Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
J Agric Food Chem ; 72(25): 14141-14151, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864686

RESUMO

The cotton aphid, Aphis gossypii, is a polyphagous pest that stunts host plant growth via direct feeding or transmitting plant virus. Due to the long-term application of insecticides, A. gossypii has developed different levels of resistance to numerous insecticides. We found that five field populations had evolved multiple resistances to neonicotinoids. To explore the resistance mechanism mediated by uridine diphosphate glycosyltransferases (UGTs), two upregulated UGT genes in these five strains, UGT350C3 and UGT344L7, were selected for functional analysis of their roles in neonicotinoid detoxification. Transgenic Drosophila bioassay results indicated that compared with the control lines, the UGT350C3 and UGT344L7 overexpression lines were more tolerant to thiamethoxam, imidacloprid, and dinotefuran. Knockdown of UGT350C3 and UGT344L7 significantly increased A. gossypii sensitivity to thiamethoxam, imidacloprid, and dinotefuran. Molecular docking analysis demonstrated that these neonicotinoids could bind to the active pockets of UGT350C3 and UGT344L7. This study provides functional evidence of neonicotinoid detoxification mediated by UGTs and will facilitate further work to identify strategies for preventing the development of neonicotinoid resistance in insects.


Assuntos
Afídeos , Glicosiltransferases , Resistência a Inseticidas , Inseticidas , Neonicotinoides , Nitrocompostos , Animais , Afídeos/genética , Afídeos/enzimologia , Afídeos/efeitos dos fármacos , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Neonicotinoides/química , Inseticidas/farmacologia , Inseticidas/química , Inseticidas/metabolismo , Resistência a Inseticidas/genética , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Glicosiltransferases/química , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Tiametoxam , Drosophila/genética , Drosophila/enzimologia , Drosophila/efeitos dos fármacos , Drosophila/metabolismo , Guanidinas
2.
BMC Cancer ; 24(1): 321, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454345

RESUMO

BACKGROUND: Definitive concurrent chemoradiotherapy (dCCRT) is the gold standard for the treatment of locally advanced esophageal squamous cell carcinoma (ESCC). However, the potential benefits of consolidation chemotherapy after dCCRT in patients with esophageal cancer remain debatable. Prospective randomized controlled trials comparing the outcomes of dCCRT with or without consolidation chemotherapy in patients with ESCC are lacking. In this study, we aim to generate evidence regarding consolidation chemotherapy efficacy in patients with locally advanced, inoperable ESCC. METHODS: This is a multicenter, prospective, open-label, phase-III randomized controlled trial comparing non-inferiority of dCCRT alone to consolidation chemotherapy following dCCRT. In total, 600 patients will be enrolled and randomly assigned in a 1:1 ratio to receive either consolidation chemotherapy after dCCRT (Arm A) or dCCRT alone (Arm B). Overall survival will be the primary endpoint, whereas progression-free survival, locoregional progression-free survival, distant metastasis-free survival, and treatment-related toxicity will be the secondary endpoints. DISCUSSION: This study aid in further understanding the effects of consolidation chemotherapy after dCCRT in patients with locally advanced, inoperable ESCC. TRIAL REGISTRATION: ChiCTR1800017646.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Quimioterapia de Consolidação , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como Assunto , Estudos de Equivalência como Asunto
3.
J Agric Food Chem ; 72(7): 3406-3414, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329423

RESUMO

The expression of P450 genes is regulated by trans-regulatory factors or cis-regulatory elements and influences how endogenous or xenobiotic substances are metabolized in an organism's tissues. In this study, we showed that overexpression of the cytochrome P450 gene, CYP6CY22, led to resistance to cyantraniliprole in Aphis gossypii. The expression of CYP6CY22 increased in the midgut and remaining carcass of the CyR strain, and after repressing the expression of CYP6CY22, the mortality of cotton aphids increased 2.08-fold after exposure to cyantraniliprole. Drosophila ectopically expressing CYP6CY22 exhibited tolerance to cyantraniliprole and cross-tolerance to xanthotoxin, quercetin, 2-tridecanone, tannic acid, and nicotine. Moreover, transcription factor CF2-II (XM_027994540.2) is transcribed only as the splicing variant isoform CF2-II-AS, which was found to be 504 nucleotides shorter than CF2-II in A. gossypii. RNAi and yeast one-hybrid (Y1H) results indicated that CF2-II-AS positively regulates CYP6CY22 and binds to cis-acting element p (-851/-842) of CYP6CY22 to regulate its overexpression. The above results indicated that CYP6CY22 was regulated by the splicing isoform CF2-II-AS, which will help us further understand the mechanism of transcriptional adaption of cross-tolerance between synthetic insecticides and plant secondary metabolites mediated by P450s.


