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1.
Cancer Sci ; 115(3): 734-751, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38233340

RESUMO

The morbidity of colorectal cancer (CRC) has risen to third place among malignant tumors worldwide. In addition, CRC is a common cancer in China whose incidence increases annually. Angiogenesis plays an important role in the development of tumors because it can bring the nutrients that cancer cells need and take away metabolic waste. Various mechanisms are involved in the formation of neovascularization, and vascular endothelial growth factor is a key mediator. Meanwhile, angiogenesis inhibitors and drug resistance (DR) are challenges to consider when formulating treatment strategies for patients with different conditions. Thus, this review will discuss the molecules, signaling pathways, microenvironment, treatment, and DR of angiogenesis in CRC.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Transdução de Sinais , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/farmacologia , China , Neovascularização Patológica/patologia , Microambiente Tumoral
2.
Nanotechnology ; 33(38)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35705025

RESUMO

Carbon quantum dots are widely used in various fields owing to excellent optical properties and outstanding biocompatibility. We synthesize rare super body-centered cubic (C8) structured carbon quantum dots by using cheap source materials and simple preparation method. They exhibit one shifting blue emission band and two close immobile green bands. They have large Stokes shifts ranging from 0.68 to 1.01 eV and large quantum yields as high as 60%. The three types of emissions are competitive and their intensities vary sensitively and differently with pH. Moreover, their emission intensity versus excitation power curves followI(P)∝Pkwithkvalues significantly smaller than unity. The blue emission follows the stretched exponential decay law with an intermediate lifetime of ∼3.9 ns and a lifetime-dispersion factor of ∼0.85 whereas the two green emissions exhibit faster and slower decays with respective lifetimes of around 2.0 and 13.0 ns. The results reveal that the blue emission originates from an ensemble of emission sites exhibiting quantum confinement-like effect and two green emissions stem from pH-sensitive surface functional groups-associated fluorophores.

3.
J Chem Phys ; 156(17): 174705, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525669

RESUMO

The semiconductor-metal heteronanocrystals (HNCs) that possess a perfect epitaxial interface can accommodate novel and interesting physical phenomena owing to the strong interaction and coupling between the semiconductor excitons and metal plasmons at the interface. Here, we fabricate the pyramidal ZnO-Au HNCs and study their unique photophysical properties. Several Au nanospheres are perfectly epitaxially bound with a single ZnO NC owing to the small lattice mismatch between them and there are also ZnO-Au-ZnO sandwiched HNCs. There is a strong coupling between the green defect-associated recombination in the ZnO NC and the localized surface plasmon resonance (LSPR) of the Au nanosphere at the interface of the HNC. This leads to resonant defect recombination-LSPR energy transfer and resultant nearly complete quenching of the green defect luminescence of the ZnO NCs in the HNCs, leaving only the UV exciton luminescence. The lifetimes of both the green and UV emission bands decrease significantly in the ZnO-Au HNCs relative to that of the pure ZnO NCs owing to the combined effect of resonance energy transfer and surface plasmon enhanced radiative transition. The exponent of the luminescence intensity-excitation intensity power function for the green emission band is remarkably smaller than unity, and this suggests that the involved defects have an intermediate concentration.

4.
Angew Chem Int Ed Engl ; 61(34): e202206953, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35705783

RESUMO

The natural product, BE-43547A2 , decreases pancreatic cancer cell stemness. However, its anticancer molecular mechanisms have not been fully established. Based on structure-activity relationships of BE-43547A2 , we synthesized a probe and investigated its potential targets using an in situ click reaction. We found that BE-43547A2 exerts its anticancer effects by covalently binding the cysteine234 (C234) residue of eukaryotic translation elongation factor 1 alpha 1 (eEF1A1). This binding mode was confirmed by a series of experiments including a xenograft mouse model. We also determined that eEF1A1 plays an important role in regulating pancreatic cancer cell stemness. Analyses of 99 clinical pancreatic cancer samples revealed that eEF1A1 expressions are closely correlated with clinicopathological grade and patient survival. In conclusion, eEF1A1 is involved in pancreatic cancer progression and is therefore, a promising novel covalent target for pancreatic cancer treatment.


