Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Cell Mol Gastroenterol Hepatol ; 13(5): 1393-1412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35093591

RESUMO

BACKGROUND & AIMS: Hepatic fibrosis is characterized by hepatic stellate cell (HSC) activation and transdifferentiation-mediated extracellular matrix (ECM) deposition, which both contribute to cirrhosis. However, no antifibrotic regimen is available in the clinic. microRNA-23b/27b/24-1 cluster inhibition of transforming growth factor-ß (TGF-ß) signaling during hepatic development prompted us to explore whether this cluster inhibits HSC activation and hepatic fibrosis. METHODS: Experimental fibrosis was studied in carbon tetrachloride (CCl4)-treated C57BL/6 mice. After administration of miR-23b/27b/24-1 lentivirus or vehicle, animals were euthanized for liver histology. In primary rat HSC and HSC-T6, the anti-fibrotic effect of miR-23b/27b/24-1 cluster was furtherly investigated by RNA-sequencing, luciferase reporter assay, western blotting and bioinformatic means. RESULTS: In this study, we showed that increasing the miR-23b/27b/24-1 level through intravenous delivery of miR-23b/27b/24-1 lentivirus ameliorated mouse hepatic fibrosis. Mechanistically, the miR-23b/27b/24-1 cluster directly targeted messenger RNAs, which reduced the protein expression of 5 secretory profibrotic genes (TGF-ß2, Gremlin1, LOX, Itgα2, and Itgα5) in HSCs. Suppression of the TGF-ß signaling pathway by down-regulation of TGF-ß2, Itgα2, and Itgα5, and activation of the bone morphogenetic protein signaling pathway by inhibition of Gremlin1, decreased extracellular matrix secretion of HSCs. Furthermore, down-regulation of LOX expression softened the ECM. Moreover, a reduction in tissue inhibitors of metalloproteinase 1 expression owing to weakened TGF-ß signaling increased ECM degradation. CONCLUSIONS: Hepatic overexpression of the miR-23b/27b/24-1 cluster blocked hepatic fibrosis and may be a novel therapeutic regimen for patients with hepatic fibrosis.


Assuntos
Células Estreladas do Fígado , MicroRNAs , Animais , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Fator de Crescimento Transformador beta2/metabolismo
2.
Cell Biochem Funct ; 38(5): 524-532, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32056246

RESUMO

G-quadruplexes form folded structures because of tandem repeats of guanine sequences in DNA or RNA. They adopt a variety of conformations, depending on many factors, including the type of loops and cations, the nucleotide strand number, and the main strand polarity of the G-quadruplex. Meanwhile, the different conformations of G-quadruplexes have certain influences on their biological functions, such as the inhibition of transcription, translation, and DNA replication. In addition, G-quadruplex binding proteins also affect the structure and function of G-quadruplexes. Some chemically synthesized G-quadruplex sequences have been shown to have biological activities. For example, bimolecular G-quadruplexes of AS1411 act as targets of exogenous drugs that inhibit the proliferation of malignant tumours. G-quadruplexes are also used as vehicles to deliver nanoparticles. Thus, it is important to identify the factors that influence G-quadruplex structures and maintain the stability of G-quadruplexes. Herein, we mainly discuss the factors influencing G-quadruplexes and the synthetic G-quadruplex, AS1411. SIGNIFICANCE OF THE STUDY: This review summarizes the factors that influence G-quadruplexes and the functions of the synthetic G-quadruplex, AS1411. It also discusses the use of G-quadruplexes for drug delivery in tumour therapy.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , DNA/efeitos dos fármacos , Oligodesoxirribonucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/síntese química , Aptâmeros de Nucleotídeos/química , Quadruplex G/efeitos dos fármacos , Humanos , Oligodesoxirribonucleotídeos/síntese química , Oligodesoxirribonucleotídeos/química
3.
J Immunother Cancer ; 8(1)2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31959726

