Gallic acid induces T-helper-1-like Treg cells and strengthens immune checkpoint blockade efficacy

Gallic Acid Inhibits the Proliferation and Migration of Ovarian Cancer Cells via Inhibition of the PI3K-AKT Pathway and Promoting M1-Like Macrophage Polarization

Ovarian cancer is one of the leading malignant women tumors that causes higher mortality, and immunotherapy has shown high potential in the treatment of advanced ovarian cancer patients by activating and mobilizing the human immune system, which can improve patient prognosis and survival. Natural compounds are a big resource for screening and finding effective lead compounds to treat diseases. Gallic acid (GA) is a natural organic acid with broad-spectrum antibacterial, antiviral, and antitumor effects. In the current study, we aim to explore the effect of GA on ovarian cancer and its underlying mechanisms. The CCK-8 assay was employed to study its anti-proliferation effect and wound healing, and transwell assay was utilized to test the GA effect on cell migration and invasion. The xenograft tumor model was used to evaluate the GA anticancer effect in vivo. The results demonstrated that GA significantly suppresses the proliferation of ovarian cancer cells both in vitro and in vivo, reduces their migration and invasion capability, and enhances macrophage cytotoxicity in the murine ID8 xenograft tumor microenvironment (TME). The mechanism study demonstrated that its anticancer effect and enhancing immunity is stem from inhibiting the PI3k-AKT pathway. In conclusion, GA plays an anticancer effect via blockage of the PI3K-AKT pathway.

Integrated Glucocorticoids and Traditional Chinese Medicine in a Squamous Lung Cancer Patient with Dermatologic Toxicities Related to Pembrolizumab: A Case Report

The report presents the case of a 70-year-old man with advanced squamous lung cancer who developed dermatologic toxicities after receiving Pembrolizumab-based therapy. During the acute phase, the patient was treated with an integrative treatment of glucocorticosteroids and traditional Chinese medicine (TCM) and achieved superior efficacy. The patient presented with blisters and papules distributed covering 60% of the trunk and extremities, along with more than 90% coverage of the hands and feet, graded as a cutaneous immune-related adverse event (irAE) of 3-4 levels, and accompanied by pruritus, infections, hypercoagulation, hypoproteinemia, and electrolyte disturbance. He was initially on intravenous glucocorticoids synchronized with TCM decoctions for seven days, which effectively intercepted the appearance of fresh cutaneous lesions, with noticeable alleviation of pruritus and other complications. He then began to taper his glucocorticoid dosage with the assistance of TCM. Antihistamines and topicals were used in the first three weeks. As a result, the cutaneous symptoms were well controlled, and he was subsequently transferred for further anti-tumor therapies. In conclusion, integrated glucocorticoids and TCM was used to bring the patient out of the acute phase of high-grade irAE dermatologic toxicity successfully. In this case, the cutaneous symptoms were resolved more rapidly, with earlier glucocorticoid tapering and fewer adverse hormonal effects, without tumor progression.

Advanced RPL19-TRAPKI-seq method reveals mechanism of action of bioactive compounds

Natural products play a crucial role in new drug development, but their druggability is often limited by uncertain molecular targets and insufficient research on mechanisms of action. In this study, we developed a new RPL19-TRAPKI-seq method, combining CRISPR/Cas9 and TRAP technologies, to investigate these mechanisms. We identified and validated seven ribosomal large subunit surface proteins suitable for TRAP, selecting RPL19 for its high enrichment. We successfully established a stable cell line expressing EGFP-RPL19 using CRISPR knock-in and verified its efficiency and specificity in enriching ribosomes and translating mRNA. Integrated with next-generation sequencing, this method allows precise detection of translating mRNA. We validated RPL19-TRAPKI-seq by investigating rapamycin, an mTOR inhibitor, yielding results consistent with previous reports. This optimized TRAP technology provides an accurate representation of translating mRNA, closely reflecting protein expression levels. Furthermore, we investigated SBF-1, a 23-oxa-analog of natural saponin OSW-1 with significant anti-tumor activity but an unclear mechanism. Using RPL19-TRAPKI-seq, we found that SBF-1 exerts its cytotoxic effects on tumor cells by disturbing cellular oxidative phosphorylation. In conclusion, our method has been proven to be a promising tool that can reveal the mechanisms of small molecules with greater accuracy, setting the stage for future exploration of small molecules and advancing the fields of pharmacology and therapeutic development.

Unleashing the Power of immune Checkpoints: A new strategy for enhancing Treg cells depletion to boost antitumor immunity

Regulatory T (Treg) cells, immunosuppressive CD4+ T cells, can impede anti-tumor immunity, complicating cancer treatment. Since their discovery, numerous studies have been dedicated to understand Treg cell biology, with a focus on checkpoint pathways' role in their generation and function. Immune checkpoints, such as PD-1/PD-L1, CTLA-4, TIGIT, TIM-3, and OX40, are pivotal in controlling Treg cell expansion and activity in the tumor microenvironment (TME), affecting their ability to suppress immune responses. This review examines the complex relationship between these checkpoints and Tregs in the TME, and how they influence tumor immunity. We also discuss the therapeutic potential of targeting these checkpoints to enhance anti-tumor immunity, including the use of immune checkpoint blockade (ICB) therapies and novel approaches such as CCR8-targeted therapies. Understanding the interaction between immune checkpoints and Treg cells can lead to more effective immunotherapeutic strategies, such as combining CCR8-targeted therapies with immune checkpoint inhibitors, to improve patient outcomes in cancer treatment.

