Long non-coding RNA NEAT1 regulates ferroptosis sensitivity in non-small-cell lung cancer

Emerging roles of long noncoding RNAs in enzymes related intracellular metabolic pathways in cancer biology

Metabolic reprogramming plays critical roles in the development and progression of tumor by providing cancer cells with a sufficient supply of nutrients and other factors needed for fast-proliferating. Emerging evidence indicates that long noncoding RNAs (lncRNAs) are involved in the initiation of metastasis via regulating the metabolic reprogramming in various cancers. In this paper, we aim to summarize that lncRNAs could participate in intracellular nutrient metabolism including glucose, amino acid, lipid, and nucleotide, regardless of whether lncRNAs have tumor-promoting or tumor-suppressor function. Meanwhile, modulation of lncRNAs in glucose metabolic enzymes in glycolysis, pentose phosphate pathway and tricarboxylic acid cycle (TCA) in cancer is reviewed. We also discuss therapeutic strategies targeted at interfering with enzyme activity to decrease the utilization of glucoses, amino acid, nucleotide acid and lipid in tumor cells. This review focuses on our current understanding of lncRNAs participating in cancer cell metabolic reprogramming, paving the way for further investigation into the combination of such approaches with existing anti-cancer therapies.

Ferroptosis and hepatocellular carcinoma: the emerging role of lncRNAs

Hepatocellular carcinoma is the most common form of primary liver cancer and poses a significant challenge to the medical community because of its high mortality rate. In recent years, ferroptosis, a unique form of cell death, has garnered widespread attention. Ferroptosis, which is characterized by iron-dependent lipid peroxidation and mitochondrial alterations, is closely associated with the pathological processes of various diseases, including hepatocellular carcinoma. Long non-coding RNAs (lncRNAs), are a type of functional RNA, and play crucial regulatory roles in a variety of biological processes. In this manuscript, we review the regulatory roles of lncRNAs in the key aspects of ferroptosis, and summarize the research progress on ferroptosis-related lncRNAs in hepatocellular carcinoma.

Induction of ferroptosis by natural products in non-small cell lung cancer: a comprehensive systematic review

Lung cancer is one of the leading causes of cancer-related deaths worldwide that presents a substantial peril to human health. Non-Small Cell Lung Cancer (NSCLC) is a main subtype of lung cancer with heightened metastasis and invasion ability. The predominant treatment approaches currently comprise surgical interventions, chemotherapy regimens, and radiotherapeutic procedures. However, it poses significant clinical challenges due to its tumor heterogeneity and drug resistance, resulting in diminished patient survival rates. Therefore, the development of novel treatment strategies for NSCLC is necessary. Ferroptosis was characterized by iron-dependent lipid peroxidation and the accumulation of lipid reactive oxygen species (ROS), leading to oxidative damage of cells and eventually cell death. An increasing number of studies have found that exploiting the induction of ferroptosis may be a potential therapeutic approach in NSCLC. Recent investigations have underscored the remarkable potential of natural products in the cancer treatment, owing to their potent activity and high safety profiles. Notably, accumulating evidences have shown that targeting ferroptosis through natural compounds as a novel strategy for combating NSCLC holds considerable promise. Nevertheless, the existing literature on comprehensive reviews elucidating the role of natural products inducing the ferroptosis for NSCLC therapy remains relatively sparse. In order to furnish a valuable reference and support for the identification of natural products inducing ferroptosis in anti-NSCLC therapeutics, this article provided a comprehensive review explaining the mechanisms by which natural products selectively target ferroptosis and modulate the pathogenesis of NSCLC.

Emerging mechanisms of ferroptosis and its implications in lung cancer

ABSTRACT

Lung cancer is one of the most common malignancies and has the highest number of deaths among all cancers. Despite continuous advances in medical strategies, the overall survival of lung cancer patients is still low, probably due to disease progression or drug resistance. Ferroptosis is an iron-dependent form of regulated cell death triggered by the lethal accumulation of lipid peroxides, and its dysregulation is implicated in cancer development. Preclinical evidence has shown that targeting the ferroptosis pathway could be a potential strategy for improving lung cancer treatment outcomes. In this review, we summarize the underlying mechanisms and regulatory networks of ferroptosis in lung cancer and highlight ferroptosis-targeting preclinical attempts to provide new insights for lung cancer treatment.

[Role of Ferroptosis in Non-small Cell Lung Cancer and Progress of Traditional Chinese Medicine Intervention]

Non-small cell lung cancer (NSCLC) is one of the malignant tumors with high morbidity and mortality worldwide. Ferroptosis is a new type of programmed cell death caused by abnormal accumulation of iron-dependent reactive oxygen species (ROS) leading to lipid peroxidation. It involves the balance between iron metabolism, lipid metabolism, oxygen free radical reaction and lipid peroxidation. Recent studies have found that ferroptosis is closely related to the occurrence and development of NSCLC. Due to the emergence of chemotherapy resistance and radiotherapy resistance in the treatment of NSCLC, there is an urgent need to develop new effective drugs and treatment strategies. Traditional Chinese medicine has unique advantages in the prevention and treatment of NSCLC due to its multi-targets and minimal side effects. In this review, we summarize the mechanism of ferroptosis in NSCLC, and discuss the research status of active ingredients of traditional Chinese medicine, single-herb traditional Chinese medicine and Chinese herbal compounds in the intervention of NSCLC through ferroptosis, in order to provide a new theoretical basis for the research of ferroptosis pathway and the prevention and treatment of NSCLC by targeted ferroptosis of traditional Chinese medicine.
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POU2F2-mediated upregulation of lncRNA PTPRG-AS1 inhibits ferroptosis in breast cancer via miR-376c-3p/SLC7A11 axis

Background: Triple-negative breast cancer (TNBC) is a subtype of BC with high rates of mortality. The mechanism of PTPRG-AS1 in ferroptosis of TNBC was investigated. Methods: Chromatin immunoprecipitation and dual-luciferase reporter assays were used to measure intermolecular relationships. MTT and colony formation assays detected cell viability and proliferation. Kits detected Fe2+ and reactive oxygen species levels. The role of PTPRG-AS1 in tumor growth was analyzed in vivo. Results: PTPRG-AS1 was increased in TNBC tissues and cells. PTPRG-AS1 silencing increased the reduction of glutathione and GPX4, increased Fe2+ and reactive oxygen species in erastin-treated cells and inhibited proliferation. POU2F2 transcriptionally upregulated PTPRG-AS1. PTPRG-AS1 targeted miR-376c-3p to upregulate SLC7A11. PTPRG-AS1 knockdown suppressed tumor growth in vivo. Conclusion: POU2F2 transcriptionally activates PTPRG-AS1 to modulate ferroptosis and proliferation by miR-376c-3p/SLC7A11, promoting TNBC.