Assuntos
Afídeos , Inseticidas , Polifenóis , Pirazóis , ortoaminobenzoatos , Animais , Processamento Alternativo , Afídeos/genética , Afídeos/metabolismo , Xenobióticos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Isoformas de Proteínas/genética , Inseticidas/farmacologia , Inseticidas/metabolismo , Resistência a Inseticidas/genética
5.
Elife ; 112022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35333177

RESUMO

The ATP binding cassette (ABC) transporter of mitochondria (Atm) from Arabidopsis thaliana (AtAtm3) has been implicated in the maturation of cytosolic iron-sulfur proteins and heavy metal detoxification, plausibly by exporting glutathione derivatives. Using single-particle cryo-electron microscopy, we have determined four structures of AtAtm3 in three different conformational states: two inward-facing conformations (with and without bound oxidized glutathione [GSSG]), together with closed and outward-facing states stabilized by MgADP-VO4. These structures not only provide a structural framework for defining the alternating access transport cycle, but also reveal the paucity of cysteine residues in the glutathione binding site that could potentially form inhibitory mixed disulfides with GSSG. Despite extensive efforts, we were unable to prepare the ternary complex of AtAtm3 containing both GSSG and MgATP. A survey of structurally characterized type IV ABC transporters that includes AtAtm3 establishes that while nucleotides are found associated with all conformational states, they are effectively required to stabilize occluded, closed, and outward-facing conformations. In contrast, transport substrates have only been observed associated with inward-facing conformations. The absence of structures with dimerized nucleotide binding domains containing both nucleotide and transport substrate suggests that this form of the ternary complex exists only transiently during the transport cycle.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Arabidopsis , Transportadores de Cassetes de Ligação de ATP/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Arabidopsis/metabolismo , Sítios de Ligação , Microscopia Crioeletrônica , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Conformação Proteica
6.
Elife ; 112022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982029

RESUMO

Nicotinic partial agonists provide an accepted aid for smoking cessation and thus contribute to decreasing tobacco-related disease. Improved drugs constitute a continued area of study. However, there remains no reductionist method to examine the cellular and subcellular pharmacokinetic properties of these compounds in living cells. Here, we developed new intensity-based drug-sensing fluorescent reporters (iDrugSnFRs) for the nicotinic partial agonists dianicline, cytisine, and two cytisine derivatives - 10-fluorocytisine and 9-bromo-10-ethylcytisine. We report the first atomic-scale structures of liganded periplasmic binding protein-based biosensors, accelerating development of iDrugSnFRs and also explaining the activation mechanism. The nicotinic iDrugSnFRs detect their drug partners in solution, as well as at the plasma membrane (PM) and in the endoplasmic reticulum (ER) of cell lines and mouse hippocampal neurons. At the PM, the speed of solution changes limits the growth and decay rates of the fluorescence response in almost all cases. In contrast, we found that rates of membrane crossing differ among these nicotinic drugs by >30-fold. The new nicotinic iDrugSnFRs provide insight into the real-time pharmacokinetic properties of nicotinic agonists and provide a methodology whereby iDrugSnFRs can inform both pharmaceutical neuroscience and addiction neuroscience.


Assuntos
Alcaloides/química , Azepinas/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Agonistas Nicotínicos/química , Abandono do Hábito de Fumar , Alcaloides/metabolismo , Animais , Azocinas/química , Azocinas/metabolismo , Fluorescência , Humanos , Ligantes , Camundongos , Quinolizinas/química , Quinolizinas/metabolismo
7.
Protein Sci ; 31(3): 752-757, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34878193

RESUMO

We report the steady state ATPase activities of the ATP Binding Cassette (ABC) exporter NaAtm1 in the absence and presence of a transported substrate, oxidized glutathione (GSSG), in detergent, nanodiscs, and proteoliposomes. The steady state kinetic data were fit to the "nonessential activator model" where the basal ATPase rate of the transporter is stimulated by GSSG. The detailed kinetic parameters varied between the different reconstitution conditions, highlighting the importance of the lipid environment for NaAtm1 function. The increased ATPase rates in the presence of GSSG more than compensate for the modest negative cooperativity observed between MgATP and GSSG in lipid environments. These studies highlight the central role of the elusive ternary complex in accelerating the ATPase rate that is at the heart of coupling mechanism between substrate transport and ATP hydrolysis.