Improving regulatory T cell-based therapy: insights into post-translational modification regulation

Regulatory T (Treg) cells are pivotal for maintaining immune homeostasis and play essential roles in various diseases, such as autoimmune diseases, graft-versus-host disease (GVHD), tumors, and infectious diseases. Treg cells exert suppressive function via distinct mechanisms, including inhibitory cytokines, granzyme or perforin-mediated cytolysis, metabolic disruption, and suppression of dendritic cells. Forkhead Box P3 (FOXP3), the characteristic transcription factor, is essential for Treg cell function and plasticity. Cumulative evidence has demonstrated that FOXP3 activity and Treg cell function are modulated by a variety of post-translational modifications (PTMs), including ubiquitination, acetylation, phosphorylation, methylation, glycosylation, poly(ADP-ribosyl)ation, and uncharacterized modifications. This review describes Treg cell suppressive mechanisms and summarizes the current evidence on PTM regulation of FOXP3 and Treg cell function. Understanding the regulatory role of PTMs in Treg cell plasticity and function will be helpful in designing therapeutic strategies for autoimmune diseases, GVHD, tumors, and infectious diseases.

The gut microbiome modulate response to immunotherapy in cancer

Gut microbiota have been reported to play an important role in the occurrence and development of malignant tumors. Currently, clinical studies have identified specific gut microbiota and its metabolites associated with efficacy of immunotherapy in multiple types of cancers. Preclinical investigations have elucidated that gut microbiota modulate the antitumor immunity and affect the efficacy of cancer immunotherapy. Certain microbiota and its metabolites may favorably remodel the tumor microenvironment by engaging innate and/or adaptive immune cells. Understanding how the gut microbiome interacts with cancer immunotherapy opens new avenues for improving treatment strategies. Fecal microbial transplants, probiotics, dietary interventions, and other strategies targeting the microbiota have shown promise in preclinical studies to enhance the immunotherapy. Ongoing clinical trials are evaluating these approaches. This review presents the recent advancements in understanding the dynamic interplay among the host immunity, the microbiome, and cancer immunotherapy, as well as strategies for modulating the microbiome, with a view to translating into clinical applications.

Gallic acid enhances GVL effects of T cells without exacerbating GVHD after haematopoietic stem cell transplantation

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is an effective therapy for acute myeloid leukaemia (AML), predominantly due to its potent graft-versus-leukaemia (GVL) effect. However, leukaemia relapse remains a major obstacle to the success of allo-HSCT. In this study, we demonstrated that gallic acid (GA), a natural dietary compound, can enhance T-cell-mediated GVL effects both in vitro and in vivo. GA-treated T cells exhibited increased activation and elevated secretion of cytotoxic cytokines, leading to the apoptosis of AML cells in co-culture systems in vitro. In a non-irradiated leukaemia mouse model, we showed that GA treatment prolonged the survival of leukaemic mice and reduced leukaemia cell infiltration. Further analysis revealed that GA treatment increased T-cell activation and tumour necrosis factor-α secretion. Moreover, integrated transcriptomic and proteomic analyses indicated that GA augments T-cell-mediated GVL effects through the activation of the MAPK and NF-κB pathways. Blocking these pathways individually diminished the protective effect of GA in AML model mice. Importantly, GA administration did not accelerate graft-versus-host disease (GVHD) progression in a mouse model. In conclusion, our study revealed that GA can enhance the GVL effects of T cells without exacerbating GVHD, offering insights into its potential to improve outcomes for patients after HSCT.

Gut microbial metabolites in cancer therapy

The gut microbiota plays a crucial role in maintaining homeostasis and promoting health. A growing number of studies have indicated that gut microbiota can affect cancer development, prognosis, and treatment through their metabolites. By remodeling the tumor microenvironment and regulating tumor immunity, gut microbial metabolites significantly influence the efficacy of anticancer therapies, including chemo-, radio-, and immunotherapy. Several novel therapies that target gut microbial metabolites have shown great promise in cancer models. In this review, we summarize the current research status of gut microbial metabolites in cancer, aiming to provide new directions for future tumor therapy.

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.

Neutrophil extracellular traps: Potential targets for the treatment of rheumatoid arthritis with traditional Chinese medicine and natural products

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Abnormal formation of neutrophil extracellular traps (NETs) at the synovial membrane leads to the release of many inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Elastase, histone H3, and myeloperoxidase, which are carried by NETs, damage the soft tissues of the joints and aggravate the progression of RA. The balance of NET formation coordinates the pro-inflammatory and anti-inflammatory effects and plays a key role in the development of RA. Therefore, when NETs are used as effector targets, highly targeted drugs with fewer side effects can be developed to treat RA without damaging the host immune system. Currently, an increasing number of studies have shown that traditional Chinese medicines and natural products can regulate the formation of NETs through multiple pathways to counteract RA, which shows great potential for the treatment of RA and has a promising future for clinical application. In this article, we review the latest biological progress in understanding NET formation, the mechanism of NETs in RA, and the potential targets or pathways related to the modulation of NET formation by Chinese medicines and natural products. This review provides a relevant basis for the use of Chinese medicines and natural products as natural adjuvants in the treatment of RA.

Optimizing CD8+ T cell-based immunotherapy via metabolic interventions: a comprehensive review of intrinsic and extrinsic modulators

CD8+ T cells are integral to the effective management of cancer and infectious diseases due to their cytotoxic functions. The efficacy of these cells is profoundly influenced by their metabolic state, which regulates their activation, differentiation, and longevity. Accordingly, the modulation of metabolic pathways within CD8+ T cells is crucial for enhancing the effectiveness of T cell-based immunotherapy. Precise metabolic control is paramount in optimizing therapeutic outcomes and minimizing potential toxicities associated with treatment. Importantly, the potential of exogenous metabolites to augment CD8+ T cell responses is critically evaluated, especially through in vivo evidence that underscores their therapeutic promise. This review also addresses current challenges, including the need for precise control of metabolic modulation to avoid adverse effects, the development of targeted delivery systems to ensure efficient metabolite delivery to CD8+ T cells, and the inherent variability of metabolic states among patients that may influence treatment outcomes. Addressing these hurdles will be crucial for the successful integration of metabolic interventions into established immunotherapeutic regimens.

