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1.
Opt Express ; 32(9): 16307-16318, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859261

RESUMO

Aiming at the difficulty of traditional chaotic-shift-keying (CSK) systems in resisting return map attacks, we propose an optical chaotic communication system based on time-delayed shift keying and common-signal-induced synchronization. This scheme combines amplified spontaneous emission (ASE) noise, phase modulator (PM), and fiber Bragg grating (FBG) to achieve dual masking in both intensity and phase fields, achieving 10Gb/s information transmission. A common-signal-induced method is used to achieve the synchronization of the system. Moreover, by shifting the time delay as the message-feeding method, the return map attack is effectively resisted, to prevent the amplitude and frequency information of the chaotic attractor from being exposed. In terms of confidentiality and communication performance, this scheme demonstrates good performance of time delay signatures (TDSs) concealment and long-distance transmission capability. In addition, this scheme maintains high sensitivity to key parameters and achieves better confidentiality while increasing the key space.

2.
Infect Agent Cancer ; 19(1): 21, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693556

RESUMO

AIMS: This study compared the prevalences of metabolic syndrome and of cardiac or kidney comorbidities among patients with hepatocellular carcinoma (HCC) associated with metabolic dysfunction-related fatty liver disease (MAFLD), chronic infection with hepatitis B or C virus (HBV or HCV), or the combination of MAFLD and chronic HBV infection. METHODS: Medical records were retrospectively analyzed for patients with HCC who underwent hepatectomy between March 2013 and March 2023. Patients with HCC of different etiologies were compared in terms of their clinicodemographic characteristics and laboratory data before surgery. RESULTS: Of the 2422 patients, 1,822 (75.2%) were chronically infected with HBV without MAFLD and HCV, 415 (17.2%) had concurrent MAFLD and chronic HBV infection but no HCV infection, 121 (5.0%) had MAFLD without hepatitis virus infection, and 64 (2.6%) were chronically infected with HCV in the presence or absence of MAFLD and HBV infection. Compared to patients chronically infected with HBV without MAFLD and HCV, those with MAFLD but no hepatitis virus infection showed significantly lower prevalence of cirrhosis, ascites, portal hypertension, alpha-fetoprotein concentration ≥ 400 ng/mL, tumor size > 5 cm, multinodular tumors and microvascular invasion. Conversely, they showed significantly higher prevalence of metabolic syndrome, hypertension, type 2 diabetes, abdominal obesity, history of cardiovascular disease, T-wave alterations, hypertriglyceridemia and hyperuricemia, as well as higher risk of arteriosclerotic cardiovascular disease. Compared to patients with MAFLD but no hepatitis virus infection, those with concurrent MAFLD and chronic infection with HBV showed significantly higher prevalence of cirrhosis, ascites and portal hypertension, but significantly lower prevalence of hypertension and history of cardiovascular disease. Compared to patients with other etiologies, those chronically infected with HCV in the presence or absence of MAFLD and HBV infection, showed significantly higher prevalence of cirrhosis, portal hypertension, ascites, and esophagogastric varices. CONCLUSION: Patients with HCC associated with MAFLD tend to have a background of less severe liver disease than those with HCC of other etiologies, but they may be more likely to suffer metabolic syndrome or comorbidities affecting the heart or kidneys.

3.
Comput Struct Biotechnol J ; 24: 247-257, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38617891

RESUMO

Objectives: Combination therapy of lenvatinib and immune checkpoint inhibitors (CLICI) has emerged as a promising approach for managing unresectable hepatocellular carcinoma (HCC). However, the response to such treatment is observed in only a subset of patients, underscoring the pressing need for reliable methods to identify potential responders. Materials & methods: This was a retrospective analysis involving 120 patients with unresectable HCC. They were divided into training (n = 72) and validation (n = 48) cohorts. We developed an interpretable deep learning model using multiphase computed tomography (CT) images to predict whether patients will respond or not to CLICI treatment, based on the Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST v1.1). We evaluated the models' performance and analyzed the impact of each CT phase. Critical regions influencing predictions were identified and visualized through heatmaps. Results: The multiphase model outperformed the best biphase and uniphase models, achieving an area under the curve (AUC) of 0.802 (95% CI = 0.780-0.824). The portal phase images were found to significantly enhance the model's predictive accuracy. Heatmaps identified six critical features influencing treatment response, offering valuable insights to clinicians. Additionally, we have made this model accessible via a web server at http://uhccnet.com/ for ease of use. Conclusions: The integration of multiphase CT images with deep learning-generated heatmaps for predicting treatment response provides a robust and practical tool for guiding CLICI therapy in patients with unresectable HCC.

4.
J Synchrotron Radiat ; 31(Pt 2): 378-384, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241124

RESUMO

An integrated computer software system for macromolecular crystallography (MX) data collection at the BL02U1 and BL10U2 beamlines of the Shanghai Synchrotron Radiation Facility is described. The system, Finback, implements a set of features designed for the automated MX beamlines, and is marked with a user-friendly web-based graphical user interface (GUI) for interactive data collection. The Finback client GUI can run on modern browsers and has been developed using several modern web technologies including WebSocket, WebGL, WebWorker and WebAssembly. Finback supports multiple concurrent sessions, so on-site and remote users can access the beamline simultaneously. Finback also cooperates with the deployed experimental data and information management system, the relevant experimental parameters and results are automatically deposited to a database.

5.
Eur J Med Chem ; 264: 115984, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38043490

RESUMO

Fatty-acid binding protein 4 (FABP4) presents an attractive target for therapeutic intervention in metabolic and inflammatory diseases in recent years. However, highly similar three-dimensional structures and fatty acid binding ability of multiple FABP family members pose a significant challenge in design of FABP4-selective inhibitors. Particularly, inhibition of FABP3 raises safety concerns such as cardiac dysfunction and exercise intolerance. Here, we reported the discovery of new FABP4 inhibitors with high selectivity over FABP3 by exploiting the little structural difference in the ligand binding pockets of FABP4 and FABP3. On the basis of our previously reported FABP4 inhibitors with nanomolar potency, different substituents were further introduced to perfectly occupy two sub-pockets of FABP4 that are distinct from those of FABP3. Remarkably, a single methyl group introduction leads to the discovery of compound C3 that impressively exhibits a 601-fold selectivity over FABP3 when maintained nanomolar binding affinity for FABP4. Moreover, C3 also shows good metabolic stability and potent cellular anti-inflammatory activity, making it a promising inhibitor for further development. Therefore, the present study highlights the utility of the structure-based rational design strategy for seeking highly selective and potent inhibitors of FABP4 and the importance of identifying the appropriate subsite as well as substituent for gaining the desired selectivity.


Assuntos
Anti-Inflamatórios , Proteínas de Ligação a Ácido Graxo
6.
Hepatol Int ; 18(1): 73-90, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159218

RESUMO

PURPOSE: Cytokeratin 19-positive cancer stem cells (CK19 + CSCs) and their tumor-associated macrophages (TAMs) have not been fully explored yet in the hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). EXPERIMENTAL DESIGN: Single-cell RNA sequencing was performed on the viable cells obtained from 11 treatment-naïve HBV-associated HCC patients, including 8 CK19 + patients, to elucidate their transcriptomic landscape, CK19 + CSC heterogeneity, and immune microenvironment. Two in-house primary HCC cohorts (96 cases-related HBV and 89 cases with recurrence), TCGA external cohort, and in vitro and in vivo experiments were used to validate the results. RESULTS: A total of 64,581 single cells derived from the human HCC and adjacent normal tissues were sequenced, and 11 cell types were identified. The result showed that CK19 + CSCs were phenotypically and transcriptionally heterogeneous, co-expressed multiple hepatics CSC markers, and were positively correlated with worse prognosis. Moreover, the SPP1 + TAMs (TAM_SPP1) with strong M2-like features and worse prognosis were specifically enriched in the CK19 + HCC and promoted tumor invasion and metastasis by activating angiogenesis. Importantly, matrix metalloproteinase 9 (MMP9) derived from TAM_SPP1, as the hub gene of CK19 + HCC, was activated by the VEGFA signal. CONCLUSIONS: This study revealed the heterogeneity and stemness characteristics of CK19 + CSCs and specific immunosuppressive TAM_SPP1 in CK19 + HCC. The VEGFA signal can activate TAM_SPP1-derived MMP9 to promote the invasion and metastasis of CK19 + HCC tumors. This might provide novel insights into the clinical treatment of HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Vírus da Hepatite B/genética , Metaloproteinase 9 da Matriz/genética , Queratina-19/genética , Queratina-19/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Células-Tronco Neoplásicas , Análise de Sequência de RNA , Microambiente Tumoral , Osteopontina/genética , Osteopontina/metabolismo
7.
Eur J Med Chem ; 262: 115893, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37918035

RESUMO

Phosphodiesterase-4 (PDE4) and PDE5 responsible for the hydrolysis of intracellular cAMP and cGMP, respectively, are promising targets for therapeutic intervention in a wide variety of diseases. Here, we report the discovery of novel, drug-like PDE4 inhibitors by performing a high-throughput drug repurposing screening of 2560 approved drugs and drug candidates in clinical trial studies. It allowed us to identify eight potent PDE4 inhibitors with IC50 values ranging from 0.41 to 2.46 µM. Crystal structures of PDE4 in complex with four compounds, namely ethaverine hydrochloride (EH), benzbromarone (BBR), CX-4945, and CVT-313, were further solved to elucidate molecular mechanisms of action of these new inhibitors, providing a solid foundation for optimizing the inhibitors to improve their potency as well as selectivity. Unexpectedly, selectivity profiling of other PDE subfamilies followed by crystal structure determination revealed that CVT-313 was also a potent PDE5 inhibitor with a binding mode similar to that of tadalafil, a marketed PDE5 inhibitor, but distinctively different from the binding mode of CVT-313 with PDE4. Structure-guided modification of CVT-313 led to the discovery of a new inhibitor, compound 2, with significantly improved inhibitory activity as well as selectivity towards PDE5 over PDE4. Together, these results highlight the utility of the drug repurposing in combination with structure-based drug design in identifying novel inhibitors of PDE4 and PDE5, which provides a prime example for efficient discovery of drug-like hits towards a given target protein.


Assuntos
Inibidores da Fosfodiesterase 4 , Inibidores da Fosfodiesterase 5 , Inibidores da Fosfodiesterase 5/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Inibidores da Fosfodiesterase 4/farmacologia , Reposicionamento de Medicamentos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo
8.
J Hepatocell Carcinoma ; 10: 1881-1895, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901717

RESUMO

Background: Hepatocellular carcinoma (HCC) patients who are at significant risk of tumor recurrence and mortality can benefit from postoperative adjuvant transarterial chemoembolization (PA-TACE). However, the benefits of PA-TACE remain unclear. Herein, we aimed to develop a model for predicting the prognosis of HBV-related patients who undergo PA-TACE and endeavored to guide individualized clinical treatment. Methods: We included 432 HBV-related patients who underwent PA-TACE after curative resection were included. The dataset was divided into a training set (n=216) and an internal validation set (n=216). For identifying independent risk factors, the least absolute shrinkage and selection operator and univariate and multivariate Cox analyses were performed. We derived a prognostic model from the training set that was internally validated. The concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve, and risk stratification were used to evaluate the performance of the nomogram. Results: Patients undergoing PA-TACE had significantly longer overall survival (OS) than those who did not undergo PA-TACE. Age, albumin levels, macrovascular invasion, tumor size, and, stages of Barcelona Clinic Liver Cancer were identified as independent risk variables and concluded into the nomogram to predict the OS of HBV-related patients who received PA-TACE. The nomogram's C-index values OS were 0.710 and 0.652 in the training and internal validation sets, respectively. Both time-dependent AUC and the calibration curve showed good discrimination and model fitness. The risk score -0.12 was kept as the cut-off value that would accurately divide patients into high-risk and low-risk groups; furthermore, the Kaplan-Meier curve showed a high discriminative ability of the model. Conclusion: We developed a predictive model. comprising a formula and nomogram to predict the OS and provide risk stratification for HBV-related patients undergoing PA-TACE, which could contribute to suitable treatment options for this patient population.

9.
Nat Commun ; 14(1): 6463, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833261

RESUMO

The persistent pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants accentuates the great demand for developing effective therapeutic agents. Here, we report the development of an orally bioavailable SARS-CoV-2 3C-like protease (3CLpro) inhibitor, namely simnotrelvir, and its preclinical evaluation, which lay the foundation for clinical trials studies as well as the conditional approval of simnotrelvir in combination with ritonavir for the treatment of COVID-19. The structure-based optimization of boceprevir, an approved HCV protease inhibitor, leads to identification of simnotrelvir that covalently inhibits SARS-CoV-2 3CLpro with an enthalpy-driven thermodynamic binding signature. Multiple enzymatic assays reveal that simnotrelvir is a potent pan-CoV 3CLpro inhibitor but has high selectivity. It effectively blocks replications of SARS-CoV-2 variants in cell-based assays and exhibits good pharmacokinetic and safety profiles in male and female rats and monkeys, leading to robust oral efficacy in a male mouse model of SARS-CoV-2 Delta infection in which it not only significantly reduces lung viral loads but also eliminates the virus from brains. The discovery of simnotrelvir thereby highlights the utility of structure-based development of marked protease inhibitors for providing a small molecule therapeutic effectively combatting human coronaviruses.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Feminino , Masculino , Animais , Humanos , Ratos , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Inibidores de Proteases/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Antivirais/química , Inibidores Enzimáticos
10.
Bioorg Chem ; 140: 106802, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37666112

RESUMO

Cyclic GMP-AMP synthase (cGAS) plays an important role in the inflammatory response. It has been reported that aberrant activation of cGAS is associated with a variety of immune-mediated inflammatory disorders. The development of small molecule inhibitors of cGAS has been considered as a promising therapeutic strategy for the diseases. Flavonoids, a typical class of natural products, are known for their anti-inflammatory activities. Although cGAS is closely associated with inflammation, the potential effects of natural flavonoid compounds on cGAS have been rarely studied. Therefore, we screened an in-house natural flavonoid library by pyrophosphatase (PPiase) coupling assay and identified novel cGAS inhibitors baicalein and baicalin. Subsequently, crystal structures of the two natural flavonoids in complex with human cGAS were determined, which provide mechanistic insight into the anti-inflammatory activities of baicalein and baicalin at the molecular level. After that, a virtual screening based on the crystal structures of baicalein and baicalin in complex with human cGAS was performed. As a result, compound C20 was identified to inhibit both human and mouse cGAS with IC50 values of 2.28 and 1.44 µM, respectively, and its detailed interactions with human cGAS were further revealed by the X-ray crystal structure determination. These results demonstrate the potential of natural products used as hits in drug discovery and provide valuable hints for further development of cGAS inhibitors.


Assuntos
Produtos Biológicos , Flavonoides , Nucleotidiltransferases , Animais , Humanos , Camundongos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Descoberta de Drogas , Flavonoides/química , Flavonoides/farmacologia , Nucleotidiltransferases/antagonistas & inibidores
11.
Int J Mol Sci ; 24(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298537

RESUMO

The current understanding of the prognostic significance of natural killer (NK) cells and their tumor microenvironment (TME) in hepatocellular carcinoma (HCC) is limited. Thus, we screened for NK-cell-related genes by single-cell transcriptome data analysis and developed an NK-cell-related gene signature (NKRGS) using multi-regression analyses. Patients in the Cancer Genome Atlas cohort were stratified into high- and low-risk groups according to their median NKRGS risk scores. Overall survival between the risk groups was estimated using the Kaplan-Meier method, and a NKRGS-based nomogram was constructed. Immune infiltration profiles were compared between the risk groups. The NKRGS risk model suggests significantly worse prognoses in patients with high NKRGS risk (p < 0.05). The NKRGS-based nomogram showed good prognostic performance. The immune infiltration analysis revealed that the high-NKRGS-risk patients had significantly lower immune cell infiltration levels (p < 0.05) and were more likely to be in an immunosuppressive state. The enrichment analysis revealed that immune-related and tumor metabolism pathways highly correlated with the prognostic gene signature. In this study, a novel NKRGS was developed to stratify the prognosis of HCC patients. An immunosuppressive TME coincided with the high NKRGS risk among the HCC patients. The higher KLRB1 and DUSP10 expression levels correlated with the patients' favorable survival.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Células Matadoras Naturais , Imunossupressores , Nomogramas , Microambiente Tumoral/genética , Fosfatases de Especificidade Dupla , Fosfatases da Proteína Quinase Ativada por Mitógeno
12.
Int J Mol Sci ; 24(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37239980

RESUMO

The papain-like protease (PLpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays a critical role in the proteolytic processing of viral polyproteins and the dysregulation of the host immune response, providing a promising therapeutic target. Here, we report the structure-guide design of novel peptidomimetic inhibitors covalently targeting SARS-CoV-2 PLpro. The resulting inhibitors demonstrate submicromolar potency in the enzymatic assay (IC50 = 0.23 µM) and significant inhibition of SARS-CoV-2 PLpro in the HEK293T cells using a cell-based protease assay (EC50 = 3.61 µM). Moreover, an X-ray crystal structure of SARS-CoV-2 PLpro in complex with compound 2 confirms the covalent binding of the inhibitor to the catalytic residue cysteine 111 (C111) and emphasizes the importance of interactions with tyrosine 268 (Y268). Together, our findings reveal a new scaffold of SARS-CoV-2 PLpro inhibitors and provide an attractive starting point for further optimization.


Assuntos
COVID-19 , Peptidomiméticos , Humanos , Peptidomiméticos/farmacologia , Células HEK293 , SARS-CoV-2 , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , Antivirais/farmacologia , Antivirais/química
13.
Expert Rev Gastroenterol Hepatol ; 17(5): 499-507, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36975382

RESUMO

OBJECTIVES: To analyze prognostic value of total tumor volume (TTV) and tumor burden score (TBS) in surgically treated patients with hepatocellular carcinoma and concurrent fatty liver disease and hepatitis B virus (FLD-HCC). METHODS: FLD-HCC patients who treated with hepatectomy from 2010 to 2018 were analyzed. Prognostic performance of TTV and TBS was determined by ROC analysis. Patients were stratified into low and high tumor burden by optimal cutoff value of 113.4 cm3 for TTV or 6.3 points for TBS. Survival rates were compared between subgroups and independent risk factors were identified by Cox regression. Correlation between TTV and TBS was evaluated. RESULTS: This study enrolled 342 FLD-HCC patients. Survival was significantly higher among patients with low tumor burden than among those with high tumor burden (p < 0.001). High TTV and TBS were independent risk factors for poor survival of FLD-HCC (HR: 3.27 (2.17-4.93) and 3.48 (2.31-5.26), respectively, all p < 0.001). ROC analyses revealed that TTV and TBS had comparable discriminative ability in stratifying overall and recurrence-free survival of FLD-HCC. Correlation analysis revealed a strong correlation between TTV and TBS. CONCLUSIONS: Both TTV and TBS have comparable prognostic value and high TTV/TBS predicts poor survival of patients with FLD-HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Vírus da Hepatite B , Carga Tumoral , Taxa de Sobrevida , Estudos Retrospectivos , Prognóstico , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/cirurgia , Hepatectomia
14.
PLoS Negl Trop Dis ; 17(1): e0011012, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638133

RESUMO

BACKGROUND: This study aimed to determine the impact of co-infection of Clonorchis sinensis (CS) and hepatitis B virus (HBV) on the prognosis of patients with hepatocellular carcinoma (HCC) following hepatectomy. METHODS: The clinicopathological information of 946 patients with HCC following hepatectomy was retrospectively analyzed. The patients were divided into four groups depending on whether they had CS infection and/or HBV infection: double-negative group (infected with neither CS nor HBV), simple CS group (infected with only CS), simple HBV group (infected with only HBV), and double-positive group (co-infected with CS and HBV). Kaplan-Meier curves were used to evaluate the overall survival (OS) and recurrence-free survival (RFS), while log-rank tests were used to compare survival rates. Further, Cox regression was used to perform both univariate and multivariate survival analyses to identify variables linked to the prognosis of HCC. RESULTS: The median overall survival (OS) and recurrence-free survival (RFS) in the double-positive, simple CS, simple HBV, and double-negative groups were 27 months and 9 months, 20 months and 7 months, 44 months and 12 months, and 42 months and 17 months, respectively. The double-positive group's 1-year, 3-year, and 5-year OS and RFS rates were 79.2% and 46.9%, 62.6% and 28.4%, 47.8%, and 12.2%, respectively. The simple CS group's 1-year, 3-year, and 5-year OS and RFS rates were 86.3% and 41.5%, 56.5% and 27.7%, 50.2%, and 18.5%, respectively. The simple HBV group's 1-year, 3-year, and 5-year OS and RFS rates were 89.8% and 56.0%, 72.5% and 30.5%, 63.8%, and 19.9%, respectively. The double-negative group's 1-year, 3-year, and 5-year OS and RFS rates were 91.5% and 62.3%, 76.1% and 32.9%, 64.0%, and 22.4%, respectively. Further, according to a Cox multivariate analysis, tumor size (> 5cm), Edmonson grade (III-IV), BCLC-C stage, and tumor satellite focus were independent risk factors for RFS and OS in patients with HCC. CONCLUSION: Patients with HCC and Clonorchis sinensis infection experience a poor prognosis after hepatectomy, regardless of whether they are co-infected with HBV.


Assuntos
Carcinoma Hepatocelular , Clonorchis sinensis , Hepatite B , Neoplasias Hepáticas , Humanos , Animais , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos , Hepatectomia , Intervalo Livre de Doença , Prognóstico , Hepatite B/complicações
15.
Biochem Pharmacol ; 207: 115376, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513142

RESUMO

Molecular chaperone HSP90 has been considered as a promising target for anti-cancer drug development for years. However, due to the heat shock response induced by the ATP competitive inhibitors against HSP90, the therapeutic efficacies of the compounds are compromised, which consequently restricts the clinical use of HSP90-targeted inhibitors. Therefore, there is a need to discover novel HSP90-targeted modulators which exhibit acceptable inhibition activity against the chaperone and do not induce significant heat shock response in the meantime. Here in this study, we firstly developed a tip-based affinity selection-mass spectrometry platform with optimized experimental conditions/parameters for HSP90-targeted active compound screening, and then applied it to fish out inhibitors against HSP90 from a collection of 2,395 compounds composed of FDA-approved drugs and drug candidates. Dipyridamole, which acts as an anti-thrombotic agent by modulating multiple targets and has a long history of safe use, was identified to interact with HSP90's N-terminal domain. The following conducted biophysical and biochemical experiments demonstrated that Dipyridamole could bind to HSP90's ATP binding pocket and function as an ATP competitive inhibitor of the chaperone. Finally, cellular-based assays including CESTA, cell viability assessment and proteomic analysis etc. were performed to evaluate whether the interaction between HSP90 and Dipyridamole contributes to the anti-tumor effects of the compound. We then found that Dipyridamole inhibits the growth and proliferation of human cancer cells by downregulating cell cycle regulators and upregulating apoptotic cell signaling, which are potentially mediated by the binding of Dipyridamole to HSP90 and to PDEs (phosphodiesterases), respectively.


Assuntos
Dipiridamol , Proteínas de Choque Térmico HSP90 , Neoplasias , Animais , Humanos , Trifosfato de Adenosina/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Dipiridamol/farmacologia , Proteínas de Choque Térmico HSP90/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Proteômica , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo
16.
Mitochondrial DNA B Resour ; 7(11): 1890-1892, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36340921

RESUMO

Eleutherococcus nodiflorus (Dunn) S. Y. Hu is a momentous medicinal plant belonging to the Araliaceae family. In the current investigation, we determined the complete chloroplast genome of E. nodiflorus and analyzed the phylogenetic relationship among Eleutherococcus plants. The chloroplast genome of E. nodiflorus exhibited a typical quadripartite structure with a full length of 156,770 bp, including 133 genes, containing 88 protein-coding genes, 8 rRNA genes, 37 tRNA genes, and 1 presumed pseudogene (ycf1). The overall GC content observed was 37.95%, with the highest GC content of 43.02% found in the IR region. Comparative genome analysis revealed five highly variable regions among Eleutherococcus species, providing potential markers for further investigations on species identification and population genetics. A total of 44 small simple repeats were identified throughout the chloroplast genome of E. nodiflorus. The phylogenetic analysis indicated a sister relationship between E. nodiflorus and E. eleutheristylus, suggesting a close genetic relationship between the two Eleutherococcus plants. These results enhance the understanding of the plant evolution within Eleutherococcus plants and provide basic genetic resources for the development of species identification and investigation of population genetic diversity of the Eleutherococcus genus and Araliaceae.

17.
Angew Chem Int Ed Engl ; 61(52): e202212378, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36308706

RESUMO

The coronavirus papain-like protease (PLpro ) plays an important role in the proteolytic processing of viral polyproteins and the dysregulation of the host immune response, providing a promising therapeutic target. However, the development of inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PLpro is challenging owing to the restricted S1/S2 sites in the substrate binding pocket. Here we report the discovery of two activators of SARS-CoV-2 PLpro and the identification of the unique residue, cysteine 270 (C270), as an allosteric and covalent regulatory site for the activators. This site is also specifically modified by glutathione, resulting in protease activation. Furthermore, a compound was found to allosterically inhibit the protease activity by covalent binding to C270. Together, these results elucidate an unrevealed molecular mechanism for allosteric modulation of SARS-CoV-2 PLpro and provid a novel site for allosteric inhibitors design.


Assuntos
COVID-19 , Proteases Semelhantes à Papaína de Coronavírus , Humanos , Cisteína , Proteínas Virais/metabolismo , SARS-CoV-2/metabolismo , Peptídeo Hidrolases/metabolismo , Antivirais/farmacologia , Inibidores de Proteases
18.
Bioorg Chem ; 128: 106109, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36049322

RESUMO

Zika virus (ZIKV) has been a serious public health problem, and there is no vaccine or drug approved for the prevention or treatment of ZIKV yet. The ZIKV NS2B/NS3 protease plays an important role in processing the virus precursor polyprotein and is thus a promising target for antiviral drugs development. In order to discover novel inhibitors of this protease, we carried out a fragment-based hit screening and characterized protein-inhibitor interactions using the X-ray crystallography together with isothermal titration calorimetry. We reported two high-resolution crystal structures of the protease (bZiProC143S) in complex with an active fragment as well as a tetrapeptide, revealing that there is domain swapping in the protein structures and two ligands only occupy the substrate-binding pocket of one copy in a symmetric unit. Based on the detailed binding modes of two ligands revealed by crystal structures, we designed a novel inhibitor which inhibits the NS2B/NS3 protease with a higher potency than the fragment and possesses a higher ligand-binding efficiency and a comparable IC50 compared to the tetrapeptide. These results thus provide a structural basis and valuable hint for development of more potent inhibitors of the ZIKV NS2B/NS3 protease.


Assuntos
Infecção por Zika virus , Zika virus , Antivirais/química , Humanos , Ligantes , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/química , Ligação Proteica , Conformação Proteica , Proteínas não Estruturais Virais/metabolismo , Zika virus/metabolismo
19.
Clin Lab ; 68(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36125138

RESUMO

BACKGROUND: Myelodysplastic syndromes (MDS) are a class of myeloid neoplasms featuring inefficient maturation and differentiation of hematopoietic cells, blood cytopenia, and a high risk of leukemia onset. The diagnosis of MDS remains a challenging task owing to its complexity, heterogeneity, and the lack of specific characteristics. METHODS: To look for an easy and inexpensive diagnostic method for MDS, we tried to establish an FCM scoring systems (FCSS) with a combination of antibodies for diagnosis and prognostic stratification of MDS. This FCSS adopted four parameters; i.e., the frequency of myeloblasts in nucleated cells, the ratio between pro-B cells and CD117+ cells, the ratio of CD45 mean fluorescence intensity between lymphocytes and myeloblasts, and the ratio of SSC peak values between mature granulocytes and lymphocytes. RESULTS: We tested the correlation between the total FCSS score with conventional IPSS-R. Additionally, the correlation between the score of each FCSS parameter and IPSS-R was also evaluated. We found that total FCSS score had a positive correlation with IPSS-R, while FCSS parameter 1 and 4 were also correlated with IPSS-R. Furthermore, this FCSS had a sound sensitivity and specificity in the diagnosis of MDS. CONCLUSIONS: The FCSS represents a convenient and affordable approach for the diagnosis and prognostic stratification of MDS.


Assuntos
Leucemia , Síndromes Mielodisplásicas , Compostos Férricos , Citometria de Fluxo/métodos , Humanos , Contagem de Leucócitos , Maltose/análogos & derivados , Síndromes Mielodisplásicas/diagnóstico , Prognóstico
20.
Oxid Med Cell Longev ; 2022: 2109891, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401922

RESUMO

Evidence reveals that propofol protects cells via suppressing excessive autophagy induced by hypoxia/reoxygenation (H/R). Previously, we found in a genome-wide microRNA profile analysis that several autophagy-related microRNAs were significantly altered during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH), but how these microRNAs work in P-PostH is still largely unknown. Here, we found that one of these microRNAs, microRNA-30b (miR-30b), in human umbilical vein endothelial cells (HUVECs) was downregulated by H/R treatment but significantly upregulated by 100 M propofol after H/R treatment. miR-30b showed similar changes in open heart surgery patients. By dual-luciferase assay, we found that Beclin-1 is the direct target of miR-30b. This conclusion was also supported by knockdown or overexpression of miR-30b. Further studies showed that miR-30b inhibited H/R-induced autophagy activation. Overexpression or knockdown of miR-30b regulated autophagy-related protein gene expression in vitro. To clarify the specific role of propofol in the inhibition of autophagy and distinguish the induction of autophagy from the damage of autophagy flux, we used bafilomycin A1. LC3-II levels were decreased in the group treated with propofol combined with bafilomycin A1 compared with the group treated with bafilomycin A1 alone after hypoxia and reoxygenation. Moreover, HUVECs transfected with Ad-mCherry-GFP-LC3b confirmed the inhibitory effect of miR-30b on autophagy flux. Finally, we found that miR-30b is able to increase the cellular viability under the H/R condition, partially mimicking the protective effect of propofol which suppressed autophagy via enhancing miR-30b and targeting Beclin-1. Therefore, we concluded that propofol upregulates miR-30b to repress excessive autophagy via targeting Beclin-1 under H/R condition. Thus, our results revealed a novel mechanism of the protective role of propofol during anesthesia. Clinical Trial Registration Number. This trial is registered with ChiCTR-IPR-14005470. The name of the trial register: Propofol Upregulates MicroRNA-30b to Repress Beclin-1 and Inhibits Excessive Autophagy and Apoptosis.


Assuntos
MicroRNAs , Propofol , Traumatismo por Reperfusão , Apoptose , Autofagia/genética , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipóxia , Isquemia , MicroRNAs/metabolismo , Propofol/farmacologia , Propofol/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo
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