interleukin-35 (IL-35)-producing B cells (IL-35⁺B cells) play an important role in diseases, and the expansion of IL-35⁺ immune cells have been observed in inflammatory bowel disease (IBD). However, how IL-35⁺B cells function and the manner in which they perform their roles remain unclear. In this study, human samples and animal models were used to confirm the expansion of IL-35⁺B cells during IBD. In addition, by using il12a^-/- and ebi3^-/- mice, we demonstrated that the regulatory role of B cells in IBD depends on IL-35. Mechanically, IL-35⁺B cells can promote its own expansion through endocrine actions and depend on the transcription factor signal transducer and activator of transcription 3. Interestingly, we found that the diversity of intestinal microbes and expression of microbial metabolites decreased during IBD. IL-35⁺B cells promote the high expression of indoleacetic acid (IAA), and exogenous metabolite supplementation with IAA can further promote the expansion of IL-35⁺B cells and rescues the disease. This study provides a new concept for the regulatory model of B cells and a new approach for the treatment of IBD.

Gut microbiome in multiple myeloma: Mechanisms of progression and clinical applications

The gut commensal microbes modulate human immunity and metabolism through the production of a large number of metabolites, which act as signaling molecules and substrates of metabolic reactions in a diverse range of biological processes. There is a growing appreciation for the importance of immunometabolic mechanisms of the host-gut microbiota interactions in various malignant tumors. Emerging studies have suggested intestinal microbiota contributes to the progression of multiple myeloma. In this review, we summarized the current understanding of the gut microbiome in MM progression and treatment, and the influence of alterations in gut microbiota on treatment response and treatment-related toxicity and complications in MM patients undergoing hematopoietic stem cell transplantation (HSCT). Furthermore, we discussed the impact of gut microbiota-immune system interactions in tumor immunotherapy, focusing on tumor vaccine immunotherapy, which may be an effective approach to improve anti-myeloma efficacy.

The Crosstalk between Microbiome and Immunotherapeutics: Myth or Reality

The gut microbiome refers to microorganisms and their genetic material influencing local and systemic inflammation. Inflammation is known to contribute to cancer development, progression, and treatment. Evidence suggests that modulating the gut microbiome may affect responses to various cancer therapies. The gut microbiota has been suggested to have an impact on immunotherapy efficacy, especially the currently widely used immune checkpoint inhibitors in various malignancies. Microbial interventions like fecal microbiota transplantation, various probiotics, or even antibiotics can increase or decrease the tumor’s sensitivity to immunotherapy. However, not all tumors react in the same manner, highlighting the tumor microenvironment heterogeneity across tumor types and the influence this has on the crosstalk between the microbiome and therapy outcomes. In this study, we intend to review the association between the gut microbiota and immunotherapy response in cancer patients and the factors regulating this interaction.

Advances in Anti-Cancer Activities of Flavonoids in Scutellariae radix: Perspectives on Mechanism

Despite encouraging progresses in the development of novel therapies, cancer remains the dominant cause of disease-related mortality and has become a leading economic and healthcare burden worldwide. Scutellariae radix (SR, Huangqin in Chinese) is a common herb used in traditional Chinese medicine, with a long history in treating a series of symptoms resulting from cancer, like dysregulated immune response and metabolic abnormalities. As major bioactive ingredients extracted from SR, flavonoids, including baicalein, wogonin, along with their glycosides (baicalin and wogonoside), represent promising pharmacological and anti-tumor activities and deserve extensive research attention. Emerging evidence has made great strides in elucidating the multi-targeting therapeutic mechanisms and key signaling pathways underlying the efficacious potential of flavonoids derived from SR in the field of cancer treatment. In this current review, we aim to summarize the pharmacological actions of flavonoids against various cancers in vivo and in vitro. Moreover, we also make a brief summarization of the endeavor in developing a drug delivery system or structural modification to enhance the bioavailability and biological activities of flavonoid monomers. Taken together, flavonoid components in SR have great potential to be developed as adjuvant or even primary therapies for the clinical management of cancers and have a promising prospect.

Probiotics and live biotherapeutic products aiming at cancer mitigation and patient recover

Molecular biology techniques allowed access to non-culturable microorganisms, while studies using analytical chemistry, as Liquid Chromatography and Tandem Mass Spectrometry, showed the existence of a complex communication system among bacteria, signaled by quorum sensing molecules. These approaches also allowed the understanding of dysbiosis, in which imbalances in the microbiome diversity, caused by antibiotics, environmental toxins and processed foods, lead to the constitution of different diseases, as cancer. Colorectal cancer, for example, can originate by a dysbiosis configuration, which leads to biofilm formation, production of toxic metabolites, DNA damage in intestinal epithelial cells through the secretion of genotoxins, and epigenetic regulation of oncogenes. However, probiotic strains can also act in epigenetic processes, and so be use for recovering important intestinal functions and controlling dysbiosis and cancer mitigation through the metabolism of drugs used in chemotherapy, controlling the proliferation of cancer cells, improving the immune response of the host, regulation of cell differentiation and apoptosis, among others. There are still gaps in studies on the effectiveness of the use of probiotics, therefore omics and analytical chemistry are important approaches to understand the role of bacterial communication, formation of biofilms, and the effects of probiotics and microbiome on chemotherapy. The use of probiotics, prebiotics, synbiotics, and metabiotics should be considered as a complement to other more invasive and hazard therapies, such chemotherapy, surgery, and radiotherapy. The study of potential bacteria for cancer treatment, as the next-generation probiotics and Live Biotherapeutic Products, can have a controlling action in epigenetic processes, enabling the use of these bacteria for the mitigation of specific diseases through changes in the regulation of genes of microbiome and host. Thus, it is possible that a path of medicine in the times to come will be more patient-specific treatments, depending on the environmental, genetic, epigenetic and microbiome characteristics of the host.

Microbiome in cancer: An exploration of carcinogenesis, immune responses and immunotherapy

Cancer is a major disease endangering human health. More and more studies have shown that microorganisms play an extremely important role in the occurrence, development and treatment of tumors. As a very promising tumor treatment strategy, immunotherapy has also been proved to have a great relationship with microorganisms. Here, the authors review the contribution of the microbiota to cancer and the research on its impact on cancer immunotherapy. We also highlight the possible mechanism of their interaction and outlined the potential application of microbiota in tumor immunotherapy.

Interaction of Gut Microbiota with Endocrine Homeostasis and Thyroid Cancer

The gut microbiota plays a crucial role in healthy individuals as well as in patients with thyroid diseases, including thyroid cancer. Although the prognosis of differentiated thyroid cancer is predictable, that of some poorly differentiated, medullary, and anaplastic thyroid cancers remains unpromising. As the interaction between the gut microbiota and thyroid cancer has been gradually revealed in recent years, the thyroid gland, a crucial endocrine organ, is shown to have a complex connection with the body's metabolism and is involved in inflammation, autoimmunity, or cancer progression. Dysbiosis of the gut microbiota and its metabolites can influence changes in hormone levels and susceptibility to thyroid cancer through multiple pathways. In this review, we focus on the interactions of the gut microbiota with thyroid function diseases and thyroid cancer. In addition, we also discuss some potential new strategies for the prevention and treatment of thyroid disease and thyroid cancer. Our aim is to provide some possible clinical applications of gut microbiota markers for early diagnosis, treatment, and postoperative management of thyroid cancer. These findings were used to establish a better multi-disciplinary treatment and prevention management strategy and to individualize the treatment of patients in relation to their gut microbiota composition and pathological characteristics.

Human Microbiota and Immunotherapy in Breast Cancer - A Review of Recent Developments

Breast cancer (BC) is the most common malignancy and the second cause of cancer-specific death in women from high-income countries. Infectious agents are the third most important risk factor for cancer incidence after tobacco and obesity. Dysbiosis emerged as a key player that may influence cancer development, treatment, and prognosis through diverse biological processes. Metastatic BC has a highly variable clinical course, and more recently, immune checkpoint inhibitors (ICIs) have become an emerging therapy in BC. Even with standardised treatment protocols, patients do not respond similarly, reflecting each individual´s heterogeneity, unique BC features, and tumour microenvironment. However, there is insufficient data regarding predictive factors of response to available treatments for BC. The microbiota could be a crucial piece of the puzzle to anticipate better individual BC risk and prognosis, pharmacokinetics, pharmacodynamics, and clinical efficacy. In recent years, it has been shown that gut microbiota may modulate cancer treatments’ efficacy and adverse effects, and it is also apparent that both cancer itself and anticancer therapies interact with gut microbiota bidirectionally. Moreover, it has been proposed that certain gut microbes may protect the host against inappropriate inflammation and modulate the immune response. Future clinical research will determine if microbiota may be a prognostic and predictive factor of response to ICI and/or its side effects. Also, modulation of microbiota can be used to improve outcomes in BC patients. In this review, we discuss the potential implications of metabolomics and pharmacomicrobiomics that might impact BC immunotherapy treatment.