The SUMO Family: Mechanisms and Implications in Thyroid Cancer Pathogenesis and Therapy

(1) Background: Small ubiquitin-like modifiers (SUMOs) are pivotal in post-translational modifications, influencing various cellular processes, such as protein localization, stability, and genome integrity. (2) Methods: This review explores the SUMO family, including its isoforms and catalytic cycle, highlighting their significance in regulating key biological functions in thyroid cancer. We discuss the multifaceted roles of SUMOylation in DNA repair mechanisms, protein stability, and the modulation of receptor activities, particularly in the context of thyroid cancer. (3) Results: The aberrant SUMOylation machinery contributes to tumorigenesis through altered gene expression and immune evasion mechanisms. Furthermore, we examine the therapeutic potential of targeting SUMOylation pathways in thyroid cancer treatment, emphasizing the need for further research to develop effective SUMOylation inhibitors. (4) Conclusions: By understanding the intricate roles of SUMOylation in cancer biology, we can pave the way for innovative therapeutic strategies to improve outcomes for patients with advanced tumors.

Causal effects and metabolites mediators between immune cell and risk of colorectal cancer: a Mendelian randomization study

Objective

The involvement of immune cells in colorectal cancer (CRC) and their interplay with metabolic disorders are yet to be fully elucidated. This study examines how peripheral immune cells, inferred genetically, affect CRC and investigates the intermediary roles of metabolites.

Methods

We employed a two-sample bidirectional Mendelian randomization (MR) approach to assess the causal influence of immune cells on CRC. Additionally, a two-step MR strategy was utilized to pinpoint potential metabolites that mediate this effect. Our analysis incorporated data from genome-wide association studies (GWAS), involving 731 immune cell types, 1,400 metabolites, and CRC outcomes. The primary method of analysis was randomized inverse variance weighting (IVW), supported by MR-Egger, weighted median, simple mode, and weighted mode analyses. Sensitivity checks were conducted using Cochran's Q test, MR-PRESSO test, MR-Egger regression intercept, and leave-one-out analysis.

Results

The study identified 23 immune cell types and 17 metabolites that are causally linked to CRC. Our mediation analysis highlighted that nine metabolites act as intermediaries in the relationship between nine specific immune cells and CRC risk. Notably, The ratios of Adenosine 5'-monophosphate (AMP) to aspartate and Retinol (Vitamin A) to linoleoyl-arachidonoyl-glycerol (18:2 to 20:4) were found to concurrently mediate the promoting effects of Myeloid DC %DC and BAFF-R on B cells in colorectal cancer (CRC). Moreover, iminodiacetate (IDA) was found to mediate the protective effect of CD14+ CD16- monocytes on CRC, contributing 11.8% to this mediation. In contrast, IDA was also seen to decrease the protective effect of IgD+ CD38br %B cells on CRC risk, with a mediation effect proportion of -10.4%.

Conclusion

This study delineates a complex network involving immune cells, metabolites, and CRC, suggesting a multifaceted pathophysiological interaction. The identified causal links and mediation pathways underscore potential therapeutic targets, providing a foundation for interventions aimed at modulating immune responses to manage CRC.

Gallic acid promotes macrophage phagosome acidification and phagolysosome formation by activating NLRP3/mTOR signaling pathway

INTRODUCTION

Gallic acid (GA) has a good therapeutic effect in bacteriological inhibition and plays a variety of functions in maintaining the stability of the immune system. The aim of the present study was to investigate the effect of GA on the bactericidal activity of macrophages against Vibrio vulnificus (Vv).

METHODS

A cell counting kit-8 (CCK-8) assay was carried out to test the cytotoxicity of GA on J774A.1 cells. Concentration of proinflammatory cytokines in J774A.1 cells were evaluated by ELISA. The internalization and degradation of Vv in the phagosomes were observed by transmission electron microscopy (TEM). The phagosome acidification and phagolysosome formation were detected to evaluate the bacteria-clearing function of J774A.1 cells. The bactericidal activity of GA in vivo was also investigated by collecting the survival time of Vv infected mice and observing the inflammatory infiltration of organs.

RESULTS

Our results demonstrated that GA at 50 μM significantly inhibited the proinflammatory cytokines levels, promoted phagosome acidification and phagolysosome formation in J774A.1 cells with Vv infection. This may be related to the activation of NLRP3/mTOR signaling pathway. Additionally, GA treatment improves the survival and bactericidal activity of mice infected with Vv.

CONCLUSIONS

In summary, GA exerts bactericidal activity against Vv infection by regulating the formation and acidification of phagocytic lysosomes in macrophages.

Synthesis of a pH/temperature bi-response gallic acid magnetic imprinted polymer for extracting natural product from Galla chinensis

A pH/temperature bi-responsive gallic acid magnetic imprinted polymer (PTBG-MIP) was synthesized on a Fe3O4@SiO2@KH570 carrier using methacrylic acid (MAA), p-Vinylphenylboronic acid (p-VPBA), and N-isopropyl-acrylamide (NIPAAm) as complex functional monomers. The density functional theory (DFT) was employed to optimize the molar ratio of multi-functional monomers-template complex, which proved to be an effective tool for predicting complex configuration based on electrostatic potential (ESP) analysis and the lowest binding energy. DFT calculation and analysis determined the optimized molar ratio of 2:1:1:1 for GA-MAA-NIPAAm-p-VPBA, which showed good agreement with experimental results. The PTBG-MIP-4 obtained under the optimized conditions exhibited high pH- and temperature- dependence in rebinding the template, displaying a maximum adsorption capacity (Qe) of 62.26 mg g-1 and a highest selection factor (α) of 5.217. Additionally, the PTBG-MIP-4 exhibited exceptional physicochemical properties encompassing magnetization characteristics, morphology, surface sites distribution, and adsorption performance. The application efficiency of this imprinted composite in the extraction and purification of gallic acid from Galla chinensis was remarkably demonstrated.

Fragile Treg cells: Traitors in immune homeostasis?

Regulatory T (Treg) cells play a key role in maintaining immune tolerance and tissue homeostasis. However, in some disease microenvironments, Treg cells exhibit fragility, which manifests as preserved FoxP3 expression accompanied by inflammation and loss of immunosuppression. Fragile Treg cells are formatively, phenotypically and functionally diverse in various diseases, further complicating the role of Treg cells in the immunotherapeutic response and offering novel targets for disease treatment by modulating specific Treg subsets. In this review, we summarize findings on fragile Treg cells to provide a framework for characterizing the formation and role of fragile Treg cells in different diseases, and we discuss how this information may guide the development of more specific Treg-targeted immunotherapies.

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Gallic acid suppresses the progression of clear cell renal cell carcinoma through inducing autophagy via the PI3K/Akt/Atg16L1 signaling pathway

Clear cell renal cell carcinoma (ccRCC), the most common type of renal cell carcinoma (RCC), is not sensitive to traditional radiotherapy and chemotherapy. The polyphenolic compound Gallic acid (GA) can be naturally found in a variety of fruits, vegetables and plants. Autophagy, an intracellular catabolic process, regulates the lysosomal degradation of organelles and portions in cytoplasm. It was reported that autophagy and GA could affect the development of several cancers. Therefore, the aim of the present study was to evaluate the effects of GA on ccRCC development and clarify the role of autophagy in this process. In the present study, the effects of GA on the proliferation, migration and invasion of ccRCC cells were investigated in vitro by Cell Counting Kit‑8, colony formation, flow cytometry, wound healing and Transwell migration assays, respectively. Additionally, the effects of GA on ccRCC growth and metastasis were evaluated using hematoxylin‑eosin and immunohistochemical staining in vivo. Moreover, it was sought to explore the underlying molecular mechanisms using transmission electron microscopy, western blotting and reverse transcription‑quantitative PCR analyses. In the present study, it was revealed that GA had a more potent viability inhibitory effect on ccRCC cells (786‑O and ACHN) than the effect on normal renal tubular epithelial cell (HK‑2), which demonstrated that GA selectively inhibits the viability of cancer cells. Furthermore, it was identified that GA dose‑dependently inhibited the proliferation, migration and invasion of ccRCC cells in vitro and in vivo. It was demonstrated that GA promoted the release of autophagy markers, which played a role in regulating the PI3K/Akt/Atg16L1 signaling pathway. All the aforementioned data provided evidence for the great potential of GA in the treatment of ccRCC.

Microbial metabolites affect tumor progression, immunity and therapy prediction by reshaping the tumor microenvironment (Review)

Several studies have indicated that the gut microbiome and tumor microbiota may affect tumors. Emerging metabolomics research illustrates the need to examine the variations in microbial metabolite composition between patients with cancer and healthy individuals. Microbial metabolites can impact the progression of tumors and the immune response by influencing a number of mechanisms, including modulation of the immune system, cancer or immune‑related signaling pathways, epigenetic modification of proteins and DNA damage. Microbial metabolites can also alleviate side effects and drug resistance during chemotherapy and immunotherapy, while effectively activating the immune system to exert tumor immunotherapy. Nevertheless, the impact of microbial metabolites on tumor immunity can be both beneficial and harmful, potentially influenced by the concentration of the metabolites or the specific cancer type. The present review summarizes the roles of various microbial metabolites in different solid tumors, alongside their influence on tumor immunity and treatment. Additionally, clinical trials evaluating the therapeutic effects of microbial metabolites or related microbes on patients with cancer have been listed. In summary, studying microbial metabolites, which play a crucial role in the interaction between the microbiota and tumors, could lead to the identification of new supplementary treatments for cancer. This has the potential to improve the effectiveness of cancer treatment and enhance patient prognosis.

Ethnopharmacology, chemical composition and functions of Cymbopogon citratus

Cymbopogon citratus in the gramineous family, also known as lemongrass (LG), is a perennial herb. LG, a drug and food homologous medicine, has a widely recorded medicinal value and food applications. To date, 158 LG compounds have been reported, including terpenoids, flavonoids, phenolic acids. Pharmacological and clinical studies have indicated that LG has antibacterial, neuroprotective, hypoglycemic, hypotensive, anti-inflammatory, and anti-tumor effects. This article reviews LG in ethnopharmacology, chemical composition, pharmacology, food, medicine, and daily chemical applications to provide a basis for the subsequent development of food and medicine.

Pan-cancer analysis of T-cell proliferation regulatory genes as potential immunotherapeutic targets

T cells are the key to killing tumor cells. However, the exact mechanism of their role in cancer is not fully understood. Therefore, a comprehensive understanding of the role of T-cell proliferation regulatory genes in tumors is needed. In our study, we investigated the expression levels of genes controlling T-cell proliferation, their impact on prognosis, and their genetic variations. Additionally, we explored their associations with TMB, MSI, ESTIMATEScore, ImmuneScore, StromalScore, and immune cell infiltration. We examined the role of these genes in cancer-related pathways using GSEA. Furthermore, we calculated their activity levels across various types of cancer. Drug analysis was also conducted targeting these genes. Single-cell analysis, LASSO Cox model construction, and prognosis analysis were performed. We observed distinct expression patterns of T-cell proliferation regulatory genes across different malignant tumors. Their abnormal expression may be caused by CNA and DNA methylation. In certain cancers, they also showed complex associations with TMB and MSI. Moreover, in many tumors, they exhibited significant positive correlations with ESTIMATEScores, ImmuneScore, and StromalScore. Additionally, in most tumors, their GSVA scores were significantly positively correlated with various T-cell subtypes. GSEA analysis revealed their involvement in multiple immune pathways. Furthermore, we found that model scores were associated with patient prognosis and related to tumor malignancy progression. T-cell proliferation regulatory genes are closely associated with the tumor immune microenvironment (TIM), especially T cells. Targeting them may be an essential approach for cancer immunotherapy.