Assuntos
Neoplasias Pancreáticas , Fator 1 de Elongação de Peptídeos , Animais , Antineoplásicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Química Click , Humanos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fator 1 de Elongação de Peptídeos/química , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Cell Mol Med ; 25(12): 5707-5720, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34002930

RESUMO

To investigate the therapeutic effects of phellodendrine in ulcerative colitis (UC) through the AMPK/mTOR pathway. Volunteers were recruited to observe the therapeutic effects of Compound Cortex Phellodendri Liquid (Huangbai liniment). The main components of Compound Cortex Phellodendri Liquid were analysed via network pharmacology. The target of phellodendrine was further analysed. Caco-2 cells were cultured, and H2 O2 was used to stimulate in vitro cell model. Expression levels of LC3, AMPK, p-AMPK, mTOR and p-mTOR were detected via Western blotting and through immunofluorescence experiments. The therapeutic effects of phellodendrine were analysed via expression spectrum chip sequencing. The sequencing of intestinal flora further elucidated the therapeutic effects of phellodendrine. Compared with the control group, Compound Cortex Phellodendri Liquid could substantially improve the healing of intestinal mucosa. Network pharmacology analysis revealed that phellodendrine is the main component of Compound Cortex Phellodendri Liquid. Moreover, this alkaloid targets the AMPK signalling pathway. Results of animal experiments showed that phellodendrine could reduce the intestinal damage of UC compared with the model group. Findings of cell experiments indicated that phellodendrine treatment could activate the p-AMPK /mTOR signalling pathway, as well as autophagy. Expression spectrum chip sequencing showed that treatment with phellodendrine could promote mucosal healing and reduce inflammatory responses. Results of intestinal flora detection demonstrated that treatment with phellodendrine could increase the abundance of flora and the content of beneficial bacteria. Phellodendrine may promote autophagy by regulating the AMPK-mTOR signalling pathway, thereby reducing intestinal injury due to UC.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Colite Ulcerativa/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Quinolizinas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Adulto , Animais , Estudos de Casos e Controles , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Serina-Treonina Quinases TOR/genética
6.
Nanotechnology ; 31(50): 505712, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33021232

RESUMO

Nanodiamonds are popular biological labels because of their superior mechanical and optical properties. Their surfaces bridging the core and surrounding medium play a key role in determining their bio-linkage and photophysical properties. n-diamond is a mysterious carbon allotrope whose crystal structure remains debated. We study the influence of the crystallization temperature on the fluorescence properties of the colloidal n-diamond quantum dots (n-DQDs) with sizes of several nanometers. They exhibit multiband fluorescence across the whole visible region which depends sensitively on the crystallization temperature. Their surfaces turn from hydrophobic ones rich of sp2-bonded carbon into hydrophilic ones rich of carboxyl derivatives and hydroxyl groups as the crystallization temperature increases. The different surface states correlated with the surface structures account for the distinct fluorescence properties of the n-DQDs crystallized at different temperatures. These high-purity ultrasmall n-DQDs with tunable surface chemistry and fluorescence properties are promising multicolor biomarkers and lighting sources.

