Crosstalk between Macrophages, T Cells, and Iron Metabolism in Tumor Microenvironment

Targeted ferritinophagy in gastrointestinal cancer: from molecular mechanisms to implications

Gastrointestinal cancer is a significant global health burden, necessitating the development of novel therapeutic strategies. Emerging evidence has highlighted the potential of targeting ferritinophagy as a promising approach for the treatment of gastrointestinal cancer. Ferritinophagy is a form of selective autophagy that is mediated by the nuclear receptor coactivator 4 (NCOA4). This process plays a crucial role in regulating cellular iron homeostasis and has been implicated in various pathological conditions, including cancer. This review discusses the molecular mechanisms underlying ferritinophagy and its relevance to gastrointestinal cancer. Furthermore, we highlight the potential therapeutic implications of targeting ferritinophagy in gastrointestinal cancer. Several approaches have been proposed to modulate ferritinophagy, including small molecule inhibitors and immunotherapeutic strategies. We discuss the advantages and challenges associated with these therapeutic interventions and provide insights into their potential clinical applications.

Angiogenic protein profiling, phytochemical screening and in silico anti-cancer targets validation of stem, leaves, fruit, and seeds of Calotropis procera in human liver and breast cancer cell lines

The main focus of anticancer drug discovery is on developing medications that are gentle on normal cells and should have the ability to target multiple anti-cancer pathways. Liver cancer is becoming a worldwide epidemic due to the highest occurring and reoccurring rate in some countries. Calotropis procera is a xerophytic herbal plant growing wildly in Saudi Arabia. Due to its anti-angiogenic and anticancer capabilities, "C. procera" is a viable option for developing innovative anticancer medicines. However, no study has been done previously, to discover angiogenic and anti-cancer targets which are regulated by C. procera in liver cancer. In this study, leaves, stems, flowers, and seeds of C. procera were used to prepare crude extracts and were fractionated into four solvents of diverse polarities. These bioactivity-guided solvent fractions helped to identify useful compounds with minimal side effects. The phytoconstituents present in the leaves and stem were identified by GC-MS. In silico studies were done to predict the anti-cancer targets by major bioactive constituents present in leaves and stem extracts. A human angiogenesis antibody array was performed to profile novel angiogenic targets. The results from this study showed that C. procera extracts are an ideal anti-cancer remedy with minimum toxicity to normal cells as revealed by zebrafish in vivo toxicity screening assays. The novel antiangiogenic and anticancer targets identified in this study could be explored to design medication against liver cancer.

A ferroptosis-related signature predicts the clinical diagnosis and prognosis, and associates with the immune microenvironment of lung cancer

Targeting ferroptosis-related pathway is a potential strategy for treatment of lung cancer (LC). Consequently, exploration of ferroptosis-related markers is important for treating LC. We collected LC clinical data and mRNA expression profiles from TCGA and GEO database. Ferroptosis-related genes (FRGs) were obtained through FerrDB database. Expression analysis was performed to obtain differentially expressed FRGs. Diagnostic and prognostic models were constructed based on FRGs by LASSO regression, univariate, and multivariate Cox regression analysis, respectively. External verification cohorts GSE72094 and GSE157011 were used for validation. The interrelationship between prognostic risk scores based on FRGs and the tumor immune microenvironment was analyzed. Immunocytochemistry, Western blotting, and RT-qPCR detected the FRGs level. Eighteen FRGs were used for diagnostic models, 8 FRGs were used for prognostic models. The diagnostic model distinguished well between LC and normal samples in training and validation cohorts of TCGA. The prognostic models for TCGA, GSE72094, and GSE157011 cohorts significantly confirmed lower overall survival (OS) in high-risk group, which demonstrated excellent predictive properties of the survival model. Multivariate Cox regression analysis further confirmed risk score was an independent risk factor related with OS. Immunoassays revealed that in high-risk group, a significantly higher proportion of Macrophages_M0, Neutrophils, resting Natural killer cells and activated Mast cells and the level of B7H3, CD112, CD155, B7H5, and ICOSL were increased. In conclusion, diagnostic and prognostic models provided superior diagnostic and predictive power for LC and revealed a potential link between ferroptosis and TIME.

Serum iron element: A novel biomarker for predicting PD-1 immunotherapy efficacy

This study aims to explore the relationship between serum iron by inductively coupled plasma-mass spectrometry (ICP-MS) and the efficacy of immune checkpoint inhibitors (ICIs) and potential mechanism. Totally 113 patients from 233 patients with advanced metastatic lung cancer, esophageal cancer, gastric cancer and colorectal cancer who treated with immunotherapy in Shandong Provincial Hospital were divided into training group (n=68) and validation group (n=45), whose patients were divided into clinical benefit response (CBR) and non-clinical benefit (NCB) by RECIST (v1.1) respectively. We found for the first time that high serum iron level (>1036 μg/L) was a novel biomarker of better PFS (10.13 months vs 7.37 months; p = 0.0015) and OS(16.00 months vs 11.00 months; p = 0.0235) by ROC curve (sensitivity: 78.13 %; Specificity: 80.56 %; p < 0.0001) of CBR (n=32) and NCB (n=36) patients in training group. Interestingly, consistently stable and high serum iron level predicted better efficacy during immunotherapy. Noteworthy, the predictive efficacy of PD-L1 expression was significantly inferior than serum iron (accuracy:63.49% vs 79.41%, p=0.0432), while serum iron detected by spectrophotometry did not predict the efficacy of immunotherapy (p=0.0671) indicating higher sensitivity of ICP-MS. Bioinformatics analysis showed that serum iron could enhance innate immunity and cytokine release and was verified by proteomics that KEGG and GO analysis enriched innate immune and cytokine signaling pathways. Flow cytometry showed that IL-17 (p=0.0002) increased and IL-6 (p=0.0112) decreased after immunotherapy. Based on this, Nomogram with better prediction was constructed by multiple clinical and independent factors. Our results revealed that serum iron is positively associated with ICIs efficacy by enhancing innate immunity and cytokine release in advanced metastatic cancers, and can be a biomarker for predicting ICIs response.

Integrating iron metabolism-related gene signature to evaluate prognosis and immune infiltration in nasopharyngeal carcinoma

BACKGROUND

Dysregulation of iron metabolism has been shown to have significant implications for cancer development. We aimed to investigate the prognostic and immunological significance of iron metabolism-related genes (IMRGs) in nasopharyngeal carcinoma (NPC).

METHODS

Multiple Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets were analyzed to identify key IMRGs associated with prognosis. Additionally, the immunological significance of IMRGs was explored.

RESULTS

A novel risk model was established using the LASSO regression algorithm, incorporating three genes (TFRC, SLC39A14, and ATP6V0D1).This model categorized patients into low and high-risk groups, and Kaplan-Meier analysis revealed significantly shorter progression-free survival for the high-risk group (P < 0.0001). The prognostic model's accuracy was additionally confirmed by employing time-dependent Receiver Operating Characteristic (ROC) curves and conducting Decision Curve Analysis (DCA). High-risk patients were found to correlate with advanced clinical stages, specific tumor microenvironment subtypes, and distinct morphologies. ESTIMATE analysis demonstrated a significant inverse relationship between increased immune, stromal, and ESTIMATE scores and lowered risk score. Immune analysis indicated a negative correlation between high-risk score and the abundance of most tumor-infiltrating immune cells, including dendritic cells, CD8+ T cells, CD4+ T cells, and B cells. This correlation extended to immune checkpoint genes such as PDCD1, CTLA4, TIGIT, LAG3, and BTLA. The protein expression patterns of selected genes in clinical NPC samples were validated through immunohistochemistry.

