Cancer remains a significant barrier to human longevity and a leading cause of mortality worldwide. Despite advancements in cancer therapies, challenges such as cellular toxicity and drug resistance to chemotherapy persist. Regulated cell death (RCD), once regarded as a passive process, is now recognized as a programmed mechanism with distinct biochemical and morphological characteristics, thereby presenting new therapeutic opportunities. Ferroptosis, a novel form of RCD characterized by iron-dependent lipid peroxidation and unique mitochondrial damage, differs from apoptosis, autophagy, and necroptosis. It is driven by reactive oxygen species (ROS)-induced lipid peroxidation and is implicated in tumorigenesis, anti-tumor immunity, and resistance, particularly in tumors undergoing epithelial-mesenchymal transition. Moreover, ferroptosis is associated with ischemic organ damage, degenerative diseases, and aging, regulated by various cellular metabolic processes, including redox balance, iron metabolism, and amino acid, lipid, and glucose metabolism. This review focuses on the role of epigenetic factors in tumor ferroptosis, exploring their mechanisms and potential applications in cancer therapy. It synthesizes current knowledge to provide a comprehensive understanding of epigenetic regulation in tumor cell ferroptosis, offering insights for future research and clinical applications.

Clear cell renal cell carcinoma (ccRCC) represents the most prevalent histological subtype and primary contributor to unfavorable prognosis in renal cancer. While mitochondrial dynamics serve as a critical quality control mechanism linked to tumor malignancy, their clinical significance and specific mechanisms in ccRCC remain poorly understood.

Consnsuclusterplus was used to consensus clustering and molecular subtype screening, Kaplan-Meier analysis was used to analyze survival in different subtypes. PINK1 expression was detected by westernblot, and CCK8 is used to detect cell activity. Immunofluorescence staining of LC3 for evaluating mitochondrial autophagy levels.

In this study, we classified 534 ccRCC samples, identified from the UCSC XENA database, into A and B clusters based on 42 mitochondrial dynamic related genes. Cluster A demonstrated superior survival outcomes compared to cluster B. Subsequent analysis revealed significant inter-cluster differences in gene expression profiles, mutational spectra, and immune infiltration patterns. We established a mitochondrial dynamics-related prognostic model incorporating PINK1, NIPSNAP1, and MTFR2, with mitophagy-associated genes represented by PINK1 showing particular prognostic significance in ccRCC. Gene Ontology (GO) analysis indicated significant enrichment of mitophagy pathways in cluster A. Functional investigations demonstrated that PINK1-overexpressing cells exhibited increased sensitivity to sunitinib (lower IC50 values), whereas PINK1 knockdown conferred therapeutic resistance. Western blot and immunofluorescence analyses confirmed elevated mitophagy levels in PINK1-overexpressing cells under sunitinib treatment, contrasting with diminished mitophagy in PINK1-deficient cells.

Our findings advance the understanding of mitochondrial dynamics in ccRCC progression, demonstrating that PINK1-mediated enhancement of mitophagy critically potentiates the anti-tumor effects of sunitinib in ccRCC.

Oral squamous cell carcinoma is the most prevalent of all the oral cancers. There is no definitive marker available for its early diagnosis and its effective prognosis. YAP serves as a transcriptional regulator in hippo tumor suppressor pathway thereby activating the transcription of genes taking part in cellular proliferation, alteration, migration, and invasion. On the contrary, PARK2 acts as a tumor suppressor and has been widely explored in various malignancies. However, its role in OSCC carcinogenesis is untrodden.

To evaluate the Immunohistochemical expression of YAP and PARK2 in oral epithelial dysplasia and Oral Squamous Cell Carcinoma and establish them as prognostic markers.

The study sample consisted of 70 formalin fixed paraffin embedded tissue sections of normal oral mucosa (10), oral epithelial dysplasia (30) and oral squamous cell carcinoma (30). Immunohistochemical analysis of YAP and PARK2 was done and final scores were calculated. Further, the markers were graded as low and high expression groups. Statistical analysis was done using chi-square test, cox regression analysis and Spearman's correlation. Kaplan Meier plot for survival analysis was also plotted.

Immunohistochemical expression of YAP depicted a gradual incline from normal oral mucosa to oral squamous cell carcinoma while PARK2 showed a reverse trend. Significant difference of YAP and PARK2 expression between three groups was noted. Inverse moderate degree of correlation was observed between both the markers in OSCC group.

Concomitant immunoexpression of YAP and PARK2 with a moderate degree of inverse correlation from normal oral mucosa to oral squamous cell carcinoma could probably serve as diagnostic and prognostic markers as they might act through a common mechanism, probably hippo/YAP signaling, which could be further confirmed by larger sample size, including longer follow up in future studies.

Mitochondria are indispensable in cells and play crucial roles in maintaining cellular homeostasis, energy production, and regulating cell death. Mitochondrial dysfunction has various manifestations, causing different diseases by affecting the diverse functions of mitochondria in the body. Previous studies have mainly focused on mitochondrial-related diseases caused by nuclear gene mutations or mitochondrial gene mutations, or mitochondrial dysfunction resulting from epigenetic regulation, such as DNA and histone modification. In recent years, as a popular research area, m6A has been involved in a variety of important processes under physiological and pathological conditions. However, there are few summaries on how RNA methylation, especially m6A RNA methylation, affects mitochondrial function. Additionally, the role of m6A in pathology through influencing mitochondrial function may provide us with a new perspective on disease treatment. In this review, we summarize several manifestations of mitochondrial dysfunction and compile examples from recent years of how m6A affects mitochondrial function and its role in some diseases.

Mitochondria serve as the primary source of intracellular reactive oxygen species (ROS), which play a critical role in orchestrating cell death pathways such as pyroptosis in various types of cancers. PINK1-mediated mitophagy effectively removes damaged mitochondria and reduces detrimental ROS levels, thereby promoting cell survival. However, the regulation of pyroptosis by PINK1 and ROS in neuroblastoma remains unclear. In this study, we demonstrate that inhibition or deficiency of PINK1 sensitizes ROS signaling and promotes pyroptosis in neuroblastoma cells via the BAX-caspase-GSDME signaling pathway. Specifically, inhibition of PINK1 by AC220 or knockout of PINK1 impairs mitophagy and enhances ROS production, leading to oxidation and oligomerization of TOMM20, followed by mitochondrial recruitment and activation of BAX. Activated BAX facilitates the release of CYCS (cytochrome c, somatic) from the mitochondria into the cytosol, activating CASP3 (caspase 3). Subsequently, activated CASP3 cleaves and activates GSDME, inducing pyroptosis. Furthermore, inhibition or deficiency of PINK1 potentiates the anti-tumor effects of the clinical ROS-inducing drug ethacrynic acid (EA) to inhibit neuroblastoma progression in vivo. Therefore, our study provides a promising intervention strategy for neuroblastoma through the induction of pyroptosis.Abbreviation: AC220, quizartinib; ANOVA, analysis of variance; ANXA5, annexin A5; BAX, BCL2 associated X, apoptosis regulator; BAK1, BCL2 antagonist/killer 1; CCCP, carbonyl cyanide m-chlorophenyl hydrazone; COX4/COX IV, cytochrome c oxidase subunit 4; CS, citrate synthase; CSC, cancer stem cell; CYCS, cytochrome c, somatic; DTT, dithiothreitol; DNA, deoxyribonucleic acid; EA, ethacrynic acid; Fer-1, ferroptosis inhibitor ferrostatin-1; FLT3, fms related tyrosine kinase 3; GSDMD, gasdermin D; GSDME, gasdermin E; kDa, kilodalton; LDH, lactate dehydrogenase; MFN1, mitofusin 1; MFN2, mitofusin 2; mito, mitochondria; mito-ROS, mitochondrial ROS; mtKeima, mitochondria-targeted monomeric keima-red; ml, microliter; MT-CO2, mitochondrially encoded cytochrome c oxidase II; NAC, antioxidant N-acetyl-L-cysteine; Nec-1, necroptosis inhibitor necrostatin-1; OMA1, OMA1 zinc metallopeptidase; OMM, outer mitochondrial membrane; PARP, poly(ADP-ribose) polymerase; PBS, phosphate-buffered saline; PI, propidium iodide; PINK1, PTEN induced kinase 1; PRKN/Parkin, parkin RBR E3 ubiquitin protein ligase; Q-VD, Q-VD-OPH; ROS, reactive oxygen species; sg, single guide; sh, short hairpin; STS, staurosporine; TOMM20, translocase of outer mitochondrial membrane 20; TIMM23, translocase of inner mitochondrial membrane 23; μm, micrometer; μM, micromolar.

Mitophagy, the process by which cells eliminate damaged mitochondria, is mediated by PINK1 (PTEN induced kinase 1). Our recent research indicates that PINK1 functions as a tumor suppressor in colorectal cancer by regulating cellular metabolism. Interestingly, PINK1 ablation activated the NLRP3 (NLR family pyrin domain containing 3) inflammasome, releasing IL1B (interleukin 1 beta). However, inhibiting the NLRP3-IL1B signaling pathway with an IL1R (interleukin 1 receptor) antagonist or NLRP3 inhibitor did not hinder colon tumor growth after PINK1 loss. To identify druggable targets in PINK1-deficient tumors, ribonucleic acid sequencing analysis was performed on colon tumors from pink1 knockout and wild-type mice. Gene Set Enrichment Analysis highlighted the enrichment of iron ion transmembrane transporter activity. Subsequent qualitative polymerase chain reaction and western blot analysis revealed an increase in mitochondrial iron transporters, including mitochondrial calcium uniporter, in PINK1-deficient colon tumor cells and tissues. Live-cell iron staining demonstrated elevated cellular and mitochondrial iron levels in PINK1-deficient cells. Clinically used drugs deferiprone and minocycline reduced mitochondrial iron and superoxide levels, resulting in decreased colon tumor cell growth in vitro and in vivo. Manipulating the mitochondrial iron uptake protein MCU (mitochondrial calcium uniporter) also affected cell and xenograft tumor growth. This study suggests that therapies aimed at reducing mitochondrial iron levels may effectively inhibit colon tumor growth, particularly in patients with low PINK1 expression.Abbreviation: ANOVA: analysis of variance; APC: adenomatous polyposis coli; cAMP: cyclic adenosine monophosphate; CDX2: caudal type homeobox 2; CGAS: cyclic GMP-AMP synthase; CRC: colorectal cancer; DNA: deoxyribonucleic acid; DFP: deferiprone; DMEM: Dulbecco's modified Eagle medium; DSS: dextran sodium sulfate; ERT2-Cre: Cre recombinase fused to a triple mutant form of the human estrogen receptor; EV: empty vector; GLB: glybenclamide/glyburide; H&E: hematoxylin and eosin; ICP-MS: inductively coupled plasma mass spectrometer; IL1B: interleukin 1 beta; kDa: kilodalton; MCU: mitochondrial calcium uniporter; MKI67: marker of proliferation Ki-67; mRNA: messenger ribonucleic acid; MTT: 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide; NLRP3: NLR family pyrin domain containing 3; OE: overexpression; PBS: phosphate-buffered saline; p-CREB: phosphorylated cAMP responsive element binding protein; PINK1: PTEN induced kinase 1; p-PRKAA/AMPK: phosphorylated protein kinase AMP-activated catalytic subunit alpha; qPCR: qualitative polymerase chain reaction; RNA-seq: ribonucleic acid sequencing; ROS: reactive oxygen species; sg: single guide; sh: short hairpin; SLC25A28: solute carrier family 25 member 28; SLC25A37/MFRN: solute carrier family 25 member 37; STING1: stimulator of interferon response cGAMP interactor 1; TP53/p53: tumor protein p53; TUBA: tubulin alpha; µL: microliter; µm: micrometer; µM: micromolar; mm: millimeter.

Ferroptosis is a novel, iron-dependent regulated cell death mode. The biochemical features of ferroptosis include iron accumulation, lipid peroxidation, inhibition of glutathione peroxidase 4 (GPX4) and antioxidant glutathione (GSH) decrease through inhibition of the system xc- transporter. Zinc finger NFX1 type-containing 1 (ZNFX1) antisense RNA 1 (ZFAS1) is a long non-coding RNA that has been identified as an oncogene in various types of cancers. However, its regulatory role and molecular mechanisms in clear cell renal cell carcinoma (ccRCC) ferroptosis remain unclear. In this study, the ferroptosis inducers (FINS) (erastin and RSL3) were found to increase ZFAS1 expression through the facilitation of SP1 binding to the ZFAS1 promoter. ZFAS1 increased mRNA and protein levels of solute carrier family 25 member 28 (SLC25A28) via functioning as a miR-185-5p sponge. Overexpressed SLC25A28 increased the production of ROS and caused a decrease in NADPH and GSH in cells treated with FINS. In addition, overexpression of ZFAS1 enhanced ferroptosis both in vitro and in vivo. Altogether, this study demonstrates that ZFAS1 is a crucial element of ferroptosis in ccRCC, as it is responsible for the regulation of miR-185-5p and SLC25A28. Introducing ferroptosis could be a beneficial approach to treat ccRCC patients with high ZFAS1 levels.

Osteosarcoma (OS), the most prevalent primary malignant bone tumor, is characterized by a poor prognosis and high metastatic potential. Mitochondrial autophagy has been implicated in cancer suppression. This study aimed to identify prognostic genes associated with mitochondrial autophagy in OS. Public datasets, including TARGET-OS, GSE99671, and GSE21257, were retrieved for analysis. Differentially expressed genes (DEGs1) between OS and normal samples were identified from GSE99671. Single-sample Gene Set Enrichment Analysis (ssGSEA) was applied to quantify the enrichment scores of 29 mitochondrial autophagy-related genes (MARGs) in OS samples from TARGET-OS, categorizing them into high- and low-score groups to extract DEGs2. The intersection of DEGs1 and DEGs2 yielded mitochondrial autophagy-associated differentially expressed genes (MDGs). Prognostic genes were subsequently screened through a multi-step regression analysis, and a risk score was computed. TARGET-OS samples were stratified into high- and low-risk groups based on the optimal cutoff value of the risk score. GSEA was conducted between the two risk groups. Additionally, associations between prognostic genes and the immune microenvironment were explored. A total of 31 MDGs were identified from the overlap of 3,207 DEGs1 and 622 DEGs2. Five prognostic genes-KLK2, NRXN1, HES5, OR2W3, and HS3ST4-were further selected. Kaplan-Meier survival analysis indicated significantly reduced survival in the high-risk group. GSEA revealed enrichment in ABC transporter activity and glycolysis/gluconeogenesis pathways. Immunoanalysis demonstrated significant differences in 11 immune cell populations and three immune functions between risk groups, notably myeloid-derived suppressor cells (MDSCs) and Type 1 T helper cells. HS3ST4 exhibited the strongest positive correlation with macrophages, whereas NRXN1 showed the most pronounced negative correlation with memory B cells. Expressions of HAVCR2 and PDCD1LG2 were elevated in the low-risk group. Functional analysis indicated significant differences in dysfunction patterns between risk groups. This study identified five mitochondrial autophagy-related prognostic genes and constructed a risk model, offering novel insights into OS diagnosis and therapeutic strategies.

The constrained cross-talk between myeloid cells and T cells in the tumor immune microenvironment (TIME) restricts cancer immunotherapy efficacy, whereas the underlying mechanism remains elusive. Parkin, an E3 ubiquitin ligase renowned for mitochondrial quality control, has emerged as a regulator of immune response. Here, we show that both systemic and macrophage-specific ablations of Parkin in mice lead to attenuated tumor progression and prolonged mouse survival. By single-cell RNA-seq and flow cytometry, we demonstrate that Parkin deficiency reshapes the TIME through activating both innate and adaptive immunities to control tumor progression and recurrence. Mechanistically, Parkin activation by AMP-activated protein kinase rather than PTEN-induced kinase 1 mediated major histocompatibility complex I down-regulation on macrophages via Autophagy related 5-dependent autophagy. Furthermore, Parkin deletion synergizes with immune checkpoint blockade treatment and Park2-/- signature aids in predicting the prognosis of patients with solid tumor. Our findings uncover Parkin's involvement in suppressing macrophage antigen presentation for coordinating the cross-talk between macrophages and T cells.

Mitochondrial homeostasis (MH) refers to the dynamic balance of mitochondrial number, function, and quality within cells. Maintaining MH is significant in the occurrence, development, and clinical treatment of Gastrointestinal (GI) tumors. Ubiquitination, as an important post-translational modification mechanism of proteins, plays a central role in the regulation of MH. Over the past decade, research on the regulation of MH by ubiquitination has focused on mitochondrial biogenesis, mitochondrial dynamics, Mitophagy, and mitochondrial metabolism during these processes. This review summarizes the mechanism and potential therapeutic targets of ubiquitin (Ub)-regulated MH intervention in GI tumors.

Hepatocellular carcinoma (HCC) is a globally prevalent disease. Our article evaluates risk models based on autophagy- and HCC-related genes and their prognostic value by bioinformatics analytical methods to provide a scientific basis for clinical treatment.

Prognostic genes were identified by univariate and multivariate Cox analyses, and risk scores were calculated. The value of risk models was analysed by receiver operating characteristic curve (ROC), immune microenvironment and drug sensitivity. Prognostic gene-related regulatory mechanisms based on network database.

We screened four prognosis-related genes (SQSTM1, GABARAPL1, CDKN2A, HSPB8) for model construction. The AUC for 1-, 2- and 3-year survival was higher than 0.6 in both the training and validation sets. The nomogram constructed based on risk scores, pathologic_T predicted the outcome better. There were differences in the tumour microenvironment between the high and low risk groups, as evidenced by differences in the distribution of immune cells and differences in the expression of immune checkpoints.

Our results illustrate that models, nomograms and risk scores were valuable for tumour progression.

Not applicable.

As one part of the innate immune response to external stimuli, chronic inflammation increases the risk of various cancers, and tumor-promoting inflammation is considered one of the enabling characteristics of cancer development. Recently, there has been growing evidence on the role of anti-inflammation therapy in cancer prevention and treatment. And researchers have already achieved several noteworthy outcomes. In the review, we explored the underlying mechanisms by which inflammation affects the occurrence and development of cancer. The pro- or anti-tumor effects of these inflammatory factors such as interleukin, interferon, chemokine, inflammasome, and extracellular matrix are discussed. Since FDA-approved anti-inflammation drugs like aspirin show obvious anti-tumor effects, these drugs have unique advantages due to their relatively fewer side effects with long-term use compared to chemotherapy drugs. The characteristics make them promising candidates for cancer chemoprevention. Overall, this review discusses the role of these inflammatory molecules in carcinogenesis of cancer and new inflammation molecules-directed therapeutic opportunities, ranging from cytokine inhibitors/agonists, inflammasome inhibitors, some inhibitors that have already been or are expected to be applied in clinical practice, as well as recent discoveries of the anti-tumor effect of non-steroidal anti-inflammatory drugs and steroidal anti-inflammatory drugs. The advantages and disadvantages of their application in cancer chemoprevention are also discussed.

Absent in melanoma 2 (AIM2) is a member of the innate immune sensors that recognizes cytosolic nucleic acids, leading to inflammasome assembly. In recent years, several studies in the oncology field have highlighted the presence of cytoplasmic double-stranded DNA (dsDNA) following necrosis and/or genomic instability, which is typical of malignant transformation. The recognition of dsDNA by the AIM2 inflammasome either in cancer cells or in immune cells can further exacerbate inflammatory processes on the basis of cancer progression. In this context, the role of AIM2 in cancer is still controversial in that some authors assume that AIM2 activation has pro-tumor activities, while others define it as anti-tumor. This discrepancy may be due to the nature of the cells where AIM2 is expressed or the histology of the tumor. This review aims to provide an overview of the controversial role of AIM2 in cancer, taking into consideration the pharmacological tools currently available to modulate AIM2 activity in cancer.

Cellular metabolism plays a pivotal role in the development and progression of pancreatic ductal adenocarcinoma (PDAC), with dysregulated metabolic pathways contributing to tumorigenesis and therapeutic resistance. Distinct metabolic heterogeneity in pancreatic cancer significantly impacts patient prognosis, as variations in metabolic profiles influence tumor behavior and treatment responses.

This review explores the intricate interplay between mitochondrial dynamics, mitophagy, and cellular metabolism in PDAC. We discuss the significance of mitophagy dysregulation in PDAC pathogenesis, emphasizing its influence on treatment responses and prognosis. Furthermore, we analyze the impact of mitochondrial dynamics alterations, including fission and fusion processes, on PDAC progression and tumorigenesis.

Targeting mitochondrial metabolism holds promise for advancing PDAC therapeutics. Ongoing clinical trials underscore the therapeutic potential of modulating key regulators of mitochondrial dynamics and mitophagy. Despite inherent challenges, these approaches offer diverse strategies to enhance treatment efficacy and improve patient outcomes.

Aberrations emerging in mitochondrial homeostasis are restrained by mitophagy to control mitochondrial integrity, bioenergetics signaling, metabolism, oxidative stress, and apoptosis. The mitophagy-accompanied mitochondrial processes that occur in a dysregulated condition act as drivers for cancer occurrence. In addition, the enigmatic nature of mitophagy in cancer cells modulates the cellular proteome, creating challenges for therapeutic interventions. Several reports found the role of cellular signaling pathways in cancer to modulate mitophagy to mitigate stress, immune checkpoints, energy demand, and cell death. Thus, targeting mitophagy to hinder oncogenic intracellular signaling by promoting apoptosis, in hindsight, might have an edge against cancer. This review highlights the receptors and adaptors, and the involvement of many proteins in mitophagy and their role in oncogenesis. It also provides insight into using mitophagy as a potential target for therapeutic intervention in various cancer types.

Uncontrollable cancer cell growth is characterized by the maintenance of cellular homeostasis through the continuous accumulation of misfolded proteins and damaged organelles. This review delineates the roles of two complementary and synergistic degradation systems, the ubiquitin-proteasome system (UPS) and the autophagy-lysosome system, in the degradation of misfolded proteins and damaged organelles for intracellular recycling. We emphasize the interconnected decision-making processes of degradation systems in maintaining cellular homeostasis, such as the biophysical state of substrates, receptor oligomerization potentials (e.g., p62), and compartmentalization capacities (e.g., membrane structures). Mitochondria, the cellular hubs for respiration and metabolism, are implicated in tumorigenesis. In the subsequent sections, we thoroughly examine the mechanisms of mitochondrial quality control (MQC) in preserving mitochondrial homeostasis in human cells. Notably, we explored the relationships between mitochondrial dynamics (fusion and fission) and various MQC processes-including the UPS, mitochondrial proteases, and mitophagy-in the context of mitochondrial repair and degradation pathways. Finally, we assessed the potential of targeting MQC (including UPS, mitochondrial molecular chaperones, mitochondrial proteases, mitochondrial dynamics, mitophagy and mitochondrial biogenesis) as cancer therapeutic strategies. Understanding the mechanisms underlying mitochondrial homeostasis may offer novel insights for future cancer therapies.

Parkin-mediated mitophagy is essential for clearing damaged mitochondria, and it inhibits tumour development. The role of mitophagy in modulating tumour immunity is becoming clearer, but the underlying mechanism is still poorly understood.

This study was designed to examine the role of Parkin in the immune microenvironment of liver tumours induced by carbon tetrachloride (CCl4).

Single-cell RNA sequencing analysis, Western blot, immunofluorescence and co-immunoprecipitation were used to verify the mechanism of Parkin affecting the tumour microenvironment by altering the expression of PD-1.

Our data revealed that Park2-/- mice showed severe liver damage and increased malignancy. Single-cell RNA sequencing analysis of T lymphocytes in liver tumours showed that the number of cytotoxic CD8+ T cells (Gzmb/Ifng/Fasl) was significantly decreased and the number of exhausted CD8+ T cells (Pdcd1/Lag3/Tigit/Havcr2/Ctla4) was significantly increased in Park2-/- mice, indicating the immune suppressive microenvironment. Single-cell RNA sequencing analysis of myeloid-derived cells also displayed the increase of M2-like macrophages in Park2-/- mice. Through quantitative proteomic analysis, it was found that the differential protein expression between the two groups mainly localized in the plasma membrane and extracellular, including PD-1, MHC-Ⅰ molecules etc., and was mainly associated with PD-1 and antigen presentation pathways. It could impair the antitumour immune response with Parkin deficiency. Parkin deficiency leads to the decrease of hepatic mitophagy levels and the formation of an immune suppressive microenvironment, which promotes the tumourigenesis of liver cancer.

As an E3 ubiquitin ligase, Parkin induces the ubiquitination and degradation of PD-1 in liver cancer and could influence antitumour immunity through the PD-1/PD-L1 signalling pathway. Thus, remodeling the tumour microenvironment through the reintroduction of Parkin or enhancement of mitophagy could activate the anti-tumour immune response and improve the immunotherapy efficacy, which may be a promising strategy for the treatment of HCC.

Most spheroid models use size measurements as a primary readout parameter; some models extend analysis to T cell infiltration or perform caspase activation assays. However, to our knowledge, T cell motility analysis is not regularly included as an endpoint in imaging studies on cancer spheroids.

Here, we intend to demonstrate that motility analysis of macrophages and T cells is a valuable functional endpoint for studies on molecular interventions in the tumor microenvironment. In particular, T cell migration analysis represents the final step of effector function, as T cells engage with targets cells upon cytotoxic interaction, which is represented by an arrest within the spheroid volume. Therefore, T cell arrest is a novel readout parameter of T cell effector function in spheroids.

Here, we demonstrate that incubation of macrophages with nigericin for NLRP3 activation increases T cell velocity, but results in decreased T cellular arrest. This is paralleled by reduced rejection kinetics of pancreatic cancer spheroids in the presence of antigen-dependent T cells and nigericin-treated macrophages. Our model demonstrates consistent changes in T cell motility upon coculturing of T cells and tumors cells with macrophages, including influences of molecular interventions such as NLRP3 activation.

Motility analysis using a spheroid model of pancreatic cancer is a more sophisticated alternative to in vitro cytotoxicity assays measuring spheroid size. Ultimately, an optimized spheroid model might replace at least some aspects of animal experiments investigating T cell effector function.

Cancer cells undergo remarkable metabolic changes to meet their high energetic and biosynthetic demands. The Warburg effect is the most well-characterized metabolic alteration, driving cancer cells to catabolize glucose through aerobic glycolysis to promote proliferation. Another prominent metabolic hallmark of cancer cells is their increased reliance on glutamine to replenish tricarboxylic acid (TCA) cycle intermediates essential for ATP production, aspartate and fatty acid synthesis, and maintaining redox homeostasis. In this context, mitochondria, which are primarily used to maintain energy homeostasis and support balanced biosynthesis in normal cells, become central organelles for fulfilling the heightened biosynthetic and energetic demands of proliferating cancer cells. Mitochondrial coordination and metabolite exchange with other cellular compartments are crucial. The human SLC25 mitochondrial carrier family, comprising 53 members, plays a pivotal role in transporting TCA intermediates, amino acids, vitamins, nucleotides, and cofactors across the inner mitochondrial membrane, thereby facilitating this cross-talk. Numerous studies have demonstrated that mitochondrial carriers are altered in cancer cells, actively contributing to tumorigenesis. This review comprehensively discusses the role of SLC25 carriers in cancer pathogenesis and metabolic reprogramming based on current experimental evidence. It also highlights the research gaps that need to be addressed in future studies. Understanding the involvement of these carriers in tumorigenesis may provide valuable novel targets for drug development.

Mitochondria are central actors in diverse physiological phenomena ranging from energy metabolism to stress signaling and immune modulation. Accumulating scientific evidence points to the critical involvement of specific mitochondrial-associated events, including mitochondrial quality control, intercellular mitochondrial transfer, and mitochondrial genetics, in potentiating the metastatic cascade of neoplastic cells. Furthermore, numerous recent studies have consistently emphasized the highly significant role mitochondria play in coordinating the regulation of tumor-infiltrating immune cells and immunotherapeutic interventions. This review provides a comprehensive and rigorous scholarly investigation of this subject matter, exploring the intricate mechanisms by which mitochondria contribute to tumor metastasis and examining the progress of mitochondria-targeted cancer therapies.

Diabetic retinopathy (DR), as one of the most common and significant microvascular complications of diabetes mellitus (DM), continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the understanding of its pathogenic mechanisms from perspectives such as inflammation and oxidative stress. Recent studies have indicated that characteristic neuroglial degeneration induced by DM occurs before the onset of apparent microvascular lesions. In order to comprehensively grasp the early-stage pathological changes of DR, the retinal neurovascular unit (NVU) will become a crucial focal point for future research into the occurrence and progression of DR. Based on existing evidence, ferroptosis, a form of cell death regulated by processes like ferritinophagy and chaperone-mediated autophagy, mediates apoptosis in retinal NVU components, including pericytes and ganglion cells. Autophagy-dependent ferroptosis-related factors, including BECN1 and FABP4, may serve as both biomarkers for DR occurrence and development and potentially crucial targets for future effective DR treatments. The aforementioned findings present novel perspectives for comprehending the mechanisms underlying the early-stage pathological alterations in DR and open up innovative avenues for investigating supplementary therapeutic strategies.

Dysregulated activation of the innate immune system is a critical driver of chronic inflammation that is associated with at least 30% of all cancers. Innate immunity can also exert tumour-promoting effects (e.g. proliferation) directly on cancer cells in an intrinsic manner. Conversely, innate immunity can influence adaptive immunity-based anti-tumour immune responses via Ag-presenting dendritic cells that activate natural killer and cytotoxic T cells to eradicate tumours. While adaptive anti-tumour immunity has underpinned immunotherapy approaches with immune checkpoint inhibitors and chimeric Ag receptor-T cells, the clinical utility of innate immunity in cancer is underexplored. Innate immune responses are governed by pattern recognition receptors, which comprise several families, including Toll-like, nucleotide-binding oligomerization domain-containing (NOD)-like and absent-in-melanoma 2 (AIM2)-like receptors. Notably, a subset of NOD-like and AIM2-like receptors can form large multiprotein "inflammasome" complexes which control maturation of biologically active IL-1β and IL-18 cytokines. Over the last decade, it has emerged that inflammasomes can coordinate contrasting pro- and anti-tumour responses in cancer and non-cancer (e.g. immune, stromal) cells. Considering the importance of inflammasomes to the net output of innate immune responses, here we provide an overview and discuss recent advancements on the diverse role of inflammasomes in cancer that have underpinned their potential targeting in diverse malignancies.

Mitochondrial autophagy (mitophagy) is very important process for the maintenance of cellular homeostasis, functionality and survival. Its dysregulation is associated with high risk and progression numerous serious diseases (e.g., oncological, neurodegenerative and cardiovascular ones). Therefore, targeting mitophagy mechanisms is very hot topic in the biological and medicinal research. The interrelationships between the regulation of mitophagy and iron homeostasis are now becoming apparent. In short, mitochondria are central point for the regulation of iron homeostasis, but change in intracellular cheatable iron level can induce/repress mitophagy. In this review, relationships between iron homeostasis and mitophagy are thoroughly discussed and described. Also, therapeutic applicability of mitophagy chelators in the context of individual diseases is comprehensively and critically evaluated.

Cancer cells preferentially utilize glycolysis for energy production, and GAPDH is a critical enzyme in glycolysis. Parkin is a tumor suppressor and a key protein involved in mitophagy regulation. However, the tumor suppression mechanism of Parkin has still not been elucidated. In this study, we identified mitochondrial GAPDH as a new substrate of the E3 ubiquitin ligase Parkin, which mediated GAPDH ubiquitination in human cervical cancer. The translocation of GAPDH into mitochondria was driven by the PINK1 kinase, and either PINK1 or GAPDH mutation prevented the accumulation of GAPDH in mitochondria. Parkin caused the ubiquitination of GAPDH at multiple sites (K186, K215, and K219) located within the enzyme-catalyzed binding domain of the GAPDH protein. GAPDH ubiquitination was required for mitophagy, and stimulation of mitophagy suppressed cervical cancer cell growth, indicating that mitophagy serves as a type of cell death. Mechanistically, PHB2 served as a key mediator in GAPDH ubiquitination-induced mitophagy through stabilizing PINK1 protein and GAPDH mutation resulted in the reduced distribution of PHB2 in mitophagic vacuole. In addition, ubiquitination of GAPDH decreased its phosphorylation level and enzyme activity and inhibited the glycolytic pathway in cervical cancer cells. The results of in vivo experiments also showed that the GAPDH mutation increased glycolysis in cervical cancer cells and accelerated tumorigenesis. Thus, we concluded that Parkin may exert its anticancer function by ubiquitinating GAPDH in mitochondria. Taken together, our study further clarified the molecular mechanism of tumor suppression by Parkin through the regulation of energy metabolism, which provides an experimental basis for the development of new drugs for the treatment of human cervical cancer.

High mobility group box 1 (HMGB1) and indoleamino-2, 3-dioxygenase (IDO) participate in the occurrence and development of esophageal squamous cell carcinoma (ESCC), regulate the tumor immune microenvironment, and are closely related to tumor growth and metastasis. However, the regulatory mechanism of serum HMGB1 and IDO has not been clarified and needs further exploration.

Blood samples of 55 ESCC patients initially hospitalized in the Fourth Hospital of Hebei Medical University from August 2021 to January 2022 were selected as the ESCC group, and relevant clinical data were collected, and blood samples from 40 healthy people during the same period were selected as the control group. Serum HMGB1 and IDO levels were determined by ELISA, and lymphocyte subsets in peripheral blood of all subjects were detected by flow cytometry. The correlation between the expression levels of HMGB1 and IDO in ESCC cells was detected by Western blot.

Serum HMGB1 and IDO levels were significantly increased in ESCC patients, and with the progression of ESCC patients, serum HMGB1 and IDO levels were also gradually increased; serum HMGB1 was significantly correlated with IDO; serum HMGB1 and IDO combined with CEA and SCC-Ag were of high value in predicting the clinical progression of ESCC patients; the absolute counts of CD4+CD28+T cells and CD8+CD28+T cells in high HMGB1 group were significantly lower than those in low HMGB1 group, while the percentage of CD4+PD-1+T cells was significantly higher than that in low HMGB1 group; the percentage and absolute counts of CD4+CD28+T cells and the absolute counts of CD8+CD28+T cells in high IDO group were significantly lower than those in the low IDO group, while the percentage of CD8+PD-1+T cells was significantly higher than that in the low IDO group; increased serum HMGB1 and IDO expression levels were closely related to poor prognosis in ESCC patients; and HMGB1 may promote IDO expression by activating NF-κB signaling pathway.

Serum HMGB1 and IDO have a synergistic effect, they inhibit immune function and promote tumor progression in ESCC patients, and also lead to poor prognosis.

The complex relationship between mitochondrial dynamics and autophagy illustrates how two cellular housekeeping processes are intimately linked, illuminating fundamental principles of cellular homeostasis and shedding light on disparate pathological conditions including several neurodegenerative disorders. Here we review the basic tenets of mitochondrial dynamics i.e., the concerted balance between fusion and fission of the organelle, and its interplay with macroautophagy and selective mitochondrial autophagy, also dubbed mitophagy, in the maintenance of mitochondrial quality control and ultimately in cell viability. We illustrate how conditions of altered mitochondrial dynamics reverberate on autophagy and vice versa. Finally, we illustrate how altered interplay between these two key cellular processes participates in the pathogenesis of human disorders affecting multiple organs and systems.

Macroautophagy/autophagy is primarily accountable for the degradation of damaged organelles and toxic macromolecules in the cells. Regarding the essential function of autophagy for preserving cellular homeostasis, changes in, or dysfunction of, autophagy flux can lead to disease development. In the current paper, the complicated function of autophagy in aging-associated pathologies and cancer is evaluated, highlighting the underlying molecular mechanisms that can affect longevity and disease pathogenesis. As a natural biological process, a reduction in autophagy is observed with aging, resulting in an accumulation of cell damage and the development of different diseases, including neurological disorders, cardiovascular diseases, and cancer. The MTOR, AMPK, and ATG proteins demonstrate changes during aging, and they are promising therapeutic targets. Insulin/IGF1, TOR, PKA, AKT/PKB, caloric restriction and mitochondrial respiration are vital for lifespan regulation and can modulate or have an interaction with autophagy. The specific types of autophagy, such as mitophagy that degrades mitochondria, can regulate aging by affecting these organelles and eliminating those mitochondria with genomic mutations. Autophagy and its specific types contribute to the regulation of carcinogenesis and they are able to dually enhance or decrease cancer progression. Cancer hallmarks, including proliferation, metastasis, therapy resistance and immune reactions, are tightly regulated by autophagy, supporting the conclusion that autophagy is a promising target in cancer therapy.

The activation of innate immunity and associated interferon (IFN) signaling have been implicated in cancer, but the regulators are elusive and links to tumor suppression remain undetermined. Here, we found that Parkin, an E3 ubiquitin ligase altered in Parkinson's Disease, was epigenetically silenced in cancer and its reexpression by clinically approved demethylating therapy stimulated transcription of a potent IFN response in tumor cells. This pathway required Parkin E3 ubiquitin ligase activity, involved the subcellular trafficking and release of the alarmin High Mobility Group Box 1 (HMGB1) and was associated with inhibition of NF-κB gene expression. In turn, Parkin-expressing cells released an IFN secretome that upregulated effector and cytotoxic CD8+ T cell markers, lowered the expression of immune inhibitory receptors TIM3 and LAG3, and stimulated high content of the self renewal/stem cell factor, TCF1. PRKN-induced CD8+ T cells selectively accumulated in the microenvironment and inhibited transgenic and syngeneic tumor growth in vivo. Therefore, Parkin is an epigenetically regulated activator of innate immunity and dual mode tumor suppressor, inhibiting intrinsic tumor traits of metabolism and cell invasion, while simultaneously reinvigorating CD8 T cell functions in the microenvironment.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive solid malignancy with low 5-year survival and limited treatment options. We conducted an unbiased screening using FDA-approved drug and demonstrated that cetylpyridinium chloride (CPC), a component commonly found in mouthwash and known for its robust bactericidal and antifungal attributes, exhibits anticancer activity against human PDAC cells. CPC inhibited PDAC cell growth and proliferation by inducing paraptosis, rather than apoptosis. Mechanistically, CPC induced paraptosis through the initiation of endoplasmic reticulum stress, leading to the accumulation of misfolded proteins. Subsequently, the endoplasmic reticulum stress to nucleus signaling 1 (ERN1)-mitogen-activated protein kinase kinase kinase 5 (MAP3K5)-p38 mitogen-activated protein kinase (MAPK) signaling pathway was activated, ultimately culminating in the induction of paraptosis. In vivo experiments, including those involving patient-derived xenografts, orthotopic models, and genetically engineered mouse models of PDAC, provided further evidence of CPC's effectiveness in suppressing the growth of pancreatic tumors.

Cancer stem cells represent a resilient subset within the tumor microenvironment capable of differentiation, regeneration, and resistance to chemotherapeutic agents, often using dormancy as a shield. Their unique properties, including drug resistance and metastatic potential, pose challenges for effective targeting. These cells exploit certain metabolic processes for their maintenance and survival. One of these processes is autophagy, which generally helps in energy homeostasis but when hijacked by CSCs can help maintain their stemness. Thus, it is often referred as an Achilles heel in CSCs, as certain cancers tend to depend on autophagy for survival. Autophagy, while crucial for maintaining stemness in cancer stem cells (CSCs), can also serve as a vulnerability in certain contexts, making it a complex target for therapy. Regulators of autophagy like AMPK (5' adenosine monophosphate-activated protein kinase) also play a crucial role in maintaining CSCs stemness by helping CSCs in metabolic reprogramming in harsh environments. The purpose of this review is to elucidate the interplay between autophagy and AMPK in CSCs, highlighting the challenges in targeting autophagy and discussing therapeutic strategies to overcome these limitations. This review focuses on previous research on autophagy and its regulators in cancer biology, particularly in CSCs, addresses the remaining unanswered questions, and potential targets for therapy are also brought to attention.

ATPase family AAA domain containing protein 3, commonly known as ATAD3 is a versatile mitochondrial protein that is involved in a large number of pathways. ATAD3 is a transmembrane protein that spans both the inner mitochondrial membrane and outer mitochondrial membrane. It, therefore, functions as a connecting link between the mitochondrial lumen and endoplasmic reticulum facilitating their cross-talk. ATAD3 contains an N-terminal domain which is amphipathic in nature and is inserted into the membranous space of the mitochondria, while the C-terminal domain is present towards the lumen of the mitochondria and contains the ATPase domain. ATAD3 is known to be involved in mitochondrial biogenesis, cholesterol transport, hormone synthesis, apoptosis and several other pathways. It has also been implicated to be involved in cancer and many neurological disorders making it an interesting target for extensive studies. This review aims to provide an updated comprehensive account of the role of ATAD3 in the mitochondria especially in lipid transport, mitochondrial-endoplasmic reticulum interactions, cancer and inhibition of mitophagy.

Metformin (MET), a type 2 diabetes treatment, has attracted increased attention for its potential antitumor properties; however, the precise mechanism underlying this activity remains unclear. Our previous in vivo and in vitro studies revealed MET's inhibitory effect on ovarian cancer, with the synergistic effects of MET and the MDM2 inhibitor RG7388 contributing to ovarian cancer treatment. This study further explores the mechanism underlying MET's inhibition of ovarian cancer.

Following MET treatment, we analyzed the differentially expressed proteins in ovarian cancer cells using a tandem mass tag (TMT)-based proteomic approach coupled with bioinformatics.

Using A2780 and SKOV3 ovarian cancer cells, we identified six upregulated and two downregulated proteins after MET treatment. Bioinformatics analysis revealed that these proteins predominately affect ovarian cancer cells by regulating iron ion transport, iron ion homeostasis, and mitochondrial and ribosomal functions. Validation via western blot confirmed MET-induced elevation of hydroxybutyrate dehydrogenase type 2 (BDH2) protein expression levels in A2780 and SKOV3 cells.

Overall, our findings suggest that combining MET with other metabolic drugs, such as iron-chelating agents and mitochondrial inhibitors, may result in synergistic antitumor effects, thereby offering novel avenues for ovarian cancer treatment development.

Preserving a functional mitochondrial network is crucial for cellular well-being, considering the pivotal role of mitochondria in ensuring cellular survival, especially under stressful conditions. Mitophagy, the selective removal of damaged mitochondria through autophagy, plays a pivotal role in preserving cellular homeostasis by preventing the production of harmful reactive oxygen species from dysfunctional mitochondria. While the involvement of mitophagy in neurodegenerative diseases has been thoroughly investigated, it is becoming increasingly evident that mitophagy plays a significant role in cancer biology. Perturbations in mitophagy pathways lead to suboptimal mitochondrial quality control, catalyzing various aspects of carcinogenesis, including establishing metabolic plasticity, stemness, metabolic reconfiguration of cancer-associated fibroblasts, and immunomodulation. While mitophagy performs a delicate balancing act at the intersection of cell survival and cell death, mounting evidence indicates that, particularly in the context of stress responses induced by cancer therapy, it predominantly promotes cell survival. Here, we showcase an overview of the current understanding of the role of mitophagy in cancer biology and its potential as a target for cancer therapy. Gaining a more comprehensive insight into the interaction between cancer therapy and mitophagy has the potential to reveal novel targets and pathways, paving the way for enhanced treatment strategies for therapy-resistant tumors in the near future.

Parkin (PARK2) deficiency is frequently observed in various cancers and potentially promotes tumor progression. Here, we showed that Parkin expression is downregulated in liver cancer tissues, which correlates with poor patient survival. Parkin deficiency in liver cancer cells promotes migration and metastasis as well as changes in EMT and metastasis markers. A negative correlation exists between TMEFF1 and Parkin expression in liver cancer cells and tumor tissues. Parkin deficiency leads to upregulation of TMEFF1 which promotes migration and metastasis. TMEFF1 transcription is activated by Parkin-induced endogenous TGF-β production and subsequent phosphorylation of Smad2/3 and its binding to TMEFF1 promotor. TGF-β inhibitor and TMEFF1 knockdown can reverse shParkin-induced cell migration and changes of EMT markers. Parkin interacts with and promotes the ubiquitin-dependent degradation of HIF-1α/HIF-1β and p53, which accounts for the suppression of TGF-β production. Our data have revealed that Parkin deficiency in cancer leads to the activation of the TGF-β/Smad2/3 pathway, resulting in the expression of TMEFF1 which promotes cell migration, EMT, and metastasis in liver cancer cells.

Mitophagy serves as a critical mechanism for tumor cell death, significantly impacting the progression of tumors and their treatment approaches. There are significant challenges in treating patients with head and neck squamous cell carcinoma, underscoring the importance of identifying new targets for therapy. The function of mitophagy in head and neck squamous carcinoma remains uncertain, thus investigating its impact on patient outcomes and immunotherapeutic responses is especially crucial. We initially analyzed the differential expression, prognostic value, intergene correlations, copy number variations, and mutation frequencies of mitophagy-related genes at the pan-cancer level. Through unsupervised clustering, we divided head and neck squamous carcinoma into three subtypes with distinct prognoses, identified the signaling pathway features of each subtype using ssGSEA, and characterized subtype B as having features of an immune desert using various immune infiltration calculation methods. Using multi-omics data, we identified the genomic variation characteristics, mutated gene pathway features, and drug sensitivity features of the mitophagy subtypes. Utilizing a combination of 10 machine learning algorithms, we have developed a prognostic scoring model called Mitophagy Subgroup Risk Score (MSRS), which is used to predict patient survival and the response to immune checkpoint blockade therapy. Simultaneously, we applied MSRS to single-cell analysis to explore intercellular communication. Through laboratory experiments, we validated the biological function of SLC26A9, one of the genes in the risk model. In summary, we have explored the significant role of mitophagy in head and neck tumors through multi-omics data, providing new directions for clinical treatment.

Ferroptosis, a nonapoptotic form of cell death characterized by iron accumulation and uncontrolled lipid peroxidation, holds promise as a therapeutic approach in cancer treatment, alongside established modalities, such as chemotherapy, immunotherapy, and radiotherapy. However, recent research has raised concerns about its side effects, including damage to immune cells, hematopoietic stem cells, liver, and kidneys, the development of cachexia, and the risk of secondary tumor formation. In this review, we provide an overview of these emerging findings, with a specific emphasis on elucidating the underlying mechanisms, and underscore the critical significance of effectively managing side effects associated with targeted ferroptosis-based therapy.

Iron plays a crucial role in many physiological processes, including oxygen transport, bioenergetics, and immune function. Iron is assimilated from food and also recycled from senescent red blood cells. Iron exists in two dietary forms: heme (animal based) and non-heme (mostly plant based). The body uses iron for metabolic purposes, and stores the excess mainly in splenic and hepatic macrophages. Physiologically, iron excretion in humans is inefficient and not highly regulated, so regulation of intestinal absorption maintains iron homeostasis. Iron losses occur at a steady rate via turnover of the intestinal epithelium, blood loss, and exfoliation of dead skin cells, but overall iron homeostasis is tightly controlled at cellular and systemic levels. Aging can have a profound impact on iron homeostasis and induce a dyshomeostasis where iron deficiency or overload (sometimes both simultaneously) can occur, potentially leading to several disorders and pathologies. To maintain physiologically balanced iron levels, reduce risk of disease, and promote healthy aging, it is advisable for older adults to follow recommended daily intake guidelines and periodically assess iron levels. Clinicians can evaluate body iron status using different techniques but selecting an assessment method primarily depends on the condition being examined. This review provides a comprehensive overview of the forms, sources, and metabolism of dietary iron, associated disorders of iron dyshomeostasis, assessment of iron levels in older adults, and nutritional guidelines and strategies to maintain iron balance in older adults.