Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Int Immunopharmacol ; 126: 111183, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37984250

RESUMO

Once an ischemic stroke occurs, reactive oxygen species (ROS) and oxidative stress degrade the tight connections between cerebral endothelial cells resulting in their damage. The expression of antioxidant genes may be enhanced, and ROS formation may be reduced following Nrf2 activation, which is associated with protection against ischemic stroke. Overexpression of spermine oxidase (Smox) in the neocortex led to increased H2O2 production. However, how Smox impacts the regulation of the blood-brain barrier (BBB) through antioxidants has not been examined yet. We conducted experiments both in the cell level and in the transient middle cerebral artery occlusion (tMCAO) model to evaluate the effect of Smox siRNA lentivirus (si-Smox) knockdown on BBB protection against ischemic stroke. Mice treated with si-Smox showed remarkably decreased BBB breakdown and reduced endothelial inflammation following stroke. The treatment with si-Smox significantly elevated the Bcl-2 to Bax ratio and decreased the production of cleaved caspase-3 in the tMCAO model. Further investigation revealed that the neuroprotective effect was the result of the antioxidant properties of si-Smox, which reduced oxidative stress and enhanced CD31+ cells in the peri-infarct cortical areas. Of significance, si-Smox activated Nrf2 in both bEnd.3 cells and tMCAO animals, and blocking Nrf2 with brusatol diminished the protective effects of si-Smox. The study findings suggest that si-Smox exerts neuroprotective effects and promotes angiogenesis by activating the Nrf2 pathway, thus decreasing oxidative stress and apoptosis caused by tMCAO. As a result, si-Smox may hold potential as a therapeutic candidate for preserving BBB integrity while treating ischemic stroke.


Assuntos
AVC Isquêmico , Fármacos Neuroprotetores , Acidente Vascular Cerebral , Animais , Camundongos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/metabolismo , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/genética , AVC Isquêmico/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo
2.
Front Oncol ; 11: 633794, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646755

RESUMO

Human papillomavirus (HPV) is a double-stranded DNA (dsDNA) virus, and its high-risk subtypes increase cancer risks. However, the mechanism of HPV infection and pathogenesis still remain unclear. Therefore, understanding the molecular mechanisms and the pathogenesis of HPV are crucial in the prevention of HPV-related cancers. In this study, we analyzed cervix squamous cell carcinoma (CESC) and head and neck carcinoma (HNSC) combined data to investigate various HPV-induced cancer common features. We showed that epidermal growth factor receptor (EGFR) was downregulated in HPV-positive (HPV+) cancer, and that HPV+ cancer patients exhibited better prognosis than HPV-negative (HPV-) cancer patients. Our study also showed that TP53 mutation rate is lower in HPV+ cancer than in HPV- cancer and that TP53 can be modulated by HPV E7 protein. However, there was no significant difference in the expression of wildtype TP53 in both groups. Subsequently, we constructed HPV-human interaction network and found that EGFR is a critical factor. From the network, we also noticed that EGFR is regulated by HPV E7 protein and hsa-miR-944. Moreover, while phosphorylated EGFR is associated with a worse prognosis, EGFR total express level is not significantly correlated with prognosis. This indicates that EGFR activation will induce a worse outcome in HPV+ cancer patients. Further enrichment analysis showed that EGFR downstream pathway and cancer relative pathway are diversely activated in HPV+ cancer and HPV- cancer. In summary, HPV E7 protein downregulates EGFR that downregulates phosphorylated EGFR and inhibit EGFR-related pathways which in turn and consequently induce better prognosis.

3.
EPMA J ; 12(4): 403-433, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34539937

RESUMO

First two decades of the twenty-first century are characterised by epidemics of non-communicable diseases such as many hundreds of millions of patients diagnosed with cardiovascular diseases and the type 2 diabetes mellitus, breast, lung, liver and prostate malignancies, neurological, sleep, mood and eye disorders, amongst others. Consequent socio-economic burden is tremendous. Unprecedented decrease in age of maladaptive individuals has been reported. The absolute majority of expanding non-communicable disorders carry a chronic character, over a couple of years progressing from reversible suboptimal health conditions to irreversible severe pathologies and cascading collateral complications. The time-frame between onset of SHS and clinical manifestation of associated disorders is the operational area for an application of reliable risk assessment tools and predictive diagnostics followed by the cost-effective targeted prevention and treatments tailored to the person. This article demonstrates advanced strategies in bio/medical sciences and healthcare focused on suboptimal health conditions in the frame-work of Predictive, Preventive and Personalised Medicine (3PM/PPPM). Potential benefits in healthcare systems and for society at large include but are not restricted to an improved life-quality of major populations and socio-economical groups, advanced professionalism of healthcare-givers and sustainable healthcare economy. Amongst others, following medical areas are proposed to strongly benefit from PPPM strategies applied to the identification and treatment of suboptimal health conditions:Stress overload associated pathologiesMale and female healthPlanned pregnanciesPeriodontal healthEye disordersInflammatory disorders, wound healing and pain management with associated complicationsMetabolic disorders and suboptimal body weightCardiovascular pathologiesCancersStroke, particularly of unknown aetiology and in young individualsSleep medicineSports medicineImproved individual outcomes under pandemic conditions such as COVID-19.

4.
Clin Lab ; 67(8)2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34383409

RESUMO

BACKGROUND: Pseudomonas aeruginosa is a Gram-negative bacteria that causes a large range of human infections such as lung infection (cystic fibrosis) and urinary tract infection. Even worse, antibiotic resistant bacteria have become a serious health care problem throughout the last decade, and there is a need for a clear approach to regulate and prevent the spread of pseudomonas aeruginosa resistance. METHODS: A complete analysis of Pseudomonas aeruginosa proteomics data showed that 25% of proteins are hypothetical proteins (HPs) whose function is not precisely defined. HP gene sequence analysis offers a framework for defining sequence-function relationships with a deeper understanding of organisms' molecular mechanisms at the system level. In the current research, we used the power of different bioinformatics tools to assign the potential roles for the HPs based on protein family association, amino acid function, motifs, and pathway analysis. RESULTS: The current findings show that 30 HPs have well-defined functions and are classified as enzymes, DNA binding, periplasmic binding protein, transport, etc. Seven HPs showed virulence characteristics that is to be expected to be essential for Pseudomonas aeruginosa and pathogenesis survival. CONCLUSIONS: This study's findings may encourage a better understanding of virulence mechanisms, drug resistance, pathogenesis, and drug discovery to treat Pseudomonas aeruginosa infections.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Humanos , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/genética , Virulência
6.
Antiviral Res ; 179: 104699, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31883926

RESUMO

Viral myocarditis caused by Coxsackievirus B (CVB) infection is a severe inflammatory disease of the myocardium, which may develop to cardiomyopathy and heart failure. No effective specific treatment is available. Our previous study demonstrated that suppression of proinflammatory caspase-1 activation effectively inhibited CVB replication. N-acetyl cysteine (NAC) is a widely used antioxidant. In this study, we found that NAC significantly alleviated the myocardial injury caused by CVB type 3 (CVB3) under in vivo condition. Importantly, NAC treatment simultaneously suppressed viral replication and inflammatory response in both myocardium and cell culture. The antiviral and anti-inflammation mechanism of NAC, while independent of its antioxidant property, relies on its inhibition on caspase-1 activation. Moreover, NAC promotes procaspase-1 degradation via ubiquitin proteasome system, which further contributes to caspase-1 down-regulation. NAC also inhibits the activity of viral proteases. Taken together, this study shows that NAC exerts potent anti-CVB and anti-inflammation effect through targeting caspase-1. Given that NAC is a clinically approved medicine, we recommend NAC as a valuable therapeutic agent for viral myocarditis caused by CVB.


Assuntos
Acetilcisteína/uso terapêutico , Antivirais/uso terapêutico , Infecções por Coxsackievirus/tratamento farmacológico , Miocardite/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Inibidores de Caspase/uso terapêutico , Infecções por Coxsackievirus/complicações , Enterovirus Humano B/efeitos dos fármacos , Enterovirus Humano B/fisiologia , Células HeLa , Humanos , Inflamação/tratamento farmacológico , Inflamação/virologia , Camundongos Endogâmicos BALB C , Miocardite/virologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Organismos Livres de Patógenos Específicos
7.
Viruses ; 11(4)2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022927

RESUMO

As the only widely used live lentiviral vaccine, the equine infectious anima virus (EIAV) attenuated vaccine was developed by in vitro passaging of a virulent strain for 121 generations. In our previous study, we observed that the attenuated vaccine was gradually selected under increased environmental pressure at the population level (termed a quasispecies). To further elucidate the potential correlation between viral quasispecies evolution and pathogenesis, a systematic study was performed by sequencing env using several methods. Some key mutations were identified within Env, and we observed that increased percentages of these mutations were accompanied by an increased passage number and attenuated virulence. Phylogenetic analysis revealed that env mutations related to the loss of virulence might have occurred evolutionarily. Among these mutations, deletion of amino acid 236 in the V4 region of Env resulted in the loss of one N-glycosylation site that was crucial for virulence. Notably, the 236-deleted sequence represented a "vaccine-specific" mutation that was also found in wild EIAVLN40 strains based on single genome amplification (SGA) analysis. Therefore, our results suggest that the EIAV attenuated vaccine may originate from a branch of quasispecies of EIAVLN40. Generally, the presented results may increase our understanding of the attenuation mechanism of the EIAV vaccine and provide more information about the evolution of other lentiviruses.


Assuntos
Evolução Molecular , Genoma Viral , Vírus da Anemia Infecciosa Equina/genética , Vírus da Anemia Infecciosa Equina/patogenicidade , Quase-Espécies , Proteínas do Envelope Viral , Animais , Anemia Infecciosa Equina/prevenção & controle , Cavalos , Mutação , Filogenia , Análise de Sequência , Deleção de Sequência , Vacinas Atenuadas , Vacinas Virais , Virulência/genética
8.
Virol Sin ; 33(4): 314-322, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29959686

RESUMO

Stress granules (SGs) are intracellular granules formed when cellular translation is blocked and have been reported to be involved in a variety of viral infections. Our previous studies revealed that SGs are involved in the coxsackievirus B (CVB) infection process, but the role of SGs in CVB infection has not been fully explored. In this study, we found that CVB type 3 (CVB3) could induce SG formation in the early phase of infection. Results showed that levels of CVB3 RNA and protein were significantly inhibited during the early stage of CVB3 infection by the elevated formation of SGs, while viral RNA and protein synthesis were significantly promoted when SG formation was blocked. Our findings suggest that SG formation is one of the early antiviral mechanisms for host cells against CVB infection.


Assuntos
Antivirais/metabolismo , Infecções por Coxsackievirus/virologia , Grânulos Citoplasmáticos/metabolismo , Enterovirus Humano B/fisiologia , Proteínas do Capsídeo/biossíntese , DNA Helicases/genética , Proteína Semelhante a ELAV 1/genética , Proteína Semelhante a ELAV 1/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Fosforilação , Proteínas de Ligação a Poli-ADP-Ribose/genética , RNA Helicases/genética , Proteínas com Motivo de Reconhecimento de RNA/genética , RNA Viral/biossíntese , Estresse Fisiológico , Antígeno-1 Intracelular de Células T/genética , Antígeno-1 Intracelular de Células T/metabolismo , Replicação Viral
9.
Oncotarget ; 9(19): 14815-14827, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29599909

RESUMO

Hepatocellular carcinoma (HCC) is one of the common cancers worldwide, especially in developing countries. Although the chronic infections of hepatitis B and C viruses have been established as the etiological factors of HCC, the mechanism for the tumorigenesis and development of HCC is still unclear. The liver-specific microRNA-122 (miR-122), an established tumor-suppressor miRNA, is often down-regulated in HCC, while the underlying mechanism is not well understood. Here we report that the AU-rich element-binding factor AUF1 suppresses the expression of Dicer1, the type III RNase that is required for microRNA maturation, leading to the inhibited biogenesis of miR-122. Overexpression of AUF1 led to the decreased expression of Dicer1 and miR-122, while the level of the miR-122 precursor (pre-miR-122) was increased. On the other hand, siRNA of AUF1 (siAUF1) increased the levels of Dicer1 mRNA and miR-122, but it reduced the abundance of pre-miR-122. Consistent with the reported data, this study demonstrated that AUF1 and Dicer1 showed opposite expression pattern in both human HCC tissues and cell lines. In addition, AUF1 inhibited the expression of Dicer1 by interacting with the 3' untranslated region (3'UTR) and coding region of DICER1 mRNA. Moreover, the knockdown of AUF1 by siRNA altered the expression of other miRNAs and promoted HCC cell death. In conclusion, AUF1 down-regulates the expression miR-122 by interacting with the 3'UTR and coding region of DICER1 mRNA and suppressing Dicer1 expression. The AUF1/Dicer1/miR-122 pathway might play a critical role in the development of HCC.

10.
Exp Biol Med (Maywood) ; 242(4): 429-435, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27798120

RESUMO

Colorectal cancer is the most common malignancy of the gastrointestinal tract. Surgical treatment combined with radiotherapy is the main treatment course for colorectal cancer; nevertheless, radio-resistance is commonly encountered during the treatment course and seriously influences the therapeutic efficacy. We tested the hypothesis that the CXCL12/CXCR4 axis is closely related to radiotherapy sensitivity in colorectal cancer cells. Here, we found that the decrease in cell viability and the increase in cell death induced by radiotherapy were attenuated by CXCL12 treatment, and the inhibition of CXCR4 promoted colorectal cancer cells to be more sensitive to radiotherapy. We also examined the critical roles of CXCL12/CXCR4 in cell survival and found that radiotherapy induced Bax expression and facilitated the activity of caspase-3 and caspase-9, which were reversed by CXCL12 treatment. Cell apoptosis was enhanced by the inhibition of CXCR4 under radiotherapy conditions. Furthermore, treatment with CXCL12 resulted in an increased expression of survivin, and the inhibitory roles of CXCL12 in radiotherapy-induced apoptosis were mitigated by survivin knockdown. These results indicate that CXCL12/CXCR4 protects colorectal cancer cells against radiotherapy via survivin, implying an important underlying mechanism of resistance to radiotherapy during colorectal cancer therapy.


Assuntos
Quimiocina CXCL12/farmacologia , Neoplasias Colorretais/radioterapia , Proteínas Inibidoras de Apoptose/genética , Tolerância a Radiação/genética , Receptores CXCR4/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quimiocina CXCL12/metabolismo , Células HCT116 , Humanos , Proteínas Inibidoras de Apoptose/biossíntese , Proteínas Inibidoras de Apoptose/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Tolerância a Radiação/fisiologia , Receptores CXCR4/metabolismo , Survivina , Proteína X Associada a bcl-2/biossíntese
11.
Oncotarget ; 7(48): 79605-79616, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27793004

RESUMO

Lin28A and Lin28B are highly conserved RNA binding proteins with similar structure and functions. Recent studies demonstrated that both of them act as oncogenes and promote cancer progression. However, few researches compared the expression and functions of both oncogenes in human malignant tumors at same time. Additionally, although the expression and role of Lin28B in colon cancer is frequently reported, the expression and functions of Lin28A in colon cancer are largely unknown. In this study, we have systematically evaluated the expressional pattern, mutation status and correlation of both Lin28A and Lin28B in colon cancer tissues for the first time, and compared the roles of Lin28A and Lin28B in the proliferation, migration, invasion and apoptosis of colon cancer cells in vitro. We have showed that they are co-expressed and have functional similarities, however, the molecular mechanisms underlying their similar functions may not be identical. This study contributes to clarify the similarities and differences of Lin28A and Lin28B in colon cancer progression.


Assuntos
Neoplasias do Colo/metabolismo , Proteínas de Ligação a RNA/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Movimento Celular , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Progressão da Doença , Relação Dose-Resposta a Droga , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Ligação a RNA/genética , Transdução de Sinais , Transfecção
12.
Oncotarget ; 7(22): 32433-48, 2016 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-27074572

RESUMO

There is growing evidence of dysregulated long non-coding RNAs (lncRNAs) serving as potential biomarkers for cancer prognosis. However, systematic efforts of searching for an expression-based lncRNA signature for prognosis prediction in ovarian cancer (OvCa) have not been made yet. Here, we performed comprehensive analysis for lncRNA expression profiles and clinical data of 544 OvCa patients from The Cancer Genome Atlas (TCGA), and identified an eight-lncRNA signature with ability to classify patients of the training cohort into high-risk group showing poor outcome and low-risk group showing significantly improved outcome, which was further validated in the validation cohort and entire TCGA cohort. Multivariate Cox regression analysis and stratified analysis demonstrated that the prognostic value of this signature was independent of other clinicopathological factors. Associating the outcome prediction with BRCA1 and/or BRCA2 mutation revealed a superior prognosis performance both in BRCA1/2-mutated and BRCA1/2 wild-type tumors. Finally, a significantly correlation was found between the lncRNA signature and the complete response rate of chemotherapy, suggesting that this eight-lncRNA signature may be a measure to predict chemotherapy response and identify platinum-resistant patients who might benefit from other more efficacious therapies. With further prospective validation, this eight-lncRNA signature may have important implications for outcome prediction and therapy decisions.


Assuntos
Neoplasias Ovarianas/genética , RNA Longo não Codificante/biossíntese , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Prognóstico , RNA Longo não Codificante/metabolismo , Resultado do Tratamento
13.
Exp Mol Pathol ; 100(2): 294-302, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26896649

RESUMO

While investigating the inhibitory effect of S-allylmercaptocysteine (SAMC), a garlic derivative, on ovarian cancer, we subjected three ovarian cancer cell lines, HO8910, HO8910PM, and SKOV3, to SAMC treatment. In vivo and in vitro experiments showed that only HO8910 and SKOV3 cells were highly sensitive to SAMC, whereas HO8910PM cells were resistant to SAMC. Subsequently, we examined the apoptosis-related genes in the three cell lines. We found that survivin gene was highly expressed in HO8910PM cells. Down regulation of survivin gene in HO8910PM cells with small interference RNA (siRNA), resulted in increased sensitivity to SAMC together with a decrease in invasiveness of tumor cells. We therefore concluded that the S-allylmercaptocysteine suppresses both the proliferation and distant metastasis of epithelial ovarian cancer cells, insensitivity of HO8910PM cells to SAMC was closely related to the high level of survivin expression and that combination of SAMC treatment together with survivin knockdown might be a potential strategy for treatment of certain variants of ovarian cancers.


