Novel insights into the SLC7A11-mediated ferroptosis signaling pathways in preeclampsia patients: identifying pannexin 1 and toll-like receptor 4 as innovative prospective diagnostic biomarkers

Heme oxygenase/carbon monoxide system affects the placenta and preeclampsia

Preeclampsia affects 2% to 8% of pregnancies worldwide and results in significantly high maternal and perinatal morbidity and mortality, with delivery being the only definitive treatment. It is not a single disorder, but rather a manifestation of an insult(s) to the uteroplacental unit -whether maternal, fetal, and/or placental. Multiple etiologies have been implicated, including uteroplacental ischemia, maternal infection and/or inflammation, maternal obesity, sleep disorders, hydatidiform mole, maternal intestinal dysbiosis, autoimmune disorders, fetal diseases, breakdown of maternal-fetal immune tolerance, placental aging, and endocrine disorders. Early- and late-onset preeclampsia are associated with different etiologies: early-onset preeclampsia develops because of poor placentation, while late-onset preeclampsia occurs in women with latent maternal endothelial dysfunction. In preeclamptic placentas, acquired, genetic, and immune risk factors may result in impaired trophoblast invasion and spiral artery remodeling, which affects uteroplacental perfusion. The resulting placental hypoxia affects the heme oxygenase system-a known stress response pathway affected by hypoxia that is important during normal pregnancy and may offer a therapeutic approach in preeclampsia. This review will address the effect of the heme oxygenase/carbon monoxide system on the placenta and preeclampsia.

Exploration of ferroptosis-related biomarkers with prognostic capability in RIF based on WGCNA

PURPOSE

To explore the association of ferroptosis with repeated implantation failure (RIF) and prognostic capability of ferroptosis-related genes.

METHODS

Data in GSE106602 from the GEO database were used for gene co-expression network construction to confirm ferroptosis-related genes compared to gene sets that were downloaded from FerrDB. Then these genes were analyzed for functional enrichment and validated using endometrium samples from our center. ImplantScore and ROC curve were constructed for prognostic correlation analysis.

RESULTS

We observed that ferroptosis probably participated in RIF according to bioinformatics analysis on a gene set which exhibited a strong association with RIF from WGCNA. Fifty-four ferroptosis-related genes in the gene set were subsequently verified, and the PPI network was established for underlying interactions among them. There were 23 hub genes with differential expression in RIF and six of them (PML, LCN2, PRKAA1, BACH1, SLC7A11, and CAMKK2) showed significant correlation with implantation outcomes using samples collected from our center. Therefore, we combined the six genes and constructed an ImplantScore whose AUC reached 0.891, higher than the AUC of each single gene, respectively. ImplantScore of six genes with down-regulated expression in the group with failed implantation were much lower than that with successful outcome.

CONCLUSION

Our results demonstrated the potential prognostic functions of ferroptosis-related biomarkers in RIF, which will provide novel perspectives for further research and clinical applications.

miR-224-5p alleviates preeclampsia-like mouse symptoms by targeting PANX1 to inhibit ferroptosis in trophoblast cells

Preeclampsia (PE) is a high morbidity and lethality disease specific to pregnancy, and insufficient placental trophoblast invasion acts as a crucial factor contributing to PE development. The present study investigated the function and potential mechanism of microRNA (miR)-224-5p within PE. In the study, miR-224-5p expression was reduced within placental tissue samples of the PE mouse model and PE cell model. Restoration of miR-224-5p expression markedly inhibited ROS levels and ferroptosis, lowered blood pressure in pregnant mice, increased the live birth rate, and enhanced trophoblast cell proliferation and invasion as well as suppressed their apoptosis. miR-224-5p could target and suppress PANX1, and overexpression of PANX1 could significantly advance ferroptosis and cause trophoblast dysfunction, a process that might be relieved via restoring miR-224-5p expression. In conclusion, miR-224-5p/PANX1 ameliorates trophoblast dysfunction by inhibiting ferroptosis, which provides a potential new option for clinical treatment of PE.

Understanding the intersection between placental development and cancer: Lessons from the tumor suppressor BAP1

The placenta, a pivotal organ in mammalian reproduction, allows nutrient exchange and hormonal signaling between the mother and the developing fetus. Understanding its molecular intricacies is essential for deciphering normal embryonic development and pathological conditions such as tumorigenesis. Here, we explore the multifaceted role of the tumor suppressor BRCA1-associated protein 1 (BAP1) in cancer and placentation. Initially recognized for its tumor-suppressive properties, BAP1 has emerged as a key regulator at the intersection of tumorigenesis and placental development. BAP1 influences crucial cellular processes such as cell death, proliferation, metabolism, and response to hypoxic conditions. By integrating insights from tumor and developmental biology, we illuminate the complex molecular pathways orchestrated by BAP1. This perspective highlights BAP1's significant impact on both cancer and placental development, and suggests novel therapeutic strategies that could improve outcomes for pregnancy disorders and cancer.

Epigallocatechin gallate (EGCG) alleviates inflammation and endothelial dysfunction and improves pregnancy outcomes in preeclampsia (PE)-like rats via eNOS/Nrf2/HO-1 pathway

BACKGROUND AND PURPOSE

Epigallocatechin gallate (EGCG), a natural antioxidant, has shown protective effect in many diseases. We explore the effect and potential regulatory mechanisms of EGCG in preeclampsia (PE)-like rats.

METHODS AND MATERIALS

PE was mimicked in pregnant rats. EGCG was orally administered at a dosage of 25(Low, L) or 50 mg/kg (High, H) from gestational day (GD) 6-17. The blood pressure signatures, heart rates were monitored. The 24-h proteinuria and serum were analyzed. On GD 18, rats were sacrificed, and pups and placentas were weighed. Kidneys and placentas were analyzed using immunohistochemistry (IHC) and hematoxylin-eosin staining (H&E). Placentas were examined using western blot for sFlt1, eNOS, Nrf2, HO-1, SLC7A11. MDA, GSH, GPx and Fe2+ were measured.

RESULTS

EGCG inhibits systolic blood pressure, BUN, CREA, ALT, AST, UA and proteinuria levels in PE-like rats. EGCG enhances the pup weight and crown-rump length and reduces the rate of fetus growth restriction in PE group. Endothelial dysfunction and infiltration of inflammatory cells were found in kidney cortex and placenta tissues in PE group and were inhibited by EGCG treatment. sFlt1 was activated in placentas in PE group and inhibited by EGCG while eNOS/Nrf2/HO-1 were inhibited in PE group and restored by EGCG. MDA and Fe concentrations were elevated in PE group and reduced by EGCG while the GSH level, SLC7A11 and the GPx activity were inhibited in PE group and restored by EGCG.

CONCLUSION

EGCG alleviates inflammation, endothelial dysfunction and placental ferroptosis, improves pregnancy outcomes in PE-like rats via eNOS/Nrf2/HO-1.

Unraveling the role of sulfiredoxin-1 in early-onset preeclampsia: A key player in trophoblast ferroptosis

Preeclampsia (PE) significantly contributes to obstetric complications and maternal mortality, yet its pathogenesis and mechanisms are not well understood. Sulfiredoxin-1 (SRXN1) is known for its antioxidant activity and its role in defending against oxidative stress; it is also linked to various cancers. However, the role of SRXN1 in PE remains unclear. Our study found a significant decrease in SRXN1 levels in the serum and placental tissues of patients with early-onset preeclampsia (EOPE). Similarly, a PE-like mouse model showed reduced SRXN1 expression. Our in vitro experiments showed that reducing SRXN1 impaired trophoblast viability, decreased invasion and migration, and led to cell death, primarily through ferroptosis. These results are consistent with analyses of placental tissues from EOPE patients. In summary, lower SRXN1 levels during pregnancy contribute to trophoblast ferroptosis, potentially affecting the development and progression of EOPE.

The crosstalk between cell death and pregnancy related diseases: A narrative review

Programmed cell death is intricately linked to various physiological phenomena such as growth, development, and metabolism, as well as the proper function of the pancreatic β cell and the migration and invasion of trophoblast cells in the placenta during pregnancy. Traditional and recently identified programmed cell death include apoptosis, autophagy, pyroptosis, necroptosis, and ferroptosis. In addition to cancer and degenerative diseases, abnormal activation of cell death has also been implicated in pregnancy related diseases like preeclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, fetal growth restriction, and recurrent miscarriage. Excessive or insufficient cell death and pregnancy related diseases may be mutually determined, ultimately resulting in adverse pregnancy outcomes. In this review, we systematically describe the characteristics and mechanisms underlying several types of cell death and their roles in pregnancy related diseases. Moreover, we discuss potential therapeutic strategies that target cell death signaling pathways for pregnancy related diseases, hoping that more meaningful treatments will be applied in clinical practice in the future.

Nicorandil Regulates Ferroptosis and Mitigates Septic Cardiomyopathy via TLR4/SLC7A11 Signaling Pathway

This study mainly explored the role of nicorandil in regulating ferroptosis and alleviating septic cardiomyopathy through toll-like receptor (TLR) 4/solute carrier family 7 member 11 (SLC7A11) signaling pathway. Twenty-four male SD rats were randomly divided into control, Nic (nicorandil), LPS (lipopolysaccharide), and LPS + Nic groups and given echocardiography. A detection kit was applied to measure the levels of lactic dehydrogenase (LDH), cardiac troponin I (cTnI), and creatine kinase-MB (CK-MB); HE staining and the levels of glutathione (GSH), malondialdehyde (MDA), total iron, and Fe2+ of myocardial tissues were detected. Moreover, the expression of TLR4 and SLC7A11 were measured by qRT-PCR and the proteins regulating ferroptosis (TLR4, SLC7A11, GPX4, ACSL4, DMT1, Fpn, and TfR1) were checked by western blot. Myocardial cells (H9C2) were induced with lipopolysaccharide (LPS) and transfected with si-TLR4 or SLC7A11-OE. Then, the viability, ferroptosis, and TLR4/SLC7A11 signaling pathway of cells were examined. Nicorandil could significantly increase left ventricular (LV) ejection fraction (LVEF) while reduce LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV). Also, it greatly reduced the levels of LDH, cTnI, and CK-MB; alleviated the pathological changes of myocardial injury; notably decreased MDA, total iron, and Fe2+ levels in myocardial tissues; and significantly increased GSH level. Besides, nicorandil obviously raised protein levels of GPX4, Fpn, and SLC7A11, and decreased protein levels of ACSL4, DMT1, TfR1, and TLR4. After knockdown of TLR4 or overexpression of SLC7A11, the inhibition effect of nicorandil on ferroptosis was strengthened in LPS-induced H9C2 cells. Therefore, nicorandil may regulate ferroptosis through TLR4/SLC7A11 signaling, thereby alleviating septic cardiomyopathy.

Physical and social environmental enrichment alleviate ferroptosis and inflammation with inhibition of TLR4/MyD88/p38MAPK pathway in chronic cerebral hypoperfusion rats

A typical enriched environment (EE), which combines physical activity and social interaction, has been proven to mitigate cognitive impairment caused by chronic cerebral hypoperfusion (CCH). However, it remains unclear how the different components of EE promote cognitive recovery after CCH. This study stripped out the different components of EE into physical environmental enrichment (PE) and social environmental enrichment (SE), and compared the neuroprotective effects of PE, SE and typical EE (PSE) in CCH. The results of novel object recognition and Morris water maze tests showed that PE, SE, and PSE improved cognitive function in CCH rats. Additionally, Nissl and TUNEL staining revealed that three EEs reduced neuronal loss in the hippocampus. PSE exhibited superior neuroprotective and functional improvement effects compared to PE and SE, while there was no significant difference between PE and SE. Furthermore, three EEs reduced lipid peroxidation in the hippocampus with decreasing the levels of MDA and increasing the activities of SOD and GSH. The expression of SLC7A11 and GPX4 was increased, while the level of p53 was reduced in three EEs. This suggested that three EEs inhibited ferroptosis by maintaining the redox homeostasis in the hippocampus. Three EEs reduced the levels of IL-β, TNF-α, and IL-6, thereby inhibiting neuroinflammation. Additionally, Western blotting and immunofluorescence results indicated that three EEs also inhibited the TLR4/MyD88/p38MAPK signaling pathway. These findings collectively demonstrated that the three EEs alleviated hippocampal ferroptosis and neuroinflammation in CCH rats, thereby reducing neuronal loss, which might be associated with the inhibition of the TLR4/MyD88/p38MAPK signaling pathway. Moreover, the study results supported that it is only through the combination of physical exercise and social interaction that the optimal neuroprotective effects can be achieved. These findings provided valuable insights for the prevention and treatment of vascular cognitive impairment.

Impact of ferroptosis on preeclampsia: A review

Preeclampsia (PE) is usually associated with the accumulation of reactive oxygen species (ROS) resulting from heightened oxidative stress (OS). Ferroptosis is a unique type of lipid peroxidation-induced iron-dependent cell death distinct from traditional apoptosis, necroptosis, and pyroptosis and most likely contributes considerable to PE pathogenesis. At approximately 10-12 weeks of gestation, trophoblasts create an environment rich in oxygen and iron. In patients with PE, ferroptosis-related genes such as HIF1 and MAPK8 are downregulated, whereas PLIN2 is upregulated. Furthermore, miR-30b-5p overexpression inhibits solute carrier family 11 member 2, resulting in a decrease in glutathione levels and an increase in the labile iron pool. At the maternal-fetal interface, physiological hypoxia/reperfusion and excessive iron result in lipid peroxidation and ROS production. Owing to the high expression of Fpn and polyunsaturated fatty acid-containing phospholipid-related enzymes, including acyl-CoA synthetase long-chain family member 4, lysophosphatidylcholine acyl-transferase 3, and spermidine/spermine N1-acetyltransferase 1, trophoblasts become more susceptible to OS and ROS damage. In stage 1, the injured trophoblasts exhibit poor invasion and incomplete uterine spiral artery remodeling caused by ferroptosis, leading to placental ischemia and hypoxia. Subsequently, ferroptosis marked by OS occurs in stage 2, eventually causing PE. We aimed to explore the new therapeutic target of PE through OS in ferroptosis.

Iron metabolism and ferroptosis: A pathway for understanding preeclampsia

Preeclampsia (PE) is a serious medical condition that poses a significant health risk to women and children worldwide, particularly in the middle- and low-income countries. It is a complex syndrome that occurs as a result of abnormal pregnancy. Hypertension is the most common symptom of PE, with proteinuria and specific organ systems as detrimental targets. PE's pathogenesis is diverse, and its symptoms can overlap with other diseases. In early pregnancy, when the placenta takes over control, oxidative stress may be closely associated with ferroptosis, a type of cell death caused by intracellular iron accumulation. Ferroptosis in the placenta is defined by redox-active iron availability, loss of antioxidant capacity and phospholipids containing polyunsaturated fatty acids (PUFA) oxidation. Recent studies suggest a compelling potential link between ferroptosis and PE. In this article, we comprehensively review the current understanding of PE and discuss one of its emerging underlying mechanisms, the ferroptosis pathway. We also provide perspective and analysis on the implications of this process in the diagnosis, prevention, and treatment of preeclampsia. We aim to bridge the gap between clinicians and basic scientists in understanding this harmful disease and challenge the research community to put more effort into this exciting new area.

Characterization of the lncRNA-mediated ceRNA regulatory networks in preeclampsia by integrated bioinformatics

Preeclampsia (PE) is a significant threat to all pregnancies that is highly associated with maternal mortality and developmental disorders in infants. However, the etiopathogenesis of this condition remains unclear. This study aims to explore the regulatory roles of long noncoding RNAs (lncRNAs) and the mediated competing endogenous RNAs (ceRNA) in the etiopathogenesis of PE through analysis of lncRNA expression patterns in PE and healthy pregnant women (HPW), as well as the construction of lncRNA-mediated ceRNA regulatory networks using bioinformatics. A total of 896 significant differentially expressed lncRNAs, including 586 upregulated lncRNAs and 310 downregulated lncRNAs, were identified in comparison between PE and HPW. Analysis of these differential expressed lncRNAs revealed their predominant enrichment in molecular functions such as sphingosine-1-phosphate phosphatase activity, lipid phosphatase activity, phosphatidate phosphatase activity, thymidylate kinase activity, and UMP kinase activity. Moreover, these differential expressed lncRNAs were predominantly enriched in KEGG analyses such as fat digestion and absorption, lysine degradation, ether lipid metabolism, glycerolipid metabolism, and sphingolipid metabolism. Two ceRNA regulatory networks were constructed based on ceRNA score, including one that had 31 upregulated lncRNAs, 11 downregulated miRNAs, and 34 upregulated mRNAs, while the other contained 128 downregulated lncRNAs, 40 upregulated miRNAs, and 113 downregulated mRNAs. These results may provide a clue to explore the roles of lncRNAs in the etiopathogenesis of PE.

Pannexin1 channels in the liver: an open enemy

Pannexin1 proteins form communication channels at the cell plasma membrane surface, which allow the transfer of small molecules and ions between the intracellular compartment and extracellular environment. In this way, pannexin1 channels play an important role in various cellular processes and diseases. Indeed, a plethora of human pathologies is associated with the activation of pannexin1 channels. The present paper reviews and summarizes the structure, life cycle, regulation and (patho)physiological roles of pannexin1 channels, with a particular focus on the relevance of pannexin1 channels in liver diseases.

Reversal of H2O2-induced cell death by knockdown of HOTAIR in HTR-8/SVneo cells by mediation of miR-106b-5p/ACSL4 axis

Preeclampsia is a serious threat to the health of pregnant women. Injury of trophoblasts could contribute to the progression of preeclampsia, and H₂O₂ was able to induce apoptosis in trophoblasts. LncRNAs have been reported to be involved in the progression of preeclampsia. Additionally, lncRNA HOTAIR is upregulated in patients with preeclampsia. However, the function of HOTAIR in H₂O₂-treated trophoblasts remains unclear. To explore the function of HOTAIR in preeclampsia, HTR-8/SVneo cells were stimulated with H₂O₂. RT-qPCR was performed to measure HOTAIR expression in HTR-8/SVneo cells. The apoptosis of HTR-8/SVneo cells was measured using TUNEL staining. The mitochondrial membrane potential was measured using JC-1 staining. Western blotting was performed to detect the expression of ACSL4, GPX4, and FTH1 in HTR-8/SVneo cells. The level of HOTAIR in HTR-8/SVneo cells was upregulated by H₂O₂. In addition, H₂O₂ notably inhibited the proliferation of HTR-8/SVneo cells, whereas knockdown of HOTAIR reversed this phenomenon. The mitochondrial membrane potential in HTR-8/SVneo cells was significantly inhibited by H₂O₂ and partially abolished by HOTAIR silencing. Moreover, HOTAIR could bind to miR-106b-5p; ACSL4 was identified as the downstream target of miR-106b-5p. Furthermore, HOTAIR knockdown reversed H₂O₂-induced ferroptosis in HTR-8/SVneo cells by regulating miR-106b-5p/ACSL4. Collectively, the knockdown of HOTAIR reversed H₂O₂-induced ferroptosis in HTR-8/SVneo cells by mediating miR-106b-5p/ACSL4. Thus, HOTAIR may serve as a new therapeutic target against preeclampsia.

Procyanidins Alleviated Cerebral Ischemia/Reperfusion Injury by Inhibiting Ferroptosis via the Nrf2/HO-1 Signaling Pathway

Procyanidins (PCs), which are organic antioxidants, suppress oxidative stress, exhibit anti-apoptotic properties, and chelate metal ions. The potential defense mechanism of PCs against cerebral ischemia/reperfusion injury (CIRI) was investigated in this study. Pre-administration for 7 days of a PC enhanced nerve function and decreased cerebellar infarct volume in a mouse middle cerebral artery embolization paradigm. In addition, mitochondrial ferroptosis was enhanced, exhibited by mitochondrial shrinkage and roundness, increased membrane density, and reduced or absent ridges. The level of Fe²⁺ and lipid peroxidation that cause ferroptosis was significantly reduced by PC administration. According to the Western blot findings, PCs altered the expression of proteins associated with ferroptosis, promoting the expression of GPX4 and SLC7A11 while reducing the expression of TFR1, hence inhibiting ferroptosis. Moreover, the treatment of PCs markedly elevated the expression of HO-1 and Nuclear-Nrf2. The PCs' ability to prevent ferroptosis due to CIRI was decreased by the Nrf2 inhibitor ML385. Our findings showed that the protective effect of PCs may be achieved via activation of the Nrf2/HO-1 pathway and inhibiting ferroptosis. This study provides a new perspective on the treatment of CIRI with PCs.

Role of ferroptosis in pregnancy related diseases and its therapeutic potential

Ferroptosis is a form of regulated cell death characterized by iron overload, overwhelming lipid peroxidation, and disruption of antioxidant systems. Emerging evidence suggests that ferroptosis is associated with pregnancy related diseases, such as spontaneous abortion, pre-eclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, and spontaneous preterm birth. According to these findings, inhibiting ferroptosis might be a potential option to treat pregnancy related diseases. This review summarizes the mechanisms and advances of ferroptosis, the pathogenic role of ferroptosis in pregnancy related diseases and the potential medicines for its treatment.

Establishment of Ferroptosis-Related Key Gene Signature and Its Validation in Compression-Induced Intervertebral Disc Degeneration Rats

Cell death and functional loss of nucleus pulposus cell play essential roles in intervertebral disc degeneration (IDD). Ferroptosis is a newly identified cell death type, and its role in IDD is still under investigation. Identifying the key genes of ferroptosis in IDD helps to identify the therapeutic targets of IDD. In this study, we downloaded the human IDD mRNA microarray data from the Gene Expression Omnibus and ferroptosis genes from FerrDb, then performed a series of analyses using strict bioinformatics algorithms. In general, we obtained 40 ferroptosis-related differential expression genes (FerrDEGs) and identified six ferroptosis key gene signatures, namely, ATF3, EIF2S1, AR, NQO1, TXNIP, and AKR1C3. In addition, enrichment analysis of the FerrDEGs was conducted, the protein-protein interaction network was constructed, the correlations between ferroptosis key genes and immune infiltrating cells were analyzed, and the lncRNA-miRNA-mRNA ceRNA network was constructed. In particular, ATF3 and EIF2S1 showed the strongest correlation with immune cell function, which might lead to the development of IDD. Finally, the expressions of ferroptosis key genes were verified in the rat compression-induced IDD. In conclusion, this preliminary study analyzed and verified the mechanism of ferroptosis in IDD, laid a foundation for the follow-up study of the mechanism of ferroptosis in IDD, and provided new targets for preventing and delaying IDD.

Placental ion channels: potential target of chemical exposure

The placenta is an important organ for the exchange of substances between the fetus and the mother, hormone secretion, and fetoplacental immunological defense. Placenta has an organ-specific distribution of ion channels and trophoblasts, and placental vessels express a large number of ion channels. Several placental housekeeping activities and pregnancy complications are at least partly controlled by ion channels, which are playing an important role in regulating hormone secretion, trophoblastic homeostasis, ion transport, and vasomotor activity. The function of several placental ion channels (Na, Ca, and Cl ion channels, cation channel, nicotinic acetylcholine receptors, and aquaporin-1) is known to be influenced by chemical exposure, i.e., their responses to different chemicals have been tested and confirmed in experimental models. Here, we review the possibility that placental ion channels are targets of toxicological concern in terms of placental function, fetal growth, and development.

Ferroptosis-Related Proteins Are Potential Diagnostic Molecular Markers for Patients with Preeclampsia

Preeclampsia (PE) is the leading cause of maternal and fetal mortality and morbidity. Early and accurate diagnosis is critical to reduce mortality. Placental oxidative stress has been identified as a major pathway to the development of PE. Ferroptosis, a new form of regulated cell death, is associated with iron metabolism and oxidative stress, and has been suspected to play a role in the pathophysiology of PE, although the mechanism is yet to be elucidated. The identification of potential ferroptosis-related biomarkers is of great significance for the early diagnosis and treatment of PE. A gene expression dataset of peripheral blood samples was downloaded from the Gene Expression Omnibus (GEO) dataset. Differentially expressed genes (DEGs) were filtrated with the R package “limma”. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of the DEGs were then conducted. Ferroptosis-related DEGs were screened by overlapping the ferroptosis-related genes with DEGs. The protein−protein interaction (PPI) network was used to identify the key ferroptosis-related DEGs. Enzyme-linked immunosorbent assay (ELISA) was used to validate changes in the selected key ferroptosis-related DEGs. The correlations between the key genes and clinical and pathological characteristics were analyzed. Finally, the diagnostic value of these key genes for PE was confirmed by a receiver operating characteristic (ROC) curve. A total of 5913 DEGs were identified and 45 ferroptosis-related DEGs were obtained. Besides, ferroptosis-related pathways were enriched by KEGG using DEGs. The PPI network showed that p53 and c-Jun were the critical hub genes. ELISA showed that p53 in the serum of PE patients was higher than that of the control group, while c-Jun was lower than that of the control group. Analysis of the clinicopathological features showed that p53 and c-Jun were correlated with the PE characteristics. Finally, based on the area under curve (AUC) values, c-Jun had the superior diagnostic power (AUC = 0.87, p < 0.001), followed by p53 (AUC = 0.75, p < 0.001). Our study identified that two key genes, p53 and c-Jun, might be potential diagnostic biomarkers of PE.

Development and Validation of a Novel Ferroptosis-Related LncRNA Signature for Predicting Prognosis and the Immune Landscape Features in Uveal Melanoma

Background

Ferroptosis is a newly iron-dependent mode of programmed cell death that is involved in a variety of malignancies. But no research has shown a link between ferroptosis-related long non-coding RNAs (FRLs) and uveal melanoma (UM). We aimed to develop a predictive model for UM and explore its potential function in relation to immune cell infiltration.

Methods

Identification of FRLs was performed using the Cancer Genome Atlas (TCGA) and FerrDb databases. To develop a prognostic FRLs signature, univariate Cox regression and least absolute shrinkage and selection operator (LASSO) were used in training cohort. Kaplan-Meier (K-M) and receiver operating characteristic (ROC) curve analyses were used to assess the reliability of the risk model. The immunological functions of FRLs signature were determined using gene set enrichment analysis (GSEA). Immunological cell infiltration and immune treatment were studied using the ESTIMATE, CIBERSORT, and ssGSEA algorithms. Finally, in vitro assays were carried out to confirm the biological roles of FRLs with known primer sequences (LINC00963, PPP1R14B.AS1, and ZNF667.AS1).

Results

A five-genes novel FRLs signature was identified. The mean risk score generated by this signature was used to create two risk groups. The high-risk score UM patients had a lower overall survival rate. The area under the curve (AUC) of ROC and K-M analysis further validated the strong prediction capacity of the prognostic signature. Immune cells such as memory CD8 T cells, M1 macrophages, monocytes, and B cells showed a substantial difference between the two groups. GSEA enrichment results showed that the FRLs signature was linked to certain immune pathways. Moreover, UM patients with high-risk scores were highly susceptible to several chemotherapy drugs, such as cisplatin, imatinib, bortezomib, and pazopanib. Finally, the experimental validation confirmed that knockdown of three identified lncRNA (LINC00963, PPP1R14B.AS1, and ZNF667.AS1) suppressed the invasive ability of tumor cells in vitro.

Conclusion

The five-FRLs (AC104129.1, AC136475.3, LINC00963, PPP1R14B.AS1, and ZNF667.AS1) signature has effects on clinical survival prediction and selection of immunotherapies for UM patients.