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1.
Proc Natl Acad Sci U S A ; 120(11): e2219170120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36888657

RESUMO

The enrichment of histone H3 variant CENP-A is the epigenetic mark of centromere and initiates the assembly of the kinetochore at centromere. The kinetochore is a multi-subunit complex that ensures accurate attachment of microtubule centromere and faithful segregation of sister chromatids during mitosis. As a subunit of kinetochore, CENP-I localization at centromere also depends on CENP-A. However, whether and how CENP-I regulates CENP-A deposition and centromere identity remains unclear. Here, we identified that CENP-I directly interacts with the centromeric DNA and preferentially recognizes AT-rich elements of DNA via a consecutive DNA-binding surface formed by conserved charged residues at the end of N-terminal HEAT repeats. The DNA binding-deficient mutants of CENP-I retained the interaction with CENP-H/K and CENP-M, but significantly diminished the centromeric localization of CENP-I and chromosome alignment in mitosis. Moreover, the DNA binding of CENP-I is required for the centromeric loading of newly synthesized CENP-A. CENP-I stabilizes CENP-A nucleosomes upon binding to nucleosomal DNA instead of histones. These findings unveiled the molecular mechanism of how CENP-I promotes and stabilizes CENP-A deposition and would be insightful for understanding the dynamic interplay of centromere and kinetochore during cell cycle.


Assuntos
Centrômero , Proteínas Cromossômicas não Histona , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Centrômero/genética , Centrômero/metabolismo , Histonas/genética , Histonas/metabolismo , Nucleossomos/genética , DNA/genética , Mitose , Autoantígenos/metabolismo
2.
Circ Res ; 133(3): 237-251, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37345556

RESUMO

BACKGROUND: Progressive cardiac fibrosis leads to ventricular wall stiffness, cardiac dysfunction, and eventually heart failure, but the underlying mechanism remains unexplored. PDCD5 (programmed cell death 5) ubiquitously expresses in tissues, including the heart; however, the role of PDCD5 in cardiac fibrosis is largely unknown. Therefore, this study aims at exploring the possible role and underlying mechanisms of PDCD5 in the pathogenesis of cardiac fibrosis. METHODS AND RESULTS: PDCD5 levels were found to be elevated in the serum obtained from patients with cardiac fibrosis, in fibrotic mice heart tissues after myocardial infarction, and in cardiac fibroblasts stimulated by Ang II (angiotensin II)- or TGF-ß1 (transforming growth factor-ß1). Overexpression of PDCD5 in cardiac fibroblasts or treatment with PDCD5 protein reduced the expression of profibrogenic proteins in response to TGF-ß1 stimulation, while knockdown of PDCD5 increased fibrotic responses. It has been demonstrated that SMAD3, a protein that is also known as mothers against decapentaplegic homolog 3, directly upregulated PDCD5 during cardiac fibrosis. Subsequently, the increased PDCD5 promoted HDAC3 (histone deacetylase 3) ubiquitination, thus, inhibiting HDAC3 to reduce fibrotic responses. Fibroblast-specific knock-in of PDCD5 in mice ameliorated cardiac fibrosis after myocardial infarction and enhanced cardiac function, and these protective effects were eliminated by AAV9-mediated HDAC3 overexpression. CONCLUSIONS: The findings of this study demonstrated that PDCD5 is upregulated by SMAD3 during cardiac fibrosis, which subsequently ameliorated progressive fibrosis and cardiac dysfunction through HDAC3 inhibition. Thus, this study suggests that PDCD5 functions as a negative feedback factor on fibrotic signaling pathways and might serve as a potential therapeutic target to suppress the progression of fibrotic responses.


Assuntos
Infarto do Miocárdio , Fator de Crescimento Transformador beta1 , Camundongos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Infarto do Miocárdio/metabolismo , Coração , Fibroblastos/metabolismo , Apoptose , Fibrose , Proteína Smad3/metabolismo , Miocárdio/metabolismo
3.
J Biol Chem ; 299(1): 102787, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36509141

RESUMO

Chemoresistance remains a major challenge in the current treatment of acute myeloid leukemia (AML). The bone marrow microenvironment (BMM) plays a complex role in protecting leukemia cells from chemotherapeutics, and the mechanisms involved are not fully understood. Antileukemia drugs kill AML cells directly but also damage the BMM. Here, we determined antileukemia drugs induce DNA damage in bone marrow stromal cells (BMSCs), resulting in resistance of AML cell lines to adriamycin and idarubicin killing. Damaged BMSCs induced an inflammatory microenvironment through NF-κB; suppressing NF-κB with small molecule inhibitor Bay11-7082 attenuated the prosurvival effects of BMSCs on AML cell lines. Furthermore, we used an ex vivo functional screen of 507 chemokines and cytokines to identify 44 proteins secreted from damaged BMSCs. Fibroblast growth factor-10 (FGF10) was most strongly associated with chemoresistance in AML cell lines. Additionally, expression of FGF10 and its receptors, FGFR1 and FGFR2, was increased in AML patients after chemotherapy. FGFR1 and FGFR2 were also widely expressed by AML cell lines. FGF10-induced FGFR2 activation in AML cell lines operates by increasing P38 MAPK, AKT, ERK1/2, and STAT3 phosphorylation. FGFR2 inhibition with small molecules or gene silencing of FGFR2 inhibited proliferation and reverses drug resistance of AML cells by inhibiting P38 MAPK, AKT, and ERK1/2 signaling pathways. Finally, release of FGF10 was mediated by ß-catenin signaling in damaged BMSCs. Our data indicate FGF10-FGFR2 signaling acts as an effector of damaged BMSC-mediated chemoresistance in AML cells, and FGFR2 inhibition can reverse stromal protection and AML cell chemoresistance in the BMM.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Humanos , Células da Medula Óssea/metabolismo , Dano ao DNA , Fator 10 de Crescimento de Fibroblastos/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Mesenquimais/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Células Estromais/metabolismo , Microambiente Tumoral , Comunicação Parácrina
4.
Anal Chem ; 96(26): 10677-10685, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38889311

RESUMO

Exploring the ability of four-stranded DNA nanorings (fsDNRs) to host multiple nanosilver clusters (NAgCs) for cooperatively amplifiable fluorescence biosensing to a specific initiator (tI*) is fascinating. By designing three DNA single strands and three analogous stem-loop hairpins, we developed a functional fsDNR through sequential cross-opening and overlapped hybridization. Note that a substrate strand (SS) was programmed with six modules: two severed splits (sT and sT') of NAgCs template, two sequestered segments by a middle unpaired spacer, and a partition for tI*-recognizable displacement, while sT and sT' were also tethered in two ends of three hairpins. At first, a triple dsDNA complex with stimulus-responsiveness was formed to guide the specific binding to tI*, while the exposed toehold of the SS activated the forward cascade hybridization of three hairpins, until the ring closure in the tailored self-assembly pathway for forming the fsDNR. The resulting four duplexes forced each pair of sT/sT' to be merged as the parent template in four nicks, guiding the preferential synthesis of four clusters in the shared fsDNR, thereby cooperatively amplifying the green fluorescence signal for sensitive assay of tI*. Meanwhile, the topological conformation of fsDNR can be stabilized by the as-formed cluster adducts to rivet the pair of two splits in the nicks. Benefitting from the self-enhanced effect of multiple emitters, this label-free fluorescent sensing strategy features simplicity, rapidity, and high on-off contrast, without involving complicated nucleic acid amplifiers.


Assuntos
Técnicas Biossensoriais , DNA , Técnicas Biossensoriais/métodos , DNA/química , Prata/química , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Fluorescência , Espectrometria de Fluorescência , Nanotubos/química
5.
J Pineal Res ; 76(5): e12991, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39039850

RESUMO

Although rapid progression and a poor prognosis in influenza A virus (IAV) infection-induced acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are frequently associated with metabolic energy disorders, the underlying mechanisms and rescue strategies remain unknown. We herein demonstrated that the level of resting energy expenditure increased significantly in IAV-induced AECOPD patients and that cellular energy exhaustion emerged earlier and more significantly in IAV-infected primary COPD bronchial epithelial (pDHBE) cells. The differentially expressed genes were enriched in the oxidative phosphorylation (OXPHOS) pathway; additionally, we consistently uncovered much earlier ATP exhaustion, more severe mitochondrial structural destruction and dysfunction, and OXPHOS impairment in IAV-inoculated pDHBE cells, and these changes were rescued by melatonin. The level of OMA1-dependent cleavage of OPA1 in the mitochondrial inner membrane and the shift in energy metabolism from OXPHOS to glycolysis were significantly increased in IAV-infected pDHBE cells; however, these changes were rescued by OMA1-siRNA or melatonin further treatment. Collectively, our data revealed that melatonin rescued IAV-induced cellular energy exhaustion via OMA1-OPA1-S to improve the clinical prognosis in COPD. This treatment may serve as a potential therapeutic agent for patients in which AECOPD is induced by IAV.


Assuntos
Metabolismo Energético , GTP Fosfo-Hidrolases , Vírus da Influenza A , Melatonina , Doença Pulmonar Obstrutiva Crônica , Humanos , Metabolismo Energético/efeitos dos fármacos , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Vírus da Influenza A/efeitos dos fármacos , Influenza Humana/metabolismo , Influenza Humana/tratamento farmacológico , Melatonina/farmacologia , Metaloendopeptidases , Fosforilação Oxidativa/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
6.
Future Oncol ; 20(28): 2071-2081, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39041580

RESUMO

Aim: This multicenter retrospective study aimed to develop a novel prognostic system for extranodal natural killer/T-cell lymphoma (ENKTL) patients in the era of pegaspargase/L-asparaginase.Materials & methods: A total of 844 newly diagnosed ENKTL patients were included.Results: Multivariable analysis confirmed that Eastern Cooperative Oncology Group performance status, lactate dehydrogenase, Chinese Southwest Oncology Group and Asia Lymphoma Study Group ENKTL (CA) system, and albumin were independent prognostic factors. By rounding up the hazard ratios from four significant variables, a maximum of 7 points were assigned. The model of Huaihai Lymphoma Working Group-Natural killer/T-cell Lymphoma prognostic index (NPI) was identified with four risk groups and the 5-year overall survival was 88.2, 66.7, 54.3 and 30.5%, respectively.Conclusion: Huaihai Lymphoma Working Group-NPI provides a feasible stratification system for patients with ENKTL in the era of pegaspargase/L-asparaginase.


[Box: see text].


Assuntos
Asparaginase , Linfoma Extranodal de Células T-NK , Polietilenoglicóis , Humanos , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Linfoma Extranodal de Células T-NK/mortalidade , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/patologia , Asparaginase/uso terapêutico , Feminino , Polietilenoglicóis/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto , Estudos Retrospectivos , Adolescente , Idoso , Adulto Jovem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança
7.
J Nanobiotechnology ; 22(1): 198, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649957

RESUMO

Heat shock protein 90 (HSP90) is overexpressed in numerous cancers, promotes the maturation of numerous oncoproteins and facilitates cancer cell growth. Certain HSP90 inhibitors have entered clinical trials. Although less than satisfactory clinical effects or insurmountable toxicity have compelled these trials to be terminated or postponed, these results of preclinical and clinical studies demonstrated that the prospects of targeting therapeutic strategies involving HSP90 inhibitors deserve enough attention. Nanoparticulate-based drug delivery systems have been generally supposed as one of the most promising formulations especially for targeting strategies. However, so far, no active targeting nano-formulations have succeeded in clinical translation, mainly due to complicated preparation, complex formulations leading to difficult industrialization, incomplete biocompatibility or nontoxicity. In this study, HSP90 and CD44-targeted A6 peptide functionalized biomimetic nanoparticles (A6-NP) was designed and various degrees of A6-modification on nanoparticles were fabricated to evaluate targeting ability and anticancer efficiency. With no excipients, the hydrophobic HSP90 inhibitor G2111 and A6-conjugated human serum albumin could self-assemble into nanoparticles with a uniform particle size of approximately 200 nm, easy fabrication, well biocompatibility and avoidance of hepatotoxicity. Besides, G2111 encapsulated in A6-NP was only released less than 5% in 12 h, which may avoid off-target cell toxicity before entering into cancer cells. A6 peptide modification could significantly enhance uptake within a short time. Moreover, A6-NP continues to exert the broad anticancer spectrum of Hsp90 inhibitors and displays remarkable targeting ability and anticancer efficacy both in hematological malignancies and solid tumors (with colon tumors as the model cancer) both in vitro and in vivo. Overall, A6-NP, as a simple, biomimetic and active dual-targeting (CD44 and HSP90) nanomedicine, displays high potential for clinical translation.


Assuntos
Antineoplásicos , Neoplasias do Colo , Proteínas de Choque Térmico HSP90 , Receptores de Hialuronatos , Leucemia Mieloide Aguda , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Animais , Linhagem Celular Tumoral , Camundongos , Neoplasias do Colo/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/química , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Camundongos Nus , Camundongos Endogâmicos BALB C , Peptídeos/química , Peptídeos/farmacologia
8.
J Biopharm Stat ; : 1-23, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363805

RESUMO

There has been an increasing use of master protocols in oncology clinical trials because of its efficiency to accelerate cancer drug development and flexibility to accommodate multiple substudies. Depending on the study objective and design, a master protocol trial can be a basket trial, an umbrella trial, a platform trial, or any other form of trials in which multiple investigational products and/or subpopulations are studied under a single protocol. Master protocols can use external data and evidence (e.g. external controls) for treatment effect estimation, which can further improve efficiency of master protocol trials. This paper provides an overview of different types of external controls and their unique features when used in master protocols. Some key considerations in master protocols with external controls are discussed including construction of estimands, assessment of fit-for-use real-world data, and considerations for different types of master protocols. Similarities and differences between regular randomized controlled trials and master protocols when using external controls are discussed. A targeted learning-based causal roadmap is presented which constitutes three key steps: (1) define a target statistical estimand that aligns with the causal estimand for the study objective, (2) use an efficient estimator to estimate the target statistical estimand and its uncertainty, and (3) evaluate the impact of causal assumptions on the study conclusion by performing sensitivity analyses. Two illustrative examples for master protocols using external controls are discussed for their merits and possible improvement in causal effect estimation.

9.
Mar Drugs ; 22(8)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39195448

RESUMO

Co-cultivation is a powerful emerging tool for awakening biosynthetic gene clusters (BGCs) that remain transcriptionally silent under artificial culture conditions. It has recently been used increasingly extensively to study natural interactions and discover new bioactive metabolites. As a part of our project aiming at the discovery of structurally novel and biologically active natural products from mangrove endophytic fungi, an established co-culture of a strain of Phomopsis asparagi DHS-48 with another Phomopsis genus fungus DHS-11, both endophytes in mangrove Rhizophora mangle, proved to be very efficient to induce the production of new metabolites as well as to increase the yields of respective target metabolites. A detailed chemical investigation of the minor metabolites produced by the co-culture of these two titled fungal strains led to the isolation of six alkaloids (1-6), two sterols (7, 8), and six polyketides (9-14). In addition, all the compounds except 8 and 10, as well as three new metabolites phomopyrazine (1), phomosterol C (7), and phomopyrone E (9), were not present in discrete fungal cultures and only detected in the co-cultures. The structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations were assumed by electronic circular dichroism (ECD) calculations. Subsequently, the cytotoxic, immunosuppressive, and acetylcholinesterase inhibitory properties of all the isolated metabolites were determined in vitro. Compound 8 exhibited moderate inhibitory activity against ConA-induced T and LPS-induced B murine splenic lymphocytes, with IC50 values of 35.75 ± 1.09 and 47.65 ± 1.21 µM, respectively.


Assuntos
Técnicas de Cocultura , Endófitos , Phomopsis , Rhizophoraceae , Animais , Camundongos , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/isolamento & purificação , Endófitos/metabolismo , Phomopsis/metabolismo , Policetídeos/metabolismo , Policetídeos/farmacologia , Policetídeos/isolamento & purificação , Policetídeos/química , Rhizophoraceae/microbiologia , Metabolismo Secundário
10.
Zhongguo Zhong Yao Za Zhi ; 49(2): 559-564, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403330

RESUMO

This study aims to summarize the research hotspots and trends in traditional Chinese medicine(TCM) treatment of trauma and provide suggestions for collaborative research on the treatment of trauma with integrated Chinese and western medicine. The re-levant research articles on TCM treatment of trauma were searched against CNKI, Wanfang, VIP, Web of Science, and PubMed from inception to December 31, 2022 and analyzed using bibliometric. After screening, 315 articles in Chinese and 34 articles in English were included. The articles were mainly published by TCM journals. The core author groups were absent. The author affiliations were dominated by medical institutions and supplemented by universities, research institutions, and government agencies. The research mainly focused on the clinical practice and trials of TCM in trauma treatment. Although the TCM treatment of trauma emerged early, it is still in the initial stage of development. The future research can focus on innovating the service model of trauma treatment, improving clinical research capability, improving medical quality management, and strengthening the TCM talent teams in comprehensive hospitals. Western medicine is precise and effective in the treatment of trauma, while TCM with unique treatment methods and effects can play a complementary role. Therefore, the trauma treatment with integrated Chinese and western medicine demonstrates a promising prospect.


Assuntos
Medicina Tradicional Chinesa , Ferimentos e Lesões , Bibliometria , Ferimentos e Lesões/terapia
11.
Anal Chem ; 95(13): 5710-5718, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36941819

RESUMO

Exploring the cooperative amplification of peroxidase-like metal nanocomposites and cycled hairpin assembly is intriguing for sensitive bioanalysis. Herein, we report the first design of a unique electrochemical biosensor based on mimicking Au@FeCo nanozymes and bicycled hairpin assembly (BHA) for synergistic signal amplification. By loading the enzyme-like FeCo alloy in Au nanoparticles (AuNPs), the as-synthesized Au@FeCo hybrids display great improvement of electronic conductivity and active surface area and excellent mimic catalase activity to H2O2 decomposition into •OH radicals. The immobilization of Au@FeCo in an electrode sensing interface is stabilized via the resulting electrodeposition in HAuCl4 while efficiently accelerating the electron transfer of electroactive ferrocene (Fc). Upon the immobilization of a helping hairpin (HH) via Au-S bonds, a specific DNA trigger (T*) is introduced to activate BHA operation through competitive strand displacement reactions among recognizing hairpin (RH), signaling hairpin (SH), and HH. T* and RH are rationally released to catalyze two cycles, in which the transient depletion of dsDNA intermediates rapidly drives the progressive hairpin assemblies to output more products SH·HH. Thus, the efficient amplification of Au@FeCo mimic catalase activity combined with BHA leads to a significantly increased current signal of Fc dependent on miRNA-21 analogous to T*, thereby directing the creation of a highly sensitive electrochemical biosensor having applicable potential in actual samples.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro/química , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio , Catalase , Nanopartículas Metálicas/química , DNA/química , Técnicas Biossensoriais/métodos , Limite de Detecção
12.
Biochem Biophys Res Commun ; 667: 162-169, 2023 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-37229825

RESUMO

OBJECTIVES: Cardiac hypertrophy is the heart's compensatory response stimulated by various pathophysiological factors. However, prolonged cardiac hypertrophy poses a significant risk of progression to heart failure, lethal arrhythmias, and even sudden cardiac death. For this reason, it is crucial to effectively prevent the occurrence and development of cardiac hypertrophy. CMTM is a superfamily of human chemotaxis, which is involved in immune response and tumorigenesis. CMTM3 expressed widely in tissues, including the heart, but its cardiac function remains unclear. This research aims to explore the effect and mechanism of CMTM3 in the development of cardiac hypertrophy. METHODS AND RESULTS: We generated a Cmtm3 knockout mouse model (Cmtm3-/-) as the loss-of-function approach. CMTM3 deficiency induced cardiac hypertrophy and further exacerbated hypertrophy and cardiac dysfunction stimulated by Angiotensin Ⅱ infusion. In Ang Ⅱ-infusion stimulated hypertrophic hearts and phenylephrine-induced hypertrophic neonatal cardiomyocytes, CMTM3 expression significantly increased. However, adenovirus-mediated overexpression of CMTM3 inhibited the hypertrophy of rat neonatal cardiomyocytes induced by PE stimulation. In terms of mechanism, RNA-seq data revealed that Cmtm3 knockout-induced cardiac hypertrophy was related to MAPK/ERK activation. In vitro, CMTM3 overexpression significantly inhibited the increased phosphorylation of p38 and ERK induced by PE stimulation. CONCLUSIONS: CMTM3 deficiency induces cardiac hypertrophy and aggravates hypertrophy and impaired cardiac function stimulated by angiotensin Ⅱ infusion. The expression of CMTM3 increases during cardiac hypertrophy, and the increased CMTM3 can inhibit further hypertrophy of cardiomyocytes by inhibiting MAPK signaling. Thus, CMTM3 plays a negative regulatory effect in the occurrence and development of cardiac hypertrophy.


Assuntos
Cardiomegalia , Quimiocinas , Proteínas com Domínio MARVEL , Animais , Camundongos , Cardiomegalia/metabolismo , Proteínas com Domínio MARVEL/genética , Proteínas com Domínio MARVEL/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Técnicas de Inativação de Genes , Angiotensina II/metabolismo , Miócitos Cardíacos/metabolismo , Regulação para Cima , Fenilefrina , Ratos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Fosforilação , Coração
13.
Biochem Biophys Res Commun ; 659: 40-45, 2023 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-37031593

RESUMO

The O-carbamoyltransferase VtdB catalyzes the carbamoylation of venturicidin B, which is essential for the biosynthesis of the antibiotic venturicidin A. Here, the crystal structures of VtdB and VtdB in complex with the intermediate carbamoyladenylate (VtdBCAO) were determined at resolutions of 2.99 Å and 2.90 Å, respectively. The structures resemble the conserved YrdC-like and specific Kae1-like domains. A magnesium ion and the intermediate carbamoyladenylate were also observed in the Kae1-like domain of VtdB. The structure of VtdBCAO in complex with the substrate venturicidin B was modeled by a molecular docking method to better understand the substrate binding mode, revealing a novel venturicidin B binding pocket.


Assuntos
Streptomyces , Simulação de Acoplamento Molecular , Sítios de Ligação , Cristalografia por Raios X , Especificidade por Substrato
14.
Small ; 19(26): e2206438, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36960479

RESUMO

DNA origami molds allow a shape-controlled growth of metallic nanoparticles. So far, this approach is limited to gold and silver. Here, the fabrication of linear palladium nanostructures with controlled lengths and patterns is demonstrated. To obtain nucleation centers for a seeded growth, a synthesis procedure of palladium nanoparticles (PdNPs) using Bis(p-sulfonatophenyl)phenylphosphine (BSPP) both as reductant and stabilizer is developed to establish an efficient functionalization protocol of the particles with single-stranded DNA. Attaching the functionalized particles to complementary DNA strands inside DNA mold cavities supports subsequently a highly specific seeded palladium deposition. This provides rod-like PdNPs with diameters of 20-35 nm of grainy morphology. Using an annealing procedure and a post-reduction step with hydrogen, homogeneous palladium nanostructures can be obtained. With the adaptation of the procedure to palladium the capabilities of the mold-based tool-box are expanded. In the future, this may allow a facile adaptation of the mold approach to less noble metals including magnetic materials such as Ni and Co.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Paládio , Nanopartículas Metálicas/química , Nanoestruturas/química , DNA/química , Ouro/química
15.
Cancer Cell Int ; 23(1): 129, 2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37394466

RESUMO

BACKGROUND: The gefitinib resistance mechanism in non-small cell lung cancer (NSCLC) remains unclear, albeit exosomal circular RNA (circRNA) is known to possibly play a vital role in it. METHODS: We employed high-throughput sequencing techniques to detect the expressions of exosomal circRNA both in gefitinib-resistant and gefitinib-sensitive cells in this study. The circKIF20B expression was determined in serum exosomes and tissues of patients by qRT-PCR. The structure, stability, and intracellular localization of circKIF20B were verified by Sanger sequencing, Ribonuclease R (RNase R)/actinomycin D (ACTD) treatments, and Fluorescence in situ hybridization (FISH). The functions of circKIF20B were investigated by 5-Ethynyl-20-deoxyuridine (EdU), flow cytometry, Cell Counting Kit-8 (CCK-8), oxygen consumption rate (OCR), and xenograft model. Co-culture experiments were performed to explore the potential ability of exosomal circKIF20B in treating gefitinib resistance. The downstream targets of circKIF20B were determined by luciferase assay, RNA pulldown, and RNA immunoprecipitation (RIP). RESULTS: We found that circKIF20B was poorly expressed in the serum exosomes of gefitinib-resistant patients (n = 24) and the tumor tissues of patients with NSCLC (n = 85). CircKIF20B was negatively correlated with tumor size and tumor stage. Decreasing circKIF20B was found to promote gefitinib resistance by accelerating the cell cycle, inhibiting apoptosis, and enhancing mitochondrial oxidative phosphorylation (OXPHOS), whereas increasing circKIF20B was found to restore gefitinib sensitivity. Mechanistically, circKIF20B is bound to miR-615-3p for regulating the MEF2A and then altering the cell cycle, apoptosis, and mitochondrial OXPHOS. Overexpressing circKIF20B parental cells can restore sensitivity to gefitinib in the recipient cells by upregulating the exosomal circKIF20B expression. CONCLUSIONS: This study revealed a novel mechanism of circKIF20B/miR-615-3p/MEF2A signaling axis involving progression of gefitinib resistance in NSCLC. Exosomal circKIF20B is expected to be an easily accessible and alternative liquid biopsy candidate and potential therapeutic target in gefitinib-resistant NSCLC. The schematic diagram of mechanism in this study. Exosomal circKIF20B inhibits gefitinib resistance and cell proliferation by arresting the cell cycle, promoting apoptosis, and reducing OXPHOS via circKIF20B/miR-615-3p/MEF2A axis in NSCLC.

16.
Hematol Oncol ; 41(3): 380-388, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36680513

RESUMO

Prognostic nutritional index (PNI), comprised of serum albumin level and lymphocyte count, is associated with the prognosis of several malignant diseases, while the prognostic value of PNI in extranodal natural killer/T cell lymphoma, nasal type (ENKTL) remains unclear. This retrospective multicenter study aimed to investigate the value of PNI in predicting the prognosis of newly diagnosed ENKTL patients by using propensity score matched analysis (PSM). A total of 1022 newly diagnosed ENKTL patients were retrieved from Huaihai Lymphoma Working Group and clinicopathological variables were collected. MaxStat analysis was used to calculate the optimal cut-off points of PNI and other continuous variables. The median age at diagnosis was 47 years and 69.4% were males, with the 5-year OS of 71.7%. According to the MaxStat analysis, 41 was the optimal cut-off point for PNI. The Pseudo R2 before matching was 0.250, and it decreased to less than 0.019 after matching. Confounding factors of the two groups were well balanced after PSM. Multivariable analysis revealed that PNI, Korean Prognostic Index (KPI), eastern cooperative oncology group performance status (ECOG PS), the prognostic index of natural killer lymphoma (PINK) and hemoglobin were independent prognostic factors for ENKTL. The results of subgroup analysis demonstrated that patients with low PNI could predict worse prognosis and re-stratify patients in ECOG PS ≥ 2, EBER-positive, the International Prognostic Index (IPI) (HIR + HR), and PINK (HR) groups. PNI combined with IPI, PINK and KPI could improve the prediction efficiency. In conclusion, PNI could accurately stratify the prognosis of ENKTL by PSM analysis and patients with low PNI had poorer prognosis.


Assuntos
Linfoma Extranodal de Células T-NK , Avaliação Nutricional , Masculino , Humanos , Feminino , Prognóstico , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/terapia , Linfoma Extranodal de Células T-NK/metabolismo , Pontuação de Propensão , Células Matadoras Naturais/metabolismo , Estudos Retrospectivos
17.
Ann Hematol ; 102(6): 1433-1442, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37074377

RESUMO

Controlling nutritional status (CONUT) score as an original nutritional assessment tool can be used to assess the prognosis of patients with a variety of malignancies. However, the predictive power of CONUT in extranodal natural killer/T cell lymphoma (ENKTL) patients has never been demonstrated. Our retrospective multicenter study aimed to explore the prognostic value of CONUT in newly diagnosed ENKTL. A total of 1085 newly diagnosed ENKTL patients between 2003 and 2021 were retrospectively retrieved. Cox proportional hazard model was used to explore the prognostic factors of overall survival (OS). The survival rate of ENKTL was evaluated using Kaplan-Meier analysis, and log-rank test was applied to the difference between groups. We investigated the prognostic performance of CONUT, the International Prognostic Index (IPI), the Korean Prognostic Index (KPI), and the Prognostic Index of Natural Killer Cell Lymphoma (PINK) using the receiver operating characteristic (ROC) curve and decision curve analysis (DCA). The median age at diagnosis for the whole cohort was 47 years, and the male to female ratio was 2.2:1. The 5-year OS for all patients was 72.2%. Multivariable analysis showed that CONUT, age, bone marrow involvement, ECOG PS score, and Chinese Southwest Oncology Group and Asia Lymphoma Study Group ENKTL stage were identified as independent predictive factors for OS. Based on multivariable results, a prognostic nomogram was developed. Subgroup analysis demonstrated that patients with severe malnutrition had poorest clinical outcome. In addition, ROC curves and DCA analysis proved that compared with IPI, KPI, and PINK models, the CONUT score-based nomogram showed a better prognostic predictive efficiency of ENKTL. CONUT could effectively stratify the prognosis of ENKTL and the proposed nomogram based on CONUT was an effective prognostic model for prediction.


Assuntos
Linfoma Extranodal de Células T-NK , Nomogramas , Humanos , Masculino , Feminino , Prognóstico , Estado Nutricional , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/terapia , Estudos Retrospectivos , Células Matadoras Naturais/patologia
18.
Cell Mol Biol Lett ; 28(1): 90, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936104

RESUMO

BACKGROUND: The pulmonary surfactant that lines the air-liquid surface within alveoli is a protein-lipid mixture essential for gas exchange. Surfactant lipids and proteins are synthesized and stored in the lamellar body (LB) before being secreted from alveolar type II (AT2) cells. The molecular and cellular mechanisms that regulate these processes are incompletely understood. We previously identified an essential role of general control of amino acid synthesis 5 like 1 (GCN5L1) and the biogenesis of lysosome-related organelle complex 1 subunit 1 (BLOS1) in surfactant system development in zebrafish. Here, we explored the role of GCN5L1 in pulmonary surfactant regulation. METHOD: GCN5L1 knockout cell lines were generated with the CRISPR/Cas9 system. Cell viability was analyzed by MTT assay. Released surfactant proteins were measured by ELISA. Released surfactant lipids were measured based on coupled enzymatic reactions. Gene overexpression was mediated through lentivirus. The RNA levels were detected through RNA-sequencing (RNA-seq) and quantitative reverse transcription (qRT)- polymerase chain reaction (PCR). The protein levels were detected through western blotting. The cellular localization was analyzed by immunofluorescence. Morphology of the lamellar body was analyzed through transmission electron microscopy (TEM), Lysotracker staining, and BODIPY phosphatidylcholine labeling. RESULTS: Knocking out GCN5L1 in MLE-12 significantly decreased the release of surfactant proteins and lipids. We detected the downregulation of some surfactant-related genes and misregulation of the ROS-Erk-Foxo1-Cebpα axis in mutant cells. Modulating the activity of the axis or reconstructing the mitochondrial expression of GCN5L1 could partially restore the expression of these surfactant-related genes. We further showed that MLE-12 cells contained many LB-like organelles that were lipid enriched and positive for multiple LB markers. These organelles were smaller in size and accumulated in the absence of GCN5L1, indicating both biogenesis and trafficking defects. Accumulated endogenous surfactant protein (SP)-B or exogenously expressed SP-B/SP-C in adenosine triphosphate-binding cassette transporterA3 (ABCA3)-positive organelles was detected in mutant cells. GCN5L1 localized to the mitochondria and LBs. Reconstruction of mitochondrial GCN5L1 expression rescued the organelle morphology but failed to restore the trafficking defect and surfactant release, indicating specific roles associated with different subcellular localizations. CONCLUSIONS: In summary, our study identified GCN5L1 as a new regulator of pulmonary surfactant that plays a role in the biogenesis and positioning/trafficking of surfactant-containing LBs.


Assuntos
Surfactantes Pulmonares , Animais , Camundongos , Células Epiteliais Alveolares/metabolismo , Corpos Lamelares , Lipídeos , Surfactantes Pulmonares/metabolismo , RNA , Tensoativos , Peixe-Zebra/metabolismo
19.
J Biopharm Stat ; 33(6): 859-874, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36749066

RESUMO

Oncology has been one of the most active therapeutic areas in medicinal products development. Despite this fact, few drugs have been approved for use in pediatric cancer patients when compared to the number approved for adults with cancer. This disparity could be attributed to the fact that many oncology drugs have had orphan drug designation and were exempt from Pediatric Research Equity Act (PREA) requirements. On August 18, 2017, the RACE for Children Act, i.e. Research to Accelerate Cures and Equity Act, was signed into law as Title V of the 2017 FDA Reauthorization Act (FDARA) to amend the PREA. Pediatric investigation is now required if the drug or biological product is intended for the treatment of an adult cancer and directed at a molecular target that FDA determines to be "substantially relevant to the growth or progression of a pediatric cancer." This paper discusses the specific considerations in clinical trial designs and statistical methodologies to be implemented in oncology pediatric clinical programs.


Assuntos
Neoplasias , Adulto , Humanos , Criança , Estados Unidos , Neoplasias/tratamento farmacológico , Oncologia , Desenvolvimento de Medicamentos , Aprovação de Drogas , Produção de Droga sem Interesse Comercial , United States Food and Drug Administration
20.
J Biopharm Stat ; 33(6): 844-858, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36476267

RESUMO

In typical clinical development programs, a new drug is first developed for the adult use. Drugs are often approved for adult use or in the process of obtaining approval in adults in the target indication before pediatric development is initiated. In designing the first pediatric clinical trial, one of the challenges is to select the initial dose to be tested. The ICH E11 R1 guidance advises that chronologic age alone may not always be the most appropriate categorical determinant to define developmental subgroups in pediatric studies. In this manuscript, the approaches to utilize available data in adults related to those factors beyond age to inform the starting dose selection in pediatric drug development are discussed. Practical considerations and approaches are provided for informing pediatric starting dose. Additional considerations to use pre-clinical information are provided in the case when adult information is limited or not available.


Assuntos
Desenvolvimento de Medicamentos , Cálculos da Dosagem de Medicamento , Criança , Humanos , Projetos de Pesquisa
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