Comprehensive analysis of the relationship between ubiquitin-specific protease 21 (USP21) and prognosis, tumor microenvironment infiltration, and therapy response in colorectal cancer

BACKGROUND

Ubiquitin-specific proteases family is crucial to host immunity against pathogens. However, the correlations between USP21 and immunosurveillance and immunotherapy for colorectal cancer (CRC) have not been reported.

METHODS

The differential expression of USP21 between CRC tissues and normal tissues was analyzed using multiple public databases. Validation was carried out in clinical samples through qRT-PCR and IHC. The correlation between USP21 and the prognosis, as well as clinical pathological characteristics of CRC patients, was investigated. Moreover, cell models were established to assess the influence of USP21 on CRC growth and progression, employing CCK-8 assays, colony formation assays, and wound-healing assays. Subsequently, gene set variation analysis (GSVA) was used to explore the potential biological functions of USP21 in CRC. The study also examined the impact of USP21 on cytokine levels and immune cell infiltration in the tumor microenvironment (TME). Finally, the effect of USP21 on the response to immunotherapy and chemotherapy in CRC was analyzed.

RESULTS

The expression of USP21 was significantly upregulated in CRC. High USP21 is correlated with poor prognosis in CRC patients and facilitates the proliferation and migration capacities of CRC cells. GSVA indicated an association between low USP21 and immune activation. Moreover, low USP21 was linked to an immune-activated TME, characterized by high immune cell infiltration. Importantly, CRC with low USP21 exhibited higher tumor mutational burden, high PD-L1 expression, and better responsiveness to immunotherapy and chemotherapeutic drugs.

CONCLUSION

This study revealed the role of USP21 in TME, response to therapy, and clinical prognosis in CRC, which provided novel insights for the therapeutic application in CRC.

Progress in the Regulation of Immune Cells in the Tumor Microenvironment by Bioactive Compounds of Traditional Chinese Medicine

The tumor microenvironment (TME) can aid tumor cells in evading surveillance and clearance by immune cells, creating an internal environment conducive to tumor cell growth. Consequently, there is a growing focus on researching anti-tumor immunity through the regulation of immune cells within the TME. Various bioactive compounds in traditional Chinese medicine (TCM) are known to alter the immune balance by modulating the activity of immune cells in the TME. In turn, this enhances the body's immune response, thus promoting the effective elimination of tumor cells. This study aims to consolidate recent findings on the regulatory effects of bioactive compounds from TCM on immune cells within the TME. The bioactive compounds of TCM regulate the TME by modulating macrophages, dendritic cells, natural killer cells and T lymphocytes and their immune checkpoints. TCM has a long history of having been used in clinical practice in China. Chinese medicine contains various chemical constituents, including alkaloids, polysaccharides, saponins and flavonoids. These components activate various immune cells, thereby improving systemic functions and maintaining overall health. In this review, recent progress in relation to bioactive compounds derived from TCM will be covered, including TCM alkaloids, polysaccharides, saponins and flavonoids. This study provides a basis for further in-depth research and development in the field of anti-tumor immunomodulation using bioactive compounds from TCM.

The effects of metabolism on the immune microenvironment in colorectal cancer

Colorectal cancer (CRC) is a malignancy that is widely prevalent worldwide. Due to its unsatisfactory treatment outcome and extremely poor prognosis, many studies on the molecular mechanisms and pathological mechanisms of CRC have been published in recent years. The tumor microenvironment (TME) is an extremely important feature of tumorigenesis and one of the hallmarks of tumor development. Metabolic reprogramming is currently a hot topic in tumor research, and studies on this topic have provided important insights into CRC development. In particular, metabolic reprogramming in cancer causes changes in the composition of energy and nutrients in the TME. Furthermore, it can alter the complex crosstalk between immune cells and associated immune factors, such as associated macrophages and T cells, which play important immune roles in the TME, in turn affecting the immune escape of tumors by altering immune surveillance. In this review, we summarize several metabolism-related processes affecting the immune microenvironment of CRC tumors. Our results showed that the immune microenvironment is regulated by metabolic reprogramming and influences the development of CRC.

Programmed Death Ligand 1 Regulatory Crosstalk with Ubiquitination and Deubiquitination: Implications in Cancer Immunotherapy

Programmed death ligand 1 (PD-L1) plays a pivotal role in cancer immune evasion and is a critical target for cancer immunotherapy. This review focuses on the regulation of PD-L1 through the dynamic processes of ubiquitination and deubiquitination, which are crucial for its stability and function. Here, we explored the intricate mechanisms involving various E3 ubiquitin ligases and deubiquitinating enzymes (DUBs) that modulate PD-L1 expression in cancer cells. Specific ligases are discussed in detail, highlighting their roles in tagging PD-L1 for degradation. Furthermore, we discuss the actions of DUBs that stabilize PD-L1 by removing ubiquitin chains. The interplay of these enzymes not only dictates PD-L1 levels but also influences cancer progression and patient response to immunotherapies. Furthermore, we discuss the therapeutic implications of targeting these regulatory pathways and propose novel strategies to enhance the efficacy of PD-L1/PD-1-based therapies. Our review underscores the complexity of PD-L1 regulation and its significant impact on the tumor microenvironment and immunotherapy outcomes.