Ferroptosis: a promising candidate for exosome-mediated regulation in different diseases

Ferroptosis is a newly discovered form of cell death that is featured in a wide range of diseases. Exosome therapy is a promising therapeutic option that has attracted much attention due to its low immunogenicity, low toxicity, and ability to penetrate biological barriers. In addition, emerging evidence indicates that exosomes possess the ability to modulate the progression of diverse diseases by regulating ferroptosis in damaged cells. Hence, the mechanism by which cell-derived and noncellular-derived exosomes target ferroptosis in different diseases through the system Xc-/GSH/GPX4 axis, NAD(P)H/FSP1/CoQ10 axis, iron metabolism pathway and lipid metabolism pathway associated with ferroptosis, as well as its applications in liver disease, neurological diseases, lung injury, heart injury, cancer and other diseases, are summarized here. Additionally, the role of exosome-regulated ferroptosis as an emerging repair mechanism for damaged tissues and cells is also discussed, and this is expected to be a promising treatment direction for various diseases in the future. Video Abstract.

Modulation of ferroptosis by non‑coding RNAs in cancers: Potential biomarkers for cancer diagnose and therapy

Ferroptosis is a recently discovered cell programmed death. Extensive researches have indicated that ferroptosis plays an essential role in tumorigenesis, development, migration and chemotherapy drugs resistance, which makes it become a new target for tumor therapy. Non-coding RNAs (ncRNAs) are considered to control a wide range of cellular processes by modulating gene expression. Recent studies have indicated that ncRNAs regulate the process of ferroptosis via various pathway to affect the development of cancer. However, the regulation network remains ambiguous. In this review, we outlined the major metabolic processes of ferroptosis and concluded the relationship between ferroptosis-related ncRNAs and cancer progression. In addition, the prospect of ncRNAs being new therapeutic targets and early diagnosis biomarkers for cancer by regulating ferroptosis were presented, and the possible obstacles were also predicted. This could help in discovering novel cancer early diagnostic methods and therapeutic approaches.

Natural compounds efficacy in complicated diabetes: A new twist impacting ferroptosis

Ferroptosis, as a way of cell death, participates in the body's normal physiological and pathological regulation. Recent studies have shown that ferroptosis may damage glucose-stimulated islets β Insulin secretion and programmed cell death of T2DM target organs are involved in the pathogenesis of T2DM and its complications. Targeting suppression of ferroptosis with specific inhibitors may provide new therapeutic opportunities for previously untreated T2DM and its target organs. Current studies suggest that natural bioactive compounds, which are abundantly available in drugs, foods, and medicinal plants for the treatment of T2DM and its target organs, have recently received significant attention for their various biological activities and minimal toxicity, and that many natural compounds appear to have a significant role in the regulation of ferroptosis in T2DM and its target organs. Therefore, this review summarized the potential treatment strategies of natural compounds as ferroptosis inhibitors to treat T2DM and its complications, providing potential lead compounds and natural phytochemical molecular nuclei for future drug research and development to intervene in ferroptosis in T2DM.

Acyl-CoA synthase ACSL4: an essential target in ferroptosis and fatty acid metabolism

ABSTRACT

Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.

Noncoding RNAs in cancer ferroptosis: From biology to clinical opportunity

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

Ferroptosis in tumors and its relationship to other programmed cell death: role of non-coding RNAs

Programmed cell death (PCD) plays an important role in many aspects of individual development, maintenance of body homeostasis and pathological processes. Ferroptosis is a novel form of PCD characterized by the accumulation of iron-dependent lipid peroxides resulting in lethal cell damage. It contributes to tumor progression in an apoptosis-independent manner. In recent years, an increasing number of non-coding RNAs (ncRNAs) have been demonstrated to mediate the biological process of ferroptosis, hence impacting carcinogenesis, progression, drug resistance, and prognosis. However, the clear regulatory mechanism for this phenomenon remains poorly understood. Moreover, ferroptosis does not usually exist independently. Its interaction with PCD, like apoptosis, necroptosis, autophagy, pyroptosis, and cuproptosis, to destroy cells appears to exist. Furthermore, ncRNA seems to be involved. Here, we review the mechanisms by which ferroptosis occurs, dissect its relationship with other forms of death, summarize the key regulatory roles played by ncRNAs, raise relevant questions and predict possible barriers to its application in the clinic, offering new ideas for targeted tumour therapy.

LncRNAs and regulated cell death in tumor cells

Regulated Cell Death (RCD) is a mode of cell death that occurs through drug or genetic intervention. The regulation of RCDs is one of the significant reasons for the long survival time of tumor cells and poor prognosis of patients. Long non-coding RNAs (lncRNAs) which are involved in the regulation of tumor biological processes, including RCDs occurring on tumor cells, are closely related to tumor progression. In this review, we describe the mechanisms of eight different RCDs which contain apoptosis, necroptosis, pyroptosis, NETosis, entosis, ferroptosis, autosis and cuproptosis. Meanwhile, their respective roles in the tumor are aggregated. In addition, we outline the literature that is related to the regulatory relationships between lncRNAs and RCDs in tumor cells, which is expected to provide new ideas for tumor diagnosis and treatment.

Long non-coding RNAs and gastric cancer: An update of potential biomarkers and therapeutic applications

The frequent metastasis of gastric cancer (GC) complicates the cure and therefore the development of effective diagnostic and therapeutic approaches is urgently necessary. In recent years, lncRNA has emerged as a drug target in the treatment of GC, particularly in the areas of cancer immunity, cancer metabolism, and cancer metastasis. This has led to the demonstration of the importance of these RNAs as prognostic, diagnostic and therapeutic agents. In this review, we provide an overview of the biological activities of lncRNAs in GC development and update the latest pathological activities, prognostic and diagnostic strategies, and therapeutic options for GC-related lncRNAs.

Ferroptosis in lung cancer: a novel pathway regulating cell death and a promising target for drug therapy

Lung cancer is a common malignant tumor that occurs in the human body and poses a serious threat to human health and quality of life. The existing treatment methods mainly include surgical treatment, chemotherapy, and radiotherapy. However, due to the strong metastatic characteristics of lung cancer and the emergence of related drug resistance and radiation resistance, the overall survival rate of lung cancer patients is not ideal. There is an urgent need to develop new treatment strategies or new effective drugs to treat lung cancer. Ferroptosis, a novel type of programmed cell death, is different from the traditional cell death pathways such as apoptosis, necrosis, pyroptosis and so on. It is caused by the increase of iron-dependent reactive oxygen species due to intracellular iron overload, which leads to the accumulation of lipid peroxides, thus inducing cell membrane oxidative damage, affecting the normal life process of cells, and finally promoting the process of ferroptosis. The regulation of ferroptosis is closely related to the normal physiological process of cells, and it involves iron metabolism, lipid metabolism, and the balance between oxygen-free radical reaction and lipid peroxidation. A large number of studies have confirmed that ferroptosis is a result of the combined action of the cellular oxidation/antioxidant system and cell membrane damage/repair, which has great potential application in tumor therapy. Therefore, this review aims to explore potential therapeutic targets for ferroptosis in lung cancer by clarifying the regulatory pathway of ferroptosis. Based on the study of ferroptosis, the regulation mechanism of ferroptosis in lung cancer was understood and the existing chemical drugs and natural compounds targeting ferroptosis in lung cancer were summarized, with the aim of providing new ideas for the treatment of lung cancer. In addition, it also provides the basis for the discovery and clinical application of chemical drugs and natural compounds targeting ferroptosis to effectively treat lung cancer.

