Oxidative Stress in Cancer

Structural simplification of quaternary benzophenanthridine alkaloids generating a candidate for the treatment of non-small cell lung cancer

Quaternary benzophenanthridine alkaloids (QBAs), such as sanguinarine, chelerythrine, and nitidine, possess diverse pharmacological activities. This study presents a simplified structure for QBAs, yielding twelve three-membered phenanthridine alkaloids. Notably, compound 6f demonstrates enhanced potency in selectively inhibiting thioredoxin reductase (TrxR, TXNRD) and exhibits significant cytotoxicity against non-small cell lung cancer (NSCLC) cells. While TrxR is a selenoenzyme, many of its inhibitors react with biological thiols; however, 6f shows minimal reactivity with thiols such as glutathione (GSH) and cysteine. Mechanistic investigations reveal that 6f stimulates reactive oxygen species production, reduces intracellular thiols, and decreases the GSH/GSSG ratio, leading to cell apoptosis through oxidative stress. Moreover, significant tumor regression has been observed in nude mice with NSCLC following treatment with 6f. The pronounced anticancer activity and possible mechanism of action of 6f suggest its potential as a candidate for further development in NSCLC therapy.

The critical role of the Hippo signaling pathway in renal fibrosis

Renal fibrosis is a fundamental pathological change in the progression of various chronic kidney diseases to the end stage of renal disease. The Hippo signaling pathway is an evolutionary highly conserved signaling pathway that is involved in the regulation of organ size, tissue regeneration, and human reproduction and development. Currently, many studies have shown that it is closely associated with renal diseases, such as, renal fibrosis, diabetic nephropathy, and renal cancer. Here, we review the current researches on the effect of Hippo signaling pathway on renal fibrosis, which provides new ideas and theoretical basis for clinical therapeutics of renal fibrosis.

Inhalable DNase I@Au hybrid nanoparticles for radiation sensitization and metastasis inhibition by elimination of neutrophil extracellular traps

High-dose radiation therapy is a widely used clinical strategy to inhibit tumor growth. However, the rapid generation of excessive reactive oxygen species (ROS) triggers the formation of neutrophil extracellular traps (NETs), which capture free tumor cells in the bloodstream, promoting metastasis. In this study, we developed a hybrid nanoparticle composed of DNase I and gold (DNase I@Au) to enhance radiotherapy efficacy while mitigating metastasis by precisely eliminating NETs. The DNase I@Au nanoparticles, administered via aerosol inhalation, are efficiently delivered to lung tumor tissue, improving radiosensitization and reducing tumor size. Crucially, the nanoparticles could gradually release DNase I, effectively degrading ROS-induced NETs and preventing the interaction of free malignant cells with tumor sites or vasculature, thereby inhibiting metastasis. Therefore, we provide an enzyme and sensitizer co-loaded strategy that offers a promising approach to improve the therapeutic outcome of radiotherapy and reduce the risk of lung cancer metastasis under ROS stimulation.

Metabolic dysfunction-associated steatotic liver disease: A sexually dimorphic disease and breast and gynecological cancer

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become a global public health and economic burden worldwide in the past few decades. Epidemiological studies have shown that MASLD is a multisystem disease that is associated not only with liver-related complications but also with an increased risk of developing extrahepatic cancers. MASLD is a sexually dimorphic disease with sex hormones playing an important role in the development and progression of MASLD, especially by the levels and ratios of circulating estrogens and androgens. MASLD is associated with hormone-sensitive cancers including breast and gynecological cancer. The risk of breast and gynecological cancer is elevated in individuals with MASLD driven by shared metabolic risk factors including obesity and insulin resistance. Multiple potential mechanisms underline these associations including metabolic dysfunction, gut dysbiosis, chronic inflammation and dysregulated release of hepatokines. However, the effect of hormone therapy including hormone replacement therapy and anti-estrogen treatment on MASLD and female-specific cancers remains debatable at this time. This synopsis will review the associations between MASLD and breast and gynecological cancer, their underlying mechanisms, implications of hormonal therapies, and their future directions.

Sulforaphane downregulates mitochondrial TIGAR via inhibiting mitochondrial transmembrane assembly and LONP1/CASP3 axis causing apoptosis

TP53-induced glycolysis and apoptosis regulator (TIGAR) was implicated to be a brand-new target for sulforaphane (SFN) in human non-small cell lung cancer (NSCLC), while the mechanism was elusive. We found that highly expressed TIGAR was positively correlated to pathological grading and contributed to poor survival in NSCLC patients. Western blot showed that SFN downregulated α-tubulin, TIGAR, Timm23 and Timm17A in cytosolic and/or mitochondrial lysate. Besides, SFN downregulated α-tubulin contributing to TIGAR reduction, and also decreased interactions of α-tubulin to Timm23, Timm17A and TIGAR in mitochondria; thus, SFN disrupted the microtubule-mediated mitochondrial transmembrane complexes blocking the entry of cytosolic TIGAR into mitochondria. Further, SFN downregulated mitoprotease LONP1 and decreased the binding of LONP1 to TIGAR; knockdown of LONP1 activated mitochondrial caspase-3 causing the cleavage of mitochondrial TIGAR; SFN-mediated the reduction of TIGAR decreased NADPH leading to ROS elevation and apoptosis in NSCLC. These studies will provide key targets for anti-NSCLC therapy.

Current knowledge on the mechanisms underpinning vasculogenic mimicry in triple negative breast cancer and the emerging role of nitric oxide

Vasculogenic mimicry (VM) is the process by which cancer cells form vascular-like channels to support their growth and dissemination. These channels lack endothelial cells and are instead lined by the tumour cells themselves. VM was first reported in uveal melanomas but has since been associated with other aggressive solid tumours, such as triple-negative breast cancer (TNBC). In TNBC patients, VM is associated with tumour aggressiveness, drug resistance, metastatic burden, and poor prognosis. The lack of effective targeted therapies for TNBC has stimulated research on the mechanisms underpinning VM in order to identify novel druggable targets. In recent years, studies have highlighted the role of nitric oxide (NO), the NO synthesis inhibitor, asymmetric dimethylarginine (ADMA), and dimethylarginine dimethylaminohydrolase 1 (DDAH1), the key enzyme responsible for ADMA metabolism, in regulating VM. Specifically, NO inhibition through downregulation of DDAH1 and consequent accumulation of ADMA appears to be a promising strategy to suppress VM in TNBC. This review discusses the current knowledge regarding the molecular pathways underpinning VM in TNBC, anti-VM therapies under investigation, and the emerging role of NO regulation in VM.

Mechanisms of radioresistance and radiosensitization strategies for Triple Negative Breast Cancer

Breast cancer is one of the most common malignant tumors in women. Triple-negative breast cancer (TNBC) is a molecular subtype of breast cancer that is characterized by a high risk of recurrence and poor prognosis. With the increasingly prominent role of radiotherapy in TNBC treatment, patient resistance to radiotherapy is an attractive area of clinical research. Gene expression changes induced by multiple mechanisms can affect the radiosensitivity of TNBC cells to radiotherapy through a variety of ways, and the enhancement of radioresistance is an important factor in the malignant progression of TNBC. The above pathways mainly include DNA damage repair, programmed cell death, cancer stem cells (CSC), antioxidant function, tumor microenvironment, and epithelial-mesenchymal transition (EMT) pathway. Tumor cells can reduce the damage of radiotherapy to themselves through the above ways, resulting in radioresistance. Therefore, in this review, we aim to summarize the strategies for immunotherapy combined with radiotherapy, targeted therapy combined with radiotherapy, and epigenetic therapy combined with radiotherapy to identify the best treatment for TNBC and improve the cure and survival rates of patients with TNBC. This review will provide important guidance and inspiration for the clinical practice of radiotherapy for TNBC, which will help deepen our understanding of this field and promote its development.

Targeting hypoxia-mediated chemo-immuno resistance by a hybrid NBDHEX-Pt(IV) prodrug via declining nuclear STING1-promoted AhR-CIN in human lung squamous cell carcinoma

As found in human lung squamous cell carcinoma (LUSC), STING1 involved in ER-Golgi intermediate compartment (ERGIC) could coordinate immune responses to ectopic DNA triggered by DNA-targeted chemotherapy. ERGIC STING1 is considered to compete with nuclear STING1 to decline aryl hydrocarbon receptor (AhR)-chromosomal instability (CIN)-triggered chronic STING activation which could cause therapeutic resistance. Moreover, GSTP1 was proved to inhibit ERGIC-STING1 via promoting S-glutathione modification of STING1. Hence, a potent GSTP1-targeted Pt(IV) hybrid NBDHEX-DN604, was designed via conjugating a GSTP1 inhibitor NBDHEX to the axial position of Pt(IV) prodrug. As mentioned, hypoxia is mainly observed in malignant tumors and develops acquired drug resistance. In vitro bio-properties of hypoxic SK-MES-1/cDDP cells demonstrated that NBDHEX-DN604 could reverse chemo-immuno resistance via intercepting GSTP1 to activate ERGIC STING1, leading to the decrease of nuclear STING1. The mechanistic data indicated that NBDHEX-DN604 could elevate ERGIC STING1 to mitigate nuclear STING1-mediated AhR-TLS-CIN-chronic activation. Meanwhile, NBDHEX-DN604 was found to decline STING1-AhR-CIN to circumvent chemo-immuno resistance, resulting in predominant in vivo antitumor effect in HY-KLN-205/cDDP-inoculated BALB/c mice. The data provide a novel rationale for the mixed chemo-immunotherapy of NBDHEX-DN604 as a potent Pt(IV) therapeutic method for patients with resistant LUSC.

Interaction between redox regulation, immune activation, and response to treatment in HER2+ breast cancer

In HER2+ breast cancer (BC), neoadjuvant therapy represents an ideal scenario for translational research, considering pathological complete response (pCR) as an endpoint. In these patients, achieving pCR after neoadjuvant therapy is associated with a better prognosis. However, biomarkers are needed to tailor optimal treatment for each patient. Evaluating tumour-infiltrating lymphocytes (TILs) has gained attention in predicting pCR. In the context of metastatic disease, TILs also appear to play a role in predicting outcomes. The interaction between the presence of TILs and reactive oxygen species (ROS) remains an area to be explored. ROS are critical for tumour cell homeostasis, and different levels can trigger differential biological responses in cancer cells and their microenvironment. Nevertheless, the influence of ROS on treatment efficacy and prognosis in patients with HER2+ BC remains to be elucidated. In this article, we reviewed the interplay between treatment response, immune system activation, and ROS production in HER2+ BC and suggested novel areas of intervention and research. We also present a bioinformatic analysis demonstrating that the altered expression of several redox-related genes could be associated with the prevalence of immune cell populations in the tumour microenvironment and with patient survival. New biomarkers are thus suggested and should be further explored to tailor the best treatment to each patient.

Urolithin D: A promising metabolite of ellagitannin in combatting oxidative stress

The objective of this research is to examine the function of urolithin D (UroD, 3,4,8,9-tetrahydroxy-6H-benzo[c]chromen-6-one), a metabolite obtained from ellagitannins, in the mitigation of oxidative stress. The research is based on estimating the mechanisms through which UroD acts as an antioxidant under physiological conditions, emphasizing standard antioxidant mechanisms such as formal Hydrogen Aatom Transfer (f-HAT), Radical Adduct Formation (RAF)/Radical Coupling Formation (RCF), and Single Electron Transfer followed by Proton Transfer (SET-PT). This study utilised advanced quantum mechanical techniques, specifically density functional theory (DFT) and the Quantum Mechanics-based test for Overall free Radical Scavenging activity (QM-ORSA) methodology, to assess the thermodynamic and kinetic parameters of UroD in the presence of reactive radical species HOO•, CH3OO• and CCl3OO•. The estimated overall rate constants (koverall) indicate a reactivity order of CCl3OO• (koverall = 2.06 × 1010 M-1s-1) > HOO• (koverall = 2.59 × 109 M-1s-1) > CH3OO• (koverall = 1.89 × 109 M-1s-1). The examination of the relative proportions of products (%) indicates that UroD exhibits antiradical action primarily through all examined mechanisms, with the predominant involvement of mononion and dianion acid-base species. In addition to its capacity to directly counteract ROS, UroD can restore oxidative DNA damage, specifically targeting oxidative byproducts commonly associated with 2-deoxyguanosine (2 dG), which are susceptible to oxidative stress. The UroD regenerates G-centered radical cations (2 dG•+) through the SET mechanism, C-centered radicals (2 dG•) in the sugar moiety through f-HAT, and repairs i-OH-2dG lesions through sequential hydrogen atom transfer dehydration (SHATD). Additionally, the radical products formed during antioxidant action can be regenerated in the presence of O2•- into anionic species, which are subsequently protonated into neutral species that can re-engage in antioxidant activity. These findings underscore the efficiency of UroD in scavenging free radicals and suggest its potential role in preserving cellular integrity and protecting against oxidative stress-related diseases.

Glutaminase-1 Mediated Glutaminolysis to Glutathione Synthesis Maintains Redox Homeostasis and Modulates Ferroptosis Sensitivity in Cancer Cells

Glutaminase-1 (GLS1) has garnered considerable interest as a metabolic target in cancer due to its heightened involvement and activity. However, the precise fate of glutaminolysis catalysed by GLS1 in cancer cells remains elusive. We found that GLS1 knockout led to significant suppression of cancer cell proliferation, which can be reversed or partially restored by supplementation of glutamate or non-essential amino acids that can be converted into glutamate. The addition of spliceosomal KGA or GAC ameliorates cancer cell growth in vitro and in vivo, providing both simultaneously completely reverse the effect. The primary metabolic fate of glutamate produced through glutaminolysis in cancer cells is mainly used to produce glutathione (GSH) for redox homeostasis, not entering the tricarboxylic acid cycle or synthesising nucleotides. GSH monoethyl ester (GSH-MEE) effectively rescues the inhibition of cancer cell proliferation caused by GLS1 knockout. Deletion of GLS1 results in an elevation of reactive oxygen species (ROS) and malondialdehyde (MDA), a reduction of NADPH/NADP+ ratio, and an augmented susceptibility of cells to ferroptosis. Glutathione Peroxidase 4 (GPX4) and GPX1 exhibit complementary roles in redox regulation, with GLS1 knockout promoting GPX4 degradation. Pharmacological inhibition of GLS1 synergises with GPX4 inhibitor to suppress tumour growth. Dual targeting of GPX4 and GPX1 presents a potent anti-cancer strategy. This metabolic mechanism facilitates a deeper comprehension of the abnormal glutamine metabolism in cancer cells, establishing a theoretical basis for the potential clinical utilisation of GLS1 inhibitors and presenting novel perspectives for advancing combinatorial therapeutic approaches.

Redox-driven hybrid nanoenzyme dynamically activating ferroptosis and disulfidptosis for hepatocellular carcinoma theranostics

Hepatocellular carcinoma (HCC) presents formidable therapeutic challenges due to its pronounced metabolic heterogeneity, particularly arising from spatially uneven glucose availability within the tumor microenvironment (TME). To address this, we developed a glutathione (GSH)-responsive, biomimetic hybrid nanoenzyme system (M@GOx/Fe-HMON) composed of hollow mesoporous organosilica nanoparticles co-loaded with glucose oxidase (GOx) and Fe2+/Fe3+ redox pairs, and cloaked in homologous tumor cell membranes for enhanced targeting. In glucose-rich regions, the nanoenzyme orchestrates a GOx-peroxidase (POD) cascade that produces reactive oxygen species (ROS) via the Fenton reaction, leading to ferroptosis through intensified oxidative stress and GSH depletion. Conversely, under glucose-deficient conditions, the nanoenzyme promotes disulfidptosis by aggravating glucose deprivation, depleting nicotinamide adenine dinucleotide phosphate (NADPH), and impairing cystine metabolism, ultimately resulting in actin cytoskeletal collapse. This dual-action platform dynamically adapts to the tumor's metabolic landscape, selectively inducing ferroptosis or disulfidptosis according to glucose levels, disrupting redox homeostasis and amplifying antitumor efficacy. Notably, this study is the first to integrate ferroptosis and disulfidptosis activation into a single, metabolism-sensitive nanoenzyme system, providing a novel paradigm for exploiting tumor metabolic heterogeneity. Furthermore, the combination of endogenous metabolic regulation with magnetic resonance imaging (MRI)-guided diagnosis introduces an innovative and noninvasive strategy for precision cancer theranostics.

B-Lymphoid Tyrosine Kinase Crosslinks Redox and Apoptosis Signaling Networks to Promote the Survival of Transplanted Bone Marrow Mesenchymal Stem Cells

Stress-induced apoptosis presents an obstacle to bone marrow mesenchymal stem cell (BMSC) transplantation to repair steroid-induced osteonecrosis of the femoral head (SONFH). Thus, appropriate intervention strategies should be explored to mitigate this. In our previous study, we discovered a new subgroup of BMSCs-the oxidative stress-resistant BMSCs (OSR-BMSCs)-which can survive the oxidative stress microenvironment in the osteonecrotic area, through a mechanism that currently remains unclear. In this study, we found that B-lymphoid tyrosine kinase (BLK) may be the crucial factor regulating the oxidative stress resistance of OSR-BMSCs, as it is highly expressed in these cells. Knockdown of BLK eliminated oxidative stress resistance, aggravated oxidative stress-induced apoptosis, reduced the survival of OSR-BMSCs in the oxidative stress microenvironment of the osteonecrotic area, and greatly weakened the transplantation efficacy of OSR-BMSCs for SONFH. By contrast, BLK was weakly expressed in oxidative stress-sensitive BMSCs (OSS-BMSCs). Overexpression of BLK in susceptible OSS-BMSCs allowed them to acquire oxidative stress resistance, inhibited oxidative stress-induced apoptosis, promoted their survival in the osteonecrotic area, and improved the transplantation efficacy of OSS-BMSCs for SONFH. Mechanistically, BLK concurrently activates redox and apoptotic signaling networks through its tyrosine kinase activity, which confers oxidative stress resistance to BMSCs and inhibits their stress-induced apoptosis of BMSCs. Herein, we report that OSR-BMSCs have intrinsic oxidative stress resistance that is conferred and mediated by BLK. This finding provides a potential new intervention strategy for improving the survival of transplanted BMSCs and the therapeutic efficacy of BMSC transplantation for SONFH.

TMEM160 inhibits KEAP1 to suppress ferroptosis and induce chemoresistance in gastric cancer

Chemoresistance is the most significant challenge affecting the clinical efficacy of the treatment of patients with gastric cancer (GC). Here we reported that transmembrane protein 160 (TMEM160) suppressed ferroptosis and induced chemoresistance in GC cells. Mechanistically, TMEM160 recruited the E3 ligase TRIM37 to promote K48-linked ubiquitination and degradation of KEAP1, thereby activating NRF2 and transcriptionally upregulating the target genes GPX4 and SLC7A11 to inhibit ferroptosis. Further in vitro and in vivo experiments demonstrated that the combination of TMEM160 targeting and chemotherapy had a synergistic inhibitory effect on the growth of GC cells, which was partially NRF2-dependent. Moreover, TMEM160 and NRF2 protein levels were markedly overexpressed in GC tissues, and their co-overexpression was an independent factor for poor prognosis. Collectively, these findings indicate that TMEM160, as a pivotal negative regulator of ferroptosis, exerts a crucial influence on the chemoresistance of GC through the TRIM37-KEAP1/NRF2 axis, providing a potential new prognostic factor and combination therapy strategy for patients with GC.

The acidic microenvironment promotes pancreatic cancer progression via the lncRNA-LOC100507424/E2F1/FOXM1 axis

Pancreatic cancer is highly aggressive and sensitive to acidic microenvironments, which promote cancer cell survival and invasion. Long non-coding RNAs (lncRNAs) play crucial roles in cancer biology, helping cells adapt to microenvironmental changes, but their functions in the acidic microenvironment of pancreatic cancer are understudied. This study investigated the role of lncRNA LOC100507424 in pancreatic cancer, previously linked to glioma stem cells. Clinical specimens and cell line models cultured under acidic conditions showed that LOC100507424 was upregulated in pancreatic cancer tissues and further increased in acidic environments. Functional assays demonstrated that knockdown of LOC100507424 inhibited cell proliferation, invasion and metastasis. Mechanistically, LOC100507424 transcriptionally regulated FOXM1 expression through its interaction with E2F1. In vivo studies confirmed that LOC100507424 promoted tumor growth in nude mice. These findings highlight the significance of lncRNAs in the acidic microenvironment of pancreatic cancer and suggest potential therapeutic targets.

Acetylation suppresses breast cancer progression by sustaining CLYBL stability

BACKGROUND

The incidence of breast cancer remains high and it remains the leading cause of cancer-related deaths in women. A better understanding of the molecular mechanisms of breast cancer and identifying novel biomarkers will help improve therapeutic strategies. Citrate lyase beta like (CLYBL) is expressed at low levels in breast cancer tissues and is associated with low patient survival rates. In this study, we explored the regulatory mechanisms of CLYBL and its acetylation in breast cancer.

METHODS

CLYBL expression patterns in breast cancer were assessed using a breast cancer tissue microarray, immunohistochemistry, and publicly available datasets. The acetylation patterns of CLYBL and the related regulatory functions were detected by high resolution mass spectrometry, immunoprecipitation assays, and western blot analysis. The potential effects of CLYBL and its acetylation on breast cancer were determined using both in vitro and in vivo assays.

RESULTS

CLYBL was expressed at lower levels in breast cancer samples compared with normal tissues. This low CLYBL expression was associated with poor patient survival rates. Overexpressing CLYBL could inhibit breast cancer and reduce NRF2 pathway-mediated antioxidants. We identified two acetylated lysine sites in CLYBL, K57 and K82, using acetylated peptide affinity enrichment and high-resolution mass spectrometry. Our results suggest that K82 is the main acetylation site. Further work showed that the p300/CBP associated factor (PCAF) and histone deacetylase 3 (HDAC3) as the CLYBL acetyltransferase and deacetylase, respectively. Additionally, CLYBL acetylation facilitates its own protein stability by reducing it affinity for ubiquitin, thus enhancing the anti-breast cancer effects.

CONCLUSION

We revealed the role of CLYBL overexpression and its acetylation in breast cancer. Our study suggests that CLYBL is a potential molecular target for breast cancer therapy.

Oxidative stress at telomeres triggers internal DNA loops, TRF1 dissociation, and TRF2-dependent R-loops

Telomeres are the nucleoprotein structures at chromosome ends. Telomeres are particularly sensitive to oxidative stress, which can induce telomere damage, shortening, and premature cellular senescence. How oxidative damage influences telomere structure has not been defined. Here, we induce oxidative damage at telomeres using menadione, which damages mitochondria mimicking intrinsic oxidative stress. We find that oxidative stress induces at telomeres single-stranded DNA breaks, internal DNA loop structures, dissociation of the shelterin component TRF1, upregulation of TERRA long noncoding RNA, and increased DNA:RNA hybrid structures known as R-loops. R-loop formation is enhanced not only in cis at telomeres, which show increased TERRA transcription, but also in trans at telomeres at which TERRA transcription is not induced indicating post-transcriptional R-loop formation. Finally, we show that oxidative damage induced R-loop formation requires TRF2, whose R-loop promoting activity may be unleashed upon TRF1 dissociation from telomeres. Altogether, our findings uncover in response to oxidative stress major remodelling of telomeric DNA, RNA, and shelterin complexes, and they unravel a physiological role of TRF2's ability to stimulate TERRA R-loop formation. We propose that the identified structural changes may facilitate DNA damage signalling and repair pathways to maintain telomere integrity during development and aging.

Unspliced XBP1 enhences metabolic reprogramming in colorectal cancer cells by interfering with the mitochondrial localization of MGME1

Tumor cells undergo metabolic reprogramming, which makes them tend to utilize anaerobic glycolysis rather than oxidation to rapidly produce energy and intermediate products required for proliferation. In this process, mitochondria inevitably undergo corresponding alterations; however, the specific alterations in mitochondria across different cancer types and the mechanisms governing these changes remain poorly understood. This study demonstrated that unspliced X-box binding protein 1 (XBP1-u) inhibits the translocation of mitochondrial genome maintenance exonuclease 1 (MGME1) into mitochondria by binding to the mitochondrial targeting sequence (MTS) of MGME1. This interaction results in the accumulation of mitochondrial 7sDNA, a reduction in mitochondrial DNA copy number, and a decrease in mitochondrial abundance. Consequently, this shift enhances the production of glycolysis and pentose phosphate pathway intermediates, thereby promoting the proliferation of colorectal cancer (CRC) cells. Our findings elucidated the critical mechanism by which XBP1-u enhances metabolic reprogramming by modulating mitochondrial biogenesis, and uncovered a novel role of MGME1 in the progression of CRC.

Leveraging Vitamin C to Augment Nanoenabled Photothermal Immunotherapy

Photothermal immunotherapy (PTI) is valuable for precise tumor targeting and immune activation. However, its efficacy is hindered by insufficient immune response, elevated antioxidant levels within tumor, and intrinsic tumor resistance mechanisms. This study introduces Vitamin C (VC), a widely available dietary nutrient, as an effective enhancer for PTI. High-dose VC induces oxidative imbalance in tumor cells, making them more susceptible to nanoenabled near-infrared-II photothermal therapy (NIR-II PTT) with the photosensitizer IR1080. The combination of VC and NIR-II PTT significantly amplifies antitumor immunity by upregulating CXCL16 expression and promoting CXCR6+ T cell infiltration. Clinical data reveal that higher CXCL16 and CXCR6 levels in human tumors correlate with improved survival and T cell infiltration, underscoring the translational potential of this approach. This study positions VC as a safe, accessible, and cost-effective dietary enhancer for PTI, reshaping the role of dietary nutrients in cancer therapy and offering a strategy for overcoming treatment resistance.

The Assessment of the Effect of Autophagy Inhibitors-Chloroquine and 3-Methyladenine on the Antitumor Activity of Trametinib Against Amelanotic Melanoma Cells

Malignant melanoma, particularly amelanotic melanoma, contributes to a very serious problem in public health. One way to find new therapies is to learn about and understand the molecular pathways that regulate cancer growth and development. In the case of a tumor, the autophagy process can lead to the development or inhibition of cancer. This study aimed to assess the cytotoxicity of connection trametinib (MEK1 and MEK2 kinase inhibitor) with autophagy inhibitors-chloroquine (lysosomal clearance of autophagosomes inhibitor) and 3-methyladenine (phosphatidylinositol 3-kinases inhibitor), on two amelanotic melanoma cell lines (C32 and A-375). The results showed that combination therapy had better anti-proliferative effects than alone therapy in both cell lines. The C32 cell line was more sensitive to 3-methyladenine treatment (alone and in combinations), and the A375 line showed sensitivity to chloroquine and 3-methyladenine (alone and in combinations). The anti-proliferative effect was accompanied by dysregulation of the cell cycle, a decrease in the reduced thiols, the depolarization of the mitochondrial membrane and the level of p44/p42 MAPK. Both inhibitors have the ability to induce apoptosis. Differences in the level of LC3A/B and LC3B proteins between the chloroquine and the 3-methyladenine samples indicate that these drugs inhibit autophagy at different stages. The enhancement of the effect of trametinib by autophagy inhibitors suggests the possibility of combining drugs with anti-cancer potential with modulators of the autophagy process.

GCLC desuccinylation regulated by oxidative stress protects human cancer cells from ferroptosis

Tumor cells evolve strong antioxidant capacities to counteract the abnormal high level of reactive oxygen species (ROS) in the tumor microenvironment. Glutamate-cysteine ligase catalyzing subunit (GCLC) for synthesis of antioxidant glutathione (GSH) represents the key enzyme to maintain redox homeostasis of tumor cells, however, whether its activity is regulated by posttranslational modifications, such as succinylation, remains to be clarified. Here, we demonstrate the existence of succinylation modification on GCLC by in vitro and in vivo assays. NAD-dependent deacetylase Sirtuin-2 (SIRT2) serves as the desuccinylase and catalyzes GCLC desuccinylation at sites of K38, K126, and K326. Specifically, GCLC directly interacts with SIRT2, which can be substantially enhanced upon ROS treatment. This strengthened association results in GCLC desuccinylation and activation, consequently promoting GSH synthesis and rendering cancer cells resistant to ferroptosis induction. Depletion of SIRT2 decreases total GSH level and meanwhile increases the cellular susceptibility to ferroptosis, which can mostly be rescued by introducing wild-type GCLC, but not its 3K-E mutant. We further demonstrated that histone acetyltransferase P300 serves as the succinyltransferase of GCLC, and their association is remarkably decreased after ROS treatment. Thus, SIRT2-regulated GCLC succinylation represents an essential signaling axis for cancer cells to maintain their redox balance in coping with oxidative stress-induced ferroptosis.

Targeting B4GALT3 in BMSCs-EVs for Therapeutic Control of HCC via NF-κB pathway inhibition

Examining the communications in the tumor microenvironment (TME) specific to hepatocellular carcinoma (HCC), this exploration looks into the role played by beta-1,4-Galactosyltransferase III (B4GALT3) in bone marrow mesenchymal stromal cell-derived extracellular vesicles (BMSCs-EVs) regarding the NF-κB pathway and the triggering of cancer-associated fibroblasts (CAF). Through a multidisciplinary approach combining transcriptome sequencing, bioinformatic analysis, and various experimental models, the involvement of B4GALT3 in regulating CAF activity by modulating NF-κB signaling was brought to light in our study. The outcomes suggest that targeting B4GALT3 could impede HCC cell migration and invasion, promote apoptosis, and dampen tumor progression and metastasis, offering novel insights into potential therapeutic strategies for combating HCC.

Towards precision medicine using biochemically triggered cleavable conjugation

Personalised and precision medicines are emerging as the future of therapeutic strategies. Biochemically triggered cleavable conjugation is thus crucial and timely due to its potential to response as per the loco-regional environment. It enables targeted release of therapeutic agents in response to specific biochemical signals and thus minimizing off-target effects and improving treatment precision. It holds promise in a range of biomedical applications, including cancer therapy, senolytic therapy, gene therapy, and regenerative medicine. The focus of this review is to offer comprehensive insight into the significance of biochemically cleavable conjugations within intrinsically stimuli-responsive architectures. Pathological conditions and alteration in tissues microenvironment in the body exhibit distinct biochemical settings characterized by change in redox potential, pH level, hypoxia, reactive oxygen species (ROS), and various catalytic protein/enzyme overexpression. Understanding these intrinsic features is crucial for researchers aiming to develop intelligent cleavable bio-engineered systems for biomedicines. By strategically designing cleavable linkage, researchers can leverage the variations in the tumor, infection, inflammation, and senescence microenvironments. Through an extensive examination of relevant literature, we present a comprehensive classification of the intrinsic physicochemical differences found in pathological areas and their applications in drug delivery, prodrug activation, imaging, and theranostics for future personalised medicines. This review will provide comprehensive guidance and critical insights to researchers in both industry and academia who are involved in the design of advanced, functional biochemically cleavable conjugations.

Spatially targeted triple amplification of oxidative stress for enhanced tumor therapy via effective modulation of metal ion valence states

Inducing oxidative stress through metal ions activated biocatalysis is a fundamental mechanism of metal ion-interference therapy (MIIT). However, the actual catalytic efficiency of MIIT is often limited by the random valence states of metal ions and scattered space. Herein, copper-iron bimetallic sulfide nanoparticles coated with bovine serum albumin (CFS NPs) are synthesized through metal ion valence modulation strategy. Significant amounts of Cu⁺ and Fe²⁺ were released by CFS NPs, which is crucial for catalyzing Fenton-like reaction. The presence of Fe³⁺ further boosts Fe²⁺ availability and protects against hydroxyl radical (•OH) elimination via glutathione (GSH) consumption, amplifying the mitochondrial oxidative stress to induce apoptotic cell death. This oxidative stress damage is manifested in Cu+ targeting the mitochondrial tricarboxylic acid (TCA) cycle, further causing proteotoxic stress and cuproptosis. The production of lipid peroxidation (LPO) and the inactivation of glutathione peroxidase 4 (GPX4) expression are also affected by the amplified oxidative stress to achieve efficient ferroptosis. As a result, the synergistic apoptosis/cuproptosis/ferroptosis multimodal therapy almost completely inhibits tumor growth in vivo. It is believing that CFS NPs provide feasible implications for multiple combination therapy of tumors with the rational regulation of metal ion valence state and precise spatial control to effectively improve the level of oxidative stress. STATEMENT OF SIGNIFICANCE: : Metal ion-interference therapy induces oxidative stress in tumor cells via metal ion-activated biocatalysis, influencing reactive oxygen species (ROS) levels, proteotoxic stress, and lipid peroxidation accumulation. However, the actual catalytic efficiency of metal ion-interference therapy is often limited by the random valence state of these metal ions and scattered space. Herein, we constructed variable valence copper-iron bimetallic sulfides nanoparticles (CFS NPs) through metal ion valence modulation strategy to overcome the key factors that constrain efficiency with the combination of triple oxidative stress spatially treatment for apoptosis/cuproptosis/ferroptosis therapy. The reduced acidity and GSH concentration within normal cells lead to a much low cytotoxicity to normal cells, and therefore higher biocompatibility and biosafety for bio-medical applications.

The Role and Molecular Pathways of SIRT6 in Senescence and Age-related Diseases

SIRT6 is a NAD+-dependent histone deacetylase with crucial roles in controlling DNA damage repair, telomere homeostasis, oxidative stress, autophagy, and other cellular processes, and it has long been recognized as a longevity-associated protein. This review details its anti-aging-related mechanisms. First, SIRT6 facilitates DNA repair pathways and maintains genome stability by deacetylating histone H3 at K56, K9, and K18 residues, in addition to participating in DNA damage repair through mono-ADP-ribosylation and other mechanisms. Second, SIRT6 preserves telomere integrity and mitigates cellular senescence by reducing oxidative stress-induced damage through the regulation of reactive oxygen species (ROS), inhibition of inflammation, and other pathways. Furthermore, SIRT6 promotes autophagy, slowing cellular senescence via the modulation of various signaling pathways, including AMPK, IGF-Akt-mTOR, H133Y, IL-1β, and mitochondrial autophagy-related proteins. Finally, SIRT6 regulates multiple signaling pathways, such asNF-κB, FOXO, and AMPK, to counteract the aging process. This review particularly delves into the interplay between SIRT6 and various diseases, including tumors, cardiovascular diseases (e.g., atherosclerosis, heart failure), metabolic diseases (e.g., type 2 diabetes, dyslipidemia, gluconeogenesis, osteoporosis), and neurodegenerative diseases (e.g., Alzheimer's disease). Moreover, recent advancements in SIRT6-regulated compounds (e.g., C3G, BZBS, Fisetin, FNDC5, Lycorine hydrochloride, and Ergothioneine) are discussed as potential therapeutic agents for these mediated diseases.

Integrin β6/Annexin A2 axis triggers autophagy to orchestrate hepatocellular carcinoma radioresistance

Radiotherapy (RT) is one of the main therapies for hepatocellular carcinoma (HCC), but its effectiveness has been constrained due to the resistance effect of radiation. Thus, the factors involved in radioresistance are evaluated and the underlying molecular mechanisms are also done. In this present study, we identified Integrin β6 (ITGB6) as a potential radioresistant gene through an integrative analysis of transcriptomic profiles, proteome datasets and survival using HCC cases treated with IR. We show that ITGB6 functionally contributed to radioresistance by activating autophagy through a series of in vitro and in vivo methods, such as clonogenic assays, autophagy flux (LC3B-GFP-mCherry reporter) analysis and a subcutaneous transplantation model. Mechanically, ITGB6 binds to Annexin A2 (ANXA2) and enhanced its stability by competitively antagonizing proteasome mediated ANXA2 degradation, thereby promoting autophagy and radioresistance. Notably, HCC radioresistance was significantly improved by either blocking ITGB6 or autophagy, but the combination was more effective. Importantly, ITGB6/ANXA2 axis triggered autophagic program endowed HCC cells with radioresistant activity in a radiated patient-derived xenograft (PDX) model and hydrodynamic injection in liver-specific Itgb6-knockout mice, further supported by clinical evidence. Together, our data revealed that ITGB6 is a radioresistant gene stabilizing the autophagy regulatory protein ANXA2, providing insights into the biological and potentially clinical significance of ITGB6/ANXA2 axis in radiotherapy planning of HCC.

RNF7-Mediated ROS Targets Malignant Phenotype and Radiotherapy Sensitivity in Glioma With Different IDH1 Genotypes

RNF7 (Ring Finger Protein 7) is a key component of CRLs (Cullin-RING-type E3 ubiquitin ligases) and has been found to possess intrinsic anti-ROS capabilities. Aberrant expression of RNF7 has been observed in various tumor types and is known to significantly influence tumor initiation and progression. However, the specific role of RNF7 in glioblastoma remains unclear. IDH (isocitrate dehydrogenase) mutations, which induce metabolic reprogramming and result in notable heterogeneity among glioma with different IDH genotypes. Through analysis of public glioma databases, we identified a high expression of RNF7 in glioma and its correlation with patient prognosis. Moreover, we observed variations in RNF7 expression and its association with patient outcomes under different treatment modalities among different IDH genotypes. In this study, we demonstrated the critical role of RNF7 in the malignant phenotype of IDH1-mutant glioma and its contribution to radiation resistance. Subsequent functional enrichment analysis of RNF7 in glioma, coupled with validation through cellular experiments, confirmed its significant involvement in maintaining redox balance. Our findings suggest that RNF7 exerts a buffering effect against radiation-induced oxidative stress and counterbalances the redox stress induced by IDH1 mutation through its anti-ROS activity. Additionally, our follow-up investigations revealed that the upregulation of RNF7 after radiation exposure and in IDH1-mutant glioma cells is induced by ROS. Collectively, our study underscores the potential of RNF7 as a molecular biomarker in glioma. Elevated RNF7 expression often indicates a heightened metabolic resilience in glioma, leading to resistance against radiotherapy.

Timosaponin AIII Enhances Radiosensitivity in Breast Cancer through Induction of ROS-Mediated DNA Damage and Apoptosis

Breast cancer is a commonly diagnosed cancer, while resistance to radiation therapy remains an important factor hindering the treatment of patients. Timosaponin AIII (Tim AIII) is a steroidal saponin from the Anemarrhena asphodeloides. Its pharmacologic effects and mechanisms for enhancing radiotherapy remain largely unknown. This study investigates Tim AIII and aims to unravel the underlying mechanisms. Experiments, including cell cloning, scratch assays, cell cycle, apoptosis assays, immunofluorescence staining, and reactive oxygen species (ROS) assessments, were conducted on breast cancer cell lines MDA-MB-231 and JIMT-1 to investigate the impact of Tim AIII combined with radiation. Western blot analyses were used to detect γ-H2AX expression, ROS-related pathways, ATM-CHK2, and AKT-MTOR pathways. Subcutaneous tumor experiments in nude mice confirmed in vivo radiation sensitization. When combined with radiation, Tim AIII significantly inhibited cell clone formation, impeded cancer cell migration, increased G2/M phase arrest and apoptosis. Immunofluorescence showed prolonged γ-H2AX signals. Molecular investigations indicated Tim AIII amplified radiation-induced ROS production, inducing ROS-mediated DNA damage and apoptosis. It activated ATM-CHK2 while inhibiting the AKT-MTOR pathway. Tim AIII enhances radiation sensitivity in breast cancer cells, both in vitro and in vivo. Through ROS-mediated DNA damage and apoptosis, activation of ATM/Chk2 and inhibition of the AKT-MTOR pathway induce G2/M phase arrest, ultimately boosting radiation sensitivity via the mitochondrial-mediated apoptotic pathway.

Pharmacological Inhibition of TXNRD1 by a Small Molecule Flavonoid Butein Overcomes Cisplatin Resistance in Lung Cancer Cells

Mammalian cytosolic selenoprotein thioredoxin reductase (TXNRD1) is crucial for maintaining the reduced state of cellular thioredoxin 1 (TXN1) and is commonly up-regulated in cancer cells. TXNRD1 has been identified as an effective target in cancer chemotherapy. Discovering novel TXNRD1 inhibitors and elucidating the cellular effects of TXNRD1 inhibition are valuable for developing targeted therapies based on redox regulation strategies. In this study, we demonstrated that butein, a plant-derived small molecule flavonoid, is a novel TXNRD1 inhibitor. We found that butein irreversibly inhibited recombinant TXNRD1 activity in a time-dependent manner. Using TXNRD1 mutant variants and LC-MS, we identified that butein modifies the catalytic cysteine (Cys) residues of TXNRD1. In cellular contexts, butein promoted the accumulation of reactive oxygen species (ROS) and exhibited cytotoxic effects in HeLa cells. Notably, we found that pharmacological inhibition of TXNRD1 by butein overcame the cisplatin resistance of A549 cisplatin-resistant cells, accompanied by increased cellular ROS levels and enhanced expression of p53. Taken together, the results of this study demonstrate that butein is an effective small molecule inhibitor of TXNRD1, highlighting the therapeutic potential of inhibiting TXNRD1 in platinum-resistant cancer cells.

Patenting perspective on Keap1 inhibitors (2019-2024)

INTRODUCTION

Kelch-like ECH-associated protein 1 (Keap1), an E3 ligase negatively regulating the nuclear factor erythroid 2-related factor 2 (Nrf2), has emerged as an auspicious drug target for treating ailments associated with oxidative stress and inflammation. Discovery of Keap1 inhibitors have attracted significant interest.

AREAS COVERED

This review covers patents on Keap1 inhibitors from 2019 to 2024, providing a comprehensive analysis of their structural characteristics, optimization strategies, pharmacological properties and clinical progress.

EXPERT OPINION

Extensive efforts have been devoted to enhance potency and drug-like properties of Keap1 inhibitors. Strategies such as ROS-cleavable prodrug design, bivalent inhibition and PROTACs are emerging. As the range of drug types and applications expands, Keap1 inhibitors are becoming a sagacious option for disease treating.

PepGAT, a chitinase-derived peptide, alters the proteomic profile of colorectal cancer cells and perturbs pathways involved in cancer survival

Colorectal cancer (CRC) affects the population worldwide, occupying the first place in terms of death and incidence. Synthetic peptides (SPs) emerged as alternative molecules due to their activity and low toxicity. Proteomic analysis of PepGAT-treated HCT-116 cells revealed a decreased abundance of proteins involved in ROS metabolism and energetic metabolisms, cell cycle, DNA repair, migration, invasion, cancer aggressiveness, and proteins involved in resistance to 5-FU. PepGAT induced earlier ROS and apoptosis in HCT-116 cells, cell cycle arrest, and inhibited HCT-116 migration. PepGAT enhances the action of 5-FU against HCT-116 cells by dropping down 6-fold the 5-FU toward HCT-116 and reduces its toxicity for non-cancerous cells. These findings strongly suggest the multiple mechanisms of action displayed by PepGAT against CRC cells and its potential to either be studied alone or in combination with 5-FU to develop new studies against CRC and might develop new drugs against it.

Roles of selenium-containing glutathione peroxidases and thioredoxin reductases in the regulation of processes associated with glioblastoma progression

Glioblastoma remains the most common and aggressive primary tumor of the central nervous system in adults. Current treatment options include standard surgical resection combined with radiation/chemotherapy, but such protocol most likely only delays the inevitable. Therefore, the problem of finding therapeutic targets to prevent the occurrence and development of this severe oncological disease is currently acute. It is known that the functions of selenoproteins in the regulation of carcinogenesis processes are not unambiguous. Either they exhibit cytotoxic activity on cancer cells, or cytoprotective. A special place in the progression of oncological diseases of various etiologies is occupied by proteins of the thioredoxin and glutathione systems. These are two cellular antioxidant systems that regulate redox homeostasis, counteracting the increased production of reactive oxygen species in cells. The review reflects the latest data on the role of key enzymes of these redox systems in the regulation of processes associated with the progression of glioblastoma. A thorough consideration of these issues will expand fundamental knowledge about the functions of selenium-containing thioredoxin reductases and glutathione peroxidases in the therapy of glioblastomas and provide an understanding of the prospects for the treatment of this aggressive oncological disease.

Transketolase promotes osteosarcoma progression through the YY1-PAK4 axis

Osteosarcoma, a malignant bone tumor that occurs in adolescents, proliferates and is prone to pulmonary metastasis. Osteosarcoma is characterized by high genotypic heterogeneity, making it difficult to identify reliable anti-osteosarcoma targets. The genotype of osteosarcoma may be highly dynamic, but its high dependence on energy remains constant. Fortunately, tumors tend to have relatively consistent metabolic types. Targeting metabolism with anti-tumor therapies is a new strategy for treating tumors. Genes related to carbohydrate metabolism are widely and highly expressed in tumor tissues. Transketolase (TKT), a key enzyme at the non-oxidative stage of the pentose phosphate pathway, is up-regulated in various tumors. In the present study, TKT promoted osteosarcoma cell proliferation non-metabolically. Specifically, TKT bound directly to amino acid residues of Yin Yang 1 (YY1) at amino acids 201-228, stimulating YY1 to bind to the promoter of P21 activated kinase 4 (PAK4) and resulting in PAK4 expression and activation of the phosphoinositide 3-kinase-Akt signaling pathway. Additionally, we designed a peptide, YY1-PEP, based on the exact mechanism of how TKT promotes osteosarcoma. Per in vivo and in vitro experiments, YY1-PEP displayed anti-osteosarcoma properties. The present study provides a new feasible strategy against osteosarcoma progression.

Dying to survive: harnessing inflammatory cell death for better immunotherapy

Immunotherapy has transformed cancer treatment paradigms, but its effectiveness depends largely on the immunogenicity of the tumor. Unfortunately, the high resemblance of cancer to normal tissues makes most tumors immunologically 'cold', with a poor response to immunotherapy. Danger signals are critical for breaking immune tolerance and mobilizing robust, long-lasting antitumor immunity. Recent studies have identified inflammatory cell death modalities and their power in providing danger signals to trigger optimal tumor suppression. However, key mediators of inflammatory cell death are preferentially silenced during early tumor immunoediting. Strategies to rejuvenate inflammatory cell death hold great promise for broadening immunotherapy-responsive tumors. In this review, we examine how inflammatory cell death enhances tumor immunogenicity, how it is suppressed during immunoediting, and the potential of harnessing it for improved immunotherapy.

New insights into reductive stress responses and its clinical relation in cancer

Cells are susceptible to both oxidative and reductive stresses, with reductive stress being less studied and potentially therapeutic in cancer. Reductive stress, characterized by an excess of reducing equivalents exceeding the activity of endogenous oxidoreductases, can lead to an imbalance in homeostasis, causing an increase in reactive oxygen species induction, affecting cellular antioxidant load and flux. Unlike oxidative stress, reductive stress has been understudied and poorly understood, and there is still much to learn about its mechanisms in cancer, its therapeutic potential, and how cancer cells react to it. Changes in redox balance and interference with redox signaling are linked to cancer cell growth, metastasis, and resistance to chemotherapy and radiation. Overconsumption of reducing equivalents can reduce metabolism, alter protein disulfide bond formation, disrupt mitochondrial homeostasis, and disrupt cancer cell signaling pathways. Novel approaches to delivering or using cancer medicines and techniques to influence redox biology have been discovered. Under reductive stress, cancer cells may coordinate separate pools of redox pairs, potentially impacting biology.

Harnessing Nanoreactors with Coupled Optical and Molecular Modalities for Photoenzymatic Modulation of Active Species in Cancer Photo-Immunotherapy

The dynamic process in tumor ablation requires both the generation of reactive oxygen species (ROS) to elicit immunogenic cell death (ICD) and the subsequent reduction of ROS levels to maintain the stimulatory activity of signaling proteins and recover T cells' immune function. Inspired by the regulation mechanism of redox homeostasis in myeloid-derived suppressor cells and the high-selectivity in alcohols/aldehydes conversions of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and Fe(III) synergistic catalysis, photoenzymatic modulators with contradictory but synergistic functions are developed for adaptive photo-immunotherapy of cancer. In particular, poly(caffeic acid) (PCA) nanospheres are synthesized by highly efficient oxidative polymerization of CA. The obtained π-conjugated structures have an extended absorbance in the near-infrared (NIR) region, narrow band energy (0.86 eV), and low exciton binding energy (43.56 meV) that lead to polymerization-enhanced type I photosensitization and photostability. Meanwhile, abundant semiquinone radicals existing in PCA bestow them with superior antioxidant function. Under NIR irradiation, the elevated superoxide radical yields (3.5-fold compared with CA) and heat stress elicit robust ICD. When irradiation ceases, active species downregulation and the infiltration of T lymphocytes increase by 2.7-fold compared with conventional photosensitizers. As envisaged, this work demonstrates a novel tactic to remodel redox and immune homeostasis for effective inhibition of tumor growth and metastasis.

Nuclear translocation of the LINE-1 encoded ORF1 protein alters nuclear envelope integrity in human neurons

LINE-1 retrotransposons are increasingly implicated in aging and neurodegenerative diseases, yet the precise pathogenic mechanisms remain elusive. While the endonuclease and reverse transcriptase activities of LINE-1-encoded ORF2p can induce DNA damage and inflammation, a role of LINE-1 ORF1p in cellular dysfunctions stays unassigned. Here we demonstrate, using a neuronal cellular model, that ORF1p translocates into the nucleus upon arsenite-induced stress, directly interacting with nuclear import (KPNB1), nuclear pore complex (NUP153), and nuclear lamina (Lamin B1) proteins. Nuclear translocation of ORF1p disrupts nuclear integrity, nucleocytoplasmic transport, and heterochromatin structure, features linked to neurodegeneration and aging. Elevated nuclear ORF1p levels induced either by arsenite-induced stress, ORF1p overexpression, or as observed in Parkinson's disease post-mortem brain tissues correlate with impaired nuclear envelope (NE) morphology. Stress-induced nuclear alterations are mitigated by blocking ORF1p nuclear import or with the anti-aging drug remodelin. This study thus reveals a pathogenic action of nuclear ORF1p in human neurons driving NE alterations and thereby contributing to LINE-1-mediated cell toxicity.

Single-nucleus multiomic analysis of Beckwith-Wiedemann syndrome liver reveals PPARA signaling enrichment and metabolic dysfunction

Beckwith-Wiedemann Syndrome (BWS) is an epigenetic overgrowth syndrome caused by methylation changes in the human 11p15 chromosomal locus. Patients with BWS may exhibit hepatomegaly, as well as an increased risk of hepatoblastoma. To understand the impact of these 11p15 changes in the liver, we performed a multiomic study [single nucleus RNA-sequencing (snRNA-seq) + single nucleus assay for transposable-accessible chromatin-sequencing (snATAC-seq)] of both BWS-liver and nonBWS-liver tumor-adjacent tissue. Our approach uncovers hepatocyte-specific enrichment of processes related to peroxisome proliferator-activated receptor alpha (PPARA). To confirm our findings, we differentiated a BWS induced pluripotent stem cell model into hepatocytes. Our data demonstrate the dysregulation of lipid metabolism in BWS-liver, which coincides with observed upregulation of PPARA during hepatocyte differentiation. BWS hepatocytes also exhibit decreased neutral lipids and increased fatty acid β-oxidation. We also observe increased reactive oxygen species byproducts in BWS hepatocytes, coinciding with increased oxidative DNA damage. This study proposes a putative mechanism for overgrowth and cancer predisposition in BWS liver due to perturbed metabolism.

Dnmt3a-mediated hypermethylation of FoxO3 promotes redox imbalance during osteoclastogenesis

Redox imbalance contributes to aberrant osteoclastogenesis and osteoporotic bone loss. In this study, we observed lower Forkhead box protein O3 (FoxO3), a transcription factor associated with cellular oxidative stress, enhanced osteoclastogenesis in osteoporosis (OP). Single-cell RNA sequencing (scRNA-seq) analysis on the human femoral head indicated that FoxO3 is widely expressed in macrophages. Furthermore, Lysm-Cre;FoxO3f/f OVX mice showed increased reactive oxygen species (ROS), enhanced osteoclastogenesis, and more bone loss than normal OVX mice. Mechanistically, we identified FoxO3 promoter methylation as a crucial factor contributing to decreased FoxO3, thereby influencing osteoclastogenesis and OC function. Intriguingly, we observed that Dnmt3a, highly expressed during osteoclastogenesis, played a pivotal role in regulating the methylation of the FoxO3 promoter. Knockdown of Dnmt3a promoted FoxO3 expression, inhibiting osteoclastogenesis and mitigating OP. Interestingly, we observed that Dnmt3a alleviated osteoclastogenesis by suppressing ROS via upregulating FoxO3 rather than inducing the dissociation of RANK and TRAF6. Collectively, this study elucidates the role and mechanism of FoxO3 in osteoclastogenesis and OP, providing a epigenetic target for the treatment of OP.

The clinical-grade CBP/ p300 inhibitor CCS1477 represses the global NRF2-dependent cytoprotective transcription program and re-sensitizes cancer cells to chemotherapeutic drugs

Constitutive activation of NRF2 provides a selective advantage to malignant tumour clones through the hijacking of the NRF2-dependent cytoprotective transcriptional program, which allows the cancer cells to survive and thrive in the chemically stressful tumour niche, whilst also providing resistance to anti-cancer drugs due to the upregulation of xenobiotic metabolizing enzymes and drug efflux pumps. Through a small-molecule epigenetic screen carried out in KEAP1 mutant lung cancer cells, in this study, we identified CCS1477 (Inobrodib) to be an inhibitor of the global NRF2-dependent transcription program. Mechanistically, CCS1477 is able to repress NRF2's cytoprotective response through the inhibition of its obligate transcriptional activator partner CBP/p300. Importantly, in addition to repressing NRF2-dependent anti-oxidative stress and xenobiotic metabolizing enzyme gene expression, CCS1477 treatment is also able to reverse the chemoresistance phenotype and re-sensitize NRF2-activated tumour cells to anti-cancer drugs. Furthermore, in co-culture experiments of KEAP1 mutant cancer cells with primary human T cells, CCS1477 treatment suppressed the acquisition of the T cell exhaustion transcriptional state, which should function to augment the anti-cancer immune response. Thus, CCS1477-mediated inhibition of CBP/p300 represents a novel therapeutic strategy with which to target the currently untreatable tumours with aberrant NRF2 activation.

Chronic Inflammation to Cancer: The Impact of Oxidative Stress on DNA Methylation

The genomic landscape of cancer cells is complex and heterogeneous, with aberrant DNA methylation being a common observation. Growing evidence indicates that oxidants produced from immune cells may interact with epigenetic processes, and this may represent a mechanism for the initiation of altered epigenetic patterns observed in both precancerous and cancerous cells. Around 20% of cancers are linked to chronic inflammatory conditions, yet the precise mechanisms connecting inflammation with cancer progression remain unclear. During chronic inflammation, immune cells release oxidants in response to stimuli, which, in high concentrations, can cause cytotoxic effects. Oxidants are known to damage DNA and proteins and disrupt normal signalling pathways, potentially initiating a sequence of events that drives carcinogenesis. While research on the impact of immune cell-derived oxidants on DNA methylation remains limited, this mechanism may represent a crucial link between chronic inflammation and cancer development. This review examines current evidence on inflammation-associated DNA methylation changes in cancers related to chronic inflammation.

Mitochondrial fatty acid oxidation as the target for blocking therapy-resistance and inhibiting tumor recurrence: The proof-of-principle model demonstrated for ovarian cancer cells

INTRODUCTION

Cancer patients treated with current chemotherapeutic and targeted therapies frequently achieve partial remission, which ultimately relapse with more aggressive, drug-resistant tumor phenotypes. To a certain extent, drug-tolerant persister (DTP) cells are responsible for residual tumors after systemic anticancer therapy and the onset of acquired drug resistance. Therefore, novel therapies targeting DTP cells to prevent drug resistance and tumor recurrence are urgently needed.

OBJECTIVES

We aimed to investigate the traits and key vulnerabilities of drug-tolerant ovarian cancer persister cells and to seek out potential therapeutic strategies.

METHODS

We constructed paclitaxel-tolerant ovarian cancer persister cells by exposing ovarian cancer parental cells to a lethal dose of paclitaxel. Proteomics analysis, in vitro and in vivo assays were performed to identify biological processes that could serve as potential vulnerabilities in persister cells.

RESULTS

Paclitaxel-tolerant ovarian cancer persister cells were found to undergo a metabolic reprogramming through the upregulation of fatty acid oxidation (FAO). Treatment with the FAO inhibitor ST1326 suppressed FAO and increased sensitivity to paclitaxel in persister cells. Moreover, combination therapy with paclitaxel and ST1326 prevented ovarian tumor recurrence with satisfactory biosafety in a mouse model of ovarian cancer relapse, indicating that FAO disruption can improve the efficacy of paclitaxel-based therapy in ovarian cancer. Mechanistically, we found that paclitaxel treatment upregulated CEBPB, a transcription factor that induced the expression of the FAO-related enzyme HADHA and contributed to FAO elevation in persister cells.

CONCLUSIONS

This study revealed an upregulation of FAO in paclitaxel-tolerant ovarian cancer persister cells and provided a prospective paclitaxel-ST1326 combination therapy targeting persister cells that may prevent the development of acquired drug resistance and achieve superior long-term ovarian cancer control in the future. Our research established a conceptual framework for advancing personalized treatment approaches and enhancing patient outcomes in ovarian cancer therapy.

Plasma-activated saline hyperthermic perfusion-induced pyroptosis boosts peritoneal carcinomatosis immunotherapy

Peritoneal carcinomatosis (PC) is a common metastatic cancer with limited treatment options. Herein, we present a novel strategy for the combined treatment of PC involving plasma-activated saline (PAS) and hyperthermic intraperitoneal perfusion. PAS revealed a strong cytotoxic effect because of reactive oxygen species (ROS) in two-dimensional cultures and three-dimensional tumor spheroids of PC-related cell lines. Notably, PAS induced Gasdermin E (GSDME)-dependent pyroptosis and immunogenic cell death in vitro. PAS-enhanced hyperthermic intraperitoneal perfusion (PE-HIP) increased the number of CD3+, CD4+ and CD8+ T cells, while decreased the number of regulatory T cells, indicating that PAS stimulated T cell-based immune responses in vivo. Moreover, PE-HIP significantly inhibited tumor growth and improved survival in a PC-mice model, with no significant toxic side effects. Meanwhile, vaccination with PAS-induced cell pyroptosis activated systemic antitumor immunity to prevent subcutaneous tumor growth. Overall, PE-HIP can serve as a new approach for PC treatment by ROS-assisted cancer immunotherapy.

The Osgin Gene Family: Underexplored Yet Essential Mediators of Oxidative Stress

The Osgin gene family consists of two members, Osgin1 and Osgin2, involved in the cellular oxidative stress response. While many members of this essential cellular pathway have been extensively characterized, the Osgin gene family, despite its broad phylogenetic distribution, has received far less attention. Here, we review published articles and open-source databases to synthesize the current research on the evolutionary history, structure, biochemical and physiological functions, expression patterns, and role in disease of the Osgin gene family. Although Osgin displays broad spatiotemporal expression during development and adulthood, there is ambiguity regarding the cellular functions of the OSGIN proteins. A recent study identified OSGIN-1 as a flavin-dependent monooxygenase, but the biochemical role of OSGIN-2 has not yet been defined. Moreover, while the Osgin genes are implicated as mediators of cell proliferation, apoptosis, and autophagy, these functions have not been connected to the enzymatic classification of OSGIN. Misregulation of Osgin expression has long been associated with various disease states, yet recent analyses highlight the mechanistic role of OSGIN in pathogenesis and disease progression, underscoring the therapeutic potential of targeting OSGIN. In light of these findings, we suggest further avenues of research to advance our understanding of this essential, yet underexplored, gene family.

The rheumatoid arthritis drug Auranofin targets peroxiredoxin 1 and peroxiredoxin 2 to trigger ROS-endoplasmic reticulum stress axis-mediated cell death and cytoprotective autophagy

Auranofin (AF) is a gold-based compound and it has been used in the treatment of rheumatoid arthritis for over four decades. Recently, it has been demonstrated to show significant antitumor activity across various cancer types and is being repurposed as an anticancer drug. However, the precise mechanisms underlying its antitumor effects, particularly its binding targets, remain poorly understood. Here, we demonstrate that Auranofin (AF) exerts cytotoxic effects in 786-O renal cancer cells via inducing apoptosis. Mechanistic studies reveal that AF induces reactive oxygen species (ROS) accumulation, which is a key factor in mediating AF-induced stress and subsequently apoptosis. Notably, both ROS and ER stress induce autophagy, and inhibition of autophagy further enhances AF-induced cytotoxicity. Interestingly, activity-based protein profiling (ABPP) analysis identifies two key antioxidant enzymes, peroxiredoxin 1 (PRDX1) and peroxiredoxin 2 (PRDX2), as direct binding targets of AF. Importantly, overexpression of PRDX1 or PRDX2 inhibits AF-induced ROS accumulation and subsequent apoptosis. Overall, our findings demonstrate that AF induces apoptosis by covalently binding to PRDX1/2 to inhibit its activity, leading to ROS accumulation, which triggers ER stress and apoptosis. At the same time, ER stress triggers a cytoprotective autophagic response. These findings provide novel insights into the mechanism of AF-induced cytotoxicity and suggest PRDX1/2 as critical targets for the development of anti-renal cancer therapies.

Oxygen/sulfate radicals-generating CaS2O8 nanosonosensitizers induce PANoptosis and calcium overload for enhanced peritoneal metastasis immunotherapy

Peritoneal metastasis (PM) is typically intractable by immunotherapy due to an immunosuppressive microenvironment and the peritoneal-plasma barrier. Sonodynamic therapy (SDT) presents unique advantages of noninvasive in situ treatment and the potential for antitumor immune activation. Building upon SDT technology, the study reports on a novel biodegradable sonosensitizer, CaS2O8, characterized by a narrow bandgap, abundant oxygen vacancies and a rapid ultrasound (US) response for abdominal SDT. Such sonosensitizer only produces lethal reactive oxygen species (ROS) after US irradiation, which is nontoxic in a physiological environment. After US irradiation, CaS2O8 yields a large amount of sulfate radical (SO4-), as well as sonodynamic related ROS (OH, and 1O2), which exerts a synergistic effect with Ca2+ overload to induce Z-conformation nucleic acid by augmenting oxidative damage. As a result, the PANoptosis is initiated through the ZBP1/RIPK3 pathway in tumor cells. This inflammatory cell death leads to a multi-faceted release of tumor cell contents which serve as an in situ tumor antigen to induce a robust antitumor immune response. Notably, the precision sono-immunotherapy enhances the infiltration of T cells into tumors by transforming an immunosuppressive phenotype into an immunostimulatory one. Therefore, targeting PANoptosis by CaS2O8-induced SDT can provide an alternative or additional clinical treatment and prolonged survival outcome for patients with PM.

Folate-targeted nanoparticles for glutamine metabolism inhibition enhance anti-tumor immunity and suppress tumor growth in ovarian cancer

Ovarian cancer (OC) is a highly malignant gynecological tumor, and its effective treatment is frequently impeded by drug resistance and recurrent tumor growth. The reprogramming of glutamine metabolism in ovarian cancer is closely associated with tumor progression and the immunosuppressive tumor microenvironment. Recently, targeting metabolic reprogramming has emerged as a promising approach for cancer therapy. However, the application of such therapies is often constrained by their significant toxicity to normal tissues. In this study, we fabricated folate-targeted nanoparticles (FA-DCNPs) that co-encapsulate the glutamine metabolism inhibitor 6-diazo-5-oxo-L-norleucine (DON) and calcium carbonate (CaCO3). These nanoparticles alleviate damage to normal tissues by specifically targeting tumor cells via folate receptors (FOLR) mediation. Under acidic conditions, the FA-DCNPs release DON and Ca2+, generating a synergistic anti-tumor effect by impeding glutamine metabolism and inducing calcium overload. Additionally, FA-DCNPs target M2 phenotype tumor-associated macrophages (TAMs) via FOLR2, attenuating M2-TAMs activity. When partially phagocytosed by M0-TAMs, the nanoparticles restrict glutamate production, inhibiting polarization towards the M2 phenotype. This resulted in an increased proportion of M1-TAMs, thereby improving the tumor immune microenvironment. Our study explores a nanotherapeutic strategy that enhances the biosafety of anti-glutamine metabolism therapy through folate targeting, effectively suppresses tumor cell proliferation, and enhances the anti-tumor immune response.

Redox regulation: mechanisms, biology and therapeutic targets in diseases

Redox signaling acts as a critical mediator in the dynamic interactions between organisms and their external environment, profoundly influencing both the onset and progression of various diseases. Under physiological conditions, oxidative free radicals generated by the mitochondrial oxidative respiratory chain, endoplasmic reticulum, and NADPH oxidases can be effectively neutralized by NRF2-mediated antioxidant responses. These responses elevate the synthesis of superoxide dismutase (SOD), catalase, as well as key molecules like nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH), thereby maintaining cellular redox homeostasis. Disruption of this finely tuned equilibrium is closely linked to the pathogenesis of a wide range of diseases. Recent advances have broadened our understanding of the molecular mechanisms underpinning this dysregulation, highlighting the pivotal roles of genomic instability, epigenetic modifications, protein degradation, and metabolic reprogramming. These findings provide a foundation for exploring redox regulation as a mechanistic basis for improving therapeutic strategies. While antioxidant-based therapies have shown early promise in conditions where oxidative stress plays a primary pathological role, their efficacy in diseases characterized by complex, multifactorial etiologies remains controversial. A deeper, context-specific understanding of redox signaling, particularly the roles of redox-sensitive proteins, is critical for designing targeted therapies aimed at re-establishing redox balance. Emerging small molecule inhibitors that target specific cysteine residues in redox-sensitive proteins have demonstrated promising preclinical outcomes, setting the stage for forthcoming clinical trials. In this review, we summarize our current understanding of the intricate relationship between oxidative stress and disease pathogenesis and also discuss how these insights can be leveraged to optimize therapeutic strategies in clinical practice.

Thirty years of NRF2: advances and therapeutic challenges

Over the last 30 years, NRF2 has evolved from being recognized as a transcription factor primarily involved in redox balance and detoxification to a well-appreciated master regulator of cellular proteostasis, metabolism and iron homeostasis. NRF2 plays a pivotal role in diverse pathologies, including cancer, and metabolic, inflammatory and neurodegenerative disorders. It exhibits a Janus-faced duality, safeguarding cellular integrity in normal cells against environmental insults to prevent disease onset, whereas in certain cancers, constitutively elevated NRF2 levels provide a tumour survival advantage, promoting progression, therapy resistance and metastasis. Advances in understanding the mechanistic regulation of NRF2 and its roles in human pathology have propelled the investigation of NRF2-targeted therapeutic strategies. This Review dissects the mechanistic intricacies of NRF2 signalling, its cross-talk with biological processes and its far-reaching implications for health and disease, highlighting key discoveries that have shaped innovative therapeutic approaches targeting NRF2.