Cancer-associated fibroblasts impair the cytotoxic function of NK cells in gastric cancer by inducing ferroptosis via iron regulation

Exosome-mediated ferroptosis in the tumor microenvironment: from molecular mechanisms to clinical application

Ferroptosis in the tumor microenvironment (TME) plays a crucial role in the development, metastasis, immune escape, and drug resistance of various types of cancer. A better understanding of ferroptosis in the TME could illuminate novel aspects of this process and promote the development of targeted therapies. Compelling evidence indicates that exosomes are key mediators in regulating the TME. In this respect, it is now understood that exosomes can deliver biologically functional molecules to recipient cells, influencing cancer progression by reprogramming the metabolism of cancer cells and their surrounding stromal cells through ferroptosis. In this review, we focus on the role of exosomes in the TME and describe how they contribute to tumor reprogramming, immunosuppression, and the formation of pre-metastatic niches through ferroptosis. In addition, we highlight exosome-mediated ferroptosis as a potential target for cancer therapy and discuss strategies employing exosomes in ferroptosis treatment. Finally, we outline the current applications and challenges of targeted exosome-mediated ferroptosis therapy in tumor immunotherapy and chemotherapy. Our aim is to advance research on the link between exosomes and ferroptosis in the TME, and we pose questions to guide future studies in this area.

Lipotoxicity, lipid peroxidation and ferroptosis: a dilemma in cancer therapy

The vulnerability of tumor cells to lipid peroxidation, driven by redox imbalance and lipid overabundance within the tumor microenvironment (TME), has become a focal point for novel antitumor strategies. Ferroptosis, a form of regulated cell death predicated on lipid peroxidation, is emerging as a promising approach. Beyond their role in directly eliminating tumor cells, lipid peroxidation and its products, such as 4-hydroxynonenal (HNE), exert an additional influence by damaging DNA and shaping an environment conducive to tumor growth and metastasis. This process polarizes macrophages towards a pro-inflammatory phenotype, dampens the antigen-presenting capacity of dendritic cells (DCs), and undermines the cytotoxic functions of T and NK cells. Furthermore, it transforms neutrophils into pro-tumorigenic polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs). The lipid peroxidation of stroma cells also contributes to tumor progression. Although advanced nanotherapies have shown the ability to target tumor cells precisely, they often overlook the nuanced effects of lipid peroxidation products. In this review, we highlight a synergistic mechanism in which lipid peroxidation products and ferroptosis contribute to an immunosuppressive state that is temporally distinct from cell death. This insight broadens our understanding of ferroptosis-derived immunosuppression, encompassing all types of immune cells within the TME. This review aims to catalyze further research in this underexplored area, emphasizing the potential of lipid peroxidation products to hinder the clinical translation of ferroptosis-based therapies.

Bidirectional Mendelian randomization and potential mechanistic insights into the causal relationship between gut microbiota and malignant mesothelioma

Malignant mesothelioma (MM) is a rare but aggressive cancer originating from mesothelial cells, which presents significant challenges to patients' physical and psychological well-being. The gut-lung axis underscores the connection between gut microbiota and respiratory diseases, with emerging evidence suggesting a strong association between gut microbiota and the development of MM. In this study, we conducted a two-sample Mendelian randomization (MR) analysis to investigate the potential causal relationship between gut microbiota and MM, while also exploring the underlying mechanisms through bioinformatics approaches. Gut microbiota summary data were obtained from the MiBioGen consortium, while MM data were sourced from the FinnGen R11 dataset. Causality was examined using the inverse variance weighted method as the primary analysis. Additional methods, including the weighted median, simple mode, MR-Egger, and weighted mode, were also employed. The robustness of the findings was validated through sensitivity analyses, and reverse causality was considered to further strengthen the MR results. Moreover, bioinformatics analyses were conducted on genetic loci associated with both gut microbiota and MM to explore potential underlying mechanisms. Our study suggests that genetically predicted increases in class.Bacilli, family.Rikenellaceae, genus.Clostridium innocuum group, and order.Lactobacillales were suggestively associated with a higher risk of MM, whereas increases in genus.Ruminococcaceae UCG004, genus.Flavonifractor, phylum.Firmicutes, genus.Anaerofilum, genus.Clostridium sensu stricto 1, and genus.Lactobacillus appeared to confer protective effects. Bioinformatics analysis indicated that differentially expressed genes near loci associated with gut microbiota might affect MM by modulating pathways and the tumor microenvironment. The results of this study point to a potential genetic predisposition linking gut microbiota to MM. Further experimental validation is crucial to confirm these candidate microbes, establish causality, and elucidate the underlying mechanisms.

Lidocaine Modulates Cytokine Production and Reprograms the Tumor Immune Microenvironment to Enhance Anti-Tumor Immune Responses in Gastric Cancer

Lidocaine, a local anesthetic, has been shown to modulate immune responses. This study examines its effects on cytokine production in peripheral blood mononuclear cells (PBMCs) from healthy donors and tumor-infiltrating immune cells (TIICs) from gastric cancer patients. PBMCs from healthy donors and TIICs from gastric cancer patients were treated with lidocaine. Cytokine production was assessed using flow cytometry and cytokine assays, with a focus on IFN-γ, IL-12, IL-10, TGF-β, and IL-35 levels. Cytotoxicity against primary gastric cancer cells (PGCCs) was also evaluated. Lidocaine inhibited IFN-γ production in CD8+ PBMCs and IL-12 in CD14+ PBMCs while increasing anti-inflammatory cytokines (IL-10, TGF-β, IL-35) in CD4+CD25+ and CD14+ cells. In TIICs, lidocaine enhanced IFN-γ and IL-12 production in CD8+ and CD14+ cells while reducing IL-10, TGF-β, and IL-35 levels, promoting an M1-like phenotype in macrophages. Mechanistically, lidocaine enhanced IFN-γ production in sorted CD8+ TIICs through G-protein-coupled receptor (GPCR) signaling and increased IL-12 production in sorted CD14+ TIICs via the toll-like receptor 4 (TLR4) signaling pathway. Lidocaine also increased IFN-γ production and cytotoxicity in CD8+ TIICs via NF-κB activation. Importantly, lidocaine did not affect the viability of PBMCs, TIICs, or PGCCs at concentrations up to 1.5 mM. Lidocaine reprogrammed the tumor immune microenvironment, enhancing anti-tumor immune responses, suggesting its potential to modulate immune functions in gastric cancer.

Functional Characterization of the Hephaestin Variant D568H Provides Novel Mechanistic Insights on Iron-Dependent Asbestos-Induced Carcinogenesis

A local disruption of iron homeostasis leading to oxidative stress is considered one of the main mechanisms of asbestos-related genotoxicity. Another aspect contributing to the risk of developing pathological consequences upon asbestos exposure is individual genetic factors. In a previous study, we identified a coding SNP in the hephaestin gene (HEPH) that protects against developing asbestos-related thoracic cancer. Heph is a ferroxidase that promotes iron export in concert with the permease ferroportin (Fpn1). Here, we performed an in-depth functional characterization of the HephD568H variant to gain insights into the molecular basis of its protective activity. We showed that HephD568H forms a complex with Fpn1 and possesses full ferroxidase activity. Although HephD568H is more efficiently recruited to the plasma membrane, it is impaired in binding iron-deficient Tfn, whose interaction with wild-type (WT) ferroxidase emerged as a novel mechanism to perceive brain iron needs. Heph is expressed in the human lung by pericytes and fibroblasts, and lung pericytes were shown to respond to iron demand by upregulating the iron exporter pair. These results extend the paradigm of local iron regulation discovered at the blood-brain barrier to the pulmonary vasculature. Furthermore, they establish a mechanistic link between changes in iron sensing and the risk of developing asbestos-related malignancies.

