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1.
Proc Natl Acad Sci U S A ; 121(34): e2315759121, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39145935

ABSTRACT

Ubiquitination status of proliferating cell nuclear antigen (PCNA) is crucial for regulating DNA lesion bypass. After the resolution of fork stalling, PCNA is subsequently deubiquitinated, but the underlying mechanism remains undefined. We found that the N-terminal domain of ATAD5 (ATAD5-N), the largest subunit of the PCNA-unloading complex, functions as a scaffold for Ub-PCNA deubiquitination. ATAD5 recognizes DNA-loaded Ub-PCNA through distinct DNA-binding and PCNA-binding motifs. Furthermore, ATAD5 forms a heterotrimeric complex with UAF1-USP1 deubiquitinase, facilitating the deubiquitination of DNA-loaded Ub-PCNA. ATAD5 also enhances the Ub-PCNA deubiquitination by USP7 and USP11 through specific interactions. ATAD5 promotes the distinct deubiquitination process of UAF1-USP1, USP7, and USP11 for poly-Ub-PCNA. Additionally, ATAD5 mutants deficient in UAF1-binding had increased sensitivity to DNA-damaging agents. Our results ultimately reveal that ATAD5 and USPs cooperate to efficiently deubiquitinate Ub-PCNA prior to its release from the DNA in order to safely deactivate the DNA repair process.


Subject(s)
ATPases Associated with Diverse Cellular Activities , DNA-Binding Proteins , Proliferating Cell Nuclear Antigen , Ubiquitin Thiolesterase , Ubiquitin-Specific Peptidase 7 , Ubiquitination , ATPases Associated with Diverse Cellular Activities/metabolism , ATPases Associated with Diverse Cellular Activities/genetics , Proliferating Cell Nuclear Antigen/metabolism , Proliferating Cell Nuclear Antigen/genetics , Humans , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Ubiquitin Thiolesterase/metabolism , Ubiquitin Thiolesterase/genetics , Ubiquitin-Specific Peptidase 7/metabolism , Ubiquitin-Specific Peptidase 7/genetics , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Thiolester Hydrolases/metabolism , Thiolester Hydrolases/genetics , Ubiquitin/metabolism , DNA Damage , Protein Binding , Ubiquitin-Specific Proteases
2.
Am Heart J ; 271: 48-54, 2024 05.
Article in English | MEDLINE | ID: mdl-38401647

ABSTRACT

BACKGROUND: Both anticoagulation and antiplatelet therapies are recommended after percutaneous coronary intervention (PCI) in patients with atrial fibrillation (AF). Although contemporary guidelines recommend discontinuation of antiplatelet therapy 1 year after drug-eluting stent (DES) implantation due to excessive bleeding risk, supporting randomized trials are still lacking. METHODS: The ADAPT AF-DES trial is a multicenter, prospective, open-label, randomized, non-inferiority trial, enrolling 960 patients with AF with a CHA2DS2-VASc score > 1, who underwent PCI with DES implantation at least 12 months before enrollment. Eligible patients are randomly assigned to receive either non-vitamin K antagonist oral anticoagulant (NOAC) monotherapy or NOAC plus clopidogrel combination therapy. The primary outcome is net adverse clinical event (NACE) at 1 year after randomization, defined as a composite of all-cause death, myocardial infarction, stent thrombosis, stroke, systemic embolism, and major or clinically relevant non-major bleeding, as defined by the International Society on Thrombosis and Hemostasis criteria. We hypothesize that NOAC monotherapy would be non-inferior to NOAC plus clopidogrel combination therapy for NACE in patients with AF beyond 12 months after DES implantation. CONCLUSIONS: The ADAPT AF-DES trial will evaluate the efficacy and safety of NOAC monotherapy versus NOAC plus clopidogrel combination therapy in patients with AF beyond 12 months after PCI with DES implantation. The ADAPT AF-DES trial will provide robust evidence for an optimal antithrombotic strategy in patients with AF after DES implantation. CLINICAL TRIAL REGISTRATION: https://www. CLINICALTRIALS: gov. Unique identifier: NCT04250116.


Subject(s)
Anticoagulants , Atrial Fibrillation , Clopidogrel , Drug-Eluting Stents , Percutaneous Coronary Intervention , Platelet Aggregation Inhibitors , Female , Humans , Male , Anticoagulants/administration & dosage , Anticoagulants/therapeutic use , Atrial Fibrillation/complications , Atrial Fibrillation/drug therapy , Atrial Fibrillation/therapy , Clopidogrel/administration & dosage , Clopidogrel/therapeutic use , Drug Therapy, Combination , Hemorrhage/chemically induced , Percutaneous Coronary Intervention/methods , Platelet Aggregation Inhibitors/therapeutic use , Platelet Aggregation Inhibitors/administration & dosage , Prospective Studies , Stroke/prevention & control , Stroke/etiology , Time Factors , Randomized Controlled Trials as Topic , Multicenter Studies as Topic
3.
BJOG ; 131(9): 1306-1317, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38465460

ABSTRACT

OBJECTIVE: To evaluate the association between menopausal hormonal therapy (MHT) and the risk of cardiovascular disease (CVD), according to various regimens, dosages, routes of administration and starting ages of MHT. DESIGN: A population-based cohort study using the Korean National Health Insurance Services database. SETTING: Nationwide health insurance database. POPULATION: Women who reported entering menopause at an age of ≥40 years with no history of CVD in the national health examination. METHODS: The study population comprised 1 120 705 subjects enrolled between 2002 and 2019, categorised according to MHT status (MHT group, n = 319 007; non-MHT group, n = 801 698). MAIN OUTCOME MEASURES: Incidence of CVD (a composite of myocardial infarction and stroke). RESULTS: The incidence of CVD was 59 266 (7.4%) in the non-MHT group and 17 674 (5.5%) in the MHT group. After adjusting for confounding factors, an increased risk of CVD was observed with the administration of tibolone (hazard ratio, HR 1.143, 95% CI 1.117-1.170), oral estrogen (HR 1.246, 95% CI 1.198-1.295) or transdermal estrogen (HR 1.289, 95% CI 1.066-1.558), compared with the non-MHT group; the risk was based on an increased risk of stroke. The risk trends were consistent regardless of the age of starting MHT or the physicians' specialty. Among tibolone users, a longer period from entering menopause to taking tibolone and the use of any dosage (1.25 or 2.5 mg) were linked with a higher risk of CVD, compared with non-MHT users. CONCLUSIONS: This nationwide cohort study demonstrated an increased risk of CVD, driven mainly by an increased risk of stroke, among tibolone and oral or transdermal estrogen users, compared with that of non-MHT users.


Subject(s)
Cardiovascular Diseases , Estrogen Replacement Therapy , Norpregnenes , Postmenopause , Humans , Female , Middle Aged , Republic of Korea/epidemiology , Cardiovascular Diseases/epidemiology , Estrogen Replacement Therapy/adverse effects , Estrogen Replacement Therapy/statistics & numerical data , Norpregnenes/adverse effects , Cohort Studies , Incidence , Adult , Aged , Estrogens/adverse effects , Estrogens/administration & dosage , Stroke/epidemiology , Stroke/chemically induced , Risk Factors , Heart Disease Risk Factors , Databases, Factual
4.
Heliyon ; 10(12): e32931, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39021898

ABSTRACT

Recently, with the remarkable development of deep learning technology, achievements are being updated in various computer vision fields. In particular, the object recognition field is receiving the most attention. Nevertheless, recognition performance for small objects is still challenging. Its performance is of utmost importance in realistic applications such as searching for missing persons through aerial photography. The core structure of the object recognition neural network is the feature pyramid network (FPN). You Only Look Once (YOLO) is the most widely used representative model following this structure. In this study, we proposed an attention-based scale sequence network (ASSN) that improves the scale sequence feature pyramid network (ssFPN), enhancing the performance of the FPN-based detector for small objects. ASSN is a lightweight attention module optimized for FPN-based detectors and has the versatility to be applied to any model with a corresponding structure. The proposed ASSN demonstrated performance improvements compared to the baselines (YOLOv7 and YOLOv8) in average precision (AP) of up to 0.6%. Additionally, the AP for small objects ( A P S ) showed also improvements of up to 1.9%. Furthermore, ASSN exhibits higher performance than ssFPN while achieving lightweightness and optimization, thereby improving computational complexity and processing speed. ASSN is open-source based on YOLO version 7 and 8. This can be found in our public repository: https://github.com/smu-ivpl/ASSN.git.

5.
Cancer Res Commun ; 4(6): 1517-1532, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38747592

ABSTRACT

Proteasomes degrade intracellular proteins to generate antigenic peptides that are recognized by the adaptive immune system and promote anticancer immunity. However, tumors subvert the antigen presentation machinery to escape immunosurveillance. We hypothesized that proteasome activation could concomitantly increase antigen abundance and diversity in multiple myeloma cells. High-throughput screens revealed that histone deacetylase 6 (HDAC6) inhibitors activated proteasomes to unmask neoantigens and amplify the tumor-specific antigenic landscape. Treatment of patient CD138+ cells with HDAC6 inhibitors significantly promoted the antimyeloma activity of autologous CD8+ T cells. Pharmacologic blockade and genetic ablation of the HDAC6 ubiquitin-binding domain released HR23B, which shuttles ubiquitinylated cargo to proteasomes, while silencing HDAC6 or HR23B in multiple myeloma cells abolished the effect of HDAC6 inhibitors on proteasomes, antigen presentation, and T-cell cytotoxicity. Taken together, our results demonstrate the paradigm-shifting translational impact of proteasome activators to expand the myeloma immunopeptidome and have revealed novel, actionable antigenic targets for T cell-directed immunotherapy. SIGNIFICANCE: The elimination of therapy-resistant tumor cells remains a major challenge in the treatment of multiple myeloma. Our study identifies and functionally validates agents that amplify MHC class I-presented antigens and pave the way for the development of proteasome activators as immune adjuvants to enhance immunotherapeutic responses in patients with multiple myeloma.


Subject(s)
Histone Deacetylase 6 , Histone Deacetylase Inhibitors , Multiple Myeloma , Proteasome Endopeptidase Complex , Humans , Histone Deacetylase 6/antagonists & inhibitors , Histone Deacetylase 6/metabolism , Proteasome Endopeptidase Complex/metabolism , Proteasome Endopeptidase Complex/immunology , Proteasome Endopeptidase Complex/drug effects , Multiple Myeloma/immunology , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Histone Deacetylase Inhibitors/pharmacology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Antigen Presentation/drug effects , Antigens, Neoplasm/immunology , Antigens, Neoplasm/metabolism
6.
Oncoimmunology ; 12(1): 2281179, 2023.
Article in English | MEDLINE | ID: mdl-38126029

ABSTRACT

Functional effector T cells in the tumor microenvironment (TME) are critical for successful anti-tumor responses. T cell anti-tumor function is dependent on their ability to differentiate from a naïve state, infiltrate into the tumor site, and exert cytotoxic functions. The factors dictating whether a particular T cell can successfully undergo these processes during tumor challenge are not yet completely understood. Piezo1 is a mechanosensitive cation channel with high expression on both CD4+ and CD8+ T cells. Previous studies have demonstrated that Piezo1 optimizes T cell activation and restrains the CD4+ regulatory T cell (Treg) pool in vitro and under inflammatory conditions in vivo. However, little is known about the role Piezo1 plays on CD4+ and CD8+ T cells in cancer. We hypothesized that disruption of Piezo1 on T cells impairs anti-tumor immunity in vivo by hindering inflammatory T cell responses. We challenged mice with T cell Piezo1 deletion (P1KO) with tumor models dependent on T cells for immune rejection. P1KO mice had the more aggressive tumors, higher tumor growth rates and were unresponsive to immune-mediated therapeutic interventions. We observed a decreased CD4:CD8 ratio in both the secondary lymphoid organs and TME of P1KO mice that correlated inversely with tumor size. Poor CD4+ helper T cell responses underpinned the immunodeficient phenotype of P1KO mice. Wild type CD8+ T cells are sub-optimally activated in vivo with P1KO CD4+ T cells, taking on a CD25loPD-1hi phenotype. Together, our results suggest that Piezo1 optimizes T cell activation in the context of a tumor response.


Subject(s)
Antineoplastic Agents , Neoplasms , Animals , Mice , CD8-Positive T-Lymphocytes , T-Lymphocytes, Regulatory/metabolism , Tumor Microenvironment , Ion Channels/genetics , Ion Channels/metabolism
8.
Arq. bras. cardiol ; 106(1): 56-61, Jan. 2016. tab
Article in Portuguese | LILACS | ID: lil-771052

ABSTRACT

Abstract Background: Hemorheological and glycemic parameters and high density lipoprotein (HDL) cholesterol are used as biomarkers of atherosclerosis and thrombosis. Objective: To investigate the association and clinical relevance of erythrocyte sedimentation rate (ESR), fibrinogen, fasting glucose, glycated hemoglobin (HbA1c), and HDL cholesterol in the prediction of major adverse cardiovascular events (MACE) and coronary heart disease (CHD) in an outpatient population. Methods: 708 stable patients who visited the outpatient department were enrolled and followed for a mean period of 28.5 months. Patients were divided into two groups, patients without MACE and patients with MACE, which included cardiac death, acute myocardial infarction, newly diagnosed CHD, and cerebral vascular accident. We compared hemorheological and glycemic parameters and lipid profiles between the groups. Results: Patients with MACE had significantly higher ESR, fibrinogen, fasting glucose, and HbA1c, while lower HDL cholesterol compared with patients without MACE. High ESR and fibrinogen and low HDL cholesterol significantly increased the risk of MACE in multivariate regression analysis. In patients with MACE, high fibrinogen and HbA1c levels increased the risk of multivessel CHD. Furthermore, ESR and fibrinogen were significantly positively correlated with HbA1c and negatively correlated with HDL cholesterol, however not correlated with fasting glucose. Conclusion: Hemorheological abnormalities, poor glycemic control, and low HDL cholesterol are correlated with each other and could serve as simple and useful surrogate markers and predictors for MACE and CHD in outpatients.


Resumo Fundamento: Parâmetros hemorreológicos e glicêmicos e o HDL-colesterol são utilizados como biomarcadores da aterosclerose e trombose. Objetivo: Investigar a associação e a relevância clínica da velocidade de hemossedimentação (VHS), fibrinogênio, glicose de jejum, hemoglobina glicada (HbA1c) e HDL-colesterol na predição de eventos adversos cardiovasculares (EAC) importantes em pacientes ambulatoriais. Métodos: 708 pacientes estáveis ambulatoriais foram incluídos no estudo e acompanhados por um período médio de 28,5 meses. Os pacientes foram subdivididos em pacientes sem EAC e pacientes com EAC, que incluíram morte súbita cardíaca, infarto agudo do miocárdio, doença coronariana recém-diagnosticada, e acidente vascular cerebral. Comparamos os parâmetros hemorreológicos, glicêmicos, e perfis lipídicos entre os grupos. Resultados: Pacientes com EAC apresentaram níveis significativamente mais elevados de VHS, fibrinogênio, glicose de jejum, e HbA1c, e níveis mais baixos de HDL-colesterol em comparação a pacientes sem EAC. VHS e níveis de fibrinogênio elevados, e baixos níveis de HDL-colesterol aumentaram significativamente o risco de EAC em análise de regressão multivariada. Além disso, VHS e fibrinogênio correlacionaram-se positivamente com HbA1c e negativamente com HDL-colesterol, mas não se correlacionaram com glicose de jejum. Conclusão: Distúrbios hemorreológicos, baixo controle glicêmico e baixo nível de HDL-colesterol correlacionam-se entre si e podem ser usados como marcadores substitutos simples, úteis, e como preditores de EAC e doença coronariana em pacientes ambulatoriais.


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Blood Glucose/analysis , Cardiovascular Diseases/blood , Cholesterol, HDL/blood , Coronary Disease/blood , Fibrinogen/analysis , Glycated Hemoglobin/analysis , Blood Sedimentation , Biomarkers/blood , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/etiology , Coronary Disease/diagnosis , Coronary Disease/etiology , Glycemic Index , Hemorheology , Outpatients , Predictive Value of Tests , Reproducibility of Results , Risk Factors , Statistics, Nonparametric
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