Loss of COPZ1 induces NCOA4 mediated autophagy and ferroptosis in glioblastoma cell lines

Boric acid Increases Susceptibility to Chemotherapy by Targeting the Ferritinophagy Signaling Pathway in TMZ Resistant Glioblastoma Cells

Glioblastoma (GBM) is a common and highly lethal form of brain cancer. Temozolomide (TMZ) is the primary chemotherapy used for GBM, but it has limited effectiveness, with about half of the patients developing resistance. Iron regulatory proteins (IRPs) modulate genes involved in iron metabolism, while the nuclear receptor coactivator 4 (NCOA4) controls iron metabolism through a process called ferritinophagy. In this study, we investigated whether boric acid increases chemosensitivity mediated by ferritinophagy via the NCOA4 and IRP2 signaling pathways in TMZ-resistant GBM cells. First, we generated TMZ-resistant GBM cells (A172-R and T98G-R cells). Next, we investigated the effects of boric acid on cell viability, proliferation, cell cycle, and cell morphology in these cells. Additionally, following boric acid treatment, we analyzed the expression and protein levels of various biochemical markers in these cells. Boric acid treatment in A172-R and T98G-R cells suppressed cell viability and proliferation, arrested these cells in the G1/G0 cell cycle, and induced morphological differences. Boric acid increased NCOA4, IRP2, iron, and malondialdehyde (MDA) levels in A172-R and T98G-R cells, while glutathione (GSH) and glutathione peroxidase 4 (GPx4) levels decreased. Moreover, boric acid treatment increased intracellular iron levels and lipid peroxidation by inducing NCOA4 and IRP2 expression levels in TMZ-resistant cells. According to our results, boric acid may regulate chemosensitivity in A172-R and T98G-R cells mediated by NCOA4 and IRP2. In conclusion, the manipulative effects of boric acid on the ferritinophagy pathway hold the potential to sensitize TMZ-resistant GBM cells to chemotherapy.

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

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

Ferritinophagy: A novel insight into the double-edged sword in ferritinophagy-ferroptosis axis and human diseases

Nuclear receptor coactive 4 (NCOA4), which functions as a selective cargo receptor, is a critical regulator of the particularly autophagic degradation of ferritin, a process known as ferritinophagy. Mechanistically, NCOA4-mediated ferritinophagy performs an increasingly vital role in the maintenance of intracellular iron homeostasis by promoting ferritin transport and iron release as needed. Ferritinophagy is not only involved in iron-dependent responses but also in the pathogenesis and progression of various human diseases, including metabolism-related, neurodegenerative, cardiovascular and infectious diseases. Therefore, ferritinophagy is of great importance in maintaining cell viability and function and represents a potential therapeutic target. Recent studies indicated that ferritinophagy regulates the signalling pathway associated with ferroptosis, a newly discovered type of cell death characterised by iron-dependent lipid peroxidation. Although accumulating evidence clearly demonstrates the importance of the interplay between dysfunction in iron metabolism and ferroptosis, a deeper understanding of the double-edged sword effect of ferritinophagy in ferroptosis has remained elusive. Details of the mechanisms underlying the ferritinophagy-ferroptosis axis in regulating relevant human diseases remain to be elucidated. In this review, we discuss the latest research findings regarding the mechanisms that regulate the biological function of NCOA4-mediated ferritinophagy and its contribution to the pathophysiology of ferroptosis. The important role of the ferritinophagy-ferroptosis axis in human diseases will be discussed in detail, highlighting the great potential of targeting ferritinophagy in the treatment of diseases.

Arenobufagin regulates the p62-Keap1-Nrf2 pathway to induce autophagy-dependent ferroptosis in HepG2 cells

Hepatocellular carcinoma (HCC) is the most prevalent type of primary liver cancer, accounting for the overwhelming majority of malignant liver tumors. Therefore, how to effectively prevent and cure HCC has become a research hotspot. Many studies have shown that arenobufagin can induce apoptosis, ferroptosis, and autophagy of tumor cells. An increasing number of studies have shown that autophagy is closely linked to ferroptosis. In this study, HepG2 cells and BALB/c nude mice were used as research objects to explore the effect and preliminary mechanism of hepatoma cell autophagy and ferroptosis induced by arenobufagin. We found that arenobufagin can significantly inhibit tumor growth in vivo, and interestingly, we found that arenobufagin inhibited ferroptosis-related proteins Nrf2 and COX-2 in a dose-dependent manner and decreased the levels of reduced glutathione (GSH) and superoxide dismutase (T-SOD) in tissues, while increased the level of reduced malondialdehyde (MDA). In addition, we found that arenobufagin increased the levels of COX-2 and MDA in cells, decreased the levels of Nrf2, GSH, and T-SOD, increased the levels of tissue reactive oxygen species (ROS) and lipid ROS in a dose-dependent manner, and promoted ferroptosis in HepG2 cells. HepG2 cells were preprotected by autophagy inhibitor chloroquine (CQ) and ferroptosis inhibitor deferoxamine (DFO), and then treated with arenobufagin. It was found that CQ partially reversed the changes of COX-2 and Nrf2 expression and lipid peroxidation induced by arenobufagin-induced autophagy and HepG2 cells. Interestingly, CQ partially reversed the inhibition of arenobufagin on cytoplasmic junction protein (Keap1) and heme oxygenase-1 (HO-1) in p62-Keap1-Nrf2 pathway. At the same time, we found that the effect of arenobufagin on oxidative stress of HepG2 cells overexpressed by Nrf2 was significantly less than that of the control group. To sum up, arenobufagin promotes autophagy-dependent ferroptosis of HepG2 cells by inducing autophagy and regulating p62-Keap1-Nrf2 pathway. It is suggested that arenobufagin can be used as a potential intervention therapy.

Injectable hybrid hydrogels enable enhanced combination chemotherapy and roused anti-tumor immunity in the synergistic treatment of pancreatic ductal adenocarcinoma

Chemotherapy and immunotherapy have shown no significant outcome for unresectable pancreatic ductal adenocarcinoma (PDAC). Multi-drug combination therapy has become a consensus in clinical trials to explore how to arouse anti-tumor immunity and meanwhile overcome the poorly tumoricidal effect and the stroma barrier that greatly hinders drug penetration. To address this challenge, a comprehensive strategy is proposed to fully utilize both the ferroptotic vulnerability of PDAC to potently irritate anti-tumor immunity and the desmoplasia-associated focal adhesion kinase (FAK) to wholly improve the immunosuppressive microenvironment via sustained release of drugs in an injectable hydrogel for increasing drug penetration in tumor location and averting systematic toxicity. The injectable hydrogel ED-M@CS/MC is hybridized with micelles loaded with erastin that exclusively induces ferroptosis and a FAK inhibitor defactinib for inhibiting stroma formation, and achieves sustained release of the drugs for up to 12 days. With only a single intratumoral injection, the combination treatment with erastin and defactinib produces further anti-tumor performance both in xenograft and KrasG12D-engineered primary PDAC mice and synergistically promotes the infiltration of CD8+ cytotoxic T cells and the reduction of type II macrophages. The findings may provide a novel promising strategy for the clinical treatment of PDAC.

Melatonin improves stroke by inhibiting autophagy-dependent ferroptosis mediated by NCOA4 binding to FTH1

Ischemic stroke is a disease associated with high morbidity and disability rates; however, its pathogenesis remains elusive, and treatment options are limited. Ferroptosis, an iron-dependent form of cell death, represents a novel avenue for investigation. The objective of this study was to explore the role of melatonin in MCAO-induced ferroptosis and elucidate its underlying molecular mechanism. To simulate brain damage and neuronal injury caused by ischemic stroke, we established a mouse model of MCAO and an HT-22 cell model of OGD/R. The therapeutic efficacy of melatonin was assessed through measurements of infarct size, brain edema, and neurological scores. Additionally, qRT-PCR, WB analysis, and Co-IP assays were employed to investigate the impact of melatonin on ferroptosis markers such as NCOA4 and FTH1 expression levels. Confocal microscopy was utilized to confirm the colocalization between ferritin and lysosomes. Furthermore, we constructed a SIRT6 siRNA model to validate the regulatory effect exerted by SIRT6 on NCOA4 as well as their binding interaction. The present study provides initial evidence that melatonin possesses the ability to mitigate neuronal damage induced by MCAO and OGD/R. Assessment of markers for oxidative damage and ferroptosis revealed that melatonin effectively inhibits intracellular Fe2+ levels, thereby suppressing ferroptosis. Additionally, our findings demonstrate that melatonin modulates the interaction between FTH1 and NCOA4 via SIRT6, influencing ferritin autophagy without affecting cellular macroautophagy. These findings provide reliable data support for the promotion and application of melatonin in clinical practice.

International consensus guidelines for the definition, detection, and interpretation of autophagy-dependent ferroptosis

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results.Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy.