CONCLUSION

This study presents a prognostic model utilizing IMRGs in NPC, which could assist in assessing patient prognosis and provide insights into new therapeutic targets for NPC.

Advances in Nanodelivery Systems Based on Metabolism Reprogramming Strategies for Enhanced Tumor Therapy

Tumor development and metastasis are closely related to the complexity of the metabolism network. Recently, metabolism reprogramming strategies have attracted much attention in tumor metabolism therapy. Although there is preliminary success of metabolism therapy agents, their therapeutic effects have been restricted by the effective reaching of the tumor sites of drugs. Nanodelivery systems with unique physical properties and elaborate designs can specifically deliver to the tumors. In this review, we first summarize the research progress of nanodelivery systems based on tumor metabolism reprogramming strategies to enhance therapies by depleting glucose, inhibiting glycolysis, depleting lactic acid, inhibiting lipid metabolism, depleting glutamine and glutathione, and disrupting metal metabolisms combined with other therapies, including chemotherapy, radiotherapy, photodynamic therapy, etc. We further discuss in detail the advantages of nanodelivery systems based on tumor metabolism reprogramming strategies for tumor therapy. As well as the opportunities and challenges for integrating nanodelivery systems into tumor metabolism therapy, we analyze the outlook for these emerging areas. This review is expected to improve our understanding of modulating tumor metabolisms for enhanced therapy.

METTL14 drives growth and metastasis of non-small cell lung cancer by regulating pri-miR-93-5p maturation and TXNIP expression

BACKGROUND

Non-small cell lung cancer (NSCLC) is a prevalent and aggressive malignancy responsible for a significant number of cancer-related deaths worldwide. Unraveling the molecular mechanisms governing NSCLC growth and metastasis is crucial for the identification of novel therapeutic targets and the development of effective anti-cancer strategies. One such mechanism of interest is the involvement of METTL14, an RNA methyltransferase implicated in various cellular processes, in NSCLC progression.

OBJECTIVE

The objective of this study was to investigate the role of METTL14 in NSCLC development and metastasis and to elucidate the underlying molecular mechanisms. By understanding the impact of METTL14 on NSCLC pathogenesis, the study aimed to identify potential avenues for targeted therapies in NSCLC treatment.

METHODS

We used bioinformatics and high-throughput transcriptome sequencing analyses to screen regulatory mechanisms affecting NSCLC. The Kaplan-Meier method assessed the correlation between METTL14 expression and the prognosis of NSCLC patients. The effects of manipulated METTL14 on malignant phenotypes of NSCLC cells were examined by colony formation assay, flow cytometry, scratch assay, and Transwell assay. The tumorigenic capacity and metastatic potential of NSCLC cells in vivo were evaluated in nude mice.

RESULTS

METTL14 was overexpressed in NSCLC tissues and cell lines. Its high expression indicated a poor prognosis for NSCLC patients. METTL14 silencing promoted apoptosis and repressed proliferation, migration, and invasion of NSCLC cells. miR-93-5p targeted and inhibited TXNIP. METTL14 increased miR-93-5p expression and matured pri-miR-93-5p through m6A alteration to inhibit TXNIP, thereby inhibiting NSCLC cell apoptosis. By controlling the miR-93-5p/TXNIP axis, METTL14 increased the tumorigenic potential and lung metastasis of NSCLC cells in nude mice.

CONCLUSION

This study revealed a role for METTL14 in the contribution to NSCLC development and metastasis and identified METTL14 as a potential target for NSCLC treatment.

Research progress in nano-drug delivery systems based on the characteristics of the liver cancer microenvironment

The liver cancer has microenvironmental features such as low pH, M2 tumor-associated macrophage enrichment, low oxygen, rich blood supply and susceptibility to hematotropic metastasis, high chemokine expression, enzyme overexpression, high redox level, and strong immunosuppression, which not only promotes the progression of the disease, but also seriously affects the clinical effectiveness of traditional therapeutic approaches. However, nanotechnology, due to its unique advantages of size effect and functionalized modifiability, can be utilized to develop various responsive nano-drug delivery system (NDDS) by using these characteristic signals of the liver cancer microenvironment as a source of stimulation, which in turn can realize the intelligent release of the drug under the specific microenvironment, and significantly increase the concentration of the drug at the target site. Therefore, researchers have designed a series of stimuli-responsive NDDS based on the characteristics of the liver cancer microenvironment, such as hypoxia, weak acidity, and abnormal expression of proteases, and they have been widely investigated for improving anti-tumor therapeutic efficacy and reducing the related side effects. This paper provides a review of the current application and progress of NDDS developed based on the response and regulation of the microenvironment in the treatment of liver cancer, compares the effects of the microenvironment and the NDDS, and provides a reference for building more advanced NDDS.

Nebulized Therapy of Early Orthotopic Lung Cancer by Iron-Based Nanoparticles: Macrophage-Regulated Ferroptosis of Cancer Stem Cells

Cancer stem cells (CSCs) within protumorigenic microlesions are a critical driver in the initiation and progression of early stage lung cancer, where immune cells provide an immunosuppressive niche to strengthen the CSC stemness. As the mutual interactions between CSCs and immune cells are increasingly recognized, regulating the immune cells to identify and effectively eliminate CSCs has recently become one of the most attractive therapeutic options, especially for abundant tumor-associated macrophages (TAMs). Herein, we developed a nebulized nanocatalytic medicine strategy in which iron-based nanoparticle-regulated TAMs effectively target CSC niches and trigger CSC ferroptosis in the early stage of lung cancer. Briefly, the iron-based nanoparticles can effectively accumulate in lung cancer microlesions (minimum 122 μm in diameter) through dextran-mediated TAM targeting by nebulization administration, and as a result, nanoparticle-internalized TAMs can play a predominant role of the iron factory in elevating the iron level surrounding CSC niches and destroying redox equilibrium through downregulating glucose-6-phosphate metabolite following their lysosomal degradation and iron metabolism. The altered microenvironment results in the enhanced sensitivity of CSCs to ferroptosis due to their high expression of the CD44 receptor mediating iron endocytosis. In an orthotopic mouse model of lung cancer, the initiation and progression of early lung cancer are significantly suppressed through ferroptosis-induced stemness reduction of CSCs by nebulization administration. This work presents a nebulized therapeutic strategy for early lung cancer through modulation of communications between TAMs and CSCs, which is expected to be a general approach for regulating primary microlesions and micrometastatic niches of lung cancer.

Cancer-associated fibroblasts impair the cytotoxic function of NK cells in gastric cancer by inducing ferroptosis via iron regulation

As the predominant immunosuppressive component within the tumor microenvironment (TME), cancer-associated fibroblasts (CAFs) inhibit Natural Killer cell (NK cell) activity to promote tumor progression and immune escape; however, the mechanisms of cross-talk between CAFs and NK cells in gastric cancer (GC) remain poorly understood. In this study, we demonstrate that NK cell levels are inversely correlated with CAFs abundance in human GC. CAFs impair the anti-tumor capacity of NK cells by inducing ferroptosis, a cell death process characterized by the accumulation of iron-dependent lipid peroxides. CAFs induce ferroptosis in NK cells by promoting iron overload; conversely, decreased intracellular iron levels protect NK cells against CAF-induced ferroptosis. Mechanistically, CAFs increase the labile iron pool within NK cells via iron export into the TME, which is mediated by the upregulated expression of iron regulatory genes ferroportin1 and hephaestin in CAFs. Moreover, CAF-derived follistatin like protein 1(FSTL1) upregulates NCOA4 expression in NK cells via the DIP2A-P38 pathway, and NCOA4-mediated ferritinophagy is required for CAF-induced NK cell ferroptosis. In a human patient-derived organoid model, functional targeting of CAFs using a combination of deferoxamine and FSTL1-neutralizing antibody significantly alleviate CAF-induced NK cell ferroptosis and boost the cytotoxicity of NK cells against GC. This study demonstrates a novel mechanism of suppression of NK cell activity by CAFs in the TME and presents a potential therapeutic approach to augment the immune response against GC mediated by NK cells.

Crosstalk between ferroptosis and macrophages: potential value for targeted treatment in diseases

Ferroptosis is a newly identified form of programmed cell death that is connected to iron-dependent lipid peroxidization. It involves a variety of physiological processes involving iron metabolism, lipid metabolism, oxidative stress, and biosynthesis of nicotinamide adenine dinucleotide phosphate, glutathione, and coenzyme Q10. So far, it has been discovered to contribute to the pathological process of many diseases, such as myocardial infarction, acute kidney injury, atherosclerosis, and so on. Macrophages are innate immune system cells that regulate metabolism, phagocytize pathogens and dead cells, mediate inflammatory reactions, promote tissue repair, etc. Emerging evidence shows strong associations between macrophages and ferroptosis, which can provide us with a deeper comprehension of the pathological process of diseases and new targets for the treatments. In this review, we summarized the crosstalk between macrophages and ferroptosis and anatomized the application of this association in disease treatments, both non-neoplastic and neoplastic diseases. In addition, we have also addressed problems that remain to be investigated, in the hope of inspiring novel therapeutic strategies for diseases.

Ferroptosis, autophagy, tumor and immunity

Ferroptosis was first proposed in 2012, a new form of cell death. Autophagy plays a crucial role in cell clearance and maintaining homeostasis. Autophagy is involved in the initial step of ferroptosis under the action of histone elements such as NCOA4, RAB7A, and BECN1. Ferroptosis and autophagy are involved in tumor progression, treatment, and drug resistance in the tumor microenvironment. In this review, we described the mechanisms of ferroptosis, autophagy, and tumor and immunotherapy, respectively, and emphasized the relationship between autophagy-related ferroptosis and tumor.

Integrated analysis of single-cell and bulk RNA-sequencing identifies a signature based on T-cell marker genes to predict prognosis and immunotherapy response in bladder cancer

BACKGROUND

T cells have been proven to play important roles in anti-tumor and tumor microenvironment shaping, while these roles have not been explained in bladder cancer (BLCA).

METHODS

Single-cell RNA-sequencing (scRNA-seq) data were downloaded from the gene expression omnibus (GEO) database to screen T-cell marker genes. Bulk RNA-sequencing data and clinical information from BLCA patients were downloaded from the cancer genome atlas (TCGA) database to develop a prognosis signature. We analyzed the association of different risk groups with survival analysis, gene set enrichment analysis (GSEA), tumor mutational burden (TMB), and immunotherapy response.

RESULTS

Based on 192 T-cell marker genes identified by scRNA-seq analysis, we constructed a prognostic signature containing 7 genes in the training cohort, which was further validated in the testing cohort and GEO cohort. The areas under the receiver operating characteristic curve at 1-, 3-, and 5 years were 0.734, 0.742 and 0.726 in the training cohort, 0.697, 0.671 and 0.670 in the testing cohort, 0.702, 0.665 and 0.629 in the GEO cohort, respectively. In addition, we constructed a nomogram based on clinical factors and the risk score of the signature. The low-risk group exhibited higher immune-related pathways, immune cell infiltration and TMB levels. Importantly, immunophenotype score and immunotherapy cohort (IMvigor210) analyses showed that the low-risk group had better immunotherapy response and prognosis.

CONCLUSIONS

Our study reveals a novel prognostic signature based on T-cell marker genes, which provides a new target and theoretical support for BLCA patients.

E2F3 renders an immunosuppressive tumor microenvironment in nasopharyngeal carcinoma: Involvements of the transcription activation of PRC1 and BIRC5

BACKGROUND

E2F transcription factors are well-recognized oncogenic molecules, and their correlation with immune cell infiltration has recently been reported. This work studies the impacts and mechanism of E2F transcription factor 3 (E2F3) in the growth and tumor microenvironment (TME) of nasopharyngeal carcinoma (NPC).

METHODS

Aberrantly expressed transcription factors in NPC were screened by abundant bioinformatics analyses. Gene expression in NPC cells was analyzed by reverse transcription-quantitative polymerase chain reaction and Western blot analyses. Malignant behaviors of NPC cells were analyzed by cell counting kit-8, 5-ethynyl-2'-deoxyuridine labeling, Transwell assays, and xenograft tumor models. TPA-induced THP-1 cells (macrophages) were cultured in the conditioned medium of NPC cells to mimic tumor-associated macrophages (TAMs) in vivo, and these TAMs were cocultured with CD8+ T cells. Regulation of E2F3 on protein regulator of cytokinesis 1 (PRC1) and baculoviral IAP repeat containing 5 (BIRC5) was validated by chromatin immunoprecipitation and luciferase reporter assays.

RESULTS

E2F3 was highly expressed in NPC cells, and its knockdown suppressed malignant behavior and tumorigenic ability of the cells. The E2F3 knockdown condition downregulated M2 cytokines CD163 and interleukin-10 in TAMs, which further enhanced proliferation and activation of the cocultured CD8+ T cells. E2F3 promoted transcription of PRC1 and BRIC5. Furthermore, PRC1 or BRIC5 upregulation in NPC cells restored the malignant properties of NPC cells, reprogrammed the TAMs to M2 phenotype, and suppressed the CD8+ T cell proliferation and activation.

CONCLUSION

This work suggests that E2F3 renders an immunosuppressive TME in NPC by activating PRC1 and BIRC5. Suppression of any member involved might favor tumor elimination.

Targeting the tumor microenvironment: Potential strategy for cancer therapeutics

Cellular and stromal components including tumor cells, immune cells, mesenchymal cells, cancer-linked fibroblasts, and extracellular matrix, constituent tumor microenvironment (TME). TME plays a crucial role in reprogramming tumor initiation, uncontrolled proliferation, invasion and metastasis as well as response to therapeutic modalities. In recent years targeting the TME has developed as a potential strategy for treatment of cancer because of its life-threatening functions in restricting tumor development and modulating responses to standard-of-care medicines. Cold atmospheric plasma, oncolytic viral therapy, bacterial therapy, nano-vaccine, and repurposed pharmaceuticals with combination therapy, antiangiogenic drugs, and immunotherapies are among the most effective therapies directed by TME that have either been clinically authorized or are currently being studied. This article discusses above-mentioned therapies in light of targeting TME. We also cover problems related to the TME-targeted therapies, as well as future insights and practical uses in this rapidly growing field.

Iron deficiency in hepatocellular carcinoma cells induced sorafenib resistance by upregulating HIF-1α to inhibit apoptosis

Sorafenib is the first-line therapeutic agent for hepatocellular carcinoma (HCC), but the drug resistance has become a major impediment. Previously we found that the abnormal iron metabolism in HCC led to iron deficiency, whether it induces sorafenib resistance during the treatment of HCC is not yet disclosed. In this study, we observed the effects of iron deficiency on sorafenib resistance and explored the underlying mechanisms. The results revealed that the killing effects of sorafenib on HCC cells were weakened by iron deficiency but effectively restored by iron re-supplementation. The ferroptosis indicators, including the contents of lipid hydroperoxide (LPO) and malondialdehyde (MDA), the level of intracellular reactive oxygen species (ROS), and the expression of glutathione peroxidase 4 (GPX4), were not significantly changed by iron deficiency in sorafenib-treated HCC cells. However, the sorafenib-induced apoptosis of HCC cells was inhibited by iron deficiency. Notably, the expression of anti-apoptotic protein B-cell lymphoma-2 (BCL-2) was elevated, and the expressions of other apoptotic proteins, BCL2-associated X (Bax), caspase-3, and caspase-9, were inhibited by iron deficiency. Mechanistically, iron deficiency upregulated hypoxia-inducible factor 1 alpha (HIF-1α) to increase BCL-2. Inhibition of HIF-1α suppressed the iron deficiency-induced BCL-2 and sorafenib resistance. In summary, iron deficiency in HCC cells generated sorafenib resistance by increasing HIF-1α and BCL-2, which therefore inhibited the sorafenib-induced apoptosis of HCC cells. These results identified iron deficiency as a new factor of sorafenib resistance in HCC cells, which would be an effective target to alleviate sorafenib resistance.

Glioma-associated microglia/macrophages (GAMs) in glioblastoma: Immune function in the tumor microenvironment and implications for immunotherapy

Glioma is a mixed solid tumor composed of neoplastic and non-neoplastic components. Glioma-associated macrophages and microglia (GAMs) are crucial elements of the glioma tumor microenvironment (TME), regulating tumor growth, invasion, and recurrence. GAMs are also profoundly influenced by glioma cells. Recent studies have revealed the intricate relationship between TME and GAMs. In this updated review, we provide an overview of the interaction between glioma TME and GAMs based on previous studies. We also summarize a series of immunotherapies targeting GAMs, including clinical trials and preclinical studies. Specifically, we discuss the origin of microglia in the central nervous system and the recruitment of GAMs in the glioma background. We also cover the mechanisms through which GAMs regulate various processes associated with glioma development, such as invasiveness, angiogenesis, immunosuppression, recurrence, etc. Overall, GAMs play a significant role in the tumor biology of glioma, and a better understanding of the interaction between GAMs and glioma could catalyze the development of new and effective immunotherapies for this deadly malignancy.

Iron supplementation enhances RSL3-induced ferroptosis to treat naïve and prevent castration-resistant prostate cancer

Prostate cancer (PCa) is a leading cause of death in the male population commonly treated with androgen deprivation therapy that often relapses as androgen-independent and aggressive castration-resistant prostate cancer (CRPC). Ferroptosis is a recently described form of cell death that requires abundant cytosolic labile iron to promote membrane lipid peroxidation and which can be induced by agents that inhibit the glutathione peroxidase-4 activity such as RSL3. Exploiting in vitro and in vivo human and murine PCa models and the multistage transgenic TRAMP model of PCa we show that RSL3 induces ferroptosis in PCa cells and demonstrate for the first time that iron supplementation significantly increases the effect of RSL3 triggering lipid peroxidation, enhanced intracellular stress and leading to cancer cell death. Moreover, the combination with the second generation anti-androgen drug enzalutamide potentiates the effect of the RSL3 + iron combination leading to superior inhibition of PCa and preventing the onset of CRPC in the TRAMP mouse model. These data open new perspectives in the use of pro-ferroptotic approaches alone or in combination with enzalutamide for the treatment of PCa.

Profiling specific cell populations within the inflammatory tumor microenvironment by oscillating-gradient diffusion-weighted MRI

BACKGROUND

The inflammatory tumor microenvironment (TME) is formed by various immune cells, being closely associated with tumorigenesis. Especially, the interaction between tumor-infiltrating T-cells and macrophages has a crucial impact on tumor progression and metastatic spread. The purpose of this study was to investigate whether oscillating-gradient diffusion-weighted MRI (OGSE-DWI) enables a cell size-based discrimination between different cell populations of the TME.

METHODS

Sine-shaped OGSE-DWI was combined with the Imaging Microstructural Parameters Using Limited Spectrally Edited Diffusion (IMPULSED) approach to measure microscale diffusion distances, here relating to cell sizes. The accuracy of IMPULSED-derived cell radii was evaluated using in vitro spheroid models, consisting of either pure cancer cells, macrophages, or T-cells. Subsequently, in vivo experiments aimed to assess changes within the TME and its specific immune cell composition in syngeneic murine breast cancer models with divergent degrees of malignancy (4T1, 67NR) during tumor progression, clodronate liposome-mediated depletion of macrophages, and immune checkpoint inhibitor (ICI) treatment. Ex vivo analysis of IMPULSED-derived cell radii was conducted by immunohistochemical wheat germ agglutinin staining of cell membranes, while intratumoral immune cell composition was analyzed by CD3 and F4/80 co-staining.

RESULTS

OGSE-DWI detected mean cell radii of 8.8±1.3 µm for 4T1, 8.2±1.4 µm for 67NR, 13.0±1.7 for macrophage, and 3.8±1.8 µm for T-cell spheroids. While T-cell infiltration during progression of 4T1 tumors was observed by decreasing mean cell radii from 9.7±1.0 to 5.0±1.5 µm, increasing amount of intratumoral macrophages during progression of 67NR tumors resulted in increasing mean cell radii from 8.9±1.2 to 12.5±1.1 µm. After macrophage depletion, mean cell radii decreased from 6.3±1.7 to 4.4±0.5 µm. T-cell infiltration after ICI treatment was captured by decreasing mean cell radii in both tumor models, with more pronounced effects in the 67NR tumor model.

CONCLUSIONS

OGSE-DWI provides a versatile tool for non-invasive profiling of the inflammatory TME by assessing the dominating cell type T-cells or macrophages.

Effect of tumor microenvironment on ferroptosis: inhibition or promotion

Ferroptosis is a type of lipid peroxidation-induced, iron-dependent programmed cell death. Emerging evidence suggests that ferroptosis is intimately connected to tumorigenesis, development, treatment and plays a major role in tumor immune regulation. This study focused on the connection between ferroptosis and immune regulation, which may offer a theoretical basis for targeting ferroptosis and tumor immunotherapy.

Multi-functional extracellular vesicles: Potentials in cancer immunotherapy

Cancer immunotherapy (CIT) has revolutionized cancer treatment. However, the application of CIT is limited by low response rates and significant individual differences owing to a deficit in 1) immune recognition and 2) immune effector function. Extracellular vesicles (EVs) are cell-derived lipid bilayer-enclosed vesicles that mediate intercellular communication. The specific structure and content of EVs allows for multi-functional modulation of tumor immunity. Given their high biocompatibility, homologous targeting, and permeability across biological barriers, EVs have been evaluated as ideal carriers for promoting the efficacy and specificity of CIT. Herein, we first discuss the role of EVs in regulating tumor immunity and focus on the advantages of using EVs as a therapeutic tool for cancer treatment from a clinical perspective. Further, we outline the current progress in the development of biohybrid EVs for CIT and multi-functional EV-based strategies for overcoming the deficits in tumor immunity. Finally, we discuss the challenges associated with EV-based CIT and future perspectives in the context of ongoing clinical trials involving EV-based therapies, thus offering valuable insights into the future of multi-functional EVs in CIT.

Ferroptosis: a potential therapeutic target for Alzheimer's disease

The most prevalent dementia-causing neurodegenerative condition is Alzheimer's disease (AD). The aberrant buildup of amyloid β and tau hyperphosphorylation are the two most well-known theories about the mechanisms underlying AD development. However, a significant number of pharmacological clinical studies conducted around the world based on the two aforementioned theories have not shown promising outcomes, and AD is still not effectively treated. Ferroptosis, a non-apoptotic programmed cell death defined by the buildup of deadly amounts of iron-dependent lipid peroxides, has received more attention in recent years. A wealth of data is emerging to support the role of iron in the pathophysiology of AD. Cell line and animal studies applying ferroptosis modulators to the treatment of AD have shown encouraging results. Based on these studies, we describe in this review the underlying mechanisms of ferroptosis; the role that ferroptosis plays in AD pathology; and summarise some of the research advances in the treatment of AD with ferroptosis modulators. We hope to contribute to the clinical management of AD.

Combining EZH2 inhibitors with other therapies for solid tumors: more choices for better effects

EZH2 is an epigenetic regulator that methylates lysine 27 on histone H3 (H3K27) and is closely related to the development and metastasis of tumors. It often shows gain-of-function mutations in hematological tumors, while it is often overexpressed in solid tumors. EZH2 inhibitors have shown good efficacy in hematological tumors in clinical trials but poor efficacy in solid tumors. Therefore, current research on EZH2 inhibitors has focused on exploring additional combination strategies in solid tumors. Herein we summarize the combinations and mechanisms of EZH2 inhibitors and other therapies, including immunotherapy, targeted therapy, chemotherapy, radiotherapy, hormone therapy and epigenetic therapy, both in clinical trials and preclinical studies, aiming to provide a reference for better antitumor effects.

L-Citrulline Supplementation Restrains Ferritinophagy-Mediated Ferroptosis to Alleviate Iron Overload-Induced Thymus Oxidative Damage and Immune Dysfunction

L-citrulline (L-cit) is a key intermediate in the urea cycle and is known to possess antioxidant and anti-inflammation characteristics. However, the role of L-cit in ameliorating oxidative damage and immune dysfunction against iron overload in the thymus remains unclear. This study explored the underlying mechanism of the antioxidant and anti-inflammation qualities of L-cit on iron overload induced in the thymus. We reported that L-cit administration could robustly alleviate thymus histological damage and reduce iron deposition, as evidenced by the elevation of the CD8+ T lymphocyte number and antioxidative capacity. Moreover, the NF-κB pathway, NCOA4-mediated ferritinophagy, and ferroptosis were attenuated. We further demonstrated that L-cit supplementation significantly elevated the mTEC1 cells' viability and reversed LDH activity, iron levels, and lipid peroxidation caused by FAC. Importantly, NCOA4 knockdown could reduce the intracellular cytoplasmic ROS, which probably relied on the Nfr2 activation. The results subsequently indicated that NCOA4-mediated ferritinophagy was required for ferroptosis by showing that NCOA4 knockdown reduced ferroptosis and lipid ROS, accompanied with mitochondrial membrane potential elevation. Intriguingly, L-cit treatment significantly inhibited the NF-κB pathway, which might depend on restraining ferritinophagy-mediated ferroptosis. Overall, this study indicated that L-cit might target ferritinophagy-mediated ferroptosis to exert antioxidant and anti-inflammation capacities, which could be a therapeutic strategy against iron overload-induced thymus oxidative damage and immune dysfunction.

Microenvironment immune response induced by tumor ferroptosis—the application of nanomedicine

Ferroptosis is a non-apoptotic regulatory form of cell death that has sparked significant interest and research in cancer treatment and certain small chemical inducers have been used in the clinic. These inducers’s weak water solubility, poor targeting, rapid metabolism; and other undesirable characteristics; however, for therapeutic approaches that combine immunotherapy and ferroptosis, challenges such as medication delivery, the complexity of the tumor microenvironment, and immunosuppression remain. The targeted, low toxicity, and efficient distribution benefits of nanotechnology have considerably enhanced the therapeutic efficacy of combining immunotherapy with ferroptosis. This paper describes the distinct mechanism of ferroptosis in tumor therapy and immunotherapy, as well as the application and benefits of nanotechnology in the combination of tumor immunotherapy and ferroptosis.

The potential applications of microparticles in the diagnosis, treatment, and prognosis of lung cancer

Microparticles (MPs) are 100–1000 nm heterogeneous submicron membranous vesicles derived from various cell types that express surface proteins and antigenic profiles suggestive of their cellular origin. MPs contain a diverse array of bioactive chemicals and surface receptors, including lipids, nucleic acids, and proteins, which are essential for cell-to-cell communication. The tumour microenvironment (TME) is enriched with MPs that can directly affect tumour progression through their interactions with receptors. Liquid biopsy, a minimally invasive test, is a promising alternative to tissue biopsy for the early screening of lung cancer (LC). The diverse biomolecular information from MPs provides a number of potential biomarkers for LC risk assessment, early detection, diagnosis, prognosis, and surveillance. Remodelling the TME, which profoundly influences immunotherapy and clinical outcomes, is an emerging strategy to improve immunotherapy. Tumour-derived MPs can reverse drug resistance and are ideal candidates for the creation of innovative and effective cancer vaccines. This review described the biogenesis and components of MPs and further summarised their main isolation and quantification methods. More importantly, the review presented the clinical application of MPs as predictive biomarkers in cancer diagnosis and prognosis, their role as therapeutic drug carriers, particularly in anti-tumour drug resistance, and their utility as cancer vaccines. Finally, we discussed current challenges that could impede the clinical use of MPs and determined that further studies on the functional roles of MPs in LC are required.

Ferroptosis regulators related scoring system by Gaussian finite mixture model to predict prognosis and immunotherapy efficacy in nasopharyngeal carcinoma

The role of ferroptosis in tumor progression and metastasis has been demonstrated. Nonetheless, potential biological function of ferroptosis regulatory pattern in nasopharyngeal carcinoma (NPC) remains unknown. Ferroptosis regulatory patterns of nasopharyngeal carcinoma samples were evaluated based on 113 ferroptosis regulators and three distinct ferroptosis subtypes were determined by unsupervised clustering. The ferroptosis score (FEP score) was identified to quantify ferroptosis patterns within individual tumors by Gaussian finite mixture model and systematically correlated with representative tumor characteristics. Subtype 1 and subtype 3 were consistent with immune activated phenotype, while subtype 2 was consistent with immune suppressed phenotype. High ferroptosis score, characterized by immune activation and suppression of mRNA based stemness index (mRNAsi) and Epstein-Barr virus (EBV) genes, indicated an immune activated tumor microenvironment (TME) phenotype, with better progression free survival (PFS) and lower risk of recurrence and metastasis. Low ferroptosis score, characterized by activation of Wnt and NF-κB signaling pathways and lack of effective immune infiltration, indicated an immune suppressed tumor microenvironment phenotype and poorer survival. High ferroptosis score was also correlated to enhanced response to immunotherapy, and was confirmed to correlate with therapeutic advantages and clinical benefits in an anti-programmed cell death 1 ligand 1 (PD-L1) immunotherapy cohort. As ferroptosis played a crucial role in the tumor microenvironment’s diversity, assessing the ferroptosis pattern within individual tumor with ferroptosis score could enhance our understanding of tumor microenvironment infiltration characterization and help develop more effective immunotherapy.

The molecular mechanisms of ferroptosis and its role in glioma progression and treatment

Ferroptosis is one of the programmed modes of cell death that has attracted widespread attention recently and is capable of influencing the developmental course and prognosis of many tumors. Glioma is one of the most common primary tumors of the central nervous system, but effective treatment options are very limited. Ferroptosis plays a critical role in the glioma progression, affecting tumor cell proliferation, angiogenesis, tumor necrosis, and shaping the immune-resistant tumor microenvironment. Inducing ferroptosis has emerged as an attractive strategy for glioma. In this paper, we review ferroptosis-related researches on glioma progression and treatment.

A Metabolism-Related Gene Prognostic Index Bridging Metabolic Signatures and Antitumor Immune Cycling in Head and Neck Squamous Cell Carcinoma

Background

In the era of immunotherapy, predictive or prognostic biomarkers for head and neck squamous cell carcinoma (HNSCC) are urgently needed. Metabolic reprogramming in the tumor microenvironment (TME) is a non-negligible reason for the low therapeutic response to immune checkpoint inhibitor (ICI) therapy. We aimed to construct a metabolism-related gene prognostic index (MRGPI) for HNSCC bridging metabolic characteristics and antitumor immune cycling and identified the immunophenotype, genetic alternations, potential targeted inhibitors, and the benefit of immunotherapy in MRGPI-defined subgroups of HNSCC.

Methods

Based on The Cancer Genome Atlas (TCGA) HNSCC dataset (n = 502), metabolism-related hub genes were identified by the weighted gene co-expression network analysis (WGCNA). Seven genes were identified to construct the MRGPI by using the Cox regression method and validated with an HNSCC dataset (n = 270) from the Gene Expression Omnibus (GEO) database. Afterward, the prognostic value, metabolic activities, genetic alternations, gene set enrichment analysis (GSEA), immunophenotype, Connectivity map (cMAP), and benefit of immunotherapy in MRGPI-defined subgroups were analyzed.

Results

The MRGPI was constructed based on HPRT1, AGPAT4, AMY2B, ACADL, CKM, PLA2G2D, and ADA. Patients in the low-MRGPI group had better overall survival than those in the high-MRGPI group, consistent with the results in the GEO cohort (cutoff value = 1.01). Patients with a low MRGPI score display lower metabolic activities and an active antitumor immunity status and more benefit from immunotherapy. In contrast, a higher MRGPI score was correlated with higher metabolic activities, more TP53 mutation rate, lower antitumor immunity ability, an immunosuppressive TME, and less benefit from immunotherapy.

Conclusion

The MRGPI is a promising indicator to distinguish the prognosis, the metabolic, molecular, and immune phenotype, and the benefit from immunotherapy in HNSCC.

Iron Metabolism and Immune Regulation

Iron is a critical element for living cells in terrestrial life. Although iron metabolism is strictly controlled in the body, disturbance of iron homeostasis under certain type of condition leads to innate and adaptive immune response. In innate immunity, iron regulates macrophage polarizations, neutrophils recruitment, and NK cells activity. In adaptive immunity, iron had an effect on the activation and differentiation of Th1, Th2, and Th17 and CTL, and antibody response in B cells. In this review, we focused on iron and immune regulation and listed the specific role of iron in macrophage polarization, T-cell activation, and B-cells antibody response. In addition, correlations between iron and several diseases such as cancer and aging degenerative diseases and some therapeutic strategies targeting those diseases are also discussed.

A Nomogram Based on Circulating CD4+ T Lymphocytes and Lactate Dehydrogenase to Predict Distant Metastasis in Patients with Nasopharyngeal Carcinoma

Purpose

Distant metastasis is the main pattern of treatment failure in nasopharyngeal carcinoma (NPC) in the era of intensity-modulated radiotherapy (IMRT). We aimed to establish and validate a prognostic nomogram to identify patients with a high risk of distant metastasis.

Patients and Methods

A total of 503 patients with nonmetastatic NPC were included in this retrospective study. We established a prognostic nomogram for distant metastasis-free survival (DMFS) based on the Cox proportional hazards model. The predictive discriminative ability and accuracy of the nomogram were assessed with the concordance index (C-index), receiver operating characteristic (ROC) curve, and calibration curve. The nomogram’s clinical utility was also evaluated using decision curve analysis (DCA) and Kaplan–Meier method. The predictive ability of the nomogram was validated in an independent cohort.

Results

The multivariate analysis showed that circulating CD4⁺ T lymphocytes, lactate dehydrogenase (LDH), serum ferritin (SF), and N stage were independent prognostic factors for DMFS. Then, we constructed the nomogram based on these factors. The C-indexes of the nomogram for distant metastasis were 0.763 (95% CI: 0.685–0.841) and 0.760 (95% CI: 0.643–0.877) in the training cohort and validation cohort, respectively, which was higher than the 8th TNM staging system (0.672 and 0.677). The calibration curve showed that the prediction results of the nomogram were in high agreement with the actual observation. The ROC curve indicated that the nomogram had a better predictive ability than TNM staging. The DCA also demonstrated that the nomogram was clinically beneficial. In addition, the patients were classified into two different risk groups (high-risk, low-risk) by the nomogram.

Conclusion

As a supplement to TNM staging, our nomogram could provide a more effective and accurate prognostic prediction of distant metastasis in NPC patients. It has the potential to guide the individualized treatment of patients to improve their survival.

Pre-Clinical Insights into the Iron and Breast Cancer Hypothesis

Population studies, systematic reviews, and meta-analyses have revealed no relationship between iron status and breast cancer, a weak positive association, or a small protective effect of low iron status. However, in those studies, the authors concluded that further investigation was merited. The set of experiments reported here used preclinical models to assess the likely value of further investigation. The effects of iron status on the initiation and promotion stage of mammary carcinogenesis are reported. Using the classical model of cancer initiation in the mammary gland, 7,12 dimethyl-benz[α]anthracene-induced carcinogenesis was unaffected by iron status. Similarly, excess iron intake showed no effect on the promotion stage of 1-methyl-1-nitrosurea-induced mammary carcinogenesis, though iron deficiency exerted a specific inhibitory effect on the carcinogenic process. Though iron-mediated cellular oxidation is frequently cited as a potential mechanism for effects on breast cancer, no evidence of increased oxidative damage to DNA attributable to excess iron intake was found. The reported preclinical data fail to provide convincing evidence that the further evaluation of the iron–breast cancer risk hypotheses is warranted and underscore the value of redefining the referent group in population-based studies of iron–cancer hypotheses in other tissues.

Ferroptosis regulators, especially SQLE, play an important role in prognosis, progression and immune environment of breast cancer

BACKGROUND

Ferroptosis, a new form of programmed cell death, has great potential for cancer treatment. However, the roles of ferroptosis-related (FR) genes in breast cancer (BC) remain elusive.

MATERIALS AND METHODS

Using TCGA database, a novel FR risk signature was constructed through the Lasso regression analysis. Meanwhile, its prognostic value was assessed by a series of survival analyses. Besides, a nomogram was constructed to predict the overall survival rate (OSR) of individual at 1,3,5 year. Four validation cohorts (n = 2248), including METABRIC, GSE58812, GSE20685 and ICGC-KR datasets, were employed to test the prognostic value of FR risk signature. The effects of FR risk signature on BC immune microenvironment were explored by CIBERSORT algorithm and ssGSEA method. The histological expressions of FR risk genes were presented by HPA database. The biofunctions of SQLE were determined by qPCR, MTT, wound-healing and Transwell assays.

RESULTS

We constructed a novel FR risk signature consisting of eight genes. High FR risk led a poor prognosis and was identified as an independent prognostic factor. Besides, A higher proportion of patients with luminal A type was observed in low-risk group (53%), while a higher proportion of patients with basal type in high-risk group (24%). FR risk score could discriminate the prognostic difference of most clinical subgroups, except for M1 stage, HER2 and basal types. Moreover, its prognostic value was successfully validated in other four cohorts. Through immune analyses, we found that the reduced infiltration levels of CD8+ and NK cells, whereas the enhanced activity of antigen presentation process appeared in high FR risk. Then, FR risk score was found to weakly correlate with the expressions of six immune checkpoints. Through the experiments in vitro, we confirmed that overexpression of SQLE could promote, whereas blocking SQLE could inhibit the proliferative, migrative and invasive abilities of BC cells.

CONCLUSIONS

FR risk signature was conducive to BC prognostic assessment. High FR risk level was closely associated with BC immunosuppression, but may not predict ICIs efficacy. Moreover, SQLE was identified as a crucial cancer-promoting gene in BC. Our findings provide new insights into prognostic assessment and molecular mechanism of BC.

Construction of a Ferroptosis-Related Gene Signature for Predicting Survival and Immune Microenvironment in Melanoma Patients

Objective

In this research, we studied the genes associated with ferroptosis to develop a prognostic model and find out an association with tumor immune microenvironment in skin cutaneous melanoma (SKCM) patients.

Methods

To find SKCM-related ferroptosis genes, we used Cox regression and LASSO approach on 60 genes related to ferroptosis and SKCM-related RNA-seq. Following that, a ferroptosis-related gene signature was created. Time-dependent ROC curve and Kaplan–Meier analysis were calculated to determine its capability of prediction. Besides, several assessments were used to evaluate overall survival (OS), accompanied by the creation of a nomogram for the clinicopathologic factors and the ferroptosis-related gene signature we established. We also investigated the relationship between ferroptosis-related gene signature with three immune checkpoints and immune cell infiltration.

Results

Our prognostic model included two genes (ALOX5, CHAC1). In both TCGA and GEO cohorts, OS was lower in high-risk category. Using our gene signature, we can reliably predict OS. Additionally, our gene signature can predict immune cell infiltration and SKCM immunotherapy response.

Conclusion

Our gene signature has shown to be a reliable predictor of OS, reflect the immune microenvironment, and predict the effectiveness of immunotherapy for SKCM patients.

Osteosarcoma in Children: Not Only Chemotherapy

Osteosarcoma (OS) is the most severe bone malignant tumor, responsible for altered osteoid deposition and with a high rate of metastasis. It is characterized by heterogeneity, chemoresistance and its interaction with bone microenvironment. The 5-year survival rate is about 67% for patients with localized OS, while it remains at 20% in case of metastases. The standard therapy for OS patients is represented by neoadjuvant chemotherapy, surgical resection, and adjuvant chemotherapy. The most used chemotherapy regimen for children is the combination of high-dose methotrexate, doxorubicin, and cisplatin. Considered that the necessary administration of high-dose chemotherapy is responsible for a lot of acute and chronic side effects, the identification of novel therapeutic strategies to ameliorate OS outcome and the patients' life expectancy is necessary. In this review we provide an overview on new possible innovative therapeutic strategies in OS.

Identification of Iron Metabolism-Related Genes as Prognostic Indicators for Lower-Grade Glioma

Lower-grade glioma (LGG) is characterized by genetic and transcriptional heterogeneity, and a dismal prognosis. Iron metabolism is considered central for glioma tumorigenesis, tumor progression and tumor microenvironment, although key iron metabolism-related genes are unclear. Here we developed and validated an iron metabolism-related gene signature LGG prognosis. RNA-sequence and clinicopathological data from The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) were downloaded. Prognostic iron metabolism-related genes were screened and used to construct a risk-score model via differential gene expression analysis, univariate Cox analysis, and the Least Absolute Shrinkage and Selection Operator (LASSO)-regression algorithm. All LGG patients were stratified into high- and low-risk groups, based on the risk score. The prognostic significance of the risk-score model in the TCGA and CGGA cohorts was evaluated with Kaplan-Meier (KM) survival and receiver operating characteristic (ROC) curve analysis. Risk- score distributions in subgroups were stratified by age, gender, the World Health Organization (WHO) grade, isocitrate dehydrogenase 1 (IDH1) mutation status, the O6-methylguanine-DNA methyl-transferase (MGMT) promoter-methylation status, and the 1p/19q co-deletion status. Furthermore, a nomogram model with a risk score was developed, and its predictive performance was validated with the TCGA and CGGA cohorts. Additionally, the gene set enrichment analysis (GSEA) identified signaling pathways and pathological processes enriched in the high-risk group. Finally, immune infiltration and immune checkpoint analysis were utilized to investigate the tumor microenvironment characteristics related to the risk score. We identified a prognostic 15-gene iron metabolism-related signature and constructed a risk-score model. High risk scores were associated with an age of > 40, wild-type IDH1, a WHO grade of III, an unmethylated MGMT promoter, and 1p/19q non-codeletion. ROC analysis indicated that the risk-score model accurately predicted 1-, 3-, and 5-year overall survival rates of LGG patients in the both TCGA and CGGA cohorts. KM analysis showed that the high-risk group had a much lower overall survival than the low-risk group (P < 0.0001). The nomogram model showed a strong ability to predict the overall survival of LGG patients in the TCGA and CGGA cohorts. GSEA analysis indicated that inflammatory responses, tumor-associated pathways, and pathological processes were enriched in high-risk group. Moreover, a high risk score correlated with the infiltration immune cells (dendritic cells, macrophages, CD4+ T cells, and B cells) and expression of immune checkpoint (PD1, PDL1, TIM3, and CD48). Our prognostic model was based on iron metabolism-related genes in LGG, can potentially aid in LGG prognosis, and provides potential targets against gliomas.

A Ferroptosis-Related Gene Model Predicts Prognosis and Immune Microenvironment for Cutaneous Melanoma

Background

Cutaneous melanoma is a common but aggressive tumor. Ferroptosis is a recently discovered cell death with important roles in tumor biology. Nevertheless, the prognostic power of ferroptosis-linked genes remained unclear in cutaneous melanoma.

Methods

Cutaneous melanoma patients of TCGA (The Cancer Genome Atlas) were taken as the training cohort while GSE65904 and GSE22153 as the validation cohorts. Multifactor Cox regression model was used to build a prognostic model, and the performance of the model was assessed. Functional enrichment and immune infiltration analysis were used to clarify the mechanisms.

Results

A five ferroptosis-linked gene predictive model was developed. ALOX5 and GCH1 were illustrated as independent predictive factors. Functional assessment showed enriched immune-linked cascades. Immune infiltrating analysis exhibited the distinct immune microenvironment.

Conclusion

Herein, a novel ferroptosis-related gene prognostic model was built in cutaneous melanoma. This model could be used for prognostic prediction, and maybe helpful for the targeted and immunotherapies.

Complex Interactions in Regulation of Haematopoiesis-An Unexplored Iron Mine

Iron is one of the most abundant metals on earth and is vital for the growth and survival of life forms. It is crucial for the functioning of plants and animals as it is an integral component of the photosynthetic apparatus and innumerable proteins and enzymes. It plays a pivotal role in haematopoiesis and affects the development and differentiation of different haematopoietic lineages, apart from its obvious necessity in erythropoiesis. A large amount of iron stores in humans is diverted towards the latter process, as iron is an indispensable component of haemoglobin. This review summarises the important players of iron metabolism and homeostasis that have been discovered in recent years and highlights the overall significance of iron in haematopoiesis. Its role in maintenance of haematopoietic stem cells, influence on differentiation of varied haematopoietic lineages and consequences of iron deficiency/overloading on development and maturation of different groups of haematopoietic cells have been discussed.

Eltrombopag and its iron chelating properties in pediatric acute myeloid leukemia

Pediatric acute myeloid leukemia (AML) represents 20% of total childhood leukemia diagnoses and is characterized by poor prognosis with a long-term survival rate around the 50%, when patients are properly treated. The standard treatment for pediatric AML currently consists in a combination of cytarabine (Ara-C) and antracycline. Iron plays an important role in cancer development and progression. Targeting iron and its metabolism mediators could be a novel therapeutic strategy in cancer.Deferasirox (DFX) inhibits cancer cell proliferation and its use as an antiblastic drug could be suggested. Eltrombopag (ELT), a thrombopoietin receptor agonist used in immunethrombocytopenia, shows anticancer properties related to its emerging iron chelating properties. We compare the anticancer effect of classically used cytarabine with DFX and ELT effects in a pediatric AML cell line, THP-1, in order to identify innovative and more effective therapeutic strategies. ELT and DFX reduce intracellular iron concentration by inhibiting its uptake and by promoting its release. In particular, even though further investigations are needed to better understand the extact underlying action mechanisms, we demonstrated that ELT improves cytarabine antineoplastic activity in pediatric AML cell line.

Iron Released after Cryo-Thermal Therapy Induced M1 Macrophage Polarization, Promoting the Differentiation of CD4+ T Cells into CTLs

Macrophages play critical roles in both innate and adaptive immunity and are known for their high plasticity in response to various external signals. Macrophages are involved in regulating systematic iron homeostasis and they sequester iron by phagocytotic activity, which triggers M1 macrophage polarization and typically exerts antitumor effects. We previously developed a novel cryo-thermal therapy that can induce the mass release of tumor antigens and damage-associated molecular patterns (DAMPs), promoting M1 macrophage polarization. However, that study did not examine whether iron released after cryo-thermal therapy induced M1 macrophage polarization; this question still needed to be addressed. We hypothesized that cryo-thermal therapy would cause the release of a large quantity of iron to augment M1 macrophage polarization due to the disruption of tumor cells and blood vessels, which would further enhance antitumor immunity. In this study, we investigated iron released in primary tumors, the level of iron in splenic macrophages after cryo-thermal therapy and the effect of iron on macrophage polarization and CD4⁺ T cell differentiation in metastatic 4T1 murine mammary carcinoma. We found that a large amount of iron was released after cryo-thermal therapy and could be taken up by splenic macrophages, which further promoted M1 macrophage polarization by inhibiting ERK phosphorylation. Moreover, iron promoted DC maturation, which was possibly mediated by iron-induced M1 macrophages. In addition, iron-induced M1 macrophages and mature DCs promoted the differentiation of CD4⁺ T cells into the CD4 cytolytic T lymphocytes (CTL) subset and inhibited differentiation into Th2 and Th17 cells. This study explains the role of iron in cryo-thermal therapy-induced antitumor immunity from a new perspective.

Identification of Immune-Related LncRNA Pairs for Predicting Prognosis and Immunotherapeutic Response in Head and Neck Squamous Cell Carcinoma

Long noncoding RNAs (lncRNAs) have multiple functions with regard to the cancer immunity response and the tumor microenvironment. The prognosis of head and neck squamous cell carcinoma (HNSCC) is still poor currently, and it may be effective to predict the clinical outcome and immunotherapeutic response of HNSCC by immunogenic analysis. Therefore, by using univariate COX analysis and Lasso Cox regression, we identified a signature consisting of 21 immune-related lncRNA pairs (IRLPs) that predicted clinical outcome and Immunotherapeutic response in HNSCC. Specifically, it was associated with immune cell infiltration (i.e., T cells CD4 memory resting, CD8 T cells, macrophages M0, M2, and NK cells), and more importantly this signature was strongly related with immune checkpoint inhibitors (ICIs) [such as PDCD1 (r = -0.35, P < 0.001), CTLA4 (r = -0.26, P < 0.001), LAG3 (r = -0.22, P < 0.001) and HAVCR2 (r = -0.2, P < 0.001)] and immunotherapy-related biomarkers (MMR and HLA). The present study highlighted the value of the 21 IRLPs signature as a predictor of prognosis and immunotherapeutic response in HNSCC.