Dual GSH-exhausting sorafenib loaded manganese-silica nanodrugs for inducing the ferroptosis of hepatocellular carcinoma cells

Targeting the regulation of iron homeostasis as a potential therapeutic strategy for nonalcoholic fatty liver disease

With aging and the increasing incidence of obesity, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD mainly includes simple hepatic steatosis, nonalcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma (HCC). An imbalance in hepatic iron homeostasis is usually associated with the progression of NAFLD and induces iron overload, reactive oxygen species (ROS) production, and lipid peroxide accumulation, which leads to ferroptosis. Ferroptosis is a unique type of programmed cell death (PCD) that is characterized by iron dependence, ROS production and lipid peroxidation. The ferroptosis inhibition systems involved in NAFLD include the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1)/coenzyme Q10 (CoQ10)/nicotinamide adenine dinucleotide phosphate (NADPH) regulatory axes. The main promotion system involved is the acyl-CoA synthetase long-chain family (ACSL4)/arachidonic lipoxygenase 15 (ALOX15) axis. In recent years, an increasing number of studies have focused on the multiple roles of iron homeostasis imbalance and ferroptosis in the progression of NAFLD. This review highlights the latest studies about iron homeostasis imbalance- and ferroptosis-associated NAFLD, mainly including the physiology and pathophysiology of hepatic iron metabolism, hepatic iron homeostasis imbalance during the development of NAFLD, and key regulatory molecules and roles of hepatic ferroptosis in NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.

Breaking the Barriers of Therapy Resistance: Harnessing Ferroptosis for Effective Hepatocellular Carcinoma Therapy

Ferroptosis is a type of cell death that relies on iron and is distinguished by the occurrence of lipid peroxidation and the buildup of reactive oxygen species. Ferroptosis has been demonstrated to have a significant impact on the advancement and resistance to treatment of hepatocellular carcinoma (HCC), thereby highlighting its potential as a viable therapeutic target. Ferroptosis was observed in HCC tissues in contrast to normal liver tissue. The inhibition of ferroptosis has been found to increase the viability of HCC cells and decrease their susceptibility to various anticancer therapies, including chemotherapy, radiotherapy, and immune checkpoint blockade. The administration of drugs that directly modulate ferroptosis regulators or induce excessive production of lipid-reactive oxygen species has demonstrated the potential to enhance the responsiveness of drug-resistant HCC cells to treatment. However, the precise mechanism underlying this phenomenon remains ambiguous. This review presents a comprehensive overview of the crucial role played by ferroptosis in enhancing the efficacy of treatment for hepatocellular carcinoma (HCC). The main aim of this study is to examine the feasibility of utilizing ferroptosis as a therapeutic approach to improve the efficacy of HCC treatment and overcome drug resistance.

Advance on combination therapy strategies based on biomedical nanotechnology induced ferroptosis for cancer therapeutics

Globally, cancer is a serious health problem. It is unfortunate that current anti-cancer strategies are insufficiently specific and damage the normal tissues. There's urgent need for development of new anti-cancer strategies. More recently, increasing attention has been paid to the new application of ferroptosis and nano materials in cancer research. Ferroptosis, a condition characterized by excessive reactive oxygen species-induced lipid peroxidation, as a new programmed cell death mode, exists in the process of a number of diseases, including cancers, neurodegenerative disease, cerebral hemorrhage, liver disease, and renal failure. There is growing evidence that inducing ferroptosis has proven to be an effective strategy against a variety of chemo-resistant cancer cells. Nano-drug delivery system based on nanotechnology provides a highly promising platform with the benefits of precise control of drug release and reduced toxicity and side effects. This paper reviews the latest advances of combination therapy strategies based on biomedical nanotechnology induced ferroptosis for cancer therapeutics. Given the new chances and challenges in this emerging area, we need more attention to the combination of nanotechnology and ferroptosis in the treatment of cancer in the future.

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.

Recent advancements in nanomaterial-mediated ferroptosis-induced cancer therapy: Importance of molecular dynamics and novel strategies

Ferroptosis is a novel type of controlled cell death resulting from an imbalance between oxidative harm and protective mechanisms, demonstrating significant potential in combating cancer. It differs from other forms of cell death, such as apoptosis and necrosis. Molecular therapeutics have hard time playing the long-acting role of ferroptosis induction due to their limited water solubility, low cell targeting capacity, and quick metabolism in vivo. To this end, small molecule inducers based on biological factors have long been used as strategy to induce cell death. Research into ferroptosis and advancements in nanotechnology have led to the discovery that nanomaterials are superior to biological medications in triggering ferroptosis. Nanomaterials derived from iron can enhance ferroptosis induction by directly releasing large quantities of iron and increasing cell ROS levels. Moreover, utilizing nanomaterials to promote programmed cell death minimizes the probability of unfavorable effects induced by mutations in cancer-associated genes such as RAS and TP53. Taken together, this review summarizes the molecular mechanisms involved in ferroptosis along with the classification of ferroptosis induction. It also emphasized the importance of cell organelles in the control of ferroptosis in cancer therapy. The nanomaterials that trigger ferroptosis are categorized and explained. Iron-based and noniron-based nanomaterials with their characterization at the molecular and cellular levels have been explored, which will be useful for inducing ferroptosis that leads to reduced tumor growth. Within this framework, we offer a synopsis, which traverses the well-established mechanism of ferroptosis and offers practical suggestions for the design and therapeutic use of nanomaterials.

Understanding the Novel Approach of Nanoferroptosis for Cancer Therapy

As a new form of regulated cell death, ferroptosis has unraveled the unsolicited theory of intrinsic apoptosis resistance by cancer cells. The molecular mechanism of ferroptosis depends on the induction of oxidative stress through excessive reactive oxygen species accumulation and glutathione depletion to damage the structural integrity of cells. Due to their high loading and structural tunability, nanocarriers can escort the delivery of ferro-therapeutics to the desired site through enhanced permeation or retention effect or by active targeting. This review shed light on the necessity of iron in cancer cell growth and the fascinating features of ferroptosis in regulating the cell cycle and metastasis. Additionally, we discussed the effect of ferroptosis-mediated therapy using nanoplatforms and their chemical basis in overcoming the barriers to cancer therapy.

Co-Delivery of siNRF2 and Sorafenib by a "Click" Dual Functioned Hyperbranched Nanocarrier for Synergistically Inducing Ferroptosis in Hepatocellular Carcinoma

In the course of antitumor therapy, the complex tumor microenvironment and drug-mediated changes in cell signaling and biological processes lead to drug resistance. The effect of sorafenib is greatly limited by the specific tumor microenvironment induced by antiangiogenic therapy and ferroptosis resistance induced by the upregulation of nuclear factor erythroid-2 related factor 2 (NRF2). In this study, a pH responsive and amphiphilic hyperbranched polyglycerol, HDP, is synthesized based on a co-graft click chemistry pathway. This nano-scale carrier provides excellent drug-loading capacity, storing stability and pH responsibility, and effectively co-delivery of sorafenib and siRNA. Sorafenib and siNRF2 plays a greatly synergistic effect in inducing reactive oxygen species (ROS), iron overloading, depleting glutathione (GSH), and promoting lipid peroxidation. Importantly, verified in two different animal experiments, HDP-ss (HDP loaded with both siNRF2 and sorafenib) presents a superior anti-tumor effect, by achieving a tumor inhibition rate of ≈94%. Thus, HDP can serve as an excellent targeted delivery nanocarrier with good biocompatibility in antitumor therapy, and combined application of siNRF2 effectively improves the antitumor effect of sorafenib by overcoming NRF2-mediated ferroptosis resistance. Taken together, this study provides a novel therapeutic strategy to combat the drug resistance in antiangiogenic therapy and ferroptosis.

Ferroptosis targeting natural compounds as a promising approach for developing potent liver cancer agents

Liver cancer is the second leading cause of cancer-related death worldwide. However, treatment options, including surgical resection, transplantation, and molecular drug therapies, are of limited effectiveness. Recent studies have demonstrated that suppressing ferroptosis might be a pivotal signal for liver cancer initiation, thus providing a new way to combat liver cancer. Ferroptosis is a distinct form of controlled cell death that differs from conventional cell death routes like apoptosis, necrosis, and pyroptosis. It results from intracellular iron overload, which raises iron-dependent reactive oxygen species. This, in turn, leads to the accumulation of lipid peroxides that further result in oxidative damage to cell membranes, disrupt normal functioning, and ultimately speed up the ferroptosis phenomenon. Ferroptosis regulation is intricately linked to cellular physiological processes, encompassing iron metabolism, lipid metabolism, and the equilibrium between oxygen-free radical reactions and lipid peroxidation. This review intends to summarize the natural compounds targeting ferroptosis in liver cancer to offer new therapeutic ideas for liver cancer. Furthermore, it serves as the foundation for identifying and applying chemical medicines and natural chemicals that target ferroptosis to treat liver cancer efficiently.

Drug-Loaded Polydopamine Nanoparticles for Chemo/Photothermal Therapy against Colorectal Cancer Cells

Colorectal cancer (CRC) is a common and deadly malignancy, ranking second in terms of mortality and third in terms of incidence on a global scale. The survival rates for CRC patients are unsatisfactory primarily because of the absence of highly effective clinical strategies. The efficacy of existing CRC treatments, such as chemotherapy (CT), is constrained by issues such as drug resistance and damage to healthy tissues. Alternative approaches such as photothermal therapy (PTT), while offering advantages over traditional therapies, suffer instead from a low efficiency in killing tumor cells when used alone. In this context, nanostructures can efficiently contribute to a selective and targeted treatment. Here, we combined CT and PTT by developing a nanoplatform based on polydopamine nanoparticles (PDNPs), selected for their biocompatibility, drug-carrying capabilities, and ability to produce heat upon exposure to near-infrared (NIR) irradiation. As a chemotherapy drug, sorafenib has been selected, a multikinase inhibitor already approved for clinical use. By encapsulating sorafenib in polydopamine nanoparticles (Sor-PDNPs), we were able to successfully improve the drug stability in physiological media and the consequent uptake by CRC cells, thereby increasing its therapeutic effects. Upon NIR stimulus, Sor-PDNPs can induce a temperature increment of about 10 °C, encompassing both PTT and triggering a localized and massive drug release. Sor-PDNPs were tested on healthy colon cells, showing minimal adverse outcomes; conversely, they demonstrated excellent efficacy against CRC cells, with a strong capability to hinder cancer cell proliferation and induce apoptosis. Obtained findings pave the way to new synergistic chemo-photothermal approaches, maximizing the therapeutic outcomes against CRC while minimizing side effects on healthy cells.

Ferroptosis contributing to cardiomyocyte injury induced by silica nanoparticles via miR-125b-2-3p/HO-1 signaling

BACKGROUND

Amorphous silica nanoparticles (SiNPs) have been gradually proven to threaten cardiac health, but pathogenesis has not been fully elucidated. Ferroptosis is a newly defined form of programmed cell death that is implicated in myocardial diseases. Nevertheless, its role in the adverse cardiac effects of SiNPs has not been described.

RESULTS

We first reported the induction of cardiomyocyte ferroptosis by SiNPs in both in vivo and in vitro. The sub-chronic exposure to SiNPs through intratracheal instillation aroused myocardial injury, characterized by significant inflammatory infiltration and collagen hyperplasia, accompanied by elevated CK-MB and cTnT activities in serum. Meanwhile, the activation of myocardial ferroptosis by SiNPs was certified by the extensive iron overload, declined FTH1 and FTL, and lipid peroxidation. The correlation analysis among detected indexes hinted ferroptosis was responsible for the SiNPs-aroused myocardial injury. Further, in vitro tests, SiNPs triggered iron overload and lipid peroxidation in cardiomyocytes. Concomitantly, altered expressions of TfR, DMT1, FTH1, and FTL indicated dysregulated iron metabolism of cardiomyocytes upon SiNP stimuli. Also, shrinking mitochondria with ridge fracture and ruptured outer membrane were noticed. To note, the ferroptosis inhibitor Ferrostatin-1 could effectively alleviate SiNPs-induced iron overload, lipid peroxidation, and myocardial cytotoxicity. More importantly, the mechanistic investigations revealed miR-125b-2-3p-targeted HO-1 as a key player in the induction of ferroptosis by SiNPs, probably through regulating the intracellular iron metabolism to mediate iron overload and ensuing lipid peroxidation.

CONCLUSIONS

Our findings firstly underscored the fact that ferroptosis mediated by miR-125b-2-3p/HO-1 signaling was a contributor to SiNPs-induced myocardial injury, which could be of importance to elucidate the toxicity and provide new insights into the future safety applications of SiNPs-related nano products.

Biocompatible formulation of a hydrophobic antimicrobial peptide L30 through nanotechnology principles and its potential role in mouse pneumonia model infected with Staphylococcus aureus

Hydrophobic antimicrobial peptide L30, a potential antibiotic candidate, has poor water solubility and hemolytic activity. Herein, a biocompatible nano-formulation composed of liposomes and dendritic mesoporous silica encapsulation (LDMSNs@L30) was constructed for L30 to solve the limits for its clinical development. The characterization, antimicrobial activity and therapeutic effect of LDMSNs@L30 on Staphylococcus aureus 9 (cfr+) infected mice models were investigated. LDMSNs@L30 displayed a smooth, spherical, and monodisperse nanoparticle with a hydrodynamic diameter of 177.40 nm, an encapsulation rate of 56.13%, a loading efficiency of 32.26%, a release rate of 66.5%, and effective slow-release of L30. Compared with free L30, the formulation could significantly increase the solubility of L30 in PBS with the maximum concentration from 8 μg/mL to 2.25 mg/mL and decrease the hemolytic activity of hydrophobic peptide L30 with the HC5 from 65.36 μg/mL to more than 500 μg/mL. The nano delivery system LDMSNs@L30 also exhibited higher therapeutic effects on mice models infected with S. aureus 9 (cfr+) than those of free L30 after 7 days of treatment by reducing the lung inflammation and the inflammatory cytokines levels in plasma, showing better health score and pulmonary pathological improvement. Our research suggests that nano-formulation can be expected to be a promising strategy for peptide drugs in therapeutic applications.

Ferroptosis-related gene glutathione peroxidase 4 promotes reprogramming of glucose metabolism via Akt-mTOR axis in intrahepatic cholangiocarcinoma

The role of the ferroptosis-related gene glutathione peroxidase 4 (GPX4) in oncology has been extensively investigated. However, the clinical implications of GPX4 in patients with intrahepatic cholangiocarcinoma (ICC) remain unknown. This study aimed to evaluate the prognostic impact of GPX4 and its underlying molecular mechanisms in patients with ICC. Fifty-seven patients who underwent surgical resection for ICC between 2010 and 2017 were retrospectively analyzed. Based on the immunohistochemistry, patients were divided into GPX4 high (n = 15) and low (n = 42) groups, and clinical outcomes were assessed. Furthermore, the roles of GPX4 in cell proliferation, migration and gene expression were analyzed in ICC cell lines in vitro and in vivo. The results from clinical study showed that GPX4 high group showed significant associations with high SUVmax on 18F-fluorodeoxyglucose-positron emission tomography (≥8.0, P = 0.017), multiple tumors (P = 0.004), and showed glucose transporter 1 (GLUT1) high expression with a trend toward significance (P = 0.053). Overall and recurrence-free survival in the GPX4 high expression group were significantly worse than those in the GPX4 low expression group (P = 0.038 and P < 0.001, respectively). In the experimental study, inhibition of GPX4 attenuated cell proliferation and migration in ICC cell lines. Inhibition of GPX4 also decreased the expression of glucose metabolism-related genes, such as GLUT1 or HIF1α. Mechanistically, these molecular changes are regulated in Akt-mechanistic targets of rapamycin axis. In conclusion, this study suggested the pivotal value of GPX4 serving as a prognostic marker for patients with ICC. Furthermore, GPX4 can mediate glucose metabolism of ICC.

Advances in Ferroptosis-Inducing Agents by Targeted Delivery System in Cancer Therapy

Currently, cancer remains one of the most significant threats to human health. Treatment of most cancers remains challenging, despite the implementation of diverse therapies in clinical practice. In recent years, research on the mechanism of ferroptosis has presented novel perspectives for cancer treatment. Ferroptosis is a regulated cell death process caused by lipid peroxidation of membrane unsaturated fatty acids catalyzed by iron ions. The rapid development of bio-nanotechnology has generated considerable interest in exploiting iron-induced cell death as a new therapeutic target against cancer. This article provides a comprehensive overview of recent advancements at the intersection of iron-induced cell death and bionanotechnology. In this respect, the mechanism of iron-induced cell death and its relation to cancer are summarized. Furthermore, the feasibility of a nano-drug delivery system based on iron-induced cell death for cancer treatment is introduced and analyzed. Secondly, strategies for inducing iron-induced cell death using nanodrug delivery technology are discussed, including promoting Fenton reactions, inhibiting glutathione peroxidase 4, reducing low glutathione levels, and inhibiting system Xc-. Additionally, the article explores the potential of combined treatment strategies involving iron-induced cell death and bionanotechnology. Finally, the application prospects and challenges of iron-induced nanoagents for cancer treatment are discussed.

Crosstalk between ferroptosis and cuproptosis: From mechanism to potential clinical application

Ferroptosis and cuproptosis, regulated forms of cell death resulting from metal ion accumulation, are closely related in terms of occurrence, cell metabolism, signaling pathways, and drug resistance. Notably, it is now understood that these processes play crucial roles in regulating physiological and pathological processes, especially in tumor development. Consequently, ferroptosis and cuproptosis have gained increasing significance as potential targets for anti-cancer drug development. This article systematically outlines the molecular mechanisms and cross-talk components of both ferroptosis and cuproptosis, elucidating their impacts on cancer. Furthermore, it investigates the clinical perspective of targeted ferroptosis and cuproptosis in cancer chemotherapy, immunotherapy, and radiotherapy. Our discussion extends to a comparative analysis of nanoparticles developed based on the mechanisms of ferroptosis and cuproptosis in cancer, contrasting them with current conventional therapies. Opportunities and challenges in cancer treatment are explored, emphasizing the potential therapeutic direction of co-targeting ferroptosis and cuproptosis. The article also attempts to analyze the clinical applications of this co-targeting approach for cancer treatment while summarizing the existing barriers that require overcoming.

Cucurbitacin B and erastin co-treatment synergistically induced ferroptosis in breast cancer cells via altered iron-regulating proteins and lipid peroxidation

Ferroptosis is a unique type of cell death which co-exists with elevated iron, suppressed antioxidative function and increased lipid peroxidation. Recent studies have shown that cancer cells are particularly susceptible to the compounds with ferroptotic activities. Cucurbitacin B (CuB) is a triterpenoid with potent biological properties. It has been demonstrated to induce apoptosis and inhibit metastasis in cancer cells. However, the underlying mechanism of the compound is still not fully understood. In the present study, we investigated the ferroptotic effect of CuB in breast cancer cells and evaluated the impact of its combination with erastin, a ferroptosis inducer. In this regard, MTT assay was performed to analyze cell viability. Lipid peroxidation, oxidative stress and the cellular antioxidant capacity were determined with relevant kits. The expression of ferroptotic proteins were analyzed by western blotting. The results indicated that the combined treatment of CuB and erastin activated the ferroptotic pathways significantly in MCF-7 and MDA-MB-231 breast cancer cells. More importantly, the combination treatment altered the expression of iron-related proteins IREB2 and FPN1. In conclusion, this study demonstrated the ferroptotic potential of CuB in breast cancer cells for the first time, and revealed its impact on the expression of iron-regulating proteins.

pH-Responsive Sorafenib/Iron-Co-Loaded Mesoporous Polydopamine Nanoparticles for Synergistic Ferroptosis and Photothermal Therapy

Ferroptosis has attracted significant attention as a new mechanism of cell death. Sorafenib (SRF) is widely considered a prototypical ferroptosis-inducing drug, particularly for liver cancer treatment. However, the low solubility and hydrophobic nature of SRF, along with the absence of synergistic therapeutic strategies, still limit its application in cancer treatment. Herein, we report a dual therapeutic method incorporating photothermal therapy and ferroptosis by using Fe-doped mesoporous polydopamine nanoparticles (Fe-mPDA@SRF-TPP) as a carrier for loading SRF and targeting triphenylphosphine (TPP). SRF molecules are efficiently encapsulated within the polydopamine nanospheres with a high loading ratio (80%) attributed to the porosity of Fe-mPDA, and the inherent biocompatibility and hydrophilicity of Fe-mPDA@SRF-TPP facilitate the transport of SRF to the target cancer cells. Under the external stimuli of acidic environment (pH 5.0), glutathione (GSH), and laser irradiation, Fe-mPDA@SRF-TPP shows sustained release of SRF and Fe ions with the ratio of 72 and 50% within 48 h. Fe-mPDA@SRF-TPP nanoparticles induce intracellular GSH depletion, inhibit glutathione peroxidase 4 (GPX4) activity, and generate hydroxyl radicals, all of which are essential components of the therapeutic ferroptosis process for killing MDA-MB-231 cancer cells. Additionally, the excellent near-infrared (NIR) light absorption of Fe-mPDA@SRF-TPP nanoparticles demonstrates their capability for photothermal therapy and further enhances the therapeutic efficiency. Therefore, this nanosystem provides a multifunctional therapeutic platform that overcomes the therapeutic limitations associated with standalone ferroptosis and enhances the therapeutic efficacy of SRF for breast cancer.

Iron accumulation and lipid peroxidation: implication of ferroptosis in hepatocellular carcinoma

Ferroptosis is a type of controlled cell death caused by lipid peroxidation, which results in the rupture of the cell membrane. ferroptosis has been repeatedly demonstrated over the past ten years to be a significant factor in a number of diseases. The liver is a significant iron storage organ, thus ferroptosis will have great potential in the treatment of liver diseases. Ferroptosis is particularly prevalent in HCC. In the opening section of this article, we give a general summary of the pertinent molecular mechanisms, signaling pathways, and associated characteristics of ferroptosis. The primary regulating mechanisms during ferroptosis are then briefly discussed, and we conclude by summarizing the development of a number of novel therapeutic strategies used to treat HCC in recent years. Ferroptosis is a crucial strategy for the treatment of HCC and offers new perspectives on the treatment of liver cancer.

The application of nanoparticles based on ferroptosis in cancer therapy

Ferroptosis is a new form of non-apoptotic programmed cell death. Due to its effectiveness in cancer treatment, there are increasing studies on the application of nanoparticles based on ferroptosis in cancer therapy. In this paper, we present a summary of the latest progress in nanoparticles based on ferroptosis for effective tumor therapy. We also describe the combined treatment of ferroptosis with other therapies, including chemotherapy, radiotherapy, phototherapy, immunotherapy, and gene therapy. This summary of drug delivery systems based on ferroptosis aims to provide a basis and inspire opinions for researchers concentrating on exploring this field. Finally, we present some prospects and challenges for the application of nanotherapies to clinical treatment by promoting ferroptosis in cancer cells.

Enhancing anti-cancer potential by delivering synergistic drug combinations via phenylboronic acid modified PLGA nanoparticles through ferroptosis-based therapy

In this study, we investigated the potential of the sorafenib (SOR) and simvastatin (SIM) combination to induce ferroptosis-mediated cancer therapy. To enhance targeted drug delivery, we encapsulated the SOR + SIM combination within 4-carboxy phenylboronic acid (CPBA) modified PLGA nanoparticles (CPBA-PLGA(SOR + SIM)-NPs). The developed CPBA-PLGA(SOR + SIM)-NPs exhibited a spherical shape with a size of 213.1 ± 10.9 nm, a PDI of 0.22 ± 0.03, and a Z-potential of -22.9 ± 3.2 mV. Notably, these nanoparticles displayed faster drug release at acidic pH compared to physiological pH. In cellular experiments, CPBA-PLGA(SOR + SIM)-NPs demonstrated remarkable improvements, leading to a 2.51, 2.69, and 2.61-fold decrease in IC50 compared to SOR alone, and a 7.50, 16.71, and 5.11-fold decrease in IC50 compared to SIM alone in MDA-MB-231, A549, and HeLa cells, respectively. Furthermore, CPBA-PLGA(SOR + SIM)-NPs triggered a reduction in glutathione (GSH) levels, an increase in malondialdehyde (MDA) levels, and mitochondrial membrane depolarization in all three cell lines. Pharmacokinetic evaluation revealed a 2.50- and 2.63-fold increase in AUC0-∞, as well as a 1.53- and 2.46-fold increase in mean residence time (MRT) for SOR and SIM, respectively, compared to the free drug groups. Notably, the CPBA-PLGA(SOR + SIM)-NPs group exhibited significant reduction in tumor volume, approximately 9.17, 2.45, and 1.63-fold lower than the control, SOR + SIM, and PLGA(SOR + SIM)-NPs groups, respectively. Histological examination and biomarker analysis showed no significant differences compared to the control group, suggesting the biocompatibility of the developed particles for in-vivo applications. Altogether, our findings demonstrate that CPBA-PLGA(SOR + SIM)-NPs hold tremendous potential as an efficient drug delivery system for inducing ferroptosis, providing a promising therapeutic option for cancer treatment.

Targeting metabolic reprogramming in hepatocellular carcinoma to overcome therapeutic resistance: A comprehensive review

Hepatocellular carcinoma (HCC) poses a heavy burden on human health with high morbidity and mortality rates. Systematic therapy is crucial for advanced and mid-term HCC, but faces a significant challenge from therapeutic resistance, weakening drug effectiveness. Metabolic reprogramming has gained attention as a key contributor to therapeutic resistance. Cells change their metabolism to meet energy demands, adapt to growth needs, or resist environmental pressures. Understanding key enzyme expression patterns and metabolic pathway interactions is vital to comprehend HCC occurrence, development, and treatment resistance. Exploring metabolic enzyme reprogramming and pathways is essential to identify breakthrough points for HCC treatment. Targeting metabolic enzymes with inhibitors is key to addressing these points. Inhibitors, combined with systemic therapeutic drugs, can alleviate resistance, prolong overall survival for advanced HCC, and offer mid-term HCC patients a chance for radical resection. Advances in metabolic research methods, from genomics to metabolomics and cells to organoids, help build the HCC metabolic reprogramming network. Recent progress in biomaterials and nanotechnology impacts drug targeting and effectiveness, providing new solutions for systemic therapeutic drug resistance. This review focuses on metabolic enzyme changes, pathway interactions, enzyme inhibitors, research methods, and drug delivery targeting metabolic reprogramming, offering valuable references for metabolic approaches to HCC treatment.

From synergy to resistance: Navigating the complex relationship between sorafenib and ferroptosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a major global health burden, and sorafenib, a multi-kinase inhibitor, has shown effectiveness in the treatment of HCC and is considered as the first-line therapy for advanced HCC. However, the response to sorafenib varies among patients, and the development of drug resistance poses a prevalent obstacle. Ferroptosis, a newly characterized form of cell death featured by iron-dependent lipid peroxidation, has emerged as a critical player in the reaction to sorafenib therapy in HCC. The induction of ferroptosis has been shown to augment the anticancer benefits of sorafenib. However, it has also been observed to contribute to sorafenib resistance. This review presents a comprehensive and thorough analysis that elucidates the intricate relationship between ferroptosis and sorafenib over recent years, aiming to formulate effective therapeutic approaches for liver cancer. Based on this exploration, we propose innovative strategies intended to overcome sorafenib resistance via targeted modulation of ferroptosis.

Synergistic anticancer therapy via ferroptosis using modified bovine serum albumin nanoparticles loaded with sorafenib and simvastatin

Ferroptosis is a non-apoptotic cell death pathway characterized by the accumulation of lipid-peroxy radicals within the affected cells. Here, we investigate the synergistic capacity of sorafenib (SOR) and simvastatin (SIM) to trigger ferroptosis for cancer therapy. For precise in-vivo delivery, SOR + SIM was ratiometrically loaded in bovine serum albumin nanoparticles (BSA-NPs) modified with 4-carboxy phenylboronic acid (CPBA). The developed CPBA-BSA(SOR + SIM)-NPs revealed size of 175.2 ± 12.8 nm, with PDI of 0.22 ± 0.03 and Z-potential of -29.6 ± 4.8 mV. Significantly, CPBA-BSA(SOR + SIM)-NPs exhibited > 2 and > 5-fold reduction in IC50 values compared to individual SOR and SIM treatments respectively, in all tested cell lines. Moreover, CPBA-BSA(SOR + SIM)-NPs treated cells exhibited decrease in glutathione levels, increase in malonaldehyde levels and depolarization of mitochondrial membrane potential (JC-1 assay). Pharmacokinetic analysis revealed enhanced AUC0-∞ and MRT levels for SOR and SIM when administered as CPBA-BSA(SOR + SIM)-NPs compared to free drugs. Crucially, in in-vivo experiments, CPBA-BSA(SOR + SIM)-NPs led to a significant reduction in tumor volume compared to various control groups. Histological and biomarker analyses underscore their biocompatibility for clinical applications. In conclusion, this study highlights the potential of CPBA-BSA(SOR + SIM)-NPs as a promising strategy for inducing ferroptosis in cancer cells, concurrently improving drug delivery and therapeutic efficacy. This approach opens new avenues in cancer treatment.

Ferroptosis: a new promising target for hepatocellular carcinoma therapy

Hepatocellular carcinoma (HCC) is the sixed most common malignant tumor in the world. The study for HCC is mired in the predicament confronted with the difficulty of early diagnosis and high drug resistance, the survival rate of patients with HCC being low. Ferroptosis, an iron-dependent cell death, has been discovered in recent years as a cell death means with tremendous potential to fight against cancer. The in-depth researches for iron metabolism, lipid peroxidation and dysregulation of antioxidant defense have brought about tangible progress in the firmament of ferroptosis with more and more results showing close connections between ferroptosis and HCC. The potential role of ferroptosis has been widely used in chemotherapy, immunotherapy, radiotherapy, and nanotherapy, with the development of various new drugs significantly improving the prognosis of patients. Based on the characteristics and mechanisms of ferroptosis, this article further focuses on the main signaling pathways and promising treatments of HCC, envisioning that existing problems in regard with ferroptosis and HCC could be grappled with in the foreseeable future.

Self-engineered binary nanoassembly enabling closed-loop glutathione depletion-amplified tumor ferroptosis

Ferroptosis has emerged as a promising target for anticancer treatment, comprising iron-dependent lipid peroxidation and excessive accumulation of reactive oxygen species. Given that glutathione (GSH) overproduced in tumor cells antagonizes the cellular oxidation system, the reduction of GSH production has been extensively explored to induce ferroptosis. However, reducing GSH production alone is insufficient to trigger an intense lipid peroxidation storm. It is highly desirable to achieve systemic GSH depletion through simultaneous production and consumption intervention. Herein, we propose a bidirectional blockage strategy for closed-loop GSH depletion-amplified tumor ferroptosis. Sorafenib (Sor) and gambogic acid (GA) were elaborately fabricated as a self-engineered carrier-free nanoassembly without any nanocarrier materials. The PEGylated dual-drug nanoassembly enables favorable co-delivery and tumor-specific release of Sor and GA. Notably, a closed-loop GSH depletion is observed as a result of a Sor-induced decrease in GSH production and GA-accelerated GSH consumption in vitro and in vivo. As expected, this uniquely engineered dual-drug nanoassembly demonstrates vigorous antitumor activity in 4T1 breast tumor-bearing mice. This study presents a novel nanotherapeutic modality for ferroptosis-driven cancer treatment.

Synergistic Amplification of Ferroptosis with Liposomal Oxidation Catalyst and Gpx4 Inhibitor for Enhanced Cancer Therapy

As a distinctly different way from apoptosis, ferroptosis can cause cell death through excessive accumulation of lipid peroxide (LPO) and show great potential for cancer therapy. However, efficient strategies for ferroptosis therapy are still facing great challenges, mainly due to insufficient endogenous H2 O2 or relatively high pH value for Fenton reaction-dependent ferroptosis, and the high redox level of tumor cells attenuates the oxidation therapy. Herein, an efficient lipid-based delivery system to load oxidation catalyst and glutathione peroxidase 4 (Gpx4) inhibitor is orchestrated, intending to amplify Fenton reaction-independent ferroptosis by bidirectional regulation of LPO accumulation. Ferric ammonium citrate (FAC), Gpx4 inhibitor sorafenib (SF), and unsaturated lipids are constructed into mPEG2K -DSPE-modified liposomes (Lip@SF&FAC). Influenced by the high level of intratumoral glutathione, FAC can be converted into Fe2+ , and subsequently the formed iron redox pair (Fe2+ /Fe3+ ) catalyzes unsaturated phospholipids of liposomes into LPO via a Fenton reaction-independent manner. Meanwhile, SF can downregulate LPO reduction by inhibiting Gpx4 activation. In vitro and in vivo antitumor experiments show that Lip@SF&FAC induces massive LPO accumulation in tumor cells and ultimately exhibits strong tumor-killing ability with negligible side effect. Consequently, this two-pronged approach provides a new ferroptosis strategy for predominant LPO accumulation and enhanced cancer therapy.

Targeting ferroptosis opens new avenues for the development of novel therapeutics

Ferroptosis is an iron-dependent form of regulated cell death with distinct characteristics, including altered iron homeostasis, reduced defense against oxidative stress, and abnormal lipid peroxidation. Recent studies have provided compelling evidence supporting the notion that ferroptosis plays a key pathogenic role in many diseases such as various cancer types, neurodegenerative disease, diseases involving tissue and/or organ injury, and inflammatory and infectious diseases. Although the precise regulatory networks that underlie ferroptosis are largely unknown, particularly with respect to the initiation and progression of various diseases, ferroptosis is recognized as a bona fide target for the further development of treatment and prevention strategies. Over the past decade, considerable progress has been made in developing pharmacological agonists and antagonists for the treatment of these ferroptosis-related conditions. Here, we provide a detailed overview of our current knowledge regarding ferroptosis, its pathological roles, and its regulation during disease progression. Focusing on the use of chemical tools that target ferroptosis in preclinical studies, we also summarize recent advances in targeting ferroptosis across the growing spectrum of ferroptosis-associated pathogenic conditions. Finally, we discuss new challenges and opportunities for targeting ferroptosis as a potential strategy for treating ferroptosis-related diseases.

Understanding sorafenib-induced ferroptosis and resistance mechanisms: Implications for cancer therapy

Sorafenib is an important first-line treatment option for liver cancer due to its well-characterized safety profile. While novel first-line drugs may have better efficacy than Sorafenib, they also have limitations such as worse safety and cost-effectiveness. In addition to inducing apoptosis, Sorafenib can also trigger ferroptosis, which has recently been recognized as an immunogenic cell death, unleashing new possibilities for cancer treatment. However, resistance to Sorafenib-induced ferroptosis remains a major challenge. To overcome this resistance and augment the efficacy of Sorafenib, a wide range of nanomedicines has been developed to amplify its pro-ferroptotic effects. This review highlights the mechanisms underlying Sorafenib-triggered ferroptosis and its resistance, and outlines innovative strategies, particularly nanomedicines, to overcome ferroptosis resistance. Moreover, we summarize molecular biomarkers that signify resistance to Sorafenib-mediated ferroptosis, which can assist in predicting therapeutic outcomes.

Exploring Sorafenib and Simvastatin Combination for Ferroptosis-Induced Cancer Treatment: Cytotoxicity Screening, In Vivo Efficacy, and Safety Assessment

Ferroptosis, a pathway dependent on oxygen and iron catalysts, holds promise as a therapeutic approach for cancer treatment due to its manageable regulation, direct control, and immunogenic properties. The sensitivity of cancer cells to ferroptosis induction varies based on their metabolic, genetic, and signalling pathways, prompting the use of combination therapy. In this study, we conducted a screening of drug combinations, including sorafenib (SOR) with simvastatin (SIM), phenethyl isothiocyanate, and trigonelline, in MDA-MB-231, A549, and HeLa cells to assess their cytotoxicity. The SOR-SIM combination exhibited a synergistic effect in MDA-MB-231, A549, and HeLa cells, with calculated CI values of ~ 0.66, 0.53, and 0.59, respectively. Furthermore, co-treatment with ferrostatin-1 resulted in a concentration-dependent increase in the IC50 values. Additionally, SOR + SIM demonstrated a significant reduction in GSH levels, an increase in MDA levels, and mitochondrial membrane depolarization across all three cell lines, indicating their ferroptosis inducing potential. In-vivo studies showed a significant reduction in tumor volume by 3.53-, 2.55-, and 1.47-fold compared to control, SIM, and SOR, respectively. Toxicity assessments revealed insignificant changes in biomarker levels and no observable deformations in isolated organs, except for erythrocyte shrinkage and membrane scrambling effects caused by the SOR + SIM combination. Overall, our findings highlight the potential of the SOR + SIM combination as an effective strategy for cancer treatment, emphasizing the importance of further research in targeted drug delivery systems to ensure its safety.

Noncoding RNAs in cancer ferroptosis: From biology to clinical opportunity

Ferroptosis is a recently discovered pattern of programmed cell death that is nonapoptotic and irondependent. It is involved in lipid peroxidation dependent on reactive oxygen species. Ferroptosis has been verified to play a crucial regulatory role in a variety of pathological courses of disease, in particularly cancer. Emerging research has highlighted the potential of ferroptosis in tumorigenesis, cancer development and resistance to chemotherapy. However, the regulatory mechanism of ferroptosis remains unclear, which limits the application of ferroptosis in cancer treatment. Noncoding RNAs (ncRNAs) are noncoding transcripts that regulate gene expression in various ways to affect the malignant phenotypes of cancer cells. At present, the biological function and underlying regulatory mechanism of ncRNAs in cancer ferroptosis have been partially elucidated. Herein, we summarize the current knowledge of the central regulatory network of ferroptosis, with a focus on the regulatory functions of ncRNAs in cancer ferroptosis. The clinical application and prospects of ferroptosis-related ncRNAs in cancer diagnosis, prognosis and anticancer therapies are also discussed. Elucidating the function and mechanism of ncRNAs in ferroptosis, along with assessing the clinical significance of ferroptosis-related ncRNAs, provides new perspectives for understanding cancer biology and treatment approaches, which may benefit numerous cancer patients in the future.

Ferroptosis, Necroptosis, and Pyroptosis in Gastrointestinal Cancers: The Chief Culprits of Tumor Progression and Drug Resistance

In recent years, the incidence of gastrointestinal cancers is increasing, particularly in the younger population. Effective treatment is crucial for improving patients' survival outcomes. Programmed cell death, regulated by various genes, plays a fundamental role in the growth and development of organisms. It is also critical for maintaining tissue and organ homeostasis and takes part in multiple pathological processes. In addition to apoptosis, there are other types of programmed cell death, such as ferroptosis, necroptosis, and pyroptosis, which can induce severe inflammatory responses. Notably, besides apoptosis, ferroptosis, necroptosis, and pyroptosis also contribute to the occurrence and development of gastrointestinal cancers. This review aims to provide a comprehensive summary on the biological roles and molecular mechanisms of ferroptosis, necroptosis, and pyroptosis, as well as their regulators in gastrointestinal cancers and hope to open up new paths for tumor targeted therapy in the near future.

Iron accumulation and lipid peroxidation: implication of ferroptosis in diabetic cardiomyopathy

Diabetic cardiomyopathy (DC) is a serious heart disease caused by diabetes. It is unrelated to hypertension and coronary artery disease and can lead to heart insufficiency, heart failure and even death. Currently, the pathogenesis of DC is unclear, and clinical intervention is mainly symptomatic therapy and lacks effective intervention objectives. Iron overdose mediated cell death, also known as ferroptosis, is widely present in the physiological and pathological processes of diabetes and DC. Iron is a key trace element in the human body, regulating the metabolism of glucose and lipids, oxidative stress and inflammation, and other biological processes. Excessive iron accumulation can lead to the imbalance of the antioxidant system in DC and activate and aggravate pathological processes such as excessive autophagy and mitochondrial dysfunction, resulting in a chain reaction and accelerating myocardial and microvascular damage. In-depth understanding of the regulating mechanisms of iron metabolism and ferroptosis in cardiovascular vessels can help improve DC management. Therefore, in this review, we summarize the relationship between ferroptosis and the pathogenesis of DC, as well as potential intervention targets, and discuss and analyze the limitations and future development prospects of these targets.

Sorafenib-Based Drug Delivery Systems: Applications and Perspectives

As a Food and Drug Administration (FDA)-approved molecular-targeted chemotherapeutic drug, sorafenib (SF) can inhibit angiogenesis and tumor cell proliferation, leading to improved patient overall survival of hepatocellular carcinoma (HCC). In addition, SF is an oral multikinase inhibitor as a single-agent therapy in renal cell carcinoma. However, the poor aqueous solubility, low bioavailability, unfavorable pharmacokinetic properties and undesirable side effects (anorexia, gastrointestinal bleeding, and severe skin toxicity, etc.) seriously limit its clinical application. To overcome these drawbacks, the entrapment of SF into nanocarriers by nanoformulations is an effective strategy, which delivers SF in a target tumor with decreased adverse effects and improved treatment efficacy. In this review, significant advances and design strategies of SF nanodelivery systems from 2012 to 2023 are summarized. The review is organized by type of carriers including natural biomacromolecule (lipid, chitosan, cyclodextrin, etc.); synthetic polymer (poly(lactic-co-glycolic acid), polyethyleneimine, brush copolymer, etc.); mesoporous silica; gold nanoparticles; and others. Co-delivery of SF and other active agents (glypican-3, hyaluronic acid, apolipoprotein peptide, folate, and superparamagnetic iron oxide nanoparticles) for targeted SF nanosystems and synergistic drug combinations are also highlighted. All these studies showed promising results for targeted treatment of HCC and other cancers by SF-based nanomedicines. The outlook, challenges and future opportunities for the development of SF-based drug delivery are presented.

A pH-responsive liposomal nanoplatform for co-delivery of a Pt(IV) prodrug and cinnamaldehyde for effective tumor therapy

Introduction: The tumor microenvironment (TME) is mainly characterized by abnormally elevated intracellular redox levels and excessive oxidative stress. However, the balance of the TME is also very fragile and susceptible to be disturbed by external factors. Therefore, several researchers are now focusing on intervening in redox processes as a therapeutic strategy to treat tumors. Here, we have developed a liposomal drug delivery platform that can load a Pt(IV) prodrug (DSCP) and cinnamaldehyde (CA) into a pH-responsive liposome to enrich more drugs in the tumor region for better therapeutic efficacy through enhanced permeability and retention effect. Methods: Using the glutathione-depleting properties of DSCP together with the ROS-generating properties of cisplatin and CA, we synergistically altered ROS levels in the tumor microenvironment to damage tumor cells and achieve anti-tumor effects in vitro. Results: A liposome loaded with DSCP and CA was successfully established, and this liposome effectively increased the level of ROS in the tumor microenvironment and achieved effective killing of tumor cells in vitro. Conclusion: In this study, novel liposomal nanodrugs loaded with DSCP and CA provided a synergistic strategy between conventional chemotherapy and disruption of TME redox homeostasis, leading to a significant increase in antitumor effects in vitro.