7.
J Transl Med ; 17(1): 129, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30995921

RESUMO

BACKGROUND: Glioma accounts for a large proportion of cancer, and an effective treatment for this disease is still lacking because of the absence of specific driver molecules. Current challenges in the treatment of glioma are the accurate and timely diagnosis of brain glioma and targeted treatment plans. To investigate the diagnostic biomarkers and prospective role of miRNAs in the tumorigenesis and progression of glioma, we analyzed the expression of miRNAs and key genes in glioma based on The Cancer Genome Atlas database. METHODS: Of the 701 cases that were downloaded, five were normal and 696 were glioma. Then, 1626 differentially expressed genes were identified, and 173 aberrantly expressed miRNAs were calculated by edgeR. GO and KEGG pathway enrichment analyses were performed using Cytoscape software. A coexpression network was built by weighted correlation network analysis (WGCNA). A cell scratch test and transwell, cell apoptosis and cell cycle assays were performed to validate the function of hsa-let-7b-5p. RESULTS: Based on crosstalk genes in the KEGG, PPI network, and WGCNA analyses, PLK1, CCNA2, cyclin B2 (CCNB2), and AURKA were screened as candidate diagnostic marker genes. The survival analysis revealed that high mRNA expression of PLK1, CCNA2, and AURKA was significantly associated with poor overall survival. Furthermore, hsa-let-7b-5p was identified as a core miRNA in the regulation of candidate genes involved in glioma development. We confirmed that hsa-let-7b-5p could inhibit the migration, invasion, and cell cycle of glioma cells. CONCLUSIONS: This study provides four potential biomarkers for the diagnosis of glioma, offers a potential explanation of its pathogenesis, and proposes hsa-let-7b-5p as a therapeutic target.


Assuntos
Biologia Computacional , Glioma/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , MicroRNAs/metabolismo , Invasividade Neoplásica , Mapas de Interação de Proteínas/genética , Reprodutibilidade dos Testes , Regulação para Cima/genética
9.
Theranostics ; 10(19): 8790-8806, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754278

RESUMO

Background and Purpose: The role of the cartilage oligomeric matrix protein (COMP) in epithelial-mesenchymal transition (EMT) in tumor progression has been studied, but its exact regulatory mechanism remains unknown. Methods: The interaction between COMP and the actin-binding protein transgelin (TAGLN) was identified by interaction protein prediction and co-immunoprecipitation and verified through the stochastic optical reconstruction microscopy (STORM) and duolink experiments. Western blot and immunofluorescence analyses were conducted to detect the changes in EMT-related markers after COMP overexpression and knockdown. Molecular docking and Biacore of the interaction interface of COMP/TAGLN revealed that Chrysin directly targeted COMP. The promotion of COMP and the Chrysin inhibition of EMT were detected through the cell migration, invasion, apoptosis, and xenotransplantation of nude mice. Results: COMP interacts with TAGLN in EMT in colorectal cancer to regulate cytoskeletal remodeling and promote malignant progression. COMP is highly expressed in highly malignant colorectal cancer and positively correlated with TAGLN expression. COMP knockdown can inhibit colorectal cancer metastasis and invasion, whereas COMP overexpression promotes EMT in colorectal cancer. Through virtual screening of the protein interaction interface, Chrysin, a flavonoid compound extracted from Oroxylum indicum, was found to have the highest docking score to the COMP/TAGLN complex. Chrysin inhibited COMP, thereby preventing EMT and the malignant progression of colorectal cancer. Conclusions: This study illustrated the role of COMP in EMT and suggested that COMP/TAGLN may be a potential tumor therapeutic target. Chrysin exhibits obvious antitumor effects. This work provides a preliminary antitumor therapy to target COMP or its interaction protein to inhibit EMT.


Assuntos
Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavonoides/farmacologia , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Animais , Proteína de Matriz Oligomérica de Cartilagem/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos , Proteínas dos Microfilamentos/química , Simulação de Acoplamento Molecular , Proteínas Musculares/química , Transplante de Neoplasias , Ligação Proteica/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
10.
Cell Death Dis ; 10(10): 757, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591377

RESUMO

PAI-1 plays significant roles in cancer occurrence, relapse and multidrug resistance and is highly expressed in tumours. ACT001, which is currently in phase I clinical trials for the treatment of glioblastoma (GBM). However, the detailed molecular mechanism of ACT001 is still unclear. In this study, we investigated the effects of ACT001 on glioma cell proliferation and clarified its mechanism. We discovered that PAI-1 was the direct target of ACT001 by a cellular thermal shift assay. Then, the interaction between ACT001 and PAI-1 was verified by Biacore assays, thermal stability assays and ACT001 probe assays. Furthermore, from the proteomic analysis, we found that ACT001 directly binds PAI-1 to inhibit the PI3K/AKT pathway, which induces the inhibition of glioma cell proliferation, invasion and migration. Moreover, the combination of ACT001 and cisplatin showed a synergistic effect on the inhibition of glioma in vitro and in vivo. In conclusion, our findings demonstrate that PAI-1 is a new target of ACT001, the inhibition of PAI-1 induces glioma inhibition, and ACT001 has a synergistic effect with cisplatin through the inhibition of the PAI-1/PI3K/AKT pathway.


Assuntos
Cisplatino/farmacologia , Glioma/tratamento farmacológico , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Glioma/genética , Glioma/patologia , Humanos , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Fosfatidilinositol 3-Quinases/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Proteômica , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Artigo em Inglês | MEDLINE | ID: mdl-30423524

RESUMO

This study investigated pharmacokinetics, tissue distribution and excretion of ACT001 in Sprague-Dawley rats. Stability study and metabolism study of ACT001 are conducted. The absolute bioavailability of ACT001 is 50.82%. ACT001 has no accumulation effect and displayed wide tissue distribution. ACT001 can be rapidly distributed to tissues after oral administration and can diffuse through the blood-brain barrier. The total cumulative excretion of ACT001 in feces, urine and bile were found to be 0.05, 3.42 and 0.012%, respectively. UPLC/ESI-QTOF-MS coupled with MetaboLynx XS software was utilized to detect the metabolites of ACT001 in vitro. Five metabolites (M1, M2, M3, M4 and M5) were detected. M2 wasn't discovered in human liver microsome samples and bile samples. M1 and M2 weren't discovered in rat plasma and human plasma. M3, M4 and M5 weren't discovered in bile samples. M5 is an active metabolite named micheliolide (MCL). There is no significant difference in half-life, type of identified metabolites and the amount of each metabolites between using rat plasma and human plasma. Owing to the species differences of hepatomicrosome enzymes, significant differences were shown in half-life, type of identified metabolites and the amount of each metabolites between using rat liver microsome and human liver microsome.


Assuntos
Sesquiterpenos de Guaiano/metabolismo , Sesquiterpenos de Guaiano/farmacocinética , Administração Oral , Animais , Estabilidade de Medicamentos , Limite de Detecção , Modelos Lineares , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sesquiterpenos de Guaiano/administração & dosagem , Sesquiterpenos de Guaiano/química , Distribuição Tecidual
12.
Talanta ; 161: 278-287, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769407

RESUMO

The bioanalysis and especially the sample preparation of nucleoside drugs in complex media, such as human plasma, has been challenging due to the high polarity and high solubility of these drugs in water. Online solid phase extraction (SPE) offers significant advantages, such as automation and timesaving. Thus, several types of SPE columns have been developed for compounds with different polarities. In this study, SPE was applied to overcome the issue of sample pretreatment of nucleoside drugs in human plasma, with the final aim of establishing a robust analytical platform for drugs with similar structures. A simple, easy-to-use, and efficient method is described for the simultaneous determination of lamivudine, zidovudine, didanosine and emtricitabine in human plasma via online SPE and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Following a simple centrifugation step, a 10µL plasma sample was injected directly onto the HPLC system. The Oasis MCX cartridge was washed, and the analytes were removed by back-flushing directly onto the analytical column. The analytes were quantified using a triple-quadrupole tandem mass spectrometer in multiple-reaction monitoring mode. Similarly, with the development and application of a Bond Elut phenylboronic acid (PBA) SPE cartridge, a fully automated online SPE-HPLC-MS/MS method was established for the simultaneous determination of ribavirin and taribavirin in human plasma. Linear calibration curves were obtained over the range of 0.5-2000ngmL-1, and the limit of quantification ranged from 0.5ngmL-1 to 10ngmL-1, which is sensitive enough for clinical drug monitoring. The intra- and inter-day precisions were in the range of 0.2-8.9%, and the trueness ranged between 88.9% and 113.1%. Excellent recoveries from plasma were achieved with a range between 86.7% and 105.1%. This procedure is easier to perform and requires less sample handling compared to methods previously described in the literature. This high-throughput method involving the direct injection of plasma samples may provide a practical solution for the analysis of multiple nucleoside drugs in clinical research. The method was tested in plasma samples from some patients and showed good performance.


Assuntos
Nucleosídeos/sangue , Cromatografia Líquida , Humanos , Inositol/análogos & derivados , Inositol/sangue , Metronidazol/sangue , Sistemas On-Line , Extração em Fase Sólida , Espectrometria de Massas em Tandem
13.
J Med Chem ; 58(17): 7007-20, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26226279

RESUMO

Inspired by the biosynthesis of sesquiterpene lactones (SLs), herein we report the asymmetric total synthesis of the germacrane ring (24). The synthetic strategy features a selective aldol reaction between ß,γ-unsaturated chiral sulfonylamide 15a and aldehyde 13, as well as the intramolecular α-alkylation of sulfone 21 to construct a 10-membered carbocylic ring. The key intermediate 24 can be used to prepare the natural products costunolide and parthenolide (PTL), which are the key precursors for transformation into other SLs. Furthermore, the described synthetic sequences are amenable to the total synthesis of SL analogues, such as trifluoromethylated analogues 32 and 45. Analogues 32 and 45 maintained high activities against a series of cancer cell lines compared to their parent PTL and costunolide, respectively. In addition, 32 showed enhanced tolerance to acidic media compared with PTL. To our surprise, PTL and 32 showed comparable half-lives in rat plasma and in the presence of human liver microsomes.


Assuntos
Antineoplásicos/química , Sesquiterpenos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Flúor , Meia-Vida , Halogenação , Humanos , Microssomos Hepáticos/metabolismo , Ratos , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
14.
Eur J Pharm Sci ; 44(1-2): 127-35, 2011 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-21742030

RESUMO

To enhance oral bioavailability and anti-diabetic efficacy of berberine (BER), an anhydrous reverse micelle (ARM) delivery system was prepared through lyophilization of water-in-oil (W/O) emulsions. Using soy phosphatidylcholine as emulsifiers, BER-containing W/O emulsions were prepared and then lyophilized to form dry products which, upon addition of oil, formed clear ARMs containing amorphous BER nanoparticles. BER-loaded ARMs or free BER solutions were administered to streptozocin-induced diabetic mice. In vivo measurements demonstrated that the blood glucose levels (BGLs) of diabetic mice reduced on average to 22% of the initial values 4h after intravenous injection of BER solution at the dose of 2.5mg/kg body weight, while the average BGL reduction was 57% in the group gavaged with ARMs at the dose of 100mg/kg body weight. No significant BGL reduction was noticed in mice orally received BER solutions. Compared to BER solutions, the oral bioavailability of BER-loaded ARMs was enhanced 2.4-fold, and the maximum blood concentration of BER was enhanced 2.1-fold with a 2-h time lag leading to a prolonged efficacy. Thus, this novel ARM delivery system provides a valid method to improve oral bioavailability and anti-diabetic efficacy of BER, offering a promising product alternative to other hypoglycemic drugs for diabetes therapy.


Assuntos
Berberina/uso terapêutico , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Hipoglicemiantes/uso terapêutico , Mucosa Bucal/metabolismo , Nanopartículas/química , Administração Oral , Animais , Berberina/administração & dosagem , Berberina/farmacocinética , Disponibilidade Biológica , Glicemia/análise , Cristalização , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Emulsões , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Luz , Masculino , Camundongos , Camundongos Endogâmicos , Micelas , Microscopia Eletrônica de Varredura , Estrutura Molecular , Tamanho da Partícula , Espalhamento de Radiação , Solubilidade , Estreptozocina/farmacologia , Propriedades de Superfície
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