Nonferrous Ferroptosis Inducer Manganese Molybdate Nanoparticles to Enhance Tumor Immunotherapy

Tumor microenvironment modulation innovates combinative cancer therapy via a versatile graphene oxide nanosystem

The tumor microenvironment (TME) emerges as a unique challenge to oncotherapy due to its intricate ecosystem containing diverse cell types, extracellular matrix, secreted factors, and neovascularization, which furnish tumor growth, progression, invasion, and metastasis. Graphene oxide (GO)-based materials have garnered increasing attention in cancer therapy owing to their vast specific surface area, flexible lamellar structure, and electronic-photonic properties. Recently, interactions of GO with the TME have been broadly investigated, including trapping biomolecules, catalysis, cancer stem cell targeting, immunoreactions, etc., which inspires combinative therapeutic strategies to overcome TME obstacles. Herein, we summarize TME features, GO modulating various dimensions of the TME, and a TME-triggerable drug delivery system and highlight innovation and merits in combinative cancer therapy based on TME modulation. This review aims to offer researchers deeper insights into the interactions between versatile GO nanomaterials and the TME, facilitating the development of rational and reliable GO-based nanomedicines for advanced oncotherapy.

The Regulation of Trace Metal Elements in Cancer Ferroptosis

Ferroptosis, as novel type of regulated cell death that has garnered widespread attention over the past decade, has witnessed the continuous discovery of an increasing number of regulatory mechanisms. Trace metal elements play a multifaceted and crucial role in oncology. Interestingly, it has been increasingly evident that these elements, such as copper, are involved in the regulation of iron accumulation, lipid peroxidation and antiferroptotic systems, suggesting the existence of "nonferrous" mechanisms in ferroptosis. In this review, a comprehensive overview of the composition and mechanism of ferroptosis is provided. The interaction between copper metabolism (including cuproptosis) and ferroptosis in cancer, as well as the roles of other trace metal elements (such as zinc, manganese, cobalt, and molybdenum) in ferroptosis are specifically focused. Furthermore, the applications of nanomaterials based on these metals in cancer therapy are also reviewed and potential strategies for co-targeting ferroptosis and cuproptosis are explored. Nevertheless, in light of the intricate and ambiguous nature of these interactions, ongoing research is essential to further elucidate the "nonferrous" mechanisms of ferroptosis, thereby facilitating the development of novel therapeutic targets and approaches for cancer treatment.

Fe/Mo-Based Lipid Peroxidation Nanoamplifier Combined with Adenosine Immunometabolism Regulation to Augment Anti-Breast Cancer Immunity

Immunogenic cell death (ICD)-mediated immunization strategies have great potential against breast cancer. However, traditional strategies neglect the increase in the immunosuppressive metabolite, adenosine (ADO), during ICD, leading to insufficient therapeutic outcomes. In this study, it is found that the adenosine A2A receptor (A2AR) is significantly expressed in breast cancer and positively associated with regulatory T (Treg) cells. Herein, a strategy combining Fe/Mo-based lipid peroxidation (LPO) nanoamplifiers and A2AR blockade is reported to maximize ICD-mediated anti-tumor immunity. This LPO nanoamplifier causes LPO explosion by the Fe (II)-mediated Fenton reaction and Mo(V)-mediated Russell mechanism. Subsequently, it elicits the ICD magnification of tumor cells by inducing multiple regulated cell death patterns of ferroptosis, apoptosis, and necroptosis. Additionally, the A2AR antagonist (SCH58261), an immunometabolic checkpoint blocker, is found to relieve ADO-related immunosuppression, amplify anti-tumor immunological effects, and elicit immune memory responses. This robust anti-tumor immunity is observed in primary, distant, pulmonary metastatic, and recurrent tumors. This study provides a novel strategy for optimizing ICD-mediated immunotherapy and highlights the benefits of combining LPO explosion with A2AR blockade to enhance breast cancer immunotherapy.

Advances in Manganese-based nanomaterials for cancer therapy via regulating Non-Ferrous ferroptosis

Ferroptosis, a regulated form of cell death distinct from apoptosis, was first identified in 2012 and is characterized by iron-dependent lipid peroxidation driven by reactive oxygen species (ROS). Since its discovery, ferroptosis has been linked to various diseases, with recent studies highlighting its potential in cancer therapy, particularly for targeting cancer cells that are resistant to traditional treatments like chemotherapy and radiotherapy. While iron has historically been central to ferroptosis, emerging evidence indicates that non-ferrous ions, especially manganese (Mn), also play a crucial role in modulating this process. Mn-based nanomaterials have shown significant promise in cancer treatment by enhancing ROS production, depleting antioxidant defenses, and inducing ferroptosis. Additionally, these materials offer advantages in tumor imaging, immunotherapy, and catalyzing the Fenton-like reactions essential for ferroptosis. This review delves into the mechanisms of Mn-induced ferroptosis, focusing on recent advancements in Mn-based nanomaterials and their applications in chemodynamic therapy and immunotherapy. By leveraging non-ferrous ion-mediated ferroptosis, these approaches provide a novel avenue for cancer treatment. Furthermore, this review explores the potential role of Mn-based nanomaterials in the lipid metabolism pathways involved in ferroptosis and highlights the advantages of Mn ions over other metals in promoting ferroptosis. These insights offer new perspectives for the development of tumor therapies centered on Mn-based nanomaterials.

Oxymatrine Inhibits PD-L1 by Downregulating IFN-γ to Promote Ferroptosis and Enhance Anti-PD-L1 Efficacy in Liver Cancer

Purpose

Oxymatrine has potent anti-cancer activity, but its exact mechanism in liver cancer remains elusive. The present study was designated to explore oxymatrine's effect and the potential mechanism on Programmed cell death-ligand 1 (PD-L1) expression and ferroptosis in liver cancer.

Methods

Oxymatrine's influence on PD-L1 expression and ferroptosis-related proteins in liver cancer cells was explored in vitro and in vivo utilizing Western blotting, qRT-PCR, immunofluorescence, ELISA, H&E staining, immunohistochemistry, as well as detection of Fe2+, ROS, and MDA.

Results

The in-vivo results showed that xenotransplanted tumor mice with drug interventions (oxymatrine, anti-PD-L1, and combination groups) exhibited inhibited tumor growth compared to control mice. Relative to anti-PD-L1 administration alone, the combined treatment inhibited tumor growth more significantly, along with reduced interferon-γ (IFN-γ) expression in peripheral blood and remarkably increased tumor immune lymphocyte (CD4+ T and CD8+ T) infiltration in cancer tissues. Meanwhile, PD-L1, xCT, and GPX4 protein levels in the combination group were significantly downregulated. According to the in vitro results, IFN-γ promoted PD-L1, xCT, and GPX4 protein levels in liver cancer cell lines. Oxymatrine reversed IFN-γ-induced upregulation of PD-L1 expression; moreover, it downregulated xCT and GPX4 protein levels in liver cancer cells and promoted intracellular Fe2+, ROS, and MDA levels.

Conclusion

Oxymatrine promotes tumor immune response and ferroptosis in liver cancer by downregulating IFN-γ and synergistically enhances the inhibitory effect of anti-PD-L1 on liver cancer.

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.

Ferroptosis Inducing Co(III) Polypyridine Sulfasalazine Complex for Therapeutically Enhanced Anticancer Therapy

Despite significant improvements in the treatment of cancerous tumors in the last decades, cancer remains one of the deadliest diseases worldwide. To overcome the shortcomings of currently applied chemotherapeutic treatments, much research efforts have been devoted towards the development of ferroptosis inducing anticancer agents. Ferroptosis is a newly described form of regulated, non-apoptotic cell death that is associated with high potential inside the clinics. Herein, the chemical synthesis and biological evaluation of a Co(III) polypyridine sulfasalazine complex as a ferroptosis inducer is reported. Upon entering the cancerous cells, the metal complex primarily accumulated in the mitochondria, triggering the production of hydroxy radicals and lipid peroxides, ultimately causing cell death by ferroptosis. The compound demonstrated to eradicate various monolayer cancer cells as well as colon carcinoma multicellular tumor spheroids. To the best of our knowledge this study reports on the first example of a Co(III) complex that is capable of inducing ferroptosis.

The Mutual Regulatory Role of Ferroptosis and Immunotherapy in Anti-tumor Therapy

Ferroptosis is a form of cell death that is triggered by the presence of ferrous ions and is characterized by lipid peroxidation induced by these ions. The mechanism exhibits distinct morphological characteristics compared to apoptosis, autophagy, and necrosis. A notable aspect of ferroptosis is its ability to inhibit uncontrolled tumor replication and immortalization, especially in malignant, drug-resistant, and metastatic tumors. Additionally, immunotherapy, a novel therapeutic approach for tumors, has been found to have a reciprocal regulatory relationship with ferroptosis in the context of anti-tumor therapy. A comprehensive analysis of ferroptosis and immunotherapy in tumor therapy is presented in this paper, highlighting the potential for mutual adjuvant effects. Specifically, we discuss the mechanisms underlying ferroptosis and immunotherapy, emphasizing their ability to improve the tumor immune microenvironment and enhance immunotherapeutic effects. Furthermore, we investigate how immunotherapeutic factors may increase the sensitivity of tumor cells to ferroptosis. We aim to provide a prospective view of the promising value of combined ferroptosis and immunotherapy in anticancer therapy by elucidating the mutual regulatory network between each.

Inorganic Nanomedicine-Mediated Ferroptosis: A Synergistic Approach to Combined Cancer Therapies and Immunotherapy

Ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation, has generated substantial interest in cancer therapy. Various methods have been developed to induce ferroptosis in tumor cells, including approved drugs, experimental compounds, and nanomedicine formulations. Unlike apoptosis, ferroptosis presents unique molecular and cellular features, representing a promising approach for cancers resistant to conventional treatments. Recent research indicates a strong link between ferroptosis and the tumor immune microenvironment, suggesting the potential of ferroptosis to trigger robust antitumor immune responses. Multiple cellular metabolic pathways control ferroptosis, including iron, lipid, and redox metabolism. Thus, understanding the interaction between tumor metabolism and ferroptosis is crucial for developing effective anticancer therapies. This review provides an in-depth discussion on combining inorganic nanoparticles with cancer therapies such as phototherapy, chemotherapy, radiotherapy, and immunotherapy, and the role of ferroptosis in these combination treatments. Furthermore, this paper explores the future of tumor treatment using nanomedicine, focusing on how inorganic nanoparticles can enhance ferroptosis in tumor cells and boost antitumor immunity. The goal is to advance ferroptosis-based nanomedicine from the laboratory to clinical applications.

Enhancing Colorectal Cancer Immunotherapy: The Pivotal Role of Ferroptosis in Modulating the Tumor Microenvironment

Colorectal cancer (CRC) represents a significant challenge in oncology, with increasing incidence and mortality rates worldwide, particularly among younger adults. Despite advancements in treatment modalities, the urgent need for more effective therapies persists. Immunotherapy has emerged as a beacon of hope, offering the potential for improved outcomes and quality of life. This review delves into the critical interplay between ferroptosis, an iron-dependent form of regulated cell death, and immunotherapy within the CRC context. Ferroptosis's influence extends beyond tumor cell fate, reshaping the tumor microenvironment (TME) to enhance immunotherapy's efficacy. Investigations into Ferroptosis-related Genes (OFRGs) reveal their pivotal role in modulating immune cell infiltration and TME composition, closely correlating with tumor responsiveness to immunotherapy. The integration of ferroptosis inducers with immunotherapeutic strategies, particularly through novel approaches like ferrotherapy and targeted co-delivery systems, showcases promising avenues for augmenting treatment efficacy. Furthermore, the expression patterns of OFRGs offer novel prognostic tools, potentially guiding personalized and precision therapy in CRC. This review underscores the emerging paradigm of leveraging ferroptosis to bolster immunotherapy's impact, highlighting the need for further research to translate these insights into clinical advancements. Through a deeper understanding of the ferroptosis-immunotherapy nexus, new therapeutic strategies can be developed, promising enhanced efficacy and broader applicability in CRC treatment, ultimately improving patient outcomes and quality of life in the face of this formidable disease.

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.

Hypoxia-Specific Metal-Organic Frameworks Augment Cancer Immunotherapy of High-Intensity Focused Ultrasound

As a noninvasive treatment modality, high-intensity focused ultrasound (HIFU)-induced antitumor immune responses play a vital role in surgery prognosis. However, limited response intensity largely hinders postoperative immunotherapy. Herein, a hypoxia-specific metal-organic framework (MOF) nanosystem, coordinated by Fe3+, hypoxic-activated prodrug AQ4N, and IDO-1 signaling pathway inhibitor NLG919, is developed for the potentiating immunotherapy of HIFU surgery. The loaded AQ4N enhances the photoacoustic imaging effects to achieve accurate intraoperative navigation. Within the HIFU-established severe hypoxic environment, AQ4N is activated sequentially, following which it cooperates with Fe3+ to effectively provoke immunogenic cell death. In addition, potent NLG919 suppresses IDO-1 activity and degrades the immunosuppressive tumor microenvironment aggravated by postoperative hypoxia. In vivo studies demonstrate that the MOF-mediated immunotherapy greatly inhibits the growth of primary/distant tumors and eliminates lung metastasis. This work establishes a robust delivery platform to improve immunotherapy and the overall prognosis of HIFU surgery with high specificity and potency.

Trace elements in pancreatic cancer

BACKGROUND

Pancreatic cancer (PCA) is an extremely aggressive malignant cancer with an increasing incidence and a low five-year survival rate. The main reason for this high mortality is that most patients are diagnosed with PCA at an advanced stage, missing early treatment options and opportunities. As important nutrients of the human body, trace elements play an important role in maintaining normal physiological functions. Moreover, trace elements are closely related to many diseases, including PCA.

REVIEW

This review systematically summarizes the latest research progress on selenium, copper, arsenic, and manganese in PCA, elucidates their application in PCA, and provides a new reference for the prevention, diagnosis and treatment of PCA.

CONCLUSION

Trace elements such as selenium, copper, arsenic and manganese are playing an important role in the risk, pathogenesis, diagnosis and treatment of PCA. Meanwhile, they have a certain inhibitory effect on PCA, the mechanism mainly includes: promoting ferroptosis, inducing apoptosis, inhibiting metastasis, and inhibiting excessive proliferation.

Engineering Nanozymes for Tumor Therapy via Ferroptosis Self-Amplification

Ferroptosis induction is an emerging strategy for tumor therapy. Reactive oxygen species (ROS) can induce ferroptosis but are easily consumed by overexpressed glutathione (GSH) in tumor cells. Therefore, achieving a large amount of ROS production in tumor cells without being consumed is key to efficiently inducing ferroptosis. In this study, a self-amplifying ferroptosis-inducing therapeutic agent, Pd@CeO2-Fe-Co-WZB117-DSPE-PEG-FA (PCDWD), is designed for tumor therapy. PCDWD exhibits excellent multi-enzyme activities due to the loading of Fe-Co dual atoms with abundant active sites, including peroxidase-like enzymes, catalase-like enzymes, and glutathione oxidases (GSHOx), which undergo catalytic reactions in the tumor microenvironment to produce ROS, thereby inducing ferroptosis. Furthermore, PCDWD can also deplete GSH in tumor cells, thus reducing the consumption of ROS by GSH and inhibiting the expression of GSH peroxidase 4. Moreover, the photothermal effect of PCDWD can not only directly kill tumor cells but also further enhance its own enzyme activities, consequently promoting ferroptosis in tumor cells. In addition, WZB117 can reduce the expression of heat shock protein 90 by inhibiting glucose transport, thereby reducing the thermal resistance of tumor cells and further improving the therapeutic effect. Finally, X-ray computed tomography imaging of PCDWD guides it to achieve efficient tumor therapy.

Ferroptosis resistance in cancer cells: nanoparticles for combination therapy as a solution

Ferroptosis is a form of regulated cell death (RCD) characterized by iron-dependent lipid peroxidation. Ferroptosis is currently proposed as one of the most promising means of combating tumor resistance. Nevertheless, the problem of ferroptosis resistance in certain cancer cells has been identified. This review first, investigates the mechanisms of ferroptosis induction in cancer cells. Next, the problem of cancer cell resistance to ferroptosis, as well as the underlying mechanisms is discussed. Recently discovered ferroptosis-suppressing biomarkers have been described. The various types of nanoparticles that can induce ferroptosis are also discussed. Given the ability of nanoparticles to combine multiple agents, this review proposes nanoparticle-based ferroptosis cell death as a viable method of circumventing this resistance. This review suggests combining ferroptosis with other forms of cell death, such as apoptosis, cuproptosis and autophagy. It also suggests combining ferroptosis with immunotherapy.

Progress and Challenges in Tumor Ferroptosis Treatment Strategies: A Comprehensive Review of Metal Complexes and Nanomedicine

Ferroptosis is a new form of regulated cell death featuring iron-dependent lipid peroxides accumulation to kill tumor cells. A growing body of evidence has shown the potential of ferroptosis-based cancer therapy in eradicating refractory malignancies that are resistant to apoptosis-based conventional therapies. In recent years, studies have reported a number of ferroptosis inducers that can increase the vulnerability of tumor cells to ferroptosis by regulating ferroptosis-related signaling pathways. Encouraged by the rapid development of ferroptosis-driven cancer therapies, interdisciplinary fields that combine ferroptosis, pharmaceutical chemistry, and nanotechnology are focused. First, the prerequisites and metabolic pathways for ferroptosis are briefly introduced. Then, in detail emerging ferroptosis inducers designed to boost ferroptosis-induced tumor therapy, including metal complexes, metal-based nanoparticles, and metal-free nanoparticles are summarized. Subsequently, the application of synergistic strategies that combine ferroptosis with apoptosis and other regulated cell death for cancer therapy, with emphasis on the use of both cuproptosis and ferroptosis to induce redox dysregulation in tumor and intracellular bimetallic copper/iron metabolism disorders during tumor treatment is discussed. Finally, challenges associated with clinical translation and potential future directions for potentiating cancer ferroptosis therapies are highlighted.

Ferroptosis: emerging roles in lung cancer and potential implications in biological compounds

Lung cancer has high metastasis and drug resistance. The prognosis of lung cancer patients is poor and the patients' survival chances are easily neglected. Ferroptosis is a programmed cell death proposed in 2012, which differs from apoptosis, necrosis and autophagy. Ferroptosis is a novel type of regulated cell death which is driven by iron-dependent lipid peroxidation and subsequent plasma membrane ruptures. It has broad prospects in the field of tumor disease treatment. At present, multiple studies have shown that biological compounds can induce ferroptosis in lung cancer cells, which exhibits significant anti-cancer effects, and they have the advantages in high safety, minimal side effects, and less possibility to drug resistance. In this review, we summarize the biological compounds used for the treatment of lung cancer by focusing on ferroptosis and its mechanism. In addition, we systematically review the current research status of combining nanotechnology with biological compounds for tumor treatment, shed new light for targeting ferroptosis pathways and applying biological compounds-based therapies.

Chemo-photothermal nanoplatform with diselenide as the key for ferroptosis in colorectal cancer

Colorectal cancer (CRC) is a prevalent clinical malignancy of the gastrointestinal system, and its clinical drug resistance is the leading cause of poor prognosis. Mechanistically, CRC cells possess a specific oxidative stress defense mechanism composed of a significant number of endogenous antioxidants, such as glutathione, to combat the damage produced by drug-induced excessive reactive oxygen species (ROS). We report on a new anti-CRC nanoplatform, a multifunctional chemo-photothermal nanoplatform based on Camptothecin (CPT) and IR820, an indocyanine dye. The implementation of a GSH-triggered ferroptosis-integrated tumor chemo-photothermal nanoplatform successfully addressed the poor targeting ability of CPT and IR820 while exhibiting significant growth inhibitory effects on CRC cells. Mechanistically, to offset the oxidative stress created by the broken SeSe bonds, endogenous GSH was continuously depleted, which inactivated GPX4 to accumulate lipid peroxides and induce ferroptosis. Concurrently, exogenously administered linoleic acid was oxidized under photothermal conditions, resulting in an increase in LPO accumulation. With the breakdown of the oxidative stress defense system, chemotherapeutic efficacy could be effectively enhanced. In combination with photoacoustic imaging, the nanoplatform could eradicate solid tumors by means of ferroptosis-sensitized chemotherapy. This study indicates that chemotherapy involving a ferroptosis mechanism is a viable method for the treatment of CRC.