Chemoproteomics enables identification of coatomer subunit zeta-1 targeted by a small molecule for enterovirus A71 inhibition

Human enterovirus A71 (EV-A71) is a significant etiological agent responsible for epidemics of hand, foot, and mouth disease (HFMD) in Asia-Pacific regions. There are presently no licensed antivirals against EV-A71, and the druggable target for EV-A71 remains very limited. The phenotypic hit 10,10'-bis(trifluoromethyl) marinopyrrole A derivative, herein termed MPA-CF3, is a novel potent small-molecule inhibitor against EV-A71, but its pharmacological target(s) and antiviral mechanisms are not defined. Here, quantitative chemoproteomics deciphered the antiviral target of MAP-CF3 as host factor coatomer subunit zeta-1 (COPZ1). Mechanistically, MPA-CF3 disrupts the interaction of COPZ1 with the EV-A71 nonstructural protein 2C by destabilizing COPZ1 upon binding. The destruction of this interaction blocks the coatomer-mediated transport of 2C to endoplasmic reticulum, and ultimately inhibits EV-A71 replication. Taken together, our study disclosed that MPA-CF3 can be a structurally novel host-targeting anti-EV-A71 agent, providing a structural basis for developing the COPZ1-targeting broad-spectrum antivirals against enteroviruses. The mechanistic elucidation of MPA-CF3 against EV-A71 may offer an alternative COPZ1-involved therapeutic pathway for enterovirus infection.

Ferroptosis in glioma therapy: advancements in sensitizing strategies and the complex tumor-promoting roles

Ferroptosis, an iron-dependent form of non-apoptotic regulated cell death, is induced by the accumulation of lipid peroxides on cellular membranes. Over the past decade, ferroptosis has emerged as a crucial process implicated in various physiological and pathological systems. Positioned as an alternative modality of cell death, ferroptosis holds promise for eliminating cancer cells that have developed resistance to apoptosis induced by conventional therapeutics. This has led to a growing interest in leveraging ferroptosis for cancer therapy across diverse malignancies. Gliomas are tumors arising from glial or precursor cells, with glioblastoma (GBM) being the most common malignant primary brain tumor that is associated with a dismal prognosis. This review provides a summary of recent advancements in the exploration of ferroptosis-sensitizing methods, with a specific focus on their potential application in enhancing the treatment of gliomas. In addition to summarizing the therapeutic potential, this review also discusses the intricate interplay of ferroptosis and its potential tumor-promoting roles within gliomas. Recognizing these dual roles is essential, as they could potentially complicate the therapeutic benefits of ferroptosis. Exploring strategies aimed at circumventing these tumor-promoting roles could enhance the overall therapeutic efficacy of ferroptosis in the context of glioma treatment.

Adaptations of membrane trafficking in cancer and tumorigenesis

Membrane trafficking, a fundamental cellular process encompassing the transport of molecules to specific organelles, endocytosis at the plasma membrane and protein secretion, is crucial for cellular homeostasis and signalling. Cancer cells adapt membrane trafficking to enhance their survival and metabolism, and understanding these adaptations is vital for improving patient responses to therapy and identifying therapeutic targets. In this Review, we provide a concise overview of major membrane trafficking pathways and detail adaptations in these pathways, including COPII-dependent endoplasmic reticulum (ER)-to-Golgi vesicle trafficking, COPI-dependent retrograde Golgi-to-ER trafficking and endocytosis, that have been found in cancer. We explore how these adaptations confer growth advantages or resistance to cell death and conclude by discussing the potential for utilising this knowledge in developing new treatment strategies and overcoming drug resistance for cancer patients.

Cryptochrome 1 regulates ovarian granulosa cell senescence through NCOA4-mediated ferritinophagy

Age-associated decreases in follicle number and oocyte quality result in a decline in female fertility, which is associated with increased infertility. Granulosa cells play a major role in oocyte development and maturation both in vivo and in vitro. However, it is unclear whether a reduction in cryptochrome 1 (Cry1) expression contributes to granulosa cell senescence, and further exploration is needed to understand the underlying mechanisms. In this study, we investigated the role of Cry1, a core component of the molecular circadian clock, in the regulation of senescence in ovarian granulosa cells. Western blotting and qRT-PCR showed that Cry1 expression was downregulated in aged human ovarian granulosa cells and was correlated with age and anti-Müllerian hormone (AMH) levels. RNA-seq analysis suggested that ferritinophagy was increased after Cry1 knockdown in KGN cells. MDA, iron, and reactive oxygen species (ROS) assays were used to detect cellular ferritinophagy levels. Ferroptosis inhibitors, iron chelators, autophagy inhibitors, and nuclear receptor coactivator 4 (NCOA4) knockdown alleviated KGN cell senescence induced by Cry1 knockdown. Immunofluorescence, immunoprecipitation, and ubiquitination assays indicated that Cry1 affected NCOA4 ubiquitination and degradation through HERC2, thereby affecting NCOA4-mediated ferritinophagy and causing granulosa cell senescence. KL201, a Cry1 stabilizer, enhanced ovarian function in naturally aged mice by reducing ferritinophagy. Our study reveals the potential mechanisms of action of Cry1 during ovarian aging and provides new insights for the clinical treatment of age-related fertility decline.

Ferroptosis is an effective strategy for cancer therapy

Ferroptosis is a form of intracellular iron-dependent cell death that differs from necrosis, autophagy and apoptosis. Intracellular iron mediates Fenton reaction resulting in lipid peroxidation production, which in turn promotes cell death. Although cancer cell exhibit's ability to escape ferroptosis by multiple pathways such as SLC7A11, GPX4, induction of ferroptosis could inhibit cancer cell proliferation, migration and invasion. In tumor microenvironment, ferroptosis could affect immune cell (T cells, macrophages etc.) activity, which in turn regulates tumor immune escape. In addition, ferroptosis in cancer cells could activate immune cell activity by antigen processing and presentation. Therefore, ferroptosis could be an effective strategy for cancer therapy such as chemotherapy, radiotherapy, and immunotherapy. In this paper, we reviewed the role of ferroptosis on tumor progression and therapy, which may provide a strategy for cancer treatment.

Hypoxia causes trophoblast cell ferroptosis to induce miscarriage through lnc-HZ06/HIF1α-SUMO/NCOA4 axis

Defects of human trophoblast cells may induce miscarriage (abnormal early embryo loss), which is generally regulated by lncRNAs. Ferroptosis is a newly identified iron-dependent programmed cell death. Hypoxia is an important and unavoidable feature in mammalian cells. However, whether hypoxia might induce trophoblast cell ferroptosis and then induce miscarriage, as well as regulated by a lncRNA, was completely unknown. In this work, we discovered at the first time that hypoxia could result in ferroptosis of human trophoblast cells and then induce miscarriage. We also identified a novel lncRNA (lnc-HZ06) that simultaneously regulated hypoxia (indicated by HIF1α protein), ferroptosis, and miscarriage. In mechanism, HIF1α-SUMO, instead of HIF1α itself, primarily acted as a transcription factor to promote the transcription of NCOA4 (ferroptosis indicator) in hypoxic trophoblast cells. Lnc-HZ06 promoted the SUMOylation of HIF1α by suppressing SENP1-mediated deSUMOylation. HIF1α-SUMO also acted as a transcription factor to promote lnc-HZ06 transcription. Thus, both lnc-HZ06 and HIF1α-SUMO formed a positive auto-regulatory feedback loop. This loop was up-regulated in hypoxic trophoblast cells, in RM villous tissues, and in placental tissues of hypoxia-treated mice, which further induced ferroptosis and miscarriage by up-regulating HIF1α-SUMO-mediated NCOA4 transcription. Furthermore, knockdown of either murine lnc-hz06 or Ncoa4 could efficiently suppress ferroptosis and alleviate miscarriage in hypoxic mouse model. Taken together, this study provided new insights in understanding the regulatory roles of lnc-HZ06/HIF1α-SUMO/NCOA4 axis among hypoxia, ferroptosis, and miscarriage, and also offered an effective approach for treatment against miscarriage.

Identification of a ferritinophagy inducer via sinomenine modification for the treatment of colorectal cancer

Ferritinophagy is a cellular process to release redox-active iron. Excessive activation of ferritinophagy ultimately results in ferroptosis characterized by ROS accumulation which plays important roles in the development and progression of cancer. Sinomenine, a main bioactive alkaloid from the traditional Chinese medicine Sinomenum acutum, inhibits the proliferation of cancer cells by promoting ROS production. Herein, new compounds were designed and synthesized through the stepwise optimization of sinomenine. Among them, D3-3 induced the production of lipid ROS, and significantly promoted colorectal cancer cells to release the ferrous ion in an autophagy-dependent manner. Moreover, D3-3 enhanced the interaction of FTH1-NCOA4, indicating the activation of ferritinophagy. In vivo experiments showed that D3-3 restrained tumor growth and promoted lipid peroxidation in the HCT-116 xenograft model. These findings demonstrated that D3-3 is an inducer of ferritinophagy, eventually triggering ferroptosis. Compound D3-3, as the first molecule to be definitively demonstrated to induce ferritinophagy, is worth further evaluation as a promising drug candidate in the treatment of colorectal cancer.

SMG9 is a novel prognostic-related biomarker in glioma correlating with ferroptosis and immune infiltrates

Background

Glioma is the most frequent type of malignancy that may damage the brain with high morbidity and mortality rates and patients' prognoses are still dismal. Ferroptosis, a newly uncovered mode of programmed cell death, may be triggered to destroy glioma cells. Nevertheless, the significance of ferroptosis-related genes (FRGs) in predicting prognosis in glioma individuals is still a mystery.

Methods

The CGGA (The Chinese Glioma Atlas), GEO (Gene Expression Omnibus), and TCGA (The Cancer Genome Atlas) databases were all searched to obtain the glioma expression dataset. First, TCGA was searched to identify differentially expressed genes (DEGs). This was followed by a machine learning algorithm-based screening of the glioma's most relevant genes. Additionally, these genes were subjected to Gene Ontology (GO) and KEGG (Kyoto Encyclopedia of Genes and Genomes) functional enrichment analyses. The chosen biological markers were then submitted to single-cell, immune function, and gene set enrichment analysis (GSEA). In addition, we performed functional enrichment and Mfuzz expression profile clustering on the most promising biological markers to delve deeper into their regulatory mechanisms and assess their clinical diagnostic capacities.

Results

We identified 4444 DEGs via differential analysis and 564 FRGs from the FerrDb database. The two were subjected to intersection analysis, which led to the discovery of 143 overlapping genes. After that, glioma biological markers were identified in fourteen genes by the use of machine learning methods. In terms of its use for clinical diagnosis, SMG9 stands out as the most significant among these biomarkers.

Conclusion

In light of these findings, the identification of SMG9 as a new biological marker has the potential to provide information on the mechanism of action and the effect of the immune milieu in glioma. The promise of SMG9 in glioma prognosis prediction warrants more study.

Targeting SIRT3 sensitizes glioblastoma to ferroptosis by promoting mitophagy and inhibiting SLC7A11

Glioblastoma (GBM) cells require large amounts of iron for tumor growth and progression, which makes these cells vulnerable to destruction via ferroptosis induction. Mitochondria are critical for iron metabolism and ferroptosis. Sirtuin-3 (SIRT3) is a deacetylase found in mitochondria that regulates mitochondrial quality and function. This study aimed to characterize SIRT3 expression and activity in GBM and investigate the potential therapeutic effects of targeting SIRT3 while also inducing ferroptosis in these cells. We first found that SIRT3 expression was higher in GBM tissues than in normal brain tissues and that SIRT3 protein expression was upregulated during RAS-selective lethal 3 (RSL3)-induced GBM cell ferroptosis. We then observed that inhibition of SIRT3 expression and activity in GBM cells sensitized GBM cells to RSL3-induced ferroptosis both in vitro and in vivo. Mechanistically, SIRT3 inhibition led to ferrous iron and ROS accumulation in the mitochondria, which triggered mitophagy. RNA-Sequencing analysis revealed that upon SIRT3 knockdown in GBM cells, the mitophagy pathway was upregulated and SLC7A11, a critical antagonist of ferroptosis via cellular import of cystine for glutathione (GSH) synthesis, was downregulated. Forced expression of SLC7A11 in GBM cells with SIRT3 knockdown restored cellular cystine uptake and consequently the cellular GSH level, thereby partially rescuing cell viability upon RSL3 treatment. Furthermore, in GBM cells, SIRT3 regulated SLC7A11 transcription through ATF4. Overall, our study results elucidated novel mechanisms underlying the ability of SIRT3 to protect GBM from ferroptosis and provided insight into a potential combinatorial approach of targeting SIRT3 and inducing ferroptosis for GBM treatment.

Ferroptosis as a Therapeutic Target in Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a cerebrovascular disorder with significant mortality and morbidity. Neural injury in SAH is mediated through a variety of pathophysiological processes. Currently available treatments are either nonspecific in targeting the basic pathophysiological mechanisms that result in neural damage in SAH, or merely focus on vasospasm. Ferroptosis is a type of programmed iron dependent cell death, which has received attention due to its possible role in neural injury in SAH. Herein, we review how intracellular iron overload mediates the production of reactive free radicals and lipid peroxidation through a variety of biochemical pathways in SAH. This in turn results in induction of ferroptosis, as well as exacerbation of vasospasm. We also discuss several therapeutic agents that have been shown to inhibit ferroptosis through targeting different steps of the process. Such agents have proven effective in ameliorating vasospasm, neural damage, and neurobehavioral outcomes in animal models of SAH. Human studies to test the safety and efficacy of intrathecal or parenteral administration of the inhibitors of ferroptosis in improving outcomes of SAH patients are warranted. There are currently a few ongoing clinical trials pursuing this therapeutic concept, the results of which will be critical to determine the value of ferroptosis as a novel therapeutic target in SAH.

Targeting PKD2 aggravates ferritinophagy-mediated ferroptosis via promoting autophagosome-lysosome fusion and enhances efficacy of carboplatin in lung adenocarcinoma

Ferroptosis is an iron-dependent cell death and affects efficacies of multiple antitumor regimens, showing a great potential in cancer therapy. Protein kinase D2 (PKD2) plays a crucial role in regulating necrosis and apoptosis. However, the relationship of PKD2 and ferroptosis is still elusive. In this study, we mainly analyzed the roles of PKD2 on ferroptosis and chemotherapy in lung adenocarcinoma (LUAD). We found PKD2 was highly expressed in LUAD and silencing PKD2 could promote erastin-induced reactive oxygen species (ROS), malondialdehyde (MDA) accumulation, intracellular iron content and LUAD cells death. Mechanistically, augmenting PKD2 could prevent autophagic degradation of ferritin, which could be impaired by bafilomycin A1. We further found that PKD2 overexpression would promote LC3B-II, p62/SQSTM1 accumulation and block autophagosome-lysosome fusion in a TFEB-independent manner, which could be impaired by bafilomycin A1. Bafilomycin A1 stimulation could weaken ferroptosis promotion by PKD2 abrogation. Silencing ferritin heavy chain-1 (FTH1) could reverse the resistance to ferroptosis by PKD2 overexpression. Additionally, in vitro and vivo experiments validated PKD2 promoted proliferation, migration and invasion of LUAD cells. PKD2 knockdown or pharmacological inhibition by CRT0066101 could enhance efficacy of carboplatin in LUAD via ferroptosis and apoptosis. Collectively, our study revealed that abrogation of PKD2 could aggravate ferritinophagy-mediated ferroptosis by promoting autophagosome-lysosome fusion and enhance efficacy of carboplatin in LUAD. Targeting PKD2 to induce ferroptosis may be a promising strategy for LUAD therapy.

Selenoprotein P expression in glioblastoma as a regulator of ferroptosis sensitivity: preservation of GPX4 via the cycling-selenium storage

Glioblastoma (GBM) is one of the most aggressive and deadly brain tumors; however, its current therapeutic strategies are limited. Selenoprotein P (SeP; SELENOP, encoded by the SELENOP gene) is a unique selenium-containing protein that exhibits high expression levels in astroglia. SeP is thought to be associated with ferroptosis sensitivity through the induction of glutathione peroxidase 4 (GPX4) via selenium supplementation. In this study, to elucidate the role of SeP in GBM, we analyzed its expression in GBM patients and found that SeP expression levels were significantly higher when compared to healthy subjects. Knock down of SeP in cultured GBM cells resulted in a decrease in GPX1 and GPX4 protein levels. Under the same conditions, cell death caused by RSL3, a ferroptosis inducer, was enhanced, however this enhancement was canceled by supplementation of selenite. These results indicate that SeP expression contributes to preserving GPX and selenium levels in an autocrine/paracrine manner, i.e., SeP regulates a dynamic cycling-selenium storage system in GBM. We also confirmed the role of SeP expression in ferroptosis sensitivity using patient-derived primary GBM cells. These findings indicate that expression of SeP in GBM can be a significant therapeutic target to overcome anticancer drug resistance.

Homeostatic iron regulatory protein drives glioblastoma growth via tumor cell-intrinsic and sex-specific responses

Background

Glioblastoma (GBM) displays alterations in iron that drive proliferation and tumor growth. Iron regulation is complex and involves many regulatory mechanisms, including the homeostatic iron regulator (HFE) gene, which encodes the homeostatic iron regulatory protein. While HFE is upregulated in GBM and correlates with poor survival outcomes, the function of HFE in GBM remains unclear.

Methods

We interrogated the impact of cell-intrinsic Hfe expression on proliferation and survival of intracranially implanted animals through genetic gain- and loss-of-function approaches in syngeneic mouse glioma models, along with in vivo immune assessments. We also determined the expression of iron-associated genes and their relationship to survival in GBM using public data sets and used transcriptional profiling to identify differentially expressed pathways in control compared to Hfe-knockdown cells.

Results

Overexpression of Hfe accelerated GBM proliferation and reduced animal survival, whereas suppression of Hfe induced apoptotic cell death and extended survival, which was more pronounced in females and associated with attenuation of natural killer cells and CD8+ T cell activity. Analysis of iron gene signatures in Hfe-knockdown cells revealed alterations in the expression of several iron-associated genes, suggesting global disruption of intracellular iron homeostasis. Further analysis of differentially expressed pathways revealed oxidative stress as the top pathway upregulated following Hfe loss. Hfe knockdown indeed resulted in enhanced 55Fe uptake and generation of reactive oxygen species.

Conclusions

These findings reveal an essential function for HFE in GBM cell growth and survival, as well as a sex-specific interaction with the immune response.

Autophagy machinery in glioblastoma: The prospect of cell death crosstalk and drug resistance with bioinformatics analysis

Brain tumors are common malignancies with high mortality and morbidity in which glioblastoma (GB) is a grade IV astrocytoma with heterogeneous nature. The conventional therapeutics for the GB mainly include surgery and chemotherapy, however their efficacy has been compromised due to the aggressiveness of tumor cells. The dysregulation of cell death mechanisms, especially autophagy has been reported as a factor causing difficulties in cancer therapy. As a mechanism contributing to cell homeostasis, the autophagy process is hijacked by tumor cells for the purpose of aggravating cancer progression and drug resistance. The autophagy function is context-dependent and its role can be lethal or protective in cancer. The aim of the current paper is to highlight the role of autophagy in the regulation of GB progression. The cytotoxic function of autophagy can promote apoptosis and ferroptosis in GB cells and vice versa. Autophagy dysregulation can cause drug resistance and radioresistance in GB. Moreover, stemness can be regulated by autophagy and overall growth as well as metastasis are affected by autophagy. The various interventions including administration of synthetic/natural products and nanoplatforms can target autophagy. Therefore, autophagy can act as a promising target in GB therapy.

Research progress on ferroptosis in gliomas (Review)

Glioma is the most prevalent type of brain tumor characterized by a poor 5-year survival rate and a high mortality rate. Malignant gliomas are commonly treated by surgery, chemotherapy and radiotherapy. However, due to toxicity and resistance to chemoradiotherapy, these treatments can be ineffective. Anxiety and depression are highly prevalent in patients with glioma, adversely affecting disease prognosis and posing societal concerns. Ferroptosis is a type of non-apoptotic, iron-dependent cell death characterized by the accumulation of lethal reactive oxygen species produced by iron metabolism, and it serves a key role in numerous diseases. Regulation of iron phagocytosis may serve as a therapeutic strategy for the development of novel glioma treatments. The present review discusses the mechanisms underlying the occurrence and regulation of ferroptosis, its role in the genesis and evolution of gliomas, and its association with glioma-related anxiety and depression. By exploring potential targets for glioma treatment, the present review provides a theoretical basis for the development of novel therapeutic strategies against glioma.

COPI Vesicle Disruption Inhibits Mineralization via mTORC1-Mediated Autophagy

Bone mineralization is a sophisticated regulated process composed of crystalline calcium phosphate and collagen fibril. Autophagy, an evolutionarily conserved degradation system, whereby double-membrane vesicles deliver intracellular macromolecules and organelles to lysosomes for degradation, has recently been shown to play an essential role in mineralization. However, the formation of autophagosomes in mineralization remains to be determined. Here, we show that Coat Protein Complex I (COPI), responsible for Golgi-to-ER transport, plays a pivotal role in autophagosome formation in mineralization. COPI vesicles were increased after osteoinduction, and COPI vesicle disruption impaired osteogenesis. Mechanistically, COPI regulates autophagy activity via the mTOR complex 1 (mTORC1) pathway, a key regulator of autophagy. Inhibition of mTOR1 rescues the impaired osteogenesis by activating autophagy. Collectively, our study highlights the functional importance of COPI in mineralization and identifies COPI as a potential therapeutic target for treating bone-related diseases.

Ferritinophagy: research advance and clinical significance in cancers

Ferritinophagy, a process involving selective autophagy of ferritin facilitated by nuclear receptor coactivator 4 (NCOA4), entails the recognition of ferritin by NCOA4 and subsequent delivery to the autophagosome. Within the autophagosome, ferritin undergoes degradation, leading to the release of iron in the lysosome. It is worth noting that excessive iron levels can trigger cell death. Recent evidence has elucidated the significant roles played by ferritinophagy and ferroptosis in regulation the initiation and progression of cancer. Given the crucial role of ferritinophagy in tumor biology, it may serve as a potential target for future anti-tumor therapeutic interventions. In this study, we have provided the distinctive features of ferritinophagy and its distinctions from ferroptosis. Moreover, we have briefly examined the fundamental regulatory mechanisms of ferritinophagy, encompassing the involvement of the specific receptor NCOA4, the Nrf2/HO-1 signaling and other pathways. Subsequently, we have synthesized the current understanding of the impact of ferritinophagy on cancer progression and its potential therapeutic applications, with a particular emphasis on the utilization of chemotherapy, nanomaterials, and immunotherapy to target the ferritinophagy pathway for anti-tumor purposes.

Hypoxia Aggravates Neuron Ferroptosis in Early Brain Injury Following Subarachnoid Hemorrhage via NCOA4-Meditated Ferritinophagy

The occurrence of early brain injury (EBI) significantly contributes to the unfavorable prognosis observed in patients with subarachnoid hemorrhage (SAH). During the process of EBI, a substantial quantity of iron permeates into the subarachnoid space and brain tissue, thereby raising concerns regarding its metabolism. To investigate the role and metabolic processes of excessive iron in neurons, we established both in vivo and in vitro models of SAH. We substantiated that ferritinophagy participates in iron metabolism disorders and promotes neuronal ferroptosis using an in vivo model, as detected by key proteins such as ferritin heavy chain 1, glutathione peroxidase 4, autophagy related 5, nuclear receptor coactivator 4 (NCOA4), LC3B, and electron microscopy results. By interfering with NCOA4 expression in vitro and in vivo, we confirmed the pivotal role of elevated NCOA4 levels in ferritinophagy during EBI. Additionally, our in vitro experiments demonstrated that the addition of oxyhemoglobin alone did not result in a significant upregulation of NCOA4 expression. However, simultaneous addition of oxyhemoglobin and hypoxia exposure provoked a marked increase in NCOA4 expression and heightened ferritinophagy in HT22 cells. Using YC-1 to inhibit hypoxia signaling in in vitro and in vitro models effectively attenuated neuronal ferroptosis. Collectively, we found that the hypoxic microenvironment during the process of EBI exaggerates iron metabolism abnormalities, leading to poor prognoses in SAH. The findings also offer a novel and potentially effective foundation for the treatment of SAH, with the aim of alleviating hypoxia.

Ferroptosis: Emerging Role in Diseases and Potential Implication of Bioactive Compounds

Ferroptosis is a form of cell death that is distinguished from other types of death for its peculiar characteristics of death regulated by iron accumulation, increase in ROS, and lipid peroxidation. In the past few years, experimental evidence has correlated ferroptosis with various pathological processes including neurodegenerative and cardiovascular diseases. Ferroptosis also is involved in several types of cancer because it has been shown to induce tumor cell death. In particular, the pharmacological induction of ferroptosis, contributing to the inhibition of the proliferative process, provides new ideas for the pharmacological treatment of cancer. Emerging evidence suggests that certain mechanisms including the Xc- system, GPx4, and iron chelators play a key role in the regulation of ferroptosis and can be used to block the progression of many diseases. This review summarizes current knowledge on the mechanism of ferroptosis and the latest advances in its multiple regulatory pathways, underlining ferroptosis' involvement in the diseases. Finally, we focused on several types of ferroptosis inducers and inhibitors, evaluating their impact on the cell death principal targets to provide new perspectives in the treatment of the diseases and a potential pharmacological development of new clinical therapies.

A closer look at the role of iron in glioblastoma

Glioblastoma (GBM) is among the deadliest malignancies facing modern oncology. While our understanding of certain aspects of GBM biology has significantly increased over the last decade, other aspects, such as the role of bioactive metals in GBM progression, remain understudied. Iron is the most abundant transition metal found within the earth's crust and plays an intricate role in human physiology owing to its ability to participate in oxidation-reduction reactions. The importance of iron homeostasis in human physiology is apparent when examining the clinical consequences of iron deficiency or iron overload. Despite this, the role of iron in GBM progression has not been well described. Here, we review and synthesize the existing literature examining iron's role in GBM progression and patient outcomes, as well as provide a survey of iron's effects on the major cell types found within the GBM microenvironment at the molecular and cellular level. Iron represents an accessible target given the availability of already approved iron supplements and chelators. Improving our understanding of iron's role in GBM biology may pave the way for iron-modulating approaches to improve patient outcomes.

Overexpression of TMEM150A in glioblastoma multiforme patients correlated with dismal prognoses and compromised immune statuses

Transmembrane proteins have exhibited a significant correlation with glioblastoma multiforme (GBM). The current study elucidates the roles of transmembrane protein 150A (TMEM150A) in GBM. Data on patients with GBM were collected from The Cancer Genome Atlas and Xena databases. The objective was to identify the expression levels of TMEM150A in patients with GBM, and evaluate its diagnostic and prognostic values, accomplished using the receiver operating characteristic and survival analyses. On a cellular level, Cell Counting Kit-8, Wound healing, and Transwell experiments were performed to gauge the impact of TMEM150A on cell growth and migration. The study further investigated the correlation between TMEM150A expression and immune status, along with ribonucleic acid (RNA) modifications in GBM. The findings demonstrated TMEM150A overexpression in the cancerous tissues of patients with GBM, with an area under the curve value of 0.95. TMEM150A overexpression was significantly correlated with poor prognostic indicators. TMEM150A overexpression and isocitrate dehydrogenase (IDH) mutation status were predictive of poor survival time among patients with GBM. In vitro experiments indicated that suppressing TMEM150A expression could inhibit GBM cell proliferation, migration, and invasion. Moreover, TMEM150A overexpression was associated with stromal, immune, and estimate scores, immune cells (such as the T helper (Th) 17 cells, Th2 cells, and regulatory T cells), cell markers, and RNA modifications. Therefore, TMEM150A overexpression might serve as a promising biomarker for predicting poor prognosis in patients with GBM. Inhibiting TMEM150A expression holds the potential for improving the survival time of patients with GBM.

Hyperbaric oxygen improves cerebral ischemia-reperfusion injury in rats via inhibition of ferroptosis

BACKGROUND

Our previous study found that hyperbaric oxygen (HBO) attenuated cognitive impairment in mice induced by cerebral ischemia-reperfusion injury (CIRI). However, its mechanism of action is not fully understood. In this study, we aimed to establish a rat model of cerebral ischemia-reperfusion, explore the possible role of ferroptosis in the pathogenesis of CIRI, and observe the effect of HBO on ferroptosis-mediated CIRI.

METHODS

Sprague Dawley (SD) rats were randomly divided into control, model, Ferrostatin-1 (Fer-1), HBO and Fer-1+ HBO groups. Morris water maze, myelin basic protein (MBP) and β-tubulin immunoreactivity were assessed to evaluate the neuroprotective effects of HBO on cerebral ischemia reperfusion injury. Ferroptosis were examined to investigate the mechanism underlying the effects of HBO.

RESULTS

Our result showed that Fer-1 and HBO improved learning and memory ability in the navigation trail and probe trail of the Morris water maze and increased MBP and β-tubulin immunoreactivity of the cortex in the model rats. The levels of ferritin, malondialdehyde (MDA) and glutathione (GSH) in the serum were also reversed by Fer-1 and HBO treatment. Mitochondrial cristae dissolution and vacuolization were observed in the model group by transmission electron microscopy and these conditions were improved in the Fer-1 and HBO groups. Furthermore, Fer-1 and HBO treatment reversed Prostaglandin-Endoperoxide Synthase 2 (PTGS2), Iron Responsive Element Binding Protein 2 (IREB2), acyl-CoA synthetase long chain family member 4 (ACSL4) and Solute Carrier Family 7 Member 11 (SLC7A11) mRNA levels and Transferrin Receptor 1 (TFR1), ferritin light chain (FTL), ferritin heavy chain 1 (FTH1), glutathione peroxidase 4 (GPX4), Nuclear factor E2-related factor 2 (Nrf2), lysophosphatidylcholine acyltransferase 3 (LPCAT3), c-Jun N-terminal kinase (JNK), phosphorylated c-Jun N-terminal kinase (P-JNK) phosphorylated Extracellular signal-regulated protein kinase (P-ERK) and mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK) protein levels. The above changes were more pronounced in Fer-1+ HBOGroup.

DISCUSSION

The results of the present study indicated that HBO improves cerebral ischemia-reperfusion injury in rats, which may be related to inhibition of ferroptosis. This also means that ferroptosis may become a new target of HBO against CIRI.

The recent advancements of ferroptosis in the diagnosis, treatment and prognosis of ovarian cancer

Ovarian cancer affects the female reproductive system and is the primary cause of cancer related mortality globally. The imprecise and non-specific nature of ovarian cancer symptoms often results in patients being diagnosed at an advanced stage, with metastatic lesions extending beyond the ovary. This presents a significant clinical challenge and imposes a substantial economic burden on both patients and society. Despite advancements in surgery, chemotherapy, and immunotherapy, the prognosis for most patients with ovarian cancer remains unsatisfactory. Therefore, the development of novel treatment strategies is imperative. Ferroptosis, a distinct form of regulated cell death, characterized by iron-dependent lipid peroxidation, differs from autophagy, apoptosis, and necrosis, and may hold promise as a novel cell death. Numerous studies have demonstrated the involvement of ferroptosis in various conventional signaling pathways and biological processes. Recent investigations have revealed the significant contribution of ferroptosis in the initiation, progression, and metastasis of diverse malignant tumors, including ovarian cancer. Moreover, ferroptosis exhibits a synergistic effect with chemotherapy, radiotherapy, and immunotherapy in restraining the proliferation of ovarian cancer cells. The aforementioned implies that ferroptosis holds considerable importance in the management of ovarian cancer and has the potential to serve as a novel therapeutic target. The present review provides a comprehensive overview of the salient features of ferroptosis, encompassing its underlying mechanisms and functional role in ovarian cancer, along with the associated signaling pathways and genes. Furthermore, the review highlights the prospective utility of ferroptosis in the treatment of ovarian cancer.

Advances in the relationship between ferroptosis and epithelial-mesenchymal transition in cancer

Epithelial-mesenchymal transition (EMT) is a cellular reprogramming process that converts epithelial cells into mesenchymal-like cells with migratory and invasive capabilities. The initiation and regulation of EMT is closely linked to a range of transcription factors, cell adhesion molecules and signaling pathways, which play a key role in cancer metastasis and drug resistance. The regulation of ferroptosis is intricately linked to various cell death pathways, intracellular iron homeostasis, and the protein network governing iron supply and storage. The ability of ferroptosis to disrupt cancer cells and overcome drug resistance lies in its control of intracellular iron ion levels. EMT process can promote the accumulation of iron ions, providing conditions for ferroptosis. Conversely, ferroptosis may impact the regulatory network of EMT by modulating transcription factors, signaling pathways, and cell adhesion molecules. Thus, ferroptosis related genes and signaling pathways and oxidative homeostasis play important roles in the regulation of EMT. In this paper, we review the role of ferroptosis related genes and their signaling pathways in regulating cancer EMT to better understand the crosstalk mechanism between ferroptosis and EMT, aiming to provide better therapeutic strategies for eradicating cancer cells and overcoming drug resistance.

The induction of ferroptosis by KLF11/NCOA4 axis: the inhibitory role in clear cell renal cell carcinoma

Ferroptosis is a form of cell death and has great potential application in the treatment of many cancers, including clear cell renal cell carcinoma (ccRCC). Herein, we identified the essential roles of Krüppel-like factor 11 (KLF11) in suppressing the progression of ccRCC. By analyzing mRNA expression data from the Gene Expression Omnibus (GEO) database, we found that KLF11 was a significantly downregulated gene in ccRCC tissues. The results of subsequent functional assays verified that KLF11 played an antiproliferative role in ccRCC cells and xenograft tumors. Furthermore, gene set enrichment analysis indicated that ferroptosis was involved in ccRCC development, and correlation analysis revealed that KLF11 was positively related to ferroptosis drivers. We also found that KLF11 promoted ferroptosis in ccRCC by downregulating the protein expression of ferritin, system xc (-) cystine/glutamate antiporter (xCT), and glutathione peroxidase 4 (GPX4), acting as the inhibitory factors of ferroptosis and increasing the intracellular levels of lipid reactive oxygen species (ROS). As a transcriptional regulator, KLF11 significantly increased the promoter activity of nuclear receptor coactivator 4 (NCOA4), a gene significantly downregulated in ccRCC and whose low expression is associated with poor survival. The characteristics of ccRCC cells caused by KLF11 overexpression were reversed after NCOA4 silencing. In summary, the present study suggests that KLF11 suppresses the progression of ccRCC by increasing NCOA4 transcription. Therefore, the KLF11/NCOA4 axis may serve as a novel therapeutic target for human ccRCC.

Mechanisms and regulations of ferroptosis

Regulation of cell mortality for disease treatment has been the focus of research. Ferroptosis is an iron-dependent regulated cell death whose mechanism has been extensively studied since its discovery. A large number of studies have shown that regulation of ferroptosis brings new strategies for the treatment of various benign and malignant diseases. Iron excess and lipid peroxidation are its primary metabolic features. Therefore, genes involved in iron metabolism and lipid metabolism can regulate iron overload and lipid peroxidation through direct or indirect pathways, thereby regulating ferroptosis. In addition, glutathione (GSH) is the body's primary non-enzymatic antioxidants and plays a pivotal role in the struggle against lipid peroxidation. GSH functions as an auxiliary substance for glutathione peroxidase 4 (GPX4) to convert toxic lipid peroxides to their corresponding alcohols. Here, we reviewed the researches on the mechanism of ferroptosis in recent years, and comprehensively analyzed the mechanism and regulatory process of ferroptosis from iron metabolism and lipid metabolism, and then described in detail the metabolism of GPX4 and the main non-enzymatic antioxidant GSH in vivo.

The DRD2 Antagonist Haloperidol Mediates Autophagy-Induced Ferroptosis to Increase Temozolomide Sensitivity by Promoting Endoplasmic Reticulum Stress in Glioblastoma

PURPOSE

Temozolomide resistance remains a major obstacle in the treatment of glioblastoma (GBM). The combination of temozolomide with another agent could offer an improved treatment option if it could overcome chemoresistance and prevent side effects. Here, we determined the critical drug that cause ferroptosis in GBM cells and elucidated the possible mechanism by which drug combination overcomes chemoresistance.

EXPERIMENTAL DESIGN

Haloperidol/temozolomide synergism was assessed in GBM cell lines with different dopamine D2 receptor (DRD2) expression in vitro and in vivo. Inhibitors of ferroptosis, autophagy, endoplasmic reticulum (ER) stress and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) were used to validate the specific mechanisms by which haloperidol and temozolomide induce ferroptosis in GBM cells.

RESULTS

In the present work, we demonstrate that the DRD2 level is increased by temozolomide in a time-dependent manner and is inversely correlated with temozolomide sensitivity in GBM. The DRD2 antagonist haloperidol, a butylbenzene antipsychotic, markedly induces ferroptosis and effectively enhances temozolomide efficacy in vivo and in vitro. Mechanistically, haloperidol suppressed the effect of temozolomide on cAMP by antagonizing DRD2 receptor activity, and the increases in cAMP/PKA triggered ER stress, which led to autophagy and ferroptosis. Furthermore, elevated autophagy mediates downregulation of FTH1 expression at the posttranslational level in an autophagy-dependent manner and ultimately leads to ferroptosis.

CONCLUSIONS

Our results provide experimental evidence for repurposing haloperidol as an effective adjunct therapy to inhibit adaptive temozolomide resistance to enhance the efficacy of chemoradiotherapy in GBM, a strategy that may have broad prospects for clinical application.

Identification of hepatocellular carcinoma-related subtypes and development of a prognostic model: a study based on ferritinophagy-related genes

BACKGROUND

Hepatocellular carcinoma still has a high incidence and mortality rate worldwide, and further research is needed to investigate its occurrence and development mechanisms in depth in order to identify new therapeutic targets. Ferritinophagy is a type of autophagy and a key factor in ferroptosis that could influence tumor onset and progression. Although, the potential role of ferritinophagy-related genes (FRGs) in liver hepatocellular carcinoma (LIHC) is unknown.

METHODS

Single-cell RNA sequencing (scRNA-seq) data of LIHC were obtained from the Gene Expression Omnibus (GEO) dataset. In addition, transcriptome and clinical follow-up outcome data of individuals with LIHC were extracted from the The Cancer Genome Atlas (TCGA) dataset. FRGs were collected through the GeneCards database. Differential cell subpopulations were distinguished, and differentially expressed FRGs (DEFRGs) were obtained. Differential expression of FRGs and prognosis were observed according to the TCGA database. An FRG-related risk model was constructed to predict patient prognosis by absolute shrinkage and selection operator (LASSO) and COX regression analyses, and its prognosis predictive power was validated. Ultimately, the association between risk score and tumor microenvironment (TME), immune cell infiltration, immune checkpoints, drug sensitivity, and tumor mutation burden (TMB) was analyzed. We also used quantitative reverse transcription polymerase chain reaction (qRT-PCR) to validate the expression of key genes in normal liver cells and liver cancer cells.

RESULTS

We ultimately identified 8 cell types, and 7 differentially expressed FRGs genes (ZFP36, NCOA4, FTH1, FTL, TNF, PCBP1, CYB561A3) were found among immune cells, and we found that Monocytes and Macrophages were closely related to FRGs genes. Subsequently, COX regression analysis showed that patients with high expression of FTH1, FTL, and PCBP1 had significantly worse prognosis than those with low expression, and our survival prediction model, constructed based on age, stage, and risk score, showed better prognostic prediction ability. Our risk model based on 3 FRGs genes ultimately revealed significant differences between high-risk and low-risk groups in terms of immune infiltration and immune checkpoint correlation, drug sensitivity, and somatic mutation risk. Finally, we validated the key prognostic genes FTH1, FTL, using qRT-PCR, and found that the expression of FTH1 and FTL was significantly higher in various liver cancer cells than in normal liver cells. At the same time, immunohistochemistry showed that the expression of FTH1, FTL in tumor tissues was significantly higher than that in para-tumor tissues.

CONCLUSION

This study identifies a considerable impact of FRGs on immunity and prognosis in individuals with LIHC. The collective findings of this research provide new ideas for personalized treatment of LIHC and a more targeted therapy approach for individuals with LIHC to improve their prognosis.

Ferroptosis: a novel regulated cell death participating in cellular stress response, radiotherapy, and immunotherapy

BACKGROUND

Ferroptosis is a regulated cell death mode triggered by iron-dependent toxic membrane lipid peroxidation. As a novel cell death modality that is morphologically and mechanistically different from other forms of cell death, such as apoptosis and necrosis, ferroptosis has attracted extensive attention due to its association with various diseases. Evidence on ferroptosis as a potential therapeutic strategy has accumulated with the rapid growth of research on targeting ferroptosis for tumor suppression in recent years.

METHODS

We summarize the currently known characteristics and major regulatory mechanisms of ferroptosis and present the role of ferroptosis in cellular stress responses, including ER stress and autophagy. Furthermore, we elucidate the potential applications of ferroptosis in radiotherapy and immunotherapy, which will be beneficial in exploring new strategies for clinical tumor treatment.

RESULT AND CONCLUSION

Based on specific biomarkers and precise patient-specific assessment, targeting ferroptosis has great potential to be translated into practical new approaches for clinical cancer therapy, significantly contributing to the prevention, diagnosis, prognosis, and treatment of cancer.

A novel view of ferritin in cancer

Since its discovery more than 85 years ago, ferritin has principally been known as an iron storage protein. However, new roles, beyond iron storage, are being uncovered. Novel processes involving ferritin such as ferritinophagy and ferroptosis and as a cellular iron delivery protein not only expand our thinking on the range of contributions of this protein but present an opportunity to target these pathways in cancers. The key question we focus on within this review is whether ferritin modulation represents a useful approach for treating cancers. We discussed novel functions and processes of this protein in cancers. We are not limiting this review to cell intrinsic modulation of ferritin in cancers, but also focus on its utility in the trojan horse approach in cancer therapeutics. The novel functions of ferritin as discussed herein realize the multiple roles of ferritin in cell biology that can be probed for therapeutic opportunities and further research.

Acrylamide induces human chondrocyte cell death by initiating autophagy‑dependent ferroptosis

Acrylamide (ACR) is formed during heat treatment of foodstuffs and ACR may serve as a probable malignant neoplastic disease agent in all organs and tissues of the human body. However, it is unknown if ACR is associated with ankylosing spondylitis (AS) pathogenesis. Cell viability and proliferation were determined using CCK-8 assay and EdU staining. Flow cytometry was used to determine cell death and cell cycle arrest. Intracellular lipid reactive oxygen species, Fe²⁺ and mitochondrial membrane potential (MMP) were analyzed using a C11-BODIPY581/591 fluorescent probe, FerroOrange staining and a JC-1 MMP Assay kit, respectively. The present study showed that ACR decreased chondrocyte cell viability in a dose-dependent manner and that ACR significantly promoted chondrocyte senescence. ACR also elevated the expression of cell cycle arrest-associated proteins, including p53, cyclin-dependent kinase inhibitor 1 and cyclin-dependent kinase inhibitor protein, in human chondrocytes. Similarly, DNA damage was also enhanced following ACR treatment in chondrocytes. In addition, the ferroptosis-specific inhibitor ferrostatin-1 (Fer-1) and the autophagy inhibitor 3-methyladenine abolished ACR-induced cell death in chondrocytes. ACR was shown to activate autophagic flux and induce mitochondrial dysfunction by increasing the MMP. Western blot analysis of ferroptosis-related proteins demonstrated that ACR decreased the expression of glutathione peroxidase 4, solute carrier family 7 member 11, transferrin receptor protein 1 and ferritin heavy chain 1 in chondrocytes whereas Fer-1 abolished these effects. ACR treatment significantly elevated the phosphorylation levels of AMP-activated protein kinase (AMPK) and serine/threonine-protein kinase ULK1 in human chondrocytes. Notably, the effect of ACR was diminished by knockdown of AMPK, as evidenced by reduced lipid reactive oxygen species accumulation and Fe²⁺ levels. Hence, ACR inhibited cell proliferation and contributed to cell death by inducing autophagy-dependent ferroptosis while promoting autophagy by activating AMPK-ULK1-mTOR signaling in human chondrocytes. It was hypothesized that the presence of ACR in foodstuffs may increase the risk of AS and that decreasing ACR in food products is of importance.

Pyroptosis, ferroptosis, and autophagy cross-talk in glioblastoma opens up new avenues for glioblastoma treatment

Glioma is a common primary tumor of the central nervous system (CNS), with glioblastoma multiforme (GBM) being the most malignant, aggressive, and drug resistant. Most drugs are designed to induce cancer cell death, either directly or indirectly, but malignant tumor cells can always evade death and continue to proliferate, resulting in a poor prognosis for patients. This reflects our limited understanding of the complex regulatory network that cancer cells utilize to avoid death. In addition to classical apoptosis, pyroptosis, ferroptosis, and autophagy are recognized as key cell death modalities that play significant roles in tumor progression. Various inducers or inhibitors have been discovered to target the related molecules in these pathways, and some of them have already been translated into clinical treatment. In this review, we summarized recent advances in the molecular mechanisms of inducing or inhibiting pyroptosis, ferroptosis, or autophagy in GBM, which are important for treatment or drug tolerance. We also discussed their links with apoptosis to better understand the mutual regulatory network among different cell death processes. Video Abstract.

Identification of a m6A-related ferroptosis signature as a potential predictive biomarker for lung adenocarcinoma

BACKGROUND

Both N6-methyladenosine (m⁶A) and ferroptosis-related genes are associated with the prognosis of lung adenocarcinoma. However, the predictive value of m⁶A-related ferroptosis genes remains unclear. Here, we aimed to identify the prognostic value of m⁶A-related ferroptosis genes in lung adenocarcinoma.

METHODS

Lung adenocarcinoma sample data were downloaded from the University of California Santa Cruz Xena and Gene Expression Omnibus databases. Spearman's correlation analysis was used to screen for m⁶A-related ferroptosis genes. Univariate Cox regression, Kaplan-Meier, and Lasso analyses were conducted to identify prognostic m⁶A-related ferroptosis genes, and stepwise regression was used to construct a prognostic gene signature. The predictive value of the gene signature was assessed using a multivariate Cox analysis. In the validation cohort, survival analysis was performed to verify gene signature stability. The training cohort was divided into high- and low-risk groups according to the median risk score to assess differences between the two groups in terms of gene set variation analysis, somatic mutations, and tumor immune infiltration cells.

RESULTS

Six m⁶A-related ferroptosis genes were used to construct a gene signature in the training cohort and a multivariate Cox analysis was conducted to determine the independent prognostic value of these genes in lung adenocarcinoma. In the validation cohort, Kaplan-Meier and receiver operating characteristic analyses confirmed the strong predictive power of this signature for the prognosis of lung adenocarcinoma. Gene set variation analysis showed that the low-risk group was mainly related to immunity, and the high-risk group was mainly related to DNA replication. Somatic mutation analysis revealed that the TP53 gene had the highest mutation rate in the high-risk group. Tumor immune infiltration cell analysis showed that the low-risk group had higher levels of resting CD4 memory T cells and lower levels of M0 macrophages.

CONCLUSION

Our study identified a novel m⁶A-related ferroptosis-associated six-gene signature (comprising SLC2A1, HERPUD1, EIF2S1, ACSL3, NCOA4, and CISD1) for predicting lung adenocarcinoma prognosis, yielding a useful prognostic biomarker and potential therapeutic target.

Identification of iron metabolism-related predictive markers of endometriosis and endometriosis-relevant ovarian cancer

Endometriosis is associated with ovarian cancers, mainly endometrioid and clear-cell carcinomas. Iron metabolism has been shown to play a role in endometriosis. Therefore, it is vital to explore the relationship between iron metabolism and ovarian cancer and to identify novel markers for diagnostics and therapeutics. The endometriosis dataset GSE51981 and the ovarian cancer dataset GSE26712 were obtained from the gene expression omnibus database, and differentially expressed genes were identified. Iron metabolism genes were obtained from molecular signatures database, and hub genes from the 3 datasets were obtained. Seven hub genes were identified by bioinformatic analysis, and 3 hub genes (NCOA4, ETFDH, and TYW1) were further selected by logistic regression, which were verified in an independent endometriosis dataset (GSE25628) and ovarian cancer dataset (GSE14407), showing good predictive diagnostic value (area under the receiver operating characteristic curve of 0.88 and 0.9, respectively). Gene Ontology, gene set enrichment analysis, and immune infiltration analysis further confirmed the related functions, pathways, and immune relationship between iron metabolism and ovarian cancer. This study highlights the potential of targeting iron metabolism in the prevention of potential ovarian cancer and in the further exploration of endometriosis and endometriosis-relevant ovarian cancer therapeutics.

A Comprehensive Pan-Cancer Analysis of the Regulation and Prognostic Effect of Coat Complex Subunit Zeta 1

The Coatomer protein complex Zeta 1 (COPZ1) has been reported to play an essential role in maintaining the survival of some types of tumors. In this study, we sought to explore the molecular characteristics of COPZ1 and its clinical prognostic value through a pan-cancers bioinformatic analysis. We found that COPZ1 was extremely prevalent in a variety of cancer types, and high expression of COPZ1 was linked to poor overall survival in many cancers, while low expression in LAML and PADC was correlated with tumorigenesis. Besides, the CRISPR Achilles' knockout analysis revealed that COPZ1 was vital for many tumor cells' survival. We further demonstrated that the high expression level of COPZ1 in tumors was regulated in multi-aspects, including abnormal CNV, DNA-methylation, transcription factor and microRNAs. As for the functional exploration of COPZ1, we found a positive relationship between COPZ1's expression and stemness and hypoxia signature, especially the contribution of COPZ1 on EMT ability in SARC. GSEA analysis revealed that COPZ1 was associated with many immune response pathways. Further investigation demonstrated that COPZ expression was negatively correlated with immune score and stromal score, and low expression of COPZ1 has been associated to more antitumor immune cell infiltration and pro-inflammatory cytokines. The further analysis of COPZ1 expression and anti-inflammatory M2 cells showed a consistent result. Finally, we verified the expression of COPZ1 in HCC cells, and proved its ability of sustaining tumor growth and invasion with biological experiments. Our study provides a multi-dimensional pan-cancer analysis of COPZ and demonstrates that COPZ1 can serve as both a prospective target for the treatment of cancer and a prognostic marker for a variety of cancer types.

RNA-binding proteins in degenerative joint diseases: A systematic review

RNA-binding proteins (RBPs), which are conserved proteins comprising multiple intermediate sequences, can interact with proteins, messenger RNA (mRNA) of coding genes, and non-coding RNAs to perform different biological functions, such as the regulation of mRNA stability, selective polyadenylation, and the management of non-coding microRNA (miRNA) synthesis to affect downstream targets. This article will highlight the functions of RBPs, in degenerative joint diseases (intervertebral disc degeneration [IVDD] and osteoarthritis [OA]). It will reviews the latest advancements on the regulatory mechanism of RBPs in degenerative joint diseases, in order to understand the pathophysiology, early diagnosis and treatment of OA and IVDD from a new perspective.

A Data-Mining Approach to Identify NF-kB-Responsive microRNAs in Tissues Involved in Inflammatory Processes: Potential Relevance in Age-Related Diseases

The nuclear factor NF-kB is the master transcription factor in the inflammatory process by modulating the expression of pro-inflammatory genes. However, an additional level of complexity is the ability to promote the transcriptional activation of post-transcriptional modulators of gene expression as non-coding RNA (i.e., miRNAs). While NF-kB’s role in inflammation-associated gene expression has been extensively investigated, the interplay between NF-kB and genes coding for miRNAs still deserves investigation. To identify miRNAs with potential NF-kB binding sites in their transcription start site, we predicted miRNA promoters by an in silico analysis using the PROmiRNA software, which allowed us to score the genomic region’s propensity to be miRNA cis-regulatory elements. A list of 722 human miRNAs was generated, of which 399 were expressed in at least one tissue involved in the inflammatory processes. The selection of “high-confidence” hairpins in miRbase identified 68 mature miRNAs, most of them previously identified as inflammamiRs. The identification of targeted pathways/diseases highlighted their involvement in the most common age-related diseases. Overall, our results reinforce the hypothesis that persistent activation of NF-kB could unbalance the transcription of specific inflammamiRNAs. The identification of such miRNAs could be of diagnostic/prognostic/therapeutic relevance for the most common inflammatory-related and age-related diseases.