Regulation of cancer-associated fibroblasts for enhanced cancer immunotherapy using advanced functional nanomedicines: an updated review

The tumor microenvironment (TME) is a complex and dynamic ecosystem that plays a critical role in cancer progression. It comprises various cell types, including immune cells, tumor cells, and stromal cells. Among these, cancer-associated fibroblasts (CAFs) represent a heterogeneous population with diverse origins, phenotypes, and functions. Activated CAFs secrete multiple factors that promote tumor growth, migration, angiogenesis, and contribute to chemoresistance. Additionally, CAFs secrete extracellular matrix (ECM) components, such as collagen, which form a physical barrier that hinders the penetration of chemotherapeutic and immunotherapeutic agents. This ECM also influences immune cell infiltration, impeding their ability to effectively target tumor cells. As a result, modulating the activity of CAFs has emerged as a promising strategy to enhance the efficacy of tumor immunotherapy. Nano-delivery systems, constructed from various nanomaterials with high targeting specificity and biocompatibility, offer a compelling approach to deliver therapeutic agents or immunomodulatory factors directly to CAFs. This modulation can alter CAF function, reduce their tumor-promoting effects, and thereby improve the outcomes of immunotherapy. This review provides an in-depth exploration of the origins, functions, and interactions of CAFs within the TME, particularly in the context of immune suppression. Furthermore, it discusses the potential applications of functional nanocarrifers in modulating CAFs and enhancing the effectiveness of tumor immunotherapy, highlighting the significant progress and potential of nanotechnology in this area.

Ferroptosis in Pulmonary Disease and Lung Cancer: Molecular Mechanisms, Crosstalk Regulation, and Therapeutic Strategies

Ferroptosis is a distinct form of iron-dependent programmed cell death characterized primarily by intracellular iron accumulation and lipid peroxidation. Multiple cellular processes, including amino acid metabolism, iron metabolism, lipid metabolism, various signaling pathways, and autophagy, have been demonstrated to influence the induction and progression of ferroptosis. Recent investigations have elucidated that ferroptosis plays a crucial role in the pathogenesis of various pulmonary disorders, including lung injury, chronic obstructive pulmonary disease, pulmonary fibrosis, and asthma. Ferroptosis is increasingly recognized as a promising novel strategy for cancer treatment. Various immune cells within the tumor microenvironment, including CD8+ T cells, macrophages, regulatory T cells, natural killer cells, and dendritic cells, have been shown to induce ferroptosis in tumor cells and modulate the process through the regulation of iron and lipid metabolism pathways. Conversely, ferroptosis can reciprocally alter the metabolic environment, leading to the activation or inhibition of immune cell functions, thereby modulating immune responses. This paper reviews the molecular mechanism of ferroptosis and describes the tumor immune microenvironment, discusses the connection between ferroptosis and the tumor microenvironment in lung cancer and pulmonary diseases, and discusses the development prospect of their interaction in the treatment of lung cancer and pulmonary diseases.

Iron metabolism and the tumor microenvironment: A new perspective on cancer intervention and therapy (Review)

Iron metabolism plays a crucial role in the tumor microenvironment, influencing various aspects of cancer cell biology and tumor progression. This review discusses the regulatory mechanisms of iron metabolism within the tumor microenvironment and highlights how tumor cells and associated stromal cells manage iron uptake, accumulation and regulation. The sources of iron within tumors and the biological importance of ferroptosis in cancer were explored, focusing on its mechanisms, biological effects and, in particular, its tumor‑suppressive properties. Furthermore, the protective strategies employed by cancer cells to evade ferroptosis were examined. This review also delves into the intricate relationship between iron metabolism and immune modulation within the tumor microenvironment, detailing the impact on tumor‑associated immune cells and immune evasion. The interplay between ferroptosis and immunotherapy is discussed and potential strategies to enhance cancer immunotherapy by modulating iron metabolism are presented. Finally, the current ferroptosis‑based cancer therapeutic approaches were summarized and future directions for therapies that target iron metabolism were proposed.

Versatile Nanomaterials That Interfere with Ferroptosis in the Tumor Microenvironment

Ferroptosis is a type of iron-dependent programmed cell death characterized by a depletion of glutathione. Although generally less harmful to normal cells, in tumor cells, the high demand for iron ions provides conditions conducive to ferroptosis. In this review, we provide an overview of recent progress in research on the regulation of ferroptosis in tumor cells, summarizing and assessing the current state, trends, and applications of nanomaterials in the regulation of ferroptosis in tumor cells. Given the advantages of nanomaterials in terms of targeting, safety, improved drug efficacy, and reduced side effects, these materials are considered to have potential therapeutic value in modulating ferroptosis in tumor cells via different mechanisms. In this respect, we describe methods for modifying the regulation of iron ions and interfering with glutathione activity and lipid peroxidation. The development of nanomaterials that can be applied to induce or inhibit ferroptosis is anticipated to provide new therapeutic options for the treatment of a diverse range of diseases.

What is the Impact of Endothelial-to-Mesenchymal Transition in Solid Tumours: A Qualitative Systematic Review and Quantitative Meta-Analysis

Endothelial-to-mesenchymal transition (EndMT) has gained increasing recognition as a crucial mechanism in the progression of solid cancers, influencing tumour heterogeneity, metastasis, and resistance to therapy. However, despite its growing importance, EndMT remains insufficiently studied within the cancer research landscape. In this study, we conduct a systematic review, adhered to the 2020 PRISMA guidelines, of the existing literature on EndMT in solid tumours, examining its functional roles, key biomarkers, underlying mechanisms, experimental models, and potential as a target for therapeutic intervention. Our objective was to identify critical areas where further research is needed. In addition, we performed a meta-analysis to evaluate the variability in the expression of EndMT-related markers and their potential links to patient prognosis. To this aim, literature searches were conducted in major databases including PubMed, Scopus, and Web of Science, covering studies published up to June 2024. The risk of bias of selected articles was evaluated using the OHAT tool, for the in vitro experiments and the SYRCLE tool for studies using animal models. Out of an initial pool of 1,197 articles, 54 studies were selected for data extraction by two independent reviewers. Selected studies were identified according to specific inclusion/exclusion criteria applied through distinct stages like "title and abstract screening", "full text article review" and "article bibliography screening". Our analysis confirms that EndMT is a key contributor to tumour progression and metastasis, but several aspects remain poorly understood, particularly regarding the induction of EndMT in specific cancer types, its role in lymphatic endothelial cells, and its interactions with other stromal elements. We observed substantial heterogeneity in the biomarkers associated with EndMT, as well as variations in the endothelial cell types studied, the functional outcomes, and the molecular mechanisms involved. Our meta-analysis revealed significant variability in the expression of EndMT biomarkers, with notable correlations between changes in the expression of specific genes and patient outcomes, particularly in lung cancer. In conclusion, it is essential for future research to focus on identifying the specific cancer and stromal cell types implicated in EndMT and to standardize endothelial cell models and protocols used for inducing EndMT. Investigating EndMT alongside well-established processes, such as epithelial-to-mesenchymal transition (EMT), and exploring its relationship with cancer-associated fibroblasts (CAFs) may provide valuable insights into its role in tumour biology and its impact on therapy resistance.

