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1.
Cell Rep Med ; : 101531, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697105

RESUMO

The clinical applications of immunocytokines are severely restricted by dose-limiting toxicities. To address this challenge, here we propose a next-generation immunocytokine concept involving the design of LH05, a tumor-conditional anti-PD-L1/interleukin-15 (IL-15) prodrug. LH05 innovatively masks IL-15 with steric hindrance, mitigating the "cytokine sink" effect of IL-15 and reducing systemic toxicities associated with wild-type anti-PD-L1/IL-15. Moreover, upon specific proteolytic cleavage within the tumor microenvironment, LH05 releases an active IL-15 superagonist, exerting potent antitumor effects. Mechanistically, the antitumor efficacy of LH05 depends on the increased infiltration of CD8+ T and natural killer cells by stimulating the chemokines CXCL9 and CXCL10, thereby converting cold tumors into hot tumors. Additionally, the tumor-conditional anti-PD-L1/IL-15 can synergize with an oncolytic virus or checkpoint blockade in advanced and metastatic tumor models. Our findings provide a compelling proof of concept for the development of next-generation immunocytokines, contributing significantly to current knowledge and strategies of immunotherapy.

2.
Autophagy ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705725

RESUMO

Macroautophagy/autophagy is a catabolic process crucial for degrading cytosolic components and damaged organelles to maintain cellular homeostasis, enabling cells to survive in extreme extracellular environments. ENAH/MENA, a member of the Ena/VASP protein family, functions as a highly efficient actin elongation factor. In this study, our objective was to explore the role of ENAH in the autophagy process. Initially, we demonstrated that depleting ENAH in cancer cells inhibits autophagosome formation. Subsequently, we observed ENAH's colocalization with MAP1LC3/LC3 during tumor cell starvation, dependent on actin cytoskeleton polymerization and the interaction between ENAH and BECN1 (beclin 1). Additionally, mammalian ATG9A formed a ring-like structure around ENAH-LC3 puncta during starvation, relying on actin cytoskeleton polymerization. Furthermore, ENAH's EVH1 and EVH2 domains were found to be indispensable for its colocalization with LC3 and BECN1, while the PRD domain played a crucial role in the formation of the ATG9A ring. Finally, our study revealed ENAH-led actin comet tails in autophagosome trafficking. In conclusion, our findings provide initial insights into the regulatory role of the mammalian actin elongation factor ENAH in autophagy.

3.
Sci Rep ; 14(1): 8201, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589634

RESUMO

The α-tubulin subtype, Tubulin α-1b chain (TUBA1B), has been shown to influence immune cell infiltration, cancer growth, and survival across various malignancies. However, a comprehensive study has not yet been undertaken examining the immunological and predictive effects of TUBA1B in a pan-carcinoma context. Using data from TCGA, GEO, and other databases, we analyzed TUBA1B expression across various carcinoma types using transcriptional profiling, prognostic implications, genetic and epigenetic alterations, methylation patterns, and immunological significance. To validate our findings, we conducted Western blot analysis to assess TUBA1B protein levels in matched breast cancer tissue samples and performed CCK-8 proliferation assay, flow cytometry, transwell invasion, and migration assays to comprehensively examine the functional impact of TUBA1B on breast cancer cells. Our pan-cancer analysis found TUBA1B upregulation across most tumor types, with varying expression patterns in distinct immune and molecular subtypes. High TUBA1B expression was an independent risk factor and associated with poor prognoses in several cancers, including BRCA, KICH, LGG, LUAD, and MESO. TUBA1B also demonstrates moderate to high diagnostic accuracy in most tumor types. Increased m6A methylation levels were observed in the TUBA1B gene, while its promoter region displayed low methylation levels. TUBA1B's expression impacted some cancers by elevating tumor mutation burden, microsatellite instability, neoantigen formation, immune cell infiltration, and the modulation of immune checkpoints. Functional enrichment analysis highlights TUBA1B's involvement in important cellular processes such as the cell cycle, p53 signaling, cell senescence, programmed cell death, and the regulation of immune-related pathways. Moreover, our study reveals higher TUBA1B protein expression in breast cancer tissues compared to adjacent tissues. In vitro experiments confirm that TUBA1B deletion reduces breast cancer cell proliferation, invasion, and migration while increasing apoptosis. In conclusion, our study suggests that TUBA1B could potentially serve as a diagnostic marker for predicting cancer immunological profiles and survival outcomes and shed light on the expression and role of TUBA1B in breast cancer, providing a solid foundation for considering it as a promising therapeutic target for breast cancer patient treatment.


Assuntos
Neoplasias da Mama , Carcinoma , Humanos , Feminino , Neoplasias da Mama/genética , Tubulina (Proteína)/genética , Prognóstico , Biomarcadores
4.
ACS Nano ; 18(15): 10495-10508, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38556991

RESUMO

Sonodynamic therapy (SDT) has promising application prospects in tumor therapy. However, SDT does not eradicate metastatic tumors. Herein, Cu-substituted ZnAl ternary layered double hydroxide nanosheets (ZCA NSs) were developed as both sonosensitizers and copper nanocarriers for synergistic SDT/cuproptosis cancer therapy. An optimized electronic structure more conducive to the sonodynamic process was obtained from ZCA NSs via the Jahn-Teller effect induced by the introduction of Cu2+, and the synthesized ZCA NSs regulated the intricate tumor microenvironment (TME) by depleting endogenous glutathione (GSH) to amplify oxidative stress for further enhanced SDT performance. Furthermore, cuproptosis was evoked by intracellular overload of Cu2+ and amplified by SDT, leading to irreversible proteotoxicity. In vitro results showed that such synergetic SDT/cuproptosis triggered immunogenic cell death (ICD) and promoted the maturation of dendritic cells (DCs). Furthermore, the as-synthesized ZCA NS-mediated SDT/cuproptosis thoroughly eradicated the in vivo solid tumors and simultaneously elicited antitumor immunity to suppress lung and liver metastasis. Overall, this work established a nanoplatform for synergistic SDT/cuproptosis with a satisfactory antitumor immunity.


Assuntos
Neoplasias Hepáticas , Neoplasias , Terapia por Ultrassom , Humanos , Cobre , Eletrônica , Glutationa , Hidróxidos , Neoplasias Hepáticas/tratamento farmacológico , Imunidade , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Microambiente Tumoral
5.
ACS Nano ; 18(16): 10885-10901, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38587876

RESUMO

Hypochlorous acid (HClO), as a powerful oxidizer, is obtained from the oxidation of Cl- ions during the electrochemical therapy (EChT) process for cancer therapy. However, the extracellular generated HClO is inadequate to inhibit effective tumor cell death. Herein, manganese-doped potassium chloride nanocubes (MPC NCs) fabricated and modified with amphipathic polymer PEG (PMPC NCs) to function as massive three-dimensional nanoelectrodes (NEs) were developed to enhance the generation of HClO for electrochemical immunotherapy under an alternating electric field. Under an square-wave alternating current (AC) electric field, the generation of HClO was boosted by PMPC NEs due to the enlarged active surface area, enhanced mass transfer rate, and improved electrocatalytic activity. Notably, PMPC NEs upregulated the intracellular HClO concentration to induce robust immunogenic cell death (ICD) under an AC electric field. Meanwhile, the electric-triggered release of Mn2+ effectively stimulated dendritic cells (DCs) maturation. In vivo results illustrated that PMPC-mediated EChT inhibited tumor growth and triggered the promotion of the immune response to regulate the tumor immune microenvironment. Based on the potent antitumor immunity, PMPC-mediated EChT was further combined with an immune checkpoint inhibitor (αCTLA-4) to realize combined EChT-immunotherapy, which demonstrated enhanced tumor inhibition of the primary tumors and an abscopal effect on distant tumors. To summarize, our work highlights the application of electrochemical-immunotherapy technology in tumor therapy.


Assuntos
Imunoterapia , Manganês , Manganês/química , Camundongos , Animais , Eletrodos , Humanos , Técnicas Eletroquímicas , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C
6.
Medicine (Baltimore) ; 103(17): e37916, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669419

RESUMO

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors with diverse clinical presentations. Alterations in energy expenditure state are commonly observed in patients with PPGL. However, the reported prevalence of hypermetabolism varies significantly and the underlying mechanisms and implications of this presentation have not been well elucidated. This review discusses and analyzes the factors that contribute to energy consumption. Elevated catecholamine levels in patients can significantly affect substance and energy metabolism. Additionally, changes in the activation of brown adipose tissue (BAT), inflammation, and the inherent energy demands of the tumor can contribute to increased resting energy expenditure (REE) and other energy metabolism indicators. The PPGL biomarker, chromogranin A (CgA), and its fragments also influence energy metabolism. Chronic hypermetabolic states may be detrimental to these patients, with surgical tumor removal remaining the primary therapeutic intervention. The high energy expenditure of PPGL has not received the attention it deserves, and an accurate assessment of energy metabolism is the cornerstone for an adequate understanding and treatment of the disease.


Assuntos
Neoplasias das Glândulas Suprarrenais , Metabolismo Energético , Paraganglioma , Feocromocitoma , Humanos , Metabolismo Energético/fisiologia , Feocromocitoma/metabolismo , Paraganglioma/metabolismo , Neoplasias das Glândulas Suprarrenais/metabolismo , Catecolaminas/metabolismo , Tecido Adiposo Marrom/metabolismo , Cromogranina A/metabolismo
7.
J Mol Neurosci ; 74(1): 30, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478195

RESUMO

Microglia are resident macrophages within the central nervous system, serving as the first responders to neuroinflammation. Glucocorticoids (GCs) may cause damage to brain tissue, but the specific mechanism remains unclear. This study was divided into two parts: a glucocorticoid receptor (GR) mitochondrial translocation intervention experiment and a mitochondrial oxidative stress inhibition experiment. BV-2 microglia were stimulated with dexamethasone (DEX) and treated with either tubastatin-A or mitoquinone (MitoQ) for 24 h. Our results showed that DEX increased the translocation of GRs to mitochondria, and this effect was accompanied by decreases in the expression of mitochondrially encoded cytochrome c oxidase 1 (MT-CO1) and mitochondrially encoded cytochrome c oxidase 3 (MT-CO3) and increases in the expression of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), caspase-1, and Gasdermin D (GSDMD). The level of mitochondrial respiratory chain complex IV (MRCC IV) and adenosine triphosphate (ATP) was decreased. An elevation in the level of mitochondrial oxidative stress and the opening of the mitochondrial permeability transition pore (mPTP) was also observed. Mechanistically, tubastatin-A significantly suppressed the mitochondrial translocation of GRs, improved the expression of mitochondrial genes, promoted the restoration of mitochondrial function, and inhibited pyroptosis. MitoQ significantly prevented mitochondrial oxidative stress, improved mitochondrial function, and reduced apoptosis and pyroptosis. Both tubastatin-A and MitoQ suppressed DEX-induced pyroptosis. This study substantiates that the increase in the mitochondrial translocation of GRs mediated by GCs exacerbates oxidative stress and pyroptosis in microglia, which indicates that the regulation of mitochondrial pathways by GCs is pathogenic to microglia.


Assuntos
Glucocorticoides , Piroptose , Glucocorticoides/farmacologia , Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Microglia/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Estresse Oxidativo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
8.
Ann Hematol ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459154

RESUMO

Histological transformation into an aggressive B-cell lymphoma indicates a poor survival outcome for patients with indolent marginal zone lymphoma (MZL), which has been less studied. Large-scale data with long-term follow-up to investigate MZL transformation is limited. Here, by reporting a US-Nationwide cohort of 30,619 MZL patients diagnosed between 2000 and 2019, we found that transformation occurred in 2.08% (N = 624) of MZL cases, with the transformation incidence of 3.1 per 1,000 person-years. Advanced Ann Arbor stage, nodal MZL (NMZL) and splenic MZL (SMZL) were associated with an elevated risk of transformation. Certain subtype-specific characteristics, such as non-gastric extra-nodal MZL (vs. gastric, HR, 1.51, 95%CI 1.13-2.04; p = 0.006), and receiving splenectomy for SMZL (HR, 2.04, 95%CI 1.28-3.26; p = 0.003), also indicated a higher risk of transformation. Besides, transformation independently increased the overall mortality risk (HR, 1.38, 95%CI 1.24-1.53, p < 0.001), especially the higher lymphoma-caused mortality risk (HR, 3.21, 95%CI 2.81-3.67, p < 0.001). Transformation was also associated with a higher percentage of lymphoma-caused deaths. The post-transformation prognostic analyses demonstrated that female gender and age ≥ 65 years independently affected patients' mortalities. These findings, based on the largest cohort to date, contribute to a better understanding of transformed MZL, and provide valuable reference points for guidelines and patient counseling.

9.
Drug Resist Updat ; 73: 101028, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340425

RESUMO

AIMS: The overexpression of ABC transporters on cancer cell membranes is one of the most common causes of multidrug resistance (MDR). This study investigates the impact of ABCC1 and ABCG2 on the resistance to talazoparib (BMN-673), a potent poly (ADP-ribose) polymerase (PARP) inhibitor, in ovarian cancer treatment. METHODS: The cell viability test was used to indicate the effect of talazoparib in different cell lines. Computational molecular docking analysis was conducted to simulate the interaction between talazoparib and ABCC1 or ABCG2. The mechanism of talazoparib resistance was investigated by constructing talazoparib-resistant subline A2780/T4 from A2780 through drug selection with gradually increasing talazoparib concentration. RESULTS: Talazoparib cytotoxicity decreased in drug-selected or gene-transfected cell lines overexpressing ABCC1 or ABCG2 but can be restored by ABCC1 or ABCG2 inhibitors. Talazoparib competitively inhibited substrate drug efflux activity of ABCC1 or ABCG2. Upregulated ABCC1 and ABCG2 protein expression on the plasma membrane of A2780/T4 cells enhances resistance to other substrate drugs, which could be overcome by the knockout of either gene. In vivo experiments confirmed the retention of drug-resistant characteristics in tumor xenograft mouse models. CONCLUSIONS: The therapeutic efficacy of talazoparib in cancer may be compromised by its susceptibility to MDR, which is attributed to its interactions with the ABCC1 or ABCG2 transporters. The overexpression of these transporters can potentially diminish the therapeutic impact of talazoparib in cancer treatment.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Ftalazinas , Humanos , Animais , Feminino , Camundongos , Ribose/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , Resistencia a Medicamentos Antineoplásicos/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias
10.
Cell Commun Signal ; 22(1): 83, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291473

RESUMO

BACKGROUND: Tumor cells frequently suffer from endoplasmic reticulum (ER) stress. Previous studies have extensively elucidated the role of tumorous unfolded protein response in melanoma cells, whereas the effect on tumor immunology and the underlying mechanism remain elusive. METHODS: Bioinformatics, biochemical assays and pre-clinical mice model were employed to demonstrate the role of tumorous inositol-requiring transmembrane kinase/endoribonuclease 1α (IRE1α) in anti-tumor immunity and the underlying mechanism. RESULTS: We firstly found that IRE1α signaling activation was positively associated with the feature of tumor-infiltrating lymphocytes. Then, pharmacological ER stress induction by HA15 exerted prominent anti-tumor effect in immunocompetent mice and was highly dependent on CD8+T cells, paralleled with the reshape of immune cells in tumor microenvironment via tumorous IRE1α-XBP1 signal. Subsequently, tumorous IRE1α facilitated the expression and secretion of multiple chemokines and cytokines via XBP1-NF-κB axis, leading to increased infiltration and anti-tumor capacity of CD8+T cells. Ultimately, pharmacological induction of tumorous ER stress by HA15 brought potentiated therapeutic effect along with anti-PD-1 antibody on melanoma in vivo. CONCLUSIONS: Tumorous IRE1α facilitates CD8+T cells-dependent anti-tumor immunity and improves immunotherapy efficacy by regulating chemokines and cytokines via XBP1-NF-κB axis. The combination of ER stress inducer and anti-PD-1 antibody could be promising for increasing the efficacy of melanoma immunotherapy.


Assuntos
Melanoma , Animais , Camundongos , Linfócitos T CD8-Positivos/patologia , Quimiocinas , Citocinas , Endorribonucleases , Melanoma/patologia , NF-kappa B , Proteínas Serina-Treonina Quinases/metabolismo , Linfócitos T/metabolismo , Microambiente Tumoral
11.
Artigo em Inglês | MEDLINE | ID: mdl-37961860

RESUMO

BACKGROUND: As the only humanized monoclonal antibody against receptor activator of nuclear factor-κB ligand (RANKL) for giant cell tumour of bone (GCTB) therapy, denosumab has limited antitumour effect on neoplastic stromal cells. Nevertheless, its mechanism of action has not yet been clarified. A previous study has revealed that p62 may play an important role in the antitumour activity of denosumab. OBJECTIVE: The study aimed to investigate if the mechanism by which denosumab inhibits GCTB neoplastic stromal cells growth is via p62 modulation and other related mechanisms. METHODS: p62 expression before and after denosumab therapy was analysed by RT‒qPCR, western blot, ELISA, and immunohistochemical assays. Two primary neoplastic stromal cells were isolated from fresh GCTB tumour tissue (L cell) and metastatic tissue (M cell). Cell proliferation, migration, apoptosis, and autophagy were investigated in p62 knockdown neoplastic stromal cells transfected by short hairpin RNA lentivirus in vitro. Tumor growth was evaluated in the chick chorioallantoic membrane model in vivo. RESULTS: p62 expression was found to be downregulated following denosumab therapy. The patients with a decrease in p62 expression had lower recurrence-free survival rates. The proliferation of M cells was not inhibited by denosumab therapy, but it was restored by p62 knockdown. Moreover, p62 knockdown inhibited tumour growth in vivo. Denosumab induced M cell apoptosis and arrested the cell cycle at the G1/G0 transition and these effects were also enhanced by p62 knockdown. Autophagic flux assays revealed p62 modulation to be dependent on autophagy following denosumab incubation. CONCLUSION: Denosumab induced neoplastic stromal cells apoptosis via p62 downregulation dependent on autophagy pathway. The combination of p62 and RANKL knockdown might be a better strategy than RANKL knockdown alone for GCTB targeted therapy.

12.
Cell Mol Life Sci ; 80(11): 315, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37801083

RESUMO

Melanoma is the most lethal skin cancer originating from the malignant transformation of epidermal melanocyte. The dysregulation of cellular metabolism is a hallmark of cancer, including in melanoma. Aberrant branched-chain amino acids (BCAA) metabolism and related enzymes has been greatly implicated in the progression of multiple types of cancer, whereas remains far from understood in melanoma. Herein, we reported that the critical BCAA metabolism enzyme branched-chain amino acid transaminase 2 (BCAT2) is an oncogenic factor in melanoma by activating lipogenesis via the epigenetic regulation of fatty acid synthase (FASN) and ATP-citrate lyase (ACLY) expressions. Firstly, we found that BCAT2 expression was prominently increased in melanoma, and highly associated with clinical stage. Then, it was proved that the deficiency of BCAT2 led to impaired tumor cell proliferation, invasion and migration in vitro, and tumor growth and metastasis in vivo. Further, RNA sequencing technology and a panel of biochemical assays demonstrated that BCAT2 regulated de novo lipogenesis via the regulation of the expressions of both FASN and ACLY. Mechanistically, the inhibition of BCAT2 suppressed the generation of intracellular acetyl-CoA, mitigating P300-dependent histone acetylation at the promoter of FASN and ACLY, and thereby their transcription. Ultimately, zinc finger E-box binding homeobox 1 (ZEB1) was identified as the upstream transcriptional factor responsible for BCAT2 up-regulation in melanoma. Our results demonstrate that BCAT2 promotes melanoma progression by epigenetically regulating FASN and ACLY expressions via P300-dependent histone acetylation. Targeting BCAT2 could be exploited as a promising strategy to restrain tumor progression in melanoma.


Assuntos
Melanoma , Proteínas da Gravidez , Humanos , Lipogênese/genética , ATP Citrato (pro-S)-Liase/genética , ATP Citrato (pro-S)-Liase/metabolismo , Histonas/metabolismo , Epigênese Genética , Melanoma/genética , Transaminases/genética , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Ácido Graxo Sintase Tipo I/genética
13.
Front Pharmacol ; 14: 1266782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745050

RESUMO

Background: Small cell lung cancer (SCLC) is characterized by extreme invasiveness and lethality. There have been very few developments in its diagnosis and treatment over the past decades. It is urgently needed to explore potential novel biomarkers and drug targets for SCLC. Methods: Two-sample Mendelian Randomization (MR) was performed to investigate causal associations between SCLC and plasma proteins using genome-wide association studies (GWAS) summary statistics of SCLC from Transdisciplinary Research Into Cancer of the Lung Consortium (nCase = 2,791 vs. nControl = 20,580), and was validated in another cohort (nCase = 2,664 vs. nControl = 21,444). 734 plasma proteins and their genetic instruments of cis-acting protein quantitative trait loci (pQTL) were used, whereas external plasma proteome data was retrieved from deCODE database. Bidirectional MR, Steiger filtering and phenotype scanning were applied to further verify the associations. Results: Seven significant (p < 6.81 × 10-5) plasma protein-SCLC pairs were identified by MR analysis, including ACP5 (OR = 0.76, 95% CI: 0.67-0.86), CPB2 (OR = 0.90, 95% CI: 0.86-0.95), GSTM3 (OR = 0.45, 95% CI: 0.33-0.63), SHMT1 (OR = 0.74, 95% CI: 0.64-0.86), CTSB (OR = 0.79, 95% CI: 0.71-0.88), NTNG1 (OR = 0.81, 95% CI: 0.74-0.90) and FAM171B (OR = 1.40, 95% CI: 1.21-1.62). The external validation confirmed that CPB2, GSTM3 and NTNG1 had protective effects against SCLC, while FAM171B increased SCLC risk. However, the reverse causality analysis revealed that SCLC caused significant changes in plasma levels of most of these proteins, including decreases of ACP5, CPB2, GSTM3 and NTNG1, and the increase of FAM171B. Conclusion: This integrative analysis firstly suggested the causal associations between SCLC and plasma proteins, and the identified several proteins may be promising novel drug targets or biomarkers for SCLC.

14.
Nat Struct Mol Biol ; 30(12): 1996-2008, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37696957

RESUMO

Over half of mitochondrial proteins are imported from the cytosol via the pre-sequence pathway, controlled by the TOM complex in the outer membrane and the TIM23 complex in the inner membrane. The mechanisms through which proteins are translocated via the TOM and TIM23 complexes remain unclear. Here we report the assembly of the active TOM-TIM23 supercomplex of Saccharomyces cerevisiae with translocating polypeptide substrates. Electron cryo-microscopy analyses reveal that the polypeptide substrates pass the TOM complex through the center of a Tom40 subunit, interacting with a glutamine-rich region. Structural and biochemical analyses show that the TIM23 complex contains a heterotrimer of the subunits Tim23, Tim17 and Mgr2. The polypeptide substrates are shielded from lipids by Mgr2 and Tim17, which creates a translocation pathway characterized by a negatively charged entrance and a central hydrophobic region. These findings reveal an unexpected pre-sequence pathway through the TOM-TIM23 supercomplex spanning the double membranes of mitochondria.


Assuntos
Proteínas de Membrana Transportadoras , Proteínas de Saccharomyces cerevisiae , Proteínas de Membrana Transportadoras/química , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas de Transporte/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Transporte Proteico , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Mitocondriais/metabolismo , Peptídeos/metabolismo , Proteínas de Membrana/metabolismo
15.
ACS Nano ; 17(17): 17105-17121, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37603593

RESUMO

Bioactive inorganic nanomaterials and the biological effects of metal ions have attracted extensive attention in tumor therapy in recent years. Vanadium (V), as a typical bioactive metal element, regulates a variety of biological functions. However, its role in antitumor therapy remains to be revealed. Herein, biodegradable vanadium disulfide (VS2) nanosheets (NSs) were prepared as a responsive gas donor and bioactive V source for activating cancer immunotherapy in combination with immune-checkpoint blockade therapy. After PEGylation, VS2-PEG exhibited efficient glutathione (GSH) depletion and GSH-activated hydrogen sulfide (H2S) release. Exogenous H2S caused lysosome escape and reduced adenosine triphosphate (ATP) synthesis in tumor cells by interfering with the mitochondrial membrane potential and inducing acidosis. In addition, VS2-PEG degraded into high-valent vanadate, leading to Na+/K+ ATPase inhibition, potassium efflux, and interleukin (IL)-1ß production. Together with further induction of ferroptosis and immunogenic cell death, a strong antitumor immune response was stimulated by reversing the immunosuppressive tumor microenvironment. Moreover, the combined treatment of VS2-PEG and α-PD-1 amplified antitumor therapy, significantly suppressed tumor growth, and further elicited robust immunity to effectively defeat tumors. This work highlights the biological effects of vanadium for application in cancer treatment.


Assuntos
Neoplasias , Vanadatos , Vanadatos/farmacologia , Vanadatos/uso terapêutico , Inibidores de Checkpoint Imunológico , Vanádio , Imunoterapia , Glutationa , Neoplasias/tratamento farmacológico
16.
J Cachexia Sarcopenia Muscle ; 14(5): 2264-2274, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37559425

RESUMO

BACKGROUND: Our study aimed to evaluate change in sarcopenia, its defining components over 1 year follow-up and investigate associations with subsequent cognitive decline, incident mild cognitive impairment (MCI) and dementia among patients undergoing haemodialysis (HD). METHODS: In the multicentre, longitudinal study, 1117 HD patients aged 56.8 ± 14.3 years (654 men; and 463 women) from 17 dialysis centres in Guizhou Province, China, were recruited in 2019 and followed up for 1 year in 2020. Sarcopenia was diagnosed with Asian Working Group for Sarcopenia criteria using appendicular skeletal muscle mass index (ASMI) and handgrip strength (HGS). Body composition was measured using body composition monitor; body water, weight, and height were corrected to calculate ASMI. HGS was measured by mechanical handgrip dynamometer. Cognitive function was measured with Mini Mental State Examination. Multivariate linear, logistic regression models and subgroup analyses were employed to examine the associations of changes in sarcopenia, ASMI, and HGS with Mini Mental State Examination score change, and incident MCI, dementia. RESULTS: Four hundred fourteen (37.1%) patients had sarcopenia at baseline; during 1 year follow-up, 257 (23.0%) developed MCI and 143 (12.8%) developed dementia. According to changes in sarcopenia, patients were stratified into four groups: non-sarcopenia; non-sarcopenia to sarcopenia; sarcopenia; and sarcopenia to non-sarcopenia. HD patients in sarcopenia and non-sarcopenia to sarcopenia groups had higher risk of MCI (34.8%, 32.0%, vs. 17.4%) and dementia (20.6%, 19.8%, vs. 8.7%), compared non-sarcopenia group (P < 0.001). Multivariate linear regression analyses showed that sarcopenia [regression coefficients (ß) -1.098, 95% confidence interval (CI) -1.872, -0.324, P = 0.005] and non-sarcopenia to sarcopenia (ß -1.826, -2.441, -1.212, P < 0.001) were associated with faster cognitive decline compared to non-sarcopenia. HGS decline (ß 0.046, 0.027-0.064, P < 0.001) and ASMI decline (ß 0.236, 0.109-0.362, P < 0.001) were both positively associated with cognitive decline. Multivariate logistic regression analyses demonstrated that patients with sarcopenia and non-sarcopenia to sarcopenia were both at increased risk of developing MCI [odds ratio (OR) 1.788, 95% CI 1.115-2.870, P = 0.016 and OR 1.589, 95% CI 1.087-2.324, P = 0.017, respectively], but only non-sarcopenia to sarcopenia was at increased risk of dementia (OR 1.792, 95% CI 1.108-2.879, P = 0.017). Both greater change of ASMI and HGS had lower risk of MCI with adjusted ORs of 0.857 (0.778-0.945, P = 0.002) and 0.976 (0.963-0.989, P < 0.001). Robust associations were found among female individuals, aged >60 years, and with low educational level. CONCLUSIONS: Longitudinal associations were observed between new-onset, persistent sarcopenia, and cognitive impairment. Early detection and intervention should be implemented to delay the onset of sarcopenia and improve cognitive health among HD patients.

17.
ACS Appl Mater Interfaces ; 15(29): 34436-34450, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37415554

RESUMO

Tumors have become the biggest obstacle to human health, and there are various treatment methods at present. Photothermal therapy (PTT) is usually ineffective and does not inhibit tumor progression due to the inability of the lasers to penetrate deeply. Therefore, most existing studies chose a 1064 nm laser with stronger penetrating power; meanwhile, studies have shown that the inclusion of harmful free radicals can significantly improve the antitumor efficacy. Herein, TiO nanosheets (NSs) were creatively prepared and encapsulated with an alkyl radical generator {2,2'-azobis[2-(2-imidazoline-2-yl)propane] dihydrochloride, [AIPH]} in sodium alginate (ALG) hydrogel for effective tumor killing by PTT and pairing with dangerous free radicals. TiO NSs were obtained by the liquid-phase exfoliation method, together with AIPH, which were in situ coencapsulated multifunctional hydrogels formed by the combination of Ca2+ and ALG. This ALG hydrogel could enrich TiO NSs and AIPH at the tumor site for a long time, and through the excellent photothermal properties of TiO NSs, AIPH could slowly and effectively generate alkyl radicals at the tumor site, which, in turn, gave it a better antitumor effect compared with that of TiO NSs in the deep hypoxic environment of the tumor. The AIPH + TiO + ALG hydrogel has distinctive anticancer capabilities based on the results of both in vivo and in vitro experiments. This material also has good biosafety. By combining PTT and free radical treatment, this work provides a novel therapeutic method to achieve oxygen-independent free radical production and enhance therapeutic efficacy.


Assuntos
Hidrogéis , Neoplasias , Humanos , Hidrogéis/química , Terapia Fototérmica , Fototerapia , Neoplasias/tratamento farmacológico , Termodinâmica , Radicais Livres/uso terapêutico , Linhagem Celular Tumoral
18.
Ren Fail ; 45(1): 2231084, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37427770

RESUMO

BACKGROUND: The optimal serum magnesium level of patients undergoing hemodialysis (HD) with cognitive impairment is still unclear. This study aimed to evaluate the association between serum magnesium levels and mild cognitive impairment among HD patients. METHODS: This was a multicenter observational study. Patients undergoing hemodialysis from 22 dialysis centers in Guizhou Province, China were recruited into the study. HD patients were divided into five groups according to serum magnesium quintile. Cognitive function was measured with Mini Mental State Examination. The outcome was an incident mild cognitive impairment (MCI). Multivariate logistic regression analysis, restricted cubic spline and subgroup analysis were applied to explore the association of serum magnesium level with MCI. RESULTS: Among 3562 HD patients (mean age 54.3 years, 60.1% male), the prevalence of MCI was 27.2%. After adjusting for confounders, serum magnesium 0.41-0.83 mmol/L [odds ratios (OR) 1.55, 95% confidence interval (CI): 1.10-2.18] had a higher risk of MCI compared with serum magnesium of 1.19-1.45 mmol/L. A U-shaped association was identified between the serum magnesium and incident MCI (P for non-linearity = 0.004). The optimal range of magnesium level with the lowest risk of MCI was 1.12-1.24 mmol/L. As the serum magnesium level was lower than 1.12 mmol/L, the risk of MCI decreased by 24% per standard deviation (SD) increase in serum magnesium (OR 0.76, 95%CI: 0.62-0.93); when the serum magnesium level exceeds 1.24 mmol/L, a rise per SD increased the risk of MCI by 21% (OR = 1.20, 95%CI: 1.02-1.43). Subgroup analyses demonstrated that the associations were robust among individuals with low educational level, smoking, living alone, no working, and without hypertension or diabetes. CONCLUSIONS: Serum magnesium has a U-shaped association with MCI among HD patients. Both lower and higher serum magnesium can increase the risk of MCI for this population specifically. The optimal serum magnesium range with the lowest risk of MCI was 1.12-1.24 mmol/L.


Assuntos
Disfunção Cognitiva , Hipertensão , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Magnésio , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Diálise Renal/efeitos adversos , Hipertensão/complicações , China/epidemiologia
19.
Biomaterials ; 299: 122182, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37276795

RESUMO

Photodynamic therapy (PDT) is emerging as a powerful tool for cancer treatment due to its unique advantages in terms of noninvasive and spatiotemporal selectivity. However, the residue of photosensitizers (PSs), which usually lead to thorny post-treatment side effects after photodynamic therapy (PDT), is one of bottlenecks for clinical translation. Herein, PSs with multiple degradation modes are developed to solve this issue. Upon 660 nm laser excitation, PSs can produce different types of reactive oxygen species (ROS), in which 1O2 and O2·- could kill the cancer cells, while ·OH could oxide the PSs themselves for photodegradation. After PDT, the residual few number of PSs could be further oxidized by endogenous ROS for biodegradation, and the degradation products could be further excreted by urine. This process therefore solves the slow-metabolism issue of traditional PSs. Among them, SQSe demonstrates the highest killing efficiency with best degradation ability, as confirmed by both in vitro and in vivo results. The postoperative safety of SQSe is further verified by assessment on in vivo artificially induced post-operative side effects.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Óxidos/uso terapêutico , Neoplasias/tratamento farmacológico
20.
Adv Sci (Weinh) ; 10(24): e2302208, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37340606

RESUMO

The fast conversion of hydrogen peroxide (H2 O2 ) into reactive oxygen species (ROS) at tumor sites is a promising anticancer strategy by manipulating nanomedicines with near-infrared light in the second region (NIR-II). However, this strategy is greatly compromised by the powerful antioxidant capacity of tumors and the limited ROS generation rate of nanomedicines. This dilemma mainly stems from the lack of an effective synthesis method to support high-density copper-based nanocatalysts on the surface of photothermal nanomaterials. Herein, a multifunctional nanoplatform (MCPQZ) with high-density cuprous (Cu2 O) supported molybdenum disulfide (MoS2 ) nanoflowers (MC NFs) is developed for the efficient killing of tumors via a potent ROS storm by an innovative method. Under NIR-II light irradiation, the ROS intensity and maximum reaction velocity (Vmax ) produced by MC NFs are 21.6 and 33.8 times that of the non-irradiation group in vitro, which is much higher than most current nanomedicines. Moreover, the strong ROS storm in cancer cells is efficiently formed by MCPQZ (increased by 27.8 times compared to the control), thanks to the fact that MCPQZ effectively pre-weakens the multiple antioxidant systems of cancer cells. This work provides a novel insight to solve the bottleneck of ROS-based cancer therapy.


Assuntos
Cobre , Molibdênio , Espécies Reativas de Oxigênio , Fototerapia/métodos , Antioxidantes , Linhagem Celular Tumoral
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