The Interplay Between Autophagy and Regulated Necrosis

Significance: Autophagy is critical to cellular homeostasis. Emergence of the concept of regulated necrosis, such as necroptosis, ferroptosis, pyroptosis, and mitochondrial membrane-permeability transition (MPT)-derived necrosis, has revolutionized the research into necrosis. Both altered autophagy and regulated necrosis contribute to major human diseases. Recent studies reveal an intricate interplay between autophagy and regulated necrosis. Understanding the interplay at the molecular level will provide new insights into the pathophysiology of related diseases. Recent Advances: Among the three forms of autophagy, macroautophagy is better studied for its crosstalk with regulated necrosis. Macroautophagy seemingly can either antagonize or promote regulated necrosis, depending upon the form of regulated necrosis, the type of cells or stimuli, and other cellular contexts. This review will critically analyze recent advances in the molecular mechanisms governing the intricate dialogues between macroautophagy and main forms of regulated necrosis. Critical Issues: The dual roles of autophagy, either pro-survival or pro-death characteristics, intricate the mechanistic relationship between autophagy and regulated necrosis at molecular level in various pathological conditions. Meanwhile, key components of regulated necrosis are also involved in the regulation of autophagy, which further complicates the interrelationship. Future Directions: Resolving the controversies over causation between altered autophagy and a specific form of regulated necrosis requires approaches that are more definitive, where rigorous evaluation of autophagic flux and the development of more reliable and specific methods to quantify each form of necrosis will be essential. The relationship between chaperone-mediated autophagy or microautophagy and regulated necrosis remains largely unstudied. Antioxid. Redox Signal. 38, 550-580.

Autophagy-dependent ferroptosis as a potential treatment for glioblastoma

Glioblastoma (GBM) is the most common malignant primary brain tumor with a poor 5-year survival rate. Autophagy is a conserved intracellular degradation system that plays a dual role in GBM pathogenesis and therapy. On one hand, stress can lead to unlimited autophagy to promote GBM cell death. On the other hand, elevated autophagy promotes the survival of glioblastoma stem cells against chemotherapy and radiation therapy. Ferroptosis is a type of lipid peroxidation-mediated regulated necrosis that initially differs from autophagy and other types of cell death in terms of cell morphology, biochemical characteristics, and the gene regulators involved. However, recent studies have challenged this view and demonstrated that the occurrence of ferroptosis is dependent on autophagy, and that many regulators of ferroptosis are involved in the control of autophagy machinery. Functionally, autophagy-dependent ferroptosis plays a unique role in tumorigenesis and therapeutic sensitivity. This mini-review will focus on the mechanisms and principles of autophagy-dependent ferroptosis and its emerging implications in GBM.

Prognostic Prediction Model for Glioblastoma: A Ferroptosis-Related Gene Prediction Model and Independent External Validation

Glioblastoma (GBM) is the most common primary malignant intracranial tumor with a poor prognosis. Ferroptosis is a newly discovered, iron-dependent, regulated cell death, and recent studies suggest its close correlation to GBM. The transcriptome and clinical data were obtained for patients diagnosed with GBM from TCGA, GEO, and CGGA. Ferroptosis-related genes were identified, and a risk score model was constructed using Lasso regression analyses. Survival was evaluated by univariate or multivariate Cox regressions and Kaplan-Meier analyses, and further analyses were performed between the high- and low-risk groups. There were 45 ferroptosis-related different expressed genes between GBM and normal brain tissues. The prognostic risk score model was based on four favorable genes, CRYAB, ZEB1, ATP5MC3, and NCOA4, and four unfavorable genes, ALOX5, CHAC1, STEAP3, and MT1G. A significant difference in OS between high- and low-risk groups was observed in both the training cohort (p < 0.001) and the validation cohorts (p = 0.029 and 0.037). Enrichment analysis of pathways and immune cells and functioning was conducted between the two risk groups. A novel prognostic model for GBM patients was developed based on eight ferroptosis-related genes, suggesting a potential prediction effect of the risk score model in GBM.

Progress in targeting PTEN/PI3K/Akt axis in glioblastoma therapy: Revisiting molecular interactions

Glioblastoma (GBM) is one of the most malignant cancers of central nervous system and due to its sensitive location, surgical resection has high risk and therefore, chemotherapy and radiotherapy are utilized for its treatment. However, chemoresistance and radio-resistance are other problems in GBM treatment. Hence, new therapies based on genes are recommended for treatment of GBM. PTEN is a tumor-suppressor operator in cancer that inhibits PI3K/Akt/mTOR axis in diminishing growth, metastasis and drug resistance. In the current review, the function of PTEN/PI3K/Akt axis in GBM progression is evaluated. Mutation or depletion of PTEN leads to increase in GBM progression. Low expression level of PTEN mediates poor prognosis in GBM and by increasing proliferation and invasion, promotes malignancy of tumor cells. Moreover, loss of PTEN signaling can result in therapy resistance in GBM. Activation of PTEN signaling impairs GBM metabolism via glycolysis inhibition. In contrast to PTEN, PI3K/Akt signaling has oncogenic function and during tumor progression, expression level of PI3K/Akt enhances. PI3K/Akt signaling shows positive association with oncogenic pathways and its expression similar to PTEN signaling, is regulated by non-coding RNAs. PTEN upregulation and PI3K/Akt signaling inhibition by anti-cancer agents can be beneficial in interfering GBM progression. This review emphasizes on the signaling networks related to PTEN/PI3K/Akt and provides new insights for targeting this axis in effective GBM treatment.

Mechanism of YY1 mediating autophagy dependent ferroptosis in PM2.5 induced cardiac fibrosis

Epidemiological studies have demonstrated strong associations between exposure to ambient fine particulate matter (PM2.5) and cardiac disease. To investigate the potential mechanism of cardiac fibrosis induced by PM2.5, we established PM2.5 exposure models in vivo and in vitro, and then cardiac fibrosis was evaluated. The ferroptosis and ferritinophagy was detected to characterize the effects of PM2.5 exposure. The results indicated that PM2.5 exposure could induce cardiac fibrosis in mice. YY1 was induced by PM2.5 exposure and then increased NCOA4, a cargo receptor for ferritinophagy, which interacted with FHC and promoted the transport of ferritin to the autophagosome for degradation. The release of large amounts of free iron from ferritinophagy led to lipid peroxidation directly via the Fenton reaction, thereby triggering ferroptosis. Moreover, siNCOA4 could partly restore the FHC protein level in HL-1 cells and inhibit the occurrence of downstream ferroptosis. Functionally, NCOA4 knockdown inhibited ferroptosis and alleviated HL-1 cell death induced by PM2.5. Ferroptosis inhibitor (Ferrostatin-1) could reverse the promoting effect of ferritinophagy mediated ferroptosis on cardiac fibrosis induced by PM2.5 exposure in mice. Our study indicated that PM2.5 induced cardiac fibrosis through YY1 regulating ferritinophagy-dependent ferroptosis.

The m6A Reader YTHDF1 Promotes Lung Carcinoma Progression via Regulating Ferritin Mediate Ferroptosis in an m6A-Dependent Manner

N6-methyladenosine (m6A) plays a significant role as an epigenetic mechanism, which is involved in various cancers' progress via regulating mRNA modification. As a crucial m6A "reader", YTHDF1 is able to alter m6A-modified mRNA and promote the protein translation process in multiple cancers. However, the role of YTHDF1 in lung cancer has not been fully investigated. This study focuses on elucidating the function of YTHDF1 in the development of lung cancer and its underlying mechanism. We demonstrated that YTHDF1 was highly expressed in lung carcinoma progression; then, the loss of function experiments in lung cell lines confirmed that knockdown of YTHDF1 suppressed cell proliferation, migration and invasion and induced ferroptosis of lung cancer cells. Further functional assays showed that ferritin (FTH) was identified as the key target of YTHDF1 in lung cancer cells. Furthermore, the overexpression of ferritin in YTHDF1-depleted cells partially restored lung cancer cell suppression. Collectively, our data suggested that the upregulation of YTHDF1 promotes lung cancer carcinogenesis by accelerating ferritin translation in an m6A-dependent manner. We hope that our findings may provide a new target for lung cancer diagnosis and treatment.