Assuntos
Cisteína/análogos & derivados , Regulação Neoplásica da Expressão Gênica , Proteínas Inibidoras de Apoptose/genética , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Western Blotting , Caderinas/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cisteína/farmacologia , Feminino , Alho/química , Humanos , Integrina beta1/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Survivina , Ensaio Tumoral de Célula-Tronco , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Biol Chem ; 290(46): 27618-32, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26363073

RESUMO

TRAF family member-associated NF-κB activator (TANK) is a negative regulator of canonical NF-κB signaling in the Toll-like receptor- and B-cell receptor-mediated signaling pathways. However, functions of TANK in viral infection-mediated NF-κB activation remain unclear. Here, we reported that TANK was cleaved by encephalomyocarditis virus 3C at the 197 and 291 glutamine residues, which depends on its cysteine protease activity. In addition, encephalomyocarditis virus 3C impaired the ability of TANK to inhibit TRAF6-mediated NF-κB signaling. Interestingly, we found that several viral proteases encoded by the foot and mouth disease virus, porcine reproductive and respiratory syndrome virus, and equine arteritis virus also cleaved TANK. Our results suggest that TANK is a novel target of some viral proteases, indicating that some positive RNA viruses have evolved to utilize their major proteases to regulate NF-κB activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cisteína Endopeptidases/metabolismo , Vírus da Encefalomiocardite/enzimologia , NF-kappa B/metabolismo , Proteólise , Fator 6 Associado a Receptor de TNF/metabolismo , Proteínas Virais/metabolismo , Proteases Virais 3C , Sequência de Aminoácidos , Cisteína Endopeptidases/genética , Equartevirus/enzimologia , Vírus da Febre Aftosa/enzimologia , Células HEK293 , Humanos , Dados de Sequência Molecular , Vírus da Síndrome Respiratória e Reprodutiva Suína/enzimologia , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Proteínas Virais/genética
15.
Urol Int ; 94(4): 464-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790869

RESUMO

INTRODUCTION: Inhibitor of growth 4 (ING4) is a tumor suppressor. However the role of ING4 in human bladder malignancy is unknown. In this study, ING4 expression in human bladder cancer and its potential effects were studied. MATERIALS AND METHODS: ING4 expression in 47 human bladder cancer tissues and paired adjacent normal tissues was detected by Western blotting, quantitative reverse transcription-polymerase chain reaction, and immunohistochemistry. The migration and cell cycle progression of SV-HUC-1 and T24 cells with aberrant ING4 expression were examined. RESULTS: ING4 protein and mRNA were significantly decreased in bladder cancer tissues. ING4 protein level was significantly lower in the group of patients over 50 years of age. ING4 knockdown caused more rapid cell migration and increased the population of SV-HUC-1 and T24 cells in the G2-M phase. CONCLUSION: Our data suggest a close connection between aberrant ING4 expression and the carcinogenesis of human bladder cells. ING4 may be a potential target for bladder cancer chemotherapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Idoso , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Homeodomínio/genética , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Interferência de RNA , Fatores de Tempo , Transfecção , Proteínas Supressoras de Tumor/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
16.
Antiviral Res ; 118: 20-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25766860

RESUMO

MicroRNA-122 (miR-122) is involved in the pathogenesis of several liver diseases, including chronic hepatitis B infection and hepatocellular carcinoma. This study aimed to explore the potential role of miR-122 in the interferon (IFN)-mediated suppression of hepatitis B virus (HBV) in hepatocytes. We found that elevated expression of suppressor of cytokine signaling 3 (SOCS3) following HBV infection, contributed to the inactivation of the IFN signaling pathway. Based on previous studies from our laboratory showing that miR-122 can modulate type I IFN expression by inhibiting SOCS1 expression, we analyzed the SOCS3 mRNA sequence for putative miR-122 binding sites. We demonstrate that miR-122 inhibits SOCS3 expression by targeting the 3'-untranslated region of the SOCS3 mRNA within the region 1887-1910 nucleotides. Finally, we demonstrate that significantly increased levels of IFN lead to decreased HBV expression in miR-122 mimic-treated Huh7 cells, whereas inhibition of endogenous miR-122 leads to enhanced viral production, owing to a marked decrease in IFN expression. Taken together, our results demonstrate that miR-122 down-regulates SOCS3, thus positively affecting the anti-HBV efficiency of endogenous type I IFN. Our study suggests that suppression of miR-122 induced by HBV infection, leads to the inactivation of IFN expression, which in turn enhances HBV replication, contributing to viral persistence and hepatocarcinogenesis.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Hepatócitos/virologia , Interferon Tipo I/metabolismo , MicroRNAs/metabolismo , Proteínas Supressoras da Sinalização de Citocina/antagonistas & inibidores , Regiões 3' não Traduzidas , Sítios de Ligação , Linhagem Celular , Regulação para Baixo , Humanos , Evasão da Resposta Imune , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética
17.
Oncol Lett ; 10(5): 2835-2841, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26722250

RESUMO

MicroRNA-181 (miR-181) has been recently demonstrated to participate in the differentiation and development of immune cells, including natural killer cells and B and T lymphocytes, and myeloid linages, including erythroid and megakaryocytic cells. The aberrant expression of miR-181, particularly low expression levels, has been observed in a number of leukemia types, including B-cell chronic lymphocytic leukemia and cytogenetically abnormal acute myeloid leukemia. However, the expression and function of miR-181 in chronic myeloid leukemia (CML) remains unknown. In the present study, the aberrant expression of miR-181a was analyzed in a patient with CML and in the CML K562 cell line. In addition, the function and potential mechanisms of miR-181a in K562 cells with regard to their chemotherapeutic sensitivity to imatinib were investigated. The expression levels of miR-181a were significantly reduced in the patient with CML and in the CML K562 cell line. Furthermore, the overexpression of miR-181a in the K562 cells enhanced the chemotherapeutic sensitivity of these cells to imatinib. The potential mechanism mediating these effects may be associated with the capacity of miR-181a to inhibit cell growth and/or to induce cells apoptosis and differentiation in K562 cells. The results of the present study suggested that miR-181a may be a target for the treatment of CML and a useful indicator of the therapeutic sensitivity of CML to imatinib.

18.
Virus Res ; 195: 207-16, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25456405

RESUMO

Enterovirus 71 (EV71) is the main causative pathogen of hand, foot, and mouth disease (HFMD). The severe neurological complications caused by EV71 infection and the lack of effective therapeutic medicine underline the importance of searching for antiviral substances. Pyrrolidine dithiocarbamate (PDTC), an antioxidant, has been reported to inhibit the replication of coxsackievirus B (CVB) through dysregulating ubiquitin-proteasome system (UPS). In this study, we demonstrated that PDTC exerted potent antiviral effect on EV71. Viral RNA synthesis, viral protein expression, and the production of viral progeny were significantly reduced by the treatment of PDTC in Vero cells infected with EV71. Similar to the previous report about the inhibitory effect of PDTC on UPS, we found that PDTC treatment led to decreased levels of polyubiquitinated proteins in EV71-infected cells. The inhibitory effect of PDTC on UPS was further confirmed by the increased accumulation of cell cycle regulatory proteins p21 and p53, which are normally degraded through UPS, while the expression levels of both proteins remained unchanged. We also showed that PDTC had no impact on the activity of proteasome. Thus, we demonstrated that the down-regulation of PDTC on UPS was the result of its inhibition on ubiquitination. More importantly, this study provides evidence that the inhibition on UPS was required for the antiviral activity of PDTC, since MG132, a potent proteasome inhibitor, significantly inhibited the cytopathic effect and viral protein synthesis in EV71-infected cells. We also found that the antioxidant property of PDTC did not contribute to its antiviral effect, since N-acetyl-l-cysteine, a potent antioxidant, could not inhibit viral replication. In addition, CPE and viral protein synthesis were not inhibited in the cells pretreated with PDTC 2h before viral infection and then cultured in the media with no PDTC supplement, while the antioxidant effect of PDTC was retained. PDTC also showed significant inhibition on apoptosis induced by EV71 infection when it was applied at the early stage of viral infection. Our results collectively suggest that PDTC could be a potential anti-EV71 compound which possesses both antiviral and anti-apoptotic capacity.


Assuntos
Antivirais/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Enterovirus Humano A/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Pirrolidinas/farmacologia , Tiocarbamatos/farmacologia , Ubiquitina/metabolismo , Replicação Viral/efeitos dos fármacos , Animais , Chlorocebus aethiops , Efeito Citopatogênico Viral/efeitos dos fármacos , RNA Viral/análise , Ubiquitinação/efeitos dos fármacos , Células Vero , Proteínas Virais/análise
19.
Virol J ; 11: 192, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25410318

RESUMO

BACKGROUND: Stress granules (SGs) are granular aggregates in the cytoplasm that are formed under a variety of stress situations including viral infection. Previous studies indicate that poliovirus, a member of Picornaviridae, can induce SG formation. However, the exact mechanism by which the picornaviruses induce SG formation is unknown. METHOD: The localization of SG markers in cells infected with coxsackievirus B3 (CVB3) or enterovirus 71 (EV71) and in cells expressing each viral protein was determined via immunofluorescence assays or plasmid transfection. Eight plasmids expressing mutants of the 2A protease (2A(pro)) of CVB3 were generated using a site-directed mutagenesis strategy. The cleavage efficiencies of eIF4G by CVB3 2A(pro) and its mutants were determined via western blotting assays. RESULTS: In this study, we found that CVB3 infection induced SG formation, as evidenced by the co-localization of some accepted SG markers in viral infection-induced granules. Furthermore, we identified that 2A(pro) of CVB3 was the key viral component that triggered SG formation. A 2A(pro) mutant with the G122E mutation, which exhibited very low cleavage efficiency toward eIF4G, significantly attenuated its capacity for SG induction, indicating that the protease activity was required for 2A(pro) to initiate SG formation. Finally, we observed that SGs also formed in EV71-infected cells. Expression of EV71 2A(pro) alone was also sufficient to cause SG formation. CONCLUSION: Both CVB3 and EV71 infections can induce SG formation, and 2A(pro) plays a crucial role in the induction of SG formation during these infections. This finding may help us to better understand how picornaviruses initiate the SG response.


Assuntos
Cisteína Endopeptidases/metabolismo , Grânulos Citoplasmáticos/metabolismo , Enterovirus Humano A/fisiologia , Enterovirus Humano B/fisiologia , Interações Hospedeiro-Patógeno , Proteínas Virais/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Imunofluorescência , Humanos , Proteólise
20.
Virus Res ; 192: 52-61, 2014 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-25148713

RESUMO

Stress granules (SGs) are cytoplasmic granules that are formed in cells when stress occurs. In this study, we found that SGs formed in cells infected with coxsackievirus B3 (CVB3), evidenced with the co-localization of some accepted SG markers in the viral infection-induced granules. We further discovered that adenosine-uridine (AU)-rich element RNA binding factor 1 (AUF1), which can bind to mRNAs and regulate their translation, was recruited to the SGs in response to high dose of CVB3 by detecting the co-localization of AUF1 with SG markers. Similar results were also observed in the enterovirus 71 (EV71)-infected cells. Finally, we demonstrated that AUF1 was also recruited to arsenite-induced SGs, suggesting that the recruitment of AUF1 to SG is not a specific response to viral infection. In summary, our data indicate that both CVB3 and EV71 infections can induce SG formation, and AUF1 is a novel SG component upon the viral infections. Our findings may shed light on understanding the picornavirus-host interaction.


Assuntos
Grânulos Citoplasmáticos/química , Enterovirus Humano B/fisiologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/análise , Interações Hospedeiro-Patógeno , Arsenitos/toxicidade , Enterovirus Humano A/fisiologia , Células HeLa , Ribonucleoproteína Nuclear Heterogênea D0 , Humanos , Microscopia Confocal , Microscopia de Fluorescência , Estresse Fisiológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA