Parkin and mitophagy in cancer. Oncogene. 2016; Epub ahead of print. [PMID: 27593930 DOI: 10.1038/onc.2016.302]

Mitochondrial Genome-Encoded lncND5 Regulates Mitophagy in Hypoxic Pulmonary Artery Smooth Muscle Cell

Long noncoding RNAs (lncRNAs) are implicated in pulmonary hypertension (PH) progression. However, the underlying mechanisms remain largely unknown. Although mitophagy plays a crucial role in hypoxia-induced PH pathogenesis, the role of lncRNAs in mitophagy remains unclear. Especially, the mechanism of lncRNA encoded by the mitochondrial genome in regulating mitophagy needs to be elucidated. We explored the role of lncND5 in human pulmonary artery smooth muscle cells (PASMCs) and Sugen5416 plus hypoxia (SuHx)-induced PH mouse model in vitro and in vivo. LncND5 expression and localization were detected using real-time quantitative polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization (FISH). We investigated the molecular mechanism of lncND5 using western blotting, flow cytometry, RNA immunoprecipitation, RNA pulldown, transmission electron microscopy (TEM), immunofluorescence (IF), and echocardiography. Mitochondrial lncND5 expression was decreased under hypoxia in human PASMCs. Mechanistically, in the mitochondria, lncND5 maintains complex I activity by binding with mitochondrial ADH-ubiquinone oxidoreductase chain 5 (MT-ND5) at nucleotides 1086-1159 bp, thereby regulating mitochondrial reactive oxygen species (mROS) release and alleviating mitophagy. Additionally, lncND5 regulates mitophagy via cardiolipin (CL), which regulates complex I activity, inhibiting ROS release then relieving mitophagy. In the cytoplasm, lncND5 inhibits mitophagy by directly interacting with hydroxymethylglutaryl-CoA synthase 1 (HMGCS1). Notably, lncND5 is transported from the mitochondria to the cytoplasm and is mediated by TAR DNA-binding protein 43 (TDP-43). Our findings, for the first time, reveal that lncND5 may be a potential therapeutic approach for PH.

Identification and characterization of mitochondrial autophagy-related genes in osteosarcoma and predicting clinical prognosis

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.

PI3K and PINK1 Immunoexpression as Predictors of Survival in Patients Undergoing Resection of Brain Metastases from Lung Adenocarcinoma

Phosphoinositide 3-kinase (PI3K) and PTEN-induced kinase 1 (PINK1) are key regulators of metabolism and mitochondrial quality control. This study assessed their immunoexpression in 22 patients with lung adenocarcinoma and resected brain metastases who underwent curative treatment between 2007 and 2017 and evaluated their prognostic significance. Tissue microarrays of primary tumors and matched metastases were analyzed using the H-score method. PI3K expression was significantly higher in primary tumors (96.8 ± 57.9 vs. 43.5 ± 62.3; p = 0.003) and in stage IV adenocarcinomas (113.3 ± 56.3 vs. 61.4 ± 47.1; p = 0.043). PINK1 expression showed no significant variation across disease stages. Univariate analysis identified older age (>55 years), PI3K overexpression (HR = 7.791, 95% CI 1.718-36.432; >50 points), and PINK1 overexpression (>100 points) in primary tumors as predictors of poor overall survival (HR = 2.236, 95% CI 1.109-4.508; p = 0.025). Multivariate analysis confirmed PINK1 overexpression in primary tumors as an independent prognostic factor (HR = 4.328, 95% CI 1.264-14.814; p = 0.020). These findings suggest that PI3K and PINK1 may serve as prognostic biomarkers in lung adenocarcinoma with resected brain metastases, emphasizing the need for research on their role in tumor progression and therapeutic response.

A Novel Prognostic Signature of Mitophagy-Related E3 Ubiquitin Ligases in Breast Cancer

Mitophagy plays a critical role in maintaining mitochondrial quality and cellular homeostasis. But the specific contribution of mitophagy-related E3 ubiquitin ligases to prognoses remains largely unexplored. In this study, we identified a novel mitophagy-related E3 ubiquitin ligase prognostic signature using least absolute shrinkage and selector operator (LASSO) and multivariate Cox regression analyses in breast cancer. Based on median risk scores, patients were divided into high-risk and low-risk groups. Functional enrichment analyses were conducted to explore the biological differences between the two groups. Immune infiltration, drug sensitivity, and mitochondrial-related phenotypes were also analyzed to evaluate the clinical implications of the model. A four-gene signature (ARIH1, SIAH2, UBR5, and WWP2) was identified, and Kaplan-Meier analysis demonstrated that the high-risk group had significantly worse overall survival (OS). The high-risk patients exhibited disrupted mitochondrial metabolism and immune dysregulation with upregulated immune checkpoint molecules. Additionally, the high-risk group exhibited higher sensitivity to several drugs targeting the Akt/PI3K/mTORC1 signaling axis. Accompanying mitochondrial metabolic dysregulation, mtDNA stress was elevated, contributing to activation of the senescence-associated secretory phenotype (SASP) in the high-risk group. In conclusion, the identified signature provides a robust tool for risk stratification and offers insights into the interplay between mitophagy, immune modulation, and therapeutic responses for breast cancer.

Computational Study of the Activation Mechanism of Wild-Type Parkin and Its Clinically Relevant Mutant

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder. It impairs the control of movement and balance. Parkin mutations worsen the symptoms in sporadic cases and cause the early onset of the disease. Therefore, recent efforts have focused on the rescue of defective parkin by engineered proteins or small-molecule activators to enhance parkin activation. These attempts require holistic understanding of the multistep activation mechanism and molecular effects of disease-associated mutations. Hereby, we provided a comprehensive analysis of the activation mechanism of parkin and a clinically relevant mutant, parkinS167N, using molecular dynamics simulations based on the following crystal structures: (1) parkin, (2) parkin/pUb (phosphorylated Ubiquitin), (3) pparkin/pUb, and (4) pparkin/pUb/UbcH7-Ub. Each of these represents an individual step in the activation process. We showed that the mutation impacted the dynamics of not only the RING0 domain, where it is localized, but also the RING2, Ubl, and IBR domains. We identified residues participating in the allosteric interaction network involved in parkin activation. Some of them are mutated in PD-associated parkin variants. The RING0 domain provides a binding interface with various proteins, so understanding problems associated with the mutation paves the way to the discovery of effective engineered proteins or small molecules that activate mutant parkin.

Susceptibility of Mitophagy-Deficient Tumors to Ferroptosis Induction by Relieving the Suppression of Lipid Peroxidation

The identification of ferroptosis-sensitive cancers is critical for the application of ferroptosis-inducing therapies in cancer therapy. Here, patient-derived organoid screening models of colorectal cancer are established to identify tumors that are sensitive to ferroptosis-inducing therapy. This study discovers that patient-derived tumors characterized by mitophagy deficiency are hypersensitive to ferroptosis-inducing therapies. Mechanistically, a novel negative feedback regulatory pathway of lipid peroxidation is identified, which is one of the important intrinsic anti-ferroptosis mechanisms of cancer cells. Lipid peroxidation-mediated endoplasmic reticulum stress transcriptionally upregulates Parkin to promote mitophagy through ATF4. Mitophagy limits the generation of lipid peroxidation products and subsequently inhibits ferroptosis by inhibiting the accumulation of mitochondrial ROS. Mitophagy-deficient tumors lack this anti-ferroptotic mechanism, unleashing the generation of lipid peroxidation and potent ferroptotic cell death induced by erastin, RSL3, cysteine deprivation, radiotherapy, and immunotherapy. More importantly, ferroptosis-inducing therapy selectively inhibits the growth and distant metastasis of mitophagy-deficient tumors in vivo. In summary, patient-derived organoids of colorectal cancer patients for screening ferroptosis-sensitive tumors are established, providing a paradigm for identifying that patient-derived tumors are sensitive to ferroptosis-inducing therapies. This study concludes that mitophagy-deficient tumors are vulnerable to ferroptosis induction, which may lead to the development of new therapeutic strategies for tumors deficient in mitophagy.

Parkin modulates the hepatocellular carcinoma microenvironment by regulating PD-1/PD-L1 signalling

INTRODUCTION

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.

OBJECTIVE

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

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Parkin is a critical factor in grouper immune response to virus infection

Parkin is an E3 ubiquitinated ligase that mainly participates in mitophagy and plays an essential biological role in organisms. To investigate Parkin's function in fish, a Parkin homolog was cloned from Epinephelus coioides (EcParkin). The open reading frame (ORF) of EcParkin consists of 1461 nucleotides and encodes a protein of 486 amino acids, with a predicted molecular weight of 53.32 kDa. EcParkin was highly expressed in the heart, kidney, and head kidney of healthy groupers, especially in the heart. The expression levels of EcParkin were upregulated after Singapore grouper iridovirus (SGIV) and red-spotted grouper nervous necrosis virus (RGNNV) infection. Intracellular localization studies revealed that EcParkin is distributed in both the cytoplasm and nucleus of GS cells. Overexpression of EcParkin promoted SGIV and RGNNV replication in vitro, while knockdown of EcParkin inhibited SGIV and RGNNV replication. EcParkin suppressed the promoter activities of IFN-β, ISRE, and NF-κB, as well as the expression of interferon-related factors and inflammatory cytokines. EcParkin was found to colocalize and interact with EcMDA5, EcMAVS, EcTBK1, EcIRF3, and EcIRF7. Additionally, EcParkin enhanced LC3-II production in GS cells. These findings suggest that EcParkin may play a crucial role in the antiviral innate immunity and cellular autophagy of fish.

MANF facilitates breast cancer cell survival under glucose-starvation conditions via PRKN-mediated mitophagy regulation

During tumor expansion, breast cancer (BC) cells often experience reactive oxygen species accumulation and mitochondrial damage because of glucose shortage. However, the mechanism by which BC cells deal with the glucose-shortage-induced oxidative stress remains unclear. Here, we showed that MANF (mesencephalic astrocyte derived neurotrophic factor)-mediated mitophagy facilitates BC cell survival under glucose-starvation conditions. MANF-mediated mitophagy also promotes fatty acid oxidation in glucose-starved BC cells. Moreover, during glucose starvation, SENP1-mediated de-SUMOylation of MANF increases cytoplasmic MANF expression through the inhibition of MANF's nuclear translocation and hence renders mitochondrial distribution of MANF. MANF mediates mitophagy by binding to PRKN (parkin RBR E3 ubiquitin protein ligase), a key mitophagy regulator, in the mitochondria. Under conditions of glucose starvation, protein oxidation inhibits PRKN activity; nevertheless, the CXXC motif of MANF alleviates protein oxidation in RING II-domain of PRKN and restores its E3 ligase activity. Furthermore, MANF-PRKN interactions are essential for BC tumor growth and metastasis. High MANF expression predicts poor outcomes in patients with BC. Our results highlight the prosurvival role of MANF-mediated mitophagy in BC cells during glucose starvation, suggesting MANF as a potential therapeutic target.Abbreviation: 2DG, 2-deoxy-D-glucose; 5TG, 5-thio-D-glucose; ACSL4/FACL4, acyl-CoA synthetase long chain family member 4; Baf A1, bafilomycin A1; BRCA, breast cancer; CHX, cycloheximide; DMF, distant metastasis-free; DMFS, distant metastasis-free survival; ECM, extracellular matrix; ER, endoplasmic reticulum; ERS, endoplasmic reticulum stress; F-1,6-BP, fructose-1,6-bisphosphate; FAO, fatty acid oxidation; GSH, reduced glutathione; GSVA, gene set variation analysis; HCC, hepatocellular carcinoma; ICC, intrahepatic cholangiocarcinoma; IF, immunofluorescence; MANF, mesencephalic astrocyte derived neurotrophic factor; Mdivi-1, mitochondrial division inhibitor 1; MFI, mean fluorescence intensity; NAC, N-acetyl-L-cysteine; OCR, oxygen-consumption rate; OS, overall survival; PMI, SQSTM1/p62-mediated mitophagy inducer; PPP, pentose phosphate pathway; PRKN, parkin RBR E3 ubiquitin protein ligase; RBR, RING in between RING; RFS, relapse-free survival; ROS, reactive oxygen species; SAPLIPs, saposin-like proteins; TCGA, The Cancer Genome Atlas; TNBC, triple-negative breast cancer; WT, wild type.

Hypoxia-induced BNIP3 facilitates the progression and metastasis of uveal melanoma by driving metabolic reprogramming

Uveal melanoma (UM) is an aggressive intraocular malignancy derived from melanocytes in the uvea tract of the eye. Up to 50% of patients with UM develop distant metastases which is usually fatal within one year; preventing metastases is therefore essential. Metabolic reprogramming plays a critical role in UM progression and metastasis. However, the metabolic phenotype of UM cells in the hypoxic tumor is not well understood. Here, we report that hypoxia-induced BNIP3 reprograms tumor cell metabolism, promoting their survival and metastasis. In response to hypoxia, BNIP3-mediated mitophagy alleviates mitochondrial dysfunction and enhances mitochondrial oxidative phosphorylation (OXPHOS) while simultaneously reducing mitochondrial reactive oxygen species (mtROS) production. This, in turn, impairs HIF1A/HIF-1α protein stability and inhibits glycolysis. Inhibition of mitophagy significantly suppresses BNIP3-induced UM progression and metastasis in vitro and in vivo. Collectively, these observations demonstrate a novel mechanism whereby BNIP3 promotes UM metabolic reprogramming and malignant progression by mediating hypoxia-induced mitophagy and suggest that BNIP3 could be an important therapeutic target to prevent metastasis in patients with UM.Abbreviations: AOD: average optical density; BNIP3: BCL2/adenovirus E1B interacting protein 3; CQ: chloroquine; CoCl2: cobalt chloride; GEPIA: Gene Expression Profiling Interactive Analysis; HIF1A: hypoxia inducible factor 1, alpha subunit; IHC: immunohistochemistry; mtROS: mitochondrial reactive oxygen species; NAC: N-acetylcysteine; OCR: oxygen consumption rate; OXPHOS: oxidative phosphorylation; ROS: reactive oxygen species; TCGA: The Cancer Genome Atlas; UM: uveal melanoma.

piR-823 tale as emerging cancer-hallmark molecular marker in different cancer types: a step-toward ncRNA-precision

PIWI-interacting RNAs (piRNAs) have received a lot of attention for their functions in cancer research. This class of short non-coding RNAs (ncRNA) has roles in genomic stability, chromatin remodeling, messenger RNA (mRNA) integrity, and genome structure. We summarized the mechanisms underlying the biogenesis and regulatory molecular functions of piRNAs. Among all piRNAs studied in cancer, this review offers a comprehensive analysis of the emerging roles of piR-823 in various types of cancer, including colorectal, gastric, liver, breast, and renal cancers, as well as multiple myeloma. piR-823 has emerged as a crucial modulator of various cancer hallmarks through regulating multiple pathways. In the current review, we analyzed several databases and conducted an extensive literature search to explore the influence of piR-823 in carcinogenesis in addition to describing the potential application of piR-823 as prognostic and diagnostic markers as well as the therapeutic potential toward ncRNA precision.

Detoxification of Chlorfenapyr by a Parkin-GSTd2 Module in Bactrocera dorsalis (Diptera: Tephritidae)

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a highly invasive and destructive pest. Chlorfenapyr is a widely used insecticide that disrupts mitochondrial activity. The Parkin protein plays conserved roles in maintaining mitochondrial homeostasis, but the role of Parkin in response to chlorfenapyr remains largely unknown. Here, we report that BdParkin is required for chlorfenapyr detoxification, and dsRNA targeting BdParkin improves the insecticidal efficacy of chlorfenapyr. Among the genes whose expression levels are affected by BdParkin RNAi, knock-down of the glutathione S-transferase gene BdGSTd2 increases the insecticidal efficacy of chlorfenapyr. Molecular docking reveals potential interactions between BdGSTd2 and tralopyril, an insecticidal metabolite of chlorfenapyr. These results suggest that BdParkin could impact the response of B. dorsalis to chlorfenapyr through metabolic processes regulated by BdGSTd2. Our findings could offer new insights into how insects detoxify chlorfenapyr and provide molecular targets for developing a sustainable management strategy for B. dorsalis.

Ciclopirox platinum(IV) conjugates suppress tumors by promoting mitophagy and provoking immune responses

Mitophagy is an important target for antitumor drugs development. A series of ciclopirox (CPX) platinum(IV) hybrids targeting PTEN induced putative kinase 1 (PINK1)/Parkin mediated mitophagy were designed and prepared as antitumor agents. The dual CPX platinum(IV) complex with cisplatin core was screened out as a candidate, which displayed promising antitumor activities both in vitro and in vivo. Mechanistically, it caused serious DNA damage in tumor cells. Then, remarkable mitochondrial damage was induced accompanied by the mitochondrial membrane depolarization and reactive oxygen species generation, which further promoted apoptosis through the Bcl-2/Bax/Caspase3 pathway. Furthermore, mitophagy was ignited via the PINK1/Parkin/P62/LC3 axis, and exhibited positive influence on promoting the apoptosis of tumor cells. The antitumor immunity was boosted by the block of immune check point programmed cell death ligand-1 (PD-L1), which further increased the density of T cells in tumors. Subsequently, the metastasis of tumor cells was inhibited by inhibiting angiogenesis in tumors.

Gentiana decoction inhibits liver fibrosis and the activation of hepatic stellate cells via upregulating the expression of Parkin

Liver fibrosis is a wound-healing process. It can be induced by various chronic liver diseases. Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs), a key event. However, no effective treatment strategies to cure or alleviate liver fibrosis-induced pathologic changes have yet been developed. Traditional Chinese medicine (TCM) exhibits a good anti-fibrosis action, with few side effects. Gentiana decoction, a TCM also called Longdan Xiegan Tang (LXT), is used for purging the liver in clinical settings. However, the role of LXT in preventing liver fibrosis and the underlying regulatory mechanism have not yet been investigated. This study demonstrates that LXT treatment can protect the liver from the injuries resulting from CCl4-induced liver fibrosis in mice and suppress the activation of HSCs. The mice in the LXT group exhibit litter collagen I and HSC activation marker α-smooth muscle actin (α-SMA) expression. Transcriptome sequencing of the mouse liver tissue reveals that the level of Parkin, a mitophagy marker, decreased in CCl4-induced liver fibrosis. Further study shows that the injection of Parkin-overexpression adeno-associated virus (Parkin-AAV) via the tail vein can reduce CCl4-induced liver fibrogenesis in mice. We conducted a mechanistic study also, which suggests that LXT treatment suppresses the activation of HSCs by upregulating the expression of Parkin. Hence, it can be suggested that LXT inhibits liver fibrosis by activating the Parkin signaling pathway.

Phytochemicals regulate cancer metabolism through modulation of the AMPK/PGC-1α signaling pathway

BACKGROUND

Due to the complex pathophysiological mechanisms involved in cancer progression and metastasis, current therapeutic approaches lack efficacy and have significant adverse effects. Therefore, it is essential to establish novel strategies for combating cancer. Phytochemicals, which possess multiple biological activities, such as antioxidant, anti-inflammatory, antimutagenic, immunomodulatory, antiproliferative, anti-angiogenesis, and antimetastatic properties, can regulate cancer progression and interfere in various stages of cancer development by suppressing various signaling pathways.

METHODS

The current systematic and comprehensive review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria, using electronic databases, including PubMed, Scopus, and Science Direct, until the end of December 2023. After excluding unrelated articles, 111 related articles were included in this systematic review.

RESULTS

In this current review, the major signaling pathways of cancer metabolism are highlighted with the promising anticancer role of phytochemicals. This was through their ability to regulate the AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) signaling pathway. The AMPK/PGC-1α signaling pathway plays a crucial role in cancer cell metabolism via targeting energy homeostasis and mitochondria biogenesis, glucose oxidation, and fatty acid oxidation, thereby generating ATP for cell growth. As a result, targeting this signaling pathway may represent a novel approach to cancer treatment. Accordingly, alkaloids, phenolic compounds, terpene/terpenoids, and miscellaneous phytochemicals have been introduced as promising anticancer agents by regulating the AMPK/PGC-1α signaling pathway. Novel delivery systems of phytochemicals targeting the AMPK/PGC-1α pathway in combating cancer are also highlighted in this review.

Cell life-or-death events in osteoporosis: All roads lead to mitochondrial dynamics

Mitochondria exhibit heterogeneous shapes and networks within and among cell types and tissues, also in normal or osteoporotic bone tissues with complex cell types. This dynamic characteristic is determined by the high plasticity provided by mitochondrial dynamics and is stemmed from responding to the survival and functional requirements of various bone cells in a specific microenvironments. In contrast, mitochondrial dysfunction, induced by dysregulation of mitochondrial dynamics, may act as a trigger of cell death signals, including common apoptosis and other forms of programmed cell death (PCD). These PCD processes consisting of tightly structured cascade gene expression events, can further influence the bone remodeling by facilitating the death of various bone cells. Mitochondrial dynamics, therefore, drive the bone cells to stand at the crossroads of life and death by integrating external signals and altering metabolism, shape, and signal-response properties of mitochondria. This implies that targeting mitochondrial dynamics displays significant potential in treatment of osteoporosis. Considerable effort has been made in osteoporosis to emphasize the parallel roles of mitochondria in regulating energy metabolism, calcium signal transduction, oxidative stress, inflammation, and cell death. However, the emerging field of mitochondrial dynamics-related PCD is not well understood. Herein, to bridge the gap, we outline the latest knowledge on mitochondrial dynamics regulating bone cell life or death during normal bone remodeling and osteoporosis.

Role of Autophagy and AMPK in Cancer Stem Cells: Therapeutic Opportunities and Obstacles in Cancer

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.

Amentoflavone regulates the miR-124-3p/CAPN2 axis to promote mitochondrial autophagy in HCC cells

BACKGROUND

Hepatocellular carcinoma (HCC) is a disease with poor prognosis and high mortality. Amentoflavone (AF) possesses the characteristics of marginal toxicity, stable curative effect, and good anti-HCC activity. This study aimed to evaluate the molecular mechanism of AF inhibiting HCC and provide a new idea for HCC treatment.

METHODS

Clinical tissue of HCC was collected. AF was given with HCC cells, and transfected with corresponding vectors. MiR-124-3p expression in HCC clinical samples and cells was ascertained by qRT-PCR assay. HCC cells viability was identified by CCK-8 assay. LC3 protein expression was ascertained by immunofluorescence assay. The expressions of CAPN2, β-catenin and mitochondrial autophagy-related proteins were detected by western blot. Dual-luciferase reporter gene assay confirmed the targeting relationship of miR-124-3p and CAPN2.

RESULTS

MiR-124-3p expression was inhibited and CAPN2 expression was increased in HCC tissues and cells. AF decreased HCC cell viability, up-regulated miR-124-3p expression, and inhibited CAPN2 expression and β-catenin nuclear transcription. Moreover, AF could activate the mitochondrial autophagy of HCC cells. MiR-124-3p specifically regulated CAPN2 expression. This study found that CAPN2 could promote β-catenin nuclear translocation, thus activating wnt/β-catenin pathway to inhibit mitochondrial autophagy in HCC cells. MiR-124-3p mimics enhanced AF function in promoting mitochondrial autophagy in HCC cells. However, CAPN2 overexpression, miR-124-3p inhibitor and SKL2001 attenuated the effectiveness of AF.

CONCLUSION

This study confirmed that AF regulated miR-124-3p/CAPN2 axis to restraint β-catenin nuclear translocation and then inhibit the wnt/β-catenin pathway, thereby promoting mitochondrial autophagy in HCC.

The bioenergetic landscape of cancer

BACKGROUND

Bioenergetic remodeling of core energy metabolism is essential to the initiation, survival, and progression of cancer cells through exergonic supply of adenosine triphosphate (ATP) and metabolic intermediates, as well as control of redox homeostasis. Mitochondria are evolutionarily conserved organelles that mediate cell survival by conferring energetic plasticity and adaptive potential. Mitochondrial ATP synthesis is coupled to the oxidation of a variety of substrates generated through diverse metabolic pathways. As such, inhibition of the mitochondrial bioenergetic system by restricting metabolite availability, direct inhibition of the respiratory Complexes, altering organelle structure, or coupling efficiency may restrict carcinogenic potential and cancer progression.

SCOPE OF REVIEW

Here, we review the role of bioenergetics as the principal conductor of energetic functions and carcinogenesis while highlighting the therapeutic potential of targeting mitochondrial functions.

MAJOR CONCLUSIONS

Mitochondrial bioenergetics significantly contribute to cancer initiation and survival. As a result, therapies designed to limit oxidative efficiency may reduce tumor burden and enhance the efficacy of currently available antineoplastic agents.

Regulation and Functions of Autophagy During Animal Development

Autophagy is used to degrade cytoplasmic materials, and is critical to maintain cell and organismal health in diverse animals. Here we discuss the regulation, utilization and impact of autophagy on development, including roles in oogenesis, spermatogenesis and embryogenesis in animals. We also describe how autophagy influences postembryonic development in the context of neuronal and cardiac development, wound healing, and tissue regeneration. We describe recent studies of selective autophagy during development, including mitochondria-selective autophagy and endoplasmic reticulum (ER)-selective autophagy. Studies of developing model systems have also been used to discover novel regulators of autophagy, and we explain how studies of autophagy in these physiologically relevant systems are advancing our understanding of this important catabolic process.

Complex Interplay between DNA Damage and Autophagy in Disease and Therapy

Cancer, a multifactorial disease characterized by uncontrolled cellular proliferation, remains a global health challenge with significant morbidity and mortality. Genomic and molecular aberrations, coupled with environmental factors, contribute to its heterogeneity and complexity. Chemotherapeutic agents like doxorubicin (Dox) have shown efficacy against various cancers but are hindered by dose-dependent cytotoxicity, particularly on vital organs like the heart and brain. Autophagy, a cellular process involved in self-degradation and recycling, emerges as a promising therapeutic target in cancer therapy and neurodegenerative diseases. Dysregulation of autophagy contributes to cancer progression and drug resistance, while its modulation holds the potential to enhance treatment outcomes and mitigate adverse effects. Additionally, emerging evidence suggests a potential link between autophagy, DNA damage, and caretaker breast cancer genes BRCA1/2, highlighting the interplay between DNA repair mechanisms and cellular homeostasis. This review explores the intricate relationship between cancer, Dox-induced cytotoxicity, autophagy modulation, and the potential implications of autophagy in DNA damage repair pathways, particularly in the context of BRCA1/2 mutations.

Mitochondrial dysfunction and its association with age-related disorders

Aging is a complex process that features a functional decline in many organelles. Various factors influence the aging process, such as chromosomal abnormalities, epigenetic changes, telomere shortening, oxidative stress, and mitochondrial dysfunction. Mitochondrial dysfunction significantly impacts aging because mitochondria regulate cellular energy, oxidative balance, and calcium levels. Mitochondrial integrity is maintained by mitophagy, which helps maintain cellular homeostasis, prevents ROS production, and protects against mtDNA damage. However, increased calcium uptake and oxidative stress can disrupt mitochondrial membrane potential and permeability, leading to the apoptotic cascade. This disruption causes increased production of free radicals, leading to oxidative modification and accumulation of mitochondrial DNA mutations, which contribute to cellular dysfunction and aging. Mitochondrial dysfunction, resulting from structural and functional changes, is linked to age-related degenerative diseases. This review focuses on mitochondrial dysfunction, its implications in aging and age-related disorders, and potential anti-aging strategies through targeting mitochondrial dysfunction.

Salidroside Inhibits α-Amanitin-Induced AML-12 Cell Apoptosis via the Regulation of PINK1/Parkin-Mediated Mitophagy and Mitochondrial Function

Poisoning caused by the mushroom Amanita phalloides, due to the toxin α-amanitin, accounts for approximately 90% of food poisoning deaths in China with no specific antidotes. To investigate the role of salidroside (Sal) in α-amanitin (α-AMA)-induced mitophagy, mouse liver cells AML-12 were exposed to α-AMA in the presence of Sal or not. Intracellular reactive oxygen species (ROS) levels were measured using a ROS detection kit, mitochondrial activity was evaluated using a mitochondrial red fluorescent probe kit or JC-1 dye, and protein expression levels of PINK1, Parkin, LC3 II, P62, Bax, Bcl-2, Caspase 3, Cleaved-Caspase 3, PARP I, and Cleaved-PARP I were detected through Western blot. Results demonstrated that α-AMA led to increased intracellular ROS levels, cell apoptosis, and decreased mitochondrial membrane potential. Notably, expression levels of mitophagy-related proteins PINK1, Parkin, and LC3 increased significantly while the P62 protein expression decreased remarkably. Furthermore, Sal reversed the α-AMA-induced decrease in cell viability and mitochondrial membrane potential and increase in intracellular ROS level. In addition, Sal promoted expression levels of PINK1, Parkin, and LC3 II while suppressing the Bax/Bcl-2 ratio, Cleaved-Caspase 3, and Cleaved-PARP I as well as P62. The results above proved that salidroside alleviates α-AMA-induced mouse liver cells damage via promoting PINK1/Parkin-mediated mitophagy and reducing cell apoptosis.

SuperAgers and centenarians, dynamics of healthy ageing with cognitive resilience

Graceful healthy ageing and extended longevity is the most desired goal for human race. The process of ageing is inevitable and has a profound impact on the gradual deterioration of our physiology and health since it triggers the onset of many chronic conditions like dementia, osteoporosis, diabetes, arthritis, cancer, and cardiovascular disease. However, some people who lived/live more than 100 years called 'Centenarians" and how do they achieve their extended lifespans are not completely understood. Studying these unknown factors of longevity is important not only to establish a longer human lifespan but also to manage and treat people with shortened lifespans suffering from age-related morbidities. Furthermore, older adults who maintain strong cognitive function are referred to as "SuperAgers" and may be resistant to risk factors linked to cognitive decline. Investigating the mechanisms underlying their cognitive resilience may contribute to the development of therapeutic strategies that support the preservation of cognitive function as people age. The key to a long, physically, and cognitively healthy life has been a mystery to scientists for ages. Developments in the medical sciences helps us to a better understanding of human physiological function and greater access to medical care has led us to an increase in life expectancy. Moreover, inheriting favorable genetic traits and adopting a healthy lifestyle play pivotal roles in promoting longer and healthier lives. Engaging in regular physical activity, maintaining a balanced diet, and avoiding harmful habits such as smoking contribute to overall well-being. The synergy between positive lifestyle choices, access to education, socio-economic factors, environmental determinants and genetic supremacy enhances the potential for a longer and healthier life. Our article aims to examine the factors associated with healthy ageing, particularly focusing on cognitive health in centenarians. We will also be discussing different aspects of ageing including genomic instability, metabolic burden, oxidative stress and inflammation, mitochondrial dysfunction, cellular senescence, immunosenescence, and sarcopenia.

PRKN-linked familial Parkinson's disease: cellular and molecular mechanisms of disease-linked variants

Parkinson's disease (PD) is a common and incurable neurodegenerative disorder that arises from the loss of dopaminergic neurons in the substantia nigra and is mainly characterized by progressive loss of motor function. Monogenic familial PD is associated with highly penetrant variants in specific genes, notably the PRKN gene, where homozygous or compound heterozygous loss-of-function variants predominate. PRKN encodes Parkin, an E3 ubiquitin-protein ligase important for protein ubiquitination and mitophagy of damaged mitochondria. Accordingly, Parkin plays a central role in mitochondrial quality control but is itself also subject to a strict protein quality control system that rapidly eliminates certain disease-linked Parkin variants. Here, we summarize the cellular and molecular functions of Parkin, highlighting the various mechanisms by which PRKN gene variants result in loss-of-function. We emphasize the importance of high-throughput assays and computational tools for the clinical classification of PRKN gene variants and how detailed insights into the pathogenic mechanisms of PRKN gene variants may impact the development of personalized therapeutics.

RN0D, a galactoglucan from Panax notoginseng flower induces cancer cell death via PINK1/Parkin mitophagy

Metabolic alterations within mitochondria, encompassing processes such as autophagy and energy metabolism, play a pivotal role in facilitating the swift proliferation, invasion, and metastasis of cancer cells. Despite this, there is a scarcity of currently available medications with proven anticancer efficacy through the modulation of mitochondrial dysfunction in a clinical setting. Here, we introduce the structural characteristics of RN0D, a galactoglucan isolated and purified from Panax notoginseng flowers, mainly composed of β-1,4-galactan and β-1,3/1,6-glucan. RN0D demonstrates the capacity to induce mitochondrial impairment in cancer cells, leading to the accumulation of reactive oxygen species, initiation of mitophagy, and reduction in both mitochondrial number and size. This sequence of events ultimately results in the inhibition of mitochondrial and glycolytic bioenergetics, culminating in the demise of cancer cells due to adenosine triphosphate (ATP) deprivation. Notably, the observed bioactivity is attributed to RN0D's direct targeting of Galectin-3, as affirmed by surface plasmon resonance studies. Furthermore, RN0D is identified as an activator of the PTEN-induced kinase 1 (PINK1)/Parkin pathway, ultimately instigating cytotoxic mitophagy in tumor cells. This comprehensive study substantiates the rationale for advancing RN0D as a potentially efficacious anticancer therapeutic.

LYC inhibits the AKT signaling pathway to activate autophagy and ameliorate TGFB-induced renal fibrosis

Renal fibrosis is a typical pathological change in chronic kidney disease (CKD). Epithelial-mesenchymal transition (EMT) is the predominant stage. Activation of macroautophagy/autophagy plays a crucial role in the process of EMT. Lycopene (LYC) is a highly antioxidant carotenoid with pharmacological effects such as anti-inflammation, anti-apoptosis and mediation of autophagy. In this study, we demonstrated the specific mechanism of LYC in activating mitophagy and improving renal fibrosis. The enrichment analysis results of GO and KEGG showed that LYC had high enrichment values with autophagy. In this study, we showed that LYC alleviated aristolochic acid I (AAI)-induced intracellular expression of PINK1, TGFB/TGF-β, p-SMAD2, p-SMAD3, and PRKN/Parkin, recruited expression of MAP1LC3/LC3-II and SQSTM1/p62, decreased mitochondrial membrane potential (MMP), and ameliorated renal fibrosis in mice. When we simultaneously intervened NRK52E cells using bafilomycin A1 (Baf-A1), AAI, and LYC, intracellular MAP1LC3-II and SQSTM1 expression was significantly increased. A similar result was seen in renal tissue and cells when treated in vitro and in vivo with CQ, AAI, and LYC, and the inhibitory effect of LYC on the AAI-activated SMAD2-SMAD3 signaling pathway was attenuated. Molecular docking simulation experiments showed that LYC stably bound to the AKT active site. After intervention of cells with AAI and GSK-690693, the expression of PINK1, PRKN, MAP1LC3-II, BECN1, p-SMAD2 and p-SMAD3 was increased, and the expression of SQSTM1 was decreased. However, SC79 inhibited autophagy and reversed the inhibitory effect of LYC on EMT. The results showed that LYC could inhibit the AKT signaling pathway to activate mitophagy and reduce renal fibrosis.Abbreviation: AA: aristolochic acid; ACTA2/α-SMA: actin alpha 2, smooth muscle, aorta; ACTB: actin beta; AKT/protein kinase B: thymoma viral proto-oncogene; BAF-A1: bafilomycin A1; BECN1: beclin 1, autophagy related; CCN2/CTGF: cellular communication network factor 2; CDH1/E-Cadherin: cadherin 1; CKD: chronic kidney disease; COL1: collagen, type I; COL3: collagen, type III; CQ: chloroquine; ECM: extracellular matrix; EMT: epithelial-mesenchymal transition; FN1: fibronectin 1; LYC: lycopene; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MMP: mitochondrial membrane potential; MTOR: mechanistic target of rapamycin kinase ; PI3K: phosphoinositide 3-kinase; PINK1: PTEN induced putative kinase 1; PRKN/Parkin: parkin RBR E3 ubiquitin protein ligase; PPI: protein-protein interaction; SMAD2: SMAD family member 2; SMAD3: SMAD family member 3; SQSTM1/p62: sequestosome 1; TGFB/TGFβ: transforming growth factor, beta; VIM: vimentin.

Chronic replication stress invokes mitochondria dysfunction via impaired parkin activity

Replication stress is a major contributor to tumorigenesis because it provides a source of chromosomal rearrangements via recombination events. PARK2, which encodes parkin, a regulator of mitochondrial homeostasis, is located on one of the common fragile sites that are prone to rearrangement by replication stress, indicating that replication stress may potentially impact mitochondrial homeostasis. Here, we show that chronic low-dose replication stress causes a fixed reduction in parkin expression, which is associated with mitochondrial dysfunction, indicated by an increase in mtROS. Consistent with the major role of parkin in mitophagy, reduction in parkin protein expression was associated with a slight decrease in mitophagy and changes in mitochondrial morphology. In contrast, cells expressing ectopic PARK2 gene does not show mtROS increases and changes in mitochondrial morphology even after exposure to chronic replication stress, suggesting that intrinsic fragility at PARK2 loci associated with parkin reduction is responsible for mitochondrial dysfunction caused by chronic replication stress. As endogenous replication stress and mitochondrial dysfunction are both involved in multiple pathophysiology, our data support the therapeutic development of recovery of parkin expression in human healthcare.

A mutational atlas for Parkin proteostasis

Proteostasis can be disturbed by mutations affecting folding and stability of the encoded protein. An example is the ubiquitin ligase Parkin, where gene variants result in autosomal recessive Parkinsonism. To uncover the pathological mechanism and provide comprehensive genotype-phenotype information, variant abundance by massively parallel sequencing (VAMP-seq) is leveraged to quantify the abundance of Parkin variants in cultured human cells. The resulting mutational map, covering 9219 out of the 9300 possible single-site amino acid substitutions and nonsense Parkin variants, shows that most low abundance variants are proteasome targets and are located within the structured domains of the protein. Half of the known disease-linked variants are found at low abundance. Systematic mapping of degradation signals (degrons) reveals an exposed degron region proximal to the so-called "activation element". This work provides examples of how missense variants may cause degradation either via destabilization of the native protein, or by introducing local signals for degradation.

Constructing and Evaluating a Mitophagy-Related Gene Prognostic Model: Implications for Immune Landscape and Tumor Biology in Lung Adenocarcinoma

Mitophagy, a conserved cellular mechanism, is crucial for cellular homeostasis through the selective clearance of impaired mitochondria. Its emerging role in cancer development has sparked interest, particularly in lung adenocarcinoma (LUAD). Our study aimed to construct a risk model based on mitophagy-related genes (MRGs) to predict survival outcomes, immune response, and chemotherapy sensitivity in LUAD patients. We mined the GeneCards database to identify MRGs and applied LASSO/Cox regression to formulate a prognostic model. Validation was performed using two independent Gene Expression Omnibus (GEO) cohorts. Patients were divided into high- and low-risk categories according to the median risk score. The high-risk group demonstrated significantly reduced survival. Multivariate Cox analysis confirmed the risk score as an independent predictor of prognosis, and a corresponding nomogram was developed to facilitate clinical assessments. Intriguingly, the risk score correlated with immune infiltration levels, oncogenic expression profiles, and sensitivity to anticancer agents. Enrichment analyses linked the risk score with key oncological pathways and biological processes. Within the model, MTERF3 emerged as a critical regulator of lung cancer progression. Functional studies indicated that the MTERF3 knockdown suppressed the lung cancer cell proliferation and migration, enhanced mitophagy, and increased the mitochondrial superoxide production. Our novel prognostic model, grounded in MRGs, promises to refine therapeutic strategies and prognostication in lung cancer management.

DMT1-dependent endosome-mitochondria interactions regulate mitochondrial iron translocation and metastatic outgrowth

Transient early endosome (EE)-mitochondria interactions can mediate mitochondrial iron translocation, but the associated mechanisms are still elusive. We showed that Divalent Metal Transporter 1 (DMT1) sustains mitochondrial iron translocation via EE-mitochondria interactions in triple-negative MDA-MB-231, but not in luminal A T47D breast cancer cells. DMT1 silencing increases labile iron pool (LIP) levels and activates PINK1/Parkin-dependent mitophagy in MDA-MB-231 cells. Mitochondrial bioenergetics and the iron-associated protein profile were altered by DMT1 silencing and rescued by DMT1 re-expression. Transcriptomic profiles upon DMT1 silencing are strikingly different between 2D and 3D culture conditions, suggesting that the environment context is crucial for the DMT1 knockout phenotype observed in MDA-MB-231 cells. Lastly, in vivo lung metastasis assay revealed that DMT1 silencing promoted the outgrowth of lung metastatic nodules in both human and murine models of triple-negative breast cancer cells. These findings reveal a DMT1-dependent pathway connecting EE-mitochondria interactions to mitochondrial iron translocation and metastatic fitness of breast cancer cells.

Homocysteine and mitochondrial quality control in diabetic retinopathy

BACKGROUND

Diabetic retinopathy is a progressive disease, and one of the key metabolic abnormalities in the pathogenesis of diabetic retinopathy, mitochondrial damage, is also influenced by the duration of hyperglycemia. Mitochondrial quality control involves a coordination of mitochondrial dynamics, biogenesis and removal of the damaged mitochondria. In diabetes, these processes are impaired, and the damaged mitochondria continue to produce free radicals. Diabetic patients also have high homocysteine and reduced levels of hydrogen sulfide, and hyperhomocysteinemia is shown to exacerbate diabetes-induced mitochondrial damage and worsen their dynamics. This study aims to investigate the temporal relationship between hyperhomocysteinemia and retinal mitochondrial quality control in diabetic retinopathy.

METHODS

Human retinal endothelial cells incubated in 20 mM D-glucose for 24 to 96 h, in the absence or presence of 100 µM homocysteine, with/without a hydrogen sulfide donor GYY4137, were analyzed for mitochondrial ROS (MitoSox fluorescence), DNA damage (transcripts of mtDNA-encoded ND6 and CytB), copy numbers, oxygen consumption rate (Seahorse XF analyzer) and mitophagy (mitophagosomes immunofluorescence labeling and flow cytometry). Results were confirmed in the retina from mice genetically manipulated for hyperhomocysteinemia (cystathionine β-synthase deficient mice, Cbs+/-), streptozotocin-induced diabetic for 8 to 24 weeks. At 24 weeks of diabetes, vascular health was evaluated by counting acellular capillaries in the trypsin digested retinal vasculature and by fluorescein angiography.

RESULTS

Homocysteine, in high glucose medium, exacerbated mitochondrial ROS production, mtDNA damage and impaired mitochondrial respiration within 24 h, and slowed down/worsened mitochondrial biogenesis and mitophagy, as compared to 48 to 96 h in high glucose alone. GYY4137 supplementation ameliorated homocysteine + high glucose-induced mitochondrial damage and impairment in biogenesis and mitophagy. Similar results were obtained from Cbs+/- mice-mitochondrial ROS, mtDNA damage and decline in biogenesis and mitophagy were observed within eight weeks of diabetes vs. 16 to 24 weeks of diabetes in Cbs+/+ mice, and at 24 weeks of diabetes, Cbs+/- mice had significantly higher acellular capillaries and vascular leakage.

CONCLUSIONS

Hyperhomocysteinemia, in a hyperglycemic environment, overwhelms the mitochondria, accelerating and exacerbating their dysfunction, and also delays/worsens their removal, augmenting the development of diabetic retinopathy. Thus, our results strengthen the importance of maintaining homocysteine-hydrogen sulfide balance during the early stages of diabetes for a patient to prevent/retard vision loss.

A novel gene signature related to focal adhesions for distinguishing and predicting the prognosis of lung squamous cell carcinoma

Background

Lung squamous cell carcinoma (LUSC) is a devastating and difficult-to-treat type of lung cancer, and the prognosis of LUSC is the worst. The functional roles of focal adhesion-related genes were explored in LUSC based on data from The Cancer Genome Atlas (TCGA).

Methods

RNA sequencing data and clinical characteristics of LUSC patients in TCGA-LUSC were obtained from the TCGA database. Through systematic analysis, we screened the prognostic genes and determined the focal adhesion-related pathways closely associated with LUSC.

Results

We identified 444 prognostic genes and focal adhesion-related pathways intimately associated with LUSC. According to the focal adhesion-related genes, TCGA-LUSC patients were well divided into two groups: the low-risk group (G1) and the high-risk group (G2). A differential expression analysis identified 44 differentially expressed genes (DEGs) upregulated in the low-risk G1 group and 379 DEGs upregulated in the high-risk G2 group. The upregulated DEGs in the G1 group were primarily related to tyrosine metabolism, steroid hormone biosynthesis, retinol metabolism, platinum drug resistance, pentose and glucuronate interconversions, and metabolism of xenobiotics by cytochrome P450, while the downregulated DEGs in the G1 group were primarily related to ECM-receptor interaction, focal adhesion, proteoglycans in cancer, small cell lung cancer, cytokine-cytokine receptor interaction, and TGF-beta signaling pathway. The immune activity of the G1 group was lower than that of the G2 group, and the half-maximal inhibitory concentration (IC50) of five chemotherapy drugs (i.e., gemcitabine, methotrexate, vinorelbine, paclitaxel, and cisplatin) was significantly different between the G1 and G2 groups. Furthermore, a 10-gene prognostic model was constructed to predict the prognosis for LUSC patients: ITGA3, VAV2, FLNC, FLT4, HGF, MYL2, ITGB1, PDGFRA, CCND2, and PPP1CB.

Conclusion

The status of focal adhesion-related genes has a close relationship with tumor classification and immunity in LUSC patients. A novel focal adhesion-related signature had good prognostic and predictive performance for LUSC. Our findings may provide new insight into the diagnosis and treatment of LUSC.

The nascent polypeptide-associated complex subunit Egd1 is required for efficient selective mitochondrial degradation in budding yeast

Selective degradation of dysfunctional or excess mitochondria is a fundamental process crucial for cell homeostasis in almost all eukaryotes. This process relies on autophagy, an intracellular self-eating system conserved from yeast to humans and is thus called mitophagy. Detailed mechanisms of mitophagy remain to be fully understood. Here we show that mitochondrial degradation in budding yeast, which requires the pro-mitophagic protein Atg32, is strongly reduced in cells lacking Egd1, a beta subunit of the nascent polypeptide-associated complex acting in cytosolic ribosome attachment and protein targeting to mitochondria. By contrast, loss of the sole alpha subunit Egd2 or the beta subunit paralogue Btt1 led to only a partial or slight reduction in mitophagy. We also found that phosphorylation of Atg32, a crucial step for priming mitophagy, is decreased in the absence of Egd1. Forced Atg32 hyperphosphorylation almost completely restored mitophagy in egd1-null cells. Together, we propose that Egd1 acts in Atg32 phosphorylation to facilitate mitophagy.

Role of Autophagy and Mitophagy in Neurodegenerative Disorders

Autophagy is a self-destructive cellular process that removes essential metabolites and waste from inside the cell to maintain cellular health. Mitophagy is the process by which autophagy causes disruption inside mitochondria and the total removal of damaged or stressed mitochondria, hence enhancing cellular health. The mitochondria are the powerhouses of the cell, performing essential functions such as ATP (adenosine triphosphate) generation, metabolism, Ca2+ buffering, and signal transduction. Many different mechanisms, including endosomal and autophagosomal transport, bring these substrates to lysosomes for processing. Autophagy and endocytic processes each have distinct compartments, and they interact dynamically with one another to complete digestion. Since mitophagy is essential for maintaining cellular health and using genetics, cell biology, and proteomics techniques, it is necessary to understand its beginning, particularly in ubiquitin and receptor-dependent signalling in injured mitochondria. Despite their similar symptoms and emerging genetic foundations, Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) have all been linked to abnormalities in autophagy and endolysosomal pathways associated with neuronal dysfunction. Mitophagy is responsible for normal mitochondrial turnover and, under certain physiological or pathological situations, may drive the elimination of faulty mitochondria. Due to their high energy requirements and post-mitotic origin, neurons are especially susceptible to autophagic and mitochondrial malfunction. This article focused on the importance of autophagy and mitophagy in neurodegenerative illnesses and how they might be used to create novel therapeutic approaches for treating a wide range of neurological disorders.

Mitochondrial dynamics as a novel treatment strategy for triple-negative breast cancer

INTRODUCTION

Triple-negative breast cancer (TNBC), recognized as the most heterogeneous type of breast cancer (BC), exhibits a worse prognosis than other subtypes. Mitochondria dynamics play a vital role as mediators in tumorigenesis by adjusting to the cell microenvironments. However, the relationship between mitochondrial dynamics and metabophenotype exhibits discrepancies and divergence across various research and BC models. Therefore, this study aims to explore the role of mitochondrial dynamics in TNBC drug resistance and tumorigenesis.

METHODS

The Wst-8 test was conducted to assess doxorubicin sensitivity in HCC38, MDA-MB-231 (TNBC), and MCF-7 (luminal). Confocal microscopy and FACS were used to quantify the mitochondrial membrane potential (ΔφM), mitophagy, and reactive oxygen species (ROS) production. Agilent Seahorse XF Analyzer was utilized to measure metabolic characteristics. Dynamin-related protein-1 (DRP1), Parkin, and p62 immunohistochemistry staining were performed using samples from 107 primary patients with BC before and after neoadjuvant chemotherapy (NAC).

RESULTS

MDA-MB-231, a TNBC cell line with reduced sensitivity to doxorubicin, reduced ΔφM, and enhanced mitophagy to maintain ROS production through oxidative phosphorylation (OXPHOS)-based metabolism. HCC38, a doxorubicin-sensitive cell line, exhibited no alterations in ΔφM or mitophagy. However, it demonstrated an increase in ROS production and glycolysis. Clinicopathological studies revealed that pretreatment (before NAC) expression of DRP1 was significant in TNBC, as was pretreatment expression of Parkin in the hormone receptor-negative group. Furthermore, low p62 levels seem to be a risk factor for recurrence-free survival.

CONCLUSION

Our findings indicated that the interplay between mitophagy, linked to a worse clinical prognosis, and OXPHOS metabolism promoted chemotherapy resistance in TNBC. Mitochondrial fission is prevalent in TNBC. These findings suggest that targeting the unique mitochondrial metabolism and dynamics in TNBC may offer a novel therapeutic strategy for patients with TNBC.

Impaired Removal of the Damaged Mitochondria in the Metabolic Memory Phenomenon Associated with Continued Progression of Diabetic Retinopathy

Retinopathy fails to halt even after diabetic patients in poor glycemic control try to institute tight glycemic control, suggesting a "metabolic memory" phenomenon, and the experimental models have demonstrated that mitochondria continue to be damaged/dysfunctional, fueling into the vicious cycle of free radicals. Our aim was to investigate the role of removal of the damaged mitochondria in the metabolic memory. Using human retinal endothelial cells (HRECs), incubated in 20 mM D-glucose for 4 days, followed by 5 mM D-glucose for 4 additional days, mitochondrial turnover, formation of mitophagosome, and mitophagy flux were evaluated. Mitophagy was confirmed in a rat model of metabolic memory where the rats were kept in poor glycemic control (blood glucose ~ 400 mg/dl) for 3 months soon after induction of streptozotocin-induced diabetes, followed by 3 additional months of good control (BG < 150 mg/dl). Reversal of high glucose by normal glucose had no effect on mitochondrial turnover and mitophagosome formation, and mitophagy flux remained compromised. Similarly, 3 months of good glycemic control in rats, which had followed 3 months of poor glycemic control, had no effect on mitophagy flux. Thus, poor turnover/removal of the damaged mitochondria, initiated during poor glycemic control, does not benefit from the termination of hyperglycemic insult, and the damaged mitochondria continue to produce free radicals, suggesting the importance of mitophagy in the metabolic memory phenomenon associated with the continued progression of diabetic retinopathy.

Targeted clearance of mitochondria by an autophagy-tethering compound (ATTEC) and its potential therapeutic effects

Increased mitochondrial damage plays a critical role in many neurodegeneration-related diseases such as Parkinson's disease (PD) and Down syndrome (DS). Thus, enhancement of mitochondrial degradation by small molecule compounds may provide promising new strategies to tackle these diseases. Here, we explored the strategy to induce clearance of mitochondria by targeting them to the autophagy machinery by autophagy-tethering compounds (ATTECs). We provided the proof-of-concept evidence demonstrating that the bifunctional compound (mT1) binding to both the outer mitochondrial membrane protein TSPO and the autophagosome protein LC3B simultaneously may enhance the engulfment of damaged mitochondria by autophagosomes and subsequent autophagic degradation of them. In addition, preliminary experiments suggest that mT1 attenuated disease-relevant phenotypes in both a PD cellular model and a DS organoid model. Taken together, we demonstrate the possibility of degrading mitochondria by bifunctional ATTECs, which confirms the capability of degrading organelles by ATTECs and provides potential new strategies in the intervention of mitochondria-related disorders.

Deubiquitinases in cancer

Ubiquitination is an essential regulator of most, if not all, signalling pathways, and defects in cellular signalling are central to cancer initiation, progression and, eventually, metastasis. The attachment of ubiquitin signals by E3 ubiquitin ligases is directly opposed by the action of approximately 100 deubiquitinating enzymes (DUBs) in humans. Together, DUBs and E3 ligases coordinate ubiquitin signalling by providing selectivity for different substrates and/or ubiquitin signals. The balance between ubiquitination and deubiquitination is exquisitely controlled to ensure properly coordinated proteostasis and response to cellular stimuli and stressors. Not surprisingly, then, DUBs have been associated with all hallmarks of cancer. These relationships are often complex and multifaceted, highlighted by the implication of multiple DUBs in certain hallmarks and by the impact of individual DUBs on multiple cancer-associated pathways, sometimes with contrasting cancer-promoting and cancer-inhibiting activities, depending on context and tumour type. Although it is still understudied, the ever-growing knowledge of DUB function in cancer physiology will eventually identify DUBs that warrant specific inhibition or activation, both of which are now feasible. An integrated appreciation of the physiological consequences of DUB modulation in relevant cancer models will eventually lead to the identification of patient populations that will most likely benefit from DUB-targeted therapies.

The role of mitochondrial dynamics in disease

Mitochondria are multifaceted and dynamic organelles regulating various important cellular processes from signal transduction to determining cell fate. As dynamic properties of mitochondria, fusion and fission accompanied with mitophagy, undergo constant changes in number and morphology to sustain mitochondrial homeostasis in response to cell context changes. Thus, the dysregulation of mitochondrial dynamics and mitophagy is unsurprisingly related with various diseases, but the unclear underlying mechanism hinders their clinical application. In this review, we summarize the recent developments in the molecular mechanism of mitochondrial dynamics and mitophagy, particularly the different roles of key components in mitochondrial dynamics in different context. We also summarize the roles of mitochondrial dynamics and target treatment in diseases related to the cardiovascular system, nervous system, respiratory system, and tumor cell metabolism demanding high-energy. In these diseases, it is common that excessive mitochondrial fission is dominant and accompanied by impaired fusion and mitophagy. But there have been many conflicting findings about them recently, which are specifically highlighted in this view. We look forward that these findings will help broaden our understanding of the roles of the mitochondrial dynamics in diseases and will be beneficial to the discovery of novel selective therapeutic targets.

Unraveling the Intricacies of Autophagy and Mitophagy: Implications in Cancer Biology

Autophagy is an essential lysosome-mediated degradation pathway that maintains cellular homeostasis and viability in response to various intra- and extracellular stresses. Mitophagy is a type of autophagy that is involved in the intricate removal of dysfunctional mitochondria during conditions of metabolic stress. In this review, we describe the multifaceted roles of autophagy and mitophagy in normal physiology and the field of cancer biology. Autophagy and mitophagy exhibit dual context-dependent roles in cancer development, acting as tumor suppressors and promoters. We also discuss the important role of autophagy and mitophagy within the cancer microenvironment and how autophagy and mitophagy influence tumor host-cell interactions to overcome metabolic deficiencies and sustain the activity of cancer-associated fibroblasts (CAFs) in a stromal environment. Finally, we explore the dynamic interplay between autophagy and the immune response in tumors, indicating their potential as immunomodulatory targets in cancer therapy. As the field of autophagy and mitophagy continues to evolve, this comprehensive review provides insights into their important roles in cancer and cancer microenvironment.

Roles of mitochondrial dynamics and mitophagy in diabetic myocardial microvascular injury

Myocardial microvessels are composed of a monolayer of endothelial cells, which play a crucial role in maintaining vascular barrier function, luminal latency, vascular tone, and myocardial perfusion. Endothelial dysfunction is a key factor in the development of cardiac microvascular injury and diabetic cardiomyopathy. In addition to their role in glucose oxidation and energy metabolism, mitochondria also participate in non-metabolic processes such as apoptosis, intracellular ion handling, and redox balancing. Mitochondrial dynamics and mitophagy are responsible for regulating the quality and quantity of mitochondria in response to hyperglycemia. However, these endogenous homeostatic mechanisms can both preserve and/or disrupt non-metabolic mitochondrial functions during diabetic endothelial damage and cardiac microvascular injury. This review provides an overview of the molecular features and regulatory mechanisms of mitochondrial dynamics and mitophagy. Furthermore, we summarize findings from various investigations that suggest abnormal mitochondrial dynamics and defective mitophagy contribute to the development of diabetic endothelial dysfunction and myocardial microvascular injury. Finally, we discuss different therapeutic strategies aimed at improving endothelial homeostasis and cardiac microvascular function through the enhancement of mitochondrial dynamics and mitophagy.

Parkin enhances sensitivity of paclitaxel to nasopharyngeal carcinoma by activating BNIP3/NIX-mediated mitochondrial autophagy

As a malignant head and neck cancer, nasopharyngeal carcinoma (NPC) has high morbidity. Parkin expression has been reported to be reduced in NPC tissues and its upregulation could enhance paclitaxel-resistant cell cycle arrest. This study was performed to explore the possible mechanism of Parkin related to B-cell lymphoma-2 (Bcl-2)/adenovirus E1B 19 kDa interacting protein 3 (BNIP3)/BNIP3-like (NIX)-mediated mitochondrial autophagy in NPC cells. Initially, after Parkin overexpression or silencing, cell viability and proliferation were evaluated by lactate dehydrogenase and colony formation assays. JC-1 staining was used to assess the mitochondrial membrane potential. In addition, the levels of cellular reactive oxygen species (ROS) and mitochondrial ROS were detected using DCFH-DA staining and mitochondrial ROS (MitoSOX) red staining. The expression of proteins was measured using Western blot. Results showed that Parkin overexpression inhibited, whereas Parkin knockdown promoted the proliferation of paclitaxel-treated NPC cells. Besides, Parkin overexpression induced, whereas Parkin knockdown inhibited mitochondrial apoptosis in paclitaxel-treated NPC cells, as evidenced by the changes of Cytochrome C (mitochondria), Cytochrome C (cytoplasm), BAK, and Bcl-2 expression. Moreover, the levels of ROS, mitochondrial membrane potential, and LC3II/LC3I in paclitaxel-treated C666-1 cells were hugely elevated by Parkin overexpression and were all declined by Parkin knockdown in CNE-3 cells. Furthermore, Parkin upregulation activated, whereas Parkin downregulation inactivated BNIP3/NIX signaling. Further, BNIP3 silencing or overexpression reversed the impacts of Parkin upregulation or downregulation on the proliferation and mitochondrial apoptosis of paclitaxel-treated NPC cells. Particularly, Mdivi-1 (mitophagy inhibitor) or rapamycin (an activator of autophagy) exerted the same effects on NPC cells as BNIP3 silencing or overexpression, respectively. Collectively, Parkin overexpression activated BNIP3/NIX-mediated mitochondrial autophagy to enhance sensitivity to paclitaxel in NPC.

Function, mechanism and drug discovery of ubiquitin and ubiquitin-like modification with multiomics profiling for cancer therapy

Ubiquitin (Ub) and ubiquitin-like (Ubl) pathways are critical post-translational modifications that determine whether functional proteins are degraded or activated/inactivated. To date, >600 associated enzymes have been reported that comprise a hierarchical task network (e.g., E1-E2-E3 cascade enzymatic reaction and deubiquitination) to modulate substrates, including enormous oncoproteins and tumor-suppressive proteins. Several strategies, such as classical biochemical approaches, multiomics, and clinical sample analysis, were combined to elucidate the functional relations between these enzymes and tumors. In this regard, the fundamental advances and follow-on drug discoveries have been crucial in providing vital information concerning contemporary translational efforts to tailor individualized treatment by targeting Ub and Ubl pathways. Correspondingly, emphasizing the current progress of Ub-related pathways as therapeutic targets in cancer is deemed essential. In the present review, we summarize and discuss the functions, clinical significance, and regulatory mechanisms of Ub and Ubl pathways in tumorigenesis as well as the current progress of small-molecular drug discovery. In particular, multiomics analyses were integrated to delineate the complexity of Ub and Ubl modifications for cancer therapy. The present review will provide a focused and up-to-date overview for the researchers to pursue further studies regarding the Ub and Ubl pathways targeted anticancer strategies.

Machine learning and single-cell sequencing reveal the potential regulatory factors of mitochondrial autophagy in the progression of gastric cancer

BACKGROUND

As an important regulatory mechanism to remove damaged mitochondria and maintain the balance between internal and external cells, mitochondrial autophagy plays a key role in the progression and treatment of cancer Onishi (EMBO J 40(3): e104705, 2021). The purpose of this study is to comprehensively analyze the role of mitochondrial autophagy-related genes in the progression of gastric cancer (GC) by RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq).

METHODS

GSE26942, GSE54129,GSE66229,GSE183904 and other data sets were obtained by GEO databases. Using support vector machine recursive feature elimination (SVM-RVF) algorithm and random forest algorithm, the mitochondrial autophagy-related genes related to gastric cancer were obtained, respectively. After that, the model was constructed and the inflammatory factors, immune score and immune cell infiltration were analyzed. Furthermore, according to the scRNA-seq data of 28,836 cells from 13 GC samples, 18 cell clusters and 7 cell types were identified by scRNA-seq analysis. The expression level and signal pathway of related genes were verified by cell communication analysis. Finally, the regulatory network of cells was analyzed by SCENIC.

RESULTS

MAP1LC3B, PGAW5, PINK1, TOMM40 and UBC are identified as key genes through machine learning algorithms. CXCL12-CXCR4, LGALS9-CD44, LGALS9-CD45 and MIF (CD74 + CD44) pathways may play an important role in endothelial cells with high score scores of T cells and monocytes in tumor environment. CEBPB, ETS1, GATA2, MATB, SPl1 and XBP1 were identified as candidate TF with specific regulatory expression in the GC cell cluster.

CONCLUSION

The results of this study will provide implications for the study of the mechanism, diagnosis and treatment of mitochondrial autophagy in GC.

Parkin regulates IGF2BP3 through ubiquitination in the tumourigenesis of cervical cancer

BACKGROUND

Insulin-like growth Factor 2 mRNA-binding protein 3 (IGF2BP3) is a highly conserved RNA-binding protein and plays a critical role in regulating posttranscriptional modifications.

METHODS

Immunoprecipitation was used to examine the interaction of Parkin and IGF2BP3. Mass spectrometry was performed to identify the ubiquitination sites of IGF2BP3. RNA-immunoprecipitation was conducted to examine the target genes of IGF2BP3. Xenograft mouse model was constructed to determine the tumorigenesis of IGF2BP3.

RESULTS

IGF2BP3 expression is negatively correlated with Parkin expression in human cervical cancer cells and tissues. Parkin directly interacts with IGF2BP3, and overexpression of Parkin causes the proteasomal degradation of IGF2BP3, while knockdown of PARK2 increases the protein levels of IGF2BP3. Mechanistically, in vivo and in vitro ubiquitination assays demonstrated that Parkin is able to ubiquitinate IGF2BP3. Moreover, the ubiquitination site of IGF2BP3 was identified at K213 in the first KH domain of IGF2BP3. IGF2BP3 mutation results in the loss of its oncogenic function as an m6A reader, resulting in the inactivation of the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signalling pathways. In addition, IGF2BP3 mutation results in the attenuation of Parkin-mediated mitophagy, indicating its inverse role in regulating Parkin. Consequently, the tumourigenesis of cervical cancer is also inhibited by IGF2BP3 mutation.

CONCLUSION

IGF2BP3 is ubiquitinated and regulated by the E3 ubiquitin ligase Parkin in human cervical cancer and ubiquitination modification plays an important role in modulating IGF2BP3 function. Thus, understanding the role of IGF2BP3 in tumourigenesis could provide new insights into cervical cancer therapy.

Ionizing radiation triggers mitophagy to enhance DNA damage in cancer cells

Radiotherapy is an important cancer treatment strategy that causes DNA damage in tumor cells either directly or indirectly. Autophagy is a physiological process linked to DNA damage. Mitophagy is a form of autophagy, which specifically targets and eliminates impaired mitochondria, thereby upholding cellular homeostasis. However, the connection between DNA damage and mitophagy has yet to be fully elucidated. We found that mitophagy, as an upstream signal, increases ionizing radiation-induced DNA damage by downregulating or overexpressing key mitophagy proteins Parkin and BNIP3. Enhancing the basal level of mitophagy in conjunction with X-ray irradiation can potentially diminish cell cycle arrest at the G2/M phase, substantially elevate the accumulation of γ-H2AX, 53BP1, and PARP1 foci within the nucleus, augment DNA damage, and facilitate the demise of tumor cells. Consequently, this approach prolongs the survival of melanoma-bearing mice. The findings of this study are anticipated to offer a therapeutic approach for enhancing the therapeutic effectiveness of radiotherapy.

Adult IDH Wild-Type Glioblastoma Ultrastructural Investigation Suggests a Possible Correlation between Morphological Biomarkers and Ki-67 Index

Glioblastoma is an aggressive brain tumor with an average life expectancy between 14 and 16 months after diagnosis. The Ki-67 labeling index (LI), a measure of cellular proliferation, is emerging as a prognostic marker in GBM. In this study, we investigated the ultrastructure of glioblastoma tissue from 9 patients with the same molecular profile (adult IDH wild-type glioblastoma, wild-type ATRX, and positive for TP53 expression, GFAP expression, and EGFR overexpression) to find possible ultrastructural features to be used as biomarkers and correlated with the only parameter that differs among our samples, the Ki-67 LI. Our main results were the visualization of the anatomical basis of astrocyte-endothelial cells crosstalk; the ultrastructural in situ imaging of clusters of hyperactivated microglia cells (MsEVs); the ultrastructural in situ imaging of microglia cells storing lipid vesicles (MsLVs); the ultrastructural in situ imaging of neoplastic cells mitophagy (NCsM). The statistical analysis of our data indicated that MsEVs and MsLVs correlate with the Ki-67 LI value. We can thus assume they are good candidates to be considered morphological biomarkers correlating to Ki-67 LI. The role of NCsM instead must be further evaluated. Our study findings demonstrate that by combining ultrastructural characteristics with molecular information, we can discover biomarkers that have the potential to enhance diagnostic precision, aid in treatment decision-making, identify targets for therapy, and enable personalized treatment plans tailored to each patient. However, further research with larger sample sizes is needed to validate these findings and fully utilize the potential of ultrastructural analysis in managing glioblastoma.

Mitophagy-mediated inflammation and oxidative stress contribute to muscle wasting in cancer cachexia

Cancer cachexia is commonly seen in patients with malignant tumors, which usually leads to poor life quality and negatively affects long-term prognosis and survival. Mitochondria dysfunction and enhanced autophagy are well-established to play an important role in skeletal muscle wasting. However, whether mitophagy is engaged in the pathogenesis of cancer cachexia requires further investigation. This study comprised a clinical study and animal experimentation. Clinical data such as CT images and laboratory results were obtained and analyzed. Then mice model of cancer cachexia and mitophagy inhibition were established. Data including skeletal muscle mass and function, mitochondria structure and function, inflammatory factors as well as ROS concentration. Mitophagy was enhanced in cancer cachexia patients with increased inflammatory factors. Greater disruption of skeletal muscle fiber and mitochondria structure were seen in cancer cachexia, with a higher level of inflammatory factors and ROS expression in skeletal muscle. Meanwhile, ATP production was undermined, indicating a close relationship with mitophagy, inflammation, and oxidative stress in the skeletal muscle of cancer cachexia mice models. In conclusion, mitophagy is activated in cancer cachexia and may play a role in skeletal muscle atrophy, and inflammation and oxidative stress might participate in mitophagy-related skeletal muscle injury.

Advances in mitophagy and mitochondrial apoptosis pathway-related drugs in glioblastoma treatment

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system (CNS). It is a leading cause of death among patients with intracranial malignant tumors. GBM exhibits intra- and inter-tumor heterogeneity, leading to drug resistance and eventual tumor recurrence. Conventional treatments for GBM include maximum surgical resection of glioma tissue, temozolomide administration, and radiotherapy, but these methods do not effectively halt cancer progression. Therefore, development of novel methods for the treatment of GBM and identification of new therapeutic targets are urgently required. In recent years, studies have shown that drugs related to mitophagy and mitochondrial apoptosis pathways can promote the death of glioblastoma cells by inducing mitochondrial damage, impairing adenosine triphosphate (ATP) synthesis, and depleting large amounts of ATP. Some studies have also shown that modern nano-drug delivery technology targeting mitochondria can achieve better drug release and deeper tissue penetration, suggesting that mitochondria could be a new target for intervention and therapy. The combination of drugs targeting mitochondrial apoptosis and autophagy pathways with nanotechnology is a promising novel approach for treating GBM.This article reviews the current status of drug therapy for GBM, drugs targeting mitophagy and mitochondrial apoptosis pathways, the potential of mitochondria as a new target for GBM treatment, the latest developments pertaining to GBM treatment, and promising directions for future research.