Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Intervirology ; 64(3): 147-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951637

RESUMO

BACKGROUND: Enterovirus 71 (EV71) infects millions of children every year in China and has become a challenge to public health. However, there is no effective treatment for EV71 infection. Long noncoding RNAs (lncRNAs) have been found to play various roles in virus replication and infection. OBJECTIVE: We aimed to explore the role of a novel long noncoding RNA AK097647 (lncRNA-AK097647) during EV71 infection. METHODS: To assess the role of lncRNA-AK097647 during EV71 infection, siRNAs were used to silence lncRNA-K097647 expression. RT-qPCR assay and Western blotting were applied to measure the mRNA and protein levels of EV71 VP1 and the phosphorylation of NF-κB. ELISA was used to detect the level of IFN-λ1 expression. RESULTS: The novel lncRNA-AK097647 was upregulated in human rhabdomyosarcoma cells and the blood of hand, foot, and mouth disease patients infected with EV71, as demonstrated by RT-qPCR. Interestingly, RNAi-mediated knockdown of lncRNA-AK097647 dramatically increased the level of IFN-λ1 expression, resulting in the suppression of EV71 replication. In contrast, overexpression of lncRNA-AK097647 decreased the level of IFN-λ1 expression and resulted in increased EV71 replication. In addition, we found that lncRNA-AK097647 could inhibit the phosphorylation of NF-κB. CONCLUSION: These results suggest a novel mechanism by which EV71 evades the IFN-mediated host antiviral response by increasing lncRNA-AK097647 expression.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , RNA Longo não Codificante , Enterovirus Humano A/genética , Infecções por Enterovirus/genética , Humanos , RNA Longo não Codificante/genética , Regulação para Cima , Replicação Viral
2.
Biomark Res ; 8: 18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32514351

RESUMO

Chimeric antigen receptor (CAR) T cell therapy, especially anti-CD19 CAR T cell therapy, has shown remarkable anticancer activity in patients with relapsed/refractory acute lymphoblastic leukemia, demonstrating an inspiring complete remission rate. However, with extension of the follow-up period, the limitations of this therapy have gradually emerged. Patients are at a high risk of early relapse after achieving complete remission. Although there are many studies with a primary focus on the mechanisms underlying CD19- relapse related to immune escape, early CD19+ relapse owing to poor in vivo persistence and impaired efficacy accounts for a larger proportion of the high relapse rate. However, the mechanisms underlying CD19+ relapse are still poorly understood. Herein, we discuss factors that could become obstacles to improved persistence and efficacy of CAR T cells during production, preinfusion processing, and in vivo interactions in detail. Furthermore, we propose potential strategies to overcome these barriers to achieve a reduced CD19+ relapse rate and produce prolonged survival in patients after CAR T cell therapy.

3.
Front Immunol ; 10: 2664, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798590

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is highly effective in the treatment of B-cell acute lymphoblastic leukemia (ALL) or B-cell lymphoma, providing alternative therapeutic options for patients who failed to respond to conventional treatment or relapse. Moreover, it can bridge other therapeutic strategies and greatly improve patient prognosis, with broad applicable prospects. Even so, 30-60% patients relapse after treatment, probably due to persistence of CAR T-cells and escape or downregulation of CD19 antigen, which is a great challenge for disease control. Therefore, understanding the mechanisms that underlie post-CAR relapse and establishing corresponding prevention and treatment strategies is important. Herein, we discuss post-CAR relapse from the aspects of CD19-positive and CD19-negative and provide some reasonable prevention and treatment strategies.


Assuntos
Antígenos CD19/imunologia , Imunoterapia Adotiva/métodos , Recidiva Local de Neoplasia/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos Quiméricos/uso terapêutico , Humanos , Receptores de Antígenos Quiméricos/imunologia
4.
Virol Sin ; 31(2): 131-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27060091

RESUMO

Coxsackievirus A16 (CVA16) is one of major pathogens of hand, foot and mouth disease (HFMD) in children. Long non-coding RNAs (IncRNAs) have been implicated in various biological processes, but they have not been associated with CVA16 infection. In this study, we comprehensively characterized the landscape of IncRNAs of normal and CVA16 infected rhabdomyosarcoma (RD) cells using RNA-Seq to investigate the functional relevance of IncRNAs. We showed that a total of 760 IncRNAs were upregulated and 1210 IncRNAs were downregulated. Out of these dysregulated IncRNAs, 43.64% were intergenic, 22.31% were sense, 15.89% were intronic, 8.67% were bidirectional, 5.59% were antisense, 3.85% were sRNA host IncRNAs and 0.05% were enhancer. Six dysregulated IncRNAs were validated by quantitative PCR assays and the secondary structures of these IncRNAs were projected. Moreover, we conducted a bioinformatics analysis of an IncRNAs (ENST00000602478) to elucidate the diversity of modification and functions of IncRNAs. In summary, the current study compared the dysregulated IncRNAs profile upon CVA16 challenge and illustrated the intricate relationship between coding and IncRNAs transcripts. These results may not only provide a complete picture of transcription in CVA16 infected cells but also provide novel molecular targets for treatments of HFMD.


Assuntos
Infecções por Coxsackievirus/virologia , Enterovirus/genética , Enterovirus/metabolismo , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , Sequência de Bases , Linhagem Celular , Regulação Viral da Expressão Gênica , Doença de Mão, Pé e Boca/virologia , Humanos , Técnicas de Diagnóstico Molecular/métodos , RNA Longo não Codificante/química , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Rabdomiossarcoma/virologia
5.
Oncotarget ; 7(8): 9222-35, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26824182

RESUMO

Abnormalities of autophagy have been implicated in an increasing number of human cancers, including glioma. To date, there is a wealth of evidence indicating that microRNAs (miRNAs) contribute significantly to autophagy in a variety of cancers. Previous studies have suggested that miR-129 functioned as an important inhibitor of the cell cycle and could promote the apoptosis of many cancer cell lines in vitro. Here, we reported that miR-129 acted as a potent inducer of autophagy. Forced expression of miR-129 could induce autophagic flux by targetedly suppressing Notch-1 in glioma cells. The autophagy induced by miR-129 could restrain the activity of mammalian target of rapamycin (mTOR) and upregulate Beclin-1. Moreover, we demonstrated that E2F transcription factor 7 (E2F7) could also trigger autophagic flux by upregulating Beclin-1 and mediating miR-129-induced autophagy. Additionally, knockdown of Notch-1 could upregulate the expression of E2F7, whereas downregulation of E2F7 alleviated shNotch-1-induced autophagic flux. In particular, knockdown of endogenous Beclin-1 could effectively reduce autophagic flux stimulated by miR-129 and E2F7. Interestingly, upon attenuation of miR-129- or E2F7-triggered autophagic flux rescued cell viability suppressed by them. More importantly, intratumoral injection of pHAGE-miR-129 lentivirus in a nude mouse xenograft model significantly restrained tumor growth and triggered autophagy. In conclusion, these findings identify a new function for miR-129 as a potent inducer of autophagy through a novel Notch-1/E2F7/Beclin-1 axis in glioma.


Assuntos
Autofagia/genética , Proteína Beclina-1/metabolismo , Fator de Transcrição E2F7/metabolismo , Glioma/genética , MicroRNAs/genética , Receptor Notch1/metabolismo , Animais , Proteína Beclina-1/genética , Linhagem Celular , Glioma/patologia , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Interferência de RNA , RNA Interferente Pequeno/genética , Receptor Notch1/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Transplante Heterólogo , Regulação para Cima
6.
PLoS One ; 10(4): e0122109, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25853521

RESUMO

Autophagy is an important homeostatic process for the degradation of cytosolic proteins and organelles and has been reported to play an important role in cellular responses to pathogens and virus replication. However, the role of autophagy in Coxsackievirus A16 (CA16) infection and pathogenesis remains unknown. Here, we demonstrated that CA16 infection enhanced autophagosome formation, resulting in increased extracellular virus production. Moreover, expression of CA16 nonstructural proteins 2C and 3C was sufficient to trigger autophagosome accumulation by blocking the fusion of autophagosomes with lysosomes. Interestingly, we found that Immunity-related GTPase family M (IRGM) was crucial for the activation of CA16 infection-induced autophagy; in turn, reducing IRGM expression suppressed autophagy. Expression of viral protein 2C enhanced IRGM promoter activation, thereby increasing IRGM expression and inducing autophagy. CA16 infection inhibited Akt/mTOR signaling and activated extracellular signal-regulated kinase (ERK) signaling, both of which are necessary for autophagy induction. In summary, CA16 can use autophagy to enhance its own replication. These results raise the possibility of targeting the autophagic pathway for the treatment of hand, foot, and mouth disease (HFMD).


Assuntos
Autofagia/genética , Proteínas de Transporte/genética , Infecções por Coxsackievirus/genética , Enterovirus/genética , Proteínas de Ligação ao GTP/biossíntese , Proteínas não Estruturais Virais/genética , Proteínas de Transporte/biossíntese , Infecções por Coxsackievirus/virologia , Enterovirus/patogenicidade , Proteínas de Ligação ao GTP/genética , Regulação Viral da Expressão Gênica , Células HeLa , Humanos , Lisossomos/genética , Sistema de Sinalização das MAP Quinases/genética , Serina-Treonina Quinases TOR/genética , Proteínas não Estruturais Virais/biossíntese , Replicação Viral/genética
7.
Int J Oncol ; 47(4): 1603-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26323558

RESUMO

Treatment with cisplatin, a chemotherapeutic agent commonly used in glioma patients, often results in chemoresistance. Increasing evidence has shown that microRNAs (miRNAs) are implicated in the drug resistance of gliomas. However, the function of miR­873 in cisplatin resistance of gliomas remains unknown. In this study, we found that many miRNAs, including miR­873, are differentially expressed in cisplatin-resistant glioma cells compared to wild-type glioma cells. Moreover, cisplatin reduced the expression of miR­873 in a time-dependent manner. Overexpression of miR­873 decreased the cell proliferation, migration and invasion while increased apoptosis of cisplatin-resistant glioma cells and sensitized the cells to cisplatin-induced cell growth arrest and apoptosis. Furthermore, miR­873 was downregulated while Bcl-2 was upregulated in the tissues of twelve high-grade glioma patients compared to seven normal brain tissues, and the miR­873 level was negatively correlated with the Bcl-2 protein level. A luciferase reporter assay further confirmed that Bcl-2 was a direct target of miR­873, and miR­873 decreased the level of the Bcl-2 protein in cisplatin-resistant glioma cells. Notably, re-expression of Bcl-2 attenuated the function of miR­873 in cisplatin-resistant glioma cells and the sensitivity of the cells to cisplatin. Taken together, these data suggest that miR­873 might be a potential marker for cisplatin resistance and a promising sensitizer in cisplatin treatment.


Assuntos
Neoplasias Encefálicas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioma/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Antineoplásicos/farmacologia , Western Blotting , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Cisplatino/farmacologia , Glioma/patologia , Humanos , MicroRNAs , Invasividade Neoplásica/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Langmuir ; 23(5): 2322-5, 2007 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-17261038

RESUMO

Phase-contrast microscopy and particle tracking algorithms are used to study the near-surface diffusion of poly(N-isopropylacrylamide) (PNIPAAm) brush functionalized micron-sized silica microspheres after sedimentation from aqueous suspension onto planar substrates coated with a similar polymer brush above and below the lower critical solution temperature (LCST) of PNIPAAm, 32 degrees C. A small negative charge on the wall and the particles (zeta potential = -6 mV) prevents adhesion above and below the LCST. The near-surface translational diffusion coefficient (D(surface)) is compared to the bulk-phase translational diffusion coefficient (D(bulk)), which was measured by dynamic light scattering. We find that D(surface)/D(bulk) is approximately equal to 0.6 at temperatures T < 32 degrees C but rises abruptly to approximately 0.8-0.9 at T > 32 degrees C. Near-surface diffusion is expected to be slower than bulk diffusion owing to hydrodynamic coupling to the wall, implying reduced hydrodynamic coupling at the higher temperatures, perhaps mediated by enhanced electrostatic repulsion above the LCST transition.

9.
Langmuir ; 22(2): 817-23, 2006 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-16401136

RESUMO

We report the preparation and characterization of poly(N-isopropylacrylamide) (PNIPAAm) polymer brushes exhibiting controlled lateral variations in the patchiness of polymer chains. These gradients were achieved through an atom transfer radical polymerization (ATRP) grafting-from approach utilizing surfaces on which the spatial profile of the initiator density was carefully controlled. Initiator density gradients were formed on Au by first preparing a hexadecanethiol (HDT) density gradient, by reductive desorption using a laterally anisotropic electrochemical gradient. The bare areas in the original HDT gradient were then back-filled with a disulfide initiator, (BrC(CH3)2COO(CH2)11S)2. The initiator coverage was characterized by X-ray photoelectron spectroscopy (XPS). Then, surface-initiated ATRP was utilized to transfer the initiator density gradient into gradients of PNIPAAm chain density. Ellipsometry, surface plasmon resonance (SPR), and atomic force microscopy (AFM) were used to characterize these PNIPAAm density gradients. The defining characteristic of the PNIPAAm gradients is the evolution of the morphology from discontinuous mushroom structures at extremely low grafting densities to heterogeneous patchy structures at intermediate grafting densities. The size of the patchy domains gradually increases, until at a high grafting density region, the morphology evolves to a smoother, presumably more extended, structure.

11.
Langmuir ; 20(19): 8313-20, 2004 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-15350108

RESUMO

Patterned poly(N-isopropylacrylamide) (PNIPAAm) brushes were fabricated on oxidized silicon wafers by surface-initiated atom transfer radical polymerization of N-isopropylacrylamide from a micropatterned initiator. The patterned surface initiator was prepared by microcontact-printing octadecyltrichlorosilane and backfilling with 3-(aminopropyl)triethoxysilane followed by amidization with 2-bromo-2-methylpropionic acid. XPS and FTIR confirmed the chemical structure of the surface initiator and the PNIPAAm brushes. Surface analysis techniques, including ellipsometry, contact angle goniometry, and X-ray reflectometry (XRR), were used to characterize the thickness, roughness, hydrophilicity, and density of the polymer brushes. Tapping-mode AFM imaging confirmed the successful patterning of the PNIPAAm brushes on the oxidized silicon substrates. Variable temperature ellipsometry indicated that the lower critical solution temperature of the hydrated PNIPAAm brush was broad, occurring over the range of 20-35 degrees C. A solvatochromic fluorophore, 6-propionyl-2-dimethylaminonaphthalene (Prodan), in the PNIPAAm brush layers yielded a very similar emission to that in DMF, which can be attributed to the similarity of their chemical structures. Fluorescence microscopy further proved the successful patterning of the polymer brushes and suggested that the Prodan is localized in the patterned PNIPAAm brushes and excluded from the surrounding octadecyltrichlorosilane regions.


Assuntos
Resinas Acrílicas/síntese química , Dióxido de Silício/química , Resinas Acrílicas/química , Microscopia de Força Atômica/métodos , Tamanho da Partícula , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos , Espectrometria por Raios X/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA