Intracellular Copper Accumulation Research Articles

Curcumin suppresses copper accumulation in non-small cell lung cancer by binding ATOX1

BackgroundNon-small cell lung cancer (NSCLC) is associated with intracellular copper accumulation. Antioxidant 1 (ATOX1) is a copper chaperone. This study aimed to analyze the anti-cancer effects of curcumin on the ATOX1-mediated copper pathway in NSCLC.MethodsA binding activity between curcumin and ATOX1 was measured using molecular docking. NSCLC cells, A549 and H1299, were treated with different doses of curcumin (10, 20, 40 µM) or DC-AC50 (5, 10, 20 µM) for 24 h. The cell viability and levels of ATOX1, ATP7A and COX17 proteins were observed in cells. Overexpressing ATOX1 in cells was established by pcDNA3.1-ATOX1 transfection for 24 h. The ATOX1 overexpressing cells were treated with 40 µM curcumin or 20 µM DC-AC50 for 24 h to analyze the mechanism of curcumin in NSCLC treatment. Cell viability was measured by CCK-8, and levels of proteins were measured by western blotting. The copper level in cells was labeled by copper sensor-1. Moreover, nude mice models were induced by injection of A549 cells and treated with 20 mg/kg/d DC-AC50 or 40 mg/kg/d curcumin. Tumor growth was observed by measuring tumor volume and tumor weight. The levels of ATOX1, ATP7A and COX17 in tumors were measured by immunohistochemistry and western blotting.ResultsCurcumin bound to ATOX1 (score = −6.1 kcal/mol) and decreased the levels of ATOX1, ATP7A and COX17 proteins in NSCLC cells. The curcumin or DC-AC50 treatment suppressed cell viability by inhibiting the ATOX1-mediated copper signaling in NSCLC cells. The ATOX1 overexpression in cells significantly weakened the effects of curcumin on suppressing copper accumulation and the ATOX1-mediated copper pathway (p < 0.05). In mice models, curcumin or DC-AC50 treatment also suppressed tumor growth by suppressing the ATOX1-mediated copper pathway in tumors.ConclusionThis study demonstrated that curcumin bound ATOX1 to suppress copper accumulation in NSCLC cells, providing a new mechanism of curcumin for NSCLC treatment.

Copper mediated follicular atresia: Implications for granulosa cell death

3-nitropropanoic acid is a potent oxidative stress inducer that is conventionally regarded as a regulator of follicular atresia by regulating granulosa cells (GCs) death through the apoptosis pathway. There has been no research investigating the impact of copper metal overload induced Cuproptosis in ovarian GCs as a factor contributing to hindered follicular development.To elucidate whether 3-NP-induced oxidative stress plays a contributory role in promoting Cuproptosis, and discuss the role of Cuproptosis in the development of ovarian follicles.We conducted an analysis of cuproptosis occurrence in murine GCs and C57BL/6 J mice under the influence of 3-NP and 3-NP with added exogenous copper.The results revealed that 3-NP serving as a robust facilitator of exogenous copper uptake by upregulating the expression of copper transporter 1 (CTR1). In turn, culminated in the accumulation of intracellular copper within mouse granulosa cells (mGCs). Furthermore, 3-NP promoted mitochondrial permeability transition pore opening and concurrently reduced the stability of lipoic acid proteins. These actions collectively induced the oligomerization of Dihydrolipoamide S-Acetyltransferase (DLAT), ultimately leading to cuproptosis in GCs and consequent follicular atresia. Heavy metal copper and fungal decomposition product 3-NP, induce ovarian atresia via cuproptosis, modulating the reproductive performance of female animals.

A Water-Soluble Multifunctional Probe for Colorimetric Copper Sensing, Lysosome Labelling and Live-Cell Imaging.

We report a water-soluble fluorescence and colorimetric copper probe (LysoBC1); this system can also serve for lysosome labeling and for the dynamic tracking of Cu2+ in living cells. The sensing mechanism takes advantage of the synergic action by the following three components: i) a lysosome targeting unit, ii) the spirolactam ring-opening for the selective copper chelation and iii) the metal-mediated hydrolysis of the rhodamine moiety for fluorescence enhancement. In aqueous environment the molecule acts as a fluorescent reversible pH sensor and as colorimetric probe for Cu2+ at physiological pH; the hydrolysis of the copper targeting unit resulted in a 50-fold increase of the fluorescence intensity. Most importantly, in vitro cell analyses in undifferentiated (SH SY5Y) and differentiated (d-SH SY5Y) neuroblastoma cells, LysoBC1 is able to selectively accumulate into lysosome while the copper binding ability allowed us to monitor intracellular copper accumulation into lysosome.

Glutathione-Scavenging Celastrol-Cu Nanoparticles Induce Self-Amplified Cuproptosis for Augmented Cancer Immunotherapy.

Cuproptosis is a novel copper-dependent programmed cell death. The efficacy of cuproptosis is highly dependent on intracellular copper accumulation and counteracted by a high level of glutathione (GSH) in tumor cells. Here, this work develops a self-amplified cuproptosis nanoparticles (Cel-Cu NP) using celastrol (Cel), a natural product isolated from medical plant. In Cel-Cu NP, Cel serves as a versatile copper ionophore, exhibiting an ideal coordination capacity toward copper ions without compromising the cuproptosis induction. Notably, Cel can simultaneously scavenge GSH content to amplify cuproptosis. Moreover, this self-amplified cuproptosis further activates immunogenic cell death (ICD) to elicit robust immune response. Combining with immune checkpoint blockade, Cel-Cu NP effectively eradicates metastatic tumors in a mouse lung metastasis model. This study provides an efficient nanomedicine by inducing self-amplified cuproptosis for robust immunotherapy.

Sleep fragmentation exacerbates myocardial ischemia‒reperfusion injury by promoting copper overload in cardiomyocytes

Sleep disorders increase the risk and mortality of heart disease, but the brain-heart interaction has not yet been fully elucidated. Cuproptosis is a copper-dependent type of cell death activated by the excessive accumulation of intracellular copper. Here, we showed that 16 weeks of sleep fragmentation (SF) resulted in elevated copper levels in the male mouse heart and exacerbated myocardial ischemia–reperfusion injury with increased myocardial cuproptosis and apoptosis. Mechanistically, we found that SF promotes sympathetic overactivity, increases the germination of myocardial sympathetic nerve terminals, and increases the level of norepinephrine in cardiac tissue, thereby inhibits VPS35 expression and leads to impaired ATP7A related copper transport and copper overload in cardiomyocytes. Copper overload further leads to exacerbated cuproptosis and apoptosis, and these effects can be rescued by excision of the sympathetic nerve or administration of copper chelating agent. Our study elucidates one of the molecular mechanisms by which sleep disorders aggravate myocardial injury and suggests possible targets for intervention.

Abstract 1819: Esculetin modulates SLC31A1 and ATP7B to influence copper homeostasis and trigger cell death in colorectal cancer

Abstract Background: Esculetin is a naturally occurring dihydroxycoumarin with anti-inflammatory, antioxidant, and anti-tumor activities. Copper ion transport proteins, notably SLC31A1 and ATP7B, are essential in maintaining intracellular copper homeostasis, averting disruptions that might lead to copper-induced cell death under normal physiological conditions. However, prior research has not explored Esculetin's role in inducing copper-induced cell death. Hence, this study aims to investigate the biological process of Esculetin-induced cell death and the molecular mechanism underlying dysregulation of intracellular copper ion homeostasis. Methods: Initially, the CCK-8 assay was used to determine the IC50 values of Esculetin on colorectal cancer cell lines (HCT116, HT29, SW480) and normal colonic epithelial cell lines (NCM460). In terms of biological behaviors, the effects of Esculetin on the proliferation of colorectal cancer cell lines were assessed using CCK-8, colony formation assay, and EdU staining. Flow cytometry was used to examine the impact of Esculetin on apoptosis and cell cycle distribution in colorectal cancer cells. A subcutaneous xenograft tumor model in nude mice was employed to evaluate the in vivo anti-tumor effects of Esculetin, while IHC staining was conducted to detect Ki-67 levels, and Western blotting was performed to assess EMT-related protein expression. To investigate copper ion homeostasis, qPCR was used to measure the expression levels of copper ion transporters SLC31A1 and ATP7B before and after Esculetin treatment. Results: The CCK-8 results revealed that the IC50 of Esculetin for normal colonic epithelial cell lines was significantly higher than that for colorectal cancer cell lines. Meanwhile, a notable inhibitory effect of Esculetin on the proliferation of colorectal cancer cells was observed. Additionally, Esculetin treatment suppressed colony formation and reduced the proportion of EdU-positive cells in colorectal cancer cells. Flow cytometry demonstrated an increase in apoptosis and S-phase arrest following Esculetin treatment. The subcutaneous xenograft tumor model showed significant inhibition of tumor growth by Esculetin, as evidenced by reduced Ki-67-positive cells in the Esculetin-treated group. Western blot analysis revealed a significant decrease in the expression levels of Vimentin and N-Cadherin and an increase in E-Cadherin expression. Furthermore, qPCR analysis post-Esculetin treatment showed an elevation in the inward copper transporter SLC31A1 levels, while the outward transporter ATP7B expression decreased. Conclusion: Esculetin induces dysregulation of intracellular copper ion homeostasis by upregulating SLC31A1 expression and downregulating ATP7B expression, leading to intracellular copper accumulation and subsequent disruption of copper homeostasis, thereby inducing copper-induced cell death. Citation Format: Fangyue Guo, Mengying Liu, Kaihe Zhu, Jiapeng Ru, Pei Li, Shanfeng Zhang. Esculetin modulates SLC31A1 and ATP7B to influence copper homeostasis and trigger cell death in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1819.

Copper Deposition in Polydopamine Nanostructure to Promote Cuproptosis by Catalytically Inhibiting Copper Exporters of Tumor Cells for Cancer Immunotherapy.

Cuproptosis is an emerging programmed cell death, displaying great potential in cancer treatment. However, intracellular copper content to induce cuproptosis is unmet, which mainly ascribes to the intracellular pumping out equilibrium mechanism by copper exporter ATP7A and ATP7B. Therefore, it is necessary to break such export balance mechanisms for desired cuproptosis. Mediated by diethyldithiocarbamate (DTC) coordination, herein a strategy to efficiently assemble copper ions into polydopamine nanostructure (PDA-DTC/Cu) for reprogramming copper metabolism of tumor is developed. The deposited Cu2+ can effectively trigger the aggregation of lipoylated proteins to induce cuproptosis of tumor cells. Beyond elevating intracellular copper accumulation, PDA-DTC/Cu enables to break the balance of copper metabolism by disrupting mitochondrial function and restricting the adenosine triphosphate (ATP) energy supply, thus catalytically inhibiting the expressions of ATP7A and ATP7B of tumor cells to enhance cuproptosis. Meanwhile, the killed tumor cells can induce immunogenic cell death (ICD) to stimulate the immune response. Besides, PDA-DTC/Cu NPs can promote the repolarization of tumor-associated macrophages (TAMs ) to relieve the tumor immunosuppressive microenvironment (TIME). Collectively, PDA-DTC/Cu presented a promising "one stone two birds" strategy to realize copper accumulation and inhibit copper export simultaneously to enhance cuproptosis for 4T1 murine breast cancer immunotherapy.

A co-opted endogenous retroviral envelope promotes cell survival by controlling CTR1-mediated copper transport and homeostasis

Copper is a critical element for eukaryotic life involved in numerous cellular functions, including redox balance, but is toxic in excess. Therefore, tight regulation of copper acquisition and homeostasis is essential for cell physiology and survival. Here, we identify a different regulatory mechanism for cellular copper homeostasis that requires the presence of an endogenous retroviral envelope glycoprotein called Refrex1. We show that cells respond to elevated extracellular copper by increasing the expression of Refrex1, which regulates copper acquisition through interaction with the main copper transporter CTR1. Downmodulation of Refrex1 results in intracellular copper accumulation leading to reactive oxygen species (ROS) production and subsequent apoptosis, which is prevented by copper chelator treatment. Our results show that Refrex1 has been co-opted for its ability to regulate copper entry through CTR1 in order to limit copper excess, redox imbalance, and ensuing cell death, strongly suggesting that other endogenous retroviruses may have similar metabolic functions among vertebrates.

FDX1 inhibits thyroid cancer malignant progression by inducing cuprotosis

Cuprotosis is a recently identified cell death form that caused by intracellular copper accumulation and regulated by FDX1. This work aimed to explore the role of cuprotosis and the pivotal regulatory gene FDX1 in thyroid cancer development. We observed that expression of FDX1 in tumor section was notably lower than that in non-tumor sections in clinical samples. Induction of cuprotosis by elesclomol (ES) significantly repressed the in vitro and in vivo growth of thyroid cancer cells, simultaneously elevated Cu level and expression of FDX1, whereas depletion of FDX1 abolished these effects. Knockdown of FDX1 decreased the lipoylation level of DLAT and DLST in thyroid cancer cells, alleviated cuprotosis-induced cell death, simultaneously upregulated the levels of PA and α-KG. These findings demonstrated that FDX1 promotes the cuprotosis of thyroid cancer cells via regulating the lipoylation of DLAT.

Prediction of risk and clinical outcome of cuproptosis in lung squamous carcinoma

BackgroundLung squamous cell carcinoma (LUSC) is an important subtype of non-small cell lung cancer. Its special clinicopathological features and molecular background determine the limitations of its treatment. A recent study published on Science defined a newly regulatory cell death (RCD) form – cuproptosis. Which manifested as an excessive intracellular copper accumulation, mitochondrial respiration-dependent, protein acylation-mediated cell death. Different from apoptosis, pyroptosis, necroptosis, ferroptosis and other forms of regulatory cell death (RCD). The imbalance of copper homeostasis in vivo will trigger cytotoxicity and further affect the occurrence and progression of tumors. Our study is the first to predict the prognosis and immune landscape of cuproptosis-related genes (CRGs) in LUSC.MethodsThe RNA-seq profiles and clinical data of LUSC patients were downloaded from TCGA and GEO databases and then combined into a novel cohort. R language packages are used to analyze and process the data, and CRGs related to the prognosis of LUSC were screened according to the differentially expressed genes (DEGs). After analyzed the tumor mutation burden (TMB), copy number variation (CNV) and CRGs interaction network. Based on CRGs and DEGs, cluster analysis was used to classify LUSC patients twice. The selected key genes were used to construct a CRGs prognostic model to further analyze the correlation between LUSC immune cell infiltration and immunity. Through the risk score and clinical factors, a more accurate nomogram was further constructed. Finally, the drug sensitivity of CRGs in LUSC was analyzed.ResultsPatients with LUSC were divided into different cuproptosis subtypes and gene clusters, showing different levels of immune infiltration. The risk score showed that the high-risk group had higher tumor microenvironment score, lower tumor mutation load frequency and worse prognosis than the low-risk group. In addition, the high-risk group was more sensitive to vinorelbine, cisplatin, paclitaxel, doxorubicin, etoposide and other drugs.ConclusionsThrough bioinformatics analysis, we successfully constructed a prognostic risk assessment model based on CRGs, which can not only accurately predict the prognosis of LUSC patients, but also evaluate the patient 's immune infiltration status and sensitivity to chemotherapy drugs. This model shows satisfactory predictive results and provides a reference for subsequent tumor immunotherapy.

Cuproptosis-Related Gene Signature Contributes to Prognostic Prediction and Immunosuppression in Multiple Myeloma.

Cuproptosis is a type of programmed cell death triggered by accumulation of intracellular copper which was considered closely related to tumor progression. The study of cuproptosis in multiple myeloma (MM) is however limited. To determine the prognostic significance of cuproptosis-related gene signature in MM, we interrogated gene expression and overall survival with other available clinical variables from public datasets. Four cuproptosis-related genes were included to establish a prognostic survival model by least absolute shrinkage and selection operator (LASSO) Cox regression analysis, which showed a good performance on prognosis prediction in both training and validation cohorts. Patients with higher cuproptosis-related risk score (CRRS) exhibited worse prognosis compared with lower risk score. Survival prediction capacity and clinical benefit were elevated after integrating CRRS to existing prognostic stratification system (International Staging System, ISS or Revised International Staging System, RISS) both on 3-year and 5-year survival. Based on CRRS groups, functional enrichment analysis and immune infiltration in bone marrow microenvironment revealed correlation between CRRS and immunosuppression. In conclusion, our study found that cuproptosis-related gene signature is an independent poor prognostic factor and functions negatively on immune microenvironment, which provides another perspective on prognosis assessment and immunotherapy strategy in MM.

Construction and Validation of a Novel Prognosis Model in Colon Cancer Based on Cuproptosis-Related Long Non-Coding RNAs

Colon cancer (CC) is one of the most common (6%) malignancies and leading cause of cancer-associated death (more than 0.5 million) worldwide, which demands reliable prognostic biomarkers. Cuproptosis is a novel modality of regulated cell death triggered by the accumulation of intracellular copper. LncRNAs have been reported as prognostic signatures in different types of tumors. However, the correlation between cuproptosis-related lncRNAs (CRLs) and CC remains unclear. Data of CC patients were downloaded from public databases. The prognosis-associated CRLs were identified by co-expression analysis and univariate Cox. Least absolute shrinkage and selection operator were utilized to construct the CRLs-based prognostic signature in silico for CC patients. CRLs level was validated in human CC cell lines and patient tissues. ROC curve and Kaplan-Meier curve results revealed that high CRLs-risk score was associated with poor prognosis in CC patients. Moreover, the nomogram revealed that this model possessed a steady prognostic prediction capability with C-index as 0.68. More importantly, CC patients with high CRLs-risk score were more sensitive to eight targeted therapy drugs. The prognostic prediction power of the CRLs-risk score was further confirmed by cell lines, tissues and two independent CC cohorts. This study constructed a novel ten-CRLs-based prognosis model for CC patients. The CRLs-risk score is expected to serve as a promising prognostic biomarker and predict targeted therapy response in CC patients.

Construction and comprehensive analysis of a curoptosis-related lncRNA signature for predicting prognosis and immune response in cervical cancer.

Cuproptosis (copper-ion-dependent cell death) is an unprogrammed cell death, and intracellular copper accumulation, causing copper homeostasis imbalance and then leading to increased intracellular toxicity, which can affect the rate of cancer cell growth and proliferation. This study aimed to create a newly cuproptosis-related lncRNA signature that can be used to predict survival and immunotherapy in patients with cervical cancer, but also to predict prognosis in patients treated with radiotherapy and may play a role in predicting radiosensitivity. First of all, we found lncRNAs associated with cuproptosis between cervical cancer tumor tissues and normal tissues. By LASSO-Cox analysis, overlapping lncRNAs were then used to construct lncRNA signatures associated with cuproptosis, which can be used to predict the prognosis of patients, especially the prognosis of radiotherapy patients, ROC curves and PCA analysis based on cuprotosis-related lncRNA signature and clinical signatures were developed and demonstrated to have good predictive potential. In addition, differences in immune cell subset infiltration and differences in immune checkpoint expression between high-risk and low-risk score groups were analyzed, and we investigated the relationship between this signature and tumor mutation burden. In summary, we constructed a lncRNA prediction signature associated with cuproptosis. This has important clinical implications, including improving the predictive value of cervical cancer patients and providing a biomarker for cervical cancer.

ATF3/SPI1/SLC31A1 Signaling Promotes Cuproptosis Induced by Advanced Glycosylation End Products in Diabetic Myocardial Injury.

Cuproptosis resulting from copper (Cu) overload has not yet been investigated in diabetic cardiomyopathy (DCM). Advanced glycosylation end products (AGEs) induced by persistent hyperglycemia play an essential role in cardiotoxicity. To clarify whether cuproptosis was involved in AGEs-induced cardiotoxicity, we analyzed the toxicity of AGEs and copper in AC16 cardiomyocytes and in STZ-induced or db/db-diabetic mouse models. The results showed that copper ionophore elesclomol induced cuproptosis in cardiomyocytes. It was only rescued by copper chelator tetrathiomolybdate rather than by other cell death inhibitors. Intriguingly, AGEs triggered cardiomyocyte death and aggravated it when incubated with CuCl2 or elesclomol-CuCl2. Moreover, AGEs increased intracellular copper accumulation and exhibited features of cuproptosis, including loss of Fe-S cluster proteins (FDX1, LIAS, NDUFS8 and ACO2) and decreased lipoylation of DLAT and DLST. These effects were accompanied by decreased mitochondrial oxidative respiration, including downregulated mitochondrial respiratory chain complex, decreased ATP production and suppressed mitochondrial complex I and III activity. Additionally, AGEs promoted the upregulation of copper importer SLC31A1. We predicted that ATF3 and/or SPI1 might be transcriptional factors of SLC31A1 by online databases and validated that by ATF3/SPI1 overexpression. In diabetic mice, copper and AGEs increases in the blood and heart were observed and accompanied by cardiac dysfunction. The protein and mRNA profile changes in diabetic hearts were consistent with cuproptosis. Our findings showed, for the first time, that excessive AGEs and copper in diabetes upregulated ATF3/SPI1/SLC31A1 signaling, thereby disturbing copper homeostasis and promoting cuproptosis. Collectively, the novel mechanism might be an alternative potential therapeutic target for DCM.

Correlation between copper speciation and transport pathway in Caco-2 cells.

Previous studies have demonstrated that, in contrast to the properties of food-derived copper, water-derived copper exerts neurotoxic effects and exhibits different speciation during digestion. The cellular uptake efficiencies of different speciation of copper are distinct. However, it is unclear whether these different speciation share the same transport pathway in intestinal epithelial cells. In the present study, the intracellular accumulation of copper derived from copper ion and copper complex solutions was investigated in Caco-2 cells. The cellular accumulation of copper derived from copper ions was higher than that of copper derived from the copper complex. Treatment with carboplatin and Ag+ , which are copper transporter receptor 1 (Ctr1, LC31A1) inhibitors, did not inhibit copper accumulation in Caco-2 cells, but inhibited copper accumulation in HepG2 cells. Zinc ion significantly decreased the intracellular copper content from 114 ± 7μg g-1 protein to 88 ± 4μg g-1 protein in the copper ion-treated Caco-2 cells, but not in the copper complex-treated Caco-2 cells (84.6 ± 14 μg g-1 protein versus 87.7 ± 20 μg g-1 protein, P > 0.05). Additionally, copper accumulation in Caco-2 and HepG2 cells significantly differed depending on different solvents (Hanks' balanced salt solution and NaNO3 , P < 0.05). These results indicate that the intracellular accumulation of copper derived from copper ion and copper complex is mediated by distinct copper transport pathways. Copper speciation may be an important factor that affects copper absorption and toxicity. © 2022 Society of Chemical Industry.

System analysis based on the cuproptosis-related genes identifies LIPT1 as a novel therapy target for liver hepatocellular carcinoma

BackgroundLiver hepatocellular carcinoma (LIHC) ranks sixth among the most common types of cancer with a high mortality rate. Cuproptosis is a newly discovered type of cell death in tumor, which is characterized by accumulation of intracellular copper leading to the aggregation of mitochondrial lipoproteins and destabilization of proteins. Thus, understanding the exact effects of cuproptosis-related genes in LIHC and determining their prognosticvalue is critical. However, the prognostic model of LIHC based on cuproptosis-related genes has not been reported.MethodsFirstly, we downloaded transcriptome data and clinical information of LIHC patients from TCGA and GEO (GSE76427), respectively. We then extracted the expression of cuproptosis-related genes and established a prognostic model by lasso cox regression analysis. Afterwards, the prediction performance of the model was evaluated by Kaplan–Meier survival analysis and receiver operating characteristic curve (ROC). Then, the prognostic model and the expression levels of the three genes were validated using the dataset from GEO. Subsequently, we divided LIHC patients into two subtypes by non-negative matrix factorization (NMF) classification and performed survival analysis. We constructed a Sankey plot linking different subtypes and prognostic models. Next, we calculate the drug sensitivity of each sample from patients in the high-risk group and low-risk group by the R package pRRophetic. Finally, we verified the function of LIPT1 in LIHC.ResultsUsing lasso cox regression analysis, we developed a prognostic risk model based on three cuproptosis-related genes (GCSH, LIPT1 and CDKN2A). Both in the training and in the test sets, the overall survival (OS) of LIHC patients in the low-risk group was significantly longer than that in the high-risk group. By performing NMF cluster, we identified two molecular subtypes of LIHC (C1 and C2), with C1 subtype having significantly longer OS and PFS than C2 subtype. The ROC analysis indicated that our model had a precisely predictive capacity for patients with LIHC. The multivariate Cox regression analysis indicated that the risk score is an independent predictor. Subsequently, we identified 71 compounds with IC50 values that differed between the high-risk and low-risk groups. Finally, we determined that knockdown of LIPT1 gene expression inhibited proliferation and invasion of hepatoma cells.ConclusionIn this study, we developed a novel prognostic model for hepatocellular carcinoma based on cuproptosis-related genes that can effectively predict the prognosis of LIHC patients. The model may be helpful for clinicians to make clinical decisions for patients with LIHC and provide valuable insights for individualized treatment. Two distinct subtypes of LIHC were identified based on cuproptosis-related genes, with different prognosis and immune characteristics. In addition, we verified that LIPT1 may promote proliferation, invasion and migration of LIHC cells. LIPT1 might be a new potential target for therapy of LIHC.

Restoration of the Immunogenicity of Tumor Cells for Enhanced Cancer Therapy via Nanoparticle-Mediated Copper Chaperone Inhibition.

Recent progress in studying copper-dependent targets and pathways in the context of tumor treatment has provided new insights into therapeutic strategies of leveraging copper-dependent disease vulnerabilities and pharmacological manipulation of intratumor copper transportation to improve chemotherapy. Here, we developed reactive oxygen species (ROS)-sensitive nanoparticles loaded with copper chaperone inhibitor DC_AC50 and cisplatin(IV) prodrug. The released DC_AC50 can promote a remarkable accumulation of intracellular cisplatin and copper through inhibition of the Atox1-ATPase pathways, thereby enhancing the chemotherapeutic effect of cisplatin and inducing significant ROS generation. Excessive ROS then elicits intense endoplasmic reticulin (ER) stress which facilitates the immunogenic cell death (ICD) spurring a sustained immune response. Our study suggests that nanoparticle-mediated copper chaperone inhibition via DC_AC50 can restore the immunogenicity of tumor cells for enhanced chemotherapy and cancer immunotherapy.

Restoration of the Immunogenicity of Tumor Cells for Enhanced Cancer Therapy via Nanoparticle‐Mediated Copper Chaperone Inhibition

AbstractRecent progress in studying copper‐dependent targets and pathways in the context of tumor treatment has provided new insights into therapeutic strategies of leveraging copper‐dependent disease vulnerabilities and pharmacological manipulation of intratumor copper transportation to improve chemotherapy. Here, we developed reactive oxygen species (ROS)‐sensitive nanoparticles loaded with copper chaperone inhibitor DC_AC50 and cisplatin(IV) prodrug. The released DC_AC50 can promote a remarkable accumulation of intracellular cisplatin and copper through inhibition of the Atox1‐ATPase pathways, thereby enhancing the chemotherapeutic effect of cisplatin and inducing significant ROS generation. Excessive ROS then elicits intense endoplasmic reticulin (ER) stress which facilitates the immunogenic cell death (ICD) spurring a sustained immune response. Our study suggests that nanoparticle‐mediated copper chaperone inhibition via DC_AC50 can restore the immunogenicity of tumor cells for enhanced chemotherapy and cancer immunotherapy.

Enhancement of Intracellular Accumulation of Copper by Biogenesis of Lipid Droplets in Saccharomyces cerevisiae Revealed by Transcriptomic Analysis.

Copper is an essential micronutrient for life, whose homeostasis is rigorously regulated to meet the demands of normal biological processes and to minimize the potential toxicity. Copper enriched by yeast is regarded as a safe and bioavailable form of copper supplements. Here, a Saccharomyces cerevisiae mutant strain H247 with expanded storage capability of copper was obtained through atmospheric and room-temperature plasma treatment. Transcriptomic analyses found that transcriptional upregulation of DGA1 might be the major contributor to the enhancement of intracellular copper accumulation in strain H247. The positive correlation between biogenesis of lipid droplets and intracellular accumulation of copper was confirmed by overexpression of the diacylglycerol acyltransferase encoding genes DGA1 and LRO1 or knockout of DGA1. Lipid droplets are not only the storage pool of copper but might prompt the copper trafficking to mitochondria, vacuoles, and Golgi apparatus. These results provide new insights into the sophisticated copper homeostatic mechanisms and the biological functions of lipid droplets.

Enhancement of Copper Uptake of Yeast Through Systematic Optimization of Medium and the Cultivation Process of Saccharomyces cerevisiae.

Copper is an essential trace element for living organisms. Copper enriched by yeast of Saccharomyces cerevisiae is regarded as the biologically available organic copper supplement with great potentiality for application. However, the lower uptake ratio of copper ions makes the production of copper enriched by yeast uneconomically and environmentally unfriendly. In this study, S. cerevisiae Cu-5 with higher copper tolerance and intracellular copper accumulation was obtained by screening of our yeast strains collection. To increase the uptake ratio of copper ions, the medium composition and cultivation conditions for strain Cu-5 were optimized systematically. A medium comprised of glucose, yeast extract, (NH4)2SO4, and inorganic salts was determined, then a novel cultivation strategy including pH control at 5.5 and increasing amounts of yeast extract for a higher concentration of copper ion in the medium was developed. The uptake ratios of copper ions were more than 90% after combining 50 to 100mg/L copper ions with 3.5 to 5.0g/L yeast extract, which is the highest until now and is conducive to the cost-effective and environmentally friendly production of bioactive copper in yeast-enriched form.