Exerkines: Potential regulators of ferroptosis

Ferroptosis is a programmed cell death, and its mechanism involves multiple metabolic pathways, such as iron and lipid metabolism, and redox homeostasis. Exerkines are important mediators that optimize cellular homeostasis and maintain physiological health during exercise stimulation. This article comprehensively examines the mechanisms and regulatory networks for governing ferroptosis and summarizes the impact of exercise and exerkines on ferroptosis under varying load intensities and disease contexts. Notably, despite its significant efficacy and minimal side effects, the therapeutic and prognostic potential of exercise in ferroptosis-related diseases remains largely unexplored. This article, by summarizing recent progresses in the regulation of exerkines-mediated ferroptosis, could further uncover the preventive or alleviative mechanisms of some diseases upon exercise interventions, which will be beneficial to design exercise interventional strategies for alleviating disease progression through the regulation of ferroptosis.

Clinical significance of the tumor microenvironment on immune tolerance in gastric cancer

In the realm of oncology, the tumor microenvironment (TME)-comprising extracellular matrix components, immune cells, fibroblasts, and endothelial cells-plays a pivotal role in tumorigenesis, progression, and response to therapeutic interventions. Initially, the TME exhibits tumor-suppressive properties that can inhibit malignant transformation. However, as the tumor progresses, various factors induce immune tolerance, resulting in TME behaving in a state that promotes tumor growth and metastasis in later stages. This state of immunosuppression is crucial as it enables TME to change from a role of killing tumor cells to a role of promoting tumor progression. Gastric cancer is a common malignant tumor of the gastrointestinal tract with an alarmingly high mortality rate. While chemotherapy has historically been the cornerstone of treatment, its efficacy in prolonging survival remains limited. The emergence of immunotherapy has opened new therapeutic pathways, yet the challenge of immune tolerance driven by the gastric cancer microenvironment complicates these efforts. This review aims to elucidate the intricate role of the TME in mediating immune tolerance in gastric cancer and to spotlight innovative strategies and clinical trials designed to enhance the efficacy of immunotherapeutic approaches. By providing a comprehensive theoretical framework, this review seeks to advance the understanding and application of immunotherapy in the treatment of gastric cancer, ultimately contributing to improved patient outcomes.

HDAC3: A Multifaceted Modulator in Immunotherapy Sensitization

Histone deacetylase 3 (HDAC3) has emerged as a critical epigenetic regulator in tumor progression and immune modulation, positioning it as a promising target for enhancing cancer immunotherapy. This work comprehensively explores HDAC3's multifaceted roles, focusing on its regulation of key immune-modulatory pathways such as cGAS-STING, ferroptosis, and the Nrf2/HO-1 axis. These pathways are central to tumor immune evasion, antigen presentation, and immune cell activation. Additionally, the distinct effects of HDAC3 on various immune cell types-including its role in enhancing T cell activation, restoring NK cell cytotoxicity, promoting dendritic cell maturation, and modulating macrophage polarization-are thoroughly examined. These findings underscore HDAC3's capacity to reshape the tumor immune microenvironment, converting immunologically "cold tumors" into "hot tumors" and thereby increasing their responsiveness to immunotherapy. The therapeutic potential of HDAC3 inhibitors is highlighted, both as standalone agents and in combination with immune checkpoint inhibitors, to overcome resistance and improve treatment efficacy. Innovative strategies, such as the development of selective HDAC3 inhibitors, advanced nano-delivery systems, and integration with photodynamic or photothermal therapies, are proposed to enhance treatment precision and minimize toxicity. By addressing challenges such as toxicity, patient heterogeneity, and resistance mechanisms, this study provides a forward-looking perspective on the clinical application of HDAC3 inhibitors. It highlights its significant potential in personalized cancer immunotherapy, paving the way for more effective treatments and improved outcomes for cancer patients.

Ferroptosis contributes to immunosuppression

As a novel form of cell death, ferroptosis is mainly regulated by the accumulation of soluble iron ions in the cytoplasm and the production of lipid peroxides and is closely associated with several diseases, including acute kidney injury, ischemic reperfusion injury, neurodegenerative diseases, and cancer. The term "immunosuppression" refers to various factors that can directly harm immune cells' structure and function and affect the synthesis, release, and biological activity of immune molecules, leading to the insufficient response of the immune system to antigen production, failure to successfully resist the invasion of foreign pathogens, and even organ damage and metabolic disorders. An immunosuppressive phase commonly occurs in the progression of many ferroptosis-related diseases, and ferroptosis can directly inhibit immune cell function. However, the relationship between ferroptosis and immunosuppression has not yet been published due to their complicated interactions in various diseases. Therefore, this review deeply discusses the contribution of ferroptosis to immunosuppression in specific cases. In addition to offering new therapeutic targets for ferroptosis-related diseases, the findings will help clarify the issues on how ferroptosis contributes to immunosuppression.

Mast cells: key players in digestive system tumors and their interactions with immune cells

Mast cells (MCs) are critical components of both innate and adaptive immune processes. They play a significant role in protecting human health and in the pathophysiology of various illnesses, including allergies, cardiovascular diseases and autoimmune diseases. Recent studies in tumor-related research have demonstrated that mast cells exert a substantial influence on tumor cell behavior and the tumor microenvironment, exhibiting both pro- and anti-tumor effects. Specifically, mast cells not only secrete mediators related to pro-tumor function such as trypsin-like enzymes, chymotrypsin, vascular endothelial cell growth factor and histamine, but also mediators related to anti-tumor progression such as cystatin C and IL-17F. This dual role of mast cells renders them an under-recognized but very promising target for tumor immunotherapy. Digestive system tumors, characterized by high morbidity and associated mortality rates globally, are increasingly recognized as a significant healthcare burden. This paper examines the influence of mast cell-derived mediators on the development of tumors in the digestive system. It also explores the prognostic significance of mast cells in patients with various gastrointestinal cancers at different stages of the disease. Additionally, the article investigates the interactions between mast cells and immune cells, as well as the potential relationships among intratumoral bacteria, immune cells, and mast cell within digestive system microenvironment. The aim is to propose new strategies for the immunotherapy of digestive system tumors by targeting mast cells.

In-Depth Examination of TPBG as a New Predictive Indicator for Gastric Cancer

Trophoblast glycoprotein (TPBG) plays a significant part in the growth of specific cancers, yet its connection to gastric cancer (GC) remains uncertain. This research seeks to analyse the fluctuation in TPBG levels in GC and evaluate how TPBG expression relates to the prognosis of GC patients. TPBG expression in GC and normal gastric tissues was investigated in The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database, further extracting the immunohistochemistry images from HPA database and validating by Western blot. The connection between TPBG and GC patients' survival rates was investigated by Kaplan-Meier and COX regression analysis. Genes related to TPBG were enriched using GO and KEGG data. In vitro and in vivo tumour models were utilised to evaluate the function of TPBG in GC. Western blot analysis was performed to detect the expression of PI3K/AKT signalling pathway proteins following TPBG knockdown. Immune infiltration was analysed using the CIBERSOFT and ssGSEA methods. The association between TPBG and immune cells that infiltrate tumours was evaluated through the utilisation of GSVA. TPBG expression increased in several tumour tissues (including GC) more than in adjacent noncancerous tissues. Elevated TPBG level predicted worse outcomes, such as poorer overall survival, pathological stage, and therapy response in GC. Enrichment analysis primarily focused on biological processes like the organisation of external encapsulating structures, extracellular structure, and collagen metabolism. Biological experiments further demonstrated that TPBG knockdown successfully inhibits the progression, migration, and invasion of GC cells. Western blot analysis revealed that TPBG knockdown inhibits the PI3K/AKT signalling pathway. Furthermore, TPBG is associated with the infiltration of immune cells in GC, which correlates with the expression of macrophage cells. There is a positive relationship between TPBG and malignant behaviour of GC tissues and cells, suggesting that TPBG can be useful for diagnosing and prognosing GC.

Recent advances in crosstalk between immune cells and cancer cells with ferroptosis

Ferroptosis, a regulated form of cell death distinct from apoptosis and necrosis. Key hallmarks include iron-dependent lipid peroxidation, glutathione depletion, and intracellular iron accumulation, all of which are counteracted by specific cellular defenses. However, the immunosuppressive effects of ferroptosis induction in cancer immunotherapy remain unresolved. This review summarizes the recent advancements in ferroptosis research, focusing on its defensive mechanisms. It analyzes how ferroptosis affects both cancer and immune cells, highlighting its potential inhibitory effects on anti-tumor immunity and possible promotion of pro-tumor immune responses. Finally, this review briefly introduces case studies that combined ferroptosis induction with immunotherapy, offering novel perspectives for cancer treatment.

Opposite expression of NCOA4 in glioblastoma tissues and cell lines

Recent research has found that ferroptosis is the most prevalent type of programmed cell death in glioma tissues and is associated with malignant progression, poor prognosis, and exacerbated immune suppression in glioblastoma (GBM). In recent years, nuclear receptor coactivator 4 (NCOA4) has been identified as a key protein in ferroptosis, but its expression in GBM tissues remains unclear. We observed an intriguing phenomenon where the expression pattern of NCOA4 was opposite in GBM tissues compared to three GBM cell lines (U87-MG, U251, and LN229), with NCOA4 expression being elevated in brain tissue but decreased in the GBM cells. This observation was further confirmed through bioinformatics analysis and experiments. Based on this finding, we hypothesize that immune cells in GBM tissues may exhibit more pronounced signs of iron depletion compared to tumor cells, which could contribute to the therapeutic resistance of GBM. The increase in NCOA4 observed in tumor tissues does not necessarily reflect increased ferroptosis in tumor cells but might indicate increased ferroptosis in non-tumor cells. This point should be considered when evaluating the efficacy of inducing ferroptosis via NCOA4 in GBM research. This observation could potentially impact the proposed strategy of inducing iron depletion as a treatment for GBM. We recognize the importance of this finding for guiding future GBM research and believe it warrants further investigation. This phenomenon may also be present in other types of tumors.

Tumor Metabolic Reprogramming and Ferroptosis: The Impact of Glucose, Protein, and Lipid Metabolism

Ferroptosis, a novel form of cell death discovered in recent years, is typically accompanied by significant iron accumulation and lipid peroxidation during the process. This article systematically elucidates how tumor metabolic reprogramming affects the ferroptosis process in tumor cells. The paper outlines the basic concepts and physiological significance of tumor metabolic reprogramming and ferroptosis, and delves into the specific regulatory mechanisms of glucose metabolism, protein metabolism, and lipid metabolism on ferroptosis. We also explore how complex metabolic changes in the tumor microenvironment further influence the response of tumor cells to ferroptosis. Glucose metabolism modulates ferroptosis sensitivity by influencing intracellular energetic status and redox balance; protein metabolism, involving amino acid metabolism and protein synthesis, plays a crucial role in the initiation and progression of ferroptosis; and the relationship between lipid metabolism and ferroptosis primarily manifests in the generation and elimination of lipid peroxides. This review aims to provide a new perspective on how tumor cells regulate ferroptosis through metabolic reprogramming, with the ultimate goal of offering a theoretical basis for developing novel therapeutic strategies targeting tumor metabolism and ferroptosis.

Infection of Helicobacter pylori contributes to the progression of gastric cancer through ferroptosis

Helicobacter pylori (H. pylori) is a gram-negative pathogen that colonizes gastric epithelial cells, and its chronic infection is the primary risk factor for the development of gastric cancer (GC). Ferroptosis is an iron-dependent form of cell death characterized by intracellular lipid peroxide accumulation and reactive oxygen species (ROS) imbalance. There is evidence suggesting that pathogens can manipulate ferroptosis to facilitate their replication, transmission, and pathogenesis. However, the interaction between ferroptosis and H. pylori infection requires further elucidation. We reviewed the mechanism of ferroptosis and found that H. pylori virulence factors such as cytotoxin-associated gene A (CagA), vacuolating cytotoxin A (VacA), neutrophil-activating protein A (NapA), superoxide dismutase B (SodB), γ-glutamyl transpeptidase (gGT), lipopolysaccharide (LPS), and outer inflammatory protein A (OipA) affected glutathione (GSH), ROS, and lipid oxidation to regulate ferroptosis. It also affected the progression of GC by regulating ferroptosis-related indicators through abnormal gene expression after H. pylori infected gastric mucosa cells. Finally, we discuss the potential application value of ferroptosis inducers, inhibitors and other drugs in treating H. pylori-infected GC patients while acknowledging that their interactions are still not fully understood.

Novel immunotherapeutic approaches in gastric cancer

Gastric cancer is a malignant tumor that ranks third in cancer-related deaths worldwide. Early-stage gastric cancer can often be effectively managed through surgical resection. However, the majority of cases are diagnosed in advanced stages, where outcomes with conventional radiotherapy and chemotherapy remain unsatisfactory. Immunotherapy offers a novel approach to treating molecularly heterogeneous gastric cancer by modifying the immunosuppressive tumor microenvironment. Immune checkpoint inhibitors and adoptive cell therapy are regarded as promising modalities in cancer immunotherapy. Food and Drug Administration-approved programmed death-receptor inhibitors, such as pembrolizumab, in combination with chemotherapy, have significantly extended overall survival in gastric cancer patients and is recommended as a first-line treatment. Despite challenges in solid tumor applications, adoptive cell therapy has demonstrated efficacy against various targets in gastric cancer treatment. Among these approaches, chimeric antigen receptor-T cell therapy research is the most widely explored and chimeric antigen receptor-T cell therapy targeting claudin18.2 has shown acceptable safety and robust anti-tumor capabilities. However, these advancements primarily remain in preclinical stages and further investigation should be made to promote their clinical application. This review summarizes the latest research on immune checkpoint inhibitors and adoptive cell therapy and their limitations, as well as the role of nanoparticles in enhancing immunotherapy.

Therapeutic efficacy of ferroptosis in the treatment of colorectal cancer (Review)

Colorectal cancer (CRC) is the third most common malignancy worldwide, and the second leading cause of cancer-associated mortality. The incidence and mortality rates of CRC remain high, posing a significant threat to humans and overall quality of life. Current therapeutic strategies, such as surgery and chemotherapy, are limited due to disease recurrence, chemotherapeutic drug resistance and toxicity. Thus, research is focused on the development of novel treatment approaches. In 2012, ferroptosis was identified as a form of regulated cell death that is iron-dependent and driven by lipid peroxidation. Notably, therapies targeting ferroptosis exhibit potential in the treatment of disease; however, their role in CRC treatment remains controversial. The present study aimed to systematically review the mechanisms and signaling pathways of ferroptosis in CRC, and the specific role within the tumor microenvironment. Moreover, the present study aimed to review the role of ferroptosis in drug resistance, offering novel perspectives for the diagnosis and treatment of CRC.

Ferroptosis and the tumor microenvironment

Ferroptosis is a type of regulated cell death characterized by its non-apoptotic, iron-dependent and oxidative nature. Since its discovery in 2012, extensive research has demonstrated its pivotal roles in tumorigenesis, metastasis and cancer therapy. The tumor microenvironment (TME) is a complex ecosystem comprising cancer cells, non-cancer cells, extracellular matrix, metabolites and cytokines. Recent studies have underscored a new paradigm in which non-cancer cells in the TME, such as immune and stromal cells, also play significant roles in regulating tumor progression and therapeutic resistance typically through complicated crosstalk with cancer cells. Notably, this crosstalk in the TME were partially mediated through ferrotopsis-related mechanisms. This review provides a comprehensive and systematic summary of the current findings concerning the roles of ferroptosis in the TME and how ferroptosis-mediated TME reprogramming impacts cancer therapeutic resistance and progression. Additionally, this review outlines various ferroptosis-related therapeutic strategies aimed at targeting the TME.

Bioactive polysaccharides mediate ferroptosis to modulate tumor immunotherapy

Polysaccharides from diverse origins exhibit notable bioactivities, particularly their capacity to exert antitumor and immune-enhancing effects. Concurrently, ferroptosis emerges as a distinctive form of regulated cell death characterized by iron-dependent lipid peroxidation, potentially influencing the demise of specific tumor cells and organismal homeostasis. Recent scholarly attention has increasingly focused on utilizing polysaccharides to modulate tumor cell ferroptosis and manipulate cellular immune responses. This article provides an in-depth analysis of contemporary research concerning using polysaccharides to augment antitumor immunity and combat malignancies. Central to our discourse is examining the pivotal role of polysaccharides in mediating ferroptosis, bolstering immune surveillance, and elucidating the interplay between polysaccharides and antitumor immunity. Furthermore, a comprehensive synthesis of the multifaceted roles of polysaccharides in antitumor and immunomodulatory contexts is provided. Recent advances in understanding how polysaccharides enhance immune function by inducing ferroptosis cell death are explained. Lastly, unresolved inquiries are outlined, and potential avenues for future research are proposed, focusing on the translational applications of polysaccharides in antitumor immunotherapy.

The Role of Iron in Intestinal Mucus: Perspectives from Both the Host and Gut Microbiota

Although research on the role of iron in host immunity has a history spanning decades, it is only relatively recently that attention has been directed toward the biological effects of iron on the intestinal mucus layer, prompted by an evolving understanding of the role of this material in immune defense. The mucus layer, secreted by intestinal goblet cells, covers the intestinal epithelium, and given its unique location, interactions between the host and gut microbiota, as well as among constituent microbiota, occur frequently within the mucus layer. Iron, as an essential nutrient for the vast majority of life forms, regulates immune responses from both the host and microbial perspectives. In this review, we summarize the iron metabolism of both the host and gut microbiota and describe how iron contributes to intestinal mucosal homeostasis via the intestinal mucus layer with respect to both host and constituent gut microbiota. The findings described herein offer a new perspective on iron-mediated intestinal mucosal barrier function.

Progress in research of ferroptosis in gastrointestinal tumors

Ferroptosis is a non-apoptotic and oxidation-damaged regulated cell death caused by iron accumulation, lipid peroxidation, and subsequent plasma membrane rupture. Ferroptosis is the main cause of tissue damage caused by iron overload and lipid peroxidation. With the deepening of the research in recent years, the understanding of the occurrence and treatment of tumors has made a major breakthrough, which brings new strategies for anti-cancer treatment. This paper reviews the relationship between ferroptosis and gastrointestinal tumors, the research of ferroptosis in cancer prevention and treatment, and the role of ferroptosis in the prevention and treatment of gastrointestinal tumors.

PPIC-labeled CAFs: Key players in neoadjuvant chemotherapy resistance for gastric cancer

BACKGROUND

Gastric cancer (GC) is the fourth leading cause of cancer deaths, with advanced cases having a median survival of less than one year. Neoadjuvant chemotherapy (NCT) is vital but faces drug resistance issues, partly due to cancer-associated fibroblasts (CAFs). Yet, specific CAF subpopulations contributing to resistance are poorly understood.

METHODS

Differentially expressed genes (DEGs) between chemosensitive and resistant GC patients were identified using GEO2R. Single-cell sequencing (scRNA-seq) identified CAF-related genes. Immunohistochemistry verified key genes in NCT-treated GC samples, analyzing their correlation with tumor regression grade (TRG) and clinicopathological characteristics.

RESULTS

PPIC as a gene highly expressed in CAFs was closely associated with NCT resistance in gastric cancer. Immunohistochemistry results revealed positivity for the expression of cyclophilin C (CypC), encoded by PPIC, in the 5-fluorouracil and cisplatin NCT resistant and -sensitive groups of gastric cancer patients at rates of 69.7 % (76/109) and 43.6 % (24/55), respectively (p < 0.001). The high expression of CypC in CAFs was positively correlated to tumor size (p = 0.025), T stage (p = 0.004), TNM stage (p = 0.004), and vascular invasion (p = 0.027). In cancer cells the expression of CypC was associated with OS (p = 0.026). However, in CAFs, CypC expression was not related to OS (p = 0.671).

CONCLUSIONS

PPIC-labeled CAF subgroups are related to NCT resistance and poor prognosis in GC and they may cause drug resistance through signaling pathways such as glucose metabolism and extracellular matrix remodeling. However, the exact mechanism behind the involvement of PPIC-labeled CAF in drug resistance of GC requires further study.

The use of organoids in creating immune microenvironments and treating gynecological tumors

Owing to patient-derived tumor tissues and cells, significant advances have been made in personalized cancer treatment and precision medicine, with cancer stem cell-derived three-dimensional tumor organoids serving as crucial in vitro models that accurately replicate the structural, phenotypic, and genetic characteristics of tumors. However, despite their extensive use in drug testing, genome editing, and transplantation for facilitating personalized treatment approaches in clinical practice, the inadequate capacity of these organoids to effectively model immune cells and stromal components within the tumor microenvironment limits their potential. Additionally, effective clinical immunotherapy has led the tumor immune microenvironment to garner considerable attention, increasing the demand for simulating patient-specific tumor-immune interactions. Consequently, co-culture techniques integrating tumor organoids with immune cells and tumor microenvironment constituents have been developed to expand the possibilities for personalized drug response investigations, with recent advancements enhancing the understanding of the strengths, limitations, and applicability of the co-culture approach. Herein, the recent advancements in the field of tumor organoids have been comprehensively reviewed, specifically highlighting the tumor organoid co-culture-related developments with various immune cell models and their implications for clinical research. Furthermore, this review delineates the current state of research and application of organoid models regarding the therapeutic approaches and related challenges for gynecological tumors. This study may provide a theoretical basis for further research on the use of patient-derived organoids in tumor immunity, drug development, and precision medicine.

Proliferation capability of natural killer cells upon cytokines stimulation correlated negatively with serum lactate dehydrogenase level in coronary artery disease patients

Background

Natural killer (NK) cells are proposed to participate in coronary artery disease (CAD) development. However, little is known about how CAD patients' NK cells respond to different stimulatory factors in terms of proliferation capability.

Methods and results

Twenty-nine CAD patients' peripheral blood NK cells were isolated and individually treated with IL-2, IL-12, IL-15, IL-18, IL-21, cortisone acetate, hydrocortisone, or ascorbic acid for 36 hours, followed by cell cycle analysis using flow cytometry. The ratio of S and G2/M phase cell number to total cell number was defined as a proliferation index (PrI) and used for proliferative capability indication. The results showed that these eight factors resulted in different life cycle changes in the 29 NK cell samples. Remarkably, 28 out of 29 NK cell samples showed an obvious increase in PrI upon ascorbic acid treatment. The serum lactate dehydrogenase (LDH) level of the 29 CAD patients was measured. The results showed a negative correlation between serum LDH level and the CAD patients' NK cell PrI upon stimulation of interleukins, but not the non-interleukin stimulators. Consistently, a retrospective analysis of 46 CAD patients and 32 healthy donors showed that the circulating NK cell number negatively correlated with the serum LDH level in CAD patients. Unexpectedly, addition of LDH to NK cells significantly enhanced the production of IFN-γ, IL-10 and TNF-α, suggesting a strong regulatory role on NK cell's function.

Conclusion

Ascorbic acid could promote the proliferation of the CAD patients' NK cells; LDH serum level may function as an indicator for NK cell proliferation capability and an immune-regulatory factor.

Cancer associated fibroblasts and metabolic reprogramming: unraveling the intricate crosstalk in tumor evolution

Metabolic reprogramming provides tumors with an energy source and biofuel to support their survival in the malignant microenvironment. Extensive research into the intrinsic oncogenic mechanisms of the tumor microenvironment (TME) has established that cancer-associated fibroblast (CAFs) and metabolic reprogramming regulates tumor progression through numerous biological activities, including tumor immunosuppression, chronic inflammation, and ecological niche remodeling. Specifically, immunosuppressive TME formation is promoted and mediators released via CAFs and multiple immune cells that collectively support chronic inflammation, thereby inducing pre-metastatic ecological niche formation, and ultimately driving a vicious cycle of tumor proliferation and metastasis. This review comprehensively explores the process of CAFs and metabolic regulation of the dynamic evolution of tumor-adapted TME, with particular focus on the mechanisms by which CAFs promote the formation of an immunosuppressive microenvironment and support metastasis. Existing findings confirm that multiple components of the TME act cooperatively to accelerate the progression of tumor events. The potential applications and challenges of targeted therapies based on CAFs in the clinical setting are further discussed in the context of advancing research related to CAFs.

Cancer-associated fibroblasts promote proliferation, angiogenesis, metastasis and immunosuppression in gastric cancer

Despite advances in surgery, radiotherapy and immunotherapy, the mortality rate for gastric cancer remains one of the highest in the world. A large body of evidence has demonstrated that cancer-associated fibroblasts (CAFs), as core members of the stroma, can secrete cytokines, proteins and exosomes to create a tumour microenvironment that is conducive to cancer cell survival. CAFs can also interact with cancer cells to form a complex signalling network, enabling cancer cells to more easily metastasise to other organs and tissues in the body and develop metastatic foci. In this review, we provide an overview of the CAFs concept and activators. We focus on elucidating their effects on immune cells, intratumoural vasculature, extracellular matrix, as well as cancer cell activity, metastatic power and metabolism, and on enhancing the metastatic ability of cancer cells through activation of JAK/STAT, NF/κB and CXCL12/CXCR4. Various therapeutic agents targeting CAFs are also under development and are expected to improve the prognosis of gastric cancer in combination with existing treatment options.

Regulation of gut microbiota on immune cell ferroptosis: A novel insight for immunotherapy against tumor

Gut microbiota contributes to the homeostasis of immune system and is related to various diseases such as tumorigenesis. Ferroptosis, a new type of cell death, is also involved in the disease pathogenesis. Recent studies have found the correlations of gut microbiota mediated ferroptosis and immune cell death. Gut microbiota derived immunosuppressive metabolites, which can promote differentiation and function of immune cells, tend to inhibit ferroptosis through their receptors, whereas inflammatory metabolites from gut microbiota also affect the differentiation and function of immune cells and their ferroptosis. Thus, it is possible for gut microbiota to regulate immune cell ferroptosis. Indeed, gut microbiota metabolite receptor aryl hydrocarbon receptor (AhR) can affect ferroptosis of intestinal intraepithelial lymphocytes, leading to disease pathogenesis. Since immune cell ferroptosis in tumor microenvironment (TME) affects the occurrence and development of tumor, the modulation of gut microbiota in these cell ferroptosis might influence on the tumorigenesis, and also immunotherapy against tumors. Here we will summarize the recent advance of ferroptosis mediated by gut microbiota metabolites, which potentially acts as regulator(s) on immune cells in TME for therapy against tumor.

Integrating single-cell transcriptomics to reveal the ferroptosis regulators in the tumor microenvironment that contribute to bladder urothelial carcinoma progression and immunotherapy

Background

Ferroptosis, as a novel form of programmed cell death, plays a crucial role in the occurrence and development of bladder cancer (BCa). However, the regulatory mechanisms of ferroptosis in the tumor microenvironment (TME) of BCa remain to be elucidated.

Methods

Based on single-cell RNA (scRNA) transcriptomic data of BCa, we employed non-negative matrix factorization (NMF) dimensionality reduction clustering to identify novel ferroptosis-related cell subtypes within the BCa TME, aiming to explore the biological characteristics of these TME cell subtypes. Subsequently, we conducted survival analysis and univariate Cox regression analysis to explore the prognostic significance of these cell subtypes. We investigated the relationship between specific subtypes and immune infiltration, as well as their implications for immunotherapy. Finally, we discovered a valuable and novel biomarker for BCa, supported by a series of in vitro experiments.

Results

We subdivided cancer-associated fibroblasts (CAFs), macrophages, and T cells into 3-5 small subpopulations through NMF and further explored the biological features. We found that ferroptosis played an important role in the BCa TME. Through bulk RNA-seq analysis, we further verified that ferroptosis affected the progression, prognosis, and immunotherapy response of BCa by regulating the TME. Especially ACSL4+CAFs, we found that high-level infiltration of this CAF subtype predicted worse prognosis, more complex immune infiltration, and less response for immunotherapy. Additionally, we found that this type of CAF was associated with cancer cells through the PTN-SDC1 axis, suggesting that SDC1 may be crucial in regulating CAFs in cancer cells. A series of in vitro experiments confirmed these inferences: SDC1 promoted the progression of BCa. Interestingly, we also discovered FTH1+ macrophages, which were closely related to SPP1+ macrophages and may also be involved in the regulation of BCa TME.

Conclusion

This study revealed the significant impact of ferroptosis on bladder cancer TME and identified novel ferroptosis-related TME cell subpopulations, ACSL4+CAFs, and important BCa biomarker SDC1.

Immunometabolism of ferroptosis in the tumor microenvironment

Ferroptosis is an iron-dependent form of cell death that results from excess lipid peroxidation in cellular membranes. Within the last decade, physiological and pathological roles for ferroptosis have been uncovered in autoimmune diseases, inflammatory conditions, infection, and cancer biology. Excitingly, cancer cell metabolism may be targeted to induce death by ferroptosis in cancers that are resistant to other forms of cell death. Ferroptosis sensitivity is regulated by oxidative stress, lipid metabolism, and iron metabolism, which are all influenced by the tumor microenvironment (TME). Whereas some cancer cell types have been shown to adapt to these stressors, it is not clear how immune cells regulate their sensitivities to ferroptosis. In this review, we discuss the mechanisms of ferroptosis sensitivity in different immune cell subsets, how ferroptosis influences which immune cells infiltrate the TME, and how these interactions can determine epithelial-to-mesenchymal transition (EMT) and metastasis. While much focus has been placed on inducing ferroptosis in cancer cells, these are important considerations for how ferroptosis-modulating strategies impact anti-tumor immunity. From this perspective, we also discuss some promising immunotherapies in the field of ferroptosis and the challenges associated with targeting ferroptosis in specific immune cell populations.

The evolving process of ferroptosis in thyroid cancer: Novel mechanisms and opportunities

Thyroid cancer (TC) is a prevalent endocrine malignancy, with a significant increase in incidence worldwide. Ferroptosis is a novel form of programmed cell death, primarily caused by iron overload and reactive oxygen species (ROS)-dependent accumulation of lipid peroxides. The main manifestations of cellular ferroptosis are rupture of the outer membrane, crumpling of the mitochondria and shrinkage or disappearance of the mitochondrial cristae, thus leading to cell death. Ferroptosis is an important phenomenon in tumour progression, with crosstalk with tumour-associated signalling pathways profoundly affecting tumour progression, immune effects and treatment outcomes. The functions and mechanisms of ferroptosis in TC have also attracted increasing attention, mainly in terms of influencing tumour proliferation, invasion, migration, immune response, therapeutic susceptibility and genetic susceptibility. However, at present, the tumour biology of the morphological, biological and mechanism pathways of ferroptosis is much less deep in TC than in other malignancies. Hence, in this review, we highlighted the emerging role of ferroptosis in TC progression, including the novel mechanisms and potential opportunities for diagnosis and treatment, as well as discussed the limitations and prospects. Ferroptosis-based diagnostic and therapeutic strategies can potentially provide complementary management of TCs.

Cancer Cell Secreted Legumain Promotes Gastric Cancer Resistance to Anti-PD-1 Immunotherapy by Enhancing Macrophage M2 Polarization

The interaction between cancer cells and immune cells plays critical roles in gastric cancer (GC) progression and immune evasion. Forced legumain (LGMN) is one of the characteristics correlated with poor prognosis in gastric cancer patients. However, the role of gastric-cancer-secreted LGMN (sLGMN) in modulating the tumor immune microenvironment and the biological effect on the immune evasion of gastric cancer remains unclear. In this study, we found that forced expression of sLGMN in gastric cancer serum correlates with increased M2 macrophage infiltration in GC tissues and predicted resistance to anti-PD-1 immunotherapy. Mechanistically, gastric cancer cells secrete LGMN via binding to cell surface Integrin αvβ3, then activate Integrin αvβ3/PI3K (Phosphatidylinositol-4,5-bisphosphate3-kinase)/AKT (serine/threonine kinase)/mTORC2 (mammalian target of rapamycin complex 2) signaling, promote metabolic reprogramming, and polarize macrophages from the M1 to the M2 phenotype. Either blocking LGMN, Integrin αv, or knocking out Integrin αv expression and abolishing the LGMN/Integrin αvβ3 interaction significantly inhibits metabolic reprogramming and polarizes macrophages from the M1 to the M2 phenotype. This study reveals a critical molecular crosstalk between gastric cancer cells and macrophages through the sLGMN/Integrinαvβ3/PI3K/AKT/mTORC2 axis in promoting gastric cancer immune evasion and resistance to anti-PD-1 immunotherapy, indicating that the sLGMN/Integrinαvβ3/PI3K/AKT/mTORC2 axis may act as a promising therapeutic target.

The emerging role of nuclear receptor coactivator 4 in health and disease: a novel bridge between iron metabolism and immunity

Nuclear receptor coactivator 4 (NCOA4) has recently been recognized as a selective cargo receptor of ferritinophagy participating in ferroptosis. However, NCOA4 is also a coactivator that modulates the transcriptional activity of many vital nuclear receptors. Recent novel studies have documented the role of NCOA4 in healthy and pathogenic conditions via its modulation of iron- and non-iron-dependent metabolic pathways. NCOA4 exhibits non-ferritinophagic and iron-independent features such as promoting tumorigenesis and erythropoiesis, immunomodulation, regulating autophagy, and participating in DNA replication and mitosis. Full-length human-NCOA4 is composed of 614 amino acids, of which the N-terminal (1-237) contains nuclear-receptor-binding domains, while the C-terminal (238-614) principally contains a ferritin-binding domain. The exploration of the protein structure of NCOA4 suggests that NCOA4 possesses additional significant and complex functions based on its structural domains. Intriguingly, another three isoforms of NCOA4 that are produced by alternative splicing have been identified, which may also display disparate activities in physiological and pathological processes. Thus, NCOA4 has become an important bridge that encompasses interactions between immunity and metabolism. In this review, we outline the latest advances in the important regulating mechanisms underlying NCOA4 actions in health and disease conditions, providing insights into potential therapeutic interventions.

Organoids in gastrointestinal diseases: from bench to clinic

The etiology of gastrointestinal (GI) diseases is intricate and multifactorial, encompassing complex interactions between genetic predisposition and gut microbiota. The cell fate change, immune function regulation, and microenvironment composition in diseased tissues are governed by microorganisms and mutated genes either independently or through synergistic interactions. A comprehensive understanding of GI disease etiology is imperative for developing precise prevention and treatment strategies. However, the existing models used for studying the microenvironment in GI diseases-whether cancer cell lines or mouse models-exhibit significant limitations, which leads to the prosperity of organoids models. This review first describes the development history of organoids models, followed by a detailed demonstration of organoids application from bench to clinic. As for bench utilization, we present a layer-by-layer elucidation of organoid simulation on host-microbial interactions, as well as the application in molecular mechanism analysis. As for clinical adhibition, we provide a generalized interpretation of organoid application in GI disease simulation from inflammatory disorders to malignancy diseases, as well as in GI disease treatment including drug screening, immunotherapy, and microbial-targeting and screening treatment. This review draws a comprehensive and systematical depiction of organoids models, providing a novel insight into the utilization of organoids models from bench to clinic.

Organoid models: the future companions of personalized drug development

High failure rates of the current drug development process are driving exemplary changes toward methodologies centered on human diseasein-vitromodeling. Organoids are self-organized tissue sub-units resembling their organ of origin and are widely acknowledged for their unique potential in recapitulating human physio-pathological mechanisms. They are transformative for human health by becoming the platform of choice to probe disease mechanisms and advance new therapies. Furthermore, the compounds' validation as therapeutics represents another point of the drug development pipeline where organoids may provide key understandings and help pharma organizations replace or reduce animal research. In this review, we focus on gastrointestinal organoid models, which are currently the most advanced organoid models in drug development. We focus on experimental validations of their value, and we propose avenues to enhance their use in drug discovery and development, as well as precision medicine and diagnostics.

Cancer-associated fibroblasts: heterogeneity and their role in the tumor immune response

In recent decades, many reports have been published on the composition and function of the tumor microenvironment (TME), among which cancer-associated fibroblasts (CAFs) have received much attention. CAFs have different degrees of heterogeneity in terms of their origin, phenotype, and function and can be divided into different subpopulations. These subgroups may play different roles in the occurrence and development of tumors. In addition, CAFs are closely associated with tumor immunity and have been found to regulate immune cell activity and to suppress the tumor immune response. In this review, we systematize the heterogeneity and characteristics of CAFs, discuss how specific CAF subgroups contribute to cancer progression by inducing an immunosuppressive microenvironment, and finally, we examine the future clinical applications of CAF subgroups.

Regulation of anti-tumor immunity by metal ion in the tumor microenvironment

Metal ions play an essential role in regulating the functions of immune cells by transmitting intracellular and extracellular signals in tumor microenvironment (TME). Among these immune cells, we focused on the impact of metal ions on T cells because they can recognize and kill cancer cells and play an important role in immune-based cancer treatment. Metal ions are often used in nanomedicines for tumor immunotherapy. In this review, we discuss seven metal ions related to anti-tumor immunity, elucidate their roles in immunotherapy, and provide novel insights into tumor immunotherapy and clinical applications.

Long-term 4-nonylphenol exposure drives cervical cell malignancy through MAPK-mediated ferroptosis inhibition

4-NP (4-nonylphenol), a prevalent environmental endocrine disruptor with estrogenic properties, is commonly detected in drinking water and food sources. It poses a significant risk of endocrine disruption, thereby influencing the onset and progression of diverse diseases, including tumorigenesis. However, its specific impact on cervical cancer remains to be fully elucidated. Our study focused on the biological effects of sustained exposure to low-dose 4-NP on human normal cervical epithelial cells (HcerEpic). After a continuous 30-week exposure to 4-NP, the treated cells exhibited a significant malignant transformation, whereas the solvent control group showed limited malignant phenotypes. Subsequent analyses of the metabolomic profiles of the transformed cells unveiled marked irregularities in glutathione metabolism and unsaturated fatty acid metabolism. Analyses of transcriptomic profiles revealed significant activation of the MAPK signaling pathway and suppression of ferroptosis processes in these cells. Furthermore, the expression of MT2A was significantly upregulated following 4-NP exposure. Knockdown of MT2A restored the aberrant activation of the MAPK signaling pathway, elevated antioxidant capacity, ferroptosis inhibition, and ultimately the development of malignant phenotypes that induced by 4-NP in the transformed cells. Mechanistically, MT2A increased cellular antioxidant capabilities and facilitated the removal of toxic iron ions by enhancing the phosphorylation of ERK1/2 and JNK MAPK pathways. The administration of activators and inhibitors of the MAPK pathway confirmed that the MAPK pathway mediated the 4-NP-induced suppression of ferroptosis and, ultimately, the malignant transformation of cervical epithelial cells. Overall, our findings elucidated a dynamic molecular transformation induced by prolonged exposure to 4-NP, and delineated comprehensive biological perspectives underlying 4-NP-induced cervical carcinogenesis. This offers novel theoretical underpinnings for the assessment of the carcinogenic risks associated with 4-NP.

Metabolic adaptations determine whether natural killer cells fail or thrive within the tumor microenvironment

Natural Killer (NK) cells are a top contender in the development of adoptive cell therapies for cancer due to their diverse antitumor functions and ability to restrict their activation against nonmalignant cells. Despite their success in hematologic malignancies, NK cell-based therapies have been limited in the context of solid tumors. Tumor cells undergo various metabolic adaptations to sustain the immense energy demands that are needed to support their rapid and uncontrolled proliferation. As a result, the tumor microenvironment (TME) is depleted of nutrients needed to fuel immune cell activity and contains several immunosuppressive metabolites that hinder NK cell antitumor functions. Further, we now know that NK cell metabolic status is a main determining factor of their effector functions. Hence, the ability of NK cells to withstand and adapt to these metabolically hostile conditions is imperative for effective and sustained antitumor activity in the TME. With this in mind, we review the consequences of metabolic hostility in the TME on NK cell metabolism and function. We also discuss tumor-like metabolic programs in NK cell induced by STAT3-mediated expansion that adapt NK cells to thrive in the TME. Finally, we examine how other approaches can be applied to enhance NK cell metabolism in tumors.

Effects of Splenectomy on Natural Killer Cell Levels in β-Thalassemia Major Patients

AIM

In this study, we investigated how splenectomy affects natural killer (NK) cell levels in patients with β-thalassemia major (β-TM).

MATERIALS AND METHODS

Seventy patients with β-TM (38 splenectomized and 32 nonsplenectomized) and 25 healthy controls were included in this study. The hemogram parameters, ferritin, T lymphocyte, T-helper cell, T-suppressor cell, and NK cell numbers, were measured.

RESULTS

The T lymphocyte (CD3+) level was found to be significantly higher in the patient group (p < 0.05). CD3+/CD4+ T lymphocytes were detected to be significantly higher in the patient group (p < 0.05). Although the CD3+/CD4+ T lymphocyte level was significantly higher in the nonsplenectomy group (p < 0.05), this was not the case in the splenectomy group. When the patient and control groups were compared, no significant difference was detected regarding CD3+/CD8+ T lymphocyte levels. CD3-/CD16+CD56+ NK cell level was found to be significantly lower only in the splenectomy group than in the control group (p < 0.05). We found that there was a significant negative correlation between serum ferritin levels and both total lymphocyte (r = -0.617) and CD3+ lymphocyte (r = -0.718) levels in the control group (p < 0.05). A significant negative correlation was detected between serum ferritin levels and CD3-/CD16+CD56+ NK cell levels in the patient group (r = -0.410) (p < 0.05).

CONCLUSION

Splenectomy reduces NK cell levels in patients with β-TM. The negative relationship between ferritin levels and NK cells indicates that ferritin levels should be kept under control in patients with β-TM.

Ferroptosis in cancer: From molecular mechanisms to therapeutic strategies

Ferroptosis is a non-apoptotic form of regulated cell death characterized by the lethal accumulation of iron-dependent membrane-localized lipid peroxides. It acts as an innate tumor suppressor mechanism and participates in the biological processes of tumors. Intriguingly, mesenchymal and dedifferentiated cancer cells, which are usually resistant to apoptosis and traditional therapies, are exquisitely vulnerable to ferroptosis, further underscoring its potential as a treatment approach for cancers, especially for refractory cancers. However, the impact of ferroptosis on cancer extends beyond its direct cytotoxic effect on tumor cells. Ferroptosis induction not only inhibits cancer but also promotes cancer development due to its potential negative impact on anticancer immunity. Thus, a comprehensive understanding of the role of ferroptosis in cancer is crucial for the successful translation of ferroptosis therapy from the laboratory to clinical applications. In this review, we provide an overview of the recent advancements in understanding ferroptosis in cancer, covering molecular mechanisms, biological functions, regulatory pathways, and interactions with the tumor microenvironment. We also summarize the potential applications of ferroptosis induction in immunotherapy, radiotherapy, and systemic therapy, as well as ferroptosis inhibition for cancer treatment in various conditions. We finally discuss ferroptosis markers, the current challenges and future directions of ferroptosis in the treatment of cancer.