Inaugurating a novel adjuvant therapy in urological cancers: Ferroptosis

Ferroptosis, a distinctive form of programmed cell death, is involved in numerous diseases with specific characteristics, including certain cell morphology, functions, biochemistry, and genetics, that differ from other forms of programmed cell death, such as apoptosis. Many studies have explored ferroptosis and its associated mechanisms, drugs, and clinical applications in diseases such as kidney injury, stroke, ischemia-reperfusion injury, and prostate cancer. In this review, we summarize the regulatory mechanisms of some ferroptosis inducers, such as enzalutamide and erastin. These are current research focuses and have already been studied extensively. In summary, this review focuses on the use of ferroptosis induction as a therapeutic strategy for treating tumors of the urinary system.

Ferroptosis in gastrointestinal cancer: From mechanisms to implications

Ferroptosis is a form of regulated cell death that is initiated by excessive lipid peroxidation that results in plasma membrane damage and the release of damage-associated molecular patterns. In recent years, ferroptosis has gained significant attention in cancer research due to its unique mechanism compared to other forms of regulated cell death, especially caspase-dependent apoptotic cell death. Gastrointestinal (GI) cancer encompasses malignancies that arise in the digestive tract, including the stomach, intestines, pancreas, colon, liver, rectum, anus, and biliary system. These cancers are a global health concern, with high incidence and mortality rates. Despite advances in medical treatments, drug resistance caused by defects in apoptotic pathways remains a persistent challenge in the management of GI cancer. Hence, exploring the role of ferroptosis in GI cancers may lead to more efficacious treatment strategies. In this review, we provide a comprehensive overview of the core mechanism of ferroptosis and discuss its function, regulation, and implications in the context of GI cancers.

Ferroptosis: From Basic Research to Clinical Therapeutics in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and highly heterogeneous malignancies worldwide. Despite the rapid development of multidisciplinary treatment and personalized precision medicine strategies, the overall survival of HCC patients remains poor. The limited survival benefit may be attributed to difficulty in early diagnosis, the high recurrence rate and high tumor heterogeneity. Ferroptosis, a novel mode of cell death driven by iron-dependent lipid peroxidation, has been implicated in the development and therapeutic response of various tumors, including HCC. In this review, we discuss the regulatory network of ferroptosis, describe the crosstalk between ferroptosis and HCC-related signaling pathways, and elucidate the potential role of ferroptosis in various treatment modalities for HCC, such as systemic therapy, radiotherapy, immunotherapy, interventional therapy and nanotherapy, and applications in the diagnosis and prognosis of HCC, to provide a theoretical basis for the diagnosis and treatment of HCC to effectively improve the survival of HCC patients.

Iron as a therapeutic target in chronic liver disease

It was clearly realized more than 50 years ago that iron deposition in the liver may be a critical factor in the development and progression of liver disease. The recent clarification of ferroptosis as a specific form of regulated hepatocyte death different from apoptosis and the description of ferritinophagy as a specific variation of autophagy prompted detailed investigations on the association of iron and the liver. In this review, we will present a brief discussion of iron absorption and handling by the liver with emphasis on the role of liver macrophages and the significance of the iron regulators hepcidin, transferrin, and ferritin in iron homeostasis. The regulation of ferroptosis by endogenous and exogenous mod-ulators will be examined. Furthermore, the involvement of iron and ferroptosis in various liver diseases including alcoholic and non-alcoholic liver disease, chronic hepatitis B and C, liver fibrosis, and hepatocellular carcinoma (HCC) will be analyzed. Finally, experimental and clinical results following interventions to reduce iron deposition and the promising manipulation of ferroptosis will be presented. Most liver diseases will be benefited by ferroptosis inhibition using exogenous inhibitors with the notable exception of HCC, where induction of ferroptosis is the desired effect. Current evidence mostly stems from in vitro and in vivo experimental studies and the need for well-designed future clinical trials is warranted.

Ferroptosis: challenges and opportunities for nanomaterials in cancer therapy

Ferroptosis, a completely new form of regulated cell death, is mainly caused by an imbalance between oxidative damage and reductive protection and has shown great anti-cancer potential. However, existing small-molecule ferroptosis inducers have various limitations, such as poor water solubility, drug resistance and low targeting ability, hindering their clinical applications. Nanotechnology provides new opportunities for ferroptosis-driven tumor therapy. Especially, stimuli-responsive nanomaterials stand out among others and have been widely researched because of their unique spatiotemporal control advantages. Therefore, it's necessary to summarize the application of those stimuli-responsive nanomaterials in ferroptosis. Here, we describe the physiological feature of ferroptosis and illustrate the current challenges to induce ferroptosis for cancer therapy. Then, nanomaterials that induce ferroptosis are classified and elaborated according to the external and internal stimuli. Finally, the future perspectives in the field are proposed. We hope this review facilitates paving the way for the design of intelligent nano-ferroptosis inducers.

Curcumin Induces Ferroptosis in Follicular Thyroid Cancer by Upregulating HO-1 Expression

Follicular thyroid cancer (FTC) is a highly aggressive type of endocrine malignancy. It is necessary to investigate the mechanisms of tumorigenesis and therapeutic pathways in patients with FTC. Haem oxygenase-1 (HO-1) can regulate oxidative stress and the occurrence of tumors and diseases. In this study, we discovered that HO-1 was abnormally overexpressed in FTC compared with adjacent tissues. However, the HO-1 overexpression was demonstrated to decrease cell viability and to potentially activate the ferroptosis signalling pathway. Ferroptosis is a newly identified form of oxidative cell death and is currently being targeted as a new cancer treatment. Tumorigenesis is significantly inhibited by curcumin. The present study shows that curcumin inhibits the growth of FTC by increasing the HO-1 expression, further activating the ferroptosis pathway. This study demonstrates that the HO-1-ferroptosis signalling pathway might play an important role in FTC tumorigenesis, and that curcumin inhibits the growth of FTC cells by affecting this pathway.

Increased expression of GPX4 promotes the tumorigenesis of thyroid cancer by inhibiting ferroptosis and predicts poor clinical outcomes

BACKGROUND

Ferroptosis plays a critical role in suppressing cancer progression, and its essential regulator is glutathione peroxidase 4 (GPX4). High GPX4 expression can inhibit accumulation of iron, thus suppressing ferroptosis. However, its function in thyroid cancer has not been fully illuminated. Here, we explore the effect of GPX4 on thyroid cancer tumorigenesis and prognosis.

METHODS

Based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, GPX4 expression was investigated in cancer tissues and adjacent tissues. We determined the biological functions of GPX4-associated differentially expressed genes (DEGs) by using the "clusterProfiler" R package. In addition, the predictive value of GPX4 in thyroid cancer was assessed by using Cox regression analysis and nomograms. Finally, we conducted several in vitro experiments to determine the influence of GPX4 expression on proliferation and ferroptosis in thyroid cancer cells.

RESULTS

GPX4 expression was obviously elevated in thyroid cancer tissues compared with normal tissues. Biological function analysis indicated enrichment in muscle contraction, contractile fiber, metal ion transmembrane transporter activity, and complement and coagulation cascades. GPX4 overexpression was associated with stage T3-T4 and pathologic stage III-IV in thyroid cancer patients. Cox regression analysis indicated that GPX4 may be a risk factor for the overall survival of thyroid cancer patients. In vitro research showed that knockdown of GPX4 suppressed proliferation and induced ferroptosis in thyroid cancer cells.

CONCLUSIONS

GPX4 overexpression in thyroid cancer might play an essential role in tumorigenesis and may have prognostic value for thyroid cancer patients.

Understanding the mechanistic roles of environmental heavy metal stressors in regulating ferroptosis: adding new paradigms to the links with diseases

Ferroptosis is a new type of iron-dependent cell death induced by a failure of the lipid repair protein GPX4 or the Xc- antiporter, which is essential for glutathione production. Some heavy metals such as arsenic (As), cobalt (Co), cadmium (Cd), iron (Fe), magnesium (Mg), manganese (Mn), nickel (Ni), mercury (Hg) as well as zinc (Zn) are shown to induce ferroptotic cell death involving the generation of oxidative stress, mitochondrial dysfunctioning, lipid peroxidation, and several other cellular etiologies. However, selenium (Se) treatment has been shown to enhance adaptive transcription responses to protect cells from ferroptosis. Heavy metals like Cadmium exposure activated ALK4/5 signaling via Smad3 and Akt signaling which leads to cell death mechanism. Continuous exposure to a small dose of mercury can damage tissues, and methylmercury bind to sulfhydryl proteins and GSH, this elevates oxidative stress, free radical accumulation, glutathione depletion, mitochondrial damage, and inhibited the nuclear factor-κB pathway which leads to ferroptotic cell death. Animals exposed to nickel and cobalt may have increased lipid peroxidation which can induce ferroptosis. Glutathione depletion is caused by Zn intoxication and exposure to manganese. These metals are systemic toxins that have been shown adverse effects on humans. Ferroptosis has recently been related to several pathological disorders, including, Alzheimer's disease, Parkinson's disease, Huntington's disease, as well as cardiovascular disease, and any type of cancer. For these disorders and some heavy metal toxicity, ferroptosis suppression needs to be looked upon as a promising therapeutic choice.

Multi-target tyrosine kinase inhibitor nanoparticle delivery systems for cancer therapy

Multi-target Tyrosine Kinase Inhibitors (MTKIs) have drawn substantial attention in tumor therapy. MTKIs could inhibit tumor cell proliferation and induce apoptosis by blocking the activity of tyrosine kinase. However, the toxicity and drug resistance of MTKIs severely restrict their further clinical application. The nano pharmaceutical technology based on MTKIs has attracted ever-increasing attention in recent years. Researchers deliver MTKIs through various types of nanocarriers to overcome drug resistance and improve considerably therapeutic efficiency. This review intends to summarize comprehensive applications of MTKIs nanoparticles in malignant tumor treatment. Firstly, the mechanism and toxicity were introduced. Secondly, various nanocarriers for MTKIs delivery were outlined. Thirdly, the combination treatment schemes and drug resistance reversal strategies were emphasized to improve the outcomes of cancer therapy. Finally, conclusions and perspectives were summarized to guide future research.

New perspectives on ferroptosis and its role in hepatocellular carcinoma

ABSTRACT

For a long time, the morbidity and mortality rates of hepatocellular carcinoma (HCC) have remained high. Since the concept of ferroptosis was introduced in 2012, researchers' perspectives have shifted toward finding novel ferroptosis-related treatment strategies, especially for tumors that are resistant to apoptosis. In recent years, there have been an increasing number of studies on ferroptosis, and these studies have found that ferroptosis has great potential and promise for cancer treatment. Ferroptosis is a kind of regulated cell death (RCD); unlike apoptosis, ferroptosis is an iron-dependent type of RCD driven by lipid peroxidation. The whole process of ferroptosis mainly revolves around three pathways (system xc-/ glutathione peroxidase 4 [GPX4]), lipid peroxidation, and iron metabolism), which are also regulated by various metabolic factors. This review will attempt to analyze the relationship between the system xc-/GPX4 pathway, lipid peroxidation, iron metabolism, and ferroptosis from three aspects (triggering, execution, and regulation), and the regulatory factors for ferroptosis will be summarized. In this review, we will also illustrate the relationship between ferroptosis and tumors as well as its application in tumors from the perspective of HCC. Finally, we will summarize the current limitations and needs and provide perspectives related to the focus of development in the future.

Corosolic acid sensitizes ferroptosis by upregulating HERPUD1 in liver cancer cells

Primary liver cancer is the third leading cause of cancer death in the world, and the lack of effective treatments is the main reason for the high mortality. Corosolic acid (CA) has been proved to have antitumor activity. In this study, we found that CA can sensitize liver cancer cells to ferroptosis, which is a regulated form of cell death characterized by iron-dependent lipid peroxides reaching lethal levels. Here, we revealed that CA can inhibit glutathione (GSH) synthesis via HERPUD1, decreasing the cellular GSH level and causing liver cancer cells to become more sensitive to ferroptosis. Mechanistically, further studies found that HERPUD1 reduced the ubiquitination of the GSS-associated E3 ubiquitin ligase MDM2, which promoted ubiquitination of GSS, thereby inhibiting GSH synthesis to increase ferroptosis susceptibility. Importantly, a mouse xenograft model also demonstrated that CA inhibits tumor growth via HERPUD1. Collectively, our findings suggesting that CA is a candidate component for the development of treatments against liver cancer.

System Xc−/GSH/GPX4 axis: An important antioxidant system for the ferroptosis in drug-resistant solid tumor therapy

The activation of ferroptosis is a new effective way to treat drug-resistant solid tumors. Ferroptosis is an iron-mediated form of cell death caused by the accumulation of lipid peroxides. The intracellular imbalance between oxidant and antioxidant due to the abnormal expression of multiple redox active enzymes will promote the produce of reactive oxygen species (ROS). So far, a few pathways and regulators have been discovered to regulate ferroptosis. In particular, the cystine/glutamate antiporter (System Xc−), glutathione peroxidase 4 (GPX4) and glutathione (GSH) (System Xc−/GSH/GPX4 axis) plays a key role in preventing lipid peroxidation-mediated ferroptosis, because of which could be inhibited by blocking System Xc−/GSH/GPX4 axis. This review aims to present the current understanding of the mechanism of ferroptosis based on the System Xc−/GSH/GPX4 axis in the treatment of drug-resistant solid tumors.

Perspectives and mechanisms for targeting ferroptosis in the treatment of hepatocellular carcinoma

Ferroptosis is a novel process of regulated cell death discovered in recent years, mainly caused by intracellular lipid peroxidation. It is morphologically manifested as shrinking of mitochondria, swelling of cytoplasm and organelles, rupture of plasma membrane, and formation of double-membrane vesicles. Work done in the past 5 years indicates that induction of ferroptosis is a promising strategy in the treatment of hepatocellular carcinoma (HCC). System xc^-/GSH/GPX4, iron metabolism, p53 and lipid peroxidation pathways are the main focus areas in ferroptosis research. In this paper, we analyze the ferroptosis-inducing drugs and experimental agents that have been used in the last 5 years in the treatment of HCC. We summarize four different key molecular mechanisms that induce ferroptosis, i.e., system xc^-/GSH/GPX4, iron metabolism, p53 and lipid peroxidation. Finally, we outline the prognostic analysis associated with ferroptosis in HCC. The findings summarized suggest that ferroptosis induction can serve as a promising new therapeutic approach for HCC and can provide a basis for clinical diagnosis and prevention of this disease.