Assuntos
Adenosina Trifosfatases , Trifosfato de Adenosina , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Glutationa , Hidrólise , Cinética
8.
Cancer Gene Ther ; 28(12): 1312-1324, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33531648

RESUMO

Gastric cancer is the third leading cause of cancer-related death worldwide, with relapse and metastasis being major contributors to the mortality. Circular RNAs (circRNAs) have been at the center of several researches and some circRNAs have been indicated to be involved in gastric cancer as sponges. Nevertheless, the mechanism underlying the function of circRNA remains largely unclear. Therefore, this study was conducted with the main objective of screening the associated circRNA in gastric cancer and exploring its mechanism. Expression of hsa_circRNA_0009172 was validated in gastric cancer tissues and cell lines after the correlation between hsa_circRNA_0009172 and prognosis was determined. Moreover, the binding site between miR-485-3p and hsa_circRNA_0009172 or NTRK3 was verified using dual luciferase assay and RNA pull down. Function-gain and -loss experiments were performed for the purpose of detecting the effect of hsa_circRNA_0009172 in vivo and in vitro as well as its mechanism with microRNA (miRNA)-485-3p and NTRK3 in gastric cancer. The hsa_circRNA_0009172 expression was downregulated in gastric cancer tissues and cell lines, indicating a positive association with patient prognosis. Functionally, hsa_circ_0009172 overexpression inhibited proliferative, invasive and migrative potential of gastric cancer cells as well as epithelial-mesenchymal transition (EMT)-related proteins by sponging miR-485-3p to inhibit NTRK3, while miR-485-3p overexpression could reverse the inhibitory effect of hsa_circ_0009172 on gastric cancer. Furthermore, either up-regulation of hsa_circ_0009172 or down-regulation of miR-485-3p led to the suppression of xenograft tumor growth in nude mice. In conclusion, hsa_circ_0009172 serves as a tumor suppressor in gastric cancer by targeting miR-485-3p/NTRK3 axis.


Assuntos
RNA Circular/metabolismo , Receptor trkC/metabolismo , Neoplasias Gástricas/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Camundongos , Camundongos Nus , Neoplasias Gástricas/patologia , Transfecção
9.
Thorac Cancer ; 12(6): 899-905, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33529496

RESUMO

BACKGROUND: Stereotactic ablative radiotherapy (SABR) is the current standard-of-care in cases of inoperable early stage non-small cell lung cancer (ES-NSCLC). This study aimed to assess the survival outcomes and recurrence patterns after SABR for ES-NSCLC in a hospital setting. METHODS: A single-institution retrospective study was performed which included 109 patients who had undergone SABR. The main study endpoints were overall survival (OS), cancer specific survival (CSS), local recurrence-free survival (LRFS), regional recurrence free survival (RRFS) and distant metastasis-free survival (DMFS). Univariate and multivariate analysis were conducted to explore the potential factors which might be related to patient survival. RESULTS: A total of 109 patients were enrolled into the study. Median follow-up was 44 months (range: 2-93 months). (i) Recurrence results: Among 45 patients with recurrence, 30 patients (28%) had distant metastasis (DM), 17 patients (16%) had local recurrence (LR), 10 patients (9%) had regional recurrence (RR) of lymph nodes and two patients (2%) had second primary lung cancer (SPLC). (ii) Survival results: Median OS, CSS, PFS was 78 months, 78 and 40 months. Two-year OS, CSS, PFS, LRFS, RRFS and DMFS was 84.7%, 87.1%, 69.2%, 86.8%, 92.7% and 78.0%, respectively. Four-year OS, CSS, PFS, LRFS, RRFS and DMFS was 55.6%, 60.7%, 37.3%, 76.3%, 88.4% and 59.4%, respectively. (iii) Univariate and multivariate analyses indicated that age was a prognostic factor of CSS in patients aged <75 years (P = 0.04 HR 2.12 95% confidence interval [CI]: 1.04-4.33). CONCLUSIONS: Although high survival rates can be achieved in ES-NSCLC patients treated with SABR, using SABR on its own may not be enough. Prolonged surveillance and adjuvant therapy is therefore needed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento
10.
Acta Crystallogr F Struct Biol Commun ; 76(Pt 9): 398-405, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32880587

RESUMO

During the crystal structure analysis of an ATP-binding cassette (ABC) transporter overexpressed in Escherichia coli, a contaminant protein was crystallized. The identity of the contaminant was revealed by mass spectrometry to be the Escherichia coli transcription terminator factor Rho, structures of which had been previously determined in different conformational states. Although Rho was present at only ∼1% of the target protein (a bacterial homolog of the eukaryotic ABC transporter of mitochondria from Novosphingobium aromaticivorans; NaAtm1), it preferentially crystallized in space group C2 as thin plates that diffracted to 3.30 Šresolution. The structure of Rho in this crystal form exhibits a hexameric open-ring staircase conformation with bound ATP; this characteristic structure was also observed on electron-microscopy grids of the NaAtm1 preparation.


Assuntos
Transportadores de Cassetes de Ligação de ATP/ultraestrutura , Artefatos , Cristalografia por Raios X/normas , Proteínas de Escherichia coli/ultraestrutura , Escherichia coli/genética , Sphingomonadaceae/genética , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Microscopia Crioeletrônica , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expressão Gênica , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Sphingomonadaceae/metabolismo , Transgenes
11.
Proc Natl Acad Sci U S A ; 117(32): 19228-19236, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32703810

RESUMO

The ATP-binding cassette (ABC) transporter of mitochondria (Atm1) mediates iron homeostasis in eukaryotes, while the prokaryotic homolog from Novosphingobium aromaticivorans (NaAtm1) can export glutathione derivatives and confer protection against heavy-metal toxicity. To establish the structural framework underlying the NaAtm1 transport mechanism, we determined eight structures by X-ray crystallography and single-particle cryo-electron microscopy in distinct conformational states, stabilized by individual disulfide crosslinks and nucleotides. As NaAtm1 progresses through the transport cycle, conformational changes in transmembrane helix 6 (TM6) alter the glutathione-binding site and the associated substrate-binding cavity. Significantly, kinking of TM6 in the post-ATP hydrolysis state stabilized by MgADPVO4 eliminates this cavity, precluding uptake of glutathione derivatives. The presence of this cavity during the transition from the inward-facing to outward-facing conformational states, and its absence in the reverse direction, thereby provide an elegant and conceptually simple mechanism for enforcing the export directionality of transport by NaAtm1. One of the disulfide crosslinked NaAtm1 variants characterized in this work retains significant glutathione transport activity, suggesting that ATP hydrolysis and substrate transport by Atm1 may involve a limited set of conformational states with minimal separation of the nucleotide-binding domains in the inward-facing conformation.


Assuntos
Transportadores de Cassetes de Ligação de ATP/química , Proteínas de Bactérias/química , Sphingomonadaceae/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Glutationa/química , Glutationa/metabolismo , Ferro/metabolismo , Domínios Proteicos , Sphingomonadaceae/química , Sphingomonadaceae/genética
12.
BMC Cancer ; 20(1): 303, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293362

RESUMO

BACKGROUND: Neoadjuvant therapy plus oesophagectomy has been accepted as the standard treatment for patients with potentially curable locally advanced oesophageal cancer. No completed randomized controlled trial (RCT) has directly compared neoadjuvant chemotherapy and neoadjuvant chemoradiation in patients with oesophageal squamous cell carcinoma (ESCC). The aim of the current RCT is to investigate the impact of neoadjuvant chemotherapy plus surgery and neoadjuvant chemoradiotherapy plus surgery on overall survival for patients with resectable locally advanced ESCC. METHODS: This open label, single-centre, phase III RCT randomized patients (cT2-T4aN + M0 and cT3-4aN0M0) in a 1:1 fashion to receive either the CROSS regimen (paclitaxel 50 mg/m2; carboplatin (area under the curve = 2), q1w, 5 cycles; and concurrent radiotherapy, 41.4 Gy/23 F, over 5 weeks) or neoadjuvant chemotherapy (paclitaxel 175 mg/m2; and cisplatin 75 mg/m2, q21d, 2 cycles). Assuming a 12% 5-year overall survival difference in favour of the CROSS regimen, 80% power with a two-sided alpha level of 0.05 and a 5% dropout each year for an estimated 3 years enrolment, the power calculation requires 456 patients to be recruited (228 in each group). The primary endpoint is 5-year overall survival, with a minimum 5-year follow-up. The secondary endpoints include 5-year disease-free survival, toxicity, pathological complete response rate, postoperative complications, postoperative mortality and quality of life. A biobank of pre-treatment and resected tumour tissue will be built for translational research in the future. DISCUSSION: This RCT directly compares a neoadjuvant chemotherapy regimen with a standard CROSS regimen in terms of overall survival for patients with locally advanced ESCC. The results of this RCT will provide an answer for the controversy regarding the survival benefits between the two treatment strategies. TRIAL REGISTRATION: NCT04138212, date of registration: October 24, 2019.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimiorradioterapia/métodos , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Esofagectomia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Fracionamento da Dose de Radiação , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Masculino , Terapia Neoadjuvante , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Projetos de Pesquisa , Análise de Sobrevida , Resultado do Tratamento
13.
Fitoterapia ; 143: 104590, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32272164

RESUMO

The acquired resistance to gefitinib limits its clinical application. Epigallocatechin-3-gallate (EGCG) has been found to enhance the efficacy of gefitinib against resistant. However, the cellular and molecular mechanisms have not been completely illuminated in NSCLC. In this study, a new epigallocatechin gallate derivative (2R,3R-6-methoxycarbonylgallocatechin-3-O-gallate, the following referred to as EGCGD) (1) and three known epigallocatechin gallate compounds including epicatechin-3-O-gallate (2), gallocatechin-3-O-gallate (3) and epigallocatechin-3-O-gallate (4, EGCG) were isolated and identified from Anhua dark tea. The pharmacological studies showed EGCGD was more effective against gefitinib-resistant HCC827-Gef cells compared to that of other three epigallocatechin gallate compounds including EGCG, suggesting that introduction of 6-methoxycarbonyl to EGCG might enhance its antitumor activities. Further study on molecular mechanism showed EGCGD increased the potency of gefitinib against HCC827-Gef cells via suppression of epithelial-Mesenchymal transition (EMT) and dual inhibition of PI3K/mTOR.


Assuntos
Catequina/análogos & derivados , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Gefitinibe/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Chá/química , Apoptose , Catequina/isolamento & purificação , Catequina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , China , Sinergismo Farmacológico , Humanos , Estrutura Molecular , Fosfatidilinositol 3-Quinases , Inibidores de Fosfoinositídeo-3 Quinase/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
14.
Eur J Med Chem ; 190: 112108, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058239

RESUMO

Aurora A kinase, a member of the Aurora kinase family, is frequently overexpressed in various human cancers. In addition, Overexpression of Aurora A kinase is associated with drug resistance and poor prognosis in many cancers including breast cancer. Therefore, Aurora A kinase has been considered as an attractive anticancer target for the treatment of human cancers. Herein, A series of 6-(2-amino-1H-benzo[d]imidazole-6-yl)quinazolin-4(3H)-one derivatives were designed, synthesized, and evaluated as Aurora A kinase inhibitors. The cell-based cytotoxicity assays showed that compound 16h was the most potent cytotoxic agent against all tested cancer cells and had a lower IC50 value than ENMD-2076 against MDA-MB-231 cells. Meanwhile, Aurora A kinase assay and Western blot analysis showed that 16h inhibited Aurora A kinase with an IC50 value of 21.94 nM and suppressed the phosphorylation of Histone H3 on Ser10 and Aurora A kinase on Thr288, which were consistent with the activation of Aurora A kinase. Accordingly, 16h caused aberrant mitotic phenotypes and obvious G2/M phase arrest in MDA-MB-231 cells and induced caspase-dependent apoptosis in MDA-MB-231 cells. These results demonstrated that 16h is a potential candidate for the development of anticancer agents targeting Aurora A kinase.


Assuntos
Antineoplásicos/farmacologia , Aurora Quinase A/antagonistas & inibidores , Benzimidazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Aurora Quinase A/metabolismo , Benzimidazóis/síntese química , Benzimidazóis/metabolismo , Domínio Catalítico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Quinazolinonas/síntese química , Quinazolinonas/metabolismo
15.
Sci Rep ; 10(1): 1735, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015469

RESUMO

The role of definitive radiotherapy (dRT) and debulking surgery (DS) for patients with locally advanced, unresectable, Masaoka-Koga stage III thymomas was not well studied. Unresectable tumor refers to tumor that could not be completely resected because of invasion of surrounding organs. Consecutive patients with unresectable stage III thymomas between 2000 and 2017 were reviewed. According to the treatment intent and radiation dose, patients were categorized into a dRT group and a non-dRT group. The former group included patients who received radiotherapy at doses ≥ 54 Gy after DS or biopsy. The latter group included patients who did not receive radiotherapy and those who received a radiation dose < 54 Gy. A total of 82 patients were included. Compared with non-dRT, dRT significantly improved 5-year overall survival (OS, P = 0.003), progression-free survival (PFS, P = 0.008), and freedom from locoregional failure (FFLF, P < 0.001). Compared with biopsy alone, DS did not improve OS, PFS, FFLF. On multivariate analysis, dRT was an independent prognostic factor for OS (hazard ratio [HR]: 2.37, P = 0.024), PFS (HR: 2.40, P = 0.004), and FFLF (HR: 3.83, P = 0.001). In conclusion, dRT was an effective and beneficial treatment for patients with unresectable Masaoka-Koga stage III thymoma.


Assuntos
Procedimentos Cirúrgicos de Citorredução , Radioterapia , Timoma/terapia , Neoplasias do Timo/terapia , Adulto , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Timoma/diagnóstico , Timoma/mortalidade , Neoplasias do Timo/diagnóstico , Neoplasias do Timo/mortalidade , Resultado do Tratamento
16.
Thorac Cancer ; 10(10): 1913-1918, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31389159

RESUMO

BACKGROUND: Growing evidence indicates that several inflammatory biomarkers may predict survival in patients with malignant tumors. The aim of this study was to evaluate the prognostic value of pretreatment biomarkers in patients with primary small-cell carcinoma of the esophagus (PSCCE). METHODS: A total of 73 PSCCE patients enrolled between January 2009 and December 2017 at the Affiliated Cancer Hospital of Zhengzhou University. The total lymphocyte counts (TLC), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) prior to anticancer therapy were collected as inflammation biomarkers. The cutoff value was determined by Receiver operating characteristic (ROC). The Kaplan-Meier method was utilized to analyze overall survival (OS). Cox proportional hazards regression was used to identify univariate and multivariate prognostic factors. RESULTS: Univariate analysis showed that high NLR group (hazard ratio [HR] = 1.685; 95% CI: 1.001-2.838; P = 0.047) and high PLR group (hazard ratio [HR] = 1.716; 95% CI: 1.039-2.834; P = 0.033) were associated with poor OS, and TLC was not correlated with OS. On multivariate analysis, high PLR (hazard ratio [HR] = 1.751; 95% CI: 1.042-2.945; P = 0.035) was an independent prognostic factor of unfavorable OS. CONCLUSIONS: Pretreatment PLR and NLR are correlated with OS. These biomarkers are easily accessible, cost effective, and can serve as a marker to identify high-risk patients for further designing personalized treatment and predicting treatment outcomes.


Assuntos
Biomarcadores , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/mortalidade , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Mediadores da Inflamação/metabolismo , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Pequenas/terapia , Terapia Combinada , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Estadiamento de Neoplasias , Neutrófilos , Contagem de Plaquetas , Prognóstico , Resultado do Tratamento
17.
Fitoterapia ; 137: 104240, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201887

RESUMO

Anhua dark tea known as the earliest produced Chinese dark tea, has been commercially available and famous for its unique flavor and health care effect. NMDA receptors are glutamate-coupled ion channels that critically involved in survival of neuronal cells and neurodegenerative diseases. Thus, it is considered a promising target for the therapy of neurodegenerative disease. In this study, four catechins including two new catechins derivatives (1-2), together with thirteen known flavonoids were isolated from Anhua dark tea. The structures of compounds 1-2 [2S,3R-6-methoxycarbonylgallocatechin (1) and 2R,3R-6-methoxycarbonylgallocatechin (2)] were determined on the basis of their spectroscopic data. The preliminary bioassay indicated that compound 1 showed the best neuroprotective effects via N-methyl-d-aspartate (NMDA) receptors inhibition. Compound 1 protected SH-SY5Y cells against NMDA-induced injury and cell apoptosis via the modulation of NR2B expression, the activation of PI3K/Akt signaling and caspase-dependent pathway. The results suggested compound 1 would be a potent dietary therapy reagent for prevention of excitable brain injury.


Assuntos
Catequina/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Chá/química , Apoptose , Catequina/análogos & derivados , Linhagem Celular Tumoral , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Neuroblastoma , Fármacos Neuroprotetores/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
18.
Fitoterapia ; 134: 44-49, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30763719

RESUMO

Four new ent-kaurane diterpenoid maizediterpenes A-D (1-4), along with fourteen known compounds were isolated from the roots of Zea mays (maize). Compounds 7, 15, 16 were isolated from this genus for the first time. The planar structures of the new compounds were determined by extensive analysis of their NMR and HR-ESI-MS spectra, and the absolute configurations were established on the basis of specific rotation in association with calculated ECD spectra. Compounds 2, 6 and 18 showed significant antiproliferative effects against five human cancer cell lines (A549, MDA-MB-231, SK-Hep-1, SNU638, HCT116) with IC50 values ranging from 1.99 ±â€¯0.41 µM to 15.18 ±â€¯1.17 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Zea mays/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , China , Diterpenos do Tipo Caurano/isolamento & purificação , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
19.
Fitoterapia ; 134: 81-87, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30690126

RESUMO

In this study, a new flavonolignan vernicilignan A was isolated from Toxicodendron vernicifluum. The neuroprotective effects of this compound against H2O2 induced cell injury in SH-SY5Y cells were evaluated by MTT assay and LDH release assay. Vernicilignan A dose-dependently attenuated the cell injury and LDH release induced by H2O2 in SH-SY5Y cells. Further study indicated that vernicilignan A reduced cell apoptosis caused by H2O2 treatment via regulation of some apoptotic related proteins including Bax, Bcl-2, caspase 3 and caspase 9. Also, vernicilignan A increase the cell viability of H2O2 treated cells via the activation of Akt and GSK3ß. Base on the findings, vernicilignan A exhibited neuroprotective effects through the activation of PI3K/Akt signaling and inhibition of mitochondria apoptosis pathway. Vernicilignan A might be a promising therapeutic agent for oxidative stress induced neurodegenerative diseases.


Assuntos
Flavonolignanos/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Toxicodendron/química , Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Sobrevivência Celular , China , Flavonolignanos/isolamento & purificação , Humanos , Peróxido de Hidrogênio , Mitocôndrias , Estrutura Molecular , Fármacos Neuroprotetores/isolamento & purificação , Fosfatidilinositol 3-Quinases/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Madeira/química , Proteína X Associada a bcl-2/metabolismo
20.
Cancer Biol Ther ; 19(10): 875-878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29580147

RESUMO

Advanced gastric cancer with a pathological complete response to neoadjuvant chemotherapy and surgery followed by early brain metastasis is rare. A 52-y-old male patient who was diagnosed with advanced gastric cancer (cT4N2M0, stage ШB). Radiological examinations after three cycles of preoperative chemotherapy with a modified FOLFOX6 (mFOLFOX6) regimen showed a partial response (PR) had been achieved. The patient underwent curative surgery consisting of proximal gastrectomy, and D2 lymph node dissection. The lack of abnormal gastric cancer cells in the primary lesion or lymph nodes confirmed a pathological complete response (pCR). Postoperative chemotherapy with oral S-1 was administrated. However, during the second cycles of postoperative chemotherapy, the patient experienced headaches, projectile vomiting and convulsion. Upon further examination, a tumor representing metastasis to the brain was recognized by cranial enhanced magnetic resonance imaging (MRI) examination and cytopathology of cerebrospinal fluid. In addition to documenting the case report, we reviewed the literature associated to features of metastatic brain malignancies that form from gastric cancer. In short, advanced gastric cancer patents achieved pCR after preoperative chemotherapy typically have good prognosis; however, great attention should be paid on detecting metastatic events.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Biópsia , Neoplasias Encefálicas/diagnóstico , Terapia Combinada , Gastrectomia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA