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1.
Clin Transl Oncol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251495

RESUMO

BACKGROUND: Neoadjuvant immunochemotherapy (NICT) is a new treatment method for resectable non-small-cell lung cancer (NSCLC). Network meta-analysis assessed efficacy, safety, and optimal treatment. METHODS: We searched for randomized controlled trials (RCTs) comparing NICT with neoadjuvant chemotherapy (NCT) in PubMed, Embase, Web of Science, Cochrane Library, and international conferences. Outcomes were surgical resection rate, pathological complete response(pCR),event-free survival (EFS), and Grade 3-5 treatment-related adverse events (TRAEs). RESULTS: RCTs of 3,387 patients, six treatment combinations, and two modalities were included. Meta-analysis showed that NICT yielded higher pCR and EFS rates than NCT. The toripalimab-chemotherapy combination had the highest surgical resection rate (OR = 1.68, 95% CI: 1.05-2.73), pCR (OR = 38.84, 95% CI: 11.05-268.19) and EFS (HR = 0.40, 95% CI: 0.28-0.58).This regimen worked well for patients with low programmed death-ligand 1 (PD-L1) expression or squamous cell pathology. For high PD-L1 expression and patients with NSCLC, neoadjuvant nivolumab with chemotherapy had the most efficacy. The incidence of treatment-related adverse events increased with longer treatment cycles, with perioperative nivolumab combined with chemotherapy showing the worst safety profile (RR = 1.32, 95% CI: 1.00-1.76), while neoadjuvant nivolumab combined with chemotherapy alone had the best safety profile (RR = 0.91, 95% CI: 0.68-1.21). Indirect comparison showed no survival benefit for neoadjuvant-adjuvant immunotherapy (HR = 0.93, 95% CI: 0.65-1.35). In the indirect comparison between the two immune checkpoint inhibitors(ICIs), although there was no significant difference in EFS (HR = 0.81, 95% CI: 0.61-1.08), PD-1 inhibitors may still be the most effective treatment option. CONCLUSIONS: NICT effectively and safely treats resectable NSCLC. The optimal treatment combination is typically toripalimab and chemotherapy. Treatment based on PD-L1 expression and pathological type is recommended.

2.
Biomolecules ; 11(7)2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201418

RESUMO

Allosteric modulators have emerged with many potential pharmacological advantages as they do not compete the binding of agonist or antagonist to the orthosteric sites but ultimately affect downstream signaling. To identify allosteric modulators targeting an extra-helical binding site of the glucagon-like peptide-1 receptor (GLP-1R) within the membrane environment, the following two computational approaches were applied: structure-based virtual screening with consideration of lipid contacts and ligand-based virtual screening with the maintenance of specific allosteric pocket residue interactions. Verified by radiolabeled ligand binding and cAMP accumulation experiments, two negative allosteric modulators and seven positive allosteric modulators were discovered using structure-based and ligand-based virtual screening methods, respectively. The computational approach presented here could possibly be used to discover allosteric modulators of other G protein-coupled receptors.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Receptor do Peptídeo Semelhante ao Glucagon 1/química , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Sítio Alostérico/efeitos dos fármacos , Sítio Alostérico/fisiologia , Animais , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Células CHO , Cricetinae , Cricetulus , Glucagon/administração & dosagem , Glucagon/química , Glucagon/metabolismo , Humanos , Ligantes , Simulação de Acoplamento Molecular/métodos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
5.
Elife ; 82019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31855179

RESUMO

Class A G-protein-coupled receptors (GPCRs) influence virtually every aspect of human physiology. Understanding receptor activation mechanism is critical for discovering novel therapeutics since about one-third of all marketed drugs target members of this family. GPCR activation is an allosteric process that couples agonist binding to G-protein recruitment, with the hallmark outward movement of transmembrane helix 6 (TM6). However, what leads to TM6 movement and the key residue level changes of this movement remain less well understood. Here, we report a framework to quantify conformational changes. By analyzing the conformational changes in 234 structures from 45 class A GPCRs, we discovered a common GPCR activation pathway comprising of 34 residue pairs and 35 residues. The pathway unifies previous findings into a common activation mechanism and strings together the scattered key motifs such as CWxP, DRY, Na+ pocket, NPxxY and PIF, thereby directly linking the bottom of ligand-binding pocket with G-protein coupling region. Site-directed mutagenesis experiments support this proposition and reveal that rational mutations of residues in this pathway can be used to obtain receptors that are constitutively active or inactive. The common activation pathway provides the mechanistic interpretation of constitutively activating, inactivating and disease mutations. As a module responsible for activation, the common pathway allows for decoupling of the evolution of the ligand binding site and G-protein-binding region. Such an architecture might have facilitated GPCRs to emerge as a highly successful family of proteins for signal transduction in nature.


Assuntos
Motivos de Aminoácidos/genética , Ligação Proteica/genética , Conformação Proteica , Receptores Acoplados a Proteínas G/química , Regulação Alostérica/genética , Sítios de Ligação/genética , Humanos , Ligantes , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/genética
6.
Acta Pharmacol Sin ; 40(9): 1245-1255, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31138898

RESUMO

Chemical genomics has been applied extensively to evaluate small molecules that modulate biological processes in Saccharomyces cerevisiae. Here, we use yeast as a surrogate system for studying compounds that are active against metazoan targets. Large-scale chemical-genetic profiling of thousands of synthetic and natural compounds from the Chinese National Compound Library identified those with high-confidence bioprocess target predictions. To discover compounds that have the potential to function like therapeutic agents with known targets, we also analyzed a reference library of approved drugs. Previously uncharacterized compounds with chemical-genetic profiles resembling existing drugs that modulate autophagy and Wnt/ß-catenin signal transduction were further examined in mammalian cells, and new modulators with specific modes of action were validated. This analysis exploits yeast as a general platform for predicting compound bioactivity in mammalian cells.


Assuntos
Autofagia/efeitos dos fármacos , Descoberta de Drogas , Saccharomyces cerevisiae/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Correlação de Dados , Perfil Genético , Genômica/métodos , Células HEK293 , Células HeLa , Humanos , Estudo de Prova de Conceito , beta Catenina/metabolismo
7.
J Appl Clin Med Phys ; 19(5): 609-615, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30058257

RESUMO

PURPOSE: The purpose of this study was to study the influence of the minimum segment width (MSW) on volumetric modulated arc therapy (VMAT) plan quality, delivery accuracy, and efficiency for cervical cancer treatment. METHODS: Nineteen patients with cervical cancer were randomly selected to design VMAT plans. Three VMAT plans were generated for each patient incorporating MSWs of 0.5, 1.0, and 1.5 cm while other planning parameters remained constant using the Monaco treatment planning system (TPS) with 6 MV X rays delivered from an Elekta Synergy linear accelerator. Plan quality and delivery efficiency were evaluated based on dose-volume histograms (DVHs), control points, monitor units (MUs), dosimetric measurement verification results, and plan delivery time. RESULTS: Except for the small difference in target dose coverage and maximum dose, there were no statistically significant differences between the other dosimetric parameters in the planning target volumes. The 1.0 and 1.5 cm MSW plans showed lower maximum doses to the spinal cord than the 0.5 cm plan; doses to other organs at risks were similar regardless of MSWs. The mean reductions of total MUs when compared with the 0.5 cm plan were 14.5 ± 6.1% and 20.9 ± 7.9% for MSWs of 1.0 and 1.5 cm, respectively. The calculated gamma indices using the 3% and 3 mm criteria were 96.2 ± 0.6%, 97.0 ± 0.6%, and 97.6 ± 0.6% for the 0.5, 1.0 and 1.5 cm MSW plans, respectively. The plan delivery times decreased with increasing MSWs (p < 0.05). CONCLUSION: Increasing the MSW allows for improved plan delivery accuracy and efficiency without significantly affecting the VMAT plan quality. MSWs of 1.0 and 1.5 cm improved the plan quality, delivery accuracy, and efficiency for cervical VMAT radiation therapy.


Assuntos
Neoplasias do Colo do Útero , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada
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