ACSL3 and ACSL4, Distinct Roles in Ferroptosis and Cancers

Reactive oxygen species-sensitive fenofibrate-loaded dextran nanoparticles in alleviation of osteoarthritis

Osteoarthritis (OA) stands as a prevalent chronic joint pathology, emerging as a leading cause of disability on a global scale. However, the current therapeutic efficacy in OA treatment remains unsatisfactory. Chondrocyte ferroptosis has become to a critical target for OA treatment, while the fabrication of nanomedicines emerges as a promising strategy for OA treatment. Nevertheless, there exists a paucity of reported nanomedicine systems designed to combat chondrocyte ferroptosis for OA alleviation. In light of this, our study introduced a reactive oxygen species (ROS)-sensitive fenofibrate-loaded targeted nanoparticle (FN-CNPs) as a means of alleviating OA by suppressing chondrocyte ferroptosis. In vitro investigations demonstrated the FN-CNPs can achieve this through the reduction of lipid peroxidation and ROS levels, as well as the elevation of anti-ferroptosis markers (GPX4, FSP1, and ACSL3). Consequently, FN-CNPs exhibited significant anti-inflammatory effects and downregulated the expression of key catabolic mediators in vitro. Furthermore, in vivo studies underscored the ability of FN-CNPs to alleviate OA progression and protect cartilage. Collectively, these findings highlight the efficacy of FN-CNPs in mitigating OA progression by suppressing chondrocyte ferroptosis via regulating ROS levels, antioxidant systems and lipid metabolism of chondrocytes.

The m6A modification of ACSL4 mRNA sensitized esophageal squamous cell carcinoma to irradiation via accelerating ferroptosis

Radioresistance is a major obstacle for the therapy of esophageal squamous cell carcinoma (ESCC) and lead to a poor prognosis. Ferroptosis is supposed to be responsible for radioresistance. However, the ferroptosis-induced radioresistance in ESCC and its related regulatory mechanisms are not yet fully understood. In this study, human ESCC cell line and the corresponding radioresistance cells were irradiated with 6 megavolts (MV) X-ray. It was showed that irradiation led to less ferroptosis in radioresistant ESCC cells as compared to the parental cells, as depicted by transmission electron microscopy, intracellular Fe2+ iron contents, lipid peroxidation, and expression of COX2. The increase of ASCL4 expression levels in radioresistant cells after radiotherapy was smaller than that in the parental cells. ACSL4 overexpression significantly enhanced ferroptosis. The fold increase in ACSL4 m6A modification in the radioresistant cells was significantly smaller than that in the parental cells as detected by methylated RNA immunoprecipitation with qRT-PCR. METTL14 overexpression accelerated ferroptosis induced by irradiation via upregulating m6A modification of ACSL4 mRNA. In conclusions, ferroptosis ablation was responsible for the radioresistant of ESCC. The METTL14-mediated m6A modification of ACSL4 mRNA sensitized ESCC to irradiation via accelerating ferroptosis. This study sheds new light on our understanding of radioresistant in ESCC, and provides potential strategies for ESCC radiotherapy.

Celastrol alleviates secondary brain injury following intracerebral haemorrhage by inhibiting neuronal ferroptosis and blocking blood-brain barrier disruption

Background

Following recent research advancements, an increasing level of evidence had been published to indicate that celastrol exerted a therapeutic effect on a range of nervous system diseases. This study therefore aimed to investigate the potential involvement of celastrol on ferroptosis and the blood-brain barrier disruption in intracerebral haemorrhage.

Methods

We established a rat intracerebral haemorrhage and adrenal pheochromocytoma cell (PC12) OxyHb models using an ACSL4 overexpression vector. Ferroptosis-related indices were assessed using corresponding assay kits, and immunofluorescence and flow cytometry were used to measure reactive oxygen species (ROS) levels. Additionally, quantitative PCR (qPCR) and western blot analyses were conducted to evaluate the expression of key proteins and elucidate the role of celastrol in intracerebral haemorrhage (ICH).

Results

Celastrol significantly improved neurological function scores, blood-brain barrier integrity, and brain water content in rats with ICH. Moreover, subsequent analysis of ferroptosis-related markers, such as Fe2+, ROS, MDA, and SOD, suggested that celastrol exerted a protective effect against the oxidative damage induced by ferroptosis in ICH rats and cells. Furthermore, Western blotting indicated that celastrol attenuated ferroptosis by modulating the expression levels of key proteins, including acyl-CoA synthetase long-chain family member 4 (ACSL4), glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), and anti-transferrin receptor 1 (TFR1) both in vitro and in vivo. ACSL4 overexpression attenuated the neuroprotective effects of celastrol on ICH in vitro. Molecular docking analysis revealed that celastrol interacted with ACSL4 via the GLU107, GLN109, ASN111, and LYS357 binding sites.

Conclusions

Celastrol exerted antioxidant properties and aids in neurological recovery after stroke by suppressing ACSL4 expression during ferroptosis. As such, this drug represented a promising pharmaceutical candidate for the treatment of ICH.

Dapagliflozin alleviates high-fat-induced obesity cardiomyopathy by inhibiting ferroptosis

AIM

Dapagliflozin (Dapa) is a novel hypoglycaemic agent with multiple cardiovascular protective effects, and it is widely used in treatment of heart failure patients, but whether it can improve obese phenotype of heart failure and its mechanism is still unclear. Ferroptosis is an iron dependent form of cell death and has been proved to be an important role in heart failure. The aim of this study is to determine whether Dapa improves obesity-related heart failure by regulating ferroptosis in high-fat diet rats.

METHODS AND RESULTS

Male SD rats were fed a high-fat diet for 12 weeks and confirmed of obese heart failure by metabolic parameters and cardiac ultrasound. Being overweight by 20% compared with the normal group, with elevated systolic blood pressure and abnormal levels of insulin and blood lipid (TG and LDL-c), is recognized as obesity. The obese rats with reduced EF, FS, and E/A shown on ultrasound are defined as the obese heart failure (OHF) group. Histological tests confirmed the more pronounced cardiac fibrosis, mitochondrial volume and collagen deposition in OHF group. Dapa treatment effectively reduced body weight, INS, ISI/IRI index, TG and HDL-C levels (P < 0.05). Also, Dapa administration can slightly decrease the SBP and DBP levels; however, there was no statistical difference among those four groups. Furthermore, Dapa treatment can significantly improve high-fat induced systolic and diastolic dysfunction via regulating cardiac histological abnormalities, including less obvious mitochondrial swelling, muscle fibre dissolution and collagen deposition. Additionally, genes from the OHF group were used by GO enrichment analysis, and it shows that ferroptosis metabolic pathway participated in the development of obese phenotype of heart failure. More importantly, Dapa significantly inhibited Fe2+ and MDA levels (P < 0.05), but augmented GSH content (P < 0.05). In addition, the mRNAs and protein expression of some important regulators of ferroptosis, like GPX4, SLC7A11, FTH1 and FPN1, were all decreased after Dapa intervention.

CONCLUSION

Dapa improved high-fat induced obese cardiac dysfunction via regulating ferroptosis pathway.

YAP O-GlcNAcylation contributes to corneal epithelial cell ferroptosis under cigarette smoke exposure

Cigarette smoke (CS) is an important indoor air pollutant associated with an increased risk of ocular surface disease. As the eye's outermost layer, the cornea is highly sensitive to air pollutants like CS. However, the specific mechanisms linking CS exposure to corneal dysfunction have not been fully elucidated. In the present study, we found that CS exposure damages corneal epithelial cells, accompanied by increased iron (Fe2+) levels and lipid peroxidation, both hallmarks of ferroptosis. Ferroptosis inhibitors, including Ferrostatin-1 (Fer-1) and Deferoxamine mesylate (DFO), protect against CS-induced cell damage. To understand the underlying mechanisms, we investigated how CS affects iron and lipid metabolism. Our results showed that CS could upregulate intracellular iron levels by increasing TFRC expression and promote lipid peroxidation by increasing ACSL4 expression. Silencing ACSL4 or TFRC expression prevented CS-induced ferroptosis. Furthermore, we found that the upregulation of TFRC and ACSL4 was driven by increased YAP transcription. Pharmacological or genetic inhibition of YAP effectively prevented corneal epithelial cell ferroptosis under CS stimulation. Additionally, our results suggest that CS exposure could increase O-GlcNAc transferase activity, leading to YAP O-GlcNAcylation. This glycosylation of YAP interfered with its K48-linked ubiquitination, resulting in YAP stabilization. Collectively, we found that CS exposure induces corneal epithelial cell ferroptosis via the YAP O-GlcNAcylation, and provide evidence that CS exposure is a strong risk factor for ocular surface disease.

Sophora alopecuroide - Taraxacum decoction (STD) inhibits non-small cell lung cancer via inducing ferroptosis and modulating tumor immune microenvironment

The Sophora alopecuroide - Taraxacum Decoction (STD) is a traditional Chinese herbal formulation that has demonstrated significant potential in combating tumors. Despite its apparent effectiveness, the specific mechanisms through which STD exerts its anti-tumor properties remain largely unexplored and are yet to be fully understood. In our study, we provided evidence that STD effectively inhibits cellular growth and movement, as well as halting the cell cycle at the G2/M checkpoint. Furthermore, our pharmacological network analysis indicated that STD might induce cell death through a process known as ferroptosis. This hypothesis was substantiated by observing important biochemical changes associated with ferroptosis, including a decrease in glutathione (GSH) levels, an increase in iron accumulation, and elevated levels of reactive oxygen species (ROS) and lipid peroxidation. Additionally, we noted a significant rise in the expression of pro-ferroptosis genes such as Keap1, Nrf2, and HO-1, further supporting our findings. Significantly, and in line with the in vitro results, STD also showed a strong ability to inhibit tumor growth by inducing ferroptosis in a subcutaneous tumor model. Additionally, STD treatment changed the tumor immune microenvironment (TIME), as seen by an increase in CD107a+ CD8 and NK cells within the tumor. These findings demonstrate that STD induces ferroptosis and alters TIME to combat tumors, suggesting that STD may be a viable alternative treatment for patients with NSCLC.

Cigarette smoke extract induces ferroptosis in human retinal pigment epithelial cells

Background

Age-related macular degeneration (AMD) is a common blindness diseases. Retinal pigment epithelium (RPE) dysfunction due to smoking is an essential environmental factor in the pathogenesis of AMD. Ferroptosis is a novel type of iron-dependent programmed cell death (PCD). However, the relationship between cigarette smoke extract (CSE)-induced RPE damage and ferroptosis remains unclear.

Methods

In our study, we extracted CSE using a modified device to explore the optimal concentration of CSE, and observed the expression of proteins and molecules after CSE exposure for ARPE-19 cells by protein immunoblotting and assay kits for iron ions and mitochondrial membrane potential (MMP). At the same time, CSE was injected into the vitreous cavity of mice with a microsyringe for AMD modeling to observe the morphology of the retina-RPE-choroid complex and the differences expression of proteins. In addition, the protective effects of ferroptosis inhibitors on CSE-induced RPE cell damage were also investigated by in vivo and in vitro experiments.

Results

In this study, we observed that CSE induced cellular damage in a human retinal pigment epithelial cell line (ARPE-19), resulting in ferrous ion (Fe2+) accumulation, an increas in reactive oxygen species (ROS) and lipid peroxidation (LP), a reduction in GSH levels, and the inhibition of Gpx4 expression. In addition, transmission electron microscopy (TEM) of in vivo and in vitro samples showed that after exposure to CSE, the mitochondria of RPE cells were wrinkled, the membrane density was increased, and the number of cristae decreased or cristae were not observed.

Conclusions

The results of this study indicate that the ferroptosis inhibitors ferrostatin-1 (Fer-1) and liproxstatin-1 (Lip-1) protect RPE cells from CSE-induced ferroptosis, and this evidence paves the way for AMD studies.

Tao-Hong-Si-Wu-Tang improves thioacetamide-induced liver fibrosis by reversing ACSL4-mediated lipid accumulation and promoting mitophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Liver fibrosis is a generic fibrous scarring event resulting from accumulation of extracellular matrix (ECM) proteins, easily progressing to end-stage liver diseases. Tao-Hong-Si-Wu-Tang (THSWT) is a traditional Chinese medicine formula applied in clinics to treat gynecological and chronic liver diseases. However, the role of THSWT on thioacetamide (TAA)-induced hepatic fibrosis and the specific mechanisms remains unclear.

AIM OF THE STUDY

To investigate the improving effects of THSWT on TAA-insulted hepatic fibrosis and the underlying mechanisms.

MATERIALS AND METHODS

UHPLC-MS/MS was performed to explore the chemical characterization of THSWT. Mice were orally administered with THSWT once daily for 6 weeks along with TAA challenge. Liver function was reflected through serum biomarkers and histopathological staining. RNA sequencing, non-targeted metabolomics and molecular biology experiments were applied to investigate the underlying mechanisms.

RESULTS

THSWT profoundly repaired lipid metabolism dysfunction and blocked collagen accumulation both in TAA-stimulated mice and in hepatocytes. Results of RNA sequencing and non-targeted metabolomics revealed that the anti-fibrotic effects of THSWT mostly relied on lipid metabolism repairment by increasing levels of acetyl-CoA, phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine and lysophosphatidylethanolamine, and decreasing relative abundances of acyl-CoA, total cholesterol, diacylglycerol, triacylglycerol and phosphatidylinositol. Mechanically, long-chain acyl-CoA synthetases 4 (ACSL4) was a key profibrotic target both in human and mice by disrupting lipid oxidation and metabolism in hepatic mitochondria. THSWT effectively blocked ACSL4 and promoted mitophagy to reverse above outcomes, which was verified by mitophagy depletion.

CONCLUSION

THSWT may be a promising therapeutic option for treating hepatic fibrosis and its complications by modulating lipid metabolism and promoting mitophagy in livers.

Ferroptosis: a new promising target for hepatocellular carcinoma therapy

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

Hypoxia and ferroptosis

Ferroptosis is a novel, iron-dependent cell death characterized by the excessive accumulation of ferroptosis lipid peroxides ultimately leading to oxidative damage to the cell membrane. Iron, lipid, amino acid metabolism, and other signaling pathways all control ferroptosis. Numerous bodily tissues experience hypoxia under normal and pathological circumstances. Tissue cells can adjust to these changes by activating the hypoxia-inducible factor (HIF) signaling pathway and other mechanisms in response to the hypoxic environment. In recent years, there has been increasing evidence that hypoxia and ferroptosis are closely linked, and that hypoxia can regulate ferroptosis in specific cells and conditions through different pathways. In this paper, we review the possible positive and negative regulatory mechanisms of ferroptosis by hypoxia-inducible factors, as well as ferroptosis-associated ischemic diseases, with the intention of delivering novel therapeutic avenues for the defense and management of hypoxic illnesses linked to ferroptosis.

The Role of Ferroptosis in Amyotrophic Lateral Sclerosis Treatment

Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disease with a challenging treatment landscape, due to its complex pathogenesis and limited availability of clinical drugs. Ferroptosis, an iron-dependent form of programmed cell death (PCD), stands distinct from apoptosis, necrosis, autophagy, and other cell death mechanisms. Recent studies have increasingly highlighted the role of iron deposition, reactive oxygen species (ROS) accumulation, oxidative stress, as well as systemic Xc- and glutamate accumulation in the antioxidant system in the pathogenesis of amyotrophic lateral sclerosis. Therefore, targeting ferroptosis emerges as a promising strategy for amyotrophic lateral sclerosis treatment. This review introduces the regulatory mechanism of ferroptosis, the relationship between amyotrophic lateral sclerosis and ferroptosis, and the drugs used in the clinic, then discusses the current status of amyotrophic lateral sclerosis treatment, hoping to provide new directions and targets for its treatment.

Unlocking ferroptosis in prostate cancer - the road to novel therapies and imaging markers

Ferroptosis is a distinct form of regulated cell death that is predominantly driven by the build-up of intracellular iron and lipid peroxides. Ferroptosis suppression is widely accepted to contribute to the pathogenesis of several tumours including prostate cancer. Results from some studies reported that prostate cancer cells can be highly susceptible to ferroptosis inducers, providing potential for an interesting new avenue of therapeutic intervention for advanced prostate cancer. In this Perspective, we describe novel molecular underpinnings and metabolic drivers of ferroptosis, analyse the functions and mechanisms of ferroptosis in tumours, and highlight prostate cancer-specific susceptibilities to ferroptosis by connecting ferroptosis pathways to the distinctive metabolic reprogramming of prostate cancer cells. Leveraging these novel mechanistic insights could provide innovative therapeutic opportunities in which ferroptosis induction augments the efficacy of currently available prostate cancer treatment regimens, pending the elimination of major bottlenecks for the clinical translation of these treatment combinations, such as the development of clinical-grade inhibitors of the anti-ferroptotic enzymes as well as non-invasive biomarkers of ferroptosis. These biomarkers could be exploited for diagnostic imaging and treatment decision-making.

Rosiglitazone retards the progression of iron overload-induced osteoarthritis by impeding chondrocyte ferroptosis

Ferroptosis is implicated in several diseases, including iron overload-induced osteoarthritis (IOOA), which is marked by oxidative stress, iron imbalance, and lipid peroxidation. Given rosiglitazone's (RSG) ability to inhibit lipid peroxidation and ferroptosis, this study aims to assess its therapeutic potential for treating IOOA. Our in vitro results show that RSG targets acyl-CoA synthetase long-chain family member 4 to mitigate impairments induced by interleukin-1 beta and ferric ammonium citrate, including cell apoptosis, senescence, inflammatory responses, extracellular matrix degradation, and ferroptosis. RSG reduced intracellular iron content, alleviated oxidative stress and lipid peroxidation, mitigated damage to membrane-bound organelles, and enhanced glucose transport. Additionally, pre-treatment with RSG imparted anti-ferroptotic properties to chondrocytes. In vivo, RSG alleviated cartilage degradation, inflammatory responses, and ferroptosis in mice with IOOA. In conclusion, RSG exhibits chondroprotective and anti-ferroptotic effects by suppressing lipid peroxidation and restoring iron homeostasis, highlighting its potential for treating IOOA.

Investigating the potential risk of cadmium exposure on seizure severity and anxiety-like behaviors through the ferroptosis pathway in epileptic mice: An integrated multi-omics approach

Cadmium, a toxic heavy metal from industrial activities, poses a neurotoxic risk, especially to children. While seizures are common in children, the link between cadmium and seizure activity is unclear. Ferroptosis, an iron-dependent cell death, is key in seizure-induced hippocampal damage and related anxiety. This study aims to elucidate these mechanisms and assess the broader implications of cadmium exposure. Our research contributes in three significant areas: Firstly, through a combination of observational studies in long-term cadmium-exposed workers, Mendelian randomization analysis, NHANES analysis, urinary metabolomics, and machine learning analysis, we explored the impact of long-term cadmium exposure on inflammatory cytokines, ferroptosis-related gene expression, and lipid and iron metabolism. Secondly, by harnessing public databases for human disorders and metal-associated gene targets, alongside therapeutic molecular analyses, we identified critical human gene targets for cadmium toxicity in seizures and proposed melatonin as a promising therapeutic agent. Finally, utilizing mouse behavioral assays, T2 MRI, and MRS, we provide evidence of how prolonged cadmium exposure disrupts iron and lipid metabolism in the brain, triggering ferroptosis in the hippocampus.

Role of ACSL4 in modulating farnesoid X receptor expression and M2 macrophage polarization in HBV-induced hepatocellular carcinoma

The intricate relationship between bile acid (BA) metabolism, M2 macrophage polarization, and hepatitis B virus-hepatocellular carcinoma (HBV-HCC) necessitates a thorough investigation of ACSL4's (acyl-CoA synthetase long-chain family member 4) role. This study combines advanced bioinformatics and experimental methods to elucidate ACSL4's significance in HBV-HCC development. Using bioinformatics, we identified differentially expressed genes in HBV-HCC. STRING and gene set enrichment analysis analyses were employed to pinpoint critical genes and pathways. Immunoinfiltration analysis, along with in vitro and in vivo experiments, assessed M2 macrophage polarization and related factors. ACSL4 emerged as a pivotal gene influencing HBV-HCC. In HBV-HCC liver tissues, ACSL4 exhibited upregulation, along with increased levels of M2 macrophage markers and BA. Silencing ACSL4 led to heightened farnesoid X receptor (FXR) expression, reduced BA levels, and hindered M2 macrophage polarization, thereby improving HBV-HCC conditions. This study underscores ACSL4's significant role in HBV-HCC progression. ACSL4 modulates BA-mediated M2 macrophage polarization and FXR expression, shedding light on potential therapeutic targets and novel insights into HBV-HCC pathogenesis.

ANKRD1 aggravates renal ischaemia‒reperfusion injury via promoting TRIM25-mediated ubiquitination of ACSL3

BACKGROUND

Renal ischaemia‒reperfusion injury (IRI) is the primary cause of acute kidney injury (AKI). To date, effective therapies for delaying renal IRI and postponing patient survival remain absent. Ankyrin repeat domain 1 (ANKRD1) has been implicated in some pathophysiologic processes, but its role in renal IRI has not been explored.

METHODS

The mouse model of IRI-AKI and in vitro model were utilised to investigate the role of ANKRD1. Immunoprecipitation-mass spectrometry was performed to identify potential ANKRD1-interacting proteins. Protein‒protein interactions and protein ubiquitination were examined using immunoprecipitation and proximity ligation assay and immunoblotting, respectively. Cell viability, damage and lipid peroxidation were evaluated using biochemical and cellular techniques.

RESULTS

First, we unveiled that ANKRD1 were significantly elevated in renal IRI models. Global knockdown of ANKRD1 in all cell types of mouse kidney by recombinant adeno-associated virus (rAAV9)-mitigated ischaemia/reperfusion-induced renal damage and failure. Silencing ANKRD1 enhanced cell viability and alleviated cell damage in human renal proximal tubule cells exposed to hypoxia reoxygenation or hydrogen peroxide, while ANKRD1 overexpression had the opposite effect. Second, we discovered that ANKRD1's detrimental function during renal IRI involves promoting lipid peroxidation and ferroptosis by directly binding to and decreasing levels of acyl-coenzyme A synthetase long-chain family member 3 (ACSL3), a key protein in lipid metabolism. Furthermore, attenuating ACSL3 in vivo through pharmaceutical approach and in vitro via RNA interference mitigated the anti-ferroptotic effect of ANKRD1 knockdown. Finally, we showed ANKRD1 facilitated post-translational degradation of ACSL3 by modulating E3 ligase tripartite motif containing 25 (TRIM25) to catalyse K63-linked ubiquitination of ACSL3, thereby amplifying lipid peroxidation and ferroptosis, exacerbating renal injury.

CONCLUSIONS

Our study revealed a previously unknown function of ANKRD1 in renal IRI. By driving ACSL3 ubiquitination and degradation, ANKRD1 aggravates ferroptosis and ultimately exacerbates IRI-AKI, underlining ANKRD1's potential as a therapeutic target for kidney IRI.

KEY POINTS/HIGHLIGHTS

Ankyrin repeat domain 1 (ANKRD1) is rapidly activated in renal ischaemia‒reperfusion injury (IRI) models in vivo and in vitro. ANKRD1 knockdown mitigates kidney damage and preserves renal function. Ferroptosis contributes to the deteriorating function of ANKRD1 in renal IRI. ANKRD1 promotes acyl-coenzyme A synthetase long-chain family member 3 (ACSL3) degradation via the ubiquitin‒proteasome pathway. The E3 ligase tripartite motif containing 25 (TRIM25) is responsible for ANKRD1-mediated ubiquitination of ACSL3.

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

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

Transcriptome, histology, and enzyme activities analysis of liver in Phoxinus lagowskii to the low temperature stress and recovery

Assessing the response and resilience of fish to low temperatures over different time scales can provide valuable insights into their mechanisms of adaptation to cold conditions. Farmed Amur minnows (Phoxinus lagowskii) frequently encounter low temperatures, especially during winter. However, the specific responses of P. lagowskii to low-temperature stress remain largely unexplored. In this study, we examined serum glucose and cortisol levels, histological changes, enzymes associated with phosphate and carbohydrate metabolism, triglyceride levels, and liver transcriptomics under various conditions: control (CK), short-term cold exposure (6 days, SC), prolonged cold exposure (14 days, PC), and recovery (RY) from cold exposure at 2 °C. Liver vacuolation was observed during short-term cold exposure. Additionally, we analyzed the enzymatic activity related to carbohydrate and lipid metabolism in serum and liver. Liver transcriptomic data revealed that the PPAR signaling pathway and autophagy-related genes were enriched during short-term cold exposure. Carbohydrate metabolism-related pathways, including the AMPK and MAPK signaling pathways, were significantly enriched after prolonged cold exposure. Metabolic pathways such as fat digestion and absorption, glycine, serine, and threonine metabolism, and arginine and proline metabolism were significantly enriched in the recovery group. Rapid warming after prolonged cold stress allowed P. lagowskii to recover quickly. These findings suggest that P. lagowskii has a strong adaptive capacity for energy metabolism during prolonged cold exposure and the ability to recover rapidly from cold stress. A comprehensive examination of the histological, physiological, biochemical, and molecular responses of P. lagowskii to low temperatures is crucial for developing effective strategies for cultivating this species in challenging environments.

Quercetin and its derivatives from lotus (Nelumbo nucifera) seedpod extract combat radioresistance by suppressing ACSL4

Radioresistance poses a significant obstacle in cancer treatment. Lotus seedpod extract (LSE) has demonstrated anticancer effects in various cancer cells. However, its potential against radioresistant tumors remains unclear. In this study, we aimed to investigate the effect of LSE on radioresistant breast cancer cells, explore the underlying mechanism, and identify the major constituents responsible for its cytotoxic effect. LSE, extracted using 70% ethanol, exhibited selective cytotoxic effects against radioresistant breast cancer cells compared with their parental cells. Chemical analysis identified quercetin and its derivatives, hyperoside and miquelianin, as the major constituents responsible for these selective effects. Notably, quercetin displayed the most potent cytotoxicity against radioresistant breast cancer cells compared with hyperoside and miquelianin. Further investigation revealed that these compounds inhibited the activation of DNA repair systems, leading to the accumulation of DNA damage and the induction of apoptosis. Importantly, they efficiently suppressed the expression of ACSL4, a factor previously associated with radioresistance. In an in vivo study, quercetin exhibited a significant suppression of tumor growth in radioresistant tumor-bearing mice. Taken together, our findings highlight the potential of LSE and its major constituents, quercetin and its derivatives, in overcoming radioresistance in breast cancer. This study provides compelling evidence to support the use of LSE as a medicinal source for the future adjunctive therapy to combat radioresistance in breast cancers.

METTL3 in cancer-associated fibroblasts-derived exosomes promotes the proliferation and metastasis and suppresses ferroptosis in colorectal cancer by eliciting ACSL3 m6A modification

BACKGROUND

Cancer-associated fibroblasts (CAFs) have been reported that can affect cancer cell proliferation, metastasis, ferroptosis, and immune escape. METTL3-mediated N6-methyladenine (m6A) modification is involved in the tumorigenesis of colorectal cancer (CRC). Herein, we investigated whether METTL3-dependent m6A in CAFs-derived exosomes (exo) affected CRC progression.

METHODS

qRT-PCR and western blotting analyses detected levels of mRNAs and proteins. Cell proliferation and metastasis were evaluated using MTT, colony formation, transwell, and wound healing assays, respectively. Cell ferroptosis was assessed by detecting cell viability and the levels of Fe+, reactive oxygen species, and glutathione after erastin treatment. Exosomes were isolated from CAFs by ultracentrifugation. The m6A modification profile was determined by methylated RNA immunoprecipitation assay and the interaction between METTL3 and ACSL3 (acyl-CoA synthetase 3) was verified using dual-luciferase reporter assay. Animal models were established for in vivo analysis.

RESULTS

CAFs promoted CRC cell proliferation and metastasis, and suppressed cell ferroptosis. METTL3 was enriched in CAFs and was packaged into exosomes. The m6A modification and METTL3 expression were increased in CRC samples. Knockdown of METTL3 in CAFs-exo suppressed CRC cell proliferation and metastasis, and induced cell ferroptosis. Mechanistically, METTL3 induced ACSL3 m6A modification and stabilized its expression. The anticancer effects mediated by METTL3-silenced CAFs-exo could be rescued by ACSL3 overexpression. Moreover, in vivo assay also showed that CAFs-exo with decreased METTL3 could hinder CRC growth and metastasis in mice models.

CONCLUSION

CAFs promoted the proliferation and metastasis, and restrained the ferroptosis in CRC by exosomal METTL3-elicited ACSL3 m6A modification.

Abnormal Histopathological Expression of Klotho, Ferroptosis, and Circadian Clock Regulators in Pancreatic Ductal Adenocarcinoma: Prognostic Implications and Correlation Analyses

Pancreatic ductal adenocarcinoma (PDAC) is an extremely lethal tumor with increasing incidence, presenting numerous clinical challenges. The histopathological examination of novel, unexplored biomarkers offers a promising avenue for research, with significant translational potential for improving patient outcomes. In this study, we evaluated the prognostic significance of ferroptosis markers (TFRC, ALOX-5, ACSL-4, and GPX-4), circadian clock regulators (CLOCK, BMAL1, PER1, PER2), and KLOTHO in a retrospective cohort of 41 patients deceased by PDAC. Immunohistochemical techniques (IHC) and multiple statistical analyses (Kaplan-Meier curves, correlograms, and multinomial linear regression models) were performed. Our findings reveal that ferroptosis markers are directly associated with PDAC mortality, while circadian regulators and KLOTHO are inversely associated. Notably, TFRC emerged as the strongest risk marker associated with mortality (HR = 35.905), whereas CLOCK was identified as the most significant protective marker (HR = 0.01832). Correlation analyses indicate that ferroptosis markers are positively correlated with each other, as are circadian regulators, which also positively correlate with KLOTHO expression. In contrast, KLOTHO and circadian regulators exhibit inverse correlations with ferroptosis markers. Among the clinical variables examined, only the presence of chronic pathologies showed an association with the expression patterns of several proteins studied. These findings underscore the complexity of PDAC pathogenesis and highlight the need for further research into the specific molecular mechanisms driving disease progression.

Regulation of tumorigenesis and ferroptosis in non-small cell lung cancer by a novel BBOX1-AS1/miR-326/PROM2 axis

Dysregulation of long non-coding RNAs (lncRNAs) is associated with the tumorigenesis and ferroptosis of non-small cell lung cancer (NSCLC). BBOX1 antisense RNA 1 (BBOX1-AS1) functions as an oncogenic driver in NSCLC. Here, we aim to investigate the regulation effect and underlying mechanism of BBOX1-AS1 in NSCLC progression and ferroptosis. RNA expression was detected by quantitative real-time PCR (qRT-PCR), and protein expression was measured by immunoblotting. Cell growth was assessed by CCK-8 and colony formation assays. Transwell assay was applied to evaluate cell invasion and migration. RNA pull-down and dual-luciferase reporter assays were applied to verify the relationship between miR-326 and BBOX1-AS1 or prominin 2 (PROM2). The role of BBOX1-AS1 in NSCLC tumorigenicity was also analyzed by xenograft assays. Silencing BBOX1-AS1 or PROM2 impeded NSCLC cell growth, migration, and invasion. Silencing BBOX1-AS1 induced cell apoptosis and ferroptosis. BBOX1-AS1 up-regulated PROM2 expression, and re-expression of PROM2 reversed the effects of BBOX1-AS1 depletion on cell malignant phenotypes and ferroptosis. BBOX1-AS1 post-transcriptionally modulated PROM2 expression by sponging miR-326. MiR-326 was validated as a mediator of BBOX1-AS1 in regulating NSCLC cell malignant phenotypes and ferroptosis. Additionally, BBOX1-AS1 deficiency in vivo resulted in the suppression of xenograft tumor growth. Together, our study defines a novel BBOX1-AS1/miR-326/PROM2 axis in regulating NSCLC malignant progression and ferroptosis, offering new evidence for the oncogenic role of BBOX1-AS1 in NSCLC. These findings may provide a basis for the future usage of targeting BBOX1-AS1 in NSCLC treatment.

Targeting ferroptosis regulators in lung cancer: Exploring natural products

Lung cancer remains a formidable global health challenge, necessitating innovative therapeutic strategies for improved efficacy. This review explores the untapped potential of natural products and Traditional Chinese Medicine (TCM) in lung cancer therapy, focusing on targeting ferroptosis regulators. Natural compounds, such as curcumin and resveratrol, exhibit diverse anti-cancer mechanisms, complemented by TCM's holistic approach rooted in a 3500-year history. Emphasizing the induction of cell death, particularly ferroptosis, the review highlights its significance in overcoming challenges like resistance to conventional therapies. Key ferroptosis regulators are explored in the context of natural products and TCM. The impact of these treatments on crucial pathways, such as antioxidant mechanisms (GPX4, SLC7A11, and NRF2), iron metabolism regulators, and lipid and mitochondria pathways, is examined. The findings provide a comprehensive overview of how natural products and TCM modulate ferroptosis in lung cancer, offering valuable insights for the development of innovative, side-effect-reduced therapeutic strategies. This work holds promise for transforming the landscape of lung cancer treatment by integrating the rich resources of nature into conventional therapeutic paradigms.

Ferroptosis implication in environmental-induced neurotoxicity

Neurotoxicity, stemming from exposure to various chemical, biological, and physical agents, poses a substantial threat to the intricate network of the human nervous system. This article explores the implications of ferroptosis, a regulated form of programmed cell death characterized by iron-dependent lipid peroxidation, in environmental-induced neurotoxicity. While apoptosis has historically been recognized as a primary mechanism in neurotoxic events, recent evidence suggests the involvement of additional pathways, including ferroptosis. The study aims to conduct a comprehensive review of the existing literature on ferroptosis induced by environmental neurotoxicity across diverse agents such as natural toxins, insecticides, particulate matter, acrylamide, nanoparticles, plastic materials, metal overload, viral infections, anesthetics, chemotherapy, and radiation. The primary objective is to elucidate the diverse mechanisms through which these agents trigger ferroptosis, leading to neuronal cell death. Furthermore, the article explores potential preventive or therapeutic strategies that could mitigate ferroptosis, offering insights into protective measures against neurological damage induced by environmental stressors. This comprehensive review contributes to our evolving understanding of neurotoxicological processes, highlighting ferroptosis as a significant contributor to neuronal cell demise induced by environmental exposures. The insights gained from this study may pave the way for the development of targeted interventions to protect against ferroptosis-mediated neurotoxicity and ultimately safeguard public health.

Silencing CK19 regulates ferroptosis by affecting the expression of GPX4 and ACSL4 in oral squamous cell carcinoma in vivo and in vitro

To analyze the mechanism of how interfering with the cytokeratin 19 (CK19) pathway via the ferroptosis pathway affects tumor biological behaviors in the process of oral squamous cell carcinoma (OSCC) development. TCGA was used to analyze the expression of CK19 in pan-cancer and head and neck squamous cell carcinoma (HNSC) and to explore the ferroptosis-related genes related to HNSC. The effect of silencing CK19 on the migration ability of HSC-4 cells was verified by wound healing and migration assay. HSC-4 cells with silencing of CK19 and tumor-bearing nude mouse model were constructed. RT-qPCR, immunofluorescence and western blot were used to analyze the expression of ferroptosis-related genes. CK19 is highly expressed in human OSCC and nude mice. The migration ability of cells in the CK19-silenced group was lower than that of the control group. In vivo and in vitro, CK19 was negatively correlated with the expression of ACSL4 and positively correlated with the expression of GPX4. Compared with the control group, GPX4 expression was down-regulated and ACSL4 expression was up-regulated in the CK19-silenced group. Silencing CK19 also increased intracellular Fe2+ content and MDA content. Silencing CK19 can affect the expression of GPX4 and ACSL4 to regulate ferroptosis and at the same time increase the content of MDA, Fe2+ and ROS levels, thereby activating the regulation of ferroptosis pathway in the development of OSCC.

The role of hydrogen sulfide regulation of ferroptosis in different diseases

Ferroptosis is a programmed cell death that relies on iron and lipid peroxidation. It differs from other forms of programmed cell death such as necrosis, apoptosis and autophagy. More and more evidence indicates that ferroptosis participates in many types of diseases, such as neurodegenerative diseases, ischemia-reperfusion injury, cardiovascular diseases and so on. Hence, clarifying the role and mechanism of ferroptosis in diseases is of great significance for further understanding the pathogenesis and treatment of some diseases. Hydrogen sulfide (H2S) is a colorless and flammable gas with the smell of rotten eggs. Many years ago, H2S was considered as a toxic gas. however, in recent years, increasing evidence indicates that it is the third important gas signaling molecule after nitric oxide and carbon monoxide. H2S has various physiological and pathological functions such as antioxidant stress, anti-inflammatory, anti-apoptotic and anti-tumor, and can participate in various diseases. It has been reported that H2S regulation of ferroptosis plays an important role in many types of diseases, however, the related mechanisms are not fully clear. In this review, we reviewed the recent literature about the role of H2S regulation of ferroptosis in diseases, and analyzed the relevant mechanisms, hoping to provide references for future in-depth researches.

Unveiling the role of ferroptosis in the progression from NAFLD to NASH: recent advances in mechanistic understanding

Non-alcoholic fatty liver disease (NAFLD) is a prevalent and significant global public health issue. Nonalcoholic steatohepatitis (NASH) represents an advanced stage of NAFLD in terms of pathology. However, the intricate mechanisms underlying the progression from NAFLD to NASH remain elusive. Ferroptosis, characterized by iron-dependent cell death and distinguished from other forms of cell death based on morphological, biochemical, and genetic criteria, has emerged as a potential participant with a pivotal role in driving NAFLD progression. Nevertheless, its precise mechanism remains poorly elucidated. In this review article, we comprehensively summarize the pathogenesis of NAFLD/NASH and ferroptosis while highlighting recent advances in understanding the mechanistic involvement of ferroptosis in NAFLD/NASH.

Ferroptosis: Biology and Role in Gastrointestinal Disease

Ferroptosis is a form of nonapoptotic cell death that involves iron-dependent phospholipid peroxidation induced by accumulation of reactive oxygen species, and results in plasma membrane damage and the release of damage-associated molecular patterns. Ferroptosis has been implicated in aging and immunity, as well as disease states including intestinal and liver conditions and cancer. To date, several ferroptosis-associated genes and pathways have been implicated in liver disease. Although ferroptotic cell death is associated with dysfunction of the intestinal epithelium, the underlying molecular basis is poorly understood. As the mechanisms regulating ferroptosis become further elucidated, there is clear potential to use ferroptosis to achieve therapeutic benefit.

Exploiting cell death and tumor immunity in cancer therapy: challenges and future directions

Cancer remains a significant global challenge, with escalating incidence rates and a substantial burden on healthcare systems worldwide. Herein, we present an in-depth exploration of the intricate interplay between cancer cell death pathways and tumor immunity within the tumor microenvironment (TME). We begin by elucidating the epidemiological landscape of cancer, highlighting its pervasive impact on premature mortality and the pronounced burden in regions such as Asia and Africa. Our analysis centers on the pivotal concept of immunogenic cell death (ICD), whereby cancer cells succumbing to specific stimuli undergo a transformation that elicits robust anti-tumor immune responses. We scrutinize the mechanisms underpinning ICD induction, emphasizing the release of damage-associated molecular patterns (DAMPs) and tumor-associated antigens (TAAs) as key triggers for dendritic cell (DC) activation and subsequent T cell priming. Moreover, we explore the contributions of non-apoptotic RCD pathways, including necroptosis, ferroptosis, and pyroptosis, to tumor immunity within the TME. Emerging evidence suggests that these alternative cell death modalities possess immunogenic properties and can synergize with conventional treatments to bolster anti-tumor immune responses. Furthermore, we discuss the therapeutic implications of targeting the TME for cancer treatment, highlighting strategies to harness immunogenic cell death and manipulate non-apoptotic cell death pathways for therapeutic benefit. By elucidating the intricate crosstalk between cancer cell death and immune modulation within the TME, this review aims to pave the way for the development of novel cancer therapies that exploit the interplay between cell death mechanisms and tumor immunity and overcome Challenges in the Development and implementation of Novel Therapies.

ACSL4 promotes malignant progression of Hepatocellular carcinoma by targeting PAK2 transcription

Long-chain fatty acyl-Coa ligase 4 (ACSL4) is an important enzyme that converts fatty acids to fatty acyl-Coa esters, there is increasing evidence for its role in carcinogenesis. However, the precise role of ACLS4 in hepatocellular carcinoma (HCC) is not clearly understood. In the present study, we provide evidence that ACSL4 expression was specifically elevated in HCC and is associated with poor clinical outcomes. ACSL4 significantly promotes the growth and metastasis of HCC both in vitro and in vivo. RNA sequencing and functional experiments showed that the effect of ACSL4 on HCC development was heavily dependent on PAK2. ACSL4 expression is well correlated with PAK2 in HCC, and ACSL4 even transcriptionally increased PAK2 gene expression mediated by Sp1. In addition, emodin, a naturally occurring anthraquinone derivative, inhibited HCC cell growth and tumor progression by targeting ACSL4. In summary, ACSL4 plays a novel oncogene in HCC development by regulating PAK2 transcription. Targeting ACSL4 could be useful in drug development and therapy for HCC.

Investigating the Therapeutic Effects of Ferroptosis on Myocardial Ischemia-Reperfusion Injury Using a Dual-Locking Mitochondrial Targeting Strategy

Research on ferroptosis in myocardial ischemia/reperfusion injury (MIRI) using mitochondrial viscosity as a nexus holds great promise for MIRI therapy. However, high-precision visualisation of mitochondrial viscosity remains a formidable task owing to the debilitating electrostatic interactions caused by damaged mitochondrial membrane potential. Herein, we propose a dual-locking mitochondria-targeting strategy that incorporates electrostatic forces and probe-protein molecular docking. Even in damaged mitochondria, stable and precise visualisation of mitochondrial viscosity in triggered and medicated MIRI was achieved owing to the sustained driving forces (e.g., pi-cation, pi-alkyl interactions, etc.) between the developed probe, CBS, and the mitochondrial membrane protein. Moreover, complemented by a western blot, we confirmed that ferrostatin-1 exerts its therapeutic effect on MIRI by improving the system xc-/GSH/GPX4 antioxidant system, confirming the therapeutic value of ferroptosis in MIRI. This study presents a novel strategy for developing robust mitochondrial probes, thereby advancing MIRI treatment.

Ferroptosis and its role in gastric and colorectal cancers

Ferroptosis is a novel mechanism of programmed cell death, characterized by intracellular iron overload, intensified lipid peroxidation, and abnormal accumulation of reactive oxygen species, which ultimately resulting in cell membrane impairment and demise. Research has revealed that cancer cells exhibit a greater demand for iron compared to normal cells, indicating a potential susceptibility of cancer cells to ferroptosis. Stomach and colorectal cancers are common gastrointestinal malignancies, and their elevated occurrence and mortality rates render them a global health concern. Despite significant advancements in medical treatments, certain unfavorable consequences and drug resistance persist. Consequently, directing attention towards the phenomenon of ferroptosis in gastric and colorectal cancers holds promise for enhancing therapeutic efficacy. This review aims to elucidate the intricate cellular metabolism associated with ferroptosis, encompassing lipid and amino acid metabolism, as well as iron metabolic processes. Furthermore, the significance of ferroptosis in the context of gastric and colorectal cancer is thoroughly examined and discussed.

Futile lipid cycling: from biochemistry to physiology

In the healthy state, the fat stored in our body isn't just inert. Rather, it is dynamically mobilized to maintain an adequate concentration of fatty acids (FAs) in our bloodstream. Our body tends to produce excess FAs to ensure that the FA availability is not limiting. The surplus FAs are actively re-esterified into glycerides, initiating a cycle of breakdown and resynthesis of glycerides. This cycle consumes energy without generating a new product and is commonly referred to as the 'futile lipid cycle' or the glyceride/FA cycle. Contrary to the notion that it's a wasteful process, it turns out this cycle is crucial for systemic metabolic homeostasis. It acts as a control point in intra-adipocyte and inter-organ cross-talk, a metabolic rheostat, an energy sensor and a lipid diversifying mechanism. In this Review, we discuss the metabolic regulation and physiological implications of the glyceride/FA cycle and its mechanistic underpinnings.

Identification of potential key ferroptosis- and autophagy-related genes in myelomeningocele through bioinformatics analysis

Myelomeningocele is a common congenital anomaly associated with polygenic disorders worldwide. However, the intricate molecular mechanisms underlying myelomeningocele remain elusive. To investigate whether ferroptosis and ferritinophagy contribute to the pathomechanism of myelomeningocele, differentially expressed genes (DEGs) were identified as novel biomarker and potential treatment agents. The GSE101141 dataset from Gene Expression Omnibus (GEO) was analyzed using GEO2R web tool to obtain DEGs based on |log2 fold change (FC)|≥1.5 and p < 0.05. Two datasets from the Ferroptosis Database (481 genes) and Autophagy Database (551 genes) were intersected with the DEGs from the GSE101141 dataset to identify ferroptosis- and autophagy-related DEGs using Venn diagrams. Functional and pathway enrichment, protein-protein interaction (PPI) network analyses were performed, and candidate genes were selected. Transcription factors (TFs), microRNAs (miRNAs), diseases and chemicals interacting with the candidate genes were identified. Receiver operating characteristic (ROC) curve analysis was performed to validate the diagnostic value of the candidate genes. Sixty ferroptosis-related and 74 autophagy-related DEGs were identified. These DEGs are involved in FoxO signaling pathway. Six candidate genes (EGFR, KRAS, IL1B, SIRT1, ATM, and MAPK8) were selected. miRNAs such as hsa-miR-27a-3p, hsa-miR-877-5p, and hsa-miR-892b, and TFs including P53, POU3F2, TATA are involved in regulation of candidate genes. Diseases such as schizophrenia, fibrosis, and neoplasms are the most relevant to the candidate genes. Chemicals, such as resveratrol, curcumin, and quercetin may have significant implications in the treatment of myelomeningocele. The candidate genes, especially MAPK8, also showed a high diagnostic value for myelomeningocele. These results help to shed light on the molecular mechanism of myelomeningocele and may provide new insights into diagnostic biomarker in the amniotic fluid and potential therapeutic agents of myelomeningocele.

Ferroptosis in age-related vascular diseases: Molecular mechanisms and innovative therapeutic strategies

Aging, an inevitable aspect of human existence, serves as one of the predominant risk factors for vascular diseases. Delving into the mystery of vascular disease's pathophysiology, the profound involvement of programmed cell death (PCD) has been extensively demonstrated. PCD is a fundamental biological process that plays a crucial role in both normal physiology and pathology, including a recently discovered form, ferroptosis. Ferroptosis is characterized by its reliance on iron and lipid peroxidation, and its significant involvement in vascular disease pathophysiology has been increasingly acknowledged. This phenomenon not only offers a promising therapeutic target but also deepens our understanding of the complex relationship between ferroptosis and age-related vascular diseases. Consequently, this article aims to thoroughly review the mechanisms that enable the effective control and inhibition of ferroptosis. It focuses on genetic and pharmacological interventions, with the goal of developing innovative therapeutic strategies to combat age-related vascular diseases.

METTL3 promotes trophoblast ferroptosis in preeclampsia by stabilizing the ACSL4 m6A modification

This study aims to explore the role of methyltransferase-like 3 (METTL3) modulation of ferroptosis in the pathogenesis of trophoblast-mediated preeclampsia. The expression of METTL3 and acyl-CoA synthetase long chain family member 4 (ACSL4) was measured in clinical placental tissues and trophoblasts using qPCR and Western blot techniques. The effects of METTL3 on the symptoms of preeclampsia were also validated in rat models. METTL3 and ACSL4 were upregulated in placental tissues from patients with preeclampsia and in hypoxia-induced trophoblasts. METTL3 silencing increased the migration and invasion of trophoblasts cultured under hypoxic conditions. Knockdown of METTL3 increased cell viability and suppressed ferroptosis in hypoxia-stimulated trophoblasts. Hypoxia increased the level of m6A in cells, whereas silencing METTL3 partially reversed this change. Silencing METTL3 resulted in a decrease in m6A modification of ACSL4 mRNA, which led to a reduction in ACSL4 mRNA stability. ACSL4 upregulation partially reversed the effects of METTL3 silencing on cell viability, migration, invasion, and ferroptosis in hypoxia-stimulated trophoblasts. Inhibition of METTL3 in preeclampsia rats decreased blood pressure, urine protein levels, fetal survival rate, and ACSL4-mediated ferroptosis. METTL3 elevates ferroptosis to inhibit the migration and invasion of trophoblasts and in vivo preeclampsia symptoms by catalyzing the m6A modification of ACSL4 mRNA.

Impact of ACSL4 on the prognosis of hepatocellular carcinoma: Association with cancer-associated fibroblasts and the tumour immune microenvironment

BACKGROUND & AIMS

Recently, the association between hepatocellular carcinoma (HCC) and ferroptosis has been the focus of much attention. The expression of long chain fatty acyl-CoA ligase 4 (ACSL4), a marker of ferroptosis, in tumour tissue is related to better prognosis in various cancers. In HCC, ACSL4 expression indicates poor prognosis and is related to high malignancy. However, the mechanism remains to be fully understood.

METHODS

We retrospectively enrolled 358 patients with HCC who had undergone hepatic resection. Immunohistochemistry (IHC) for ACSL4 was performed. Factors associated with ASCL4 expression were investigated by spatial transcriptome analysis, and the relationships were investigated by IHC. The association between ACSL4 and the tumour immune microenvironment was examined in a public dataset and investigated by IHC.

RESULTS

Patients were divided into ACSL4-positive (n = 72, 20.1%) and ACSL4-negative (n = 286, 79.9%) groups. ACSL4 positivity was significantly correlated with higher α-fetoprotein (p = .0180) and more histological liver fibrosis (p = .0014). In multivariate analysis, ACSL4 positivity was an independent prognostic factor (p < .0001). Spatial transcriptome analysis showed a positive correlation between ACSL4 and cancer-associated fibroblasts; this relationship was confirmed by IHC. Evaluation of a public dataset showed the correlation between ACSL4 and exhausted tumour immune microenvironment; this relationship was also confirmed by IHC.

CONCLUSION

ACSL4 is a prognostic factor in HCC patients and its expression was associated with cancer-associated fibroblasts and anti-tumour immunity.

Co-Expression Network Analysis Unveiled lncRNA-mRNA Links Correlated to Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor Resistance and/or Intermediate Epithelial-to-Mesenchymal Transition Phenotypes in a Human Non-Small Cell Lung Cancer Cellular Model System

We investigated mRNA-lncRNA co-expression patterns in a cellular model system of non-small cell lung cancer (NSCLC) sensitive and resistant to the epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) erlotinib/gefitinib. The aim of this study was to unveil insights into the complex mechanisms of NSCLC targeted therapy resistance and epithelial-to-mesenchymal transition (EMT). Genome-wide RNA expression was quantified for weighted gene co-expression network analysis (WGCNA) to correlate the expression levels of mRNAs and lncRNAs. Functional enrichment analysis and identification of lncRNAs were conducted on modules associated with the EGFR-TKI response and/or intermediate EMT phenotypes. We constructed lncRNA-mRNA co-expression networks and identified key modules and their enriched biological functions. Processes enriched in the selected modules included RHO (A, B, C) GTPase and regulatory signaling pathways, apoptosis, inflammatory and interleukin signaling pathways, cell adhesion, cell migration, cell and extracellular matrix organization, metabolism, and lipid metabolism. Interestingly, several lncRNAs, already shown to be dysregulated in cancer, are connected to a small number of mRNAs, and several lncRNAs are interlinked with each other in the co-expression network.

Regulation of ferroptosis by PI3K/Akt signaling pathway: a promising therapeutic axis in cancer

The global challenge posed by cancer, marked by rising incidence and mortality rates, underscores the urgency for innovative therapeutic approaches. The PI3K/Akt signaling pathway, frequently amplified in various cancers, is central in regulating essential cellular processes. Its dysregulation, often stemming from genetic mutations, significantly contributes to cancer initiation, progression, and resistance to therapy. Concurrently, ferroptosis, a recently discovered form of regulated cell death characterized by iron-dependent processes and lipid reactive oxygen species buildup, holds implications for diseases, including cancer. Exploring the interplay between the dysregulated PI3K/Akt pathway and ferroptosis unveils potential insights into the molecular mechanisms driving or inhibiting ferroptotic processes in cancer cells. Evidence suggests that inhibiting the PI3K/Akt pathway may sensitize cancer cells to ferroptosis induction, offering a promising strategy to overcome drug resistance. This review aims to provide a comprehensive exploration of this interplay, shedding light on the potential for disrupting the PI3K/Akt pathway to enhance ferroptosis as an alternative route for inducing cell death and improving cancer treatment outcomes.

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

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

Antioxidant Systems as Modulators of Ferroptosis: Focus on Transcription Factors

Ferroptosis is a type of programmed cell death that differs from apoptosis, autophagy, and necrosis and is related to several physio-pathological processes, including tumorigenesis, neurodegeneration, senescence, blood diseases, kidney disorders, and ischemia-reperfusion injuries. Ferroptosis is linked to iron accumulation, eliciting dysfunction of antioxidant systems, which favor the production of lipid peroxides, cell membrane damage, and ultimately, cell death. Thus, signaling pathways evoking ferroptosis are strongly associated with those protecting cells against iron excess and/or lipid-derived ROS. Here, we discuss the interaction between the metabolic pathways of ferroptosis and antioxidant systems, with a particular focus on transcription factors implicated in the regulation of ferroptosis, either as triggers of lipid peroxidation or as ferroptosis antioxidant defense pathways.

Iron-induced kidney cell damage: insights into molecular mechanisms and potential diagnostic significance of urinary FTL

Background: Iron overload can lead to organ and cell injuries. Although the mechanisms of iron-induced cell damage have been extensively studied using various cells, little is known about these processes in kidney cells. Methods: In this study, we first examined the correlation between serum iron levels and kidney function. Subsequently, we investigated the molecular impact of excess iron on kidney cell lines, HEK293T and HK-2. The presence of the upregulated protein was further validated in urine. Results: The results revealed that excess iron caused significant cell death accompanied by morphological changes. Transcriptomic analysis revealed an up-regulation of the ferroptosis pathway during iron treatment. This was confirmed by up-regulation of ferroptosis markers, ferritin light chain (FTL), and prostaglandin-endoperoxide synthase 2 (PTGS2), and down-regulation of acyl-CoA synthetase long-chain family member 4 (ACSL4) and glutathione peroxidase 4 (GPX4) using real-time PCR and Western blotting. In addition, excess iron treatment enhanced protein and lipid oxidation. Supportively, an inverse correlation between urinary FTL protein level and kidney function was observed. Conclusion: These findings suggest that excess iron disrupts cellular homeostasis and affects key proteins involved in kidney cell death. Our study demonstrated that high iron levels caused kidney cell damage. Additionally, urinary FTL might be a useful biomarker to detect kidney damage caused by iron toxicity. Our study also provided insights into the molecular mechanisms of iron-induced kidney injury, discussing several potential targets for future interventions.

Ferroptosis contributes to JEV-induced neuronal damage and neuroinflammation

Ferroptosis is a newly discovered prototype of programmed cell death (PCD) driven by iron-dependent phospholipid peroxidation ​accumulation, and it has been linked to numerous organ injuries and degenerative pathologies. Although studies have shown that a variety of cell death processes contribute to JEV-induced neuroinflammation and neuronal injury, there is currently limited research on the specific involvement of ferroptosis. In this study, we explored the neuronal ferroptosis induced by JEV infection in vitro and in vivo. Our results indicated that JEV infection induces neuronal ferroptosis through inhibiting the function of the antioxidant system mediated by glutathione (GSH)/glutathione peroxidase 4 (GPX4), as well as by promoting lipid peroxidation mediated by yes-associated protein 1 (YAP1)/long-chain acyl-CoA synthetase 4 (ACSL4). Further analyses revealed that JEV E and prM proteins function as agonists, inducing ferroptosis. Moreover, we found that treatment with a ferroptosis inhibitor in JEV-infected mice reduces the viral titers and inflammation in the mouse brains, ultimately improving the survival rate of infected mice. In conclusion, our study unveils a critical role of ferroptosis in the pathogenesis of JEV, providing new ideas for the prevention and treatment of viral encephalitis.

Fluorene-9-bisphenol exposure damages the testis in mice through a novel mechanism of ferroptosis

Fluorene-9-bisphenol (BHPF) is an emerging global endocrine-disrupting chemical found in numerous household products as a substitute of bisphenol A. Many studies have reported various toxicities associated with BHPF. However, the effect of BHPF on male reproduction, particularly on the structural integrity of the blood testis barrier (BTB) in mice, has not yet been extensively studied. Ferroptosis, a newly identified form of cell death, occurs in the testicular tissue following exposure to BPA, affecting male fertility. We investigated whether ferroptosis plays a role in BHPF-induced testicular damage. The findings indicated that BHPF exposure led decreases in serum testosterone (T) concentration and sperm concentration and motility in mice. Furthermore, BHPF disrupted the BTB by interfering with key BTB-related proteins, including Cx43, β-catenin, and ZO-1. Moreover, BHPF induced ferroptosis through the induction of lipid peroxidation, iron overload, oxidative stress, and mitochondrial dysfunction in the testicular tissue. Inhibition of ferroptosis using Fer-1 mitigated the BHPF-induced damage to the BTB and ferroptosis in TM4 cells. Overall, our findings indicated the detrimental effects of BHPF on male reproductive function in mice, suggesting ferroptosis as a mechanism underlying testicular damage.

CYLD regulates cell ferroptosis through Hippo/YAP signaling in prostate cancer progression

Prostate cancer (PCa) is one of the most common malignancy in men. However, the molecular mechanism of its pathogenesis has not yet been elucidated. In this study, we demonstrated that CYLD, a novel deubiquitinating enzyme, impeded PCa development and progression via tumor suppression. First, we found that CYLD was downregulated in PCa tissues, and its expression was inversely correlated with pathological grade and clinical stage. Moreover, we discovered that CYLD inhibited tumor cell proliferation and enhanced the sensitivity to cell ferroptosis in PCa in vitro and in vivo, respectively. Mechanistically, we demonstrated that CYLD suppressed the ubiquitination of YAP protein, then promoted ACSL4 and TFRC mRNA transcription. Then, we demonstrated that CYLD could enhance the sensitivity of PCa xenografts to ferroptosis in vivo. Furthermore, we discovered for the first time that there was a positive correlation between CYLD expression and ACSL4 or TFRC expression in human PCa specimens. The results of this study suggested that CYLD acted as a tumor suppressor gene in PCa and promoted cell ferroptosis through Hippo/YAP signaling.

Ubiquitination plays an important role during the formation of chicken primordial germ cells

As an important posttranslational modification, ubiquitination plays an important role in regulating protein homeostasis in eukaryotic cells. In our previous studies, both the transcriptome and proteome suggested that ubiquitination is involved in the formation of chicken primordial germ cells (PGCs). Here, affinity enrichment combined with liquid chromatography-tandem mass spectrometry (MS/MS) was used to analyze the ubiquitome during the differentiation from embryonic stem cells to PGCs, and we identify that 724 lysine ubiquitinated sites were up-regulated in 558 proteins and 138 lysine ubiquitinated sites were down-regulated in 109 proteins. Furthermore, GO and KEGG enrichment analysis showed that ubiquitination regulates key proteins to participate in the progression of key events related to PGC formation and the transduction of key signals such as Wnt, MAPK, and insulin signals, followed by the detailed explanation of the specific regulatory mechanism of ubiquitination through the combined proteome and ubiquitome analysis. Moreover, both the activation and inhibition of neddylation were detrimental to the maintenance of the biological characteristics of PGCs, which also verified the importance of ubiquitination. In conclusion, this study provides a global view of the ubiquitome during the formation of PGCs by label-free quantitative ubiquitomics, which lays a theoretical foundation for the formation mechanism and specific application of chicken PGCs.

Thrombin induces ferroptosis in triple-negative breast cancer through the cPLA2α/ACSL4 signaling pathway

Ferroptosis is a recently identified form of regulated cell death that plays a crucial role in tumor suppression. In this study, we found that F2 (the gene encoding thrombin) was strongly upregulated in breast cancer (BRCA, TCGA Study Abbreviations) compared with normal samples and that lower F2 levels were associated with poorer prognosis in breast cancer patients. Thrombin induces ferroptosis in triple-negative breast cancer (TNBC) cells by activation of cytosolic phospholipase A2α (cPLA2α) activity to increase the release of arachidonic acid (AA). TNBC in all breast cancer subtypes exhibited the highest levels of PLA2G4A (the gene encoding cPLA2α) and Acsl4, and inhibition of cPLA2α and its downstream enzyme acyl-CoA synthetase long-chain family member 4 (ACSL4) reversed thrombin toxicity. In a mouse xenograft model of TNBC, thrombin treatment suppressed breast cancer growth which can be inhibited by ferroptosis inhibitor Liproxstatin-1 (Lip-1). Our study underscores the potential of the thrombin-ACSL4 axis as a promising therapeutic target for the treatment of TNBC.

Polyphyllin I induces ferroptosis in castration-resistant prostate cancer cells through the ERK/DNMT1/ACSL4 axis

BACKGROUND

Castration-resistant prostate cancer (CRPC) inevitably arises after androgen deprivation therapy (ADT). Therefore, there is an urgent need to search for novel treatment strategies for CRPC. Polyphyllin I (PPI), one of the steroidal saponins in paris polyphylla, has been shown to have an anticancer effect. This study investigated the role and mechanism of PPI in CRPC cell ferroptosis.

METHODS

Protein levels of GPX4, p-extracellular regulated protein kinases (ERK), ERK, DNMT1, and ACSL4 were measured by Western blot. DNMT1 and ACSL4 mRNA expression was analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Prostate cancer cells (DU145, PC3) were treated with PPI. Cell viability was assessed utilizing Cell Counting Kit-8 (CCK-8) assay. The role of PPI in regulating ferroptosis was determined by analyzing lipid reactive oxygen species (ROS), malonyl dialdehyde (MDA), iron (Fe2+ ), and glutathione (GSH) content. Chromatin immunoprecipitation (ChIP) assay verified the effect of DNMT1 on the ACSL4 promoter. The methylation level of ACSL4 promoter was assessed utilizing MSP. A nude mice xenograft was adopted to detect the effect of PPI in vivo.

RESULTS

PPI inhibited CRPC cell proliferation, reduced levels of GSH and GPX4, and increased levels of MDA, Fe2+ , and ROS, while ERK inhibitor reversed the effect of PPI on ferroptosis. PPI repressed the methylation level of ACSL4 promoter by inhibiting DNMT1. DNMT1 knockdown promoted CRPC cell ferroptosis by regulating ACSL4. PPI induced ferroptosis and suppressed CRPC growth in nude mice.

CONCLUSION

PPI can be used as a ferroptosis inducer to induce ferroptosis in CRPC cells via the ERK/DNMT1/ACSL4 axis, suggesting that PPI may be a new strategy for CRPC treatment.

Targeting ferroptosis in gastric cancer: Strategies and opportunities

Ferroptosis is a novel form of programmed cell death morphologically, genetically, and biochemically distinct from other cell death pathways and characterized by the accumulation of iron-dependent lipid peroxides and oxidative damage. It is now understood that ferroptosis plays an essential role in various biological processes, especially in the metabolism of iron, lipids, and amino acids. Gastric cancer (GC) is a prevalent malignant tumor worldwide with low early diagnosis rates and high metastasis rates, accounting for its relatively poor prognosis. Although chemotherapy is commonly used to treat GC, drug resistance often leads to poor therapeutic outcomes. In the last several years, extensive research on ferroptosis has highlighted its significant potential in GC therapy, providing a promising strategy to address drug resistance associated with standard cancer therapies. In this review, we offer an extensive summary of the key regulatory factors related to the mechanisms underlying ferroptosis. Various inducers and inhibitors specifically targeting ferroptosis are uncovered. Additionally, we explore the prospective applications and outcomes of these agents in the field of GC therapy, emphasizing their capacity to improve the outcomes of this patient population.