RESUMO

BACKGROUND: Although clear cell renal cell carcinoma (ccRCC) is well known as a highly immunogenic tumor, only a small subset of patients could benefit from current immunotherapy, which might be due to the heterogeneity of immune microenvironment in ccRCC. So, it is meaningful to explore novel immunotherapy or combination therapy for improving therapeutic efficacy. HHLA2, a newly discovered B7 family member, is prevalently expressed in numerous tumors, including ccRCC. This study aimed to investigate the prognostic impact of HHLA2/PD-L1 co-expression and its relationship with tumor-infiltrating lymphocytes (TILs). METHODS: The expression levels of HHLA2, PD-L1, CD8, and CD4 in cancer tissues from cases (206 in the training cohort and 197 in the validation cohort) with surgically resectable primary ccRCC were evaluated by immunohistochemistry. RESULTS: The positive rates of HHLA2 were much higher than those of PD-L1 in ccRCC tissues. HHLA2-positive expression was significantly associated with necrosis, microvascular invasion, advanced Fuhrman nuclear, and TNM stage and indicated a shorter progression-free survival (PFS) and overall survival (OS) in both cohorts. Moreover, patients with HHLA2/PD-L1 co-expression suffered the highest risk of disease progression and death by a significant margin. Besides, HHLA2/PD-L1 co-expression was significantly associated with a high density of CD8+ and CD4+ TILs. Notably, a new immune classification, based on HHLA2/PD-L1 co-expression and TILs, successfully stratified PFS and OS, especially in patients with TILs positivity. CONCLUSIONS: The expression of HHLA2 is more frequent than PD-L1 in ccRCC. HHLA2/PD-L1 co-expression had an adverse impact on the prognoses of patients with ccRCC; this finding provides a rationale for combination immunotherapy with anti-HHLA2 and PD-L1 blockage for patients with ccRCC in the future.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma de Células Renais/genética , Imunoglobulinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
4.
Chronic Dis Transl Med ; 4(1): 18-28, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29756120

RESUMO

The objective, accurate, and standardized evaluation of tumor response to treatment is an indispensable procedure in clinical oncology. Compared to manual measurement, computer-assisted linear measurement can significantly improve the accuracy and reproducibility of tumor burden quantification. For irregular-shaped and infiltrating or diffuse tumors, which are difficult to quantify by linear measurement, computer-assisted volumetric measurement may provide a more objective and sensitive quantification to evaluate tumor response to treatment than linear measurement does. In the evaluation of tumor response to novel oncologic treatments such as targeted therapy, changes in overall tumor size do not necessarily reflect tumor response to therapy due to the presence of internal necrosis or hemorrhages. This leads to a new generation of imaging biomarkers to evaluate tumor response by using texture analysis methods, also called radiomics. Computer-assisted texture analysis technology offers a more comprehensive and in-depth imaging biomarker to evaluate tumor response. The application of computer-assisted quantitative imaging analysis techniques not only reduces the inaccuracy and improves the reliability in tumor burden quantification, but facilitates the development of more comprehensive and intelligent approaches to evaluate treatment response, and hence promotes precision imaging in the evaluation of tumor response in clinical oncology. This article summarizes the state-of-the-art technical developments and clinical applications of quantitative imaging analysis in evaluation of tumor response in clinical oncology.

5.
Int J Med Sci ; 15(2): 129-141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29333097

RESUMO

Purpose: To establish small-sized superparamagnetic polymeric micelles for magnetic resonance and fluorescent dual-modal imaging, we investigated the feasibility of MR imaging (MRI) and macrophage-targeted in vitro. Methods: A new class of superparamagnetic iron oxide nanoparticles (SPIONs) and Nile red-co-loaded mPEG-Lys3-CA4-NR/SPION polymeric micelles was synthesized to label Raw264.7 cells. The physical characteristics of the polymeric micelles were assessed, the T2 relaxation rate was calculated, and the effect of labeling on the cell viability and cytotoxicity was also determined in vitro. In addition, further evaluation of the application potential of the micelles was conducted via in vitro MRI. Results: The diameter of the mPEG-Lys3-CA4-NR/SPION polymeric micelles was 33.8 ± 5.8 nm on average. Compared with the hydrophilic SPIO, mPEG-Lys3-CA4-NR/SPION micelles increased transversely (r2), leading to a notably high r2 from 1.908 µg/mL-1S-1 up to 5.032 µg/mL-1S-1, making the mPEG-Lys3-CA4-NR/SPION micelles a highly sensitive MRI T2 contrast agent, as further demonstrated by in vitro MRI. The results of Confocal Laser Scanning Microscopy (CLSM) and Prussian blue staining of Raw264.7 after incubation with micelle-containing medium indicated that the cellular uptake efficiency is high. Conclusion: We successfully synthesized dual-modal MR and fluorescence imaging mPEG-Lys3-CA4-NR/SPION polymeric micelles with an ultra-small size and high MRI sensitivity, which were effectively and quickly uptaken into Raw 264.7 cells. mPEG-Lys3-CA4-NR/SPION polymeric micelles might become a new MR lymphography contrast agent, with high effectiveness and high MRI sensitivity.


Assuntos
Meios de Contraste/química , Macrófagos/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Micelas , Polímeros/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/farmacologia , Compostos Férricos/química , Corantes Fluorescentes/química , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/química , Camundongos , Oxazinas/química , Tamanho da Partícula , Polímeros/síntese química , Células RAW 264.7
6.
World J Gastroenterol ; 19(4): 561-8, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23382637

RESUMO

AIM: To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol (PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography (CTC). METHODS: Sixty subjects who gave informed consent were randomly assigned to study group A, study group B or the control group. On the day prior to CTC, subjects in study group A were given 20 mL 40% wt/vol barium sulfate suspension before 3 mealtimes, 60 mL 60% diatrizoate meglumine diluted in 250 mL water after supper, and 10 mg bisacodyl enteric-coated tablets 1 h before oral administration of 2 L PEG-4000 electrolyte solution. Subjects in study group B were treated identically to those in study group A, with the exception of bisacodyl which was given 1 h after oral PEG-4000. Subjects in the control group were managed using the same strategy as the subjects in study group A, but without administration of bisacodyl. Residual stool and fluid scores, the attenuation value of residual fluid, and discomfort during bowel preparation in the three groups were analyzed statistically. RESULTS: The mean scores for residual stool and fluid in study group A were lower than those in study group B, but the differences were not statistically significant. Subjects in study group A showed greater stool and fluid cleansing ability than the subjects in study group B. The mean scores for residual stool and fluid in study groups A and B were lower than those in the control group, and were significantly different. There was no significant difference in the mean attenuation value of residual fluid between study group A, study group B and the control group. The total discomfort index during bowel preparation was 46, 45 and 45 in the three groups, respectively, with no significant difference. CONCLUSION: Administration of 10 mg bisacodyl enteric-coated tablets prior to or after oral administration of 2 L PEG-4000 electrolyte solution enhances stool and fluid cleansing ability, and has no impact on the attenuation value of residual fluid or the discomfort index. The former is an excellent alternative for CTC colorectum cleansing.


Assuntos
Bisacodil/uso terapêutico , Catárticos/uso terapêutico , Colonografia Tomográfica Computadorizada , Defecação/efeitos dos fármacos , Tomografia Computadorizada Multidetectores , Polietilenoglicóis/uso terapêutico , Irrigação Terapêutica/métodos , Administração Oral , Adulto , Idoso , Bisacodil/administração & dosagem , Bisacodil/efeitos adversos , Catárticos/administração & dosagem , Catárticos/efeitos adversos , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Comprimidos com Revestimento Entérico , Resultado do Tratamento , Adulto Jovem
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(1): 109-11, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16475271

RESUMO

OBJECTIVE: The effects of N-linked oligosaccharide chains (TM), an inhibitor of N-glycosylation of proteins, on the expression of beta1 integrin and the apoptosis of glomerular mesangial cells (GMC) were observed for exploring the role of inhibitors of N-linked oligosaccharide chains in cell apoptosis, proliferation, and expression of beta1 integrin and cyclin D1, and hence finding a new approach to the synteresis of proliferative nephropathy. METHODS: Cultured rat mesangial cells were divided into 4 groups: control group, and 0.5, 1.0 and 2.0 microg/mL TM-treatment groups. The expression of beta1 integrin and apoptosis rate were measured by flow cytometry; the expression of cyclin D, was measured by immunohistochemistry, and proliferation of GMCs was measured by MTT. RESULTS: The expression of beta1 integrin and cyclin D1 were decreased notably by inhibitors of N-linked oligosaccharide chains-TM. TM increased apoptosis and decreased the proliferative abilitiy of cells, and all the effects of TM were dose-dependent. CONCLUSION: Through repressed glycosylation of glycoprotein, TM can suppress the expression of beta1, integrin, affect the adhesion of cells, and increase the apoptosis rate; at the same time, the expression of cyclin D1 and the proliferative ability of cells were decreased, and all these were dose-dependent.


Assuntos
Apoptose/efeitos dos fármacos , Integrina beta1/biossíntese , Células Mesangiais/efeitos dos fármacos , Oligossacarídeos de Cadeias Ramificadas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclina D1/biossíntese , Glicoproteínas/metabolismo , Glicosilação/efeitos dos fármacos , Imuno-Histoquímica , Células Mesangiais/citologia , Células Mesangiais/metabolismo , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA