Mitochondrial metabolism-mediated redox regulation in cancer progression

Peptide-based nanoassembly enhances ferroptosis in cancer to overcome paclitaxel resistance

The development of chemotherapy resistance poses a major challenge in cancer therapy. Ferroptosis, a unique type of cell death, offers a promising strategy to combat this resistance. Herein, a peptide-based nanoassembly (PTX@CPG) consisting of paclitaxel (PTX), chlorin e6 (Ce6), and FFVLKPLGLAGK-(PEG8)3 was constructed to promote ferroptosis through reactive oxygen species (ROS) accumulation and overcome chemoresistance. Specifically, the small-sized PTX@CPG nanoparticles effectively penetrate tumors, where the microenvironment-responsive peptide is selectively cleaved by the high expression of matrix metalloproteinase 2. This process facilitates the targeted release of PTX and its reassembly into nanofibers, improving the tumor retention of Ce6 and enhancing its cellular uptake. The synergistic therapeutic effects of PTX in combination with photodynamic therapy on triple-negative breast cancer cells were validated through both in vitro and in vivo experiments. Impressively, upon laser irradiation, PTX@CPG significantly increased ROS production, thereby amplifying the ferroptosis-inducing effects of PTX. Moreover, ferroptosis triggered by PTX@CPG with laser reduced the levels of P-glycoprotein and glutathione peroxidase 4, contributing to the alleviation of chemoresistance. Overall, PTX@CPG with laser demonstrated effective spatial targeting and drug retention, enhancing ferroptosis through ROS accumulation and showcasing a promising approach for overcoming chemotherapy resistance in cancer therapy.

Revealing the role of bisphenol A on prostate cancer progression and identifying potential targets: A comprehensive analysis from population cohort to molecular mechanism

Bisphenol A (BPA) is a widespread environmental pollutant whose exact effects on prostate cancer (PCa) progression remain understudied. This study aims to investigate the effect and underlying molecular mechanisms between BPA exposure and PCa in a comprehensive approach. The multicenter cohort study found that BPA exposure plays an important role in promoting biochemical recurrence and death of PCa. BPA exposure significantly promoted PCa progression in both the animal model and in vitro experiments. RNA sequencing revealed a disruption of mitochondrial energy homeostasis in BPA-treated cells. In multiple datasets, 17 prognostic genes such as PFKFB4 were obtained to construct and verify a mitochondrial energy metabolism Score system. Based on network toxicology methods and transcriptome sequencing data, ESR1 was identified as a potential transcription factor targeting glycolytic enzyme PFKFB4 under BPA exposure. With the support of lncRNA and circRNA sequencing data, a molecular regulatory network of BPA promoting prostate cancer through mitochondrial energy metabolism reprogramming was constructed. Further molecular docking revealed that BPA has higher binding free energy to ERα than its natural ligand estradiol. Given the widespread presence of BPA in the environment, minimizing exposure to this chemical could represent a feasible approach in improving clinical outcomes.

The causal relationships between mitochondria and six types of cancer: a Mendelian randomization study

BACKGROUND

Mitochondria play a multifaceted role in tumorigenesis, influencing energy metabolism, redox balance, and apoptosis. However, whether mitochondrial traits causally affect cancer risk remains unclear. This study aimed to evaluate the potential causal effects of 82 mitochondrial-related exposures on six major cancers-hepatic, colorectal, lung, esophageal, thyroid, and breast-using Mendelian randomization (MR).

METHODS

Two-sample MR analysis was performed using the inverse variance weighted (IVW) method, with MR-Egger regression and weighted median as complementary approaches. Sensitivity analyses (Cochran's Q test, MR-Egger intercept, leave-one-out) and the Steiger test were applied to assess heterogeneity, pleiotropy, and causal directionality.

RESULTS

We observed a negative correlation between "39S ribosomal protein L34, mitochondrial", and others, with hepatic cancer, while "[Pyruvate dehydrogenase (acetyl-transferring)] kinase isozyme 2, mitochondrial", and others exhibited a positive correlation with hepatic cancer. "Phenylalanine-tRNA ligase, mitochondrial", and others demonstrated a negative association with colorectal cancer, whereas "Methylmalonyl-CoA epimerase, mitochondrial", and others exhibited a positive correlation with colorectal cancer. "Succinate dehydrogenase assembly factor 2, mitochondrial" exhibited a negative correlation with lung cancer, while "Superoxide dismutase [Mn], mitochondrial levels" showed a positive correlation with lung cancer. "Lon protease homolog, mitochondrial" demonstrated a positive correlation with esophageal cancer. "Iron-sulfur cluster assembly enzyme ISCU, mitochondrial", and others exhibited a negative correlation with thyroid cancer, while "Diablo homolog, mitochondrial", and others showed a positive correlation with thyroid cancer. "ADP-ribose pyrophosphatase, mitochondrial", and others exhibited a negative correlation with breast cancer, while "39S ribosomal protein L34, mitochondrial", and others showed a positive correlation with breast cancer.

CONCLUSIONS

This study provides MR-based evidence that specific mitochondrial-related traits have causal effects on the risk of several common cancers. Notably, certain single-nucleotide polymorphisms (SNPs) acted as instrumental variables across multiple cancer types through shared mitochondrial mechanisms, such as oxidative stress regulation and metabolic reprogramming. These findings highlight mitochondria as cross-cutting contributors to cancer susceptibility and suggest potential avenues for mitochondrial-targeted prevention and therapy. The identification of pleiotropic genetic variants also offers insights for developing shared biomarkers and therapeutic targets across malignancies.

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.

Photobiomodulation modulates mitochondrial energy metabolism and ameliorates neurological damage in an APP/PS1 mousmodel of Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease. Amyloid β-protein (Aβ) is one of the key pathological features of AD, which is cytotoxic and can damage neurons, thereby causing cognitive dysfunction. Photobiomodulation (PBM) is a non-invasive physical therapy that induces changes in the intrinsic mechanisms of cells and tissues through low-power light exposure. Although PBM has been employed in the treatment of AD, the effect and precise mechanism of PBM on AD-induced neurological damage are still unclear.

METHODS

In vivo experiments, PBM (808 nm, 20 mW/cm2) was used to continuously interfere with APP/PS1 mice for 6 weeks, and then their cognitive function and AD pathological changes were evaluated. In vitro experiments, lipopolysaccharide (LPS) was used to induce microglia to model inflammation, and the effect of PBM treatment on microglia polarization status and phagocytic Aβ ability was evaluated. Hexokinase 2 (HK2) inhibitor 3-bromopyruvate (3BP) was used to study the effect of PBM treatment on mitochondrial energy metabolism in microglia.

RESULTS

PBM further ameliorates AD-induced cognitive impairment by alleviating neuroinflammation and neuronal apoptosis, thereby attenuating nerve damage. In addition, PBM can also reduce neuroinflammation by promoting microglial anti-inflammatory phenotypic polarization; Promotes Aβ clearance by enhancing the ability of microglia to engulf Aβ. Among them, PBM regulates microglial polarization and inhibits neuronal apoptosis, which may be related to its regulation of mitochondrial energy metabolism, promotion of oxidative phosphorylation, and inhibition of glycolysis.

CONCLUSION

PBM regulates neuroinflammatory response and inhibits neuronal apoptosis, thereby repairing Aβ-induced neuronal damage and cognitive dysfunction. Mitochondrial energy metabolism plays an important role in PBM in improving nerve injury in AD mice. This study provides theoretical support for the subsequent application of PBM in the treatment of AD.

Oxidative phosphorylation and breast cancer progression: insights into PGC-1α's role in mitochondrial function

Breast cancer still ranks high as a leading cause of mortality in women due to its complex relationship with metabolic reprogramming and tumor progression. The peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), a key transcriptional coactivator regulating mitochondrial biogenesis and oxidative phosphorylation (OXPHOS), plays a dual role in breast cancer metabolism. On the one hand, PGC-1α enhances mitochondrial function and energy production, facilitating tumor survival and metastasis, particularly in hypoxic environments. On the other hand, its suppression can limit tumor aggressiveness and energy metabolism. This dual functionality underscores its context-dependent role in cancer progression, where its activation or inhibition varies across tumor subtypes and microenvironmental conditions. The purpose of this review is to provide a comprehensive understanding of PGC-1α's dual roles in breast cancer, elucidating its regulation of mitochondrial function, its contribution to tumor progression, and the therapeutic implications of targeting this key metabolic regulator.

Bioinformatics and experimental approach reveal potential prognostic and immunological roles of key mitochondrial metabolism-related genes in cervical cancer

Background

Metabolic remodeling is the hallmark of cancer. In recent years, mitochondrial metabolism (MM) has been considered essential in tumorigenesis and cancer progression. Understanding the role of MM in cervical cancer (CC) can provide insights into disease progression and potential therapeutic targets.

Methods

Clinical data of CC patients was downloaded from the UCSC Xena dataset, and differentially expressed genes (DEGs) were identified between tumor and normal samples. MM-related genes (MMRGs) were screened from the MSigDB database. DEGs and MMRGs were then intersected to identify differentially expressed MMRGs. A prognostic risk model was constructed based on these intersecting genes through Cox regression analysis, and its association with the tumor microenvironment and immune checkpoint-related genes was evaluated. Hub genes' expression was evaluated in cells through qRT-PCR. Additionally, drug sensitivity analysis was conducted to explore potential therapeutic drugs.

Results

We identified 259 overlapping genes between DEGs and MMRGs, with 55 being prognosis-related. Two molecular clusters were revealed, with C1 exhibiting poorer prognosis. A prognostic risk model comprising five genes (BDH1, MIR210, MSMO1, POLA1, and STARD3NL) was established, showing significant associations with survival outcomes of CC patients. Functional enrichment analysis revealed that DEGs between high- and low-risk groups were tightly associated with the immune system. Analysis of the immune microenvironment showed significant differences between different risk groups, with higher immune and ESTIMATE scores observed in the low-risk group. Additionally, expression levels of immune checkpoint-related genes were significantly correlated with the risk score. Drug sensitivity analysis identified potential therapeutic agents correlated with the expression of the five prognostic genes.

Conclusion

Our findings underscore the importance of MM in CC progression and provide potential therapeutic targets for CC.

Identification and validation of a prognostic signature of drug resistance and mitochondrial energy metabolism-related differentially expressed genes for breast cancer

BACKGROUND

Drug resistance constitutes one of the principal causes of poor prognosis in breast cancer patients. Although cancer cells can maintain viability independently of mitochondrial energy metabolism, they remain reliant on mitochondrial functions for the synthesis of new DNA strands. This dependency underscores a potential link between mitochondrial energy metabolism and drug resistance. Hence, drug resistance and mitochondrial energy metabolism-related differentially expressed genes (DMRDEGs) may emerge as candidates for novel cancer biomarkers. This study endeavors to assess the viability of DMRDEGs as biomarkers or therapeutic targets for breast cancer.

METHODS

We utilized the DRESIS database and MSigDB to identify genes related to drug resistance. Additionally, we sourced genes associated with mitochondrial energy metabolism from GeneCards and extant literature. By merging these genes with differentially expressed genes observed in normal and tumor tissues from the TCGA-BRCA and GEO databases, we successfully identified the DMRDEGs. Employing unsupervised consensus clustering, we divided breast cancer patients into two distinct groups based on the DMRDEGs. Consequently, we identified four hub genes to formulate a prognostic model, applying Cox regression, LASSO regression, and Random Forest methods. Furthermore, we examined immune infiltration and tumor mutation burden of the genes within our model and scrutinized divergences in the immune microenvironment between high- and low-risk groups. Small hairpin RNA and lentiviral plasmids were designed for stable transfection of breast cancer cell lines MDA-MB-231 and HCC1806. By conducting clone formation, scratch test, transwell assays, cell viability assay and measurement of oxygen consumption we initiated a preliminary investigation into mechanistic roles of AIFM1.

RESULTS

We utilized DMRDEGs to develop a prognostic model that includes four mRNAs for breast cancer. This model combined with various clinical features and critical breast cancer facets, demonstrated remarkable efficacy in predicting patient outcomes. AIFM1 appeared to enhance the proliferation, migration, and invasiveness of breast cancer cell lines MDA-MB-231 and HCC1806. Moreover, by reducing oxygen consumption, it aids in the cancer cells' acquisition of drug resistance.

CONCLUSIONS

DMRDEGs hold promise as diagnostic markers and therapeutic targets for breast cancer. Among the associated mutated genes, ATP7B, FUS, AIFM1, and PPARG could serve as early diagnostic indicators, and notably, AIFM1 may present itself as a promising therapeutic target.

The roles of KRAS in cancer metabolism, tumor microenvironment and clinical therapy

KRAS is one of the most mutated genes, driving alternations in metabolic pathways that include enhanced nutrient uptaking, increased glycolysis, elevated glutaminolysis, and heightened synthesis of fatty acids and nucleotides. However, the beyond mechanisms of KRAS-modulated cancer metabolisms remain incompletely understood. In this review, we aim to summarize current knowledge on KRAS-related metabolic alterations in cancer cells and explore the prevalence and significance of KRAS mutation in shaping the tumor microenvironment and influencing epigenetic modification via various molecular activities. Given that cancer cells rely on these metabolic changes to sustain cell growth and survival, targeting these processes may represent a promising therapeutic strategy for KRAS-driven cancers.

Targeting Caveolin-1 in Multiple Myeloma Cells Enhances Chemotherapy and Natural Killer Cell-Mediated Immunotherapy

The cell membrane transport capacity and surface targets of multiple myeloma (MM) cells heavily influence chemotherapy and immunotherapy. Here, it is found that caveolin-1 (CAV1), a primary component of membrane lipid rafts and caveolae, is highly expressed in MM cells and is associated with MM progression and drug resistance. CAV1 knockdown decreases MM cell adhesion to stromal cells and attenuates cell adhesion-mediated drug resistance to bortezomib. CAV1 inhibition in MM cells enhances natural killer cell-mediated cytotoxicity through increasing CXCL10, SLAMF7, and CD112. CAV1 suppression reduces mitochondrial membrane potential, increases reactive oxygen species, and inhibits autophagosome-lysosome fusion, resulting in the disruption of redox homeostasis. Additionally, CAV1 knockdown enhances glutamine addiction by increasing ASCT2 and LAT1 and dysregulates glutathione metabolism. As a result of CAV1 inhibition, MM cells are more sensitive to starvation, glutamine depletion, and glutamine transporter inhibition, and grow more slowly in vivo in a mouse model treated with bortezomib. The observation that CAV1 inhibition modulated by 6-mercaptopurine, daidzin, and statins enhances the efficacy of bortezomib in vitro and in vivo highlights the translational significance of these FDA-approved drugs in improving MM outcomes. These data demonstrate that CAV1 serves as a potent therapeutic target for enhancing chemotherapy and immunotherapy for MM.

Metabolic Reprogramming in Cancer: Implications for Immunosuppressive Microenvironment

Cancer is a complex and heterogeneous disease characterised by uncontrolled cell growth and proliferation. One hallmark of cancer cells is their ability to undergo metabolic reprogramming, which allows them to sustain their rapid growth and survival. This metabolic reprogramming creates an immunosuppressive microenvironment that facilitates tumour progression and evasion of the immune system. In this article, we review the mechanisms underlying metabolic reprogramming in cancer cells and discuss how these metabolic alterations contribute to the establishment of an immunosuppressive microenvironment. We also explore potential therapeutic strategies targeting metabolic vulnerabilities in cancer cells to enhance immune-mediated anti-tumour responses. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02044861, NCT03163667, NCT04265534, NCT02071927, NCT02903914, NCT03314935, NCT03361228, NCT03048500, NCT03311308, NCT03800602, NCT04414540, NCT02771626, NCT03994744, NCT03229278, NCT04899921.

Anticancer behavior of cyclometallated iridium(III)-tributyltin(IV) carboxylate schiff base complexes with aggregation-induced emission

Cyclometallated iridium(III) and organotin(IV) carboxylate complexes have shown potential application value in the field of anticancer. However, the widespread aggregation-caused quenching (ACQ) effect of these complexes is not conducive to the exploration of their targeting and anticancer mechanism, and the idea of aggregation-induced emission (AIE) effect can effectively solve this problem. Then, AIE-activated cyclometallated iridium(III)-tributyltin(IV) carboxylate Schiff base complexes were designed and prepared in this study. Complexes exhibited AIE effect in highly concentrated solution or aggregative state, which facilitated the investigation of subcellular tissue targeting (mitochondria) and cell morphology. Compared with cyclometallated iridium(III) complex and tributyltin(IV) carboxylate monomers, these complexes showed the better in-vitro anti-proliferative activity toward A549 cells, confirming the favorable synergistic anticancer activity. Even for A549/DDP (cisplatin-resistance) cells, these complexes also exhibited the better activity. In addition, complexes showed a mitochondrial apoptotic pathway. Therefore, cyclometallated iridium(III)-tributyltin(IV) carboxylate Schiff base complexes can be used as the potential substitutes for platinum-based drugs and gain further application.

MTHFD2-mediated redox homeostasis promotes gastric cancer progression under hypoxic conditions

OBJECTIVES

Cancer cells undergo metabolic reprogramming to adapt to high oxidative stress, but little is known about how metabolic remodeling enables gastric cancer cells to survive stress associated with aberrant reactive oxygen species (ROS) production. Here, we aimed to identify the key metabolic enzymes that protect gastric cancer (GC) cells from oxidative stress.

METHODS

ROS level was detected by DCFH-DA probes. Multiple cell biological studies were performed to identify the underlying mechanisms. Furthermore, cell-based xenograft and patient-derived xenograft (PDX) model were performed to evaluate the role of MTHFD2 in vivo.

RESULTS

We found that overexpression of MTHFD2, but not MTHFD1, is associated with reduced overall and disease-free survival in gastric cancer. In addition, MTHFD2 knockdown reduces the cellular NADPH/NADP+ ratio, colony formation and mitochondrial function, increases cellular ROS and cleaved PARP levels and induces in cell death under hypoxia, a hallmark of solid cancers and a common inducer of oxidative stress. Moreover, genetic or pharmacological inhibition of MTHFD2 reduces tumor burden in both tumor cell lines and patient-derived xenograft-based models.

DISCUSSION

our study highlights the crucial role of MTHFD2 in redox regulation and tumor progression, demonstrating the therapeutic potential of targeting MTHFD2.

Epitranscriptomics and cervical cancer: the emerging role of m6A, m5C and m1A RNA modifications

Cervical cancer (CC), one of the most prevalent and detrimental gynaecologic cancers, evolves through genetic and epigenetic alterations resulting in the promotion of oncogenic activity and dysfunction of tumour-suppressing mechanisms. Despite medical advancement, the prognosis for advanced-stage patients remains extremely low due to high recurrence rates and resistance to existing treatments. Thereby, the search for potential prognostic biomarkers is heightened to unravel new modalities of CC pathogenesis and to develop novel anti-cancer therapies. Epitranscriptomic modifications, reversible epigenetic RNA modifications, regulate various biological processes by deciding RNA fate to mediating RNA interactions. This narrative review provides insight into the cellular and molecular roles of endogenous RNA-editing proteins and their associated epitranscriptomic modifications, especially N6-methyladenosine (m6A), 5-methylcytosine (m5C) and N1-methyladenosine (m1A), in governing the development, progression and metastasis of CC. We discussed the in-depth epitranscriptomic mechanisms underlying the regulation of over 50 RNAs responsible for tumorigenesis, proliferation, migration, invasion, survival, autophagy, stemness, epithelial-mesenchymal transition, metabolism (glucose, lipid, glutamate and glutamine), resistance (drug and radiation), angiogenesis and recurrence of CC. Additionally, we provided a concise overview of the therapeutic potential of targeting the altered expression of endogenous RNA-editing proteins and aberrant deposition of RNA modifications on both coding and non-coding RNAs in CC.

Establishment of a prognostic model for pancreatic cancer based on mitochondrial metabolism related genes

AIM

Pancreatic ductal adenocarcinoma (PAAD) is recognized as an exceptionally aggressive cancer that both highly lethal and unfavorable prognosis. The mitochondrial metabolism pathway is intimately involved in oncogenesis and tumor progression, however, much remains unknown in this area. In this study, the bioinformatic tools have been used to construct a prognostic model with mitochondrial metabolism-related genes (MMRGs) to evaluate the survival, immune status, mutation profile, and drug sensitivity of PAAD patients.

METHOD

Univariate Cox regression and LASSO regression were used to screen the differentially expressed genes (DEGs), and multivariate Cox regression was used to develop the risk model. Kaplan-Meier estimator was employed to identify MMRGs signatures associated with overall survival (OS). ROC curves were utilized to evaluate the model's performance. Maftools, immunedeconv and CIBERSORT R packages were applied to analyze the gene mutation profiles and immune status. The corresponding sensitivity to pharmaceutical agents was assessed using oncoPredict R packages.

RESULTS

A prognostic model with five MMRGs was developed, which defined the patients as high-risk showed lower survival rates. There was good consistency among individuals categorized as high-risk, showing elevated rates of genetic alterations, particularly in the TP53 and KRAS genes. Furthermore, these patients exhibited increased levels of immunosuppression, characterized by an increased presence of macrophages, neutrophils, Th2 cells, and regulatory T cells. Additionally, high-risk patients showed increased sensitivity to Sabutoclax and Venetoclax.

CONCLUSION

By utilizing a gene signature associated with mitochondrial metabolism, a prognostic model has been established which could be a highly efficient method for predicting the outcomes of PAAD patients.

Exploring the prognostic landscape of oral squamous cell carcinoma through mitochondrial damage-related genes

Oral squamous cell carcinoma (OSCC), the most prevalent form of oral cancer, poses significant challenges to the medical community due to its high recurrence rate and low survival rate. Mitochondrial Damage-Related Genes (MDGs) have been closely associated with the occurrence, metastasis, and progression of OSCC. Consequently, we constructed a prognostic model for OSCC based on MDGs and identified potential mitochondrial damage-related biomarkers. Gene expression profiles and relevant clinical information were obtained from The Cancer Genome Atlas (TCGA) database. Differential analysis was conducted to identify MDGs associated with OSCC. COX analysis was employed to screen seven prognosis-related MDGs and build a prognostic prediction model for OSCC. Cases were categorized into low-risk or high-risk groups based on the optimal risk score threshold. Kaplan-Meier (KM) analysis revealed significant survival differences (P < 0.05). Additionally, the area under the ROC curve (AUC) for patient survival at 1 year, 3 years, and 5 years were 0.687, 0.704, and 0.70, respectively, indicating a high long-term predictive accuracy of the prognostic model. To enhance predictive accuracy, age, gender, risk score, and TN staging were incorporated into a nomogram and verified using calibration curves. Risk scoring based on MDGs was identified as a potential independent prognostic biomarker. Furthermore, BID and SLC25A20 were identified as two potential independent mitochondrial damage-related prognostic biomarkers, offering new therapeutic targets for OSCC.

Studies of Anticancer Activities In Vitro and In Vivo for Butyltin(IV)-Iridium(III) Imidazole-Phenanthroline Complexes with Aggregation-Induced Emission Properties

Organotin(IV) and iridium(III) complexes have shown good application potential in the field of anticancer; however, the aggregation-caused quenching (ACQ) effect induced by high concentration or dose has limited the research on their targeting and anticancer mechanism. Then, a series of aggregation-induced emission (AIE)-activated butyltin(IV)-iridium(III) imidazole-phenanthroline complexes were prepared in this study. Complexes exhibited significant fluorescence improvement in the aggregated state because of the restricted intramolecular rotation (RIR), accompanied by an absolute fluorescence quantum yield of up to 29.2% (IrSn9). Complexes demonstrated potential in vitro antiproliferative and antimigration activity against A549 cells, following a lysosomal-mitochondrial apoptotic pathway. Nude mouse models further confirmed that complexes had favorable in vivo antitumor and antimigration activity in comparison to cisplatin. Therefore, butyltin(IV)-iridium(III) imidazole-phenanthroline complexes possess the potential as potential substitutes for platinum-based drugs.

Recent Progress in Anti-Tumor Nanodrugs Based on Tumor Microenvironment Redox Regulation

The growth state of tumor cells is strictly affected by the specific abnormal redox status of the tumor microenvironment (TME). Moreover, redox reactions at the biological level are also central and fundamental to essential energy metabolism reactions in tumors. Accordingly, anti-tumor nanodrugs targeting the disruption of this abnormal redox homeostasis have become one of the hot spots in the field of nanodrugs research due to the effectiveness of TME modulation and anti-tumor efficiency mediated by redox interference. This review discusses the latest research results of nanodrugs in anti-tumor therapy, which regulate the levels of oxidants or reductants in TME through a variety of therapeutic strategies, ultimately breaking the original "stable" redox state of the TME and promoting tumor cell death. With the gradual deepening of study on the redox state of TME and the vigorous development of nanomaterials, it is expected that more anti-tumor nano drugs based on tumor redox microenvironment regulation will be designed and even applied clinically.

Critical roles and clinical perspectives of RNA methylation in cancer

RNA modification, especially RNA methylation, is a critical posttranscriptional process influencing cellular functions and disease progression, accounting for over 60% of all RNA modifications. It plays a significant role in RNA metabolism, affecting RNA processing, stability, and translation, thereby modulating gene expression and cell functions essential for proliferation, survival, and metastasis. Increasing studies have revealed the disruption in RNA metabolism mediated by RNA methylation has been implicated in various aspects of cancer progression, particularly in metabolic reprogramming and immunity. This disruption of RNA methylation has profound implications for tumor growth, metastasis, and therapy response. Herein, we elucidate the fundamental characteristics of RNA methylation and their impact on RNA metabolism and gene expression. We highlight the intricate relationship between RNA methylation, cancer metabolic reprogramming, and immunity, using the well-characterized phenomenon of cancer metabolic reprogramming as a framework to discuss RNA methylation's specific roles and mechanisms in cancer progression. Furthermore, we explore the potential of targeting RNA methylation regulators as a novel approach for cancer therapy. By underscoring the complex mechanisms by which RNA methylation contributes to cancer progression, this review provides a foundation for developing new prognostic markers and therapeutic strategies aimed at modulating RNA methylation in cancer treatment.

Mitochondrial Dysfunction by FADDosome Promotes Gastric Mucosal Injury in Portal Hypertensive Gastropathy

Mucosal epithelial death is an essential pathological characteristic of portal hypertensive gastropathy (PHG). FADDosome can regulate mucosal homeostasis by controlling mitochondrial status and cell death. However, it remains ill-defined whether and how the FADDosome is involved in the epithelial death of PHG. The FADDosome formation, mitochondrial dysfunction, glycolysis process and NLRP3 inflammasome activation in PHG from both human sections and mouse models were investigated. NLRP3 wild-type (NLRP3-WT) and NLRP3 knockout (NLRP3-KO) littermate models, critical element inhibitors and cell experiments were utilized. The mechanism underlying FADDosome-regulated mitochondrial dysfunction and epithelial death in PHG was explored. Here, we found that FADD recruited caspase-8 and receptor-interacting serine/threonine-protein kinase 1 (RIPK1) to form the FADDosome to promote Drp1-dependent mitochondrial fission and dysfunction in PHG. Also, FADDosome modulated NOX2 signaling to strengthen Drp1-dependent mitochondrial fission and alter glycolysis as well as enhance mitochondrial reactive oxygen species (mtROS) production. Moreover, due to the dysfunction of electron transport chain (ETC) and alteration of antioxidant enzymes activity, this altered glycolysis also contributed to mtROS production. Subsequently, the enhanced mtROS production induced NLRP3 inflammasome activation to result in the epithelial pyroptosis and mucosal injury in PHG. Thus, the FADDosome-regulated pathways may provide a potential therapeutic target for PHG.

Role of reactive oxygen species in myelodysplastic syndromes

Reactive oxygen species (ROS) serve as typical metabolic byproducts of aerobic life and play a pivotal role in redox reactions and signal transduction pathways. Contingent upon their concentration, ROS production not only initiates or stimulates tumorigenesis but also causes oxidative stress (OS) and triggers cellular apoptosis. Mounting literature supports the view that ROS are closely interwoven with the pathogenesis of a cluster of diseases, particularly those involving cell proliferation and differentiation, such as myelodysplastic syndromes (MDS) and chronic/acute myeloid leukemia (CML/AML). OS caused by excessive ROS at physiological levels is likely to affect the functions of hematopoietic stem cells, such as cell growth and self-renewal, which may contribute to defective hematopoiesis. We review herein the eminent role of ROS in the hematological niche and their profound influence on the progress of MDS. We also highlight that targeting ROS is a practical and reliable tactic for MDS therapy.

Targeting Pivotal Hallmarks of Cancer for Enhanced Therapeutic Strategies in Triple-Negative Breast Cancer Treatment-In Vitro, In Vivo and Clinical Trials Literature Review

This literature review provides a comprehensive overview of triple-negative breast cancer (TNBC) and explores innovative targeted therapies focused on specific hallmarks of cancer cells, aiming to revolutionize breast cancer treatment. TNBC, characterized by its lack of expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), presents distinct features, categorizing these invasive breast tumors into various phenotypes delineated by key elements in molecular assays. This article delves into the latest advancements in therapeutic strategies targeting components of the tumor microenvironment and pivotal hallmarks of cancer: deregulating cellular metabolism and the Warburg effect, acidosis and hypoxia, the ability to metastasize and evade the immune system, aiming to enhance treatment efficacy while mitigating systemic toxicity. Insights from in vitro and in vivo studies and clinical trials underscore the promising effectiveness and elucidate the mechanisms of action of these novel therapeutic interventions for TNBC, particularly in cases refractory to conventional treatments. The integration of targeted therapies tailored to the molecular characteristics of TNBC holds significant potential for optimizing clinical outcomes and addressing the pressing need for more effective treatment options for this aggressive subtype of breast cancer.

Mitochondria in Mesenchymal Stem Cells: Key to Fate Determination and Therapeutic Potential

Mesenchymal stem cells (MSCs) have become popular tool cells in the field of transformation and regenerative medicine due to their function of cell rescue and cell replacement. The dynamically changing mitochondria serve as an energy metabolism factory and signal transduction platform, adapting to different cell states and maintaining normal cell activities. Therefore, a clear understanding of the regulatory mechanism of mitochondria in MSCs is profit for more efficient clinical transformation of stem cells. This review highlights the cutting-edge knowledge regarding mitochondrial biology from the following aspects: mitochondrial morphological dynamics, energy metabolism and signal transduction. The manuscript mainly focuses on mitochondrial mechanistic insights in the whole life course of MSCs, as well as the potential roles played by mitochondria in MSCs treatment of transplantation, for seeking pivotal targets of stem cell fate regulation and stem cell therapy.

CircVMP1 promotes glycolysis and disease progression by upregulating HKDC1 in colorectal cancer

BACKGROUND

Circular RNAs (circRNAs) have been reported to play important roles in cancers. Here, we characterized circVMP1 (hsa_circ_0006508), an important circRNA which promoted glycolysis and disease progression in colorectal cancer (CRC). In this study, we aimed to explore the mechanism by which circVMP1 regulated tumor glycolysis and its related pathways in promoting CRC cell proliferation and metastasis.

METHODS

The expression level of circVMP1 in CRC tissues and adjacent normal tissues was detected using quantitative PCR. In vitro and in vivo functional experiments were used to evaluate the effects of circVMP1 in the regulation of CRC cell proliferation and migration. Mitochondrial stress tests and glycolysis stress tests were conducted to detect the effect of circVMP1 on oxidative phosphorylation and glycolysis. Dual-luciferase reporter and RNA immunoprecipitation assays were used to evaluate the interaction between circVMP1, miR-3167, and HKDC1.

RESULTS

We demonstrated that the level of circVMP1 was significantly upregulated in CRC tissues compared with normal tissues. In HCT116 and SW480 cells, overexpression of circVMP1 promoted proliferation, metastasis, and glycolysis. In vivo analysis indicated that circVMP1 accelerated the proliferation of xenograft tumors. As for the mechanism, overexpression of circVMP1 increased the levels of hexokinase domain component 1 (HKDC1) through competitive binding with miR-3167.

CONCLUSION

Our study reported that circVMP1 was one of the tumor driver genes that promoted CRC malignant progression and glycolysis by upregulating HKDC1. CircVMP1/miR-3167/HKDC1 was a signaling axis that might be a target for CRC therapy.

ENO2 promotes anoikis resistance in anaplastic thyroid cancer by maintaining redox homeostasis

Background

Anoikis presents a significant barrier in the metastasis of cancer. As the most aggressive type of thyroid cancer, anaplastic thyroid cancer (ATC) exhibits a high risk of metastasis and is characterized by high mortality. Therefore, investigating the molecular mechanisms of anoikis resistance in ATC is important for devising therapeutic targets in clinical research.

Methods

Differentially Expressed Genes were screened in ATC cells under attached and detached culture conditions with RNA-seq. Investigate the impact of enolase 2 (ENO2) on apoptosis and spheroid formation by gain and loss of function. Changes of reactive oxygen species (ROS), glutathione (GSH) and nicotinamide adenine dinucleotide phosphate (NADPH) were detected to assess redox balance. The transcriptional regulatory role of signal transducer and activator of transcription 1 (STAT1) on ENO2 was validated through Dual-Luciferase Reporter Gene Assay. Explore the impact of ENO2 expression on the formation of lung metastases in nude mice.

Results

We found that the glycolysis process was activated in detached ATC cells. Several genes in the glycolysis process, particularly ENO2, a member of the enolase superfamily was upregulated in ATC cells cultured in suspension. The upregulation of ENO2 enabled the maintenance of redox balance by supplying GSH and NADPH, thereby preventing cells from undergoing anoikis. In terms of mechanism, the expression of STAT1 was enhanced in anoikis resistance cells, which in turn positively regulated the expression of ENO2. In vivo, ENO2-suppressed ATC cells resulted in a significantly lower rate of lung colonization compared to control ATC cells.

Conclusions

Stable expression of ENO2 and the maintenance of redox balance played a pivotal role in facilitating anoikis resistance of ATC.

Characterization of PKCα-rutin interactions and their application as a treatment strategy for pulmonary arterial hypertension by inhibiting ferroptosis

As a common plant-derived dietary flavonoid, rutin receives widespread attention because of its good antioxidant bioactivities. Protein kinase Cα (PKCα) is a serine/threonine kinase that is involved in uncountable cellular processes, among which ferroptosis, a novel form of cell death, is triggered by lipid peroxidation and has been reported to be associated with pulmonary arterial hypertension (PAH). But it is still not well appreciated how rutin inhibits ferroptosis in PAH and what function PKCα has in this process. In this study, we first observed whether rutin could prevent PAH by attenuating ferroptosis with a PAH animal model and pulmonary artery smooth muscle cells (PASMCs) under hypoxia. Mitochondrial metabolomics and network pharmacology were employed to clarify the metabolic alterations and screen target proteins, and the results showed that PKCα was a vital node in rutin regulating mitochondrial metabolism related to ferroptosis in PAH. Based on molecular docking and multispectral analysis, we found that rutin could directly interact with PKCα through hydrogen bonds, which could induce static quenching, and then influence the secondary structure of PKCα. In conclusion, these findings mainly point to a novel mechanism that rutin protects PAH rats by modifying the structure and altering the activity of PKCα, and thus suppressing ferroptosis. This work reveals that the interaction behaviors between small molecules and bio-macromolecules are a critical factor to develop natural biological active ingredients and gives an insight into the potential applications of flavonoids in health and disease.

HDAC1-Mediated Downregulation of NEU1 Exacerbates the Aggressiveness of Cervical Cancer

HDAC1 functions as an oncogene in multi-type cancers. This study aimed to investigate the roles of histone deacetylase 1 (HDAC1) in cervical cancer (CC). mRNA expression was determined using reverse transcription quantitative polymerase chain reaction. The protein-protein complexes was analyzed using co-immunoprecipitation assay. The binding sites between NRF2 and NEU1 were confirmed by chromatin immunoprecipitation assay. Cell viability was detected by CCK-8. Cell proliferation was measured using CCK-8 and colony formation assays. Cell migrative and invasive ability were determined using transwell assay. We found that HDAC1 was upregulated in CC patients and cells. Trichostatin A (TSA) treatment decreased the number of colonies and migrated and invaded cells. Moreover, HDAC1 interacted with NRF2 to downregulate NEU1 expression. NEU1 knockdown attenuated the effects of TSA and enhanced the aggressiveness of CC cells. In conclusion, HDAC1 functions as an oncogene in CC. Targeting HDAC1 may be an alternative strategy for CC.

Effect of HPV Oncoprotein on Carbohydrate and Lipid Metabolism in Tumor Cells

High-risk HPV infection accounts for 99.7% of cervical cancer, over 90% of anal cancer, 50% of head and neck cancers, 40% of vulvar cancer, and some cases of vaginal and penile cancer, contributing to approximately 5% of cancers worldwide. The development of cancer is a complex, multi-step process characterized by dysregulation of signaling pathways and alterations in metabolic pathways. Extensive research has demonstrated that metabolic reprogramming plays a key role in the progression of various cancers, such as cervical, head and neck, bladder, and prostate cancers, providing the material and energy foundation for rapid proliferation and migration of cancer cells. Metabolic reprogramming of tumor cells allows for the rapid generation of ATP, aiding in meeting the high energy demands of HPV-related cancer cell proliferation. The interaction between Human Papillomavirus (HPV) and its associated cancers has become a recent focus of investigation. The impact of HPV on cellular metabolism has emerged as an emerging research topic. A significant body of research has shown that HPV influences relevant metabolic signaling pathways, leading to cellular metabolic alterations. Exploring the underlying mechanisms may facilitate the discovery of biomarkers for diagnosis and treatment of HPV-associated diseases. In this review, we introduced the molecular structure of HPV and its replication process, discussed the diseases associated with HPV infection, described the energy metabolism of normal cells, highlighted the metabolic features of tumor cells, and provided an overview of recent advances in potential therapeutic targets that act on cellular metabolism. We discussed the potential mechanisms underlying these changes. This article aims to elucidate the role of Human Papillomavirus (HPV) in reshaping cellular metabolism and the application of metabolic changes in the research of related diseases. Targeting cancer metabolism may serve as an effective strategy to support traditional cancer treatments, as metabolic reprogramming is crucial for malignant transformation in cancer.

The role of RNA modification in urological cancers: mechanisms and clinical potential

RNA modification is a post-transcriptional level of regulation that is widely distributed in all types of RNAs, including mRNA, tRNA, rRNA, miRNA, and lncRNA, where N6-methyladenine (m6A) is the most abundant mRNA methylation modification. Significant evidence has depicted that m6A modifications are closely related to human diseases, especially cancer, and play pivotal roles in RNA transcription, splicing, stabilization, and translation processes. The most common urological cancers include prostate, bladder, kidney, and testicular cancers, accounting for a certain proportion of human cancers, with an ever-increasing incidence and mortality. The recurrence, systemic metastasis, poor prognosis, and drug resistance of urologic tumors have prompted the identification of new therapeutic targets and mechanisms. Research on m6A modifications may provide new solutions to the current puzzles. In this review, we provide a comprehensive overview of the key roles played by RNA modifications, especially m6A modifications, in urologic cancers, as well as recent research advances in diagnostics and molecularly targeted therapies.

A novel CPT1A covalent inhibitor modulates fatty acid oxidation and CPT1A-VDAC1 axis with therapeutic potential for colorectal cancer

Colorectal cancer (CRC) is a common and deadly disease of the digestive system, but its targeted therapy is hampered by the lack of reliable and specific biomarkers. Hence, discovering new therapeutic targets and agents for CRC is an urgent and challenging task. Here we report that carnitine palmitoyltransferase 1A (CPT1A), a mitochondrial enzyme that catalyzes fatty acid oxidation (FAO), is a potential target for CRC treatment. We show that CPT1A is overexpressed in CRC cells and that its inhibition by a secolignan-type compound, 2,6-dihydroxypeperomin B (DHP-B), isolated from the plant Peperomia dindygulensis, suppresses tumor cell growth and induces apoptosis. We demonstrate that DHP-B covalently binds to Cys96 of CPT1A, blocks FAO, and disrupts the mitochondrial CPT1A-VDAC1 interaction, leading to increased mitochondrial permeability and reduced oxygen consumption and energy metabolism in CRC cells. We also reveal that CPT1A expression correlates with the survival of tumor-bearing animals and that DHP-B exhibits anti-CRC activity in vitro and in vivo. Our study uncovers the molecular mechanism of DHP-B as a novel CPT1A inhibitor and provides a rationale for its preclinical development as well as a new strategy for CRC targeted therapy.

New insights into redox-related risk factors and therapeutic targets in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common cancer in the oral cavity accounting for 90 % of oral cancer with a global incidence of 350.000 new cases per year. Curative resection along with adjuvant radiation therapy or a combination of radiotherapy with chemotherapy remain as gold standard in treating OSCC. Still, local recurrence, lymph nodal recurrence, and complications of radiation remain the main cause of tumor-related mortality. Reactive oxygen species are not only correlated to the etiology of OSCC due to oxidative DNA damage, lipid peroxidation or effecting signal transduction cascades that effect cell proliferation and tumorigenesis, but are also of great interest in the therapy of OSCC patients. As induced oxidative stress can be used therapeutically for the induction of tumor cell death, redox targets might be a therapeutic addition to the conventional treatment options. In this review, we discuss markers of impaired redox homeostasis as well as potential redox-related treatment targets in OSCC.

The mitochondrial energy metabolism pathway-related signature predicts prognosis and indicates immune microenvironment infiltration in osteosarcoma

BACKGROUND

Abnormalities in the mitochondrial energy metabolism pathways are closely related to the occurrence and development of many cancers. Furthermore, abnormal genes in mitochondrial energy metabolism pathways may be novel targets and biomarkers for the diagnosis and treatment of osteosarcoma. In this study, we aimed to establish a mitochondrial energy metabolism-related gene signature for osteosarcoma prognosis.

METHODS

We first obtained differentially expressed genes based on the metastatic status of 84 patients with osteosarcoma from the TARGET database. After Venn analysis of differentially expressed genes and mitochondrial energy metabolism pathway-related genes (MMRGs), 2 key genes were obtained using univariate Cox regression and least absolute shrinkage and selection operator (LASSO) regression analysis. Next, we used these 2 genes to establish a prognostic signature. Subsequent analyses elucidated the correlation between these 2 key genes with clinical features and 28 types of immune cells. Pathway changes in osteosarcoma pathogenesis under different metastatic states were clarified using gene set enrichment analysis (GSEA) of differentially expressed genes.

RESULTS

A gene signature composed of 2 key prognosis-related genes (KCNJ5 and PFKFB2) was identified. A risk score was calculated based on the gene signature, which divided osteosarcoma patients into low- or high-risk groups that showed good and poor prognosis, respectively. High expression of these 2 key genes is associated with low-risk group in patients with osteosarcoma. We constructed an accurate nomogram to help clinicians assess the survival time of patients with osteosarcoma. The results of immune cell infiltration level showed that the high-risk group had lower levels of immune cell infiltration. GSEA revealed changes in immune regulation and hypoxia stress pathways in osteosarcoma under different metastatic states.

CONCLUSION

Our study identified an excellent gene signature that could be helpful in improving the prognosis of patients with osteosarcoma.

Identification of mitochondrial-related signature and molecular subtype for the prognosis of osteosarcoma

Mitochondria play a vital role in osteosarcoma. Therefore, the purpose of this study was to investigate the potential role of mitochondrial-related genes (MRGs) in osteosarcoma. Based on 92 differentially expressed MRGs, osteosarcoma samples were divided into two subtypes using the nonnegative matrix factorization (NMF). Ultimately, a univariate, least absolute shrinkage and selection operator (LASSO), and multivariate Cox analysis were performed to construct a prognostic risk model. The single-sample gene set enrichment analysis assessed the immune infiltration characteristics of osteosarcoma patients. Finally, we identified an osteosarcoma biomarker, malonyl-CoA decarboxylase (MLYCD), which showed downregulation. Osteosarcoma cells proliferation, migration, and invasion were effectively inhibited by the overexpression of MLYCD. Our findings will help us to further understand the molecular mechanisms of osteosarcoma and contribute to the discovery of new diagnostic biomarkers and therapeutic targets.

Responsive calcium-derived nanoassemblies induce mitochondrial disorder to promote tumor calcification

Physiological calcification of the treated tumor area is considered to be a predictor of good prognosis. Promoting tumor calcification by inducing mitochondrial metabolic disorder and destroying calcium equilibrium has a potential inhibitory effect on tumor proliferation. Here, by promoting calcification by inducing mitochondrial dysfunction combined with triggering a surge of reactive oxygen species, we construct a bioresponsive calcification initiator, termed CaP-AA, using CaHPO4 covalently doped l-ascorbic acid. CaHPO4 releases Ca2+ within the cytoplasm of tumor cells to trigger calcium overload. Meanwhile, exogenous l-ascorbic acid indirectly enhances metabolic balance disruption via pro-oxidant effects. Such Ca2+ overload increases the likelihood of tumor calcification in vivo for tumor inhibition by perturbing mitochondrial homeostasis. The introduction of responsive calcium sources that would, in turn, trigger intratumoral calcification mediated by perturbing mitochondrial homeostasis would be an effective regulatory strategy for tumor therapy.

A proximity labeling strategy enables proteomic analysis of inter-organelle membrane contacts

Inter-organelle membrane contacts are highly dynamic and act as central hubs for many biological processes, but the protein compositions remain largely unknown due to the lack of efficient tools. Here, we developed BiFCPL to analyze the contact proteome in living cells by a bimolecular fluorescence complementation (BiFC)-based proximity labeling (PL) strategy. BiFCPL was applied to study mitochondria-endoplasmic reticulum contacts (MERCs) and mitochondria-lipid droplet (LD) contacts. We identified 403 highly confident MERC proteins, including many transiently resident proteins and potential tethers. Moreover, we demonstrated that mitochondria-LD contacts are sensitive to nutrient status. A comparative proteomic analysis revealed that 60 proteins are up- or downregulated at contact sites under metabolic challenge. We verified that SQLE, an enzyme for cholesterol synthesis, accumulates at mitochondria-LD contact sites probably to utilize local ATP for cholesterol synthesis. This work provides an efficient method to identify key proteins at inter-organelle membrane contacts in living cells.

Gut microbes involvement in gastrointestinal cancers through redox regulation

Gastrointestinal (GI) cancers are among the most common and lethal cancers worldwide. GI microbes play an important role in the occurrence and development of GI cancers. The common mechanisms by which GI microbes may lead to the occurrence and development of cancer include the instability of the microbial internal environment, secretion of cancer-related metabolites, and destabilization of the GI mucosal barrier. In recent years, many studies have found that the relationship between GI microbes and the development of cancer is closely associated with the GI redox level. Redox instability associated with GI microbes may induce oxidative stress, DNA damage, cumulative gene mutation, protein dysfunction and abnormal lipid metabolism in GI cells. Redox-related metabolites of GI microbes, such as short-chain fatty acids, hydrogen sulfide and nitric oxide, which are involved in cancer, may also influence GI redox levels. This paper reviews the redox reactions of GI cells regulated by microorganisms and their metabolites, as well as redox reactions in the cancer-related GI microbes themselves. This study provides a new perspective for the prevention and treatment of GI cancers.

Why Metformin Should Not Be Used as an Oxidative Phosphorylation Inhibitor in Cancer Patients

BACKGROUND

Preclinical studies have suggested that metformin exerts antitumor effects on various types of cancers. However, the results of human clinical trials have been inconsistent.

SUMMARY

Metformin is widely considered to be a prime example of a clinically relevant compound that inhibits oxidative phosphorylation (OXPHOS). However, the efficacy of metformin in inhibiting OXPHOS in cancer patients remains uncertain. The available evidence suggests that the plasma concentration of metformin remains within the micromolar range when administered at therapeutic doses. While millimolar concentrations are necessary to inhibit complex I activity in isolated mitochondria, there is no evidence supporting the idea that metformin accumulates within the mitochondria. Metformin exerts a modest effect on the adenosine diphosphate to adenosine triphosphate (ATP) ratio, resulting in AMP-activated protein kinase activation, which promotes ATP-generating catabolic pathways and restores cellular energy balance.

KEY MESSAGES

The value of metformin as an OXPHOS inhibitor for cancer treatment is debatable, and caution should be exercised while using metformin for this purpose.

Isoespintanol Antifungal Activity Involves Mitochondrial Dysfunction, Inhibition of Biofilm Formation, and Damage to Cell Wall Integrity in Candida tropicalis

The growing increase in infections caused by C. tropicalis, associated with its drug resistance and consequent high mortality, especially in immunosuppressed people, today generates a serious global public health problem. In the search for new potential drug candidates that can be used as treatments or adjuvants in the control of infections by these pathogenic yeasts, the objective of this research was to evaluate the action of isoespintanol (ISO) against the formation of fungal biofilms, the mitochondrial membrane potential (ΔΨm), and its effect on the integrity of the cell wall. We report the ability of ISO to inhibit the formation of biofilms by up to 89.35%, in all cases higher than the values expressed by amphotericin B (AFB). Flow cytometric experiments using rhodamine 123 (Rh123) showed the ability of ISO to cause mitochondrial dysfunction in these cells. Likewise, experiments using calcofluor white (CFW) and analyzed by flow cytometry showed the ability of ISO to affect the integrity of the cell wall by stimulating chitin synthesis; these changes in the integrity of the wall were also observed through transmission electron microscopy (TEM). These mechanisms are involved in the antifungal action of this monoterpene.

Role of UCP2 in the Energy Metabolism of the Cancer Cell Line A549

The uncoupling protein UCP2 is a mitochondrial carrier for which transport activity remains controversial. The physiological contexts in which UCP2 is expressed have led to the assumption that, like UCP1, it uncouples oxidative phosphorylation and thereby reduces the generation of reactive oxygen species. Other reports have involved UCP2 in the Warburg effect, and results showing that UCP2 catalyzes the export of matrix C4 metabolites to facilitate glutamine utilization suggest that the carrier could be involved in the metabolic adaptations required for cell proliferation. We have examined the role of UCP2 in the energy metabolism of the lung adenocarcinoma cell line A549 and show that UCP2 silencing decreased the basal rate of respiration, although this inhibition was not compensated by an increase in glycolysis. Silencing did not lead to either changes in proton leakage, as determined by the rate of respiration in the absence of ATP synthesis, or changes in the rate of formation of reactive oxygen species. The decrease in energy metabolism did not alter the cellular energy charge. The decreased cell proliferation observed in UCP2-silenced cells would explain the reduced cellular ATP demand. We conclude that UCP2 does not operate as an uncoupling protein, whereas our results are consistent with its activity as a C4-metabolite carrier involved in the metabolic adaptations of proliferating cells.

Study on the role and pharmacology of cuproptosis in gastric cancer

Objective

Gastric cancer has a poor prognosis and high mortality. Cuproptosis, a novel programmed cell death, is rarely studied in gastric cancer. Studying the mechanism of cuproptosis in gastric cancer is conducive to the development of new drugs, improving the prognosis of patients and reducing the burden of disease.

Methods

The TCGA database was used to obtain transcriptome data from gastric cancer tissues and adjacent tissues. GSE66229 was used for external verification. Overlapping genes were obtained by crossing the genes obtained by differential analysis with those related to copper death. Eight characteristic genes were obtained by three dimensionality reduction methods: lasso, SVM, and random forest. ROC and nomogram were used to estimate the diagnostic efficacy of characteristic genes. The CIBERSORT method was used to assess immune infiltration. ConsensusClusterPlus was used for subtype classification. Discovery Studio software conducts molecular docking between drugs and target proteins.

Results

We have established the early diagnosis model of eight characteristic genes (ENTPD3, PDZD4, CNN1, GTPBP4, FPGS, UTP25, CENPW, and FAM111A) for gastric cancer. The results are validated by internal and external data, and the predictive power is good. The subtype classification and immune type analysis of gastric cancer samples were performed based on the consensus clustering method. We identified C2 as an immune subtype and C1 as a non-immune subtype. Small molecule drug targeting based on genes associated with cuproptosis predicts potential therapeutics for gastric cancer. Molecular docking revealed multiple forces between Dasatinib and CNN1.

Conclusion

The candidate drug Dasatinib may be effective in treating gastric cancer by affecting the expression of the cuproptosis signature gene.

Loss of mammalian glutaminase orthologs impairs sperm function in Caenorhabditis elegans

The decline in sperm function is a major cause of human male infertility. Glutaminase, a mitochondrial enzyme that catalyzes the hydrolysis of glutamine to generate glutamate, takes part in many diverse biological processes such as neurotransmission, metabolism, and cellular senescence. Here we report the role of glutaminase in regulating sperm function. By generating a triple mutant that harbors a loss-of-function allele for each of all three mammalian glutaminase orthologs, we found that glutaminase gene activity is required for optimal Caenorhabditis elegans sperm function. Tissue-specific gene manipulations showed that germline glutaminase activity plays an important role. Moreover, transcriptional profiling and antioxidant treatment suggested that glutaminase promotes sperm function by maintaining cellular redox homeostasis. As maintaining a low level of ROS is crucial to human sperm function, it is very likely that glutaminase plays a similar role in humans and therefore can be a potential target for treating human male infertility.

Protein persulfidation: Rewiring the hydrogen sulfide signaling in cell stress response

The past few decades have witnessed significant progress in the discovery of hydrogen sulfide (H₂S) as a ubiquitous gaseous signaling molecule in mammalian physiology, akin to nitric oxide and carbon monoxide. As the third gasotransmitter, H₂S is now known to exert a wide range of physiological and cytoprotective functions in the biological systems. However, endogenous H₂S concentrations are usually low, and its potential biologic mechanisms responsible have not yet been fully clarified. Recently, a growing body of evidence has demonstrated that protein persulfidation, a posttranslational modification of cysteine residues (RSH) to persulfides (RSSH) elicited by H₂S, is a fundamental mechanism of H₂S-mediated signaling pathways. Persulfidation, as a biological switch for protein function, plays an important role in the maintenance of cell homeostasis in response to various internal and external stress stimuli and is also implicated in numerous diseases, such as cardiovascular and neurodegenerative diseases and cancer. In this review, the biological significance of protein persulfidation by H₂S in cell stress response is reviewed providing a framework for understanding the multifaceted roles of H₂S. A mechanism-guided perspective can help open novel avenues for the exploitation of therapeutics based on H₂S-induced persulfidation in the context of diseases.

In Vitro and In Vivo Antitumor Assay of Mitochondrially Targeted Fluorescent Half-Sandwich Iridium(III) Pyridine Complexes

Half-sandwich iridium(III) complexes show potential value in the anticancer field. However, complexes with favorable luminescence performance are rare, which limits further investigation of the anticancer mechanism. In this paper, 10 triphenylamine-modified fluorescent half-sandwich iridium(III) pyridine complexes {[(η⁵-Cp^x)Ir(L)Cl₂]} (Ir1-Ir10) were prepared and showed potential antiproliferative activity, effectively inhibiting the migration of A549 cells. Ir6, showing the best activity among these complexes, exhibited excellent fluorescence performance (absolute fluorescence quantum yield of 15.17%) in solution. Laser confocal detection showed that Ir6 followed an energy-dependent cellular uptake mechanism, specifically accumulating in mitochondria (Pearson co-localization coefficient of 0.95). A Western blot assay further confirmed the existence of a mitochondrial apoptotic channel. Additionally, Ir6 could arrest the cell cycle at the G₂/M phase, catalyze NADH oxidation, reduce the mitochondrial membrane potential, induce an increase in the level of intracellular reactive oxygen species, and exhibit a mechanism of oxidation. An in vivo antitumor assay confirmed that Ir6 can effectively inhibit tumor growth and is safer than cisplatin.

Comprehensive analysis reveals signal and molecular mechanism of mitochondrial energy metabolism pathway in pancreatic cancer

Pancreatic cancer (PAAD) is one of the most malignant tumors with the worst prognosis. The abnormalities in the mitochondrial energy metabolism pathway are intimately correlated with the occurrence and progression of cancer. For the diagnosis and treatment of pancreatic cancer, abnormal genes in the mitochondrial energy metabolism system may offer new targets and biomarkers. In this study, we compared the dysregulated mitochondrial energy metabolism-associated pathways in PAAD based on pancreatic cancer samples in the Cancer Genome Atlas (TCGA) database and normal pancreas samples from the Genotype Tissue Expression project (GTEx) database. Then identified 32 core genes of mitochondrial energy metabolism pathway-related genes (MMRG) were based on the gene set enrichment analysis (GSEA). We found most of these genes were altered among different clinical characteristic groups, and showed significant prognostic value and association with immune infiltration, suggesting critical roles of MMRG involve tumor genesis of PAAD. Therefore, we constructed a four-gene (LDHA, ALDH3B1, ALDH3A1, and ADH6) prognostic biomarker after eliminating redundant factors, and confirming its efficiency and independence. Further analysis indicated the potential therapeutic compounds based on the mitochondrial energy metabolism-associated prognostic biomarker. All of the above analyses dissected the critical role of mitochondrial energy metabolism signaling in pancreatic cancer and gave a better understanding of the clinical intervention of PAAD.

Multifaceted roles of aerobic glycolysis and oxidative phosphorylation in hepatocellular carcinoma

Liver cancer is a common malignancy with high morbidity and mortality rates. Changes in liver metabolism are key factors in the development of primary hepatic carcinoma, and mitochondrial dysfunction is closely related to the occurrence and development of tumours. Accordingly, the study of the metabolic mechanism of mitochondria in primary hepatic carcinomas has gained increasing attention. A growing body of research suggests that defects in mitochondrial respiration are not generally responsible for aerobic glycolysis, nor are they typically selected during tumour evolution. Conversely, the dysfunction of mitochondrial oxidative phosphorylation (OXPHOS) may promote the proliferation, metastasis, and invasion of primary hepatic carcinoma. This review presents the current paradigm of the roles of aerobic glycolysis and OXPHOS in the occurrence and development of hepatocellular carcinoma (HCC). Mitochondrial OXPHOS and cytoplasmic glycolysis cooperate to maintain the energy balance in HCC cells. Our study provides evidence for the targeting of mitochondrial metabolism as a potential therapy for HCC.

PUS1 May Be a Potential Prognostic Biomarker and Therapeutic Target for Hepatocellular Carcinoma

Objective

The mechanisms of pseudouridine synthase (PUS) are not definite in hepatocellular carcinoma (HCC), the objective of this study is to investigate the effect of PUS genes in HCC.

Materials and Methods

Differentially expressed and prognostic gene of PUS enzymes was identified based on The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Gene Expression Profiling Interactive Analysis (GEPIA) databases. For the identified gene, pseudouridine synthase 1 (PUS1), was used for further research. The clinicopathological feature of PUS1 was analyzed by Student's t-test. Prognostic significance was explored by Kaplan-Meier (KM) analysis and Cox proportional hazards regression model. Receiver operating characteristic (ROC) curve was applied to appraise diagnostic and prognostic value. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) and Gene Set Enrichment Analysis (GSEA) were implemented to explore mechanism of PUS1. A Guangxi cohort was applied to verify differential expression. In vitro cell experiments were implemented to investigate the influence for proliferation, reactive oxygen species (ROS) level, migration, and invasion of HCC cells after a knockdown of PUS1.

Results

PUS1 was significantly overexpressed in HCC tissues, and patients with high PUS1 were related to unpromising clinicopathological features. Survival analysis revealed high PUS1 expression was associated with a poor overall survival (OS) and 1 year-recurrence free survival (RFS), was an independent risk factor. Meanwhile, ROC curve showed that PUS1 had a diagnostic and prognostic significance to HCC. Functional enrichment analysis implied that PUS1 may be involved in metabolic pathways, mitochondrial function, non-alcoholic fatty liver disease (NAFLD), and some important carcinogenic pathways. Cell assays revealed that knockdown of PUS1 significantly constrained the migration, proliferation, invasion and improved the ROS level of HCC cells.

Conclusion

PUS1 may be a prognostic biomarker and a underlying treatment target for HCC.

Bioinspired nanocatalytic tumor therapy by simultaneous reactive oxygen species generation enhancement and glutamine pathway-mediated glutathione depletion

An insufficient intracellular H₂O₂ level and overexpressed glutathione (GSH) are still the major challenges for effective chemodynamic therapy (CDT). Inspired by the unique glutamine metabolism pathway in cancer cells, herein, intelligent nanocatalytic theranostics is used to enhance intracellular reactive oxygen species (ROS) accumulation via the production of H₂O₂ by a biomimetic nanozyme, and simultaneously reduce ROS consumption via the depression of GSH synthesis by the glutamine metabolic inhibitor. In this reactor, nano-sized Au and Fe₃O₄ coloaded dendritic mesoporous silica nanoparticles (DMSN-Au-Fe₃O₄) serve as the bifunctional nanozyme, where intracellular glucose is catalyzed into H₂O₂ by the glucose oxidase-mimicking Au nanoparticles and then immediately transformed into ˙OH by the peroxidase-like Fe₃O₄ nanoparticles. Then, CB839, the glutaminase (GLS) inhibitor, is grafted on the nanozyme, blocking the glutamine pathway and GSH biosynthesis. As a result, the as-designed nanoplatform with a three-pronged integration of Au-mediated H₂O₂ self-supply, Fe₃O₄-triggered Fenton-like reaction, and glutamine pathway-mediated GSH depletion significantly boosts the CDT efficacy, achieving remarkable and specific antitumor properties both in vitro and in vivo. This work not only paves a new way for rationally designing multi-functional nanozymes for achieving high therapeutic efficacy, but also provides new insights into the construction of bioinspired synergetic therapy by combining CDT and a key anticancer pathway.

Androgen receptor signaling-mitochondrial DNA-oxidative phosphorylation: A critical triangle in early prostate cancer

Mitochondria are more than just the cellular powerhouse. They also play key roles in vital functions such as apoptosis, metabolism regulation, and other intracellular interactions. The mitochondrial DNA (mtDNA) encodes for 12 subunits of the oxidative phosphorylation (OXPHOS) system. Depletion of mtDNA in androgen-dependent prostate cancer (PCa) cell lines renders them androgen-independent and more aggressive. Paradoxically, pharmaceutical inhibition of OXPHOS is lethal for subsets of PCa cells, whereas others become dependent on androgen receptor (AR) signaling for survival. Given that the AR-mitochondria interaction is critical for early PCa, it is crucial to understand the details of this interaction. Technical hurdles have made mitochondria traditionally difficult to study, with many techniques used for isolation masking the properties of given individual mitochondria. Although the isolation of mitochondria enables us to study OXPHOS, we miss the context in which mitochondria interact with the rest of the cell. Both AR signaling and mtDNA affect apoptosis, metabolism regulation, cellular calcium storage and homeostasis, intracellular calcium signaling, and redox homeostasis. In this review, we will attempt to understand how the crosstalk between AR-mtDNA-OXPHOS is responsible for "life or death" decisions inside the cells. Our aim is to point toward potential vulnerabilities that can lead to the discovery of novel therapeutic targets.

Molecular Subtypes Based on Cuproptosis-Related Genes and Tumor Microenvironment Infiltration Characterization in Colorectal Cancer

Recent studies have demonstrated the biological significance of cuproptosis modification, a newly discovered programmed cell death, in tumor progression. Nonetheless, the potential role of cuproptosis-related genes (CRGs) in the immune landscape and tumor microenvironment (TME) formation of colorectal cancer (CRC) remains unknown. We comprehensively assessed cuproptosis modification patterns of 1339 CRC samples based on 27 CRGs and systematically analyzed the correlation of these patterns with TME. The CRG-score was constructed to quantify cuproptosis characteristics by LASSO and multivariate Cox regression methods, and its predictive capability was validated in an independent cohort. We identified three distinct cuproptosis modification patterns in CRC. The TME immune cell infiltration demonstrated immune heterogeneity among these three subtypes. Enrichment for multiple metabolism signatures was pronounced in cluster A. Cluster C was significantly correlated with the signaling pathways of immune activation-related, resulting in poor prognoses. Cluster B with mixed features possibly represents a transition phenotype or intratumoral heterogeneity. Then, based on constructed eight-gene CRG-score, we found that the signature could predict the disease-free survival of CRC patients, and the low CRG-score was related to increased neoantigen load, immunity activation, and microsatellite instability-high (MSI-H). Additionally, we observed significant correlations of the CRG-score with the cancer stem cell index and chemotherapeutic drug susceptibility. This study demonstrated that cuproptosis was correlated with tumor progression, prognosis, and TME. Our findings may improve the understanding of CRGs in TME infiltration characterization of CRC patients and contribute to guiding more effective clinical therapeutic strategies.