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1.
Chem Commun (Camb) ; 57(72): 9148-9151, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34498611

RESUMO

As a promising 19F MRI tracer, the relatively slow lattice-spin relaxation of CaF2 nanocrystals leads to an unacceptable scanning time in MR imaging, hampering their application. We herein controlled the size and lattice distortion of CaF2 nanocrystals and showed that the shortened interplanar spacing pronouncedly sped up the longitude relaxation.

2.
Acta Biomater ; 131: 508-518, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34214663

RESUMO

Radio-sensitization is highly desired to reduce side-effect of the harsh dose of radiation therapy (RT), for which nanoparticles with high atomic number elements provide a promising tool. However, insufficient knowledge on utilizing the interaction between nanoparticles and cancerous cells hampers the improvement of therapeutic outcome. We herein employed NaGdF4:Yb,Er nano-crystals as the sensitizer, and modified them with a tumor targeting agent and a mitochondria targeting moiety, separately and jointly, to achieve varied extent of mitochondrial accumulation. We observed that NaGdF4:Yb,Er nano-crystal, even unmodified with targeting ligands, is effective for radio-sensitization. Furthermore, the extent of mitochondrial targeting was responsible for sensitization efficiency both in vitro and in vitro. By RNA sequencing technique, the result was ascribed to the reactive oxygen species (ROS) mediated TNF-JNK pathway and cell cycle arrest besides breaking DNA, in contrast to only DNA damage only with those untargeted nanoparticles. Our work indicated that ROS generated by the irradiation can be utilized by activating an alternative apoptotic pathway with mitochondrial targeting nanoparticles, and therefore may suggest an approach for the enhancement of radio-sensitization. STATEMENT OF SIGNIFICANCE: Radiosensitization by nanoparticles could reduce the burden of cancer due to lowering the dose of radiation therapy and reducing side-effect. How to fully utilize the interactions of irradiation-nanoparticles-biotissues remains a challenge for improving the outcome of radiosensitization. In this manuscript, by modifying tumor-targeting and mitochondria-targeting ligands on nanoparticles, separately and jointly, we demonstrated that the radiosensitization efficiency of NaGdF4:Yb,Er nanoparticle depends on the extent of accumulation near mitochondria. By RNA-seq technique, the RT sensitization with mitochondrial targeting was ascribed to ROS-mediated TNF-JNK pathway and cell cycle arrest, in contrast to only DNA breaks with untargeted nanoparticles. The results suggested a strategy for better utilization of the energy of therapeutic irradiation and demonstrate that subcellular targeting is a potent factor for designing nanoparticulate radiosensitizers.


Assuntos
Nanopartículas , Neoplasias , Radiossensibilizantes , Humanos , Mitocôndrias , Radiossensibilizantes/farmacologia , Espécies Reativas de Oxigênio
3.
FEBS J ; 288(22): 6447-6464, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34089566

RESUMO

Although the increase in the number of identified posttranslational modifications (PTMs) has substantially improved our knowledge about substrate site specificity of single PTMs, the fact that different types of PTMs can crosstalk and act in concert to exert important regulatory mechanisms for protein function has not gained much attention. Here, we show that protein kinase Cδ (PKCδ) is SUMOylated at lysine 473 in its C-terminal catalytic domain, and the SUMOylation increases PKCδ stability by repressing its ubiquitination. In addition, we uncover a functional interplay between the phosphorylation and SUMOylation of PKCδ, which can strengthen each other through recruiting SUMO E2/E3 ligases and the PKCδ kinase, respectively, to the PKCδ complexes. We identified PIAS2ß as the SUMO E3 ligase of PKCδ. More importantly, by enhancing PKCδ protein stability and its phosphorylation through an interdependent interplay of the PTMs, the SUMOylation of PKCδ promotes apoptotic cell death induced by H2 O2 . We conclude that SUMOylation represents an important regulatory mechanism of PKCδ PTMs for the kinase's function in oxidative cell damage.


Assuntos
Apoptose , Proteína Quinase C-delta/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células CHO , Cricetulus , Peróxido de Hidrogênio/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Sumoilação
4.
Aging (Albany NY) ; 12(22): 22550-22563, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159013

RESUMO

XL388 is a highly efficient and orally-available ATP-competitive PI3K-mTOR dual inhibitor. Its activity against glioma cells was studied here. In established and primary human glioma cells, XL388 potently inhibited cell survival and proliferation as well as cell migration, invasion and cell cycle progression. The dual inhibitor induced significant apoptosis activation in glioma cells. In A172 cells and primary human glioma cells, XL388 inhibited Akt-mTORC1/2 activation by blocking phosphorylation of Akt and S6K1. XL388-induced glioma cell death was only partially attenuated by a constitutively-active mutant Akt1. Furthermore, it was cytotoxic against Akt1-knockout A172 glioma cells. XL388 downregulated MAF bZIP transcription factor G (MAFG) and inhibited Nrf2 signaling, causing oxidative injury in glioma cells. Conversely, antioxidants, n-acetylcysteine, pyrrolidine dithiocarbamate and AGI-106, alleviated XL388-induced cytotoxicity and apoptosis in glioma cells. Oral administration of XL388 inhibited subcutaneous A172 xenograft growth in severe combined immunodeficient mice. Akt-S6K1 inhibition and MAFG downregulation were detected in XL388-treated A172 xenograft tissues. Collectively, XL388 efficiently inhibits human glioma cell growth, through Akt-mTOR-dependent and -independent mechanisms.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Sulfonas/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos SCID , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Front Psychol ; 11: 1516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714254

RESUMO

With improvements in treatments for primary tumor and brain metastases (BM), the life expectancy of patients with advanced cancers is increasing; thus, helping patients with BM maintain quality of life is becoming increasingly important. Sense of coherence (SOC) has been found to be closely related to health-related quality of life (HRQoL) in patients with chronic diseases, however, this relationship has not been validated in patients with BM. This study first examined the relationship between SOC and HRQoL in patients with BM, and further identified factors associated with SOC in these patients. Patients with BM reported lower scores for most of the functioning subscales and for the general rating of quality of life, and higher scores for most of the symptom subscales, compared with a normative sample. SOC was significantly correlated with most aspects of HRQoL in patients with BM. Further, SOC in the patients was associated with awareness of the disease, possession of religious belief, and type of primary cancer. These results validate the close relationship between SOC and HRQoL in patients with BM, and indicate that SOC is associated with awareness of illness and religious belief.

6.
Cell Death Differ ; 27(11): 3146-3161, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32483381

RESUMO

Posttranslational modifications of nuclear proteins, including transcription factors, nuclear receptors, and their coregulators, have attracted much attention in cancer research. Although phosphorylation of oligodendrocyte transcription factor 2 (Olig2) may contribute to the notorious resistance of gliomas to radiation and genotoxic drugs, the precise mechanisms remain elusive. We show here that in addition to phosphorylation, Olig2 is also conjugated by small ubiquitin-like modifier-1 (SUMO1) at three lysine residues K27, K76, and K112. SUMOylation is required for Olig2 to suppress p53-mediated cell cycle arrest and apoptosis induced by genotoxic damage, and to enhance resistance to temozolomide (TMZ) in glioma. Both SUMOylation and triple serine motif (TSM) phosphorylation of Olig2 are required for the antiapoptotic function. Olig2 SUMOylation enhances its genetic targeting ability, which in turn occludes p53 recruitment to Cdkn1a promoter for DNA-damage responses. Our work uncovers a SUMOylation-dependent regulatory mechanism of Olig2 in regulating cancer survival.


Assuntos
Dano ao DNA , Glioma/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Sumoilação , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Pontos de Checagem do Ciclo Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Marcação de Genes , Glioma/genética , Glioma/patologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fator de Transcrição 2 de Oligodendrócitos/genética , Fosforilação , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Front Oncol ; 10: 502, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328466

RESUMO

Chordoid glioma (CG) of the third ventricle is a rare type of brain tumor. Here, we present a case, review of the literature and proposed a treatment strategy for this rare tumor. Here, A 33-years-old woman presented with the menstrual disorder and progressive obesity. Magnetic resonance imaging showed a large irregularly circular tumor in the third ventricle. The tumor was subtotally resected by microsurgery via the right modified port approach. Immunohistochemical staining was positive for glial fibrillary acidic protein (GFAP), Vimentin and transcription termination factor-1 (TTF-1), and the Ki-67 proliferation index was low (5%), which indicating CG. Residual tumor decreased after treated by Gamma Knife radiosurgery (GKRS) with a dose of 15 Gy. During 30 months of follow-up, the tumor did not recur, and the patient suffered no complications. The diagnosis of CG requires a combination of clinical presentation, neuroimaging, and pathology. The ideal therapy is gross total resection (GTR) of the tumor. However, GTR is usually difficult and carries a high risk of postoperative complications because of the tumor location. This case indicates that planed subtotal resection followed by GKRS with a proper marginal dose could be a good treatment strategy for CG.

8.
Brain Stimul ; 13(3): 643-649, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32289691

RESUMO

BACKGROUND: Given that anorexia nervosa (AN) is a life-threatening mental disorder and has poor clinical outcomes, novel effective treatments are warranted, especially for severe and persistent cases. OBJECTIVE: To investigate the safety, feasibility, and clinical outcomes of using deep brain stimulation (DBS) of the nucleus accumbens (NAcc) in treatment-refractory AN patients. METHODS: A total of 28 women with refractory AN underwent NAcc-DBS and completed this 2-year follow-up study. The clinical outcomes, including body mass index (BMI) and mood, anxiety, and obsessive symptoms, were assessed using a series of psychiatric scales at 6 and 24 months post operation. RESULTS: While no fatalities were reported during this study, 1 patient showed device rejection. The most common short-term side effect observed was varying degrees of pain at the incision sites (n = 22), which usually disappeared 3-4 days following the operation. No severe surgical adverse events were observed. Compared to presurgical levels, significant increases in BMI and improvement in psychiatric scale scores were noted during the 6-month follow-up and were maintained at the 2-year review. Finally, a post-hoc analysis revealed that the NAcc-DBS was less effective for weight restoration in patients with the binge-eating/purge subtype of AN than in those with the restricting subtype (R-AN). CONCLUSION: Our long-term follow-up study suggests that NAcc-DBS is safe and effective for improving the BMI and psychiatric symptoms of patients with refractory AN. Although NAcc-DBS appears to be more suitable for patients with R-AN, strict inclusion criteria must be applied considering surgery-related complications.


Assuntos
Anorexia Nervosa/diagnóstico por imagem , Anorexia Nervosa/terapia , Estimulação Encefálica Profunda/tendências , Núcleo Accumbens/diagnóstico por imagem , Adolescente , Adulto , Ansiedade/diagnóstico por imagem , Ansiedade/terapia , Estimulação Encefálica Profunda/métodos , Feminino , Seguimentos , Humanos , Resultado do Tratamento , Adulto Jovem
9.
J Neurol Sci ; 413: 116769, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32169741

RESUMO

PURPOSE: Glucocorticoid (GC) is probably related to biological aging, but the exact mechanism remains unknown. Cushing's disease (CD) could represent a unique human model for examining the effects of prolonged exposure to hypercortisolism and its relationship with aging. Thus, we studied the alterations of neurites in CD patients with Neurite orientation dispersion and density imaging (NODDI). METHODS: CD patients (n = 15) and healthy control subjects (n = 15) were included in this study. Orientation dispersion index (Odi), neurite density index (Ndi), partial fraction of free water (fiso), partial fraction of extracellular water (fec) were examined in a cross-sectional analysis. RESULTS: Significant altered NODDI parameters were found in CD patients. Some of these alterations were correlated with current age. Additionally, increased dendritic density was found in cerebellar of CD patients. CONCLUSION: Hypercortisolism relative reductions of the dendritic density were correlated with current age in several regions of CD patients. Our study enhances the understanding of the link between the aging and GC.


Assuntos
Neuritos , Hipersecreção Hipofisária de ACTH , Envelhecimento , Encéfalo , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Hipersecreção Hipofisária de ACTH/diagnóstico por imagem
10.
Transl Neurodegener ; 8: 32, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827782

RESUMO

BACKGROUND: CSF1R-related leukoencephalopathy, also known as hereditary diffuse leukoencephalopathy with spheroids (HDLS), is a rare white-matter encephalopathy characterized by motor and neuropsychiatric symptoms due to colony-stimulating factor 1 receptor (CSF1R) gene mutation. Few of CSF1R mutations have been functionally testified and the pathogenesis remains unknown. METHODS: In order to investigate clinical and pathological characteristics of patients with CSF1R-related leukoencephalopathy and explore the potential impact of CSF1R mutations, we analyzed clinical manifestations of 15 patients from 10 unrelated families and performed brain biopsy in 2 cases. Next generation sequencing was conducted for 10 probands to confirm the diagnosis. Sanger sequencing, segregation analysis and phenotypic reevaluation were utilized to substantiate findings. Functional examination of identified mutations was further explored. RESULTS: Clinical and neuroimaging characteristics were summarized. The average age at onset was 35.9 ± 6.4 years (range 24-46 years old). Younger age of onset was observed in female than male (34.2 vs. 39.2 years). The most common initial symptoms were speech dysfunction, cognitive decline and parkinsonian symptoms. One patient also had marked peripheral neuropathy. Brain biopsy of two cases showed typical pathological changes, including myelin loss, axonal spheroids, phosphorylated neurofilament and activated macrophages. Electron microscopy disclosed increased mitochondrial vacuolation and disorganized neurofilaments in ballooned axons. A total of 7 pathogenic variants (4 novel, 3 documented) were identified with autophosphorylation deficiency, among which c.2342C > T remained partial function of autophosphorylation. Western blotting disclosed the significantly lower level of c.2026C > T (p.R676*) than wild type. The level of microtubule associated protein 1 light chain 3-II (LC3-II), a classical marker of autophagy, was significantly lower in mutants expressed cells than wild type group by western blotting and immunofluorescence staining. CONCLUSIONS: Our findings support the loss-of-function and haploinsufficiency hypothesis in pathogenesis. Autophagy abnormality may play a role in the disease. Repairing or promoting the phosphorylation level of mutant CSF1R may shed light on therapeutic targets in the future. However, whether peripheral polyneuropathy potentially belongs to CSF1R-related spectrum deserves further study with longer follow-up and more patients enrolled. TRIAL REGISTRATION: ChiCTR, ChiCTR1800015295. Registered 21 March 2018.

11.
Cell Death Dis ; 10(11): 866, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727877

RESUMO

Long non-coding RNA THOR (Lnc-THOR) binds to IGF2BP1, essential for its function. We here show that Lnc-THOR is expressed in human glioma tissues and cells. Its expression is extremely low or even undetected in normal brain tissues, as well as in human neuronal cells and astrocytes. We show that Lnc-THOR directly binds to IGF2BP1 in established and primary human glioma cells. shRNA-mediated Lnc-THOR knockdown or CRISPR/Cas9-induced Lnc-THOR knockout potently inhibited cell survival and proliferation, while provoking glioma cell apoptosis. Contrarily, forced overexpression of Lnc-THOR promoted glioma cell growth and migration. Importantly, Lnc-THOR shRNA or knockout activated MAGEA6-AMPK signaling in glioma cells. AMPK inactivation, by AMPKα1 shRNA, knockout, or dominant-negative mutation (T172A), attenuated Lnc-THOR shRNA-induced A172 glioma cell apoptosis. Moreover, CRISPR/Cas9-induced IGF2BP1 knockout activated MAGEA6-AMPK signaling as well, causing A172 glioma cell apoptosis. Significantly, Lnc-THOR shRNA was ineffective in IGF2BP1 KO A172 cells. In vivo, Lnc-THOR silencing or knockout potently inhibited subcutaneous A172 xenograft tumor growth in mice. MAGEA6 downregulation and AMPK activation were detected in Lnc-THOR-silenced/-KO A172 tumor tissues. Taken together, Lnc-THOR depletion inhibits human glioma cell survival possibly by activating MAGEA6-AMPK signaling.


Assuntos
Antígenos de Neoplasias/genética , Glioma/genética , Proteínas de Neoplasias/genética , Proteínas Quinases/genética , RNA Longo não Codificante/genética , Quinases Proteína-Quinases Ativadas por AMP , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , Camundongos , RNA Interferente Pequeno , Proteínas de Ligação a RNA/genética , Transdução de Sinais/genética
12.
Steroids ; 151: 108457, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31326450

RESUMO

The adverse effects of hypercortisolism on the human brain have been highlighted in previous studies of Cushing's disease (CD). However, the reversibility of brain damage after the resolution of hypercortisolism remains unclear. Thus, we studied the potential volumetric reversibility in biochemically remitted CD patients. Cross-sectional analysis demonstrated the active CD patients (n = 61) had the smallest gray matter (GM) volumes (553.33 ±â€¯45.90 CM3) among four groups. While the GM volumes of short-term remitted CD patients (586.62 ±â€¯46.89 CM3, n = 28) and long-term remitted CD patients (596.58 ±â€¯45.95 CM3, n = 35) were between those of the active CD patients and healthy control subjects (628.14 ±â€¯46.88 CM3, n = 74). Moreover, significant positive correlations between remitted time and GM volumes were only found in short-term remitted CD patients. On the contrary, the alterations of white matter (WM) in CD patients seem to be independent of concomitant hypercortisolism, persisting after remission. A preliminary longitude analysis also demonstrated similar results. Volumetric reversibility of GM, but not WM is highly prevalent in short-term after resolution of hypercortisolism in Cushing disease. Our study enhances our understanding of the reversible and the irreversible structural alterations in the human brain due to hypercortisolism.


Assuntos
Encéfalo/patologia , Síndrome de Cushing/patologia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos Transversais , Síndrome de Cushing/diagnóstico por imagem , Síndrome de Cushing/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
13.
Int J Oncol ; 52(6): 1934-1946, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29620167

RESUMO

Cushing's disease is primarily caused by pituitary adrenocorticotropin­secreting adenoma. However, its pathogenesis has remained obscure. In the present study, whole transcriptome analysis was performed by RNA sequencing (RNA­Seq) and expression of secreted frizzled­related protein 2 (SFRP2) was decreased in corticotroph tumors compared with normal pituitary glands. Furthermore, the RNA­Seq results were validated and the expression of SFRP2 in tumor tissues was analyzed by comparing another cohort of 23 patients with Cushing's disease and 3 normal human pituitary samples using reverse transcription­quantitative polymerase chain reaction, western blot and immunohistochemistry staining. Clinically, there was an association between lower SFRP2 expression and aggressive adenoma characteristics, including larger size and invasiveness. Conversely, SFRP2 overexpression reduced the ability of AtT20 cells to proliferate and migrate, and reduced production of the adrenocorticotrophic hormone in vitro. Mechanistically, overexpressed SFRP2 reduced the level of ß­catenin in the cytoplasm and nucleus, and decreased Wnt signaling activity in AtT20 cells. Therefore, SFRP2 appears to act as a tumor suppressor in Cushing's disease by regulating the activity of the Wnt signaling pathway.


Assuntos
Adenoma Hipofisário Secretor de ACT/patologia , Adenoma/patologia , Regulação para Baixo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Via de Sinalização Wnt , Adenoma Hipofisário Secretor de ACT/genética , Adenoma Hipofisário Secretor de ACT/metabolismo , Adenoma/genética , Adenoma/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Análise de Sequência de RNA/métodos , Carga Tumoral , Adulto Jovem
14.
Biochem Biophys Res Commun ; 496(2): 712-718, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29360452

RESUMO

The long non-coding RNA SNHG7 (small nucleolar RNA host gene 7) has been reported to be involved in various cancers as a potential oncogene. However, the functions and molecular mechanisms of SNHG7 in glioblastoma (GBM) are largely unknown. In the present study, we showed that the expression of SNHG7 was significantly upregulated in GBM tissues and cell lines compared with non-cancerous brain tissues. Furthermore, we found that SNHG7 knockdown remarkably suppressed the proliferation, migration and invasion of A172 and U87 cells while inducing their apoptosis. Subsequently, we showed that SNHG7 knockdown significantly inhibited tumor growth and metastasis in vivo by using xenograft experiments in nude mice. In terms of mechanism, we found that SNHG7 directly inhibited miR-5095, which targeted the 3' UTR of CTNNB1 mRNA and subsequently downregulated the Wnt/ß-catenin signaling pathway in GBM. Using rescue experiments, we demonstrated that SNHG7 promoted the proliferation, migration and invasion of GBM cells through the inhibition of miR-5095 and concomitant activation of Wnt/ß-catenin signaling pathway. Taken together, the SNHG7/miR-5095 axis might be a potential target for the development of effective GBM therapy.


Assuntos
Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Animais , Apoptose , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Glioblastoma/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus
15.
Cancer Lett ; 412: 21-29, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29024810

RESUMO

Melanoma antigen A6 (MAGEA6)/TRIM28 complex is a cancer-specific ubiquitin ligase, which degradates tumor suppressor protein AMP-activated protein kinase (AMPK). We show that MAGEA6 is uniquely expressed in human glioma tissues and cells, which is correlated with AMPKα1 downregulation. It is yet absent in normal brain tissues and human astrocytes/neuronal cells. MAGEA6 knockdown by targeted-shRNA in glioma cells restored AMPKα1 expression, causing mTORC1 in-activation and cell death/apoptosis. Reversely, AMPKα1 knockdown or mutation ameliorated glioma cell death by MAGEA6 shRNA. In vivo, Glioma xenograft tumor growth in mice was largely inhibited following expressing MAGEA6 shRNA. AMPKα1 upregulation and mTORC1 inhibition were observed in MAGEA6 shRNA-bearing xenograft tissues. Collectively, MAGEA6 promotes glioma cell survival possibly via targeting AMPKα1.


Assuntos
Proteínas Quinases Ativadas por AMP/fisiologia , Antígenos de Neoplasias/fisiologia , Glioma/patologia , Proteínas de Neoplasias/fisiologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Idoso , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Interferente Pequeno/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Clin Endocrinol (Oxf) ; 87(4): 367-374, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28543178

RESUMO

OBJECTIVE: The data on patients with short-term remission of Cushing's disease (CD) might provide information that is not available from previous long-term remission studies. We aimed to investigate structural changes in the brain in these patients and to examine whether these changes were associated with clinical characteristics. DESIGN: A cross-sectional study was performed. METHODS: Thirty-four patients with CD (14 with CD in short-term remission and 20 with active CD) and 34 controls matched for age, sex and education underwent clinical evaluation and magnetic resonance imaging brain scans. Biometric measurements, disease duration and remission duration data were collected. Grey matter volumes in the whole brain were examined using voxel-based morphometry (VBM). RESULTS: No differences were observed in the grey matter volumes of the medial frontal gyrus (MFG) and cerebellum between the patients with remitted CD and healthy controls, whereas patients with active CD had smaller grey matter volumes in these two regions compared with controls and patients with remitted CD. Furthermore, significant correlations were found between remission time and grey matter values in these regions in short-term remission patients with CD. Additionally, greater grey matter volumes in the bilateral caudate of short-term remission patients with CD were observed. CONCLUSIONS: Trends for structural restoration were found in CD patients with short-term remission. This finding was associated with the number of days elapsed since curative surgery and the current age of the patients. This study enhances our understanding of potential reversibility after the resolution of hypercortisolism in CD patients.


Assuntos
Imageamento por Ressonância Magnética/métodos , Hipersecreção Hipofisária de ACTH/diagnóstico por imagem , Hipersecreção Hipofisária de ACTH/patologia , Adulto , Estudos Transversais , Síndrome de Cushing/diagnóstico por imagem , Síndrome de Cushing/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/patologia , Adulto Jovem
17.
Brain Res ; 1665: 80-87, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28438531

RESUMO

Exposure to chronic hypercortisolism has multiple adverse effects on brain biology in humans. Cushing's disease (CD) represents a unique and natural human model for examining the effects of hypercortisolism on the brain. This cross-sectional study used Diffusional Kurtosis Imaging (DKI) to investigate the microstructure alterations in both white matter (WM) and gray matter (GM) of CD patients and to determine the relationship of these changes with clinical characteristics. DKI images were obtained from 15 active CD patients. DKI parametric maps were estimated through voxel-based analyses (VBA) and compared with 15 healthy controls matched for age, sex and education. In addition, correlations were analyzed between the altered DKI parameters and clinical characteristics. Compared with healthy controls, CD patients mainly exhibited significantly altered diffuse parameters in the GM and WM of the left medial temporal lobe (MTL). The mean values of increased radial diffusivity (RD) of CD patients in GM of the left hippocampus/parahippocampal gyrus correlated positively with the clinical severity of CD. Additionally, we also found altered kurtosis parameters in the cerebellum and frontal lobe. DKI imaging of CD patients could represent complementary information in both white matter and gray matter. The impairment of the left MTL might explain some part of the memory and cognition impairments in CD patients.


Assuntos
Substância Cinzenta/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Algoritmos , Disfunção Cognitiva/diagnóstico , Estudos Transversais , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade
18.
Clin Endocrinol (Oxf) ; 86(3): 367-376, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27859451

RESUMO

CONTEXT AND OBJECTIVE: Cushing's disease (CD) provides a unique and naturalist model for studying the influence of hypercortisolism on the human brain and the reversibility of these effects after resolution of the condition. This cross-sectional study used resting-state fMRI (rs-fMRI) to investigate the altered spontaneous brain activity in CD patients and the trends for potential reversibility after the resolution of the hypercortisolism. We also aim to determine the relationship of these changes with clinical characteristics and cortisol levels. SUBJECTS AND METHODS: Active CD patients (n = 18), remitted CD patients (n = 14) and healthy control subjects (n = 22) were included in this study. Amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) values were calculated to represent spontaneous brain activity. RESULTS: Our study resulted in three major findings: (i) active CD patients showed significantly altered spontaneous brain activity in the posterior cingulate cortex (PCC)/precuneus (PCu), occipital lobe (OC)/cerebellum, thalamus, right postcentral gyrus (PoCG) and left prefrontal cortex (PFC); (ii) trends for partial restoration of altered spontaneous brain activity after the resolution hypercortisolism were found in several brain regions; and (iii) active CD patients showed a significant correlation between cortisol levels and ALFF/ReHo values in the PCC/PCu, a small cluster in the OC and the right IPL. CONCLUSIONS: This study provides a new approach to investigating brain function abnormalities in patients with CD and enhances our understanding of the effect of hypercortisolism on the human brain. Furthermore, our explorative potential reversibility study of patients with CD may facilitate the development of future longitudinal studies.


Assuntos
Encéfalo/fisiopatologia , Hipersecreção Hipofisária de ACTH/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Estudos Transversais , Síndrome de Cushing/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Hipersecreção Hipofisária de ACTH/diagnóstico por imagem , Adulto Jovem
19.
PLoS One ; 11(8): e0161017, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27532105

RESUMO

Here, we studied the anti-glioma cell activity by a novel AMP-activated protein kinase (AMPK) activator GSK621. We showed that GSK621 was cytotoxic to human glioma cells (U87MG and U251MG lines), possibly via provoking caspase-dependent apoptotic cell death. Its cytotoxicity was alleviated by caspase inhibitors. GSK621 activated AMPK to inhibit mammalian target of rapamycin (mTOR) and downregulate Tetraspanin 8 (Tspan8) in glioma cells. AMPK inhibition, through shRNA knockdown of AMPKα or introduction of a dominant negative (T172A) AMPKα, almost reversed GSK621-induced AMPK activation, mTOR inhibition and Tspan8 degradation. Consequently, GSK621's cytotoxicity in glioma cells was also significantly attenuated by AMPKα knockdown or mutation. Further studies showed that GSK621, at a relatively low concentration, significantly potentiated temozolomide (TMZ)'s sensitivity and lethality against glioma cells. We summarized that GSK621 inhibits human glioma cells possibly via activating AMPK signaling. This novel AMPK activator could be a novel and promising anti-glioma cell agent.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/enzimologia , Glioma/tratamento farmacológico , Glioma/enzimologia , Imidazóis/farmacologia , Pirimidinonas/farmacologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos , Imidazóis/administração & dosagem , Pirimidinonas/administração & dosagem , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Temozolomida , Tetraspaninas/metabolismo
20.
Oncotarget ; 7(8): 9175-87, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26824322

RESUMO

Cushing's disease is caused by pituitary corticotroph adenoma, and the pathogenesis of it has remained obscure. Here, we showed that cold inducible RNA binding protein (CIRP) was markedly elevated in corticotroph tumors. Forced overexpression of CIRP in murine AtT20 pituitary corticotroph cell line increased corticotroph precursor hormone proopiomelanocortin (POMC) transcription, ACTH secretion and cellular proliferation. In vivo, CIRP overexpression promotes murine corticotroph tumor growth and enhances ACTH production. Mechanistically, we show that CIRP could promote AtT20 cells proliferation by inducing cyclinD1 and decreasing p27 expression via Erk1/2 signaling pathway. Clinically, CIRP overexpression is significantly correlated with Cushing's disease recurrence. CIRP appears to play a critical tumorigenesis function in Cushing's disease and its expression might be a useful biomarker for tumor recurrence.


Assuntos
Adenoma Hipofisário Secretor de ACT/patologia , Corticotrofos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Hipersecreção Hipofisária de ACTH/patologia , Proteínas de Ligação a RNA/biossíntese , Adenoma/patologia , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/biossíntese , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Pró-Opiomelanocortina/genética , Antígeno Nuclear de Célula em Proliferação/biossíntese , Adulto Jovem
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