Forsythia suspensa polyphenols regulate macrophage M1 polarization to alleviate intestinal inflammation in mice

BACKGROUND

Inflammatory bowel disease (IBD) was a chronic intestinal disease related to autoimmunity, and its pathogenesis was complex. Forsythia suspensa (F. suspensa) had good anti-inflammatory and antioxidant effects. The active component polyphenols had significant effects in the treatment of intestinal inflammation. Researches had found that polarization, pyroptosis and apoptosis of macrophages can drive the occurrence and development of colitis.

PURPOSE

In this study, we examined whether F. suspensa polyphenols (FPP) mitigated DSS-induced colitis, and explored its potential mechanisms.

METHODS

The potential targets of F. suspensa in intestinal inflammation were predicted through network pharmacology. Using LPS and IFN-γ induced macrophage M1 polarization in J774A.1 cells. Macrophage polarization was detected through RT-qPCR, flow cytometry and ELISA. Ulcerative colitis (UC) in mice was induced by 2.5% DSS for 7 days, and then oral administrated different doses of FPP for another 7 days. Then we assessed the body weight, diarrhea, bleeding in stool, colon length, cytokines of serum and pathology of colon. The effects of FPP on the gut microbiota in mice also tested and evaluated.

RESULTS

Our results showed that the main active ingredient of F. suspensa in protecting intestinal inflammation were polyphenols and F. suspensa was multi-targeted in the treatment of intestinal inflammation. FPP inhibited M1 polarization and polarizes towards M2 in J774A.1 cells. FPP inhibited pyroptosis and apoptosis to exert anti-inflammatory effects. FPP had a good protective effect on DSS induced UC in mice. In unison, FPP inhibited M1 polarization, apoptosis, and pyroptosis in UC mice. FPP regulated intestinal homeostasis in mice with UC by improving the gut microbiota and enhancing the intestinal metabolites short-chain fatty acid (SCFAs).

CONCLUSIONS

These data indicated that FPP may alleviate UC by inhibiting M1 polarization in mice. Collectively, these findings suggest that the reduction of colitis by FPP may related to macrophage polarization, pyroptosis and apoptosis.

The Effectiveness of Traditional Chinese Medicine in Treating Malignancies via Regulatory Cell Death Pathways and the Tumor Immune Microenvironment: A Review of Recent Advances

Traditional Chinese Medicine (TCM) has achieved high clinical efficacy in treating malignancies in recent years and is thus gradually becoming an important therapy for patients with advanced tumor for its benefits in reducing side effects and improving patients' immune status. However, it has not been internationally recognized for cancer treatment because TCM's anti-tumor mechanism is not fully elucidated, limiting its clinical application and international promotion. This review traced the mechanism of the TCM-mediated tumor cell death pathway and its effect on remodeling the tumor immune microenvironment, its direct impact on the microenvironment, its anti-tumor effect in combination with immunotherapy, and the current status of clinical application of TCM on tumor treatment. TCM can induce tumor cell death in many regulatory cell death (RCD) pathways, including apoptosis, autophagy, pyroptosis, necroptosis, and ferroptosis. In addition, TCM-induced cell death could increase the immune cells' infiltration with an anti-tumor effect in the tumor tissue and elevate the proportion of these cells in the spleen or peripheral blood, enhancing the anti-tumor capacity of the tumor-bearing host. Moreover, TCM can directly affect immune function by increasing the population or activating the sub-type immune cells with an anti-tumor role. It was concluded that TCM could induce a pan-tumor death modality, remodeling the local TIME differently. It can also improve the systemic immune status of tumor-bearing hosts. This review aims to establish a theoretical basis for the clinical application of TCM in tumor treatment and to provide a reference for TCM's potential in combination with immunotherapy in cancer treatment.

Comprehensive analysis of the role of ubiquitin-specific peptidases in colorectal cancer: A systematic review

BACKGROUND

Colorectal cancer (CRC) is the third most frequent and the second most fatal cancer. The search for more effective drugs to treat this disease is ongoing. A better understanding of the mechanisms of CRC development and progression may reveal new therapeutic strategies. Ubiquitin-specific peptidases (USPs), the largest group of the deubiquitinase protein family, have long been implicated in various cancers. There have been numerous studies on the role of USPs in CRC; however, a comprehensive view of this role is lacking.

AIM

To provide a systematic review of the studies investigating the roles and functions of USPs in CRC.

METHODS

We systematically queried the MEDLINE (via PubMed), Scopus, and Web of Science databases.

RESULTS

Our study highlights the pivotal role of various USPs in several processes implicated in CRC: Regulation of the cell cycle, apoptosis, cancer stemness, epithelial-mesenchymal transition, metastasis, DNA repair, and drug resistance. The findings of this study suggest that USPs have great potential as drug targets and noninvasive biomarkers in CRC. The dysregulation of USPs in CRC contributes to drug resistance through multiple mechanisms.

CONCLUSION

Targeting specific USPs involved in drug resistance pathways could provide a novel therapeutic strategy for overcoming resistance to current treatment regimens in CRC.

Targeting T regulatory (Treg) cells in immunotherapy-resistant cancers

Primary or secondary (i.e., acquired) resistance is a common occurrence in cancer patients and is often associated with high numbers of T regulatory (Treg) cells (CD4+CD25+FOXP3+). The approval of ipilimumab and the development of similar pharmacological agents targeting cell surface proteins on Treg cells demonstrates that such intervention may overcome resistance in cancer patients. Hence, the clinical development and subsequent approval of Cytotoxic T Lymphocyte Antigen-4 (CTLA-4) targeting agents can serve as a prototype for similar agents. Such new agents aspire to be highly specific and have a reduced toxicity profile while increasing effector T cell function or effector T/T regulatory (Teff/Treg) ratio. While clinical development with large molecules has shown the greatest advancement, small molecule inhibitors that target immunomodulation are increasingly entering early clinical investigation. These new small molecule inhibitors often target specific intracellular signaling pathways [e.g., phosphoinositide-3-kinase delta (PI3K-δ)] that play an important role in regulating the function of Treg cells. This review will summarize the lessons currently applied to develop novel clinical agents that target Treg cells.

