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1.
J Appl Clin Med Phys ; 23(11): e13758, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36107021

RESUMO

INTRODUCTION: To explore and evaluate the performance of MRI-based brain tumor super-resolution generative adversarial network (MRBT-SR-GAN) for improving the MRI image resolution in brain tumors. METHODS: A total of 237 patients from December 2018 and April 2020 with T2-fluid attenuated inversion recovery (FLAIR) MR images (one image per patient) were included in the present research to form the super-resolution MR dataset. The MRBT-SR-GAN was modified from the enhanced super-resolution generative adversarial networks (ESRGAN) architecture, which could effectively recover high-resolution MRI images while retaining the quality of the images. The T2-FLAIR images from the brain tumor segmentation (BRATS) dataset were used to evaluate the performance of MRBT-SR-GAN contributed to the BRATS task. RESULTS: The super-resolution T2-FLAIR images yielded a 0.062 dice ratio improvement from 0.724 to 0.786 compared with the original low-resolution T2-FLAIR images, indicating the robustness of MRBT-SR-GAN in providing more substantial supervision for intensity consistency and texture recovery of the MRI images. The MRBT-SR-GAN was also modified and generalized to perform slice interpolation and other tasks. CONCLUSIONS: MRBT-SR-GAN exhibited great potential in the early detection and accurate evaluation of the recurrence and prognosis of brain tumors, which could be employed in brain tumor surgery planning and navigation. In addition, this technique renders precise radiotherapy possible. The design paradigm of the MRBT-SR-GAN neural network may be applied for medical image super-resolution in other diseases with different modalities as well.


Assuntos
Neoplasias Encefálicas , Aprendizado Profundo , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Neoplasias Encefálicas/diagnóstico por imagem
2.
Cancer Cell Int ; 19: 269, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636512

RESUMO

BACKGROUND: Malignant glioma is one of the essentially incurable tumors with chemoresistance and tumor recurrence. As a histone methyltransferase, SUV39H2 can trimethylate H3K9. SUV39H2 is highly expressed in many types of human tumors, while the function of SUV39H2 in the development and progression of glioma has never been elucidated. METHODS: RT-qPCR and IHC were used to test SUV39H2 levels in glioma tissues and paired normal tissues. The clinical relevance of SUV39H2 in glioma was analyzed in a public database. Colony formation assays, CCK-8 assays, and flow cytometry were conducted to explore the role of SUV39H2 in the growth of glioma cells in vitro. A cell line-derived xenograft model was applied to explore SUV39H2's role in U251 cell proliferation in vivo. Sphere formation assays, RT-qPCR, flow cytometry, and IF were conducted to illustrate the role of SUV39H2 in the stemness and chemosensitivity of glioma. Luciferase reporter assays and WB were applied to determine the function of SUV39H2 in Hh signaling. RESULTS: SUV39H2 was highly expressed in glioma tissues relative to normal tissues. SUV39H2 knockdown inhibited cell proliferation and stemness and promoted the chemosensitivity of glioma cells in vitro. In addition, SUV39H2 knockdown also significantly inhibited glioma cell growth in vivo. Moreover, we further uncovered that SUV39H2 regulated hedgehog signaling by repressing HHIP expression. CONCLUSIONS: Our findings delineate the role of SUV39H2 in glioma cell growth and chemosensitivity as a pivotal regulator of the hedgehog signaling pathway and may support SUV39H2 as a potential target for diagnosis and therapy in glioma management.

3.
J Craniofac Surg ; 30(5): e400-e402, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31299791

RESUMO

The study reported a case of an intrasellar arachnoid cyst with visual disturbances as the main symptom. Arachnoid cyst is a common intracranial benign space-occupying lesion, but rarely seen in intrasellar region with less than 100 cases reported available in English language literature. Therefore, it is still controversial about the diagnosis and treatment of such patients. This article reviewed previous literature and discussed the differential diagnosis and surgical strategies of intrasellar arachnoid cyst in combination with our own case.


Assuntos
Cistos Aracnóideos/diagnóstico , Diagnóstico Diferencial , Adulto , Cistos Aracnóideos/cirurgia , Feminino , Humanos , Sela Túrcica/patologia
4.
J Craniofac Surg ; 29(2): 449-451, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29239918

RESUMO

Granulomatosis with polyangiitis (GPA) is a necrotizing granulomatous vasculitis occasionally affecting central nervous system (CNS), and GPA patients with initial CNS symptoms are even rarer, whose diagnosis is further confused by an absence of positive antineutrophil cytoplasmic antibody. The authors described the characteristics of antineutrophil cytoplasmic antibody -negative GPA with CNS onset in a patient and discussed on its management, which may contribute to future diagnosis and treatment of patients with similar conditions.


Assuntos
Doenças do Sistema Nervoso Central , Granulomatose com Poliangiite , Anticorpos Anticitoplasma de Neutrófilos , Humanos
5.
Neurochem Res ; 42(4): 1044-1056, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28236213

RESUMO

Early brain injury (EBI) following subarachnoid hemorrhage (SAH) is the main cause to poor outcomes of SAH patients, and early inflammation plays an important role in the acute pathophysiological events. It has been demonstrated that ethyl pyruvate (EP) has anti-inflammatory and neuroprotective effects in various critical diseases, however, the role of EP on EBI following SAH remains to be elucidated. Our study aimed to evaluate the effects of EP on EBI following SAH in the endovascular perforation rabbit model. All rabbits were randomly divided into three groups: sham, SAH + Vehicle (equal volume) and SAH + EP (30 mg/kg/day). MRI was performed to estimate the reliability of the EBI at 24 and 72 h after SAH. Neurological scores were recorded to evaluate the neurological deficit, ELISA kit was used to measure the level of tumor necrosis factor-α (TNF-α), and western blot was used to detect the expression of TNF-α, tJNK, pJNK, bax and bcl-2 at 24 and 72 h after SAH. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Fluoro-jade B (FJB) staining were used to detect neuronal apoptosis and neurodegeneration respectively, meanwhile hematoxylin and eosin (H&E) staining was used to assess the degree of vasospasm. Our results demonstrated that EP alleviated brain tissue injury (characterized by diffusion weighted imaging and T2 sequence in MRI scan), and significantly improved neurological scores at 72 h after SAH. EP decreased the level of TNF-α and downregulated pJNK/tJNK and bax/bcl-2 in cerebral cortex and hippocampus effectively both at 24 and 72 h after SAH. Furthermore, EP reduced TUNEL and FJB positive cells significantly. In conclusion, the present study supported that EP afforded neuroprotective effects possibly via reducing TNF-α expression and inhibition of the JNK signaling pathway. Therefore, EP may be a potent therapeutic agent to attenuate EBI following SAH.


Assuntos
Anti-Inflamatórios/uso terapêutico , Lesões Encefálicas/prevenção & controle , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Piruvatos/uso terapêutico , Hemorragia Subaracnóidea/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/metabolismo , Procedimentos Endovasculares/efeitos adversos , Sistema de Sinalização das MAP Quinases/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Piruvatos/farmacologia , Coelhos , Distribuição Aleatória , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/metabolismo
6.
Mediators Inflamm ; 2015: 520745, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25873763

RESUMO

Hypothermia treatment is a promising therapeutic strategy for brain injury. We previously demonstrated that 5'-adenosine monophosphate (5'-AMP), a ribonucleic acid nucleotide, produces reversible deep hypothermia in rats when the ambient temperature is appropriately controlled. Thus, we hypothesized that 5'-AMP-induced hypothermia (AIH) may attenuate brain ischemia/reperfusion injury. Transient cerebral ischemia was induced by using the middle cerebral artery occlusion (MCAO) model in rats. Rats that underwent AIH treatment exhibited a significant reduction in neutrophil elastase infiltration into neuronal cells and matrix metalloproteinase 9 (MMP-9), interleukin-1 receptor (IL-1R), tumor necrosis factor receptor (TNFR), and Toll-like receptor (TLR) protein expression in the infarcted area compared to euthermic controls. AIH treatment also decreased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling- (TUNEL-) positive neuronal cells. The overall infarct volume was significantly smaller in AIH-treated rats, and neurological function was improved. By contrast, rats with ischemic brain injury that were administered 5'-AMP without inducing hypothermia had ischemia/reperfusion injuries similar to those in euthermic controls. Thus, the neuroprotective effects of AIH were primarily related to hypothermia.


Assuntos
Monofosfato de Adenosina/farmacologia , Hipotermia Induzida , Inflamação/prevenção & controle , Traumatismo por Reperfusão/terapia , Animais , Apoptose , Circulação Cerebrovascular , Modelos Animais de Doenças , Frequência Cardíaca/efeitos dos fármacos , Elastase de Leucócito/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Receptores Toll-Like/fisiologia
7.
J Craniofac Surg ; 25(6): 2105-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25304144

RESUMO

The objective of this study was to investigate the diagnosis and surgical treatment of central brain herniations caused by traumatic bifrontal contusions. A total of 63 patients (45 men and 18 women; mean age of 43 years with a range from 20 to 72 years) who suffered from traumatic bifrontal contusions between January 2007 and December 2012 were inspected. The clinical and imaging results were studied for all patients, and we found that swelling of the mesencephalon and a downward shift of the bilateral red nucleus were significant signs of central brain herniation in the image of magnetic resonance imaging. All patients were given a simultaneous bilateral craniotomy for balanced decompressive surgery. The Glasgow Outcome Scale was used to monitor the patients during the follow-up period, which lasted from 6 to 52 months with a mean of 22 months. At the termination of the follow-up period, the following Glasgow Outcome Scale scores were obtained: 14 patients scored 5 points, 22 patients scored 4 points, 7 patients scored 3 points, 13 patients scored 2 points, and 7 patients scored 1 point. Therefore, our study suggested that an early magnetic resonance imaging scan could result in a more timely diagnosis of central brain herniation, and simultaneous bilateral craniotomy was found to be one of the best treatments for central brain herniation to improve patient outcomes.


Assuntos
Lesões Encefálicas/complicações , Encefalocele/diagnóstico , Osso Frontal/lesões , Adulto , Idoso , Craniotomia/métodos , Descompressão Cirúrgica/métodos , Diagnóstico Precoce , Encefalocele/etiologia , Encefalocele/cirurgia , Feminino , Seguimentos , Escala de Coma de Glasgow , Escala de Resultado de Glasgow , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Mesencéfalo/lesões , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Núcleo Rubro/lesões , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
8.
iScience ; 27(5): 109698, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38655198

RESUMO

Mounting evidence supports the role of neuroinflammation in radiation-induced brain injury (RIBI), a chronic disease characterized by delayed and progressive neurological impairment. Asparagine endopeptidase (AEP), also known as legumain (LGMN), participates in multiple malignancies and neurodegenerative diseases and may potentially be involved in RIBI. Here, we found AEP expression was substantially elevated in the cortex and hippocampus of wild-type (Lgmn+/+) mice following whole-brain irradiation. Lgmn knockout (Lgmn-/-) alleviated neurological impairment caused by whole-brain irradiation by suppressing neuronal senescence. Bulk RNA and metabolomic sequencing revealed AEP's involvement in the antigen processing and presentation pathway and neuroinflammation. This was further confirmed by co-culturing Lgmn+/+ primary neurons with the conditioned media derived from irradiated Lgmn+/+ or Lgmn-/- primary microglia. Furthermore, esomeprazole inhibited the enzymatic activity of AEP and RIBI. These findings identified AEP as a critical factor of neuroinflammation in RIBI, highlighting the prospect of targeting AEP as a therapeutic approach.

9.
Int J Mol Sci ; 13(5): 6089-6101, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22754351

RESUMO

Transient forebrain or global ischemia induces neuronal death in vulnerable CA1 pyramidal cells with many features. A brief period of ischemia, i.e., ischemic preconditioning, or a modified reperfusion such as ischemic postconditioning, can afford robust protection of CA1 neurons against ischemic challenge. Therefore, we investigated the effect of ischemic preconditioning and postconditioning on neural cell apoptosis in rats. The result showed that both ischemic preconditioning and postconditioning may attenuate the neural cell death and DNA fragment in the hippocampal CA1 region. Further western blot study suggested that ischemic preconditioning and postconditioning down-regulates the protein of cleaved caspase-3, caspase-6, caspase-9 and Bax, but up-regulates the protein Bcl-2. These findings suggest that ischemic preconditioning and postconditioning have a neuroprotective role on global brain ischemia in rats through the same effect on inhibition of apoptosis.


Assuntos
Isquemia Encefálica/patologia , Região CA1 Hipocampal/irrigação sanguínea , Pós-Condicionamento Isquêmico/métodos , Precondicionamento Isquêmico/métodos , Neurônios/citologia , Animais , Apoptose , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Região CA1 Hipocampal/patologia , Caspases/metabolismo , Células Cultivadas , Fragmentação do DNA , Modelos Animais de Doenças , Regulação da Expressão Gênica , Neurônios/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína X Associada a bcl-2/metabolismo
10.
Mol Ther Nucleic Acids ; 27: 109-121, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-34938610

RESUMO

LncRNA PVT1 has been implicated in numerous pathophysiological processes and diseases, especially cancers. However, the role and mechanism of PVT1 in the tumorigenesis of glioblastoma remain unclear. We investigated the alteration of PVT1 and its key functions in glioblastoma. PVT1 was upregulated and associated with poor prognosis in glioblastoma. We demonstrated that PVT1 silencing suppressed cell proliferation, colony formation, and orthotopic xenograft tumor growth. Mechanistic investigations found that PVT1 interacted with TRIM24 directly and increased its protein stability. PVT1 recruited COPS5 to deubiquitinate TRIM24; reciprocally, PVT1 depletion impaired the interaction between COPS5 and TRIM24, resulting in decreased expression of TRIM24. PVT1, TRIM24, and COPS5 coordinately contributed to the activation of STAT3 signaling and malignant phenotype of glioblastoma. Collectively, this study elucidates the essential role of PVT1 in the tumorigenesis of glioblastoma, which provides candidacy therapeutic target for glioblastoma treatment.

11.
Mol Biol Rep ; 38(5): 3235-42, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20182801

RESUMO

Pyruvate, an endogenous metabolite of glycolysis, is an anti-toxicity agent. Recent studies have suggested possible roles for pyruvate in protecting CNS neurons from excitotoxic and metabolic insults. Utilizing cultures derived from embryonic rat cortex, the studies presented in this paper indicate that an astroglia-mediated mechanism is involved in the neuroprotective effects of pyruvate against glutamate toxicity. Glutamate-induced toxicity could be reversed by pyruvate in a mixed culture of cortex cells. Importantly, in pure neuronal cultures from the same tissue, pyruvate failed to protect against glutamate toxicity. Addition of astroglia to the pure neuronal cultures restores the ability of pyruvate to protect neurons from glutamate-induced toxicity. Our results further suggest that pyruvate can induce glia to up-regulate the synthesis of glutathione (GSH), an antioxidant that protects cells from toxins such as free radicals. Taken together, our data suggest that astroglia in mixed cultures are essential for mediating the effects of pyruvate, revealing a novel mechanism by which pyruvate, an important intermediate of tricarboxylic acid cycle in the body, may act to protect neurons from damage during insults such as brain ischemia.


Assuntos
Astrócitos/metabolismo , Ácido Glutâmico/toxicidade , Glutationa/metabolismo , Neurônios/efeitos dos fármacos , Ácido Pirúvico/metabolismo , Animais , Astrócitos/citologia , Células Cultivadas , Técnicas de Cocultura , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/metabolismo , Ratos , Ratos Long-Evans
12.
Int J Mol Sci ; 11(1): 140-53, 2010 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-20162006

RESUMO

Transient forebrain or global ischemia induces cell death in vulnerable CA1 pyramidal neurons. A brief period of ischemia, i.e., ischemic preconditioning, affords CA1 neurons robust protection against a subsequent, more prolonged ischemic challenge. Using the four-vessel occlusion model, we established an ischemic preconditioning model in which rodents were subjected to 3 min of sublethal ischemia 48 h before a 15 min lethal ischemia. We showed that preconditioning attenuated the ischemia-induced neural cell death and DNA fragmentation in the hippocampal CA1 region. RT-PCR and western blot analysis showed that preconditioning prior to an ischemic insult significantly increased ASIC 2a mRNA and protein expression in comparison to the ischemic insult alone (p < 0.01). These findings implicate a new role of ASIC 2a on endogenous neuroprotection from ischemic insult.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Isquemia Encefálica/metabolismo , Precondicionamento Isquêmico , Canais Iônicos Sensíveis a Ácido/genética , Análise de Variância , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Masculino , Fármacos Neuroprotetores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Regulação para Cima
13.
Int J Mol Sci ; 11(11): 4407-16, 2010 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21151445

RESUMO

Ischemic postconditioning refers to several transient reperfusion and ischemia cycles after an ischemic event and before a long duration of reperfusion. The procedure produces neuroprotective effects. The mechanisms underlying these neuroprotective effects are poorly understood. In this study, we found that most neurons in the CA1 region died after 10 minutes of ischemia and is followed by 72 hours of reperfusion. However, brain ischemic postconditioning (six cycles of 10 s/10 s reperfusion/re-occlusion) significantly reduced neuronal death. Significant up-regulation of Glutamate transporter-1 was found after 3, 6, 24, 72 hours of reperfusion. The present study showed that ischemic postconditioning decreases cell death and that upregulation of GLT-1 expression may play an important role on this effect.


Assuntos
Região CA1 Hipocampal/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Pós-Condicionamento Isquêmico , Traumatismo por Reperfusão/metabolismo , Animais , Região CA1 Hipocampal/irrigação sanguínea , Região CA1 Hipocampal/patologia , Morte Celular , Transportador 2 de Aminoácido Excitatório/genética , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/terapia
14.
Cyberpsychol Behav Soc Netw ; 23(5): 351-356, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32283040

RESUMO

Live stream services have emerged as a highly profitable Internet application in recent years with rapidly growing audiences for this form of instant and interactive Internet media. This study applies media richness theory along with uses and gratifications theory to predict user loyalty to live stream services. The proposed model is empirically evaluated using survey data collected from 295 users responding about their perception of such services. Empirical results show that perceived media richness and gratifications such as entertainment and sociability are antecedents of loyalty, while immediate feedback is the most salient facet of perceived media richness. The results provide further useful insights for service providers and streamers to build loyal user bases.


Assuntos
Meios de Comunicação , Comportamento do Consumidor , Internet , Humanos
15.
Aging (Albany NY) ; 12(1): 318-339, 2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31905344

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are widely expressed non-coding RNAs in eukaryotic cells, involved in regulating tumorigenesis of several types of cancers. However, the expression profiles and the precise functional role in glioblastoma remain unclear. RESULTS: Circ-EPB41L5 was downregulated in glioblastoma tissues and cell lines compared to the normal brain tissues and cell lines. Low circ-EPB41L5 expression was correlated to the poor prognosis of glioblastoma patients, while the overexpression inhibited proliferation, clone formation, migration, and invasion abilities of glioma cells, and the suppression had counter effects. Furthermore, RNA-seq results determined that the host gene was the target gene of circ-EPB41L5, which served as a sponge against miR-19a and inhibited miR-19a activity from upregulating the expression of EPB41L5. Finally, we found that circ-EPB41L5 regulated the RhoC expression and phosphorylation of AKT through EPB41L5. CONCLUSION: The current study highlights a novel suppressive function of circ-EPB41L5 and reveals that circ-EPB41L5/miR-19a/EPB41L5/p-AKT regulatory axis plays a striking role in the progression of glioblastoma, which provides a novel insight into the mechanisms underlying glioblastoma. METHODS: The expression profiles of circRNAs in glioblastoma were determined by Illumina HiSeq from six glioblastoma tissues and six normal brain tissues. Then, the correlation between circ-EPB41L5 expression and clinical features and the survival time of 45 glioblastoma patients was detected. The interaction between circ-EPB41L5, miR-19a, and EPB41L5 was assessed by luciferase reporter and RNA pull-down assays. The effects of expression of the ectopic intervention of circ-EPB41L5 or EPB41L5 on proliferation, clone formation, migration, and invasion in vitro and tumorigenesis in vivo were observed to evaluate the function of circ-EPB41L5 or EPB41L5.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Proteínas de Membrana/genética , MicroRNAs/genética , RNA Circular , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Interferência de RNA , Carga Tumoral
16.
J Natl Cancer Inst ; 112(4): 343-355, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400201

RESUMO

BACKGROUND: Isocitrate dehydrogenase wild-type (WT) glioblastoma (GBM) accounts for 90% of all GBMs, yet only 27% of isocitrate dehydrogenase WT-GBMs have p53 mutations. However, the tumor surveillance function of WT-p53 in GBM is subverted by mechanisms that are not fully understood. METHODS: We investigated the proteolytic inactivation of WT-p53 by asparaginyl endopeptidase (AEP) and its effects on GBM progression in cancer cells, murine models, and patients' specimens using biochemical and functional assays. The sera of healthy donors (n = 48) and GBM patients (n = 20) were examined by enzyme-linked immunosorbent assay. Furthermore, effects of AEP inhibitors on GBM progression were evaluated in murine models (n = 6-8 per group). The statistical significance between groups was determined using two-tailed Student t tests. RESULTS: We demonstrate that AEP binds to and directly cleaves WT-p53, resulting in the inhibition of WT-p53-mediated tumor suppressor function in both tumor cells and stromal cells via extracellular vesicle communication. High expression of uncleavable p53-N311A-mutant rescue AEP-induced tumorigenesis, proliferation, and anti-apoptotic abilities. Knock down or pharmacological inhibition of AEP reduced tumorigenesis and prolonged survival in murine models. However, overexpression of AEP promoted tumorigenesis and shortened the survival time. Moreover, high AEP levels in GBM tissues were associated with a poor prognosis of GBM patients (n = 83; hazard ratio = 3.94, 95% confidence interval = 1.87 to 8.28; P < .001). A correlation was found between high plasma AEP levels and a larger tumor size in GBM patients (r = 0.6, P = .03), which decreased dramatically after surgery. CONCLUSIONS: Our results indicate that AEP promotes GBM progression via inactivation of WT-p53 and may serve as a prognostic and therapeutic target for GBM.


Assuntos
Cisteína Endopeptidases/metabolismo , Glioblastoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/farmacologia , Progressão da Doença , Glioblastoma/enzimologia , Glioblastoma/patologia , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Transgênicos , Células Estromais/enzimologia , Células Estromais/metabolismo , Células Estromais/patologia
17.
Mol Med Rep ; 20(3): 2365-2372, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322214

RESUMO

The current study used a rat middle cerebral artery occlusion (MCAO) model with the aim to explore the effects of compound porcine cerebroside and ganglioside injection (CPCGI) on brain ischemia/reperfusion injury in rats. Improvement in the infarct­side microcirculation and the overall recovery of neurological function were detected by triphenyltetrazolium chloride staining, laser speckle blood flow monitoring, latex perfusion, immunofluorescence and immunoblotting. The results revealed that administration of CPCGI for 7 consecutive days following ischemic stroke contributed to the recovery of neurological function and the reduction of cerebral infarct volume in rats. Blood flow monitoring results demonstrated that the administration of CPCGI effectively promoted cerebral blood flow following stroke, and contributed to the protection of the ischemic side blood vessels. In addition, CPCGI treatment increased the numbers of new blood vessels in the peripheral ischemic region, and upregulated the expression levels of vascular endothelial growth factor, angiopoietin 1 and its receptor TEK receptor tyrosine kinase, fibroblast growth factor and Wnt signaling pathway­associated proteins. Taken together, the present results indicated that CPCGI improved the blood circulation and neurological function following cerebral ischemia/reperfusion in rats.


Assuntos
Cerebrosídeos/uso terapêutico , Gangliosídeos/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Cerebrosídeos/administração & dosagem , Gangliosídeos/administração & dosagem , Infarto da Artéria Cerebral Média/fisiopatologia , Injeções , Masculino , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/fisiopatologia
18.
Mater Sci Eng C Mater Biol Appl ; 96: 96-104, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606608

RESUMO

Drug resistance induced by increasing intracellular levels of detoxifying agents for conventional platinum(II) drugs such as metallothioneins (MTs) and glutathione (GSH) are the major obstacles for widely used platinum-based chemotherapeutic cancer treatment. Here, we developed trans-geometry platinum (II) drugs with sterically hindered bulky ligands PyPt which is able to hind the GSH attack of platinum drug to overcome cisplatin resistance. Moreover, the PyPt can self-assemble with biodegradable copolymer mPEG-PGA into uniform nanoparticles with PyPt drugs in the polymeric core and PEG as the shell, further protecting PyPt from GSH detoxification to further slow the reaction rate with GSH in vivo. This strategy was developed to bring benefit of not only increasing the solubility of sterically hindered platinum drugs but also combating cisplatin resistance. The M(PyPt) exhibited environment controlled releasing of Pt in tumor micro-environment which prohibited the division of cancer cells. Furthermore, due to the increasing solubility of nanoparticle encapsulated PyPt, the cellular uptake and cytotoxicity of M(PyPt) against both cancer resistance cells was enhanced compared to the cisplatin and PyPt through evaluating with flow cytometry and MTT, respectively. Thus, it was concluded that the M(PyPt) was capable to successfully overcome the cisplatin resistance in the drug-resistant cell line, indicating its potential application in the treatment of clinical cancers with strong cisplatin resistance. Hence the M(PyPt) strategy may represent a promising novel drug delivery system for the local treatment of drug resistance cancer.


Assuntos
Cisplatino , Sistemas de Liberação de Medicamentos/métodos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Linhagem Celular , Cisplatino/química , Cisplatino/farmacocinética , Cisplatino/farmacologia , Humanos , Neoplasias/metabolismo , Neoplasias/patologia
19.
Neuro Oncol ; 21(10): 1284-1296, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31504797

RESUMO

BACKGROUND: Circular RNAs (circRNAs), a newly discovered type of endogenous noncoding RNA, have been proposed to mediate the progression of diverse types of tumors. Systematic studies of circRNAs have just begun, and the physiological roles of circRNAs remain largely unknown. Here, we focused on elucidating the potential role and molecular mechanism of circular forkhead box O3 (circFOXO3) in glioblastoma (GBM) progression. METHODS: First, we analyzed circFOXO3 alterations in GBM and noncancerous tissues through real-time quantitative reverse transcription PCR (qRT-PCR). Next, we used loss- and gain-of-function approaches to evaluate the effect of circFOXO3 on GBM cell proliferation and invasion. Mechanistically, fluorescent in situ hybridization, RNA pull-down, dual luciferase reporter, and RNA immunoprecipitation assays were performed to confirm the interaction between circFOXO3 and miR-138-5p/miR-432-5p in GBM. An animal model was used to verify the in vitro experimental findings. RESULTS: CircFOXO3 expression was significantly higher in GBM tissues than in noncancerous tissues. GBM cell proliferation and invasion were reduced by circFOXO3 knockdown and enhanced by circFOXO3 overexpression. Further biochemical analysis showed that circFOXO3 exerted its pro-tumorigenic activity by acting as a competing endogenous RNA (ceRNA) to increase expression of nuclear factor of activated T cells 5 (NFAT5) via sponging both miR-138-5p and miR-432-5p. Notably, tumor inhibition by circFOXO3 downregulation could be reversed by miR-138-5p/miR-432-5p inhibitors in GBM cells. Moreover, GBM cells with lower circFOXO3 expression developed less aggressive tumors in vivo. CONCLUSIONS: Our data demonstrate that circFOXO3 can exert regulatory functions in GBM and that ceRNA-mediated microRNA sequestration might be a potential strategy for GBM therapy.


Assuntos
Neoplasias Encefálicas/patologia , Proteína Forkhead Box O3/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/patologia , Fatores de Transcrição/genética , Animais , Neoplasias Encefálicas/genética , DNA Circular/genética , Progressão da Doença , Glioblastoma/genética , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Fatores de Transcrição/metabolismo
20.
Int J Oncol ; 54(1): 261-270, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30387845

RESUMO

Glioblastoma multiforme (GBM) has the highest mortality rate among patients with brain tumors, and radiotherapy forms an important part of its treatment. Thus, there is an urgent requirement to elucidate the mechanisms conferring GBM progression and radioresistance. In the present study, it was identified that antisense transcript of hypoxia­inducible factor­1α (AHIF) was significantly upregulated in GBM cancerous tissues, as well as in radioresistant GBM cells. The expression of AHIF was also upregulated in response to radiation. Knockdown of AHIF in GBM cells decreased viability and invasive capacities, and increased the proportion of apoptotic cells. By contrast, overexpression of AHIF in GBM cells increased viability and invasive capacities, and decreased the proportion of apoptotic cells. Furthermore, exosomes derived from AHIF­knockdown GBM cells inhibited viability, invasion and radioresistance, whereas exosomes derived from AHIF­overexpressing GBM cells promoted viability, invasion and radioresistance. Further biochemical analysis identified that AHIF regulates factors associated with migration and angiogenesis in exosomes. To the best of our knowledge, the present study is the first to establish that AHIF promotes glioblastoma progression and radioresistance via exosomes, which suggests that AHIF is a potential therapeutic target for GBM.


Assuntos
Neoplasias Encefálicas/metabolismo , Exossomos/genética , Glioblastoma/metabolismo , RNA Longo não Codificante/genética , Tolerância a Radiação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Sobrevivência Celular , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Regulação para Cima , Adulto Jovem
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