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1.
iScience ; 27(6): 109932, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799563

RESUMO

Early identification of patients at high risk of delirium is crucial for its prevention. Our study aimed to develop machine learning models to predict delirium after cardiac surgery using intraoperative biosignals and clinical data. We introduced a novel approach to extract relevant features from continuously measured intraoperative biosignals. These features reflect the patient's overall or baseline status, the extent of unfavorable conditions encountered intraoperatively, and beat-to-beat variability within the data. We developed a soft voting ensemble machine learning model using retrospective data from 1,912 patients. The model was then prospectively validated with data from 202 additional patients, achieving a high performance with an area under the receiver operating characteristic curve of 0.887 and an accuracy of 0.881. According to the SHapley Additive exPlanation method, several intraoperative biosignal features had high feature importance, suggesting that intraoperative patient management plays a crucial role in preventing delirium after cardiac surgery.

2.
J Med Chem ; 66(24): 16783-16806, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38085679

RESUMO

The chromatin-associated protein WDR5 (WD repeat domain 5) is an essential cofactor for MYC and a conserved regulator of ribosome protein gene transcription. It is also a high-profile target for anti-cancer drug discovery, with proposed utility against both solid and hematological malignancies. We have previously discovered potent dihydroisoquinolinone-based WDR5 WIN-site inhibitors with demonstrated efficacy and safety in animal models. In this study, we sought to optimize the bicyclic core to discover a novel series of WDR5 WIN-site inhibitors with improved potency and physicochemical properties. We identified the 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one core as an alternative scaffold for potent WDR5 inhibitors. Additionally, we used X-ray structural analysis to design partially saturated bicyclic P7 units. These benzoxazepinone-based inhibitors exhibited increased cellular potency and selectivity and favorable physicochemical properties compared to our best-in-class dihydroisoquinolinone-based counterparts. This study opens avenues to discover more advanced WDR5 WIN-site inhibitors and supports their development as novel anti-cancer therapeutics.


Assuntos
Antineoplásicos , Repetições WD40 , Animais , Descoberta de Drogas , Antineoplásicos/farmacologia
3.
Front Cardiovasc Med ; 9: 849223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463761

RESUMO

Coronary artery calcium (CAC), which can be measured in various types of computed tomography (CT) examinations, is a hallmark of coronary artery atherosclerosis. However, despite the clinical value of CAC scores in predicting cardiovascular events, routine measurement of CAC scores is limited due to high cost, radiation exposure, and lack of widespread availability. It would be of great clinical significance if CAC could be predicted by electrocardiograms (ECGs), which are cost-effective and routinely performed during various medical checkups. We aimed to develop binary classification artificial intelligence (AI) models that predict CAC using only ECGs as input. Moreover, we aimed to address the generalizability of our model in different environments by externally validating our model on a dataset from a different institution. Among adult patients, standard 12-lead ECGs were extracted if measured within 60 days before or after the CAC scores, and labeled with the corresponding CAC scores. We constructed deep convolutional neural network models based on residual networks using only the raw waveforms of the ECGs as input, predicting CAC at different levels, namely CAC score ≥100, ≥400 and ≥1,000. Our AI models performed well in predicting CAC in the training and internal validation dataset [area under the receiver operating characteristics curve (AUROC) 0.753 ± 0.009, 0.802 ± 0.027, and 0.835 ± 0.024 for the CAC score ≥100, ≥400, and ≥1,000 model, respectively]. Our models also performed well in the external validation dataset (AUROC 0.718, 0.777 and 0.803 for the CAC score ≥100, ≥400, and ≥1,000 model, respectively), indicating that our model can generalize well to different but plausibly related populations. Model performance in terms of AUROC increased in the order of CAC score ≥100, ≥400, and ≥1,000 model, indicating that higher CAC scores might be associated with more prominent structural changes of the heart detected by the model. With our AI models, a substantial proportion of previously unrecognized CAC can be afforded with a risk stratification of CAC, enabling initiation of prophylactic therapy, and reducing the adverse consequences related to ischemic heart disease.

4.
Chem Commun (Camb) ; 58(36): 5490-5493, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35416212

RESUMO

A method for the in situ production of formaldehyde from dimethylsulfoxide, bromine, and cesium carbonate is reported for reactions with difluoroenolates and difluorobenzyl carbanions. This process also generates formaldehyde-d2 for the production of 2,2-difluoro-1,1-deuteroethanols. Mechanistic and computational studies further characterize the production of hydroxymethylated and hydroxydeuteromethylated difluorinated organic molecules.


Assuntos
Formaldeído , Ânions
5.
J Med Chem ; 63(2): 656-675, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31858797

RESUMO

WD repeat domain 5 (WDR5) is a member of the WD40-repeat protein family that plays a critical role in multiple chromatin-centric processes. Overexpression of WDR5 correlates with a poor clinical outcome in many human cancers, and WDR5 itself has emerged as an attractive target for therapy. Most drug-discovery efforts center on the WIN site of WDR5 that is responsible for the recruitment of WDR5 to chromatin. Here, we describe discovery of a novel WDR5 WIN site antagonists containing a dihydroisoquinolinone bicyclic core using a structure-based design. These compounds exhibit picomolar binding affinity and selective concentration-dependent antiproliferative activities in sensitive MLL-fusion cell lines. Furthermore, these WDR5 WIN site binders inhibit proliferation in MYC-driven cancer cells and reduce MYC recruitment to chromatin at MYC/WDR5 co-bound genes. Thus, these molecules are useful probes to study the implication of WDR5 inhibition in cancers and serve as a potential starting point toward the discovery of anti-WDR5 therapeutics.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Quinolonas/síntese química , Quinolonas/farmacologia , Repetições WD40/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/efeitos dos fármacos , Cromatina/genética , Cristalografia por Raios X , Desenho de Fármacos , Descoberta de Drogas , Repressão Epigenética/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade
6.
J Med Chem ; 62(24): 11232-11259, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31724864

RESUMO

The treatment of tumors driven by overexpression or amplification of MYC oncogenes remains a significant challenge in drug discovery. Here, we present a new strategy toward the inhibition of MYC via the disruption of the protein-protein interaction between MYC and its chromatin cofactor WD Repeat-Containing Protein 5. Blocking the association of these proteins is hypothesized to disrupt the localization of MYC to chromatin, thus disrupting the ability of MYC to sustain tumorigenesis. Utilizing a high-throughput screening campaign and subsequent structure-guided design, we identify small-molecule inhibitors of this interaction with potent in vitro binding affinity and report structurally related negative controls that can be used to study the effect of this disruption. Our work suggests that disruption of this protein-protein interaction may provide a path toward an effective approach for the treatment of multiple tumors and anticipate that the molecules disclosed can be used as starting points for future efforts toward compounds with improved drug-like properties.


Assuntos
Descoberta de Drogas , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Ácido Salicílico/química , Bibliotecas de Moléculas Pequenas/farmacologia , Sulfonamidas/farmacologia , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ligação Proteica , Conformação Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Repetições WD40
7.
Bioorg Med Chem Lett ; 25(13): 2720-5, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25987377

RESUMO

A series of substituted hydroxymethyl piperidine small molecule inhibitors of the protein-protein interaction between menin and mixed lineage leukemia 1 (MLL1) are described. Initial members of the series showed good inhibitory disruption of the menin-MLL1 interaction but demonstrated poor physicochemical and DMPK properties. Utilizing a structure-guided and iterative optimization approach key substituents were optimized leading to inhibitors with cell-based activity, improved in vitro DMPK parameters, and improved half-lives in rodent PK studies leading to MLPCN probe ML399. Ancillary off-target activity remains a parameter for further optimization.


Assuntos
Proteína de Leucina Linfoide-Mieloide/antagonistas & inibidores , Piperidinas/química , Piperidinas/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Técnicas In Vitro , Camundongos , Modelos Moleculares , Proteína de Leucina Linfoide-Mieloide/química , Piperidinas/farmacocinética , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/química , Ratos , Relação Estrutura-Atividade
8.
Toxicol Res ; 30(3): 149-57, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25343008

RESUMO

Smoking is one of the most serious but preventable causes of cardiovascular disease (CVD). Key aspects of pathological process associated with smoking include endothelial dysfunction, a prothrombotic state, inflammation, altered lipid metabolism, and hypoxia. Multiple molecular events are involved in smokinginduced CVD. However, the dysregulations of reactive oxygen species (ROS) generation and metabolism mainly contribute to the development of diverse CVDs, and NADPH oxidase (NOX) has been established as a source of ROS responsible for the pathogenesis of CVD. NOX activation and resultant ROS production by cigarette smoke (CS) treatment have been widely observed in isolated blood vessels and cultured vascular cells, including endothelial and smooth muscle cells. NOX-mediated oxidative stress has also been demonstrated in animal studies. Of the various NOX isoforms, NOX2 has been reported to mediate ROS generation by CS, but other isoforms were not tested thoroughly. Of the many CS constituents, nicotine, methyl vinyl ketone, and α,ß-unsaturated aldehydes, such as, acrolein and crotonaldehyde, appear to be primarily responsible for NOX-mediated cytotoxicity, but additional validation will be needed. Human epidemiological studies have reported relationships between polymorphisms in the CYBA gene encoding p22phox, a catalytic subunit of NOX and susceptibility to smoking-related CVDs. In particular, G allele carriers of A640G and -930(A/G) polymorphisms were found to be vulnerable to smoking-induced cardiovascular toxicity, but results for C242T studies are conflicting. On the whole, evidence implicates the etiological role of NOX in smoking-induced CVD, but the clinical relevance of NOX activation by smoking and its contribution to CVD require further validation in human studies. A detailed understanding of the role of NOX would be helpful to assess the risk of smoking to human health, to define high-risk subgroups, and to develop strategies to prevent or treat smoking-induced CVD.

10.
J Med Chem ; 57(4): 1543-56, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24472025

RESUMO

The protein-protein interaction (PPI) between menin and mixed lineage leukemia (MLL) plays a critical role in acute leukemias, and inhibition of this interaction represents a new potential therapeutic strategy for MLL leukemias. We report development of a novel class of small-molecule inhibitors of the menin-MLL interaction, the hydroxy- and aminomethylpiperidine compounds, which originated from HTS of ∼288000 small molecules. We determined menin-inhibitor co-crystal structures and found that these compounds closely mimic all key interactions of MLL with menin. Extensive crystallography studies combined with structure-based design were applied for optimization of these compounds, resulting in MIV-6R, which inhibits the menin-MLL interaction with IC50 = 56 nM. Treatment with MIV-6 demonstrated strong and selective effects in MLL leukemia cells, validating specific mechanism of action. Our studies provide novel and attractive scaffold as a new potential therapeutic approach for MLL leukemias and demonstrate an example of PPI amenable to inhibition by small molecules.


Assuntos
Proteína de Leucina Linfoide-Mieloide/metabolismo , Bibliotecas de Moléculas Pequenas , Calorimetria , Cristalografia por Raios X , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Piperidinas/química , Ligação Proteica , Espectrometria de Massas por Ionização por Electrospray
11.
Leuk Lymphoma ; 52(6): 1085-97, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21417826

RESUMO

Multiple myeloma (MM) is an incurable plasma cell malignancy where nearly all patients succumb to a relapse. The current preclinical models of MM target the plasma cells, constituting the bulk of the tumor, leaving the cancer stem cells to trigger a relapse. Utilizing a three-dimensional tissue culture system where cells were grown in extracellular matrix designed to reconstruct human bone marrow, we tested the anti-multiple myeloma cancer stem cell (MM-CSC) potential of two natural product inhibitors of nuclear factor κB (NFκB). Here we show that parthenolide and andrographolide are potent anti-MM-CSC agents. Both natural products demonstrated preferential toxicity toward MM-CSCs over non-tumorigenic MM cells. Addition of the bone marrow stromal compartment abrogated andrographolide activity while having no effect on parthenolide cytoxicity. This is the first report of a natural product with anti-CSC activity in myeloma, suggesting that it has the potential to improve the survival of patients with MM by eliminating the relapse-causing MM-CSCs.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Sesquiterpenos/farmacologia , Andrographis/química , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , NF-kappa B/antagonistas & inibidores , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Tanacetum parthenium/química
12.
Toxicol In Vitro ; 25(1): 177-84, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21040777

RESUMO

To evaluate the anti-apoptotic effects of Joongpoongtang 05 (JP05), a mixture of plant extracts, on a Neuro-2a (N2a) cell model of oxygen and glucose deprivation (OGD)/reperfusion (OGDR), a neuroblastoma cell injury model was induced by OGDR. This model allowed us to investigate cerebral ischemic changes and the protective effects of JP05. JP05 treatment significantly enhanced cell viability and reduced the levels of lactate dehydrogenase, nitric oxide, reactive oxygen species and the oxidants/antioxidants balance in neuronal cells as compared to the untreated OGDR group. Here, JP05 reduced OGDR-induced expressions of heme oxygenase-1 and nitric oxide synthase, which may contribute to the neuroprotection. JP05 also partially reversed the effects of OGDR on NF-κB and activated Akt production. Our findings suggest that JP05 confers neuroprotective effects via anti-apoptotic property against OGDR-induced free radical injury in N2a cells.


Assuntos
Apoptose/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Medicina Tradicional Coreana , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Oxirredução/efeitos dos fármacos , Fitoterapia , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
J Org Chem ; 74(18): 7176-9, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19697954

RESUMO

The palladium-catalyzed arylation of different alpha-methylene-gamma-lactone-containing sesquiterpene lactones was shown to produce E-olefin coupling products selectively in moderate to excellent yields. Biological evaluation of these semisynthetic sesquiterpene lactone derivatives in HeLa cells showed interesting antiproliferative profiles and provided initial structure-activity data.


Assuntos
Antineoplásicos , Lactonas/química , Paládio/química , Sesquiterpenos , Alcenos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Catálise , Células HeLa/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Lactonas/síntese química , Lactonas/farmacologia , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade
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