FOXP3+ regulatory T cell perturbation mediated by the IFNγ-STAT1-IFITM3 feedback loop is essential for anti-tumor immunity

Targeting tumor-infiltrating regulatory T cells (Tregs) is an efficient way to evoke an anti-tumor immune response. However, how Tregs maintain their fragility and stability remains largely unknown. IFITM3 and STAT1 are interferon-induced genes that play a positive role in the progression of tumors. Here, we showed that IFITM3-deficient Tregs blunted tumor growth by strengthening the tumor-killing response and displayed the Th1-like Treg phenotype with higher secretion of IFNγ. Mechanistically, depletion of IFITM3 enhances the translation and phosphorylation of STAT1. On the contrary, the decreased IFITM3 expression in STAT1-deficient Tregs indicates that STAT1 conversely regulates the expression of IFITM3 to form a feedback loop. Blocking the inflammatory cytokine IFNγ or directly depleting STAT1-IFITM3 axis phenocopies the restored suppressive function of tumor-infiltrating Tregs in the tumor model. Overall, our study demonstrates that the perturbation of tumor-infiltrating Tregs through the IFNγ-IFITM3-STAT1 feedback loop is essential for anti-tumor immunity and constitutes a targetable vulnerability of cancer immunotherapy.

Modulatory Role of Phytochemicals/Natural Products in Cancer Immunotherapy

Immunotherapy is a newly emerging and effective approach to treating cancer. However, there are many challenges associated with using checkpoint inhibitors in this treatment strategy. The component of the tumor microenvironment plays a crucial role in antitumor immune response, regulating tumor immune surveillance and immunological evasion. Natural products/phytochemicals can modulate the tumor microenvironment and function as immunomodulatory agents. In clinical settings, there is a strong need to develop synergistic combination regimens using natural products that can effectively enhance the therapeutic benefits of immune checkpoint inhibitors relative to their effectiveness as single therapies. The review discusses immunotherapy, its side effects, and a summary of evidence suggesting the use of natural products to modulate immune checkpoint pathways.

Polyphenol Supplementation Enhances the Efficacy of PD-1/PD-L1 Inhibitors Against Cancer: A Meta-Analysis of Animal Studies

BACKGROUND

This study performed a meta-analysis to evaluate the combined effects of polyphenols and anti-programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) inhibitors.

METHODS

Relevant studies were collected from electronic databases. Standardized mean differences (SMDs) or hazard ratio (HR) was calculated by Stata 15.0 software.

RESULTS

Sixteen preclinical studies were included. The overall meta-analysis showed that, compared to anti-PD-1/PD-L1 alone, polyphenol combined therapy significantly reduced the tumor volume (SMD = -3.28), weight (SMD = -2.18), number (SMD = -2.17), and prolonged the survival (HR = 0.45) of mice (all P < 0.001). Pooled analysis of mechanism studies indicated polyphenol combined therapy could increase the number of cytotoxic CD8+ T cells (SMD = 3.88; P < 0.001), IFN-γ+ CD8+ T cells (SMD = 2.38; P < 0.001), decrease the number of myeloid-derived suppressor cells (SMD = -2.52; P = 0.044) and Treg cells (SMD = -4.00; P = 0.004) and suppress PD-L1 expression in tumors (SMD = -13.41; P < 0.001). Subgroup analyses demonstrated curcuminoids, flavonoids, and stilbene changed the tumor volume, the percentage of CD8+ T cells, IFN-γ+CD8+ T cells, and PD-L1 expression.

CONCLUSION

Polyphenol supplementation may be a promising combined strategy for patients with poor response to anti-PD-1/PD-L1 monotherapy.

Emerging role of deubiquitination modifications of programmed death-ligand 1 in cancer immunotherapy

Immune evasion is essential for carcinogenesis and cancer progression. Programmed death-ligand 1 (PD-L1), a critical immune checkpoint molecule, interacts with programmed death receptor-1 (PD-1) on immune cells to suppress anti-tumor immune responses. In the past decade, antibodies targeting PD-1/PD-L1 have tremendously altered cancer treatment paradigms. Post-translational modifications have been reported as key regulators of PD-L1 expression. Among these modifications, ubiquitination and deubiquitination are reversible processes that dynamically control protein degradation and stabilization. Deubiquitinating enzymes (DUBs) are responsible for deubiquitination and have emerged as crucial players in tumor growth, progression, and immune evasion. Recently, studies have highlighted the participation of DUBs in deubiquitinating PD-L1 and modulating its expression. Here, we review the recent developments in deubiquitination modifications of PD-L1 and focus on the underlying mechanisms and effects on anti-tumor immunity.

Traditional Chinese medicine inhibits PD-1/PD-L1 axis to sensitize cancer immunotherapy: a literature review

The Programmed death-1 (PD-1) and its programmed death-ligand 1 (PD-L1) comprise the PD-1/PD-L1 axis and maintain tumor immune evasion. Cancer immunotherapy based on anti-PD-1/PD-L1 antibodies is the most promising anti-tumor treatment available but is currently facing the thorny problem of unsatisfactory outcomes. Traditional Chinese Medicine (TCM), with its rich heritage of Chinese medicine monomers, herbal formulas, and physical therapies like acupuncture, moxibustion, and catgut implantation, is a multi-component and multi-target system of medicine known for enhancing immunity and preventing the spread of disease. TCM is often used as an adjuvant therapy for cancer in clinical practices, and recent studies have demonstrated the synergistic effects of combining TCM with cancer immunotherapy. In this review, we examined the PD-1/PD-L1 axis and its role in tumor immune escape while exploring how TCM therapies can modulate the PD-1/PD-L1 axis to improve the efficacy of cancer immunotherapy. Our findings suggest that TCM therapy can enhance cancer immunotherapy by reducing the expression of PD-1 and PD-L1, regulating T-cell function, improving the tumor immune microenvironment, and regulating intestinal flora. We hope this review may serve as a valuable resource for future studies on the sensitization of immune checkpoint inhibitors (ICIs) therapy.

The impact of microbially modified metabolites associated with obesity and bariatric surgery on antitumor immunity

Obesity is strongly associated with the occurrence and development of many types of cancers. Patients with obesity and cancer present with features of a disordered gut microbiota and metabolism, which may inhibit the physiological immune response to tumors and possibly damage immune cells in the tumor microenvironment. In recent years, bariatric surgery has become increasingly common and is recognized as an effective strategy for long-term weight loss; furthermore, bariatric surgery can induce favorable changes in the gut microbiota. Some studies have found that microbial metabolites, such as short-chain fatty acids (SCFAs), inosine bile acids and spermidine, play an important role in anticancer immunity. In this review, we describe the changes in microbial metabolites initiated by bariatric surgery and discuss the effects of these metabolites on anticancer immunity. This review attempts to clarify the relationship between alterations in microbial metabolites due to bariatric surgery and the effectiveness of cancer treatment. Furthermore, this review seeks to provide strategies for the development of microbial metabolites mimicking the benefits of bariatric surgery with the aim of improving therapeutic outcomes in cancer patients who have not received bariatric surgery.

Research progress of traditional Chinese medicine as sensitizer in reversing chemoresistance of colorectal cancer

In recent years, the incidences and mortalities from colorectal cancer (CRC) have been increasing; therefore, there is an urgent need to discover newer drugs that enhance drug sensitivity and reverse drug tolerance in CRC treatment. With this view, the current study focuses on understanding the mechanism of CRC chemoresistance to the drug as well as exploring the potential of different traditional Chinese medicine (TCM) in restoring the sensitivity of CRC to chemotherapeutic drugs. Moreover, the mechanism involved in restoring sensitivity, such as by acting on the target of traditional chemical drugs, assisting drug activation, increasing intracellular accumulation of anticancer drugs, improving tumor microenvironment, relieving immunosuppression, and erasing reversible modification like methylation, have been thoroughly discussed. Furthermore, the effect of TCM along with anticancer drugs in reducing toxicity, increasing efficiency, mediating new ways of cell death, and effectively blocking the drug resistance mechanism has been studied. We aimed to explore the potential of TCM as a sensitizer of anti-CRC drugs for the development of a new natural, less-toxic, and highly effective sensitizer to CRC chemoresistance.

Acertannin prevents azoxymethane/dextran sulfate sodium-induced colon cancer growth by inhibiting the colonic expression of interleukin-1β, monocyte chemoattractant protein-1, cyclooxygenase-2, and thymocyte selection-associated high mobility group box proteins (TOX)/TOX2 in C57BL/6J mice

Colon cancer was the second leading cause of cancer-related death in 2019. We herein investigated the effects of acertannin containing Acer species on azoxymethane (AOM)/dextran sulfate sodium (DDS)-induced colon cancer growth and changes in the colonic levels of interleukin (IL)-1β, monocyte chemoattractant protein (MCP)-1, IL-10, and programmed cell death-1 (PD-1). Colorectal carcinogenesis was induced by an intraperitoneal injection of AOM (10 mg/kg) on days 0 and 27. Mice were given 1% (w/v) DSS drinking water ad libitum on days 7-14, 32-33, and 35-38. Acertannin (30 and 100 mg/kg) was orally administered on days 1-16, discontinued for 11 days (days 16-26), and then administered again on days 27-41. The colonic levels of cytokines, a chemokine, and PD-1 were measured using the respective ELISA kits. The number and area of tumors in mice treated with acertannin (100 mg/kg) decreased by 53.9 and 63.1%, respectively. Furthermore, the colonic levels of IL-1β, MCP-1, IL-10, and PD-1 showed reductions of 57.3, 62.9, 62.8, and 100%, respectively, while the numbers of cyclooxygenase-2 (COX-2)-, thymocyte selection-associated high mobility group box proteins (TOX)/TOX2-, PD-1-, and signal transducer and activator of transcription 3 (STAT3) phosphorylation-positive numbers decreased by 79.6, 77.9, 93.8, and 100%, respectively. In conclusion, the inhibitory effects of acertannin on AOM/DSS-induced colon tumor growth appear to be associated with reductions in the colonic levels of IL-1β, MCP-1, IL-10, and PD-1 through the down-regulated expression of COX-2 and TOX/TOX2 in the tumor microenvironment.

FOXP3+ regulatory T cells and the immune escape in solid tumours

FOXP3+ regulatory T (Treg) cells play critical roles in establishing the immunosuppressive tumour microenvironment, which is achieved and dynamically maintained with the contribution of various stromal and immune cell subsets. However, the dynamics of non-lymphoid FOXP3+ Treg cells and the mutual regulation of Treg cells and other cell types in solid tumour microenvironment remains largely unclear. In this review, we summarize the latest findings on the dynamic connections and reciprocal regulations of non-lymphoid Treg cell subsets in accordance with well-established and new emerging hallmarks of cancer, especially on the immune escape of tumour cells in solid tumours. Our comprehension of the interplay between FOXP3+ Treg cells and key hallmarks of cancer may provide new insights into the development of next-generation engineered T cell-based immune treatments for solid tumours.