Induction of Oxidative Stress Through Inhibition of Thioredoxin Reductase 1 Is an Effective Therapeutic Approach for Hepatocellular Carcinoma

Investigation of the effects of monosodium glutamate and tannic acid on the glutathione and thioredoxin systems in the liver of rats

While there is no conclusive evidence that monosodium glutamate (MSG, a food additive) directly causes liver cancer in humans, certain studies suggest a potential link between MSG-induced liver injury and cancer development. This study aimed to evaluate the protective effect of tannic acid (TA, a natural polyphenol) against MSG-induced hepatotoxicity through the glutathione and thioredoxin systems. Twenty-four rats were randomly divided into control and experimental groups and treated with TA, MSG, and MSG+TA once daily by oral gavage for 21 days. In addition to major oxidative stress indicators (total glutathione; GSH + GSSG and malondialdehyde; MDA), mRNA expression changes and biological activity responses of components of the glutathione and thioredoxin systems were examined in the liver tissues of all animals. The results showed that MSG alone negatively affected both stress indicators and antioxidant system components (glutathione peroxidase; GPx, glutathione reductase; GR, glutathione-S-transferase; GST, and thioredoxin reductase; TrxR) in terms of mRNA expression and biological activity. However, the combination of MSG and TA demonstrated robust antioxidative effects, surpassing the outcomes of MSG treatment. Our results provide new insights into pivotal molecular targets and protective candidates that should be focused on in future in vivo and in vitro HCC research.

Auranofin resensitizes ferroptosis-resistant lung cancer cells to ferroptosis inducers

Lung cancer, a major cause of cancer-related mortality, has limited therapeutic options, especially for advanced cases. Ferroptosis, an iron-dependent form of cell death, is a potential therapeutic strategy for this disease; however, resistance mechanisms in the tumor microenvironment impede its effectiveness. Therefore, in this study, we aimed to investigate the efficacy of sulfasalazine (SAS), a ferroptosis inducer, and auranofin (AUR), a Food and Drug Administration-approved anti-inflammatory agent, combination to counteract ferroptosis resistance in lung cancer. SAS induced ferroptosis in vitro; however, its efficacy in vivo was limited, possibly because of factors, such as nutrient deprivation and high cell density, in the microenvironment that suppressed the activities of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), key regulators of ferroptosis resistance. Screening of 2483 drugs revealed AUR as a compound resensitizing the YAP/TAZ-deficient lung cancer cells to ferroptosis. Moreover, SAS and AUR combination significantly enhanced lipid peroxidation and reactive oxygen species accumulation, further driving ferroptosis in cells. This combination effectively inhibited tumor growth and enhanced survival in a murine lung cancer model. Overall, our findings suggest that AUR potentiates ferroptosis-based therapies, serving as an effective candidate to overcome ferroptosis resistance in lung cancer.

Reactive Oxygen Species: From Tumorigenesis to Therapeutic Strategies in Cancer

BACKGROUND

Reactive oxygen species (ROS), a class of highly reactive molecules, are closely linked to the pathogenesis of various cancers. While ROS primarily originate from normal cellular processes, external stimuli can also contribute to their production. Cancer cells typically exhibit elevated ROS levels due to disrupted redox homeostasis, characterized by an imbalance between antioxidant and oxidant species. ROS play a dual role in cancer biology: at moderate levels, they facilitate tumor progression by regulating oncogenes and tumor suppressor genes, inducing mutations, promoting proliferation, extracellular matrix remodeling, invasion, immune modulation, and angiogenesis. However, excessive ROS levels can cause cellular damage and initiate apoptosis, necroptosis, or ferroptosis.

METHODS

This review explores molecular targets involved in redox homeostasis dysregulation and examines the impact of ROS on the tumor microenvironment (TME). Literature from recent in vitro and in vivo studies was analyzed to assess how ROS modulation contributes to cancer development and therapy.

RESULTS

Findings indicate that ROS influence cancer progression through various pathways and cellular mechanisms. Targeting ROS synthesis or enhancing ROS accumulation in tumor cells has shown promising anticancer effects. These therapeutic strategies exhibit significant potential to impair tumor growth while also interacting with elements of the TME.

CONCLUSION

The ROS serve as both promoters and suppressors of cancer depending on their intracellular concentration. Their complex role offers valuable opportunities for targeted cancer therapies. While challenges remain in precisely modulating ROS for therapeutic benefit, they hold promise as synergistic agents alongside conventional treatments, opening new avenues in cancer management.

Synthesis and discovery of simplified pleurotin analogs bearing tricyclic core as novel thioredoxin reductase inhibitors

Pleurotin (1) is a benzoquinone meroterpenoid known for its wide-spectrum antitumor and antibiotic activities, notably acting as natural inhibitors of the thioredoxin reductase (TrxR). Pleurotin (1) has been chemically synthesized, but only in milligram quantities through at least 13 longest linear steps with 0.8 % overall yield due to its complex structure such as fused hexacyclic core with 8 contiguous stereocenters. Therefore, structural simplification strategy is applied to pleurotin natural products for their structure-activity relationship (SAR) study and further therapeutics development. Herein, we judiciously designed pleurotin analogs of tricyclic A/D/E ring core, retaining the putative pharmacophore of para-quinone moiety D and its supportive A and E rings. Thus 16 simplified analogs of pleurotin bearing tricyclic A/D/E core were readily synthesized in only 2 to 6 steps with up to 50 % overall yield from commercially available materials. Significantly, the best analog 14f with benzonitrile substituent exhibited more potent TrxR inhibitory activity with an IC50 of 3.5 μM than the positive control micheliolide (IC50 = 6.23 μM). Furthermore, the mechanism study revealed that compound 14f could induce apoptosis of tumor cells by inducing ROS generation and inhibiting TrxR activities. Our study for the first time showed that the tricyclic A/D/E ring scaffold from the natural product pleurotin (1) with proper substitution can maintain or even improve the TrxR inhibitory and antiproliferative activities, with high synthetic accessibility, affording natural product-derived lead compounds for the further development of TrxR inhibitors as anti-tumor therapeutics.

A new opportunity for N-acetylcysteine. An outline of its classic antioxidant effects and its pharmacological potential as an epigenetic modulator in liver diseases treatment

Liver diseases represent a worldwide health problem accountable for two million deaths per year. Oxidative stress is critical for the development of these diseases. N-acetyl cysteine (NAC) is effective in preventing liver damage, both in experimental and clinical studies, and evidence has shown that the pharmacodynamic mechanisms of NAC are related to its antioxidant nature and ability to modulate key signaling pathways. Here, we provide a comprehensive description of the beneficial effects of NAC in the treatment of liver diseases, addressing the first evidence of its role as a scavenger and precursor of reduced glutathione, along with studies showing its immunomodulatory action, as well as the ability of NAC to modulate epigenetic hallmarks. We searched the PubMed database using the following keywords: oxidative stress, liver disease, epigenetics, antioxidants, NAC, and antioxidant therapies. There was no time limit to gather all available information on the subject. NAC has shown efficacy in treating liver damage, exerting mechanisms of action different from those of free radical scavengers. Like different antioxidant therapies, its effectiveness and safety are related to the administered dose; therefore, designing new pharmacological formulations for this drug is imperative to achieve an adequate response. Finally, there is still much to explore regarding its effect on epigenetic marker characteristics of liver damage, turning it into a drug with broad therapeutic potential. According to the literature reviewed, NAC could be an appropriate option in clinical studies related to hepatic injury and, in the future, a repurposing alternative for treating liver diseases.

Nuclear ANLN regulates transcription initiation related Pol II clustering and target gene expression

Anillin (ANLN), a mitotic protein that regulates contractile ring assembly, has been reported as an oncoprotein. However, the function of ANLN in cancer cells, especially in the nucleus, has not been fully understood. Here, we report a role of nuclear ANLN in gene transcriptional regulation. We find that nuclear ANLN directly interacts with the RNA polymerase II (Pol II) large subunit to form transcriptional condensates. ANLN enhances initiated Pol II clustering and promotes Pol II CTD phase separation. Short-term depletion of ANLN alters the chromatin binding and enhancer-mediated transcriptional activity of Pol II. The target genes of ANLN-Pol II axis are involved in oxidoreductase activity, Wnt signaling and cell differentiation. THZ1, a super-enhancer inhibitor, specifically inhibits ANLN-Pol II clustering, target gene expression and esophageal squamous cell carcinoma (ESCC) cell proliferation. Our results reveal the function of nuclear ANLN in transcriptional regulation, providing a theoretical basis for ESCC treatment.

Pifithrin-μ sensitizes mTOR-activated liver cancer to sorafenib treatment

TSC2, a suppressor of mTOR, is inactivated in up to 20% of HBV-associated liver cancer. This subtype of liver cancer is associated with aggressive behavior and early recurrence after hepatectomy. Being the first targeted regimen for advanced liver cancer, sorafenib has limited efficacy in HBV-positive patients. In this study, we observed that mTOR-activated cells, due to the loss of either TSC2 or PTEN, were insensitive to the treatment of sorafenib. Mechanistically, HSP70 enhanced the interaction between active mTOR-potentiated CREB1 and CREBBP to boost the transcription of the antioxidant response regulator SESN3. In return, elevated SESN3 enhanced cellular antioxidant capacity and rendered cells resistant to sorafenib. Pifithrin-μ, an HSP70 inhibitor, synergized with sorafenib in the induction of ferroptosis in mTOR-activated liver cancer cells and suppression of TSC2-deficient hepatocarcinogenesis. Our findings highlight the pivotal role of the mTOR-CREB1-SESN3 axis in sorafenib resistance of liver cancer and pave the way for combining pifithrin-μ and sorafenib for the treatment of mTOR-activated liver cancer.

The Effects of Anthropogenic Stressors on Above- and Belowground Phytochemical Diversity of the Wetland Grass, Phragmites australis

Coastal wetlands face threats from climate change-induced flooding and biological invasions. Plants respond to these stressors through changes in their phytochemical metabolome, but it is unclear whether stressors affecting one tissue compartment (e.g., leaves) create vulnerabilities in others (e.g., roots) or elicit similar responses across tissues. Additionally, responses to multiple simultaneous stressors remain poorly understood due to the focus on individual metabolites in past studies. This study aims to elucidate how the phytochemical metabolome of three Phragmites australis (Cav.) lineages, common in the Mississippi River Delta, responds to flooding and infestation by the non-native scale insect Nipponaclerda biwakoensis (Kuwana). Among these lineages, one is non-native and poses a threat to North American wetlands. Results indicate that metabolomic responses are highly specific, varying with lineage, tissue type, stressor type, and the presence of multiple stressors. Notably, the non-native lineage displayed high chemical evenness, while the other two showed stressor-dependent responses. The 10 most informative features identified by a machine learning model showed less than 1% overlap with known metabolites linked to water and herbivory stress, underscoring gaps in our understanding of plant responses to environmental stressors. Our metabolomic approach offers a valuable tool for identifying candidate plant genotypes for wetland restoration.

Prognostic prediction signature and molecular subtype for liver cancer: A CTC/CTM‑related gene prediction model and independent external validation

Liver cancer is the second leading cause of tumor-related death worldwide, and a serious threat to lives and health. Circulating tumor cells (CTCs) facilitate the progression of various cancers, including liver cancer. The relationship between CTC/circulating tumor microemboli-related genes (CRGs) and the prognosis of liver cancer is unclear. The aim of the present study was to identify CTC/circulating tumour microemboli-related genes (CRGs) in hepatocellular carcinoma and to investigate their clinical significance. Transcriptomic data from The Cancer Genome Atlas (International Cancer Genome Consortium (ICGC) and GSE117623 databases were combined, and differentially expressed CRGs were identified. These were subsequently analyzed via least absolute shrinkage and selection operator and multivariate Cox analyses, and a five-gene risk signature was constructed. The signature was validated in the ICGC and GSE14520 dataset with survival analysis and receiver operating characteristic curve analysis. Immunocyte infiltration, tumor mutation burden (TMB), tumor immune dysfunction and exclusion (TIDE), and the somatic mutation rate were also compared between high- and low-risk groups, based on the median predictive index, to further evaluate the immunotherapeutic value of the model. Molecular subtypes of liver cancer were characterized by the non-negative matrix factorization method and potential therapeutic compounds were evaluated for different subtypes. Nomograms were utilized to predict the prognosis of patients, and the signature was compared with previous literature models. Additionally, the biological function of one of the CRGs, tumor protein p53 inducible protein 3 (TP53I3), in liver cancer was further explored through in vitro experiments. Analysis of the prognostic characteristics of the five CRGs led to the identification of two liver cancer subtypes. Patients in the low-risk group had a longer survival compared with those in the high-risk group, and patients in the latter group were associated with a higher TMB, immunocyte infiltration and somatic mutation rate, and lower TIDE scores. The prognostic profile was validated in the ICGC and GSE14520 datasets and exhibited a good predictive performance. In vitro analysis showed that the knockdown of TP53I3 suppressed liver cancer cell proliferation. In summary, CRGs were used to develop a new prognostic signature to predict the prognosis of patients with liver cancer. This signature may be used to assess the prognosis of patients and may provide new insights for clinical management strategies. In addition, TP53I3 is potentially a therapeutic target for liver cancer.

Pseudouridine synthase 1 promotes hepatocellular carcinoma through mRNA pseudouridylation to enhance the translation of oncogenic mRNAs

BACKGROUND AND AIMS

Pseudouridine is a prevalent RNA modification and is highly present in the serum and urine of patients with HCC. However, the role of pseudouridylation and its modifiers in HCC remains unknown. We investigated the function and underlying mechanism of pseudouridine synthase 1 (PUS1) in HCC.

APPROACH AND RESULTS

By analyzing the TCGA data set, PUS1 was found to be significantly upregulated in human HCC specimens and positively correlated with tumor grade and poor prognosis of HCC. Knockdown of PUS1 inhibited cell proliferation and the growth of tumors in a subcutaneous xenograft mouse model. Accordingly, increased cell proliferation and tumor growth were observed in PUS1-overexpressing cells. Furthermore, overexpression of PUS1 significantly accelerates tumor formation in a mouse HCC model established by hydrodynamic tail vein injection, while knockout of PUS1 decreases it. Additionally, PUS1 catalytic activity is required for HCC tumorigenesis. Mechanistically, we profiled the mRNA targets of PUS1 by utilizing surveying targets by apolipoprotein B mRNA-editing enzyme 1 (APOBEC1)-mediated profiling and found that PUS1 incorporated pseudouridine into mRNAs of a set of oncogenes, thereby endowing them with greater translation capacity.

CONCLUSIONS

Our study highlights the critical role of PUS1 and pseudouridylation in HCC development, and provides new insight that PUS1 enhances the protein levels of a set of oncogenes, including insulin receptor substrate 1 (IRS1) and c-MYC, by means of pseudouridylation-mediated mRNA translation.

GLO1 regulates hepatocellular carcinoma proliferation and migration through the cell cycle pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is a malignant tumor characterized by a high mortality rate. The occurrence and progression of HCC are linked to oxidative stress. Glyoxalase-1 (GLO1) plays an important role in regulating oxidative stress, yet the underlying mechanism remains unclear. GLO1 may serve as a prognostic biomarker and therapeutic target for HCC.

METHODS

Based on TCGA database hepatocellular carcinoma samples, we conducted a bioinformatics analysis to explore the correlation between GLO1 expression and HCC cell proliferation and viability. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that differentially expressed genes (DEGs) were mainly enriched in the cell cycle pathway. We analyzed the relationships between GLO1 and 24 genes enriched in the cell cycle pathway using a protein-protein interaction (PPI) network. Finally, experimental validation was performed to assess GLO1's impact on the distribution of cells at different cell cycle stages and on the proliferation and migration of HCC cells.

RESULTS

Our study demonstrated that GLO1 was overexpressed in HCC tissues and was associated with a poor prognosis. Data analysis indicated that overexpression of GLO1 activated the cell cycle pathway and positively correlated with expression of the majority of key cell cycle genes. Experimental validation showed that GLO1 expression affects the number of HCC cells in G2 and S phases and regulates HCC cell proliferation and migration.

CONCLUSIONS

GLO1 represents a promising therapeutic target for HCC, providing valuable insights into its role in the viability and proliferation of HCC cells.

The m5C/m6A/m7G-related non-apoptotic regulatory cell death genes for the prediction of the prognosis and immune infiltration status in hepatocellular carcinoma

Background

5-methylcytosine/N6-methyladenosine/N7-methylguanosine (m5C/m6A/m7G)-related genes play a critical role in tumor occurrence and progression, and non-apoptotic regulatory cell death (NARCD) is closely linked to tumor development and immunity. However, the role of m5C/m6A/m7G-related NARCD genes in hepatocellular carcinoma (HCC) remains unclear. We used m5C/m6A/m7G-related NARCD genes to construct a prognostic model of HCC for prognostic prediction and clinical treatment of patients.

Methods

We obtained transcriptome data for HCC from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Using the least absolute shrinkage and selection operator (LASSO) regression, we identified m5C/m6A/m7G-related NARCD genes and constructed a prognostic model through multivariate Cox regression. Model performance was assessed using Kaplan-Meier and receiver operating characteristic (ROC) curves, with external validation using the ICGC. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses were used to study differentially expressed genes between high- and low-risk groups. We also examined immune cell infiltration, drug response, and cell communication between tumor cells and immune cells in high-risk groups.

Results

We identified 140 m5C/m6A/m7G-related NARCD genes, using five of them to build the prognostic model. Functional enrichment analysis revealed enrichment in tumor and immune-related pathways for risk genes. The high-risk group displayed increased immune cell infiltration and better responses to immune checkpoint inhibitors (ICIs). High-risk patients were more responsive to cisplatin, doxorubicin, and mitomycin C, while low-risk patients were more sensitive to erlotinib. Cell communication analysis indicated that high-risk tumor cells used insulin-like growth factor (IGF) and macrophage migration inhibitory factor (MIF) signaling pathways to send signals to immune cells and received signals through the bone morphogenetic protein (BMP) and lymphotoxin-related inducible ligand (LIGHT) pathways.

Conclusions

We have developed a prognostic model with m5C/m6A/m7G-related NARCD genes to predict the prognosis of HCC patients. This model can offer insights into the effectiveness of immunotherapy and chemotherapy for HCC patients.

The "Doorstop Pocket" In Thioredoxin Reductases─An Unexpected Druggable Regulator of the Catalytic Machinery

Pyridine nucleotide-disulfide oxidoreductases are underexplored as drug targets, and thioredoxin reductases (TrxRs) stand out as compelling pharmacological targets. Selective TrxR inhibition is challenging primarily due to the reliance on covalent inhibition strategies. Recent studies identified a regulatory and druggable pocket in Schistosoma mansoni thioredoxin glutathione reductase (TGR), a TrxR-like enzyme, and an established drug target for schistosomiasis. This site is termed the "doorstop pocket" because compounds that bind there impede the movement of an aromatic side-chain necessary for the entry and exit of NADPH and NADP+ during enzymatic turnover. This discovery spearheaded the development of new TGR inhibitors with efficacies surpassing those of current schistosomiasis treatment. Targeting the "doorstop pocket" is a promising strategy, as the pocket is present in all members of the pyridine nucleotide-disulfide oxidoreductase family, opening new avenues for exploring therapeutic approaches in diseases where the importance of these enzymes is established, including cancer and inflammatory and infectious diseases.

Targeted Drug Delivery Strategies for the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks among the most prevalent malignant tumors, exhibiting a high incidence rate that presents a substantial threat to human health. The use of sorafenib and lenvatinib, commonly employed as single-agent targeted inhibitors, complicates the treatment process due to the absence of definitive targeting. Nevertheless, the advent of nanotechnology has injected new optimism into the domain of liver cancer therapy. Nanocarriers equipped with active targeting or passive targeting mechanisms have demonstrated the capability to deliver drugs to tumor cells with high efficiency. This approach not only facilitates precise delivery to the affected site but also enables targeted drug release, thereby enhancing therapeutic efficacy. As medical technology progresses, there is an increasing call for innovative treatment modalities, including novel chemotherapeutic agents, gene therapy, phototherapy, immunotherapy, and combinatorial treatments for HCC. These emerging therapies are anticipated to yield improved clinical outcomes for patients, while minimizing systemic toxicity and adverse effects. Consequently, the application of nanotechnology is poised to significantly improve HCC treatment. This review focused on targeted strategies for HCC and the application of nanotechnology in this area.

Sulfiredoxin-1 promotes the growth of hepatocellular carcinoma by inhibiting TFEB-mediated autophagy and lysosome biogenesis

Advanced hepatocellular carcinoma (HCC) patients have poor prognosis. As an endogenous antioxidant enzyme involved in a variety of bioprocesses, sulfiredoxin-1 (SRXN1) plays an irreplaceable role in promoting the development of tumors. However, the role and working mechanism of SRXN1 in HCC remain unclear. In this study, we confirmed that SRXN1 promoted the cell proliferation of HCC at genetic and pharmacological level, respectively. Transcriptome sequencing analysis revealed SRXN1 knockdown had a significant effect on the expression of lysosome biogenesis related genes. Further experiments validated that lysosome biogenesis and autophagic flux were enhanced after SRXN1 inhibition and reduced as SRXN1 overexpression. Mechanism study revealed that ROS accumulation induced TFEB nuclear translocation, followed by increased autophagy. Following this rationale, the combination of SRXN1 inhibitor and sorafenib demonstrated noticeable synergistic antitumor effect through the boost of ROS both in vivo and in vitro. Taken together, SRXN1 could be a potential therapeutic target for HCC therapy.

Unique features of KGN granulosa-like tumour cells in the regulation of steroidogenic and antioxidant genes

The ovarian KGN granulosa-like tumour cell line is commonly used as a model for human granulosa cells, especially since it produces steroid hormones. To explore this further, we identified genes that were differentially expressed by KGN cells compared to primary human granulosa cells using three public RNA sequence datasets. Of significance, we identified that the expression of the antioxidant gene TXNRD1 (thioredoxin reductase 1) was extremely high in KGN cells. This is ominous since cytochrome P450 enzymes leak electrons and produce reactive oxygen species during the biosynthesis of steroid hormones. Gene Ontology (GO) analysis identified steroid biosynthetic and cholesterol metabolic processes were more active in primary granulosa cells, whilst in KGN cells, DNA processing, chromosome segregation and kinetochore pathways were more prominent. Expression of cytochrome P450 cholesterol side-chain cleavage (CYP11A1) and cytochrome P450 aromatase (CYP19A1), which are important for the biosynthesis of the steroid hormones progesterone and oestrogen, plus their electron transport chain members (FDXR, FDX1, POR) were measured in cultured KGN cells. KGN cells were treated with 1 mM dibutyryl cAMP (dbcAMP) or 10 μM forskolin, with or without siRNA knockdown of TXNRD1. We also examined expression of antioxidant genes, H2O2 production by Amplex Red assay and DNA damage by γH2Ax staining. Significant increases in CYP11A1 and CYP19A1 were observed by either dbcAMP or forskolin treatments. However, no significant changes in H2O2 levels or DNA damage were found. Knockdown of expression of TXNRD1 by siRNA blocked the stimulation of expression of CYP11A1 and CYP19A1 by dbcAMP. Thus, with TXNRD1 playing such a pivotal role in steroidogenesis in the KGN cells and it being so highly overexpressed, we conclude that KGN cells might not be the most appropriate model of primary granulosa cells for studying the interplay between ovarian steroidogenesis, reactive oxygen species and antioxidants.

Oxidative cell death in cancer: mechanisms and therapeutic opportunities

Reactive oxygen species (ROS) are highly reactive oxygen-containing molecules generated as natural byproducts during cellular processes, including metabolism. Under normal conditions, ROS play crucial roles in diverse cellular functions, including cell signaling and immune responses. However, a disturbance in the balance between ROS production and cellular antioxidant defenses can lead to an excessive ROS buildup, causing oxidative stress. This stress damages essential cellular components, including lipids, proteins, and DNA, potentially culminating in oxidative cell death. This form of cell death can take various forms, such as ferroptosis, apoptosis, necroptosis, pyroptosis, paraptosis, parthanatos, and oxeiptosis, each displaying distinct genetic, biochemical, and signaling characteristics. The investigation of oxidative cell death holds promise for the development of pharmacological agents that are used to prevent tumorigenesis or treat established cancer. Specifically, targeting key antioxidant proteins, such as SLC7A11, GCLC, GPX4, TXN, and TXNRD, represents an emerging approach for inducing oxidative cell death in cancer cells. This review provides a comprehensive summary of recent progress, opportunities, and challenges in targeting oxidative cell death for cancer therapy.

Shikonin inhibits the growth of anaplastic thyroid carcinoma cells by promoting ferroptosis and inhibiting glycolysis

Anaplastic thyroid carcinoma is one of the highly fatal cancers and poses a serious threat to human health. Ferroptosis has been widely studied and proved to have an important role in tumor suppression, providing new avenues for cancer therapy; glutathione peroxidase 4(GPX4) and selenoprotein thioredoxin reductase(TXNRD1) are important regulatory targets in ferroptosis.Warburg effect is one of the important energy sources for cancer hypermetabolism, and pyruvate kinase isoenzyme 2 (PKM2) is a key metabolism enzyme that is important in this effect. Shikonin(SKN) is a Chinese herb that has been extensively studied for its anti-tumor ability. The aim of this study was to investigate the mechanism of anti-tumor effect of SKN in ATC cells and to elucidate the role played by ferroptosis and glycolysis in this inhibitory mechanism. The effects of SKN in ATC cell lines CAL-62 and 8505C cells were detected by flow cytometry, Western blotting,real-time quantitative PCR and a fluorescent probe for reactive oxygen species (ROS) to detect changes in intracellular ROS positivity; glucose and lactate assay kits to detect the levels of the raw material of glucose metabolism, glucose (GLU), and the product of glucose metabolism, lactate (LD); and the establishment of the BALB/C nude mice subcutaneous tumor model to analyse the inhibitory effect of SKN on ATC in vivo. The present study demonstrated that SKN inhibits the expression of NF-κB,GPX4,TXNRD1,PKM2,GLUT1.SKN inhibits ATC cell growth by down-regulating the occurrence of intracellular ferroptosis and inhibiting glycolysis in ATC cells.

Molecular Mechanisms of the Therapeutic Effect of Selenium Nanoparticles in Hepatocellular Carcinoma

This review describes and summarizes, for the first time, the molecular mechanisms of the cytotoxic effect of selenium nanoparticles of various origins on hepatocellular carcinoma cells. The text provides information from recent years indicating the regulation of various signaling pathways and endoplasmic reticulum stress by selenium nanoparticles; the pathways of cell death of liver cancer cells as a result of exposure to selenium nanoparticles are considered. Particular attention is paid to the participation of selenoproteins and selenium-containing thioredoxin reductases and glutathione peroxidases in these processes. Previously, there were no reviews that fully reflected the cytotoxic effects of selenium nanoparticles specifically in hepatocellular carcinoma, despite the fact that many reviews and experimental articles have been devoted to the causes of this disease and the molecular mechanisms of regulation of cytotoxic effects by other agents. The relevance of this review is primarily explained by the fact that despite the development of various drugs and approaches for the treatment and prevention of hepatocellular carcinoma, this disease is still the fourth leading cause of death in the world. For this reason, a complete understanding of the latest trends in the treatment of oncology of various etiologies, especially hepatocellular carcinoma, is extremely important.

Plasma concentrations of thioredoxin, thioredoxin reductase and peroxiredoxin-4 can identify high risk patients and predict outcome in patients with acute coronary syndrome: A clinical observation

BACKGROUND

Oxidative stress is a pathological feature of acute coronary syndrome (ACS), a complex disease with varying clinical outcomes. Surrogate biomarkers of oxidative stress including, peroxiredoxin-2 (PRDX2), PRDX4, thioredoxin (TRX) and thioredoxin reductase (TRXR) were measured in ACS patients at presentation and follow-up, to assess their clinical utility in diagnosis and risk stratification.

METHODS

Plasma from 145 participants (80 ACS and 65 healthy) at diagnosis, 1-3 month (first) and 6-month follow-up (second) was analysed by ELISA. ACS patients were monitored for 12-months.

RESULTS

ACS patients at diagnosis had significantly higher concentrations of TRX (p < 0.05), TRXR (p < 0.01) and PRDX4 (p < 0.01), compared to healthy donors. This was increase was driven by non-ST elevated myocardial infarction for TRX (p < 0.01) and PRDX4 (p < 0.05). For TRXR, ACS females were significantly higher than males (p < 0.05). TRX was also higher in older females (>55 years) at diagnosis (p < 0.05). At first follow-up, TRX had lowered, whereas PRDX4 remained significantly high (p < 0.05). Stratification of ACS patients according to percutaneous coronary intervention (PCI) revealed that TRXR was significantly higher in patients receiving PCI to the right coronary artery (p < 0.05). Whereas both TRXR (p < 0.01) and PRDX4 (p < 0.01) were significantly higher in patients receiving PCI to the left anterior descending (LAD) artery. ACS patients who had plasma TRX >13.40 ng/ml at second follow-up were at high risk of readmission (p < 0.05), as were patients with TRXR of <1000 pg/ml at diagnosis having PCI to the LAD (p < 0.05).

CONCLUSION

This study indicates that TRX, TRXR and PRDX4 may have clinical utility for ACS stratification.

Tumor cells express and maintain HMGB1 in the reduced isoform to enhance CXCR4-mediated migration

During inflammation and tissue regeneration, the alarmin High Mobility Group Box 1 (HMGB1), in its reduced isoform, enhances the activity of the chemokine CXCL12, forming a heterocomplex that acts via the chemokine receptor CXCR4. Despite the established roles of both HMGB1 and CXCL12 in tumor progression and metastatic spread to distal sites, the role of the CXCL12/HMGB1 heterocomplex in cancer has never been investigated. By employing a newly established mass spectrometry protocol that allows an unambiguous distinction between reduced (red-HMGB1) and oxidized (ox-HMGB1) HMGB1 isoforms in cell lysates, we demonstrate that human epithelial cells derived from breast (MCF-7 and MDA-MB-231) and prostate (PC-3) cancer predominantly express red-HMGB1, while primary CD3+ T lymphocytes from peripheral blood express both HMGB1 isoforms. All these cancer cells release HMGB1 in the extracellular microenvironment together with varying concentrations of thioredoxin and thioredoxin reductase. The CXCL12/HMGB1 heterocomplex enhances, via CXCR4, the directional migration and invasiveness of cancer cells characterized by high metastatic potential that possess a fully active thioredoxin system, contributing to maintain red-HMGB1. On the contrary, cancer cells with low metastatic potential, lack thioredoxin reductase, promptly uptake CXCL12 and fail to respond to the heterocomplex. Our study demonstrates that the responsiveness of cancer cells to the CXCL12/HMGB1 heterocomplex, resulting in enhanced cell migration and invasiveness, depends on the maintenance of HMGB1 in its reduced isoform, and suggests disruption of the heterocomplex as a potential therapeutic target to inhibit invasion and metastatic spread in cancer therapies.

Antenatal Ureaplasma Infection Causes Colonic Mucus Barrier Defects: Implications for Intestinal Pathologies

Chorioamnionitis is a risk factor for necrotizing enterocolitis (NEC). Ureaplasma parvum (UP) is clinically the most isolated microorganism in chorioamnionitis, but its pathogenicity remains debated. Chorioamnionitis is associated with ileal barrier changes, but colonic barrier alterations, including those of the mucus barrier, remain under-investigated, despite their importance in NEC pathophysiology. Therefore, in this study, the hypothesis that antenatal UP exposure disturbs colonic mucus barrier integrity, thereby potentially contributing to NEC pathogenesis, was investigated. In an established ovine chorioamnionitis model, lambs were intra-amniotically exposed to UP or saline for 7 d from 122 to 129 d gestational age. Thereafter, colonic mucus layer thickness and functional integrity, underlying mechanisms, including endoplasmic reticulum (ER) stress and redox status, and cellular morphology by transmission electron microscopy were studied. The clinical significance of the experimental findings was verified by examining colon samples from NEC patients and controls. UP-exposed lambs have a thicker but dysfunctional colonic mucus layer in which bacteria-sized beads reach the intestinal epithelium, indicating undesired bacterial contact with the epithelium. This is paralleled by disturbed goblet cell MUC2 folding, pro-apoptotic ER stress and signs of mitochondrial dysfunction in the colonic epithelium. Importantly, the colonic epithelium from human NEC patients showed comparable mitochondrial aberrations, indicating that NEC-associated intestinal barrier injury already occurs during chorioamnionitis. This study underlines the pathogenic potential of UP during pregnancy; it demonstrates that antenatal UP infection leads to severe colonic mucus barrier deficits, providing a mechanistic link between antenatal infections and postnatal NEC development.

BRMS1L confers anticancer activity in non-small cell lung cancer by transcriptionally inducing a redox imbalance in the GPX2-ROS pathway

Low expression levels of breast cancer metastasis suppressor 1 like (BRMS1L) have been associated with the growth of cancer cells. However, the mechanisms underlying the role of BRMS1L as an antitumour transcription factor in the progression of NSCLC have not been explored. Herein, we reveal that BRMS1L plays a key role as a tumour suppressor in inhibiting NSCLC proliferation and metastasis. Mechanistically, BRMS1L overexpression results in the downregulation of glutathione peroxidase 2 (GPX2) expression and consequently causes abnormal glutathione metabolism and increased levels of reactive oxygen species (ROS) in cells, inducing oxidative stress injury and apoptosis. Furthermore, overexpression of GPX2 enhances the growth advantage and oxidative stress repair conferred by knockdown of BRMS1L. Importantly, we show that low expression of BRMS1L in NSCLC cells causes relatively high levels of antioxidant accumulation to maintain cell redox balance and renders cancer cells more sensitive to treatment with piperlongumine as an ROS inducer both in vitro and in vivo. These findings offer new insights into the role of BRMS1L as a transcriptional repressor in NSCLC and suggest that the BRMS1L expression level may be a potential biomarker for predicting the therapeutic response to small molecule ROS inducers, providing new ideas for targeted therapy.

Current Trends on the Involvement of Zinc, Copper, and Selenium in the Process of Hepatocarcinogenesis

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.

Gold(I) ion and the phosphine ligand are necessary for the anti-Toxoplasma gondii activity of auranofin

Auranofin, an FDA-approved drug for rheumatoid arthritis, has emerged as a promising antiparasitic medication in recent years. The gold(I) ion in auranofin is postulated to be responsible for its antiparasitic activity. Notably, aurothiomalate and aurothioglucose also contain gold(I), and, like auranofin, they were previously used to treat rheumatoid arthritis. Whether they have antiparasitic activity remains to be elucidated. Herein, we demonstrated that auranofin and similar derivatives, but not aurothiomalate and aurothioglucose, inhibited the growth of Toxoplasma gondii in vitro. We found that auranofin affected the T. gondii biological cycle (lytic cycle) by inhibiting T. gondii's invasion and triggering its egress from the host cell. However, auranofin could not prevent parasite replication once T. gondii resided within the host. Auranofin treatment induced apoptosis in T. gondii parasites, as demonstrated by its reduced size and elevated phosphatidylserine externalization (PS). Notably, the gold from auranofin enters the cytoplasm of T. gondii, as demonstrated by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).IMPORTANCEToxoplasmosis, caused by Toxoplasma gondii, is a devastating disease affecting the brain and the eyes, frequently affecting immunocompromised individuals. Approximately 60 million people in the United States are already infected with T. gondii, representing a population at-risk of developing toxoplasmosis. Recent advances in treating cancer, autoimmune diseases, and organ transplants have contributed to this at-risk population's exponential growth. Paradoxically, treatments for toxoplasmosis have remained the same for more than 60 years, relying on medications well-known for their bone marrow toxicity and allergic reactions. Discovering new therapies is a priority, and repurposing FDA-approved drugs is an alternative approach to speed up drug discovery. Herein, we report the effect of auranofin, an FDA-approved drug, on the biological cycle of T. gondii and how both the phosphine ligand and the gold molecule determine the anti-parasitic activity of auranofin and other gold compounds. Our studies would contribute to the pipeline of candidate anti-T. gondii agents.

Evaluation of serum thioredoxin as a hepatocellular carcinoma diagnostic marker

Background

Hepatocellular carcinoma (HCC) is one of the most prevalent and fatal malignancies worldwide. Following an increase in reactive oxygen species (ROS), cancer cells enter an oxidative stress state. As a result, these cells experience an increase in antioxidant activity to counteract oxidative stress. The thioredoxin (TRX) system is a ubiquitous mammalian antioxidant system that neutralizes ROS and maintains intracellular reduction oxidation (redox) balance, which is essential for HCC growth. However, the role of TRX protein in HCC remains largely unknown. Hence, we aimed to assess the diagnostic utility of serum TRX in patients with HCC. A total of 50 patients were consecutively recruited in this observational study. They were classified into three groups: an HCC group (25 patients), a cirrhosis group (15 patients with liver cirrhosis on top of chronic HCV infection), and a control group (10 healthy individuals). Serum TRX levels were measured using ELISA.

Results

Higher serum TRX levels were detected in the HCC group than in the cirrhosis and control groups (140.96 ± 12.70 vs 88.33 ± 10.34 vs 73.10 ± 13.22 ng/mL, respectively; P < 0.001). TRX was independently associated with the presence of HCC (P < 0.001). Regarding the detection of HCC, TRX at a cut-off value of 114 ng/mL had superior diagnostic performance to AFP with an AUC of 1.000, sensitivity of 100%, and specificity of 100%, whereas AFP at a cut-off value of 20.5 ng/mL had an AUC of 1.000, sensitivity of 100%, and specificity of 47%.

Conclusion

Thioredoxin has the potential to be an HCC diagnostic marker. The clinical significance of thioredoxin in HCC requires further investigation.

Amino acids and their roles in tumor immunotherapy of breast cancer

Breast cancer is the most commonly diagnosed cancer among women. The primary treatment options include surgery, radiotherapy, chemotherapy, targeted therapy and hormone therapy. The effectiveness of breast cancer therapy varies depending on the stage and aggressiveness of the cancer, as well as individual factors. Advances in early detection and improved treatments have significantly increased survival rates for breast cancer patients. Nevertheless, specific subtypes of breast cancer, particularly triple-negative breast cancer, still lack effective treatment strategies. Thus, novel and effective therapeutic targets for breast cancer need to be explored. As substrates of protein synthesis, amino acids are important sources of energy and nutrition, only secondly to glucose. The rich supply of amino acids enables the tumor to maintain its proliferative competence through participation in energy generation, nucleoside synthesis and maintenance of cellular redox balance. Amino acids also play an important role in immune-suppressive microenvironment formation. Thus, the biological effects of amino acids may change unexpectedly in tumor-specific or oncogene-dependent manners. In recent years, there has been significant progress in the study of amino acid metabolism, particularly in their potential application as therapeutic targets in breast cancer. In this review, we provide an update on amino acid metabolism and discuss the therapeutic implications of amino acids in breast cancer.

Auranofin attenuates Schistosoma mansoni egg-induced liver granuloma and fibrosis in mice

Schistosomiasis is a serious tropical disease. Despite extensive research into the etiology of liver fibrosis, effective therapeutic options remain limited. This study aims to assess the effectiveness of auranofin in treating hepatic granuloma and fibrogenesis produced by Schistosoma (S.) mansoni eggs. Auranofin is a gold complex that contains thioglucose tetraacetate and triethylphosphine. Eighty BALB/c male mice were divided into four groups (n=20/group): negative control (GI), positive control (GII), and early (GIII) and late (GIV) treatment groups with oral auranofin according to beginning of treatment 4th week and 6th week post-infection. Mice were infected subcutaneously in a dose of 60±10 cercariae/mouse. Worm counts, egg loads, and oogram patterns were determined. Biochemical, histological, and immunostaining of interleukin-1β (IL-1β), Sirtuin 3 (SIRT3), and smooth muscle actin (SMA) were assessed. GIII showed a significant decrease in the total S. mansoni worm burden and ova/gram in liver tissue (with reduction percent of 63.07% and 78.26%, respectively). Schistosomal oogram patterns, immature and mature ova, also showed a significant decrease. The reduction in granuloma number and size was 40.63% and 48.66%, respectively, in GIII, whereas in GIV, the reduction percent was 76.63% and 67.08%. In addition, the degree of fibrosis was significantly diminished in both treated groups. GIV showed significant reduction in IL-1β and SMA expression and increase in SIRT3 expression. These findings reveal how auranofin suppresses the development of liver fibrosis. Therefore, it is crucial to take another look at auranofin as a prospective medication for the treatment of S. mansoni egg-induced hepatic granuloma and consequent fibrosis.

Low-dose radiotherapy combined with dual PD-L1 and VEGFA blockade elicits antitumor response in hepatocellular carcinoma mediated by activated intratumoral CD8+ exhausted-like T cells

Atezolizumab (anti-PD-L1) combined with bevacizumab (anti-VEGFA) is the first-line immunotherapy for advanced hepatocellular carcinoma (HCC), but the number of patients who benefit from this regimen remains limited. Here, we combine dual PD-L1 and VEGFA blockade (DPVB) with low-dose radiotherapy (LDRT), which rapidly inflames tumors, rendering them vulnerable to immunotherapy. The combinatorial therapy exhibits superior antitumor efficacy mediated by CD8+ T cells in various preclinical HCC models. Treatment efficacy relies upon mobilizing exhausted-like CD8+ T cells (CD8+ Tex) with effector function and cytolytic capacity. Mechanistically, LDRT sensitizes tumors to DPVB by recruiting stem-like CD8+ Tpex, the progenitor exhausted CD8+ T cells, from draining lymph nodes (dLNs) into the tumor via the CXCL10/CXCR3 axis. Together, these results further support the rationale for combining LDRT with atezolizumab and bevacizumab, and its clinical translation.

The molecular evaluation of thioredoxin (TXN1 & TXN2), thioredoxin reductase 1 (TXNRd1), and oxidative stress markers in a binary rat model of hypo- and hyperthyroidism after treatment with gallic acid

Oxidative stress plays an important role in the pathology of thyroid disorders. This study examined the effect of gallic acid (GA) on the oxidative status and expression of liver antioxidant genes including thioredoxin (TXN1 & TXN2) and thioredoxin reductase1 (TXNRd1) in hypo- and hyperthyroid rat models. Forty-nine male Wistar rats were randomly assigned into seven groups as follows: control group, hypothyroid and hyperthyroid groups respectively induced by propylthiouracil and levothyroxine, hypo- and hyper thyroid-treated groups (where the groups were separately treated with 50 and 100 mg/kg of GA daily, orally). The levels of thyroid hormones and serum oxidative stress markers were evaluated after 5 weeks. The relative expression of TXN1,2 and TXNRd1 genes was measured via real-time qRT-PCR. The mean level of total antioxidant capacity (TAC), malondialdehyde, and uric acid index diminished in the hypothyroid group. Increased TAC reached almost the level of control in hypothyroid groups treated with GA. Elevation of thiol index in the hypothyroid group was observed (p < 0.01), which diminished to the control level after GA treatment. The relative expression of TXN1, TXNRd1, and TXN2 genes in the hypothyroid and hyperthyroid groups significantly increased compared to the control group (p ≥ 0.05), but in the groups treated with GA, the expression of these genes declined significantly (p ≥ 0.05). Our results indicated GA can affect the expression of TXN system genes in the rat liver. Also, the results suggest GA has a more positive effect on modulating serum oxidative parameters in hypothyroid rat models than in hyperthyroid.

A Nucleotide Metabolism-Related Gene Signature for Risk Stratification and Prognosis Prediction in Hepatocellular Carcinoma Based on an Integrated Transcriptomics and Metabolomics Approach

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. The in-depth study of genes and metabolites related to nucleotide metabolism will provide new ideas for predicting the prognosis of HCC patients. This study integrated the transcriptome data of different cancer types to explore the characteristics and significance of nucleotide metabolism-related genes (NMGRs) in different cancer types. Then, we constructed a new HCC classifier and prognosis model based on HCC samples from TCGA and GEO, and detected the gene expression level in the model through molecular biology experiments. Finally, nucleotide metabolism-related products in serum of HCC patients were examined using untargeted metabolomics. A total of 97 NMRGs were obtained based on bioinformatics techniques. In addition, a clinical model that could accurately predict the prognostic outcome of HCC was constructed, which contained 11 NMRGs. The results of PCR experiments showed that the expression levels of these genes were basically consistent with the predicted trends. Meanwhile, the results of untargeted metabolomics also proved that there was a significant nucleotide metabolism disorder in the development of HCC. Our results provide a promising insight into nucleotide metabolism in HCC, as well as a tailored prognostic and chemotherapy sensitivity prediction tool for patients.

Non-alcoholic fatty liver disease and diabetes mellitus as growing aetiologies of hepatocellular carcinoma

Obesity-related complications such as non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D) are well-established risk factors for the development of hepatocellular carcinoma (HCC). This review provides insights into the molecular mechanisms that underlie the role of steatosis, hyperinsulinemia and hepatic inflammation in HCC development and progression. We focus on recent findings linking intracellular pathways and transcription factors that can trigger the reprogramming of hepatic cells. In addition, we highlight the role of enzymes in dysregulated metabolic activity and consequent dysfunctional signalling. Finally, we discuss the potential uses and challenges of novel therapeutic strategies to prevent and treat NAFLD/T2D-associated HCC.

ROS in hepatocellular carcinoma: What we know

Hepatocellular carcinoma (HCC), which is a primary liver cancer subtype, has a poor prognosis due to its high degree of malignancy. The lack of early diagnosis makes systemic therapy the only hope for HCC patients with advanced disease; however, resistance to drugs is a major obstacle. In recent years, targeted molecular therapy has gained popularity as a potential treatment for HCC. An increase in reactive oxygen species (ROS), which are cancer markers and a potential target for HCC therapy, can both promote and inhibit the disease. At present, many studies have examined targeted regulation of ROS in the treatment of HCC. Here, we reviewed the latest drugs that are still in the experimental stage, including nanocarrier drugs, exosome drugs, antibody drugs, aptamer drugs and polysaccharide drugs, to provide new hope for the clinical treatment of HCC patients.

Conceptual functional-by-design optimisation of the antioxidant capacity of trans-resveratrol, quercetin, and chlorogenic acid: Application in a functional tea

Designing functional foods as delivery systemsmay become a tailored strategy to decrease the risk of noncommunicable diseases. Therefore, this work aims to optimise a combination of t-resveratrol (RES), chlorogenic acid (CHA), and quercetin (QUE) based on antioxidant assays and develop a functional tea formulation enriched with the optimal polyphenol combination (OPM). Experimental results showed that the antioxidant capacity of these compounds is assay- and compound-dependent. A mixture containing 73% RES and 27% QUE maximised the hydroxyl radical scavenging activity and FRAP. OPM upregulated the gene expressions of heme oxygenase-1, superoxide dismutase, and catalase and decreased the reactive oxygen species generation in L929 fibroblasts. Adding OPM (100 mg/L)to a chamomile tea increased FRAP:39%, DPPH:59%; total phenolic content: 57%, iron reducing capacity: 41%, human plasma protection against oxidation: 67%. However, pasteurisation (63 °C/30 min) decreased onlythe DPPH. Combining technology, engineering, and cell biology was effective for functional tea design.

Supression Thioredoxin reductase 3 exacerbates the progression of liver cirrhosis via activation of ferroptosis pathway

AIMS

In the past decades, Txnrd3 as selenoprotein is considered to be highly expressed in testis and participate in sperm mature; however its role in liver diseases needs further study. Iron is essential for humans and animals, while its overload could damage to multiple organs. However, role of Txnrd3 and iron in cirrhosis is still unclear.

MATERIALS AND METHODS

Forty 8-week-old wild-type and forty Txnrd3-/- mice were selected to build liver cirrhosis model using Thiacetamide solution, deposition of iron in liver was observed via Prussian blue staining. Txnrd3 overexpression/knockdown model in vitro was constructed based on cell transfection techniques in AML12 cells, expression abundance of ferroptosis pathway genes within cells and tissues were determined by qRT-PCR and Western Blot.

KEY FINDINGS

Results showed that Txnrd3-/- mice developed more pronounced liver damage, accompanied by reduced GPX4 expression and iron deposition. A significant decrease in the expression abundance of GPX4 was also detected in Txnrd3 knock-down AML12 cells. In summary, Txnrd3 knockdown could result in iron overload and ferroptosis pathway activation within liver tissues and hepatocytes, ultimately lead to the occurrence of liver injury and cirrhosis.

SIGNIFICANCE

These results will provide biological markers for early diagnosis during cirrhosis and lay a theoretical basis for clinical therapy.

From liver fibrosis to hepatocarcinogenesis: Role of excessive liver H2O2 and targeting nanotherapeutics

Liver fibrosis and hepatocellular carcinoma (HCC) have been worldwide threats nowadays. Liver fibrosis is reversible in early stages but will develop precancerosis of HCC in cirrhotic stage. In pathological liver, excessive H₂O₂ is generated and accumulated, which impacts the functionality of hepatocytes, Kupffer cells (KCs) and hepatic stellate cells (HSCs), leading to genesis of fibrosis and HCC. H₂O₂ accumulation is associated with overproduction of superoxide anion (O₂^•−) and abolished antioxidant enzyme systems. Plenty of therapeutics focused on H₂O₂ have shown satisfactory effects against liver fibrosis or HCC in different ways. This review summarized the reasons of liver H₂O₂ accumulation, and the role of H₂O₂ in genesis of liver fibrosis and HCC. Additionally, nanotherapeutics targeting H₂O₂ were summarized for further consideration of antifibrotic or antitumor therapy.

•

Liver fibrosis and HCC are closely related because ROS induced liver damage and inflammation, especially over-cumulated H₂O₂.

•

Excess H₂O₂ diffusion in pathological liver was due to increased metabolic rate and diminished cellular antioxidant systems.

•

Freely diffused H₂O₂ damaged liver-specific cells, thereby leading to fibrogenesis and hepatocarcinogenesis.

•

Nanotherapeutics targeting H₂O₂ are summarized for treatment of liver fibrosis and HCC, and also challenges are proposed.

Calycosin-7-glucoside promotes mitochondria-mediated apoptosis in hepatocellular carcinoma by targeting thioredoxin 1 to regulate oxidative stress

Thioredoxin1 (TRX1) is a key protein that regulates redox and is considered to be a key target for cancer therapy. Flavonoids have been proven to have good antioxidant and anticancer activities. This study aimed to investigate whether the flavonoid calycosin-7-glucoside (CG) exerts an anti-hepatocellular carcinoma (HCC) role by targeting TRX1. Different doses of CG were used to treat HCC cell lines Huh-7 and HepG2 to calculate the IC₅₀. On this basis, the effects of low, medium and high doses of CG on cell viability, apoptosis, oxidative stress and TRX1 expression of HCC cells were investigated in vitro. Also, HepG2 xenograft mice were used to evaluate the role of CG on HCC growth in vivo. The binding mode of CG and TRX1 was explored by molecular docking. Then si-TRX1 was used to further discover the effects of TRX1 on CG inhibition of HCC. Results found that CG dose-dependent decreased the proliferation activity of Huh-7 and HepG2 cells, induced apoptosis, significantly activated oxidative stress and inhibited TRX1 expression. In vivo experiments also showed that CG dose-dependent regulated oxidative stress and TRX1 expression, and promoted the expression of apoptotic proteins to inhibit HCC growth. Molecular docking confirmed that CG had a good binding effect with TRX1. Intervention with TRX1 significantly inhibited the proliferation of HCC cells, promoted apoptosis, and further promoted the effect of CG on the activity of HCC cells. In addition, CG significantly increased ROS production, reduced mitochondrial membrane potential, regulated the expression of Bax, Bcl-2 and cleaved-caspase-3, and activated mitochondria-mediated apoptosis. And si-TRX1 enhanced the effects of CG on mitochondrial function and apoptosis of HCC, suggesting that TRX1 participated in the inhibitory effect of CG on mitochondria-mediated apoptosis of HCC. In conclusion, CG exerts anti-HCC activity by targeting TRX1 to regulate oxidative stress and promote mitochondria-mediated apoptosis.

Ferroptosis in colorectal cancer: a future target?

Colorectal cancer (CRC) is the third leading cause of cancer deaths worldwide and is characterised by frequently mutated genes, such as APC, TP53, KRAS and BRAF. The current treatment options of chemotherapy, radiation therapy and surgery are met with challenges such as cancer recurrence, drug resistance, and overt toxicity. CRC therapies exert their efficacy against cancer cells by activating biological pathways that contribute to various forms of regulated cell death (RCD). In 2012, ferroptosis was discovered as an iron-dependent and lipid peroxide-driven form of RCD. Recent studies suggest that therapies which target ferroptosis are promising treatment strategies for CRC. However, a greater understanding of the mechanisms of ferroptosis initiation, propagation, and resistance in CRC is needed. This review provides an overview of recent research in ferroptosis and its potential role as a therapeutic target in CRC. We also propose future research directions that could help to enhance our understanding of ferroptosis in CRC.

Tumor-Targeting NHC-Au(I) Complex Induces Immunogenic Cell Death in Hepatocellular Carcinoma

Immunogenic cell death (ICD) is a promising direction of cancer immunotherapy in hepatocellular carcinoma (HCC). A series of novel NHC-Au(I) complexes derived from 4,5-diarylimidazole, containing glycyrrhetinic acid (GA) as an efficient targeting ligand for HCC, were herein designed and synthesized. Among these, complex 4C exhibited excellent effectiveness for tumor targeting and antitumor activity, which induced the occurrence of ICD in HCC cells. Additionally, 4C can effectively inhibit TrxR enzyme activity, increase reactive oxygen species (ROS) expression, lead to redox homeostasis disorder, mediate mitochondrial dysfunction and endoplasmic reticulum stress (ERS), and cause the characteristic discharge of damage-associated molecular patterns (DAMPs) in HCC cells. More importantly, 4C showed a great ICD-inducing effect in a vaccination mouse model and activated antitumor immunity in a tumor-bearing C57BL/6 mouse model, which is consistent with the in vitro results. In conclusion, we found the potential of Au(I) complex with HCC-targeted capability for effective tumor immunotherapy.

The advancements in targets for ferroptosis in liver diseases

Ferroptosis is a type of regulated cell death caused by iron overload and lipid peroxidation, and its core is an imbalance of redox reactions. Recent studies showed that ferroptosis played a dual role in liver diseases, that was, as a therapeutic target and a pathogenic factor. Therefore, herein, we summarized the role of ferroptosis in liver diseases, reviewed the part of available targets, such as drugs, small molecules, and nanomaterials, that acted on ferroptosis in liver diseases, and discussed the current challenges and prospects.

A prognostic risk model, tumor immune environment modulation, and drug prediction of ferroptosis and amino acid metabolism-related genes in hepatocellular carcinoma

The prognosis of hepatocellular carcinoma (HCC) is challenging due to its heterogeneity. Ferroptosis and amino acid metabolism have been shown to be closely related to HCC. We obtained HCC-related expression data from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. We then crossed differentially expressed genes (DEGs), amino acid metabolism genes, and ferroptosis-related genes (FRGs) to obtain amino acid metabolism-ferroptosis-related differentially expressed genes (AAM-FR DEGs). Moreover, we developed a prognostic model using Cox analysis, followed by a correlation analysis of risk scores with clinical characteristics. We also performed an immune microenvironment analysis and drug sensitivity analysis. Finally, the expression levels of model genes were verified by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical assays. We found that the 18 AAM-FR DEGs were mainly enriched to the alpha-amino acid metabolic process and amino acid biosynthesis pathways. Cox analysis identified CBS, GPT2, SUV39H1, and TXNRD1 as prognostic biomarkers for the risk model construction. Our results showed that the risk scores differed between pathology stage, pathology T stage, and HBV, and the number of HCC patients in the two groups. In addition, the expression of PD-L1 and CTLA-4 was high in the high-risk group, and the half-maximal inhibitory concentration (IC50) of sorafenib also differed between the two groups. Finally, the experimental validation demonstrated that the expression of biomarkers was consistent with the study analysis. Therefore, in this study, we constructed and validated a prognostic model (CBS, GPT2, SUV39H1, and TXNRD1) related to ferroptosis and amino acid metabolism and examined their prognostic value for HCC.

Nanoparticles for cancer therapy: a review of influencing factors and evaluation methods for biosafety

Nanoparticles are widely used in the biomedical field for diagnostic and therapeutic purposes due to their small size, high carrier capacity, and ease of modification, which enable selective targeting and as contrast agents. Over the past decades, more and more nanoparticles have received regulatory approval to enter the clinic, more nanoparticles have shown potential for clinical translation, and humans have increasing access to them. However, nanoparticles have a high potential to cause unpredictable adverse effects on human organs, tissues, and cells due to their unique physicochemical properties and interactions with DNA, lipids, cells, tissues, proteins, and biological fluids. Currently, issues, such as nanoparticle side effects and toxicity, remain controversial, and these pitfalls must be fully considered prior to their application to body systems. Therefore, it is particularly urgent and important to assess the safety of nanoparticles acting in living organisms. In this paper, we review the important factors influencing the biosafety of nanoparticles in terms of their properties, and introduce common methods to summarize the biosafety evaluation of nanoparticles through in vitro and in body systems.

Potential Treatment Strategies for Hepatocellular Carcinoma Cell Sensitization to Sorafenib

Liver cancer is highly malignant, has a low sensitivity to chemotherapy, and is associated with poor patient prognosis. The last 3 years have seen the emergence of promising targeted therapies for the treatment of hepatocellular carcinoma (HCC). For over 10 years, before the discovery of lenvatinib, sorafenib was only first-line therapeutic agent available for the treatment of advanced HCC. However, several clinical studies have shown that a considerable proportion liver cancer patients are insensitive to sorafenib. Very few patients actually substantially benefit from treatment with sorafenib, and the overall efficacy of the drug has not been satisfactory; therefore, sorafenib has attracted considerable research attention. This study, which is based on previous studies and reports, reviews the potential mechanisms underlying sorafenib resistance and summarizes combination therapies and potential drugs that can be used to sensitize HCC cells to sorafenib.

Upregulated SSB Is Involved in Hepatocellular Carcinoma Progression and Metastasis through the Epithelial-Mesenchymal Transition, Antiapoptosis, and Altered ROS Level Pathway

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with high morbidity and mortality. Therefore, finding new diagnostic and therapeutic targets is vital for HCC patients. Recent studies have shown that dysregulation of RNA-binding proteins is often associated with cancer progression. Several studies have reported that the RNA-binding protein SSB can promote cancer occurrence and progression and is linked to tumor epithelial-mesenchymal transition (EMT), which could be a new diagnostic marker and therapeutic target. However, the expression and function of SSB in HCC remain to be elucidated. Therefore, this study is aimed at clarifying the expression and biological function of SSB in HCC through bioinformatics analysis combined with in vitro experiments. We found that SSB is highly expressed in HCC and is associated with the poor prognosis of HCC patients, and it can serve as an independent unfavorable prognostic factor. Knockdown of SSB can inhibit the growth of HCC cells in vitro, increase the level of apoptosis and the expression of pro-apoptosis-related proteins, and decrease the expression of antiapoptotic proteins. Meanwhile, SSB knockdown reduced HCC cell invasiveness, and the expression of EMT-related proteins changed significantly. We also found that the gene SSB was associated with the level of oxidative stress in liver cancer cells, and the level of intracellular reactive oxygen species (ROS) increased after knockdown of SSB. The results of bioinformatics analysis also showed that high expression of SSB may affect the effect of checkpoint blockade (ICB) therapy. In conclusion, we found that SSB is highly expressed in HCC and that upregulated SSB can promote the proliferation and metastasis of HCC through antiapoptotic, altered intracellular oxidative stress level, and EMT pathways, which can serve as a new diagnostic marker and therapeutic target, and patients with high SSB expression may not have obvious ICB therapy effect.

New Insights into the Behavior of NHC-Gold Complexes in Cancer Cells

Among the non-platinum antitumor agents, gold complexes have received increased attention owing to their strong antiproliferative effects, which generally occur through non-cisplatin-like mechanisms of action. Several studies have revealed that many cytotoxic gold compounds, such as N-heterocyclic carbene (NHC)-gold(I) complexes, are potent thioredoxin reductase (TrxR) inhibitors. Many other pathways have been supposed to be altered by gold coordination to protein targets. Within this frame, we have selected two gold(I) complexes based on aromatic ligands to be tested on cancer cells. Differently from bis [1,3-diethyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]gold(I) bromide (Au4BC), bis [1-methyl-3-acridineimidazolin-2-ylidene]gold(I) tetrafluoroborate (Au3BC) inhibited TrxR1 activity in vitro. Treatment of Huh7 hepatocellular carcinoma (HCC) cells, and MDA-MB-231 triple-negative breast cancer (TNBC) cells, with Au4BC inhibited cell viability, increased reactive oxygen species (ROS) levels, caused DNA damage, and induced autophagy and apoptosis. Notably, we found that, although Au3BC inhibited TrxR1 activity, no effect on the cell viabilities of HCC and BC cells was observed. At the molecular level, Au3BC induced a protective response mechanism in Huh7 and MDA-MB-231 cells, by inducing up-regulation of RAD51 and p62 protein expression, two proteins involved in DNA damage repair and autophagy, respectively. RAD51 gene knock-down in HCC cells increased cell sensitivity to Au3BC by significant reduction of cell viability, induction of DNA damage, and induction of apoptosis and autophagy. All together, these results suggest that the tested NHC-Gold complexes, Au3BC and Au4BC, showed different mechanisms of action, either dependent or independent of TrxR1 inhibition. As a result, Au3BC and Au4BC were found to be promising candidates as anticancer drugs for the treatment of HCC and BC.

Ca2+-Dependent Effects of the Selenium-Sorafenib Nanocomplex on Glioblastoma Cells and Astrocytes of the Cerebral Cortex: Anticancer Agent and Cytoprotector

Despite the fact that sorafenib is recommended for the treatment of oncological diseases of the liver, kidneys, and thyroid gland, and recently it has been used for combination therapy of brain cancer of various genesis, there are still significant problems for its widespread and effective use. Among these problems, the presence of the blood-brain barrier of the brain and the need to use high doses of sorafenib, the existence of mechanisms for the redistribution of sorafenib and its release in the brain tissue, as well as the high resistance of gliomas and glioblastomas to therapy should be considered the main ones. Therefore, there is a need to create new methods for delivering sorafenib to brain tumors, enhancing the therapeutic potential of sorafenib and reducing the cytotoxic effects of active compounds on the healthy environment of tumors, and ideally, increasing the survival of healthy cells during therapy. Using vitality tests, fluorescence microscopy, and molecular biology methods, we showed that the selenium-sorafenib (SeSo) nanocomplex, at relatively low concentrations, is able to bypass the mechanisms of glioblastoma cell chemoresistance and to induce apoptosis through Ca²⁺-dependent induction of endoplasmic reticulum stress, changes in the expression of selenoproteins and selenium-containing proteins, as well as key kinases-regulators of oncogenicity and cell death. Selenium nanoparticles (SeNPs) also have a high anticancer efficacy in glioblastomas, but are less selective, since SeSo in cortical astrocytes causes a more pronounced activation of the cytoprotective pathways.

Omics-based identification of an NRF2-related auranofin resistance signature in cancer: Insights into drug repurposing

Auranofin is a thioredoxin reductase-1 inhibitor originally approved for the treatment of rheumatoid arthritis. Recently, auranofin has been repurposed as an anticancer drug, with pharmacological activity reported in multiple cancer types. In this study, we characterized transcriptional and genetic alterations associated with auranofin response in cancer. By integrating data from an auranofin cytotoxicity screen with transcriptome profiling of lung cancer cell lines, we identified an auranofin resistance signature comprising 29 genes, most of which are classical targets of the transcription factor NRF2, such as genes involved in glutathione metabolism (GCLC, GSR, SLC7A11) and thioredoxin system (TXN, TXNRD1). Pan-cancer analysis revealed that mutations in NRF2 pathway genes, namely KEAP1 and NFE2L2, are strongly associated with overexpression of the auranofin resistance gene set. By clustering cancer types based on auranofin resistance signature expression, hepatocellular carcinoma, and a subset of non-small cell lung cancer, head-neck squamous cell carcinoma, and esophageal cancer carrying NFE2L2/KEAP1 mutations were predicted resistant, whereas leukemia, lymphoma, and multiple myeloma were predicted sensitive to auranofin. Cell viability assays in a panel of 20 cancer cell lines confirmed the augmented sensitivity of hematological cancers to auranofin; an effect associated with dependence upon glutathione and decreased expression of NRF2 target genes involved in GSH synthesis and recycling (GCLC, GCLM and GSR) in these cancer types. In summary, the omics-based identification of sensitive/resistant cancers and genetic alterations associated with these phenotypes may guide an appropriate repurposing of auranofin in cancer therapy.

Optimization of the Solvent and In Vivo Administration Route of Auranofin in a Syngeneic Non-Small Cell Lung Cancer and Glioblastoma Mouse Model

The antineoplastic activity of the thioredoxin reductase 1 (TrxR) inhibitor, auranofin (AF), has already been investigated in various cancer mouse models as a single drug, or in combination with other molecules. However, there are inconsistencies in the literature on the solvent, dose and administration route of AF treatment in vivo. Therefore, we investigated the solvent and administration route of AF in a syngeneic SB28 glioblastoma (GBM) C57BL/6J and a 344SQ non-small cell lung cancer 129S2/SvPasCrl (129) mouse model. Compared to daily intraperitoneal injections and subcutaneous delivery of AF via osmotic minipumps, oral gavage for 14 days was the most suitable administration route for high doses of AF (10-15 mg/kg) in both mouse models, showing no measurable weight loss or signs of toxicity. A solvent comprising 50% DMSO, 40% PEG300 and 10% ethanol improved the solubility of AF for oral administration in mice. In addition, we confirmed that AF was a potent TrxR inhibitor in SB28 GBM tumors at high doses. Taken together, our results and results in the literature indicate the therapeutic value of AF in several in vivo cancer models, and provide relevant information about AF's optimal administration route and solvent in two syngeneic cancer mouse models.

Single-cell RNA sequencing reveals resident progenitor and vascularization-associated cell subpopulations in rat annulus fibrosus

Background

One of the main causes of low back pain is intervertebral disc degeneration (IDD). Annulus fibrosus (AF) is important for the integrity and functions of the intervertebral disc (IVD). However, the resident functional cell components such as progenitors and vascularization-associated cells in AF are yet to be fully identified.

Purpose

Identification of functional AF cell subpopulations including resident progenitors and vascularization-associated cells.

Methods

In this study, the single-cell RNA sequencing data of rat IVDs from a public database were analyzed using Seurat for cell clustering, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) for functional analysis, StemID for stem cell identification, Monocle and RNA velocity for pseudotime differentiation trajectory validation, single-cell regulatory network inference and clustering (SCENIC) for gene regulatory network (GRN) analysis, and CellChat for cell-cell interaction analysis. Immunostaining on normal and degenerated rat IVDs, as well as human AF, was used for validations.

Results

From the data analysis, seven AF cell clusters were identified, including two newly discovered functional clusters, the Grem1 ⁺ subpopulation and the Lum ⁺ ​subpopulation. The Grem1 ⁺ subpopulation had progenitor characteristics, while the Lum ⁺ ​subpopulation was associated with vascularization during IDD. The GRN analysis showed that Sox9 and Id1 were among the key regulators in the Grem1 ⁺ subpopulation, and Nr2f2 and Creb5 could be responsible for the vascularization function in the Lum ⁺ ​subpopulation. Cell-cell interaction analysis revealed highly regulated cellular communications between these cells, and multiple signaling networks including PDGF and MIF signaling pathways were involved in the interactions.

Conclusions

Our results revealed two new functional AF cell subpopulations, with stemness and vascularization induction potential, respectively.

The Translational potential of this article

These findings complement our knowledge about IVDs, especially the AF, and in return provide potential cell source and regulation targets for IDD treatment and tissue repair. The existence of the cell subpopulations was also validated in human AF, which strengthen the clinical relevance of the findings.