Hepatocellular carcinoma (HCC) exhibits pronounced heterogeneity, which significantly limits the effectiveness of precision therapies. A comprehensive understanding of the biological characteristics and molecular mechanisms underlying HCC cell subpopulations is crucial for improving prognostic predictions and refining treatment strategies.

Single-cell RNA sequencing data were obtained from the GEO database and processed using the Seurat R package for quality control, including data filtering, batch effect correction, and dimensionality reduction via PCA and UMAP to visualize cell distribution and identify distinct subpopulations. Cell types were annotated using established marker genes and literature references. The GSVA method was applied to evaluate the activity of 18 programmed cell death pathways. Cell developmental trajectories were reconstructed using Monocle 2 and validated with cytoTRACE to assess differentiation potential. Metabolic pathway activity was analyzed using the scMetabolism package. Bulk RNA sequencing data from the TCGA cohort were integrated to identify prognosis-associated genes through univariate Cox regression. The malignant potential of tumor subpopulations was quantified using GSVA scoring. Weighted gene co-expression network analysis (WGCNA) was employed to identify cuproptosis-related genes. A risk scoring model was constructed using LASSO regression and multivariate Cox regression based on cuproptosis-related genes and marker genes of cuproptosis-characterized tumor cells. The model's performance was validated across TCGA, GEO, and ICGC datasets. Additionally, the relationships between risk scores, clinical characteristics, key signaling pathways, and immunotherapy responses were explored. Finally, a prognostic nomogram was developed to support clinical decision-making.

12 programmed cell death pathways were enriched in tumors, with cuproptosis defining HCC, particularly in the C2 subpopulation. GSVA highlighted high-risk patient enrichment in proliferation, DNA repair, and metabolism, reflecting aggressive malignancy. Developmental trajectory and metabolic analyses confirmed greater stemness and metabolic activity in C2. TCGA linked cuproptosis-related subpopulations to poor prognosis. The risk model stratified patients (validated in TCGA/GEO/ICGC), correlating with clinical grade, T-stage, survival (HR = 2.597, 95%CI 2.051-3.289, P < 0.05). The nomogram showed strong predictive power (C-index = 0.716), aiding clinical decisions.

The C2 subpopulation represents the most malignant subset of HCC cells, with cuproptosis serving as a defining characteristic of this subgroup. The risk scoring and nomogram models based on cuproptosis-related genes offer novel insights and a robust scientific foundation for prognostic prediction and personalized treatment in HCC patients. These findings highlight the potential of targeting cuproptosis and tumor microenvironment interactions to improve therapeutic outcomes in HCC.

Copper is a vital trace metal that facilitates cell proliferation, angiogenesis, and tumour spread. The liver is essential for copper metabolism, hence regulating copper levels is crucial for hepatic health. Hepatocellular carcinoma is a primary liver cancer characterised by a high death rate, and extensive research has shown the substantial impact of copper on its progression. This research primarily examines the molecular mechanisms involved, summarises the regulation of copper homeostasis, and addresses the role of copper metabolism in the promotion and inhibition of hepatocellular carcinoma development. Furthermore, it investigates prospective clinical approaches for targeting copper in the treatment of this disease, intending to establish a theoretical basis for the clinical use of copper in the management of hepatocellular carcinoma.

Cuproptosis, a novel form of regulatory cell death, was investigated in this study for its effects on cuproptosis-associated proteins during gliomas development, offering novel insights into the mechanism of copper ion-based antitumor drugs.

In the present study, bioinformatics and cellular experiments were employed to investigate cuproptosis-related genes (CRGs) in glioma, with a specific focus on SLC31A1.

The study findings indicated that many CRGs (SLC31A1, FDX1, DLST, LIPT1, LIPT2, DLD, NFE2L2, ATP7A, DLAT, GCSH, and ATP7B) were differentially expressed between glioma and non-tumor groups. These genes potentially influence glioma initiation and progression by modulating associated signaling pathways, including those involved in cell cycle regulation, inflammatory responses, and the tumor microenvironment. Survival curve analysis and Cox proportional hazard regression model demonstrated that individuals classified as high-risk exhibited poorer prognosis, suggesting that CRGs possess prognostic capabilities. The assessment of tumor mutational burden indicated that CRGs could serve as biomarkers for predicting the efficacy of immunotherapy in glioma. Further functional analysis of SLC31A1 showed that its elevation was associated with increased glioma cell malignancy, promoting proliferation and migration. Additionally, treatment with the mitotic inhibitor MP-HJ-1b markedly suppressed SLC31A1 expression, consequently inhibiting glioma cell proliferation and migration.

Extensive data analysis indicated that CRGs hold promise as both prognostic markers and potential therapeutic targets for glioma.

Copper is an essential micronutrient in the human body, mainly acting as a crucial cofactor required for a wide range of physiological processes across nearly all cell types. Recent advances revealed that tumor cells seize copper to fulfill their rapid proliferation, metastasis, immune evasion, and so on by reprogramming the copper regulatory network, defined as cuproplasia. Thus, targeting copper chelation to reduce copper levels has been considered a rational tumor therapy strategy. However, overloaded copper ions could be toxic, which leads to the aggregation of lipoylated mitochondrial proteins and the depletion of iron-sulfur clusters, ultimately resulting in cell death, termed cuproptosis. Upon its discovery, cuproptosis has attracted great interest from oncologists, and targeting cuproptosis by copper ionophores exhibits as a potential anti-tumor therapy. In this review, we present the underlying mechanisms involved in cuproplasia and cuproptosis. Additionally, we sum up the chemicals targeting either cuproplasia or cuproptosis for cancer therapy. Further attention should be paid to distinguishing cancer patients who are suitable for targeting cuproplasia or cuproptosis.

Programmed Cell Death (PCD) processes have been suggested to play a role in the development of cancers. The study aimed to investigate the enrichment of different types of PCD and identify important PCD-related genes in Thyroid Carcinoma (THCA).

The whole study is based on transcriptomic analysis and Immunohistochemistry (IHC) experiments. For transcriptomic analysis, the transcriptomic data of THCA (n = 493) and normal thyroid samples (n = 58) was used. The enrichment score of different types of PCD in THCA samples was calculated and the most enriched PCD process was identified. Then the expression of PCD-related genes in control and THCA samples were compared and the association between cuproptosis and characteristics of Tumor Microenvironment (TME) in THCA tissues was explored. IHC experiment was performed to confirm gene expressions in THCA and para-tumor samples.

Enrichment analysis showed that cuproptosis was the most enriched type of PCD process and associated with malignancy in THCA. The expression of a cuproptosis-related gene, CDKN2A, was found and confirmed to be higher in THCA than normal samples and associated with poor outcomes and higher clinical stages of patients with THCA. Moreover, CDKN2A expression was associated with immunosuppressive TME in THCA.

Our findings indicated the important role of cuproptosis and a cuproptosis-related gene, CDKN2A, in the development and progression of THCA, which might provide novel insights into the understanding of pathophysiology of THCA.

The role of copper in tumor progression is thought to be a double-edged sword. Moderate levels of copper promote tumor progression, while excess copper induces a novel form of programmed cell death known as cuproptosis. However, the relationship between lung adenocarcinoma (LUAD) and cuproptosis remains poorly understood. Copper colorimetric assay identified the progression of LUAD simultaneous associated with higher copper accumulation. Single-cell RNA sequencing further identified the activation of unfolded protein response correlates with copper accumulation, particularly the spliced form of XBP1 (XBP1s). XBP1s negatively regulates the protein level of LIPT1 to inhibit LUAD cell death induced by copper-loaded ionophore elesclomol. CUT&Tag-seq and chromosome conformation capture (3 C) experiment showed that XBP1s affect the frequency of MGRN1 promoter-enhancer interactions in various copper environments by forming super-enhancers. Additionally, MGRN1 promotes the ubiquitination and degradation of LIPT1, which in turn supports glycolysis in LUAD cells. In mouse xenograft models, overexpression of XBP1s significantly inhibits the cuproptosis induced by copper ionophores. Co-administration with SEs inhibitor and copper ionophore also markedly reduced tumor volume and growth rate. Our study sheds light on the molecular mechanism by which XBP1s affect the cuproptosis through super-enhancers formation in LUAD and suggested the potential clinical value of copper ionophore as well as a potential biomarker XBP1s for treatment response.

As an essential trace element in the human body, Cu exists in the oxidation states of Cu(II) and Cu(I). The interconversion between these states is closely associated with various redox reactions and plays a pivotal role in cellular respiration regulation, energy metabolism, cell growth regulation, and angiogenesis promotion among other biological processes. As the primary metabolic organ, the liver synthesises and secretes Cu-binding proteins to maintain Cu homeostasis and regulate its metabolism. Studies have increasingly demonstrated that abnormally high or low levels of Cu can negatively affect the immune and metabolic microenvironment within the liver. In this review, we summarise the mechanisms underlying Cu metabolism and its dysregulation and highlight the potential involvement of disrupted Cu metabolism in several liver diseases. Our review provides insights that will help in the future development of novel therapeutic targets focusing on Cu metabolism.

Hepatocellular carcinoma (HCC) is the main phenotype of liver cancer with a poor prognosis. Copper is vital in liver function, and HCC cells rely on it for growth and metastasis, leading to cuproplasia. Excessive copper can induce cell death, termed cuproptosis. Tumor microenvironment (TME) is pivotal in HCC, especially in immunotherapy, and copper is closely related to the TME pathogenesis. However, how these two mechanisms contribute to the TME is intriguing.

We conducted the latest progress literature on cuproplasia and cuproptosis in HCC, and summarized their specific roles in TME and treatment strategies. The mechanisms of cuproplasia and cuproptosis and their relationship and role in TME have been deeply summarized. Cuproplasia fosters TME formation, angiogenesis, and metastasis, whereas cuproptosis may alleviate mitochondrial dysfunction and hypoxic conditions in the TME. Inhibiting cuproplasia and enhancing cuproptosis in HCC are essential for achieving therapeutic efficacy in HCC.

An in-depth analysis of cuproplasia and cuproptosis mechanisms within the TME of HCC unveils their opposing nature and their impact on copper regulation. Grasping the equilibrium between these two factors is crucial for a deeper understanding of HCC mechanisms to shed light on novel directions in treating HCC.

Gastric cancer (GC) is one of the most common tumors; one of the reasons for its poor prognosis is that GC cells can resist normal cell death process and therefore develop distant metastasis. Cuproptosis is a novel type of cell death and a limited number of studies have been conducted on the relationship between cuproptosis-related genes (CRGs) in GC. The purpose of the present study was to establish a prognostic model of CRGs and provide directions for the diagnosis and treatment of GC. Transcriptome and clinical data of patients with GC were collected from The Cancer Genome Atlas and Gene Expression Omnibus datasets. Single sample gene set enrichment analysis (GSEA) and the randomized forest method were used to establish the prognostic model. Kaplan-Meier survival curve, receiver operating characteristics diagram and a nomogram were used to evaluate the reliability of the model. GSEA and gene set variation analysis (GSVA) were used to examine enrichment pathways between high and low risk groups. Finally, immunohistochemical analysis was used to examine ephrin 4 (EFNA4) expression in GC samples and determine the prognosis of patients with GC based on the expression pattern of EFNA4. A group of 7 predictive models (RTKN2, INO80B, EFNA4, ELF2, MUSTN, KRTAP4, and ARHGEF40) was established which were correlated with CRGs. This model can be used as an independent prognostic factor to predict the prognosis of patients with GC. GSEA and GSVA results indicated that high risk patients with GC were mainly associated with the enrichment of ANGIOGENESIS and TGF_BETA_SIGNALING pathways. Finally, EFNA4 expression in GC was significantly higher than that in normal tissues, and patients with GC and high EFNA4 expression exhibited improved prognosis. In conclusion, the prognosis model based on CRGs could be used as the basis for predicting the potential prognosis of patients with GC and provide new insights for the treatment of GC.

Osteosarcoma is one of the most common malignant bone tumours in children. In this study, we aimed to construct a cuproptosis-related lncRNAs signature to predict the prognosis and immune landscape of osteosarcoma patients. Databases from TARGET were used to acquire osteosarcoma patient datasets, which included clinical information and RNA sequencing data. Cuproptosis-related lncRNAs was obtained by correlation analysis. Through univariate Cox regression analysis, prognosis-related lncRNAs were obtained. We used nonnegative matrix factorization clustering to identify potential molecular subgroups with different cuproptosis-related lncRNA expression patterns. The least absolute shrinkage and selection operator algorithm and multivariate Cox regression analysis were used to construct the prognostic signature. The ESTIMATE algorithm, Gene Ontology and Kyoto Encyclopaedia of Genes and Genomes were applied to explore the underlying mechanisms in the immune landscape of osteosarcoma. We used gene set enrichment analysis to compare the different enrichments in the high-risk group and the low-risk group. Furthermore, we predicted the response to targeted drugs in patients with different risk groups. Using multivariable analysis, we developed a risk scoring model based on 7 long noncoding RNAs and calculated two molecular subgroups from osteosarcoma patients from the database. There is a better immune microenvironment in the low-risk group compared to the high-risk group. At the same time, the gene functional enrichment analysis based on the differently expressed genes obtained by grouping showed they were mainly related to immunity, indicating that cuproptosis-related lncRNAs may affect the prognosis of osteosarcoma by regulating immunity. Moreover, these patients in high-risk group were more susceptible to targeted drugs than the low-risk group. We identified a cuproptosis-related lncRNA prognostic signature for osteosarcoma and showed a close connection in terms of immunity. Moreover, we provided some potential targeted drugs for the treatment of osteosarcoma.

Characterized by its high mortality and easy recurrence, hepatocellular carcinoma (HCC) poses significant clinical challenges. The association between copper metabolism and development of cancer has been identified. However, the underlying mechanisms of copper metabolism-related long non-coding RNAs (CMRLs) in HCC remain elusive. To address the gap, our study analyzed the prognostic and immuno-therapeutic value of CMRLs in HCC.

This research utilized The Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) data (n=424) for analysis, applying the "limma" package in R software for differential gene analysis and construction of a prognostic signature. We validated the signature using training and validation groups stochastically divided at a ratio of 1:1 and assessed prognostic value via Kaplan-Meier, C-index, and receiver operating characteristic (ROC) curves. By multivariate Cox regression, independent prognostic indicators were identified, and a nomogram was formulated for survival forecasting. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses elucidated biological pathways, and the immune landscape was examined through multiple algorithms. Finally, drug sensitivity was determined from Genomics of Drug Sensitivity in Cancer (GDSC), with mutation analysis conducted via maftools.

In this study, a predictive model based on four pivotal CMRLs (PRRT3-AS1, AC108752.1, AC092115.3, AL031985.3) significantly associated with HCC progression and prognosis was constructed and validated with the overall survival (OS) prediction area under the curve (AUC) values for 1, 3, and 5 years of 0.718, 0.688, and 0.669, respectively. The calibration curves and C-index values showed a solid prognostic ability of the nomogram. The high-risk group was notably higher than the low-risk group both in OS and tumor mutational burdens (TMBs). Moreover, functional annotation enrichment analysis of CMRLs revealed that the signature was mainly associated with mitotic function, chromosome, kinetochore, cell cycle, and oocyte meiosis. Furthermore, therapeutic drugs, including fluorouracil, afatinib, alpelisib, cedranib, crizotinib, erlotinib, gefitinib, and ipatasertib, were found to induce higher sensitivity in high-risk group.

The prognostic signature consisting of four CMRLs displays an outstanding predictive performance and improves the precision of immuno-oncology.

As a biologically essential transition metal, copper is widely involved in various enzymatic reactions and crucial biological processes in the body. It plays an increasingly important role in maintaining normal cellular metabolism and supporting the growth and development of the human body. As a trace element, copper maintains the dynamic balance of its concentration in body fluids through active homeostatic mechanisms. Both excess and deficiency of copper ions can impair cell function, ultimately leading to cell damage and death. Cuproptosis is a novel form of cell death where copper ions cause cell death by directly binding to the lipoylated components of the citric acid cycle (CAC) in mitochondrial respiration and interfering with the levels of iron-sulfur cluster (Fe-S cluster) proteins, ultimately causing protein toxic stress. Its primary characteristics are Cu2+ concentration dependence and high expression in mitochondrial respiratory cells. Recent research has revealed that, compared to other forms of programmed cell death such as apoptosis, necrosis, and autophagy, cuproptosis has unique morphological and biochemical features. Cuproptosis is associated with the occurrence and development of various diseases, including cancer, neurodegenerative diseases, and cardiovascular diseases. This article focuses on a review of the relevance of cuproptosis in gastric cancer (GC).

The clinical application of the therapeutic approach in myelodysplastic syndromes (MDS) remains an insurmountable challenge for the high propensity for progressing to acute myeloid leukemia and predominantly affecting elderly individuals. Thus, the discovery of molecular mechanisms underlying the regulatory network of different programmed cell death holds great promise for the identification of therapeutic targets and provides insights into new therapeutic avenues. Herein, we found that disulfiram/copper (DSF/Cu) significantly repressed the cell viability, increased reactive oxygen species (ROS) accumulation, destroyed mitochondrial morphology, and altered oxygen consumption rate. Further studies verified that DSF/Cu induces cuproptosis, as evidenced by the depletion of glutathione (GSH), aggregation of lipoylated DLAT, and induced loss of Fe-S cluster-containing proteins, which could be rescued by tetrathiomolybdate and knockdown of ferredoxin 1 (FDX1). Additionally, GSH contributed to the tolerance of DSF/Cu-mediated cuproptosis, while pharmacological chelation of GSH triggered ROS accumulation and sensitized cell death. The xCT-GSH-GPX4 axis is the ideal downstream component of ferroptosis that exerts a powerful protective mechanism. Notably, classical xCT inhibitors were capable of leading to the catastrophic accumulation of ROS and exerting synergistic cell death, while xCT overexpression restored these phenomena. Simvastatin, an inhibitor of HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase, has beneficial effects in repurposing for inhibiting GPX4. Similarly, the combination treatment of DSF/Cu and simvastatin dramatically decreased the expression of GPX4 and Fe-S proteins, ultimately accelerating cell death. Moreover, we identified that the combination treatment of DSF/Cu and simvastatin also had a synergistic antitumor effect in the MDS mouse model, with the reduced GPX4, increased COX-2 and accumulated lipid peroxides. Overall, our study provided insight into developing a novel synergistic strategy to sensitize MDS therapy by targeting ferroptosis and cuproptosis.

Esophageal cancer is a common malignancy of the digestive tract. Despite remarkable advancements in its treatment, the overall prognosis for patients remains poor. Cuproptosis is a form of programmed cell death that affects the malignant progression of tumors. This study aimed to examine the impact of the cuproptosis-associated gene DKC1 on the malignant progression of esophageal cancer.

Clinical and RNA sequencing data of patients with esophageal cancer were extracted from The Cancer Genome Atlas (TCGA). Univariate Cox regression analysis was used to identify the differentially expressed genes related to cuproptosis that are associated with prognosis. We then validated the difference in the expression of DKC1 between tumor and normal tissues via three-dimensional multiomics difference analysis. Subsequently, we investigated the association between DKC1 expression and the tumor microenvironment by employing the TIMER2.0 algorithm, which was further validated in 96 single-cell datasets obtained from the TISCH database. Additionally, the functional role of DKC1 in pancarcinoma was assessed through GSEA. Furthermore, a comprehensive pancancer survival map was constructed, and the expression of DKC1 was verified in various molecular subtypes. By utilizing the CellMiner, GDSC, and CTRP databases, we successfully established a connection between DKC1 and drug sensitivity. Finally, the involvement of DKC1 in the progression of esophageal cancer was investigated through in vivo and in vitro experiments.

In this study, we identified a copper death-related gene, DKC1, in esophageal cancer. Furthermore, we observed varying levels of DKC1 expression across different tumor types. Additionally, we conducted an analysis to determine the correlation between DKC1 expression and clinical features, revealing its association with common cell cycle pathways and multiple metabolic pathways. Notably, high DKC1 expression was found to indicate poor prognosis in patients with various tumors and to influence drug sensitivity. Moreover, our investigation revealed significant associations between DKC1 expression and the expression of molecules involved in immune regulation and infiltration of lymphocyte subtypes. Ultimately, the increased expression of DKC1 in esophageal cancer tissues was verified using clinical tissue samples. Furthermore, DKC1-mediated promotion of esophageal cancer cell proliferation and migration was confirmed through both in vitro and in vivo experiments. Additionally, it is plausible that DKC1 may play a role in the regulation of cuproptosis.

In this study, we conducted a systematic analysis of DKC1 and its regulatory factors and experimentally validated its excellent diagnostic and prognostic abilities in various cancers. Further research indicated that DKC1 may reshape the tumor microenvironment (TME), highlighting the potential of DKC1-based cancer treatment and its usefulness in predicting the response to chemotherapy.

Protein lipoylation, a crucial post-translational modification (PTM), plays a pivotal role in mitochondrial function and emerges as a key player in cell death through cuproptosis. This novel copper-driven cell death pathway is activated by excessive copper ions binding to lipoylated mitochondrial proteins, disrupting energy production and causing lethal protein aggregation and cell death. The intricate relationship among protein lipoylation, cellular energy metabolism, and cuproptosis offers a promising avenue for regulating essential cellular functions. This review focuses on the mechanisms of lipoylation and its significant impact on cell metabolism and cuproptosis, emphasizing the key genes involved and their implications for human diseases. It offers valuable insights into targeting dysregulated cellular metabolism for therapeutic purposes.

Copper is a trace element required by the organism, but once the level of copper exceeds the threshold, it becomes toxic and even causes death. The underlying mechanisms of copper-induced death are inconclusive, with different studies showing different opinions on the mechanism of copper-induced death. Multiple investigations have shown that copper induces oxidative stress, endoplasmic reticulum stress, nucleolar stress, and proteasome inhibition, all of which can result in cell death. The latest research elucidates a copper-dependent death and denominates it as cuproptosis. Cuproptosis takes place through the combination of copper and lipoylated proteins of the tricarboxylic acid cycle, triggering agglomeration of lipoylated proteins and loss of iron-sulfur cluster proteins, leading to proteotoxic stress and ultimately death. Given the toxicity and necessity of copper, abnormal levels of copper lead to diseases such as neurological diseases and cancer. The development of cancer has a high demand for copper, neurological diseases involve the change of copper contents and the binding of copper to proteins. There is a close relationship between these two kinds of diseases and copper. Here, we summarize the mechanisms of copper-related death, and the association between copper and diseases, to better figure out the influence of copper in cell death and diseases, thus advancing the clinical remedy of these diseases.

This study investigated the impact of novel copper ionophores on the prognosis of clear cell renal cell carcinoma (ccRCC) and the tumor microenvironment (TME). The differential expression of 10 cuproptosis and 40 TME-pathway-related genes were measured in 531 tumor samples and 71 adjacent kidney samples in The Cancer Genome Atlas database. A risk score model was constructed with LASSO cox to predict the prognosis of ccRCC patients. Forest plot and function enrichment were used to study the biological function of the key genes in depth. The study found that the risk score model accurately predicted the prognosis of ccRCC patients. Patients with high scores had higher immune responses with a higher proportion of anti-tumor lymphocytes and a lower proportion of immunosuppressive M2-like macrophages. However, the high-score group also exhibited a higher proportion of T follicular helper cells and regulatory T cells. These results suggest that cuproptosis-based therapy may be worth further investigation for the treatment of ccRCC and TME. Subsequently, by using RNAi, we established the stable depletion models of FDX1 and PDHB in ccRCC cell lines 786-O and ACHN. Through CCK8, colony formation, and Transwell assays, we observed that the knockdown of FDX1 and PDHB could significantly reduce the capabilities of proliferation and migration in ccRCC cells. In conclusion, this study illuminates the potential effectiveness of copper ionophores in the treatment of ccRCC, with higher risk scores correlating with better TME immune responses. It sets the stage for future cuproptosis-based therapy research in ccRCC and other cancers, focusing on copper's role in TME.

Background: Currently, there is few literature comprehensively analyzing landscape of cuproptosis-related genes (CRGs) in liver hepatocellular carcinoma (LIHC) with multiple omics approaches. Aims: Using comprehensive analysis, we aim to find out how CRGs works on LIHC. Method: With data from The Cancer Genome Atlas (TCGA) database, we constructed a prognostic prediction model for CGRs using LASSO regression analysis and performed immune infiltration analysis using the same dataset. To validate findings, we utilized RNA expression data from the International Cancer Genome Consortium (ICGC). Furthermore, we analyzed the enrichment and features of CRGs in epithelial cells using single-cell RNA sequencing (scRNA-seq) data. To validate the reliability of findings, we performed several experiments including RT-PCR, cloning formation assay, scratch assay, and Transwell assay. Result: We have constructed a high-precision risk scoring model composed of CRGs for predicting prognosis in TCGA-LIHC. Reliability of the risk prognosis model was confirmed through Kaplan-Meier curve analysis, time-dependent ROC analysis, and multivariate regression analysis. Furthermore, we found knocking down PDSS1 increased sensitivity of LIHC cells to copper ions, and both proliferation and migration abilities were significantly reduced. Finally, we comprehensively characterized the features of CRGs in LIHC through scRNA-seq. Conclusion: In this study, we introduce PDSS1 as a novel CRG in HCC. Utilizing scRNA-seq, we provide a comprehensive landscape of cuproptosis across various cell subtypes within the HCC tumor microenvironment. Furthermore, we detailed the characteristics of high PDSS1-expressing tumor cells, including their distinctive transcription factors, metabolic profiles, and interactions with different subtypes within the tumor microenvironment. This work not only elucidated the role of PDSS1 in HCC but also enhanced our understanding of cuproptosis dynamics during tumor progression.

Cuproptosis, a type of regulated cell death that was recently identified, has been linked to the development of a variety of diseases, among them being cancers. Nevertheless, the prognostic significance and therapeutic implications of the cuproptosis potential index in hepatocellular carcinoma (HCC) remain uncertain.

Single-sample gene set enrichment analysis (ssGSEA) and Weighted Gene Co-expression Network Analysis (WGCNA) methodology was conducted to ascertain the identification of modular genes that are closely linked to cuproptosis. In addition, the gene signature indicative of prognosis was formulated by employing univariate Cox regression analysis in conjunction with a random forest algorithm. The efficacy of this gene signature in predicting outcomes was confirmed through validation in both The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) datasets. Furthermore, a study was undertaken to evaluate the association between the risk score and various clinical-pathological characteristics, explore the biological processes linked to the gene signature, and analyze tumor mutational burden and somatic mutations. Lastly, potential drugs targeting the identified gene signature were identified through screening.

The results of our comprehensive analysis across multiple cancer types demonstrated a positive correlation between an elevated cuproptosis potential index (CPI) and an accelerated rate of tumor progression. Furthermore, employing the WGCNA technique, we successfully identified 640 genes associated with cuproptosis. Among these genes, we meticulously screened and validated a seven-gene signature (TCOF1, NOP58, TMEM69, FARSB, DHX37, SLC16A3, and CBX2) that exhibited substantial prognostic significance. Using the median risk score, the division of HCC patients into cohorts with high- and low-risk highlighted significant disparities in survival results, wherein the group with higher risk exhibited a less favorable overall survival. The risk score exhibited commendable predictive efficacy. Moreover, the in vitro knockdown of FARSB significantly hindered cell viability, induced G1 phase arrest, increased apoptosis, and impaired migration in HepG2 and Huh7 cells.

Our research has successfully identified a strong seven-gene signature linked to cuproptosis, which could be utilized for prognostic evaluation and risk stratification in patients with HCC. Furthermore, the discovered gene signature, coupled with the functional analysis of FARSB, presents promising prospects as potential targets for therapeutic interventions in HCC.

Ferroptosis and cuproptosis are recently discovered forms of cell death that have gained interest as potential cancer treatments, particularly for hepatocellular carcinoma. Long non-coding RNAs (lncRNAs) influence cancer cell activity by interacting with various nucleic acids and proteins. However, the role of ferroptosis and cuproptosis-related lncRNAs (FCRLs) in cancer remains underexplored. Ferroptosis and cuproptosis scores for each sample were assessed using Gene Set Variation Analysis (GSVA). Weighted correlation network analysis identified the FCRLs most relevant to our study. A risk model based on FCRLs was developed to categorize patients into high-risk and low-risk groups. We then compared overall survival (OS), tumor immune microenvironment, and clinical characteristics between these groups. The IPS score and ImmuCellAI webpage were used to predict the association between FCRL-related signatures and immunotherapy response. Finally, we validated the accuracy of FCRLs in hepatocellular carcinoma cell lines using induction agents (elesclomol and erastin). Patients in different risk subgroups showed significant differences in OS, immune cell infiltration, pathway activity, and clinical characteristics. Cellular assays revealed significant changes in the expression of AC019080.5, AC145207.5, MIR210HG, and LINC01063 in HCC cell lines following the addition of ferroptosis and cuproptosis inducers. We created a signature of four FCRLs that accurately predicted survival in HCC patients, laid the foundation for basic research related to ferroptosis and cuproptosis in hepatocellular carcinoma, and provided therapeutic recommendations for HCC patients.

Recent studies have highlighted the biological significance of cuproptosis in disease occurrence and development. However, it remains unclear whether cuproptosis signaling also has potential impacts on tumor initiation and prognosis of gastric cancer (GC). In this study, 16 cuproptosis-related genes (CRGs) transcriptional profiles were harnessed to perform the regularized latent variable model-based clustering in GC. A cuproptosis signature risk scoring (CSRS) scheme, based on a weighted sum of principle components of the CRGs, was used to evaluate the prognosis and risk of individual tumors of GC. Four distinct cuproptosis signature-based clusters, characterized by differential expression patterns of CRGs, were identified among 1136 GC samples across three independent databases. The four clusters were also associated with different clinical outcomes and tumor immune contexture. Based on the CSRS, GC patients can be divided into CSRS-High and CSRS-Low subtypes. We found that DBT, MTF1, and ATP7A were significantly elevated in the CSRS-High subtype, while SLC31A1, GCSH, LIAS, DLAT, FDX1, DLD, and PDHA1 were increased in the CSRS-Low subtype. Patients with CSRS-Low score were characterized by prolonged survival time. Further analysis indicated that CSRS-Low score also correlated with greater tumor mutation burden (TMB) and higher mutation rates of significantly mutated genes (SMG) in GC. In addition, the CSRS-High subtype harbored more significantly amplified focal regions related to tumorigenesis (3q27.1, 12p12.1, 11q13.3, etc.) than the CSRS-Low tumors. Drug sensitivity analyses revealed the potential compounds for the treatment of gastric cancer with CSRS-High score, which were experimentally validated using GC cells. This study highlights that cuproptosis signature-based subtyping is significantly associated with different clinical features and molecular landscape of GC. Quantitative evaluation of the CSRS of individual tumors will strengthen our understanding of the occurrence and development of cuproptosis and the treatment progress of GC.

Copper metabolism dysfunction has been found to be associated with the progression of various malignant tumors. The aim of this study is to explore the prognostic value of copper metabolism-related genes (CMRGs) in hepatocellular carcinoma (HCC) and their impact on the immune microenvironment.

We identified differentially expressed CMRGs in cancer and adjacent samples of HCC from The Cancer Genome Atlas (TCGA). Consensus clustering was performed to distinguish subgroups, and TIMER and CIBERSORT were applied to analyze the tumor immune microenvironment (TIME). We used the least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis to establish a prognostic risk model for CMRGs. Gene set enrichment analysis (GSEA) was performed to elucidate potential signaling mechanisms associated with the risk group, as well as to determine and compare the tumor mutation burden (TMB), immune cell infiltration levels, and immune checkpoint of the identified risk groups.

Two subgroups with significantly different survival rates were identified, with a better prognosis associated with high immune scores, high abundance of immune-infiltrating cells, and a relatively higher immune status. A prognostic risk model based on five CMRGs was constructed, which showed significant prognostic value. When combined with clinical feature column charts, this model can predict the prognosis of patients with HCC. Functional enrichment analysis showed that the low-risk group was enriched in a large number of metabolic pathways, while the high and low-risk groups exhibited different TMB and differential expression of immune checkpoint genes. The established model was validated in an independent International Cancer Genome Consortium (ICGC) dataset.

The results indicate that the expression of CMRGs is associated with the prognosis of HCC and the tumor microenvironment, and can serve as a predictive indicator for evaluating the prognosis of HCC.

Cancer immunotherapy, such as immune checkpoint blockade (ICB), has emerged as a groundbreaking approach for effective cancer treatment. Despite its considerable potential, clinical studies have indicated that the current response rate to cancer immunotherapy is suboptimal, primarily attributed to low immunogenicity in certain types of malignant tumors. Immunogenic cell death (ICD) represents a form of regulated cell death (RCD) capable of enhancing tumor immunogenicity and activating tumor-specific innate and adaptive immune responses in immunocompetent hosts. Therefore, gaining a deeper understanding of ICD and its evolution is crucial for developing more effective cancer therapeutic strategies. This review focuses exclusively on both historical and recent discoveries related to ICD modes and their mechanistic insights, particularly within the context of cancer immunotherapy. Our recent findings are also highlighted, revealing a mode of ICD induction facilitated by atypical interferon (IFN)-stimulated genes (ISGs), including polo-like kinase 2 (PLK2), during hyperactive type I IFN signaling. The review concludes by discussing the therapeutic potential of ICD, with special attention to its relevance in both preclinical and clinical settings within the field of cancer immunotherapy.

Recent research has hinted at a potential connection between silicosis, a fibrotic lung disease caused by exposure to crystalline silica particles, and cuproptosis. The aim of the study was to explore how cuproptosis-related genes (CRGs) may influence the development of silicosis and elucidate the underlying mechanisms. An analysis of genes associated with both silicosis and cuproptosis was conducted. Key gene identification was achieved through the application of two machine learning techniques. Additionally, the correlation between these key genes and immune cell populations was explored and the critical pathways were discerned. To corroborate our findings, the expression of key genes was verified in both a publicly available silica-induced mouse model and our own silicosis mouse model. A total of 12 differentially expressed CRGs associated with silicosis were identified. Further analysis resulted in the identification of 6 CRGs, namely LOX, SPARC, MOXD1, ALB, MT-CO2, and AOC2. Elevated immune cell infiltration of CD8 T cells, regulatory T cells, M0 macrophages, and neutrophils in silicosis patients compared to healthy controls was indicated. Validation in a silica-induced pulmonary fibrosis mouse model supported SPARC and MT-CO2 as potential signature genes for the prediction of silicosis. These findings highlight a strong association between silicosis and cuproptosis. Among CRGs, LOX, SPARC, MOXD1, ALB, MT-CO2, and AOC2 emerged as pivotal players in the context of silicosis by modulating CD8 T cells, regulatory T cells, M0 macrophages, and neutrophils.

Breast cancer arises from the malignant transformation of mammary epithelial cells under the influence of various carcinogenic factors, leading to a gradual increase in its prevalence. This disease has become the leading cause of mortality among female malignancies, posing a significant threat to the health of women. The timely identification of breast cancer remains challenging, often resulting in diagnosis at the advanced stages of the disease. Conventional therapeutic approaches, such as surgical excision, chemotherapy and radiotherapy, exhibit limited efficacy in controlling the progression and metastasis of the disease. Regulated cell death (RCD), a process essential for physiological tissue cell renewal, occurs within the body independently of external influences. In the context of cancer, research on RCD primarily focuses on cuproptosis, ferroptosis and pyroptosis. Mounting evidence suggests a marked association between these specific forms of RCD, and the onset and progression of breast cancer. For example, a cuproptosis vector can effectively bind copper ions to induce cuproptosis in breast cancer cells, thereby hindering their proliferation. Additionally, the expression of ferroptosis‑related genes can enhance the sensitivity of breast cancer cells to chemotherapy. Likewise, pyroptosis‑related proteins not only participate in pyroptosis, but also regulate the tumor microenvironment, ultimately leading to the death of breast cancer cells. The present review discusses the unique regulatory mechanisms of cuproptosis, ferroptosis and pyroptosis in breast cancer, and the mechanisms through which they are affected by conventional cancer drugs. Furthermore, it provides a comprehensive overview of the significance of these forms of RCD in modulating the efficacy of chemotherapy and highlights their shared characteristics. This knowledge may provide novel avenues for both clinical interventions and fundamental research in the context of breast cancer.

Cuproptosis is a novel form of cell death that exhibits close association with mitochondrial respiration and occurs through distinct mechanisms compared to previously characterized forms of cell death. However, the precise impact of cuproptosis-associated genes (CAGs) on prognosis, immune profiles, and treatment efficacy in hepatocellular carcinomas (HCC) remains poorly understood.

A comprehensive analysis of CAGs in hepatocellular carcinoma (HCC) prognosis was conducted using genomic data from HCC patients. Consensus clustering analysis was performed to determine molecular subtypes related to cuproptosis in HCC. The single-sample gene set enrichment analysis (ssGSEA) algorithm was applied to quantify the infiltration levels of immune cells, while the "ESTIMATE" package was employed to calculate tumor purity, stromal scores, and immune scores in the tumor microenvironment (TME). Principal component analysis (PCA) algorithm was utilized to construct a risk score related to CAGs. Finally, CCK8, wound healing, Transwell migration/invasion, EDU and xenograft model were employed to explore the potential oncogenic role of MTF1.

Three distinct patterns of cuproptosis modification were identified, each associated with unique functional enrichments, clinical characteristics, immune cell infiltration, immune checkpoints, tumor microenvironment (TME), and prognosis. A CAGs-related risk score (Cuscore) was developed to predict prognosis in TCGA and validated in GSE76427 and ICGC datasets. Notably, patients with a low Cuscore had better prognoses and were more likely to benefit from immunotherapy.Additionally, the high Cuscore group in HCC also revealed three potential therapeutic targets (TUBA1B, CDC25B, and CSNK2A1) as well as several therapeutic compounds. Moreover, the experiment measured the expression levels of six prognosis-related CAGs, wherein knockdown of MTF1 exhibited suppression of proliferation, invasion, and migration formation in HCC cell lines.

The findings have enhanced our comprehension of the cuproptosis characteristics in HCC, and stratification based on CuScore may potentially enhance the prediction of patients' prognosis and facilitate the development of effective and innovative treatment strategies.

Copper, a vital trace element, orchestrates diverse cellular processes ranging from energy production to antioxidant defense and angiogenesis. Copper metabolism and cuproptosis are closely linked in the context of human diseases, with a particular focus on cancer. Cuproptosis refers to a specific type of copper-mediated cell death or copper toxicity triggered by disruptions in copper metabolism within the cells. This phenomenon encompasses a spectrum of mechanisms, such as oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress, and perturbations in metal ion equilibrium. Mechanistically, cuproptosis is driven by copper binding to the lipoylated enzymes within the tricarboxylic acid (TCA) cycle. This interaction participates in protein aggregation and proteotoxic stress, ultimately culminating in cell death. Targeting copper metabolism and its associated pathways in cancer cells hold therapeutic potential by selectively targeting and eliminating cancerous cells. Strategies to modulate copper levels, enhance copper excretion, or interfere with cuproptotic pathways are being explored to identify novel therapeutic targets for cancer therapy and improve patient outcomes. Understanding the relationship between cuproptosis and copper metabolism in human malignancies remains an active area of research. This review provides a comprehensive overview of the association among copper metabolism, copper homeostasis, and carcinogenesis, explicitly emphasizing the cuproptosis mechanism and its implications for cancer pathogenesis. Additionally, we emphasize the therapeutic aspects of targeting copper and cuproptosis for cancer treatment.

Numerous nutritional factors increase the risk of hepatocellular carcinoma (HCC) development. The dysregulation of zinc, copper, and selenium homeostasis is associated with the occurrence of HCC. The impairment of the homeostasis of these essential trace elements results in oxidative stress, DNA damage, cell cycle progression, and angiogenesis, finally leading to hepatocarcinogenesis. These essential trace elements can affect the microenvironment in HCC. The carrier proteins for zinc and copper and selenium-containing enzymes play important roles in the prevention or progression of HCC. These trace elements enhance or alleviate the chemosensitivity of anticancer agents in patients with HCC. The zinc, copper, or selenium may affect the homeostasis of other trace elements with each other. Novel types of cell death including ferropotosis and cupropotosis are also associated with hepatocarcinogenesis. Therapeutic strategies for HCC that target these carrier proteins for zinc and copper or selenium-containing enzymes have been developed in in vitro and in vivo studies. The use of zinc-, copper- or selenium-nanoparticles has been considered as novel therapeutic agents for HCC. These results indicate that zinc, copper, and selenium may become promising therapeutic targets in patients with HCC. The clinical application of these agents is an urgent unmet requirement. This review article highlights the correlation between the dysregulation of the homeostasis of these essential trace elements and the development of HCC and summarizes the current trends on the roles of these essential trace elements in the pathogenesis of hepatocarcinogenesis.

Cuprotosis, an emerging mode of cell death, has recently caught the attention of researchers worldwide. However, its impact on low-grade glioma (LGG) patients has not been fully explored. To gain a deeper insight into the relationship between cuprotosis and LGG patients' prognosis, we conducted this study in which LGG patients were divided into two clusters based on the expression of 18 cuprotosis-related genes. We found that LGG patients in cluster A had better prognosis than those in cluster B. The two clusters also differed in terms of immune cell infiltration and biological functions. Moreover, we identified differentially expressed genes (DEGs) between the two clusters and developed a cuprotosis-related prognostic signature through the least absolute shrinkage and selection operator (LASSO) analysis in the TCGA training cohort. This signature divided LGG patients into high- and low-risk groups, with the high-risk group having significantly shorter overall survival (OS) time than the low-risk group. Its predictive reliability for prognosis in LGG patients was confirmed by the TCGA internal validation cohort, CGGA325 cohort and CGGA693 cohort. Additionally, a nomogram was used to predict the 1-, 3-, and 5-year OS rates of each patient. The analysis of immune checkpoints and tumor mutation burden (TMB) has revealed that individuals belonging to high-risk groups have a greater chance of benefiting from immunotherapy. Functional experiments confirmed that interfering with the signature gene TNFRSF11B inhibited LGG cell proliferation and migration. Overall, this study shed light on the importance of cuprotosis in LGG patient prognosis. The cuprotosis-related prognostic signature is a reliable predictor for patient outcomes and immunotherapeutic response and can help to develop new therapies for LGG.

Renal cell carcinoma (RCC) is the predominant form of malignant kidney cancer. Sunitinib, a primary treatment for advanced, inoperable, recurrent, or metastatic RCC, has shown effectiveness in some patients but is increasingly limited by drug resistance. Recently identified cuproptosis, a copper-ion-dependent form of programmed cell death, holds promise in combating cancer, particularly drug-resistant types. However, its effectiveness in treating drug resistant RCC remains to be determined. Exploring cuproptosis's regulatory mechanisms could enhance RCC treatment strategies. Our analysis of data from the GEO and TCGA databases showed that the cuproptosis-related gene DBT is markedly under expressed in RCC tissues, correlating with worse prognosis and disease progression. In our study, we investigated copper CRGs in ccRCC, noting substantial expression differences, particularly in advanced-stage tumors. We established a connection between CRG expression levels and patient survival, positioning CRGs as potential therapeutic targets for ccRCC. In drug resistant RCC cases, we found distinct expression patterns for DBT and GLS CRGs, linked to treatment resistance. Our experiments demonstrated that increasing DBT expression significantly reduces RCC cell growth and spread, underscoring its potential as a therapeutic target. This research sheds new light on the role of CRGs in ccRCC and their impact on drug resistance.

The pyruvate dehydrogenase E1 subunit β (PDHB) gene which regulates energy metabolism is located in mitochondria. However, few studies have elucidated the role and mechanism of PDHB in different cancers.

To comprehensive pan-cancer analysis of PDHB was performed based on bioinformatics approaches to explore its tumor diagnostic and prognostic value and tumor immune relevance in cancer. In vitro experiments were performed to examine the biological regulation of PDHB in liver cancer.

Pan-cancer data related to PDHB were obtained from the Cancer Genome Atlas (TCGA) database. Analysis of the gene expression profiles of PDHB was based on TCGA and Genotype Tissue Expression Dataset databases. Cox regression analysis and Kaplan-Meier methods were used to assess the correlation between PDHB expression and survival prognosis in cancer patients. The correlation between PDHB and receiver operating characteristic diagnostic curve, clinicopathological staging, somatic mutation, tumor mutation burden (TMB), microsatellite instability (MSI), DNA methylation, and drug susceptibility in pan-cancer was also analyzed. Various algorithms were used to analyze the correlation between PDHB and immune cell infiltration and tumor chemotaxis environment, as well as the co-expression analysis of PDHB and immune checkpoint (ICP) genes. The expression and functional phenotype of PDHB in single tumor cells were studied by single-cell sequencing, and the functional enrichment analysis of PDHB-related genes was performed. The study also validated the level of mRNA or protein expression of PDHB in several cancers. Finally, in vitro experiments verified the regulatory effect of PDHB on the proliferation, migration, and invasion of liver cancer.

PDHB was significantly and differently expressed in most cancers. PDHB was significantly associated with prognosis in patients with a wide range of cancers, including kidney renal clear cell carcinoma, kidney renal papillary cell carcinoma, breast invasive carcinoma, and brain lower grade glioma. In some cancers, PDHB expression was clearly associated with gene mutations, clinicopathological stages, and expression of TMB, MSI, and ICP genes. The expression of PDHB was closely related to the infiltration of multiple immune cells in the immune microenvironment and the regulation of tumor chemotaxis environment. In addition, single-cell sequencing results showed that PDHB correlated with different biological phenotypes of multiple cancer single cells. This study further demonstrated that down-regulation of PDHB expression inhibited the proliferation, migration, and invasion functions of hepatoma cells.

As a member of pan-cancer, PDHB may be a novel cancer marker with potential value in diagnosing cancer, predicting prognosis, and in targeted therapy.

According to statistics, the incidence of liver cancer is increasing yearly, and effective treatment of liver cancer is imminent. For early liver cancer, resection surgery is currently the most effective treatment. However, resection does not treat the disease in advanced patients, so finding a method with a better prognosis is necessary. In recent years, ferroptosis and cuproptosis have been gradually defined, and related studies have proved that they show excellent results in the therapy of liver cancer. Cuproptosis is a new form of cell death, and the use of cuproptosis combined with ferroptosis to inhibit the production of hepatocellular carcinoma cells has good development prospects and is worthy of in-depth discussion by researchers. In this review, we summarize the research progress on cuproptosis combined with ferroptosis in treating liver cancer, analyze the value of cuproptosis and ferroptosis in the immune of liver cancer, and propose potential pathways in oncotherapy with the combination of cuproptosis and ferroptosis, which can provide background knowledge for subsequent related research.

Current immunotherapy for prostate cancer is still in the stage of clinical trials. This delay is thought to be caused by an unclear regulatory mechanism of the immune microenvironment, which makes it impossible to distinguish patients suitable for immunotherapy. Cuprotosis may be related to the heterogeneity of immune microenvironment, which was regarded as a new copper-dependent cell death mode, was proposed, and gain attention. We explored for the first time the relationship between cuprotosis and the immune microenvironment of prostate cancer and constructed cuprotosis score. RNA sequencing data sets for prostate cancer were downloaded from public databases. Consensus clustering was applied to distinguish cuprotosis phenotype based on the expression of cuproptosis-related genes (CRGs) identified as prognostic factors. Genomic phenotypes of CRG clusters were depicted via consensus clustering. Cuprotosis score was established on the basis of differentially expressed genes (DEGs) identified as prognostic factors via principal component analysis. Cuprotosis score = the first principal component of prognostic factors + the second principal component of prognostic factors. The value of cuproptosis score in predicting prognosis and immunotherapy response was evaluated. PDHA1 (HR = 3.86, P < 0.001) and GLS (HR = 1.75, P = 0.018) were risk factors for prognosis of prostate cancer patients, while DBT (HR = 0.66, P = 0.048) was a favorable factor for prognosis of prostate cancer patients. CRG clusters had different prognosis and immune cell infiltration. So as gene clusters. Prostate cancer patients with low cuprotosis score showed better prognosis for biochemical relapse-free survival. Cuprotosis score is accompanied with high immune score and Gleason score. As cuprotosis genes, PDHA1, GLS, and DBT were identified as independent prognostic factors of prostate cancer. Cuprotosis score was established via principal component analysis of PDHA1, GLS, and DBT, which can be used as a predictor of prognosis and immunotherapy response of prostate cancer patients, and can characterize immune cells infiltration in tumors. Cuproptosis was involved in the regulation of immune microenvironment, which may depend on the effect of tricarboxylic acid cycle. Our study provided clues to reveal the relationship between copper death and immune microenvironment, highlighted the clinical significance of cuproptosis, and provided a reference for the development of personalized immunotherapy.

Characterizing the two- and three-dimensional distribution of trace metals in biological specimens is key to better understand their role in biological processes. Iron (Fe) is of particular interest in these trace metals due to its widespread role in maintaining cellular health and preventing disease. X-ray fluorescence microscopy (XFM) is emerging as the method of choice for investigators to interrogate the cellular and subcellular distribution of Fe. XFM utilizes the intrinsic X-ray fluorescence properties of each element to produce quantitative 2D and 3D distributions of trace metals within a sample. Herein, methods for sample preparation of cells and tissue for the determination of Fe distribution by XFM are described.

Ferroptosis and cuproptosis play a crucial role in the progression and dissemination of hepatocellular carcinoma (HCC). The primary objective of this study was to develop a unique scoring system for predicting the prognosis and immunological landscape of HCC based on ferroptosis-related genes (FRGs) and cuproptosis-related genes (CRGs).

As the training cohort, we assembled a novel HCC cohort by merging gene expression data and clinical data from The Cancer Genome Atlas (TCGA) database, and Gene Expression Omnibus (GEO) database. The validation cohort consisted of 230 HCC cases taken from the International Cancer Genome Consortium (ICGC) database. Multiple genomic characteristics, such as tumor mutation burden (TMB), and copy number variations were analyzed concurrently. On the basis of the expression of CRGs and FRGs, patients were classified into cuproptosis and ferroptosis subtypes. Then, we constructed a risk model using least absolute shrinkage and selection operator (LASSO) analysis and Cox regression analysis based on ferroptosis and cuproptosis-related differentially expressed genes (DEGs). Patients were separated into two groups according to median risk score. We compared the immunophenotype, tumor microenvironment (TME), cancer stem cell index, and treatment sensitivity of two groups.

Three subtypes of ferroptosis and two subtypes of cuproptosis were identified among the patients. A greater likelihood of survival (P<0.05) was expected for patients in FRGcluster B and CRGcluster B. After that, a confirmed risk signature for ferroptosis and cuproptosis was developed and tested. Patients in the low-risk group had significantly higher survival rates than those in the high-risk group, according to our study (P<0.001). There was also a strong correlation between the signature and other variables including immunophenoscore, TMB, cancer stem cell index, immunological checkpoint genes, and sensitivity to chemotherapeutics.

Through this comprehensive research, we identified a unique risk signature associated with HCC patients' treatment status and prognosis. Our findings highlight FRGs' and CRGs' significance in clinical practice and imply ferroptosis and cuproptosis may be therapeutic targets for HCC patients.

Cuproptosis involves a direct interaction with the tricarboxylic acid (TCA) lipid acylation components. This process intricately intersects with post-transcriptional lipid acylation (LA) and is linked to mitochondrial respiration and LA metabolism. Copper ions form direct bonds with acylated DLAT, promoting DLAT oligomerization, reducing Fe-S cluster proteins, and inducing a protein-triggered toxic stress response that culminates in cell demise. Simultaneously, the importance of immune contexture in cancer progression and treatment has significantly increased. We assessed the expression of cuproptosis-related genes (CRGs) across TCGA and validated our findings using the GEO data. Consensus clustering divided esophageal cancer (ESCA) patients into two clusters based on the expression of 7 CRGs. We evaluated the expression of immune checkpoint inhibitor (ICI) targets and calculated the elevated tumor mutational burden (TMB). Weighted gene co-expression network analysis (WGCNA) identified genes associated with the expression of CRGs and immunity. Cluster 1 exhibited increased immune infiltration, higher expression of ICI targets, higher TMB, and a higher incidence of deficiency in mismatch repair-microsatellite instability-high status. WGCNA analysis identified 14 genes associated with the expression of CRGs and immune scores. ROC analysis revealed specific hub genes with strong predictive capabilities. The expression levels of SLC6A3, MITD1, and PDHA1 varied across different pathological stages; CCS, LIPT2, PDHB, and PDHA1 showed variation in response to radiation therapy; MITD1 and PDHA1 exhibited differences related to the pathological M stages of ESCA. CRGs influence the immune contexture and can potentially transform cold tumors into hot tumors in ESCA patients.

Dysregulated copper metabolism has been noticed in many types of cancer including hepatocellular carcinoma (HCC); however, a comprehensive understanding about this dysregulation still remains unclear in HCC.

A set of bioinformatic tools was integrated to analyze the expression and prognostic significance of copper metabolism-related genes. A related risk score, termed as CMscore, was developed via univariate Cox regression, least absolute shrinkage and selection operator (LASSO) Cox regression and multivariate Cox regression. Pathway enrichment analyses and tumor immune cell infiltration were further investigated in CMscore stratified HCC patients. Weighted correlation network analysis (WGCNA) was used to identify potential regulator of cuproptosis.

Copper metabolism was dysregulated in HCC. HCC patients in the high-CMscore group showed a significantly lower overall survival (OS) and enriched in most cancer-related pathways. Besides, HCC patients with high CMscore had higher expression of pro-tumor immune infiltrates and immune checkpoints. Moreover, cancer patients with high CMscore from two large cohorts exhibited significantly prolonged survival time after immunotherapy. WGCNA and subsequently correlation analysis revealed that SLC27A5 might be a potential regulator of cuproptosis in HCC. In vitro experiments revealed that SLC27A5 inhibited cell proliferation and migration of HCC cells and could upregulate FDX1, the key regulator of cuproptosis.

The CMscore is helpful in clustering HCC patients with distinct prognosis, gene mutation signatures, and sensitivity to immunotherapy. SLC27A5 might serve as a potential target in the induction of cuproptosis in HCC.

Cuproptosis is a new type of programmed cell death involved in the regulation of neuroendocrine tumors, immune microenvironment, and substance metabolism. However, the role of cuproptosis-related genes (CRGs) in Hepatocellular carcinoma (HCC) remains unclear.

Through multiple bioinformatics analysis, we constructed a prognostic gene model and competing endogenous RNA (ceRNA) network. The correlation between CRGs and prognosis, immune infiltration, immune checkpoints, microsatellite instability (MSI) and tumor mutational burden (TMB) was analyzed by Kaplan-Meier curve, univariate Cox, multivariate regression, and Spearman's analysis in HCC patients. Besides, the qRT-PCR and immunohistochemistry assays were used to determine prognostic CRGs mRNA and protein expression in HCC.

We established a novel 3-gene signature related to CRGs for evaluating the prognosis of HCC patients. HCC patients with high risk scores had a poor prognosis with an area under the curve of 0.737, 0.646, and 0.634 on 1-year, 3-year, and 5-year receiver operating characteristic curves. Significant correlation was observed between prognostic CRGs and immune infiltration, immune checkpoints, MSI and TMB. We also developed five ceRNA networks to regulate the occurrence and progression of HCC. CDKN2A, DLAT, and PDHA1 protein expression was up-regulated in HCC versus normal tissues. Besides, the mRNA expression levels of CDKN2A, DLAT, GLS, and PDHA1 were elevated in the HCC cell lines compared to the normal liver cell lines.

This novel prognostic CRGs signature could be accurately predict the prognosis of patients with HCC. The ceRNA regulatory network might be potential prognostic biomarkers and therapeutic targets for HCC patients.