Long noncoding RNAs induced control of ferroptosis: Implications in cancer progression and treatment

A novel kind of nonapoptotic, iron-dependent cell death brought on by lipid peroxidation is known as ferroptosis. Numerous pathological processes, including neurotoxicity, neurological disorders, ischemia-reperfusion damage, and particularly cancer, have been demonstrated to be influenced by changes in the ferroptosis-regulating network. Recent studies have established the critical roles that ferroptosis can play in cancer development and the evolution of resistance to standard chemoradiotherapy, thus suggesting that ferroptosis may be a feasible therapeutic strategy for cancer management. Gene expression may be regulated at the transcriptional and posttranscriptional levels by long noncoding RNAs (lncRNAs). They have been implicated in tumorigenesis. Some lncRNAs participate in the biological process of ferroptosis, which represents an exciting alternative to regulate ferroptosis as a means of cancer therapy. Even though there is evidence that lncRNAs have a mechanistic role in the ferroptosis of cancer cells, research on the mechanism and potential treatments for these lncRNAs is still lacking. We elucidate the potential mechanisms by which lncRNAs modulate ferroptosis in cancer and examine the promise and challenges of employing lncRNAs as novel therapeutic targets in cancer.

Development and validation of a novel ferroptosis‑related lncRNA prognostic signature for pancreatic adenocarcinoma

Long non‑coding RNAs (lncRNAs) serve a pivotal role in the regulation of cancer cell ferroptosis. However, the prognostic value of ferroptosis‑related lncRNAs in pancreatic adenocarcinoma (PAAD) largely remains unclear. We aimed at constructing a lncRNA‑based signature to improve the prognosis prediction of PAAD. In the present study, the transcriptome profiling data and clinical information of patients with PAAD were obtained from The Cancer Genome Atlas (TCGA) and International Cancer Gene Consortium (ICGC) databases. Univariate Cox regression analysis of the TCGA cohort demonstrated that 26 ferroptosis‑related lncRNAs had significant prognostic value for PAAD (all P<0.01). Least absolute shrinkage and selection operator regression and multivariate Cox proportional hazards regression analyses were performed to construct a prognostic ferroptosis‑related lncRNA signature (FRLS) comprising nine ferroptosis‑related lncRNAs. The efficacy of this FRLS was verified in the training (TCGA) and validation (ICGC) cohorts. Based on the risk model, high risk scores were significantly correlated with poor overall survival (OS) (hazard ratio, 1.314; 95% confidence interval, 1.218‑1.418; P<0.001). The receiver operating characteristic curves and principal component analysis further demonstrated the robust prognostic ability of the FRLS. Furthermore, a nomogram with favorable predictive efficacy for the prediction of OS was constructed based on the FRLS and clinical features. Gene set enrichment analysis demonstrated that the genes in the FRLS participated in a number of cancer‑associated immunoregulatory pathways. Importantly, it was demonstrated that immune infiltration and response to cancer immunotherapy differed significantly between the high and low‑risk groups according to the FRLS. In conclusion, the risk signature based on the FRLS has potential for the clinical prediction of prognosis and immunotherapy response in patients with PAAD.

LncRNAs has been identified as regulators of Myeloid-derived suppressor cells in lung cancer

Lung tumours are widespread pathological conditions that attract much attention due to their high incidence of death. The immune system contributes to the progression of these diseases, especially non-small cell lung cancer, resulting in the fast evolution of immune-targeted therapy. Myeloid-derived suppressor cells (MDSCs) have been suggested to promote the progression of cancer in the lungs by suppressing the immune response through various mechanisms. Herein, we summarized the clinical studies on lung cancer related to MDSCs. However, it is noteworthy to mention the discovery of long non-coding RNAs (lncRNAs) that had different phenotypes and could regulate MDSCs in lung cancer. Therefore, by reviewing the different phenotypes of lncRNAs and their regulation on MDSCs, we summarized the lncRNAs' impact on the progression of lung tumours. Data highlight LncRNAs as anti-cancer agents. Hence, we aim to discuss their possibilities to inhibit tumour growth and trigger the development of immunosuppressive factors such as MDSCs in lung cancer through the regulation of lncRNAs. The ultimate purpose is to propose novel and efficient therapy methods for curing patients with lung tumours.

Recent progress in ferroptosis: inducers and inhibitors

Ferroptosis is a new iron-dependent form of programmed cell death characterized by iron accumulation and lipid peroxidation. In recent years, ferroptosis has garnered enormous interest in disease treatment research communities in pursuit to reveal the mechanism and key targets of ferroptosis because ferroptosis is closely related to the pathophysiological processes of many diseases. Recent studies have shown some key targets, such as glutathione peroxidase 4 (GPX4) and System Xc^-, and several inducers and inhibitors have been developed to regulate these key targets. With the emergence of new ferroptosis targets, studies on inducers and inhibitors have made new developments. The selection and use of inducers and inhibitors are very important for related work. This paper briefly introduces important regulatory targets in the ferroptosis metabolic pathway, lists and categorizes commonly used and recently developed inducers and inhibitors, and discusses their medical application. The paper ends of with potential future research direction for ferroptosis.

A stratification system of ferroptosis and iron-metabolism related LncRNAs guides the prediction of the survival of patients with esophageal squamous cell carcinoma

Ferroptosis and iron-metabolism have been widely reported to play an important role in cancer. Long non-coding RNAs (lncRNAs) are increasingly recognized as the crucial mediators in the regulation of ferroptosis and iron metabolism. A systematic understanding of ferroptosis and iron-metabolism related lncRNAs (FIRLs) in esophageal squamous cell carcinoma (ESCC) is essential for prognosis prediction. Herein, Pearson’s correlation analysis was carried out between ferroptosis and iron-metabolism-related genes (FIRGs) and all lncRNAs to derive the FIRLs. Based on weighted gene co-expression network exploration (WCGNA), least absolute shrinkage and selection operator (LASSO) regression and Cox regression analysis, a risk stratification system, including 3 FIRLs (LINC01068, TMEM92-AS1, AC243967.2), was established. According to Kaplan-Meier analysis, receiver operating characteristic (ROC) curve analysis, and univariate and multivariate Cox regression analyses, the risk stratification system had excellent predictive ability and clinical relevance. The validity of the established prognostic signature was further examined in TCGA (training set) and GEO (validation set) cohorts. A nomogram with enhanced precision for forecasting OS was set up on basis of the independent prognostic elements. Functional enrichment analysis revealed that three FIRLs took part in various cellular functions and signaling pathways, and the immune status was varied in the high-risk and low-risk groups. In the end, the oncogenic effects of LINC01068 was explored using in vitro researches. Overall, a risk stratification system of three FIRLs was found to have significant prognostic value for ESCC and may serve as a ferroptosis-associated therapeutic target in the clinic.

Screening of potential key ferroptosis-related genes in sepsis

Background

Sepsis leads to multiple organ dysfunction caused by a dysregulated host response to infection with a high incidence and mortality. The effect of ferroptosis on the development of sepsis remains unclear. In this study, we aimed to identify the key ferroptosis-related genes involved in sepsis and further explore the potential biological functions of these ferroptosis-related genes in sepsis using bioinformatics analysis.

