YAP/TAZ and ATF4 drive resistance to Sorafenib in hepatocellular carcinoma by preventing ferroptosis

Ferroptosis and hearing loss: from molecular mechanisms to therapeutic interventions

Hearing loss profoundly affects social engagement, mental health, cognition, and brain development, with sensorineural hearing loss (SNHL) being a major concern. Linked to ototoxic medications, ageing, and noise exposure, SNHL presents significant treatment challenges, highlighting the need for effective prevention and regeneration strategies. Ferroptosis, a distinct form of cell death featuring iron-dependent lipid peroxidation, has garnered interest due to its potential role in cancer, ageing, and neuronal degeneration, especially hearing loss. The emerging role of ferroptosis as a crucial mediator in SNHL suggests that it may offer a novel therapeutic target for otoprotection. This review aims to summarise the intricate connection between ferroptosis and SNHL, offering a fresh perspective for exploring targeted therapeutic strategies that could potentially mitigate cochlear cells damage and enhance the quality of life for individuals with hearing impairments.

YAP-mediated DDX3X confers resistance to ferroptosis in breast cancer cells by reducing lipid peroxidation

Metabolic shifts in cancer cells were found to participate in tumorigenesis, especially driving chemotherapeutic resistance. Ferroptosis is a newly discovered form of cell death induced by excessive accumulations of iron and lipid peroxidation. Susceptibility to ferroptosis can be intrinsically regulated by various cellular metabolic pathways. Therefore, inducing ferroptosis might be a promising anticancer therapeutic strategy. DEAD-box helicase 3 X-linked (DDX3X), a critical modulator of RNA metabolism, was identified as an oncogene in breast cancer and also participates in cancer metabolism and chemotherapeutic resistance. However, the molecular regulation of the association between DDX3X and ferroptosis is largely unknown. Herein, we investigated the correlation between resistance to ferroptosis and DDX3X expression in breast cancer cells. We found that elevation of DDX3X was associated with increased resistance to a ferroptosis inducer in breast cancer cells, and manipulating DDX3X expression regulated the sensitivity to the ferroptosis inducer. Importantly, DDX3X upregulated expression of the anti-ferroptotic enzyme glutathione peroxidase 4 (GPX4) gene to confer ferroptosis resistance in breast cancer cells. Moreover, DDX3X was transcriptionally upregulated by the yes-associated protein (YAP). Knockdown of YAP downregulated DDX3X mRNA expression and facilitated lipid peroxidation, but that were restored in the presence of DDX3X. Clinically, coexpression of DDX3X and YAP was found in a variety of malignancy, and their elevation conferred poor survival prognosis in patients with breast cancer. Together, our findings reveal the crucial role of DDX3X in sensitivity to ferroptosis and underscore its potential as a diagnostic marker and therapeutic target. DDX3X renders resistance to ferroptosis and plays a role in mitigating lipid peroxidation, paving the way for therapeutic vulnerability via targeting cancer metabolism.

Sorafenib resistance and therapeutic strategies in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains one of the most prevalent and lethal cancers globally. While surgical resection and liver transplantation offer potential cures for early-stage HCC, the majority of patients are diagnosed at advanced stages where such interventions are not viable. Sorafenib, a multi-target kinase inhibitor, has been a cornerstone in the treatment of advanced HCC since its approval in 2007. Despite its significant clinical impact, less than half of the treated patients derive long-term benefits due to the emergence of resistance and associated side effects. This review focuses on the role of sorafenib, an FDA-approved multi-target kinase inhibitor, in treating advanced HCC, discusses the mechanisms underlying its therapeutic effects and associated resistance, and explores additional therapeutic strategies being investigated to improve patient outcomes.

Cross-talks of GSH, mitochondria, RNA m6A modification, NRF2, and p53 between ferroptosis and cuproptosis in HCC: A review

Hepatocellular carcinoma (HCC) is a common malignant tumor with high morbidity and mortality, as well as poor prognosis. Therefore, it is imperative to explore alternative therapeutic targets for HCC treatment. Ferroptosis and cuproptosis have recently been identified as metal-dependent cell death mechanisms that play significant roles in HCC treatment. This study identified potential cross-talk between ferroptosis and cuproptosis, including the common hub glutathione, common site of occurrence, mitochondria, shared epigenetic modification mode, RNA N6 methyladenosine modification, mutual inhibitor, nuclear factor erythroid 2-related factor 2, and dual regulator, p53. These findings provide a theoretical foundation for the joint induction of HCC cell death and effective inhibition of HCC progression. However, some immune cells are susceptible to ferroptosis or cuproptosis, which may impair or enhance anti-cancer immune function. We propose strategies to target specific targets molecules such as tripartite motif containing 25, ferroptosis suppressor protein 1, and peroxisome proliferator-activated receptor gamma or exploit the unique acidic environment surrounding cancer cells to precisely induce ferroptosis in cancer cells. This approach aims to advance the development of precision medicine for HCC treatment.

Deciphering Ferroptosis: From Molecular Pathways to Machine Learning-Guided Therapeutic Innovation

Ferroptosis is a unique form of cell death reliant on iron and lipid peroxidation. It disrupts redox balance, causing cell death by damaging the plasma membrane, with inducers acting through enzymatic pathways or transport systems. In cancer treatment, suppressing ferroptosis or circumventing it holds significant promise. Beyond cancer, ferroptosis affects aging, organs, metabolism, and nervous system. Understanding ferroptosis mechanisms holds promise for uncovering novel therapeutic strategies across a spectrum of diseases. However, detection and regulation of this regulated cell death are still mired with challenges. The dearth of cell, tissue, or organ-specific biomarkers muted the pharmacological use of ferroptosis. This review covers recent studies on ferroptosis, detailing its properties, key genes, metabolic pathways, and regulatory networks, emphasizing the interaction between cellular signaling and ferroptotic cell death. It also summarizes recent findings on ferroptosis inducers, inhibitors, and regulators, highlighting their potential therapeutic applications across diseases. The review addresses challenges in utilizing ferroptosis therapeutically and explores the use of machine learning to uncover complex patterns in ferroptosis-related data, aiding in the discovery of biomarkers, predictive models, and therapeutic targets. Finally, it discusses emerging research areas and the importance of continued investigation to harness the full therapeutic potential of targeting ferroptosis.

Protocadherin 17 weakens the lenvatinib resistance of liver cancer through inducing ferroptosis

Lenvatinib has been employed in the treatment of advanced liver cancer; however, its clinical application is significantly impeded by frequent drug resistance. Recent studies have revealed that lenvatinib treatment triggers ferroptosis in liver cancer cells, providing a novel approach to addressing lenvatinib resistance. In this study, we initially validated the induction of ferroptosis by lenvatinib in liver cancer cells. Remarkably, protocadherin 17 (PCDH17), an adhesion-related protein, was found to be down-regulated in liver cancer, and overexpression of PCDH17 could induce ferroptosis in liver cancer cells. Importantly, silencing PCDH17 inhibited the impact of lenvatinib on liver cancer cell ferroptosis, while overexpression of PCDH17 had the opposite effect. These findings were further confirmed using a xenograft tumor model in BALB/c nude mice. Additionally, lenvatinib-resistant (LR) liver cancer cells were generated for additional validation purposes. It was observed that LR-liver cancer cells lost their susceptibility to ferroptosis induction by lenvatinib; however, overexpression of PCDH17 reactivated their sensitivity to ferroptosis. Corresponding results were also verified in BALB/c nude mice models. In conclusion, these results suggest that as a novel regulator of ferroptosis, PCDH17 can alleviate lenvatinib resistance and potentially enhance the therapeutic efficacy of lenvatinib in treating liver cancer.

The Role and Mechanisms of Ubiquitin-Proteasome System-Mediated Ferroptosis in Neurological Disorders

Ferroptosis is a form of cell death elicited by an imbalance in intracellular iron concentrations, leading to enhanced lipid peroxidation. In neurological disorders, both oxidative stress and mitochondrial damage can contribute to ferroptosis, resulting in nerve cell dysfunction and death. The ubiquitin-proteasome system (UPS) refers to a cellular pathway in which specific proteins are tagged with ubiquitin for recognition and degradation by the proteasome. In neurological conditions, the UPS plays a significant role in regulating ferroptosis. In this review, we outline how the UPS regulates iron metabolism, ferroptosis, and their interplay in neurological diseases. In addition, we discuss the future application of small-molecule inhibitors and identify potential drug targets. Further investigation into the mechanisms of UPS-mediated ferroptosis will provide novel insights and strategies for therapeutic interventions and clinical applications in neurological diseases.

BEND3 promotes hepatocellular carcinoma progression and metastasis by activating the PI3K/AKT/mTOR pathway and inducing epithelial-mesenchymal transition

OBJECTIVE

This study aimed to investigate the expression of BEND3 in hepatocellular carcinoma (HCC), its correlation with clinical characteristics, and its functional and mechanistic impacts on HCC progression.

METHODS

Bioinformatics analyses identified BEND3 as highly expressed in HCC and associated with poor clinical prognosis, which was further validated using qRT-PCR, western blotting and immunohistochemistry. Stable BEND3-overexpressing and silenced cell lines were constructed to evaluate its functional effects. CCK-8 and colony formation assays assessed its influence on cell proliferation, while wound healing and Transwell assays evaluated its role in migration and invasion. WB and immunofluorescence were employed to analyze the effects of BEND3 on epithelial-mesenchymal transition (EMT) and the PI3K/AKT/mTOR signaling pathway.

RESULTS

Public database analysis, alongside qRT-PCR, western blotting, and immunohistochemical, confirmed that BEND3 expression is significantly elevated in HCC tissues compared to normal liver tissues and is closely associated with poor prognosis. Functional assays demonstrated that BEND3 promotes HCC cell proliferation, migration, and invasion. Mechanistic studies revealed that BEND3 drives HCC progression by inducing EMT and activating the PI3K/AKT/mTOR signaling pathway.

CONCLUSION

BEND3 is highly expressed in HCC and strongly correlates with poor clinical outcomes. Functional and mechanistic analyses indicate that BEND3 enhances HCC progression by promoting proliferation, migration and invasion via EMT induction and PI3K/AKT/mTOR pathway activation.

EOGT knockdown promotes ferroptosis and inhibits hepatocellular carcinoma proliferation by regulating SLC7A11 via HEY1

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality, characterized by a complex molecular landscape. EGF Domain Specific O-linked β-N-acetylglucosamine transferase (EOGT) functions as an O-GlcNAc transferase with specific activity towards proteins containing epidermal growth factor (EGF) repeats. Although it is known to potentially play an oncogenic role in HCC, the exact mechanisms remain unclear. Induction of ferroptosis is a primary mechanism by which anticancer drugs such as sorafenib treat HCC. This study aimed to elucidate the expression profile of EOGT in HCC and its relationship with ferroptosis, as well as to investigate the underlying molecular mechanisms.

METHODS

Utilizing bioinformatics resources, we explored the potential role of EOGT in HCC. The effects of EOGT on HCC cell behavior were examined using cell models and subcutaneous xenograft models in nude mice. Further insights into the molecular mechanisms were obtained through RNA-seq in cell models, hydrodynamic modeling in mice, Western blotting, chromatin immunoprecipitation (ChIP) sequencing, and dual-luciferase reporter assays to analyze the interaction between HEY1 and SLC7A11. Multiple validation steps were employed to thoroughly investigate the roles of these factors in the regulation of ferroptosis in HCC.

RESULTS

Our findings revealed that EOGT is upregulated in HCC and correlates with poor prognosis and drug resistance. Knockdown of EOGT inhibited HCC cell proliferation and enhanced sensitivity to ferroptosis by downregulating SLC7A11, a process mediated by HEY1. These results were confirmed by cell viability assays, quantitative real-time PCR (qPCR), Western blotting, and dual-luciferase reporter gene assays.

CONCLUSIONS

EOGT promotes HCC proliferation and inhibits ferroptosis by modulating the HEY1-SLC7A11 axis, suggesting a potential therapeutic target for HCC treatment.

ESR1-dependent suppression of LCN2 transcription reverses autophagy-linked ferroptosis and enhances sorafenib sensitivity in hepatocellular carcinoma

Sorafenib resistance is a significant hurdle in the treatment landscape of hepatocellular carcinoma (HCC). Lipocalin 2 (LCN2), a secretory glycoprotein that transports lipophilic molecules across cell membranes, is thought to affect the s therapeutic efficacy of sorafenib. Despite its importance, the detailed regulatory pathways involving LCN2 are still being deciphered. We probed the correlation between LCN2 expression and sorafenib resistance in HCC cells. Through the modulation of LCN2 levels, we investigated its role in cell proliferation, apoptosis, and its regulatory effects on autophagy-driven ferroptosis. With the aid of hTFtarget and JASPAR databases, ESR1 was pinpointed as a transcriptional inhibitor of LCN2. The impact of the ESR1-LCN2 axis on sorafenib resistance in HCC was then examined in vitro and validated in a xenograft tumor mouse model. In HCC cells, elevated LCN2 levels were found to be associated with resistance to sorafenib. Depletion of LCN2 resulted in attenuated HCC cell growth and elevated rates of apoptosis and ferroptosis. Overexpression of LCN2 had the opposite effect, promoting cell proliferation and suppressing cell death pathways, a response that could be overridden by autophagy agonists. ESR1 suppressed LCN2 transcription, which in turn activated autophagy-mediated ferroptosis, mitigating sorafenib tolerance in HCC and enhancing the therapeutic index. ESR1 targets LCN2 transcription to initiate autophagy-driven ferroptosis, thereby reducing sorafenib resistance in HCC cells.

The glutamine starvation-induced lncRNA FERRIN suppresses ferroptosis via the stabilization of SLC7A11 mRNA

As an essential nutrient for cancer cell survival, glutamine plays both promoting and inhibitory roles in ferroptosis; however, the underlying mechanisms remain obscure. Emerging evidence suggests that long noncoding RNAs (lncRNAs) are crucial regulators of ferroptosis. Nevertheless, it remains unclear whether lncRNAs are involved in glutamine-regulated ferroptosis. In this study, we report that the lncRNA FERRIN is induced by the transcription factor ATF4 under glutamine starvation conditions. FERRIN functions as an inhibitor of ferroptosis by upregulating SLC7A11 expression. Mechanistically, FERRIN interacts with the RNA binding protein hnRNPK, facilitating its binding to SLC7A11 mRNA and leading to the stabilization of SLC7A11 mRNA. Consistent with its inhibitory role in ferroptosis, FERRIN promotes in vitro cancer cell proliferation and in vivo xenograft tumor growth through its modulation of SLC7A11. Collectively, these findings establish FERRIN as a critical negative regulator of ferroptosis and suggest that FERRIN may represent an important link between glutamine availability and ferroptosis.

Unraveling the triad of hypoxia, cancer cell stemness, and drug resistance

In the domain of addressing cancer resistance, challenges such as limited effectiveness and treatment resistance remain persistent. Hypoxia is a key feature of solid tumors and is strongly associated with poor prognosis in cancer patients. Another significant portion of the development of acquired drug resistance is attributed to tumor stemness. Cancer stem cells (CSCs), a small tumor cell subset with self-renewal and proliferative abilities, are crucial for tumor initiation, metastasis, and intra-tumoral heterogeneity. Studies have shown a significant association between hypoxia and CSCs in the context of tumor resistance. Recent studies reveal a strong link between hypoxia and tumor stemness, which together promote tumor survival and progression during treatment. This review elucidates the interplay between hypoxia and CSCs, as well as their correlation with resistance to therapeutic drugs. Targeting pivotal genes associated with hypoxia and stemness holds promise for the development of novel therapeutics to combat tumor resistance.

Optimizing interventional therapy: A homogeneous lipiodol formulation of Tirapazamine and Sorafenib responsive to post-embolization microenvironment

Transcatheter arterial chemoembolization (TACE) is the principal treatment option for patients with unresectable hepatocellular carcinoma (HCC). However, the hypoxic microenvironment following TACE can promote angiogenesis and suppress tumor ferroptosis, resulting in an unfavorable prognosis. Tirapazamine (TPZ), a hypoxia-activated prodrug with specific cytotoxicity for hypoxic cells, making it a potential candidate for TACE. To develop an effective hypoxia-responsive drug delivery platform for TACE, we propose a novel lipiodol embolic formulation that integrates TPZ and sorafenib (SFB) by super-stable homogeneous intermixed formulation technology (SHIFT). This approach achieves the manufacture of embolic agents with stable drug dispersion characteristics, fulfilling the need for sustained drug release in TACE. The prolonged tumor penetration of TPZ exhibited embolization-responsive tumor killing, and its combination with SFB can suppress hypoxia-induced angiogenesis and trigger tumor ferroptosis, maintaining low oxygen levels, thereby boosting the therapeutic efficacy of TPZ. Conversely, TPZ can combat the resistance to SFB in hypoxic tumor cells. In summary, this study developed a novel embolization drug formulation based on embolic hypoxic microenvironment. The synergistic mechanism of TPZ and SFB enhances the therapeutic effects of hypoxia-activated prodrugs and mitigates the adverse effects of hypoxia.

Polysaccharides from maggot extracts suppressed colorectal cancer progression by inducing ferroptosis via HMOX1/GPX4 signaling pathway

Maggots contain various kinds of polysaccharides and recent studies mostly concentrated on their anti-inflammatory functions. While the molecule mechanisms related to the polysaccharides inhibiting carcinogenesis remains unclear. Here we characterized the polysaccharides extracted from maggot (MEs) determining their anti-colon cancer potentials. ME in this study were composed of glucose, mannose, galactose, arabinose and xylose. ME dose-and time-dependently inhibited viability and obviously induced G0/G1 phase arrest in human colon cancer cells. Additionally, Proteomics and western blotting proved that ME suppressed the expression of GPX4 and increased the expression of HMOX1 in vivo and vitro. ME promoted ferroptosis in HCT116 and LOVO cells, reversing ROS, lipid peroxidation and GSSG/GSH radio level. In general, the findings stated that the polysaccharides provided effects of inducing colon cancer ferroptosis, uncovering potential function of ME from maggot as a candidate compound.

Emerging insights into the role of microRNAs regulation of ferroptosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major type of liver cancer and an important cause of cancer death. It has been reported that the hepatocyte death plays an important role in HCC. Ferroptosis is an iron-dependent programmed cell death characterized by the accumulation of free iron and lipid peroxidation. A series of studies have shown that ferroptosis contributes to the occurrence and development of HCC. MicroRNAs (miRNAs) are non-coding RNAs with a length of approximately 222 nt. In recent years, miRNAs have been shown to participate in regulating ferroptosis to play a vital role in HCC, but the related mechanisms are not fully understood. This review summarized the current understanding of ferroptosis, as well as the biogenesis and function of miRNAs, and focused on the role of miRNAs regulation of ferroptosis in HCC, with the hope of providing new targets and ideas for the treatment of HCC.

Iron homeostasis and ferroptosis in muscle diseases and disorders: mechanisms and therapeutic prospects

The muscular system plays a critical role in the human body by governing skeletal movement, cardiovascular function, and the activities of digestive organs. Additionally, muscle tissues serve an endocrine function by secreting myogenic cytokines, thereby regulating metabolism throughout the entire body. Maintaining muscle function requires iron homeostasis. Recent studies suggest that disruptions in iron metabolism and ferroptosis, a form of iron-dependent cell death, are essential contributors to the progression of a wide range of muscle diseases and disorders, including sarcopenia, cardiomyopathy, and amyotrophic lateral sclerosis. Thus, a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention. This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury, as well as associated muscle diseases and disorders. Moreover, we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders. Finally, we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.

Cancer ATF4-mediated CD58 endocytosis impairs anti-tumor immunity and immunotherapy

Co-stimulatory molecules are imperative for CD8+ T cells to eliminate target cell and maintain sustained cytotoxicity. Despite an advanced understanding of the co-stimulatory molecules deficiency that results in tumor escape, the tumor cell-intrinsic mechanisms that regulate co-stimulatory molecules remain enigmatic, and an in-depth dissection could facilitate the improvement of treatment options. To this end, in this study, we report that the deficiency of the critical costimulatory molecule CD58, mediated by the expression of ATF4 in tumor cells, impairs the formation of immunological synapses (IS) and leads to the deterioration of antitumor immune function of CD8+ T cells. Mechanistically, ATF4 transcriptionally upregulated dynamin 1 (DNM1) expression leading to DNM1-dependent endocytosis (DDE)-mediated degradation of CD58. Furthermore, administration of DDE inhibitor prochlorperazine or ATF4 knockdown effectively restored CD58 expression, boosting CD8+ T cell cytotoxicity and immunotherapy efficiency. Thus, our study reveals that ATF4 in tumor cells weakens CD58 expression to interfere with complete IS formation, and indicates potential approaches to improve the cytolytic function of CD8+ T cell in tumor immunotherapy.

Nuclear Overexpression of SAMHD1 Induces M Phase Stalling in Hepatoma Cells and Suppresses HCC Progression by Interacting with the Cohesin Complex

Emerging evidence suggests that the sterile alpha-motif (SAM) and histidine-aspartate (HD) domain-containing protein 1 (SAMHD1) is implicated in various cancers, including hepatocellular carcinoma (HCC). However, its precise role in tumor cells and the underlying mechanisms remain unclear. This study aimed to investigate the expression patterns, prognostic values, and functional role of SAMHD1 in HCC progression. We constructed liver tissue microarrays using tumor and paired paratumor tissue specimens from 187 patients with primary HCC. Our findings indicate that nuclear SAMHD1 protein levels are increased in tumors compared to paratumor tissues. Moreover, nuclear SAMHD1 levels decline in advanced tumor stages, with higher SAMHD1 nuclear staining correlating with favorable prognostic outcomes. Hepatocyte-specific SAMHD1 knockout mice, generated by crossing SAMHD1fl/fl mice with Alb-cre mice, showed accelerated tumor progression in a diethylnitrosamine (DEN)-induced HCC model. In hepatoma cell lines, nuclear overexpression of SAMHD1 inhibited cell proliferation by stalling mitosis, independent of its deoxynucleotide triphosphohydrolase (dNTPase) function. Mechanistically, SAMHD1 interacts with the cohesin complex in nucleus, enhancing sister chromatid cohesion during cell division, which delays metaphase progression. Our findings suggest that nuclear SAMHD1 plays a critical role in slowing HCC progression by regulating mitosis, highlighting its potential as a therapeutic target by manipulating cohesin dynamics.

Important molecular mechanisms in ferroptosis

Ferroptosis is a type of cell death that is caused by the oxidation of lipids and is dependent on the presence of iron. It was first characterized by Brent R. Stockwell in 2012, and since then, research in the field of ferroptosis has rapidly expanded. The process of ferroptosis-induced cell death is genetically, biochemically, and morphologically distinct from other forms of cellular death, such as apoptosis, necroptosis, and non-programmed cell death. Extensive research has been devoted to comprehending the intricate process of ferroptosis and the various factors that contribute to it. While the majority of these studies have focused on examining the effects of lipid metabolism and mitochondria on ferroptosis, recent findings have highlighted the significant involvement of signaling pathways and associated proteins, including Nrf2, P53, and YAP/TAZ, in this process. This review provides a concise summary of the crucial signaling pathways associated with ferroptosis based on relevant studies. It also elaborates on the drugs that have been employed in recent years to treat ferroptosis-related diseases by targeting the relevant signaling pathways. The established and potential therapeutic targets for ferroptosis-related diseases, such as cancer and ischemic heart disease, are systematically addressed.

Dexmedetomidine plays a protective role in sepsis-associated myocardial injury by repressing PRMT5-mediated ferroptosis

Sepsis rapidly contributed to multiorgan failure, most typically damaging the cardiovascular system, and there were no effective treatments. Dexmedetomidine (Dex) has good therapeutic effects on sepsis-induced organ injury. Our work aimed to probe the pharmacological effects of Dex on ferroptosis in sepsis-associated myocardial injury (S-MI) and define underlying mechanism of action. Cardiomyocytes were exposed to lipopolysaccharide (LPS) for mimicking S-MI model in vitro. The septic mice were constructed by cecum ligation and puncture operation. The mRNA and protein expressions were assessed using quantitative real-time polymerase chain reaction or western blot. Cell survival was determined by cell counting kit-8, lactic dehydrogenase release, and flow cytometry assays. 2',7'-Dichlorodihydrofluorescein diacetate staining measured cellular reactive oxygen species level. The secretion levels of inflammatory cytokines, ferroptosis-related indicators were analyzed by enzyme-linked immunosorbent assay. The N6-methyladenosine (m6A) modification level of protein arginine methyltransferase 5 (PRMT5) mRNA was examined by methylated RNA binding protein immunoprecipitation (Me-RIP) assay. The interaction between methyltransferase like 3 (METTL3)/fat mass and obesity-associated protein (FTO) and PRMT5 was analyzed by RNA immunoprecipitation assay. Dex treatment alleviated LPS-induced cardiomyocyte injury and ferroptosis, while these effects of Dex were reversed by Erastin treatment. Mechanically, Dex ameliorated PRMT5 expression in LPS-induced cardiomyocytes by regulating METTL3/FTO catalyzed m6A modification on PRMT5 mRNA. Rescue experiments confirmed that PRMT5 overexpression abolished Dex-mediated inhibitory roles on LPS-induced cardiomyocyte injury and ferroptosis. Moreover, Dex administration alleviated inflammation, ferroptosis, and myocardial injury in septic mice. Taken together, Dex repressed PMRT5 expression in a m6A-dependent manner, thus lightening LPS-triggered ferroptosis to alleviate cardiomyocyte injury.

Identification of PIF1 as a Ferroptosis-Related Prognostic Biomarker Correlated with Immune Infiltration in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver malignancy characterized by high morbidity and mortality. Recently, ferroptosis has been recognized as an important factor in regulating cell growth in HCC. However, the role of ferroptosis-related genes in HCC remains unclear. The SRP119173 dataset from the Sequence Read Archive database was used to screen differentially expressed genes (DEGs) related to ferroptosis. Meanwhile, weighted gene co-expression network analysis was conducted to identify the HCC-related gene modules in the TCGA-liver hepatocellular carcinoma (LIHC) cohort. Next, the candidate genes related to HCC progression and ferroptosis were identified by Venn analysis. Kaplan-Meier, multivariate COX regression, and CIBERSORT analyses were then performed. Our results found that the levels of PIF1 5'-to-3' DNA helicase (PIF1) were notably elevated in HCC tissues relative to normal tissues. Additionally, HCC patients with high PIF1 expression had worse overall survival outcomes than patients with low PIF1 expression. Additionally, the PIF1 gene could independently predict HCC patients' prognosis. Meanwhile, HCC patients with high PIF1 levels had a higher proportion of regulatory T cells (Tregs) and M0 macrophages, as well as higher expression of immune checkpoints such as PD-1 (PDCD1) and PD-L1 (CD274), compared with patients with low PIF1 levels. Our data suggested that a ferroptosis-related gene PIF1 may serve as a potential biomarker for predicting prognosis in HCC patients.

Sorafenib enhanced the function of myeloid-derived suppressor cells in hepatocellular carcinoma by facilitating PPARα-mediated fatty acid oxidation

BACKGROUND

Sorafenib, an FDA-approved drug for advanced hepatocellular carcinoma (HCC), faces resistance issues, partly due to myeloid-derived suppressor cells (MDSCs) that enhance immunosuppression in the tumor microenvironment (TME).

METHODS

Various murine HCC cell lines and MDSCs were used in a series of in vitro and in vivo experiments. These included subcutaneous tumor models, cell viability assays, flow cytometry, immunohistochemistry, and RNA sequencing. MDSCs were analyzed for chemotaxis, immunosuppressive functions, fatty acid oxidation (FAO), and PPARα expression. The impact of sorafenib on tumor growth, MDSC infiltration, differentiation, and immunosuppressive function was assessed, alongside the modulation of these processes by PPARα.

RESULTS

Here, we revealed increased infiltration and enhanced function of MDSCs in TME after treatment with sorafenib. Moreover, our results indicated that sorafenib induced the accumulation of MDSCs mediated by CCR2, and pharmacological blockade of CCR2 markedly reduced MDSCs migration and tumor growth. Mechanistically, sorafenib promoted the effect and fatty acid uptake ability of MDSCs and modulated peroxisome proliferator-activated receptor α (PPARα)-mediated fatty acid oxidation (FAO). In addition, tumor-bearing mice fed a high-fat diet (HFD) at the beginning of sorafenib administration had worse outcomes than mice fed a regular diet. Genetic deficiency of PPARα weakens the effect of sorafenib on MDSCs in mice with HCC. Pharmacological inhibition of PPARα has a synergistic anti-tumor effect with sorafenib, which is attenuated by the inhibition of MDSCs. Mechanistically, sorafenib significantly inhibited the differentiation of macrophages by upregulating PPARα expression and suppressing the PU.1-CSF1R pathway.

CONCLUSION

Overall, our study demonstrated that sorafenib enhanced the function of MDSCs by facilitating PPARα-mediated FAO and further augmenting sorafenib resistance, which sheds light on dietary management and improves the therapeutic response in HCC.

S100P is a ferroptosis suppressor to facilitate hepatocellular carcinoma development by rewiring lipid metabolism

Ferroptosis is a newly identified programmed cell death induced by iron-driven lipid peroxidation and implicated as a potential approach for tumor treatment. However, emerging evidence indicates that hepatocellular carcinoma (HCC) cells are generally resistant to ferroptosis and the underlying molecular mechanism is poorly understood. Here, our study confirms that S100 calcium binding protein P (S100P), which is significantly up-regulated in ferroptosis-resistant HCC cells, efficiently inhibits ferroptosis. Mechanistically, S100P facilitates lysosomal degradation of acetyl-CoA carboxylase alpha (ACC1), which is indispensable for de novo biosynthesis of lipids. Loss of S100P elevates the expression of ACC1 and promotes ferroptotic sensitivity of HCC cells. S100P-mediated ACC1 degradation relies on RAB5C, which directs ACC1 to lysosome via P62-dependent selective autophagy. Knockdown of RAB5C or P62 abrogates S100P-induced lysosomal degradation of ACC1 and restores resistance of HCC cells to ferroptosis. Our work reveals an alternative anti-ferroptosis pathway and suggests S100P as a promising druggable target for ferroptosis-related therapy of HCC.

Sodium aescinate-induced hepatotoxicity via ATF4/GSH/GPX4 axis-mediated ferroptosis

Sodium aescinate (SA), a natural plant extract with various bioactivities, is widely used to treat oedema and inflammation in clinics. However, adverse events, including liver injury, kidney injury, and phlebitis, have been reported in patients with SA in recent years. In this study, we used BALB/c mice and L02 cells to evaluate the role of ferroptosis in SA-induced liver injury. SA significantly increased AST, ALT, MDA and Fe2+, decreased GSH levels, and induced pathological changes in the liver in vivo. SA also reduced the viability of L02 cells and induced LDH release, intracellular cysteine reduction, GSH depletion, iron accumulation, ROS production, and lipid peroxidation, indicating that SA causes ferroptosis. In addition, SA inhibited transcriptional activity of activating transcription factor 4 (ATF4) and subsequently reduced the expression of the downstream genes xCT (solute carrier family 7a member 11, SLC7A11) and Cystathionine gamma-lyase (CTH) which play vital roles in GSH biosynthesis. Interestingly, the cytotoxic effects of SA were effectively attenuated by ATF4 overexpression, while they were significantly aggravated by ATF4 silencing. These results revealed that SA triggers hepatocyte ferroptosis by inhibiting the activity of ATF4, which causes an oxidative imbalance.

Deciphering the role of the MALT1-RC3H1 axis in regulating GPX4 protein stability

Ferroptosis, a unique form of iron-dependent cell death triggered by lipid peroxidation accumulation, holds great promise for cancer therapy. Despite the crucial role of GPX4 in regulating ferroptosis, our understanding of GPX4 protein regulation remains limited. Through FACS-based genome-wide CRISPR screening, we identified MALT1 as a regulator of GPX4 protein. Inhibition of MALT1 expression enhances GPX4 ubiquitination-mediated degradation by up-regulating the E3 ubiquitin ligase RC3H1. Using both rescue assays and functional genetic screening, we demonstrate that pharmacologically targeting MALT1 triggers ferroptosis in liver cancer cells. Moreover, we show that targeting MALT1 synergizes with sorafenib or regorafenib to induce ferroptosis across multiple cancer types. These findings elucidate the modulatory effects of the MALT1-RC3H1 axis on GPX4 stability, revealing a molecular mechanism that could be exploited to induce ferroptosis for cancer therapy.

An Overview of Research Advances in Oncology Regarding the Transcription Factor ATF4

This review provides a comprehensive overview of the recent advancements in research on ATF4 (Activating Transcription Factor 4) within the field of oncology. As a crucial transcription factor, ATF4 has garnered increasing attention for its role in cancer research. The review begins with an exploration of the regulatory mechanisms of ATF4, including its transcriptional control, post-translational modifications, and interactions with other transcription factors. It then highlights key research findings on ATF4's involvement in various aspects of tumor biology, such as cell proliferation, differentiation, apoptosis and survival, invasion and metastasis, and the tumor microenvironment. Furthermore, the review discusses the potential of targeting ATF4 as a novel therapeutic strategy for cancer treatment. It also explores how ATF4's interactions with existing anticancer drugs could inform the development of more effective therapeutic agents. By elucidating the role of ATF4 in tumor biology and its potential clinical applications, this review aims to provide new insights and strategies for cancer treatment.

Role of disulfide death in cancer (Review)

The research field of regulated cell death is growing extensively. Following the recognition of ferroptosis, other unique and distinct forms of regulated cell death, including cuproptosis and disulfide death, have been identified. Disulfide death occurs due to the abnormal accumulation of disulfides within cells in environments lacking glucose, leading to contraction of the actin cytoskeleton, which ultimately triggers various signaling pathways and cell death. The induction of disulfide death in the treatment of cancer may exhibit significant therapeutic potential. Therefore, in the present review, a comprehensive and critical analysis of the current understanding of the molecular mechanisms and regulatory networks of disulfide death is presented. In addition, the potential physiological functions of disulfide death in tumor suppression and immune surveillance as well as its pathological roles and therapeutic potential are described. The core focus areas for future research into this form of cell death are also explored. Given the current lack of extensive clinical findings and well-defined key concepts, these may be regarded as pivotal points of interest in future studies.

Mechanisms and therapeutic potential of disulphidptosis in cancer

SLC7A11 plays a pivotal role in tumour development by facilitating cystine import to enhance glutathione synthesis and counteract oxidative stress. Disulphidptosis, an emerging form of cell death observed in cells with high expression of SLC7A11 under glucose deprivation, is regulated through reduction-oxidation reactions and disulphide bond formation. This process leads to contraction and collapse of the F-actin cytoskeleton from the plasma membrane, ultimately resulting in cellular demise. Compared to other forms of cell death, disulphidptosis exhibits distinctive characteristics and regulatory mechanisms. This mechanism provides novel insights and innovative strategies for cancer treatment while also inspiring potential therapeutic approaches for other diseases. Our review focuses on elucidating the molecular mechanism underlying disulphidptosis and its connection with the actin cytoskeleton, identifying alternative metabolic forms of cell death, as well as offering insights into disulphidptosis-based cancer therapy. A comprehensive understanding of disulphidptosis will contribute to our knowledge about fundamental cellular homeostasis and facilitate the development of groundbreaking therapies for disease treatment.

5-methylcytosine methylation of MALAT1 promotes resistance to sorafenib in hepatocellular carcinoma through ELAVL1/SLC7A11-mediated ferroptosis

Emerging evidence demonstrates that long non-coding RNAs (lncRNAs) play a crucial role in sorafenib resistance in hepatocellular carcinoma (HCC), and lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a dysregulated lncRNA in sorafenib-resistant HCC cells. However, the underlying regulatory mechanisms of MALAT1 in sorafenib-resistant HCC cells remain unclear. In the present study, we demonstrated that 5-methylcytosine (m5C) methylation catalyzed by NSUN2 and ALYREF contributed to the RNA stability and upregulation of MALAT1. The NSUN2/ALYREF/MALAT1 signaling axis was activated in sorafenib-resistant cells, and the upregulation of MALAT1 inhibited sorafenib-induced ferroptosis to drive sorafenib resistance. Mechanistically, MALAT1 maintained the mRNA stability of SLC7A11 by directly binding to ELAVL1 and stimulating its cytoplasmic translocation. Furthermore, we explored a new synergetic strategy for the treatment of HCC by combining MALAT1 inhibitor MALAT1-IN1 with sorafenib. The results demonstrated that MALAT1-IN1 significantly enhanced sorafenib efficacy for the treatment of HCC both in vitro and in vivo. Collectively, our work brings new insights into the epigenetic mechanisms of sorafenib resistance and offers an alternative therapeutic strategy targeting ferroptosis for sorafenib-resistant HCC patients.

Sorafenib, a Tyrosine Kinase Inhibitor, Synergistically Enhances the Ferroptosis Effects of Asiatic Acid in Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) remains one of the most common cancers worldwide. Asiatic acid (AA) is a natural triterpene, which is recognized as effect of antioxidant and antitumor. Sorafenib (Sor), an orally target drug, has been applicate for the HCC therapy. However, the synergistic effect of AA and Sor on human HCC is still unclear. Here, we explore the effect of combined treatment with AA and Sor in the HCC cell line SK-HEP-1 and HepG2. Compared with treating alone, our results demonstrated that AA combined with Sor synergistically inhibited proliferative rates in MTT assay and colony formation assay. We also found that AA combined with Sor in HCC cells strongly caused cell cycle arrest in G0/G1 phase and affected the protein level of cyclin D1 and SKP2. Furthermore, combination treatment strongly enhanced ferroptosis through cellular accumulation of iron ions, lipid peroxidation, and ferroptosis-related proteins (GPX4 and FTH1) in HCC cells. In addition, the combined treatment resulted in higher phosphorylation of JNK1/2 in the promotion of ferroptosis than drug treatment alone. These results indicate that AA combined with Sor synergistically improved ferroptosis in HCC cells through the regulation of JNK1/2 signaling. Taken together, the combinatorial strategy may serve as the potential treatment in HCC.

Ferroptosis, a therapeutic target for cardiovascular diseases, neurodegenerative diseases and cancer

The identification of ferroptosis represents a pivotal advancement in the field of cell death research, revealing an entirely novel mechanism of cellular demise and offering new insights into the initiation, progression, and therapeutic management of various diseases. Ferroptosis is predominantly induced by intracellular iron accumulation, lipid peroxidation, or impairments in the antioxidant defense system, culminating in membrane rupture and consequent cell death. Studies have associated ferroptosis with a wide range of diseases, and by enhancing our comprehension of its underlying mechanisms, we can formulate innovative therapeutic strategies, thereby providing renewed hope for patients.

Roles and Mechanisms of Ferroptosis in Sorafenib Resistance for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most prevalent malignant tumor, characterized by a poor prognosis. In recent decades, both the incidence and mortality rates of HCC have risen sharply. Sorafenib has emerged as the first conventional drug approved by the US Food and Drug Administration for first-line treatment in advanced HCC patients due to its favorable safety profile. However, its effectiveness is severely hindered by acquired drug resistance, which leads to only approximately 30% of HCC patients benefited from sorafenib therapy. Sorafenib resistance involves various mechanisms that inhibit cellular uptake of iron and reactive oxygen species (ROS). Consequently, ferroptosis a novel form of cell death contingent upon the accumulation of intracellular iron and ROS plays a critical role in mediating sorafenib resistance through the Hippo YAP pathway or Keap1-Nrf2 system. This review aimed to comprehensively elucidate the mechanisms underlying sorafenib resistance in HCC, particularly focusing on ferroptosis and its pathways, to provide valuable insights into targeting ferroptosis or its pathways for sorafenib-resistant HCC treatment.

Solanum torvum induces ferroptosis to suppress hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

Solanum torvum Sw. (ST) is used to clear heat toxins, promote blood circulation, and alleviate blood stasis. Therefore, this plant has traditionally been used as an ethnomedicine for common cold, chronic gastritis, and tumors.

AIM OF THE STUDY

This study aimed to elucidate the mechanism by which ST induces ferroptosis in hepatocellular carcinoma (HCC), the combination effect with lenvatinib, and the impact on lenvatinib-resistant cells.

MATERIALS AND METHODS

Cell viability assays were performed using different hepatoma cell lines treated with ST. Lipid peroxidation and iron assays were performed using flow cytometry. Molecules involved in the ferroptosis pathway were detected by Western blotting. Finally, a lenvatinib-resistant cell line was established to evaluate the antiproliferative effects of ST.

RESULTS

ST ethanol extract inhibited the growth of various hepatoma cell lines. A significant reduction in glutathione peroxidase 4 (GPX4) expression was observed following ST treatment, which was accompanied by increased lipid peroxidation and Fe2+ accumulation. ST induced ferroptosis mainly through heme oxygenase-1 (HO-1) expression. HO-1 knockdown reduced ST-induced lipid peroxidation and reversed GPX4 suppression. Acyl-CoA synthetase long-chain family member 4 (ACSL4) also participated in ST-induced ferroptosis. ST and lenvatinib combination showed an additive effect, and ST retained its potential anti-HCC efficacy in a lenvatinib-resistant cell line.

CONCLUSION

This study demonstrated that the ethanol extract of ST inhibits hepatoma cell growth by inducing ferroptosis. ST displayed an additive effect with lenvatinib in Hep 3B cells and showed remarkable anti-HCC activity in lenvatinib-resistant Hep 3B cells. Collectively, the study shows that ST might have the potential to reduce lenvatinib use in clinical practice and salvage cases of lenvatinib resistance.

Autophagy-based therapy for hepatocellular carcinoma: from standard treatments to combination therapy, oncolytic virotherapy, and targeted nanomedicines

Human hepatocellular carcinoma (HCC) has been identified as a significant cause of mortality worldwide. In recent years, extensive research has been conducted to understand the underlying mechanisms of autophagy in the pathogenesis of the disease, with the aim of developing novel therapeutic agents. Targeting autophagy with conventional therapies in invasive HCC has opened up new opportunities for treatment. However, the emergence of resistance and the immunosuppressive tumor environment highlight the need for combination therapy or specific targeting, as well as an efficient drug delivery system to ensure targeted tumor areas receive sufficient doses without affecting normal cells or tissues. In this review, we discuss the findings of several studies that have explored autophagy as a potential therapeutic approach in HCC. We also outline the potential and limitations of standard therapies for autophagy modulation in HCC treatment. Additionally, we discuss how different combination therapies, nano-targeted strategies, and oncolytic virotherapy could enhance autophagy-based HCC treatment in future research.

Linking homocysteine and ferroptosis in cardiovascular disease: insights and implications

Homocysteine (Hcy) is a metabolic intermediate product derived from methionine. Hyperhomocysteinemia is a condition associated with various diseases. Hcy is recognized as a risk factor for cardiovascular disease (CVD). Ferroptosis, a novel form of cell death, is primarily characterized by substantial iron accumulation and lipid peroxidation. Recent research indicates a close association between ferroptosis and the pathophysiological processes of tumors, neurological diseases, CVD, and other ailments. However, limited research has been conducted on the impact of Hcy on ferroptosis. Therefore, this paper aimed to investigate the potential roles and mechanisms of homocysteine and ferroptosis in the context of cardiovascular disease. By conducting comprehensive literature research and analysis, we aimed to summarize recent advancements in understanding the effects of homocysteine on ferroptosis in cardiovascular diseases. This research contributes to a profound understanding of this critical domain.

Babaodan overcomes cisplatin resistance in cholangiocarcinoma via inhibiting YAP1

CONTEXT

Cholangiocarcinoma with highly heterogeneous, aggressive, and multidrug resistance has a poor prognosis. Although babaodan (BBD) combined with cisplatin improved non-small cell lung cancer efficacy, its impact on overcoming resistance in cholangiocarcinoma remains unexplored.

OBJECTIVE

This study explored the role and mechanism of BBD on cisplatin resistance in cholangiocarcinoma cells (CCAs).

MATERIALS AND METHODS

Cisplatin-resistant CCAs were exposed to varying concentrations of cisplatin (25-400 μg/mL) or BBD (0.25-1.00 mg/mL) for 48 h. IC50 values, inhibition ratios, apoptosis levels, DNA damage, glutathione (GSH) levels, oxidized forms of GSH, total GSH content, and glutaminase relative activity were evaluated using the cell counting kit 8, flow cytometry, comet assay, and relevant assay kits.

RESULTS

BBD-reduced the cisplatin IC50 in CCAs from 118.8 to 61.83 μg/mL, leading to increased inhibition rate, apoptosis, and DNA damage, and decreased expression of B-cell lymphoma-2, p-Yes-associated protein 1/Yes-associated protein 1, solute carrier family 1 member 5, activating transcription factor 4, and ERCC excision repair 1 in a dose-dependent manner with maximum reductions of 78.97%, 51.98%, 54.03%, 56.59%, and 63.22%, respectively; bcl2-associated X and gamma histone levels were increased by 0.43-115.77% and 22.15-53.39%. The impact of YAP1 knockdown on cisplatin-resistant CCAs resembled BBD. GSH, oxidized GSH species, total GSH content, and glutaminase activity in cisplatin-resistant CCAs with BBD treatment also decreased, while YAP1 overexpression countered BBD's effects.

DISCUSSION AND CONCLUSION

This study provides a scientific basis for BBD clinical application and provides a new direction for BBD biological mechanism research.

The Integrated Stress Response in Pancreatic Development, Tissue Homeostasis, and Cancer

Present in all eukaryotic cells, the integrated stress response (ISR) is a highly coordinated signaling network that controls cellular behavior, metabolism, and survival in response to diverse stresses. The ISR is initiated when any 1 of 4 stress-sensing kinases (protein kinase R-like endoplasmic reticulum kinase [PERK], general control non-derepressible 2 [GCN2], double-stranded RNA-dependent protein kinase [PKR], heme-regulated eukaryotic translation initiation factor 2α kinase [HRI]) becomes activated to phosphorylate the protein translation initiation factor eukaryotic translation initiation factor 2α (eIF2α), shifting gene expression toward a comprehensive rewiring of cellular machinery to promote adaptation. Although the ISR has been shown to play an important role in the homeostasis of multiple tissues, evidence suggests that it is particularly crucial for the development and ongoing health of the pancreas. Among the most synthetically dynamic tissues in the body, the exocrine and endocrine pancreas relies heavily on the ISR to rapidly adjust cell function to meet the metabolic demands of the organism. The hardwiring of the ISR into normal pancreatic functions and adaptation to stress may explain why it is a commonly used pro-oncogenic and therapy-resistance mechanism in pancreatic ductal adenocarcinoma and pancreatic neuroendocrine tumors. Here, we review what is known about the key roles that the ISR plays in the development, homeostasis, and neoplasia of the pancreas.

The Hippo Coactivator TAZ Exacerbates Cisplatin-Induced Acute Renal Injury

Introduction

Transcriptional coactivator with PDZ-binding motif (TAZ), a Hippo signaling pathway effector, maintains the balance of cell proliferation, differentiation, and death. However, the role of TAZ in tubular cell survival and acute kidney injury (AKI) remains largely unknown.

Methods

We used the RNA-seq database, Western blot, and immunohistochemistry to examine TAZ expression in kidneys from cisplatin-induced AKI. We generated tubular-specific TAZ knockout mice to assess the role of TAZ in cisplatin-induced renal toxicity. Immunoprecipitation-mass spectrometry followed standard procedures.

Results

TAZ was activated in tubular cells in kidneys injected with cisplatin. Conditional deletion of TAZ in tubular cells confers ferroptosis resistance and protects kidneys from cisplatin-induced AKI, whereas overexpression of TAZ(S89A) exacerbates cisplatin-induced ferroptosis. Inhibition of ferroptosis with ferrostatin-1 potently preserves renal function and alleviates morphological injury and tubular cell ferroptosis induced by cisplatin. Mechanistically, in a PPARδ-dependent manner, but not TEAD, TAZ reduces the expression of glutathione peroxidase 4 (GPX4), thus exacerbating cisplatin-induced ferroptosis.

Conclusions

Our findings show that cisplatin-induced AKI and tubular cell ferroptosis are mediated by TAZ-PPARδ interaction through regulation of GPX4, highlighting TAZ as a potential therapeutic candidate for AKI.

Corosolic acid inhibits EMT in lung cancer cells by promoting YAP-mediated ferroptosis

BACKGROUND

Corosolic acid (CA), a naturally occurring pentacyclic triterpenoid is renowned for its anticancer attributes. Previous studies have predominantly centered on the anticancer properties of CA in lung cancer, specifically its role in inducing apoptosis, however, investigations regarding its involvement in ferroptosis have been scarce.

METHODS

The apoptotic and proliferative effects were evaluated by CCK8 and colony formation assay. Cell death and ROS generation were measured to assess the response of CA to iron death induction. Scratch and invasion assays were performed to verify the effect of CA on the invasive ability of lung cancer cells. Protein and mRNA expression were analyzed using Western blotting and qPCR. The CHX assay was carried out to detect protein half-life. Metabolite levels were measured with appropriate kits. Protein expression was detected through IF and IHC. A xenograft tumor model was established to investigate the inhibitory effect of CA on lung cancer in vivo.

RESULTS

The current findings revealed that CA exerts its anticancer effect by inducing cell death, accompanied by the accumulation of lipid reactive oxygen species (ROS), hinting at the possible involvement of ferroptosis. Our experimental results further substantiated the significance of ferroptosis in the CA anticancer mechanism, as ferroptosis inhibitors were found to effectively rescue CA-induced cell death. Significantly, we demonstrated for the first time that CA could induce ferroptosis further by suppressing EMT in lung cancer cells. Additionally, CA could regulate GPX4 to induce ferroptosis, interestingly, CA downregulated GSH synthetase by inhibiting YAP rather than GPX4, thereby reducing GSH, inducing ferroptosis, and further suppressing EMT in lung cancer cells.We also discovered that GSS is a crucial downstream target of YAP in regulating GSH. Moreover, a xenograft mouse model indicated that CA could trigger ferroptosis in lung cancer cells by regulating YAP expression and GSH levels.

CONCLUSION

CA inhibited lung cancer cell metastasis by inducing ferroptosis. Our data offer the first evidence that CA induces ferroptosis in lung cancer cells by regulating YAP/GSS to modulate GSH, thereby further suppressing EMT. These results imply the potential of CA as an inducer of ferroptosis to inhibit lung cancer metastasis.

Brusatol improves the efficacy of sorafenib in Huh7 cells via ferroptosis resistance dependent Nrf2 signaling pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is a common malignancy with a poor prognosis. The recommended treatment of unresectable HCC involves targeted therapy, for example sorafenib, combined with immunotherapy. A recent article reported that sorafenib could induce ferroptosis escape in HCC. Brusatol is a novel Nrf2 inhibitor that takes effects in various diseases. In our study, we aimed to identify whether the addition of Brusatol to sorafenib could reverse ferroptosis escape in Huh7 cells.

METHODS

The cultured Huh7 cells treated by sorafenib with or without Brusatol addition were harvested for ferroptotic phenotype experiments and ferroptosis-related markers such as GPX4 and SLC7A11 were detected. In vivo experiments were conducted to discover the effect of Brusatol in combination with sorafenib in liver tumor bearing mice. Mechanism signaling pathways were detected by RNA-sequencing.

RESULTS

Brusatol alone could induce Huh7 cell death and sorafenib could moderately mediate Huh7 cell ferroptosis by paradoxically inhibiting GPX4. However, sorafenib simultaneously upregulates Nrf2 signaling in Huh7 cells fighting against ferroptosis to result in sorafenib resistance. The addition of Brusatol could potentiate ferroptosis in Huh7 cells through downregulating Nrf2 and the downstream HO-1 and NQO1, thus enhancing the efficacy of sorafenib, which could be reversed by ferrostatin-1 treatment.

CONCLUSION

In conclusion, Brusatol improves the efficacy of sorafenib by inducing ferroptosis via hindering Nrf2 signaling activation in HCC.

Ferroptosis: insight into the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignances in the world, with high morbidity and mortality. Due to the hidden onset of symptoms, there are huge obstacles in early diagnosis, recurrence, metastasis and drug resistance. Although great strides have been made in the treatment of HCC, effective treatment options are still limited and achieving longer survival for patients remains urgent. Ferroptosis is a novel type of programmed cell death that is mainly caused by iron-dependent oxidative damage. With further investigations, ferroptosis has been proved to be associated with the occurrence and development of various tumors. This article reviews the regulatory mechanism and signal transduction pathways of ferroptosis, investigates the complex relationship between autophagy, sorafenib resistance and immunotherapy with ferroptosis involved in HCC, providing new ideas and directions for the treatment of HCC.

Comprehensive review and updated analysis of DNA methylation in hepatocellular carcinoma: From basic research to clinical application

Hepatocellular carcinoma (HCC) is a primary malignant tumour, ranking second in global mortality rates and posing significant health threats. Epigenetic alterations, particularly DNA methylation, have emerged as pivotal factors associated with HCC diagnosis, therapy, prognosis and malignant progression. However, a comprehensive analysis of the DNA methylation mechanism driving HCC progression and its potential as a therapeutic biomarker remains lacking. This review attempts to comprehensively summarise various aspects of DNA methylation, such as its mechanism, detection methods and biomarkers aiding in HCC diagnosis, treatment and prognostic assessment of HCC. It also explores the role of DNA methylation in regulating HCC's malignant progression and sorafenib resistance, alongside elaborating the therapeutic effects of DNA methyltransferase inhibitors on HCC. A detailed examination of these aspects underscores the significant research on DNA methylation in tumour cells to elucidate malignant progression mechanisms, identify diagnostic markers and develop new tumour-specific inhibitors for HCC. KEY POINTS: A comprehensive summary of various aspects of DNA methylation, such as its mechanism, detection methods and biomarkers aiding in diagnosis and treatment. The role of DNA methylation in regulating hepatocellular carcinoma's (HCC) malignant progression and sorafenib resistance, alongside elaborating therapeutic effects of DNA methyltransferase inhibitors. Deep research on DNA methylation is critical for discovering novel tumour-specific inhibitors for HCC.

The role of metal ions in stroke: Current evidence and future perspectives

Metal ions play a pivotal role in maintaining optimal brain function within the human body. Nevertheless, the accumulation of these ions can result in irregularities that lead to brain damage and dysfunction. Disruptions of metal ion homeostasis can result in various pathologies, including inflammation, redox dysregulation, and blood-brain barrier disruption. While research on metal ions has chiefly focused on neurodegenerative diseases, little attention has been given to their involvement in the onset and progression of stroke. Recent studies have identified cuproptosis and confirmed ferroptosis as significant factors in stroke pathology, underscoring the importance of metal ions in stroke pathology, including abnormal ion transport, neurotoxicity, blood-brain barrier damage, and cell death. Additionally, it provides an overview of contemporary metal ion chelators and detection techniques, which may offer novel approaches to stroke treatment.

crVDAC3 alleviates ferroptosis by impeding HSPB1 ubiquitination and confers trastuzumab deruxtecan resistance in HER2-low breast cancer

AIMS

With the wide application of trastuzumab deruxtecan (T-DXd), the survival of HER2-low breast cancer patients is dramatically improved. However, resistance to T-DXd still exists in a subset of patients, and the molecular mechanism remains unclear.

METHODS

An in vivo shRNA lentiviral library functional screening was performed to identify potential circular RNA (crRNA) that mediates T-DXd resistance. RNA pull-down, mass spectrometry, RNA immunoprecipitation, and co-immunoprecipitation assays were conducted to investigate the molecular mechanism. Ferroptosis was detected using C11-BODIPY, Liperfluo, FerroOrange staining, glutathione quantification, malondialdehyde quantification, and transmission electron microscopy. Molecular docking, virtual screening, and patient-derived xenograft (PDX) models were used to validate therapeutic agents.

RESULTS

VDAC3-derived crRNA (crVDAC3) ranked first in functional shRNA library screening. Knockdown of crVDAC3 increased the sensitivity of HER2-low breast cancer cells to T-DXd treatment. Further mechanistic research revealed that crVDAC3 specifically binds to HSPB1 protein and inhibits its ubiquitination degradation, leading to intracellular accumulation and increased levels of HSPB1 protein. Notably, suppression of crVDAC3 dramatically increases excessive ROS levels and labile iron pool accumulation. Inhibition of crVDAC3 induces ferroptosis in breast cancer cells by reducing HSPB1 expression, thereby mediating T-DXd resistance. Through virtual screening and experimental validation, we identified that paritaprevir could effectively bind to crVDAC3 and prevent its interaction with HSPB1 protein, thereby increasing ubiquitination degradation of HSPB1 protein to overcome T-DXd resistance. Finally, we validated the enhanced therapeutic efficacy of T-DXd by paritaprevir in a HER2-low PDX model.

CONCLUSION

This finding reveals the molecular mechanisms underlying T-DXd resistance in HER2-low breast cancer. Our study provides a new strategy to overcome T-DXd resistance by inhibiting the interaction between crVDAC3 and HSPB1 protein.

Advances in the study of the mechanism of action of miR‑22 in liver lesions (Review)

Globally, nearly 2 million deaths annually are attributed to the development of liver diseases, with liver cancer and cirrhosis being particularly prominent, which makes liver disease a significant global health concern. Cirrhosis is closely linked to the evolution of hepatitis, hepatic fibrosis and fatty liver. However, most liver diseases have an insidious onset, are challenging to treat and the prognosis and efficacy of current therapies are unsatisfactory, which can result in irreversible functional damage to the liver. Therefore, there is an urgent need to explore the molecular mechanisms underlying liver disease and identify new biomarkers and therapeutic targets. In previous years, microRNAs (miRs), a class of short non-coding RNAs comprising 17-25 nucleotides, have attracted attention for their roles in various types of liver diseases. Among them, miR-22 serves a unique role in mediating multiple pathway mechanisms and epigenetic modifications and can act both as an inhibitor of liver cancer and a metabolic blocker. Given its close association with the liver, several studies have reported that the differential expression of miR-22 regulates the metabolic process of liver cancer and is involved in the evolution of hepatic fibrosis and steatohepatitis, making it a potential target for early diagnosis and treatment. The present manuscript aimed to comprehensively review the key role of miR-22 in the evolution of liver diseases and offer valuable references and guidance for subsequent studies by identifying its specific mechanism of action and future development prospects.

Ferroptosis-related gene signature for predicting prognosis and identifying potential therapeutic drug in EGFR wild-type lung adenocarcinoma

Epidermal growth factor receptor wild type lung adenocarcinoma (EGFRWT LUAD) still has limited treatment options and unsatisfactory clinical outcomes. Ferroptosis, as a form of cell death, has been reported to play a dual role in regulating tumor cell survival. In this study, we constructed a 3-ferroptosis-gene signature, FeSig, and verified its accuracy and efficacy in predicting EGFRWT LUAD prognosis at both the RNA and protein levels. Patients with higher FeSig scores were found to have worse clinical outcomes. Additionally, we explored the relationship between FeSig and tumor microenvironment, revealing that enhanced interactions between fibroblasts and tumor cells in FeSighigh patients causing tumor resistance to ferroptosis. To address this challenge, we screened potential drugs from NCI-60 (The US National Cancer Institute 60 human tumour cell line anticancer drug screen) and Connectivity map database, ultimately identifying 6-mercatopurine (6-MP) as a promising candidate. Both in vitro and in vivo experiments demonstrated its efficacy in treating FeSighigh EGFRWT LUAD tumor models. In summary, we develop a novel FeSig for predicting prognosis and guiding drug application.

Progress in research of ferroptosis in gastrointestinal tumors

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

Spliceosomal GTPase Eftud2 deficiency-triggered ferroptosis leads to Purkinje cell degeneration

Spliceosomal GTPase elongation factor Tu GTP binding domain containing 2 (EFTUD2) is a causative gene for mandibulofacial dysostosis with microcephaly (MFDM) syndrome comprising cerebellar hypoplasia and motor dysfunction. How EFTUD2 deficiency contributes to these symptoms remains elusive. Here, we demonstrate that specific ablation of Eftud2 in cerebellar Purkinje cells (PCs) in mice results in severe ferroptosis, PC degeneration, dyskinesia, and cerebellar atrophy, which recapitulates phenotypes observed in patients with MFDM. Mechanistically, Eftud2 promotes Scd1 and Gch1 expression, upregulates monounsaturated fatty acid phospholipids, and enhances antioxidant activity, thereby suppressing PC ferroptosis. Importantly, we identified transcription factor Atf4 as a downstream target to regulate anti-ferroptosis effects in PCs in a p53-independent manner. Inhibiting ferroptosis efficiently rescued cerebellar deficits in Eftud2 cKO mice. Our data reveal an important role of Eftud2 in maintaining PC survival, showing that pharmacologically or genetically inhibiting ferroptosis may be a promising therapeutic strategy for EFTUD2 deficiency-induced disorders.

Overexpression of ATF4 Inhibits Ferroptosis to Alleviate Anxiety Disorders by Activating the TGF-β Signaling Pathway

Background

Anxiety disorders seriously impair patients' mental health and quality of life, with limited effectiveness of current treatments. Dysregulation of activating transcription factor 4 (ATF4) is involved in various mental diseases, but the research on its potential roles in alleviating anxiety disorders remains limited.

Methods

ATF4 was screened out by bioinformatic analysis and its expression was verified in vivo. Mice were treated with 21 d of chronic restraint stress to establish the anxiety mice model. The anxiolytic effect of ATF4 was assessed by a battery of behavior tests and evaluation of hippocampal tissue damage after overexpressing ATF4. Ferroptosis-related indicators were detected by enzyme-linked immunosorbent assay and Western blotting. Then the transforming growth factor beta (TGF-β) signaling pathway was predicted as the downstream regulatory pathway of ATF4 by bioinformatic methods. Western blotting was conducted to detect the protein expression level of TGF-β1, small mothers against decapentaplegic 3 (Smad3), and phospho-Smad3 (p-Smad3).

Results

ATF4 was screened out as a ferroptosis-related anxiolytic gene after bioinformatics analysis and was down-regulated in the anxiety mice model. Mice with ATF4 overexpression spent more time in the open arms in the elevated plus-maze test, appeared more frequently in the central area in the open-field test, and decreased the immobility time in the forced swimming and tail suspension tests. Hippocampal tissue damage was alleviated, ferroptosis was suppressed, and the levels of TGF-β1 and p-Smad3/Smad3 were increased by AFT4 overexpression.

Conclusion

ATF4 overexpression can repress ferroptosis to improve anxiety disorders by activating the TGF-β signaling pathway.