Ferroptosis: Redox Imbalance and Hematological Tumorigenesis

Fe3O4-Coated CNTs-Gum Arabic Nano-Hybrid Composites Exhibit Enhanced Anti-Leukemia Potency Against AML Cells via ROS-Mediated Signaling

Background

Prior studies on magnetite (Fe3O4) NPs and carbon nanotubes (CNTs) cytotoxic effects against acute myeloid leukemia (AML) are inconclusive rather than definitive.

Purpose

Investigation of the effects of Gum Arabic (GA)-stabilized/destabilized Fe3O4 NPs and CNTs, alone or in combination, on AML cell proliferation.

Methods

Hybrid NPs were synthesized, characterized, and assessed for their cytotoxicity against Kasumi-1, HL-60, and THP-1 in comparison to normal primary bone marrow CD34+ cells. The molecular pathways of nanostructures' cytotoxicity were also investigated.

Results

The Fe3O4 NPs were effectively synthesized and attached to the surface of the CNTs, resulting in the formation of a novel hybrid through their interaction with the GA colloidal solution in an aqueous media. Although the evaluated nanostructured nanoparticles had significant growth suppression ability against the leukemia cell lines, with IC50 values ranging from 42.437 to 189.842 μg/mL, they exhibited comparatively modest toxicity towards normal hematopoietic cells (IC50: 113.529‒162.656 μg/mL). The incorporation of Fe3O4 NPs with CNTs in a hybrid nanocomposite significantly improved their effectiveness against leukemia cells, with the extent of improvement varying depending on the specific cell type. The nanostructured particles were stabilized by GA, which enhances their ability to inhibit cell proliferation in a manner that depends on the specific cell type. Also, nanoparticles exhibit cytotoxicity due to their capacity to stimulate the production of intracellular ROS, halt the cell cycle at the G1 phase, and induce apoptosis. This is supported by the activation of p53, BAX, cytochrome C, and caspase-3, which are triggered by ROS. The nanostructures lead to an increase in the expression of genes encoding proteins related to oxidative stress (SIRT1, FOXO3, NFE2L2, and MAP3K5) and cyclin-dependent kinase inhibitors (CDKN1A and CDKN1B) in response to ROS.

Conclusion

We provide an effective Fe3O4 NPs/CNTs nano-hybrid composite that induces apoptosis and has strong anti-leukemic capabilities. This hybrid nanocomposite is promising for in vivo testing and validation.

Surufatinib combined with photodynamic therapy induces ferroptosis to inhibit cholangiocarcinoma in vitro and in tumor models

The curative effect of single therapy for advanced cholangiocarcinoma (CCA) is poor, thus investigating combined treatment strategies holds promise for improving prognosis. Surufatinib (SUR) is a novel multikinase inhibitor that has been confirmed to prolong survival of patients with advanced CCA. Photodynamic therapy (PDT) can also ablate advanced CCA and relieve biliary obstruction. In this study, we explored the anti-CCA effect of SUR combined with PDT, and explored the underlying mechanism. We found that SUR could effectively inhibit the abilities of proliferation, migration and metastasis in CCA cells (HUCCT-1, RBE). The ability of SUR to inhibit CCA was also confirmed by the HUCCT-1 cell xenograft model in Balb/c nude mice and CCA patient-derived organoids. SUR combined with PDT can significantly enhance the inhibitory effect on CCA, and can be alleviated by two ferroptosis inhibitors (Ferrostatin-1, Deferoxamine). By detecting the level of reactive oxygen species, lipid peroxides, malondialdehyde and glutathione, we further confirmed that SUR combined with PDT can inhibit CCA cells by inducing ferroptosis. Glutathione peroxidase 4 (GPX4) belongs to the glutathione peroxidase family and is mainly responsible for the metabolism of intracellular hydrogen peroxide. GPX4 inhibits ferroptosis by reducing cytotoxic lipid peroxides (L-OOH) to the corresponding alcohols (L-OH). Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a member of the long-chain fatty acid coenzyme a synthetase family and is mainly involved in the biosynthesis and catabolism of fatty acids. ACSL4 induces ferroptosis by promoting the accumulation of lipid peroxides. Both SUR and PDT can induce ferroptosis by promoting ACSL4 and inhibiting GPX4. The regulation effect is found to be more significant in combined treatment group. In conclusion, SUR combined with PDT exerted an anti-CCA effect by inducing ferroptosis. Combination therapy provides a new idea for the clinical treatment of CCA.

Cellular metabolism: A key player in cancer ferroptosis

Cellular metabolism is the fundamental process by which cells maintain growth and self-renewal. It produces energy, furnishes raw materials, and intermediates for biomolecule synthesis, and modulates enzyme activity to sustain normal cellular functions. Cellular metabolism is the foundation of cellular life processes and plays a regulatory role in various biological functions, including programmed cell death. Ferroptosis is a recently discovered form of iron-dependent programmed cell death. The inhibition of ferroptosis plays a crucial role in tumorigenesis and tumor progression. However, the role of cellular metabolism, particularly glucose and amino acid metabolism, in cancer ferroptosis is not well understood. Here, we reviewed glucose, lipid, amino acid, iron and selenium metabolism involvement in cancer cell ferroptosis to elucidate the impact of different metabolic pathways on this process. Additionally, we provided a detailed overview of agents used to induce cancer ferroptosis. We explained that the metabolism of tumor cells plays a crucial role in maintaining intracellular redox homeostasis and that disrupting the normal metabolic processes in these cells renders them more susceptible to iron-induced cell death, resulting in enhanced tumor cell killing. The combination of ferroptosis inducers and cellular metabolism inhibitors may be a novel approach to future cancer therapy and an important strategy to advance the development of treatments.

Targeting ferroptosis and ferritinophagy: new targets for cardiovascular diseases

Cardiovascular diseases (CVDs) are a leading factor driving mortality worldwide. Iron, an essential trace mineral, is important in numerous biological processes, and its role in CVDs has raised broad discussion for decades. Iron-mediated cell death, namely ferroptosis, has attracted much attention due to its critical role in cardiomyocyte damage and CVDs. Furthermore, ferritinophagy is the upstream mechanism that induces ferroptosis, and is closely related to CVDs. This review aims to delineate the processes and mechanisms of ferroptosis and ferritinophagy, and the regulatory pathways and molecular targets involved in ferritinophagy, and to determine their roles in CVDs. Furthermore, we discuss the possibility of targeting ferritinophagy-induced ferroptosis modulators for treating CVDs. Collectively, this review offers some new insights into the pathology of CVDs and identifies possible therapeutic targets.

Potential applications of ferroptosis inducers and regulatory molecules in hematological malignancy therapy

Ferroptosis, a novel form of iron-dependent cell death, has emerged as a potential avenue for promoting tumor cell death by causing cell membrane rupture and the accumulation of lipid peroxides (LPO) in the cell. Since its discovery in 2012, extensive research has been conducted to explore the mechanism of ferroptosis inducers, including erastin, sulfasalazine, and sorafenib. These compounds inhibit system XC-, while Ras-selective lethal small molecule 3 (RSL3) and FION2 specifically target GPX4 to promote ferroptosis. Therefore, targeting ferroptosis presents a promising therapeutic approach for malignant tumors. While the study of ferroptosis in solid tumors has made significant progress, there is limited information available on its role in hematological tumors. This review aims to summarize the molecular mechanisms of ferroptosis inducers and discuss their clinical applications in hematological malignancies. Furthermore, the identification of non-coding RNAs (ncRNAs) and genes that regulate key molecules in the ferroptosis pathway could provide new targets and establish a molecular theoretical foundation for exploring novel ferroptosis inducers in hematological malignancies.

Silencing LCN2 enhances RSL3-induced ferroptosis in T cell acute lymphoblastic leukemia

BACKGROUND

T-cell acute lymphoblastic leukemia (T-ALL) is a life-threatening malignancy and therapeutic toxicity remains a huge challenge for survival rates. A novel iron-dependent form of cell death, ferroptosis, shows potentials in cancer therapy. This study aimed to identify ferroptosis-associated hub genes within a proteinprotein interaction (PPI) network.

METHODS

We screened differential expressed genes (DEGs) in GSE46170 dataset and obtained ferroptosis-related genes from FerrDb database. Through overlapping between DEGs and ferroptosis-related genes, ferroptosis-associated DEGs were identified for further PPI network construction. Molecular complex detection (MCODE) algorithm in Cytoscape was employed to determine tightly connected protein clusters. Chord diagram of Gene Ontology (GO) was generated to reveal the potential biological process of hub genes. Through transfection with siRNA of lipocalin 2 (LCN2) into TALL cells, the regulatory role of LCN2 in ferroptosis was investigated.

RESULTS

Venn diagram identified a total of 37 ferroptosis-associated DEGs between GSE46170 and ferroptosis-associated genes, which were mainly enriched in ferroptosis and necroptosis. Based on PPI network analysis, 5 hub genes (LCN2, LTF, HP, SLC40A1 and TFRC) were found. These hub genes were involved in iron ion transport and could distinguish T-ALL from normal individuals. Further experimental studies demonstrated that LCN2 was highly expressed in T-ALL, while silencing LCN2 promoted RSL3-induced ferroptotic cell death in T-ALL cells.

CONCLUSION

This study identified novel ferroptosis-associated hub genes, which shed new insights into the underlying mechanism of ferroptosis in T-ALL and also provide promising therapeutic targets for T-ALL.

Basic mechanisms and novel potential therapeutic targets for ferroptosis in acute myeloid leukemia

Ferroptosis is a form of cell death that is regulated by iron and characterized by the buildup of lipid peroxides (LPO) and subsequent rupture of the cell membrane. The molecular mechanisms of ferroptosis involve metabolic pathways related to iron, lipids, and amino acids, which contribute to the production of lipid reactive oxygen species (ROS). In recent years, there has been increasing attention on the occurrence of ferroptosis in various diseases. Ferroptosis has been found to play a crucial role in cardiovascular diseases, digestive diseases, respiratory and immunological diseases, and particularly in malignancies. However, there is still a lack of studies on ferroptosis in acute myeloid leukemia (AML). This paper provides a comprehensive review of the mechanism of ferroptosis and its regulatory molecules and therapeutic agents in AML. It also evaluates the relationship between ferroptosis-related genes (FRGs), non-coding RNAs (ncRNAs), and prognosis to develop prognostic molecular models in AML. The study also explores the association between ferroptosis and immune infiltration in AML, to identify novel potential target regimens for AML.

Development and validation of two redox-related genes associated with prognosis and immune microenvironment in endometrial carcinoma

In recent studies, the tumourigenesis and development of endometrial carcinoma (EC) have been correlated significantly with redox. We aimed to develop and validate a redox-related prognostic model of patients with EC to predict the prognosis and the efficacy of immunotherapy. We downloaded gene expression profiles and clinical information of patients with EC from the Cancer Genome Atlas (TCGA) and the Gene Ontology (GO) dataset. We identified two key differentially expressed redox genes (CYBA and SMPD3) by univariate Cox regression and utilised them to calculate the risk score of all samples. Based on the median of risk scores, we composed low-and high-risk groups and performed correlation analysis with immune cell infiltration and immune checkpoints. Finally, we constructed a nomogram of the prognostic model based on clinical factors and the risk score. We verified the predictive performance using receiver operating characteristic (ROC) and calibration curves. CYBA and SMPD3 were significantly related to the prognosis of patients with EC and used to construct a risk model. There were significant differences in survival, immune cell infiltration and immune checkpoints between the low-and high-risk groups. The nomogram developed with clinical indicators and the risk scores was effective in predicting the prognosis of patients with EC. In this study, a prognostic model constructed based on two redox-related genes (CYBA and SMPD3) were proved to be independent prognostic factors of EC and associated with tumour immune microenvironment. The redox signature genes have the potential to predict the prognosis and the immunotherapy efficacy of patients with EC.

Over-Expressed GATA-1S, the Short Isoform of the Hematopoietic Transcriptional Factor GATA-1, Inhibits Ferroptosis in K562 Myeloid Leukemia Cells by Preventing Lipid Peroxidation

Ferroptosis is a recently recognized form of regulated cell death involving lipid peroxidation. Glutathione peroxidase 4 (GPX4) plays a central role in the regulation of ferroptosis through the suppression of lipid peroxidation generation. Connections have been reported between ferroptosis, lipid metabolism, cancer onset, and drug resistance. Recently, interest has grown in ferroptosis induction as a potential strategy to overcome drug resistance in hematological malignancies. GATA-1 is a key transcriptional factor controlling hematopoiesis-related gene expression. Two GATA-1 isoforms, the full-length protein (GATA-1FL) and a shorter isoform (GATA-1S), are described. A balanced GATA-1FL/GATA-1S ratio helps to control hematopoiesis, with GATA-1S overexpression being associated with hematological malignancies by promoting proliferation and survival pathways in hematopoietic precursors. Recently, optical techniques allowed us to highlight different lipid profiles associated with the expression of GATA-1 isoforms, thus raising the hypothesis that ferroptosis-regulated processes could be involved. Lipidomic and functional analysis were conducted to elucidate these mechanisms. Studies on lipid peroxidation production, cell viability, cell death, and gene expression were used to evaluate the impact of GPX4 inhibition. Here, we provide the first evidence that over-expressed GATA-1S prevents K562 myeloid leukemia cells from lipid peroxidation-induced ferroptosis. Targeting ferroptosis is a promising strategy to overcome chemoresistance. Therefore, our results could provide novel potential therapeutic approaches and targets to overcome drug resistance in hematological malignancies.

Ferrocene-liposome-PEG: a robust ˙OH/lipid peroxide nano-converter for inducing tumor ferroptosis

Ferroptosis induced by iron-dependent accumulation of lipid peroxides (LPOs) has received increasing attention in cancer therapy, especially chemodynamic therapy (CDT). However, the quick annihilation of hydroxyl radicals (˙OH) severely restricts the ˙OH/LPO conversion efficiency, which has become one of the key factors that influences the therapeutic efficacy of ferroptosis-based CDT. Herein, we designed a ˙OH/LPO nano-converter with a high LPO generation efficiency via loading ferrocene (Fc), a green Fenton catalyst, in the phospholipid bilayer of liposome-PEG (Fc-Lp-PEG). Under catalysis with Fc, the over-expressed H₂O₂ in tumors can be decomposed to ˙OH. The generated ˙OH in situ reacts with unsaturated lipids on the liposome, and is converted into LPOs, which spread the lipid peroxidation chain reaction to the remote membranes of cells and organelles, triggering efficient cancer cell ferroptosis. Systematic in vitro and in vivo therapeutic outcomes showed the high tumor inhibition ratio (74.0%) and the low side effects of Fc-Lp-PEG on 4T1 tumor-bearing mice. This novel strategy for improving the ˙OH/LPO conversion efficiency might provide new insights for the clinical development of ferroptosis-based CDT.

Overcoming cancer chemotherapy resistance by the induction of ferroptosis

Development of resistance to chemotherapy in cancer continues to be a major challenge in cancer management. Ferroptosis, a unique type of cell death, is mechanistically and morphologically different from other forms of cell death. Ferroptosis plays a pivotal role in inhibiting tumour growth and has presented new opportunities for treatment of chemotherapy-insensitive tumours in recent years. Emerging studies have suggested that ferroptosis can regulate the therapeutic responses of tumours. Accumulating evidence supports ferroptosis as a potential target for chemotherapy resistance. Pharmacological induction of ferroptosis could reverse drug resistance in tumours. In this review article, we first discuss the key principles of chemotherapeutic resistance in cancer. We then provide a brief overview of the core mechanisms of ferroptosis in cancer chemotherapeutic drug resistance. Finally, we summarise the emerging data that supports the fact that chemotherapy resistance in different types of cancers could be subdued by pharmacologically inducing ferroptosis. This review article suggests that pharmacological induction of ferroptosis by bioactive compounds (ferroptosis inducers) could overcome chemotherapeutic drug resistance. This article also highlights some promising therapeutic avenues that could be used to overcome chemotherapeutic drug resistance in cancer.

Ferroptosis in Cancer Immunotherapy—Implications for Hepatocellular Carcinoma

Ferroptosis is a recently recognized iron-dependent form of non-apoptotic regulated cell death (RCD) characterized by lipid peroxide accumulation to lethal levels. Cancer cells, which show an increased iron dependency to enable rapid growth, seem vulnerable to ferroptosis. There is also increasing evidence that ferroptosis might be immunogenic and therefore could synergize with immunotherapies. Hepatocellular carcinoma (HCC) is the most common primary liver tumor with a low survival rate due to frequent recurrence and limited efficacy of conventional chemotherapies, illustrating the urgent need for novel drug approaches or combinatorial strategies. Immunotherapy is a new treatment approach for advanced HCC patients. In this setting, ferroptosis inducers may have substantial clinical potential. However, there are still many questions to answer before the mystery of ferroptosis is fully unveiled. This review discusses the existing studies and our current understanding regarding the molecular mechanisms of ferroptosis with the goal of enhancing response to immunotherapy of liver cancer. In addition, challenges and opportunities in clinical applications of potential candidates for ferroptosis-driven therapeutic strategies will be summarized. Unraveling the role of ferroptosis in the immune response could benefit the development of promising anti-cancer therapies that overcome drug resistance and prevent tumor metastasis.

Glutamatergic system components as potential biomarkers and therapeutic targets in cancer in non-neural organs

Glutamate is one of the most abundant amino acids in the blood. Besides its role as a neurotransmitter in the brain, it is a key substrate in several metabolic pathways and a primary messenger that acts through its receptors outside the central nervous system (CNS). The two main types of glutamate receptors, ionotropic and metabotropic, are well characterized in CNS and have been recently analyzed for their roles in non-neural organs. Glutamate receptor expression may be particularly important for tumor growth in organs with high concentrations of glutamate and might also influence the propensity of such tumors to set metastases in glutamate-rich organs, such as the liver. The study of glutamate transporters has also acquired relevance in the physiology and pathologies outside the CNS, especially in the field of cancer research. In this review, we address the recent findings about the expression of glutamatergic system components, such as receptors and transporters, their role in the physiology and pathology of cancer in non-neural organs, and their possible use as biomarkers and therapeutic targets.