Methods

The GSE13904 (from children) and GSE28750 (from adults) datasets were downloaded from the Gene Expression Omnibus (GEO). The ferroptosis-related genes were obtained from the FerrDb database. The ferroptosis-related differentially expressed genes (DEGs) were screened by the limma R package. The DAVID online database or clusterProfiler R package was used for the functional enrichment analysis. Then, the STRING database was used to predict the interactions of proteins, and the CytoHubba plugin of Cytoscape was used to confirm key clustering modules. Then, the miRNAs and lncRNAs associated with the key clustering modules were predicted by miRWalk 2.0 and LncBase v.2 respectively. Finally, we generated a cecal ligation and puncture (CLP) polymicrobial sepsis model in C57 male mice and examined the expression of the mRNAs and noncoding RNAs of interest in peripheral blood leukocytes by PCR during the acute inflammation phase.

Results

In total, 34 ferroptosis-related DEGs were identified in both adult and pediatric septic patients. These ferroptosis-related DEGs were mainly enriched in inflammatory pathways. Then, a significant clustering module containing eight genes was identified. Among them, the following five genes were closely associated with the MAPK signaling pathway: MAPK14, MAPK8, DUSP1, MAP3K5 and MAPK1. Then, crucial miRNAs and lncRNAs associated with biomarker MAPK-related genes were also identified. In particular, let-7b-5p and NEAT1 were selected as noncoding RNAs of interest because of their correlation with ferroptosis in previous studies. Finally, we examined the mRNAs, miRNAs and lncRNAs of interest using CLP-induced sepsis in peripheral blood leukocytes of mice. The results showed that MAPK14, MAPK8, MAP3K5, MAPK1 and NEAT1 were upregulated, while DUSP1 and let-7b-5p were downregulated in the CLP group compared with the sham group.

Conclusions

The MAPK signaling pathway may play a key role in regulating ferroptosis during sepsis. This study provides a valuable resource for future studies investigating the mechanism of MAPK-related ferroptosis in sepsis.

ACSL4 as a Potential Target and Biomarker for Anticancer: From Molecular Mechanisms to Clinical Therapeutics

Cancer is a major public health problem around the world and the key leading cause of death in the world. It is well-known that glucolipid metabolism, immunoreaction, and growth/death pattern of cancer cells are markedly different from normal cells. Recently, acyl-CoA synthetase long-chain family 4 (ACSL4) is found be participated in the activation of long chain fatty acids metabolism, immune signaling transduction, and ferroptosis, which can be a promising potential target and biomarker for anticancer. Specifically, ACSL4 inhibits the progress of lung cancer, estrogen receptor (ER) positive breast cancer, cervical cancer and the up-regulation of ACSL4 can improve the sensitivity of cancer cells to ferroptosis by enhancing the accumulation of lipid peroxidation products and lethal reactive oxygen species (ROS). However, it is undeniable that the high expression of ACSL4 in ER negative breast cancer, hepatocellular carcinoma, colorectal cancer, and prostate cancer can also be related with tumor cell proliferation, migration, and invasion. In the present review, we provide an update on understanding the controversial roles of ACSL4 in different cancer cells.

Silenced LINC01134 Enhances Oxaliplatin Sensitivity by Facilitating Ferroptosis Through GPX4 in Hepatocarcinoma

Purpose

Recently, long noncoding RNA LINC01134 has been shown to reduce cell viability and apoptosis via the antioxidant stress pathway, thereby enhancing OXA resistance in hepatocellular carcinoma. However, the association of LINC01134 with ferroptosis and the underlying molecular mechanisms remain to be elucidated.

Methods

Bioinformatics analysis was employed to screen lncRNAs positively correlated with GPX4 and poor clinical prognosis. And Western blot and RT-PCR analysis in HCC cells confirmed the effect of LINC01134 on GPX4 expression. In addition, LINC01134 siRNA was transfected in HCC cells to detect the changes in cell viability, ROS, lipid peroxidation, MDA levels and GSH/GSSG levels. CCK-8, colony formation and apoptosis assays were performed to determine the effect of LINC01134 on cell death. The effect of LINC01134 and OXA on Nrf2 transcriptional binding to GPX4 was analyzed using dual luciferase reporter assay and CHIP. The expression of GPX4 and Nrf2 in HCC tissues was detected by FISH and IHC.

Results

LINC01134 is a novel lncRNA positively correlated with GPx4 and associated with poor clinical prognosis. Silenced LINC01134 conferred OXA sensitivity by enhancing total ROS, lipid ROS, MDA levels and decreasing GSH/GSSG ratio. Mechanistically, LINC01134 and OXA could promote Nrf2 recruitment to the GPX4 promoter region to exert transcriptional regulation of GPX4. Clinically, LINC01134 was positively correlated with GPX4 or Nrf2, demonstrating the clinical significance of LINC01134, Nrf2 and GPX4 in OXA resistance of HCC.

Conclusions

We identified LINC01134/Nrf2/GPX4 as a novel and critical axis to regulate HCC growth and progression. Targeting GPX4, knocking down LINC01134 or Nrf2 could be a potential therapeutic strategy for HCC.

Comprehensive Analysis of a Ferroptosis-Related lncRNA Signature for Predicting Prognosis and Immune Landscape in Osteosarcoma

Research on the implications of ferroptosis in tumors has increased rapidly in the last decades. There are evidences that ferroptosis is involved in several aspects of cancer biology, including tumor progression, metastasis, immunomodulation, and therapeutic response. Nonetheless, the interaction between ferroptosis-related lncRNAs (FRLs) and the osteosarcoma immune microenvironment is poorly understood. In this study, a risk model composed of FRLs was developed using univariate and LASSO Cox regression analyses. On the basis of this model, FRL scores were calculated to systematically explore the role of the model in predicting the prognosis and immune characteristics of osteosarcoma patients. Survival analysis showed that osteosarcoma samples with lower FRL-score had better overall survival. After predicting the abundance of immune cells in osteosarcoma microenvironment by single-sample gene-set enrichment analysis (ssGSEA) and ESTIMATE analysis, we found that the FRL-score could distinguish immune function, immune score, stromal score, tumor purity, and tumor infiltration of immune cells in different osteosarcoma patients. In addition, FRL-score was also associated with immune checkpoint gene expression and half-maximal inhibitory concentration of chemotherapeutic agents. Finally, we confirmed that knockdown of RPARP-AS1 suppressed the malignant activity of osteosarcoma cells in vitro experiments. In general, the FRL-based prognostic signature could promote our understanding of the immune microenvironment characteristics of osteosarcoma and guide more effective treatment regimens.

Ferroptosis-Related Long Noncoding RNAs as Prognostic Biomarkers for Ovarian Cancer

Ovarian cancer (OC) is a highly malignant gynecologic tumor with few treatments available and poor prognosis with the currently available diagnostic markers and interventions. More effective methods for diagnosis and treatment are urgently needed. Although the current evidence implicates ferroptosis in the development and therapeutic responses of various types of tumors, it is unclear to what extent ferroptosis affects OC. To explore the potential of ferroptosis-related genes as biomarkers and molecular targets for OC diagnosis and intervention, this study collected several datasets from The Cancer Genome Atlas-OC (TCGA-OC), analyzed and identified the coexpression profiles of 60 ferroptosis-related genes and two subtypes of OC with respect to ferroptosis and further examined and analyzed the differentially expressed genes between the two subtypes. The results indicated that the expression levels of ferroptosis genes were significantly correlated with prognosis in patients with OC. Single-factor Cox and LASSO analysis identified eight lncRNAs from the screened ferroptosis-related genes, including lncRNAs RP11-443B7.3, RP5-1028K7.2, TRAM2-AS1, AC073283.4, RP11-486G15.2, RP11-95H3.1, RP11-958F21.1, and AC006129.1. A risk scoring model was constructed from the ferroptosis-related lncRNAs and showed good performance in the evaluation of OC patient prognosis. The high- and low-risk groups based on tumor scores presented obvious differences in clinical characteristics, tumor mutation burden, and tumor immune cell infiltration, indicating that the risk score has a good ability to predict the benefit of immunotherapy and may provide data to support the implementation of precise immunotherapy for OC. Although in vivo tests and research are needed in the future, our bioinformatics analysis powerfully supported the effectiveness of the risk signature of ferroptosis-related lncRNAs for prognosis prediction in OC. The findings suggest that these eight identified lncRNAs have great potential for development as diagnostic markers and intervention targets for OC and that patients with high ferroptosis-related lncRNA expression will receive greater benefits from conventional chemotherapy or treatment with ferroptosis inducers.

The Organelle-Specific Regulations and Epigenetic Regulators in Ferroptosis

Ferroptosis is fairly different from other types of cell-death in biochemical processes, morphological changes and genetics as a special programmed cell-death. Here we summarize the current literatures on ferroptosis, including the cascade reaction of key material metabolism in the process, dysfunction of organelles, the relationship between different organelles and the way positive and negative key regulatory factors to affect ferroptosis in the epigenetic level. Based on material metabolism or epigenetic regulation, it is obvious that the regulatory network of ferroptosis is interrelated and complex.

Non-coding RNAs and ferroptosis: potential implications for cancer therapy

Ferroptosis is a recently defined form of regulated cell death, which is biochemically and morphologically distinct from traditional forms of programmed cell death such as apoptosis or necrosis. It is driven by iron, reactive oxygen species, and phospholipids that are oxidatively damaged, ultimately resulting in mitochondrial damage and breakdown of membrane integrity. Numerous cellular signaling pathways and molecules are involved in the regulation of ferroptosis, including enzymes that control the cellular redox status. Alterations in the ferroptosis-regulating network can contribute to the development of various diseases, including cancer. Evidence suggests that ferroptosis is commonly suppressed in cancer cells, allowing them to survive and progress. However, cancer cells which are resistant to common chemotherapeutic drugs seem to be highly susceptible to ferroptosis inducers, highlighting the great potential of pharmacologic modulation of ferroptosis for cancer treatment. Non-coding RNAs (ncRNAs) are considered master regulators of various cellular processes, particularly in cancer where they have been implicated in all hallmarks of cancer. Recent work also demonstrated their involvement in the molecular control of ferroptosis. Hence, ncRNA-based therapeutics represent an exciting alternative to modulate ferroptosis for cancer therapy. This review summarizes the ncRNAs implicated in the regulation of ferroptosis in cancer and highlights their underlying molecular mechanisms in the light of potential therapeutic applications.

Stressing the Regulatory Role of Long Non-Coding RNA in the Cellular Stress Response during Cancer Progression and Therapy

Cellular stress response is an important adaptive mechanism for regulating cell fate decision when cells confront with stress. During tumorigenesis, tumor progression and the course of treatment, cellular stress signaling can activate subsequent response to deal with stress. Therefore, cellular stress response has impacts on the fate of tumor cells and tumor responsiveness relative to therapeutic agents. In recent years, attention has been drawn to long non-coding RNAs (lncRNAs), a novel class of RNA molecules with more than 200 nucleotides in length, which has little protein-coding potential and possesses various functions in multiple biological processes. Accumulating evidence has shown that lncRNAs are also engaged in the regulation of cellular stress response, particularly in cancers. Here, we summarize lncRNAs that have been reported in the adaptive response to major types of cellular stress including genotoxic, hypoxic, oxidative, metabolic and endoplasmic reticulum stress, all of which are often encountered by cancer cells. Specifically, the molecular mechanisms of how lncRNAs regulate cellular stress response during tumor progression or the development of therapy resistance are emphasized. The potential clinical applications of stress-responsive lncRNAs as biomarkers will also be discussed.

Non-coding RNAs in ferroptotic cancer cell death pathway: meet the new masters

Despite the recent advances in cancer therapy, cancer chemoresistance looms large along with radioresistance, a major challenge in dire need of thorough and minute investigation. Not long ago, cancer cells were reported to have proven refractory to the ferroptotic cell death, a newly discovered form of regulated cell death (RCD), conspicuous enough to draw attention from scholars in terms of targeting ferroptosis as a prospective therapeutic strategy. However, our knowledge concerning the underlying molecular mechanisms through which cancer cells gain immunity against ferroptosis is still in its infancy. Of late, the implication of non-coding RNAs (ncRNAs), including circular RNAs (circRNAs), microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) in ferroptosis has been disclosed. Nevertheless, precisely explaining the molecular mechanisms behind the contribution of ncRNAs to cancer radio/chemotherapy resistance remains a challenge, requiring further clarification. In this review, we have presented the latest available information on the ways and means of regulating ferroptosis by ncRNAs. Moreover, we have provided important insights about targeting ncRNAs implicated in ferroptosis with the hope of opening up new horizons for overcoming cancer treatment modalities. Though a long path awaits until we make this ambitious dream come true, recent progress in gene therapy, including gene-editing technology will aid us to be optimistic that ncRNAs-based ferroptosis targeting would soon be on stream as a novel therapeutic strategy for treating cancer.

Targeting lncRNAs in programmed cell death as a therapeutic strategy for non-small cell lung cancer

Lung cancer is a leading cause of cancer-related mortality worldwide, with non-small cell lung cancer (NSCLC) being the most common histological type. Owing to the limited therapeutic efficacy and side effects of currently available therapies for NSCLC, it is necessary to identify novel therapeutic targets for NSCLC. Long non-coding RNAs (lncRNAs) are non-protein-coding RNAs with a transcript length of more than 200 nucleotides, which play a vital role in the tumorigenesis and progression of multiple cancers, including NSCLC. Induction of programmed cell death (PCD) is the main mechanism leading to tumour cell death in most cancer treatments. Recent studies have demonstrated that lncRNAs are closely correlated with PCD including apoptosis, pyroptosis, autophagy and ferroptosis, which can regulate PCD and relevant death pathways to affect NSCLC progression and the efficacy of clinical therapy. Therefore, in this review, we focused on the function of lncRNAs in PCD of NSCLC and summarized the therapeutic role of targeting lncRNAs in PCD for NSCLC treatment, aiming to provide new sights into the underlying pathogenic mechanisms and propose a potential new strategy for NSCLC therapy so as to improve therapeutic outcomes with the ultimate goal to benefit the patients.

Identification and Validation of a Ferroptosis-Related Long Non-Coding RNA (FRlncRNA) Signature to Predict Survival Outcomes and the Immune Microenvironment in Patients With Clear Cell Renal Cell Carcinoma

Background: The incidence of clear cell renal cell carcinoma (ccRCC) is increasing worldwide, contributing to 70–85% of kidney cancer cases. Ferroptosis is a novel type of programmed cell death and could predict prognoses in cancers. Here, we developed a ferroptosis-related long non-coding RNA (FRlncRNA) signature to improve the prognostic prediction of ccRCC.

Methods: The transcriptome profiles of FRlncRNAs and clinical data of ccRCC were obtained from The Cancer Genome Atlas and ICGC databases. Patients were randomly assigned to training cohorts, testing cohorts, and overall cohorts. The FRlncRNA signature was constructed by Lasso regression and Cox regression analysis, and Kaplan–Meier (K-M) analysis was used to access the prognosis of each group. The accuracy of this signature was evaluated by the receiver operating characteristic (ROC) curve. The visualization of functional enrichment was carried out by the gene set enrichment analysis (GSEA). Internal and external datasets were performed to verify the FRlncRNA signature.

Results: A FRlncRNA signature comprising eight lncRNAs (AL590094.1, LINC00460, LINC00944, AC024060.1, HOXB-AS4, LINC01615, EPB41L4A-DT, and LINC01550) was identified. Patients were divided into low- and high-risk groups according to the median risk score, in which the high-risk group owned a dramatical shorter survival time than that of the low-risk group. Through ROC analysis, it was found that this signature had a greater predictive capability than traditional evaluation methods. The risk score was an independent risk factor for overall survival suggested by multivariate Cox analysis (HR = 1.065, 95%CI = 1.036–1.095, and p < 0.001). We constructed a clinically predictive nomogram based on this signature and its clinical features, which is of accurate prediction about the survival rate of patients. The GSEA showed that primary pathways were the P53 signaling pathway and tumor necrosis factor–mediated signaling pathway. The major FRlncRNAs (LINC00460, LINC00944, LINC01550, and EPB41L4A-DT) were verified with the prognosis of ccRCC in the GEPIA and K-M Plotter databases. Their major target genes (BNIP3, RRM2, and GOT1) were closely related to the stage, grade, and survival outcomes of ccRCC by the validation of multiple databases. Additionally, we found two groups had a significant distinct pattern of immune function, immune checkpoint, and immune infiltration, which may lead to different survival benefits.

Conclusions: The FRlncRNA signature was accurate and act as reliable tools for predicting clinical outcomes and the immune microenvironment of patients with ccRCC, which may be molecular biomarkers and therapeutic targets.

Identification of Ferroptosis-Related Biomarkers for Prognosis and Immunotherapy in Patients With Glioma

Ferroptosis is a novel type of iron- and ROS-dependent cell death and is involved in various diseases. LncRNAs are involved and play important roles in the occurrence and development of several cancers. However, researches about the role of ferroptosis-related lncRNAs in glioma are relatively rare. Here, we identified nine ferroptosis-related lncRNAs and then constructed a prognostic model by the LASSO and Cox analysis. The model could predict overall survival with high sensitivity and specificity according to ROC curves. In addition, the cell cycle, p53 signaling, apoptosis, and oxidative phosphorylation pathways were obviously enriched in the pathogenesis of glioma by gene set enrichment analysis. A nomogram was constructed by integrating several independent prognostic clinicopathological features, and it could provide a valuable predictive tool for overall survival. Furthermore, a strong correlation between these nine lncRNAs and immunotherapy was found. Glioma patients in the high-risk group had higher TMB using somatic mutation data, different immune infiltration, and higher expression of immune checkpoints, indicating these patients might benefit from immune checkpoint inhibitor therapy. In summary, these nine ferroptosis-related lncRNAs were promising biomarkers for predicting overall survival and guiding immunotherapy or future immune checkpoint inhibitor development for glioma patients.

Risk stratification of lung adenocarcinoma using a nomogram combined with ferroptosis-related LncRNAs and subgroup analysis with immune and N6-methyladenosine modification

Background

Determining the prognosis of lung adenocarcinoma (LUAD) is challenging. The present study aimed to identify prognostic ferroptosis-related long noncoding RNAs (FRLs) and construct a prognostic model. Moreover, differential analysis of immune and N6-methyladenosine (m6A)-related genes was systematically conducted.

Methods

A total of 504 patients selected from a dataset from The Cancer Genome Atlas were included. The patients with LUAD were randomly divided into a training group and a test group at a ratio of 1:1. Pearson correlation analysis and univariate Cox regression analysis were used to identify the prognostic FRLs. Then, a prognostic model was constructed from the optimized subset of prognostic FRLs based on the least absolute shrinkage and selection operator (LASSO) algorithm. Subsequently, the receiver operating characteristic (ROC) curve and survival analysis were used to evaluate the performance of the model. The risk score based on the prognostic model was analyzed using Cox regression analysis. Moreover, gene set enrichment analysis and differential analysis of immune- and m6A-related genes were conducted.

Results

After univariate Cox regression analysis and LASSO algorithm analysis, a total of 19 prognostic FRLs were selected to construct the final model to obtain the risk score. The area under the ROC curve of the prognostic model for 1-year, 3-year, and 5-year overall survival (OS) was 0.763, 0.745, and 0.778 in the training set and 0.716, 0.724, and 0.736 in the validation set, respectively. Moreover, the OS of the high-risk group was significantly worse than that of the low-risk group in the training group (P < 0.001) and in the test group (P < 0.001). After univariate and multivariate Cox regression analysis, the risk score [hazard ratio (HR) = 1.734; P < 0.001] and stage (HR = 1.557; P < 0.001) were both considered significant prognostic factors for LUAD. A nomogram was constructed based on clinical features and risk score. The expression of 34 checkpoint genes and 13 m6A-related genes varied significantly between the two risk groups.

Conclusion

This study constructed a prognostic model to effectively predict the OS of patients with LUAD, and these OS-related FRLs might serve as potential therapeutic targets of LUAD.

Bioinformatic Analyses of the Ferroptosis-Related lncRNAs Signature for Ovarian Cancer

Both ferroptosis and lncRNAs are significant for ovarian cancer (OC). Whereas, the study of ferroptosis-related lncRNAs (FRLs) still few in ovarian cancer. We first constructed an FRL-signature for patients with OC in the study. A total of 548 FRLs were identified for univariate Cox regression analysis, and 21 FRLs with significant prognosis were identified. The prognostic characteristics of nine FRLs was constructed and validated, showing opposite prognosis in two subgroups based on risk scores. The multivariate Cox regression analysis and nomogram further verified the prognostic value of the risk model. By calculating ferroptosis score through ssGSEA, we found that patients with higher risk scores exhibited higher ferroptosis scores, and high ferroptosis score was a risk factor. There were 40 microenvironment cells with significant differences in the two groups, and the difference of Stromal score between the two groups was statistically significant. Six immune checkpoint genes were expressed at different levels in the two groups. In addition, five m6A regulators (FMR1, HNRNPC, METTL16, METTL3, and METTL5) were higher expressed in the low-risk group. GSEA revealed that the risk model was associated with tumor-related pathways and immune-associated pathway. We compared the sensitivity of chemotherapy drugs between the two risk groups. We also explored the co-expression, ceRNA relation, cis and trans interaction of ferroptosis-related genes and lncRNAs, providing a new idea for the regulatory mechanisms of FRLs. Moreover, the nine FRLs were selected for detecting their expression levels in OC cells and tissues.

Exosome-Derived lncRNA NEAT1 Exacerbates Sepsis-Associated Encephalopathy by Promoting Ferroptosis Through Regulating miR-9-5p/TFRC and GOT1 Axis

Sepsis can cause sepsis-associated encephalopathy (SAE), but whether SAE was induced or exacerbated by ferroptosis remains unknown. In this study, the rat sepsis model was constructed using the cecal ligation and puncture method. The blood–brain barrier (BBB) permeability was measured by Evans blue dye (EBD) in vivo. The levels of ROS, Fe ion, MDA, GSH, and GPX4 were assessed by enzyme-linked immunosorbent assay (ELISA). The exosomes isolated from serum were cultured with bEnd.3 cells for the in vitro analysis. Moreover, bEnd.3 cells cultured with 100 μM FeCl3 (iron-rich) were to simulate ferroptosis stress. The cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay. A dual-luciferase reporter gene assay was performed to confirm the relationship between miR-9-5p with NEAT1, TFRC, and GOT1. In vivo, it is found that BBB permeability was damaged in model rats. Level of ROS, Fe ion, and MDA was increased, and level of GSH and GPX4 was decreased, which means ferroptosis was induced by sepsis. Exosome-packaged NEAT1 in serum was significantly upregulated in model rats. In vitro, it is found that NEAT1 functions as a ceRNA for miR-9-5p to facilitate TFRC and GOT1 expression. Overexpression of NEAT1 enhanced ferroptosis stress in bEnd.3 cells. Increased miR-9-5p alleviated sepsis-induced ferroptosis by suppressing the expression of TFRC and GOT1 both in vivo and in vitro. In conclusion, these findings suggest that sepsis induced high expression of serous exosome-derived NEAT1, and it might exacerbate SAE by promoting ferroptosis through regulating miR-9-5p/TFRC and GOT1 axis.

Ferroptosis in Lung Cancer: From Molecular Mechanisms to Prognostic and Therapeutic Opportunities

Lung cancer is the second commonly diagnosed malignancy worldwide and has the highest mortality rate among all cancers. Tremendous efforts have been made to develop novel strategies against lung cancer; however, the overall survival of patients still is low. Uncovering underlying molecular mechanisms of this disease can open up new horizons for its treatment. Ferroptosis is a newly discovered type of programmed cell death that, in an iron-dependent manner, peroxidizes unsaturated phospholipids and results in the accumulation of radical oxygen species. Subsequent oxidative damage caused by ferroptosis contributes to cell death in tumor cells. Therefore, understanding its molecular mechanisms in lung cancer appears as a promising strategy to induce ferroptosis selectively. According to evidence published up to now, significant numbers of research have been done to identify ferroptosis regulators in lung cancer. Therefore, this review aims to provide a comprehensive standpoint of molecular mechanisms of ferroptosis in lung cancer and address these molecules’ prognostic and therapeutic values, hoping that the road for future studies in this field will be paved more efficiently.

Ferroptosis in Non-Small Cell Lung Cancer: Progression and Therapeutic Potential on It

As a main subtype of lung cancer, the current situation of non-small cell lung cancer (NSCLC) remains severe worldwide with a 19% survival rate at 5 years. As the conventional therapy approaches, such as chemotherapy, radiotherapy, targeted therapy, and immunotherapy, gradually develop into therapy resistance, searching for a novel therapeutic strategy for NSCLC is urgent. Ferroptosis, an iron-dependent programmed necrosis, has now been widely considered as a key factor affecting the tumorigenesis and progression in various cancers. Focusing on its effect in NSCLC, in different situations, ferroptosis can be triggered or restrained. When ferroptosis was induced in NSCLC, it was available to inhibit the tumor progression both in vitro and in vivo. The dominating mechanism was due to a regulation of the classic ferroptosis-repressed GSH-dependent GPX4 signaling pathway instead of other fractional regulating signal axes that regulated ferroptosis via impacting on the ROS, cellular iron levels, etc. In terms of the prevention of ferroptosis in NSCLC, an GSH-independent mechanism was also discovered, interestingly exhibiting the same upstream as the GPX4 signaling. In addition, this review summarizes the progression of ferroptosis in NSCLC and elaborates their association and specific mechanisms through bioinformatics analysis with multiple experimental evidence from different cascades. Finally, this review also points out the possibility of ferroptosis working as a novel strategy for therapy resistance in NSCLC, emphasizing its therapeutic potential.

Caveolin-1 promotes cancer progression via inhibiting ferroptosis in head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) is an aggressive disease worldwide. Much progress has been made in exploring mechanisms and improving the therapy of HNSCC, but only a few studies have focused on the role of ferroptosis on HNSCC progression. The current study aimed to reveal the underlining mechanisms that caveolin‐1 (CAV1)‐ROS (reactive oxygen species)‐ferroptosis axis affect the process of HNSCC and discover novo therapeutic targets or strategies.

Methods

The role of CAV1 in ferroptosis was analyzed by FerrDb, and its clinical significance was examined by TCGA dataset of HNSCC. The expressions of caveolin‐1 (CAV1) in HNSCC tissues were measured by immunohistochemistry, western blot, and real‐time PCR assay. Three siRNA sequences were designed to silence CAV1 mRNA in HNSCC cells. Cell proliferation, colony formation, wound‐healing, and transwell assays were used to examine the proliferation, migration, and invasion of cancer cells. ROS evaluation and intracellular Fe²⁺ content assays were performed to examine the levels of ferroptosis.

Results

Through the analysis with published data, CAV1 was found to overexpress in HNSCC than normal tissues, and was one of the vital suppressors of ferroptosis pathway. Our study showed that CAV1 was over expressed in HNSCC tissues and the high level of CAV1 predicted poorer prognosis. Further experiments indicated that CAV1 could inhibit the ferroptosis of cancer cells and promote the proliferation, migration and invasion.

Conclusions

Overexpression of CAV1 in HNSCC inhibited the process of ferroptosis, leading to aggressive phenotypes, as well as worse prognosis. The regulatory pathway of CAV1 and ferroptosis are potential targets for designing diagnostic and combined therapeutic strategies for HNSCC patients.

Close interactions between lncRNAs, lipid metabolism and ferroptosis in cancer

Abnormal lipid metabolism including synthesis, uptake, modification, degradation and transport has been considered a hallmark of malignant tumors and contributes to the supply of substances and energy for rapid cell growth. Meanwhile, abnormal lipid metabolism is also associated with lipid peroxidation, which plays an important role in a newly discovered type of regulated cell death termed ferroptosis. Long noncoding RNAs (lncRNAs) have been proven to be associated with the occurrence and progression of cancer. Growing evidence indicates that lncRNAs are key regulators of abnormal lipid metabolism and ferroptosis in cancer. In this review, we mainly summarized the mechanism by which lncRNAs regulate aberrant lipid metabolism in cancer, illustrated that lipid metabolism can also influence the expression of lncRNAs, and discussed the mechanism by which lncRNAs affect ferroptosis. A comprehensive understanding of the interactions between lncRNAs, lipid metabolism and ferroptosis could help us to develop novel strategies for precise cancer treatment in the future.

The role of ferroptosis in lung cancer

Lung cancer is one of the most common cancers in the world. Although medical treatment has made impressive progress in recent years, it is still one of the leading causes of cancer-related deaths in men and women. Ferroptosis is a type of non-apoptotic cell death modality, usually characterized by iron-dependent lipid peroxidation, rather than caspase-induced protein cleavage. Excessive or lack of ferroptosis is associated with a variety of diseases, including cancer and ischaemia-reperfusion injury. Recent preclinical evidence suggests that targeting ferroptotic pathway is a potential strategy for the treatment of lung cancer. In this review, we summarize the core mechanism and regulatory network of ferroptosis in lung cancer cells, and highlight ferroptosis induction-related tumor therapies. The reviewed information may provide new insights for targeted lung cancer therapy.

A ferroptosis-related lncRNA signature predicts prognosis in ovarian cancer patients

Background

Ovarian cancer (OC) is a common gynecological malignant tumor with poor prognosis. Ferroptosis is an iron-dependent modality of regulated cell death. The purpose of this study was to determine the prognostic ability of ferroptosis-related long non-coding RNAs (lncRNAs) in OC patients and construct a ferroptosis-related lncRNA prognostic model.

Methods

The Cancer Genome Atlas (TCGA) and FerrDb databases were used to collect RNA sequencing data of OC patients and ferroptosis-related genes, respectively. OC patients were randomly assigned to the training or testing set. Pearson correlation analysis was used to identify ferroptosis-related lncRNAs. Univariate Cox, Least Absolute Shrinkage and Selection Operator (LASSO), and multivariate regression analyses were performed in the training set to develop a predictive model. The model was validated in the testing set and entire set. Survival analysis, receiver operating characteristic curves, independent prognostic factor analysis, and correlation analysis with clinical features were performed to evaluate the predictive value of the model. A nomogram was established to predict the survivability of OC patients over 1, 3, and 5 years. The distribution of distinct groups was investigated using principal component analysis, and the underlying the biological functions were explored using gene set enrichment analysis.

Results

Eleven ferroptosis-related lncRNAs were determined to establish the prognostic model. Patients in the high-risk group had poor prognosis compared with the low-risk group in the training, testing and entire sets. The area under the receiver operating characteristic curve corresponding to 1-, 3-, and 5-year survival were 0.731, 0.796, and 0.805 in the training set; 0.704, 0.597, and 0.655 in the testing set; and 0.715, 0.691, and 0.736, in the entire set, respectively. The risk score correlated with age and grade. The risk score was also an independent prognostic factor in OC. A nomogram with high C-index (0.68) was constructed. An intuitive observation of the principal component analysis revealed a distinction between high- and low-risk groups, and gene set enrichment analysis indicated that cancer-related pathways were enriched in the high-risk group.

Conclusions

The signature composed of 11 ferroptosis-related lncRNAs accurately predicted the prognosis of OC patients.

ASMTL-AS1 impedes the malignant progression of lung adenocarcinoma by regulating SAT1 to promote ferroptosis

Lung adenocarcinoma (LUAD) is difficult to cureradically. Long non-coding RNAs (lncRNAs) in LUAD are a hotspot in molecular research, however, the role of lncRNA ASMTL-AS1 in LUAD is still unknown. Our study explores the role and mechanisms of ASMTL-AS1 in LUAD. Quantitative reverse transcription PCR or western blot was utilized to analyze the expression of RNAs or proteins. The influences of ASMTL-AS1 and SAT1 on LUAD cells were analyzed by functional assays. Biological instruments were applied to observe ferroptosis-related markers. In vivo assays were performed to uncover the impact of ASMTL-AS1 on LUAD. Moreover, mechanism assays were done to confirm the relationship among ASMTL-AS1, SAT1 and U2AF2. Results showed that ASMTL-AS1 was down-regulated in LUAD cells and ASMTL-AS1 up-regulation resulted in retarded LUAD cell and xenograft tumor growth along with stimulated ferroptosis. ASMTL-AS1 recruited U2AF2 to stabilize SAT1 mRNA. Furthermore, SAT1 exerted a cancer suppressor role in LUAD cells. In conclusion, we first demonstrated that ASMTL-AS1 positively regulated SAT1 to promote ferroptosis and could stabilize SAT1 mRNA via recruiting U2AF2, shedding a light on a novel molecular mechanism in LUAD progression.

Ferroptosis and Cancer: Complex Relationship and Potential Application of Exosomes

Cell death induction has become popular as a novel cancer treatment. Ferroptosis, a newly discovered form of cell death, features regulated, iron-dependent accumulation of lipid hydroperoxides. Since this word “ferroptosis” was coined, numerous studies have examined the complex relationship between ferroptosis and cancer. Here, starting from the intrinsic hallmarks of cancer and cell death, we discuss the theoretical basis of cell death induction as a cancer treatment. We review various aspects of the relationship between ferroptosis and cancer, including the genetic basis, epigenetic modification, cancer stem cells, and the tumor microenvironment, to provide information and support for further research on ferroptosis. We also note that exosomes can be applied in ferroptosis-based therapy. These extracellular vesicles can deliver different molecules to modulate cancer cells and cell death pathways. Using exosomes to control ferroptosis occurring in targeted cells is promising for cancer therapy.

Identification of Ferroptosis-Related Long Noncoding RNA and Construction of a Novel Prognostic Signature for Gastric Cancer

Background

Gastric cancer is the most common malignant tumor of the digestive system. It has a poor prognosis and is clinically challenging to treat. Ferroptosis is a newly defined mode of programmed cell death. The roles and prognostic value of ferroptosis-related long noncoding RNAs (lncRNAs) in gastric cancer remain unknown.

Results

In the current study, 20 ferroptosis-related lncRNAs were identified via univariate Cox analysis, least absolute shrinkage, and selection operator Cox regression analysis and used to construct a prognostic signature and classify gastric cancer patients into high-risk and low-risk groups. The signature was validated using TCGA training and testing cohorts. The risk signature was an independent prognostic indicator of survival and accurately predicted the prognoses of patients with gastric cancer. It was also associated with immune cell infiltration. Gene set enrichment analysis was used to investigate underlying mechanisms that the 20 ferroptosis-related lncRNAs were involved in. Chemosensitivity and immune checkpoint inhibitor analyses indicated that high-risk patients were more sensitive to the immune checkpoint inhibitor programmed cell death protein 1.

Conclusions

The important role of ferroptosis-related lncRNAs in immune infiltration identified in the current study may assist the determination of personalized prognoses and treatments in patients with gastric cancer. These 20 lncRNAs can be used as the diagnostic and prognostic markers for gastric cancer.

A Promising Future of Ferroptosis in Tumor Therapy

Currently, mechanisms and therapeutic approaches have been thoroughly studied in various prevalent malignant tumors, such as breast and lung cancer. However, there is inevitable tumor progression and drug resistance. Uncovering novel treatment strategies to inhibit tumor development is important. Ferroptosis, a form of cell death associated with iron and lipid peroxidation, has drawn extensive attention. In this paper, we reviewed the underlying mechanisms of ferroptosis (i.e., iron, glutathione, and lipid metabolism) and its role in various tumors (i.e., lung cancer, liver carcinoma, breast cancer, and pancreatic cancer). Moreover, we summarized ferroptosis-related anti-tumor drugs and emphasized the potential of combined treatment of anti-tumor drugs and radiotherapy in an effort to provide novel anti-tumor treatments.