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Background: Cushing disease (CD) is a rare clinical neuroendocrine disease. CD is characterized by abnormal hypercortisolism induced by a pituitary adenoma with the secretion of adrenocorticotropic hormone. Individuals with CD usually exhibit atrophy of gray matter volume. However, little is known about the alterations in topographical organization of individuals with CD. This study aimed to investigate the structural covariance networks of individuals with CD based on the gray matter volume using graph theory analysis. Methods: High-resolution T1-weighted images of 61 individuals with CD and 53 healthy controls were obtained. Gray matter volume was estimated and the structural covariance network was analyzed using graph theory. Network properties such as hubs of all participants were calculated based on degree centrality. Results: No significant differences were observed between individuals with CD and healthy controls in terms of age, gender, and education level. The small-world features were conserved in individuals with CD but were higher than those in healthy controls. The individuals with CD showed higher global efficiency and modularity, suggesting higher integration and segregation as compared to healthy controls. The hub nodes of the individuals with CD were Short insular gyri (G_insular_short_L), Anterior part of the cingulate gyrus and sulcus (G_and_S_cingul-Ant_R), and Superior frontal gyrus (G_front_sup_R). Conclusions: Significant differences in the structural covariance network of patients with CD were found based on graph theory. These findings might help understanding the pathogenesis of individuals with CD and provide insight into the pathogenesis of this CD.
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Accurate navigation and targeting are critical for neurological interventions including biopsy and deep brain stimulation. Real-time image guidance further improves surgical planning and MRI is ideally suited for both pre- and intra-operative imaging. However, balancing spatial and temporal resolution is a major challenge for real-time interventional MRI (i-MRI). Here, we proposed a deep unrolled neural network, dubbed as LSFP-Net, for real-time i-MRI reconstruction. By integrating LSFP-Net and a custom-designed, MR-compatible interventional device into a 3 T MRI scanner, a real-time MRI-guided brain intervention system is proposed. The performance of the system was evaluated using phantom and cadaver studies. 2D/3D real-time i-MRI was achieved with temporal resolutions of 80/732.8 ms, latencies of 0.4/3.66 s including data communication, processing and reconstruction time, and in-plane spatial resolution of 1 × 1 mm2. The results demonstrated that the proposed method enables real-time monitoring of the remote-controlled brain intervention, and showed the potential to be readily integrated into diagnostic scanners for image-guided neurosurgery.
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Encéfalo , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Biópsia , Procedimentos Neurocirúrgicos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodosRESUMO
OBJECTIVE: Cushing disease (CD) is a rare clinical disease in which brain structural and function are impaired as the result of excessive cortisol. However, little is known whether rich-club organization changes in patients with CD, as visualized on resting-state magnetic resonance imaging (fMRI), can reverse to normal conditions after transsphenoidal surgery (TSS). In this study, we aimed to investigate whether the functional connectivity of rich-club organization is affected and whether any abnormal changes may reverse after TSS. METHODS: In this study, 38 patients with active CD, 33 with patients with CD in remission, and 41 age-, sex-, and education-matched healthy control participants underwent resting-state fMRI. Brain functional connectivity was constructed based on fMRI and rich club was calculated with graph theory approach. We constructed the functional brain networks for all participants and calculated rich-club connectivity based on fMRI. RESULTS: We identified left precuneus, right precuneus, left middle cingulum, right middle cingulum, right inferior temporal, right middle temporal, right lingual, right postcentral, right middle occipital, and right precentral regions as rich club nodes. Compared with healthy control participants, rich-club connectivity was significantly lower in patients with active CD (P < 0.001). Moreover, abnormal rich-club connectivity improved to normal after TSS. CONCLUSIONS: Our results show rich-club organization was disrupted in patients with active CD with excessive cortisol production. TSS can reverse abnormal rich-club connectivity. Rich club may be a new indicator to investigate the outcomes of TSS and to increase our understanding of the effect of excessive cortisol on brain functional connectivity in patients with CD.
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Adenoma Hipofisário Secretor de ACT/cirurgia , Conectoma , Substância Cinzenta/patologia , Hipersecreção Hipofisária de ACTH/fisiopatologia , Neoplasias Hipofisárias/cirurgia , Adenoma Hipofisário Secretor de ACT/complicações , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Hidrocortisona/sangue , Hipofisectomia/métodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Neuroimagem , Hipersecreção Hipofisária de ACTH/diagnóstico por imagem , Hipersecreção Hipofisária de ACTH/patologia , Hipersecreção Hipofisária de ACTH/cirurgia , Neoplasias Hipofisárias/complicações , Indução de Remissão , Osso Esfenoide/cirurgia , Adulto JovemRESUMO
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.
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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 XenoenxertoRESUMO
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.
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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 imagemRESUMO
To investigate the whole functional brain networks of active Cushing disease (CD) patients about topological parameters (small world and rich club et al.) and compared with healthy control (NC). Nineteen active CD patients and twenty-two healthy control subjects, matched in age, gender, and education, underwent resting-state fMRI. Graph theoretical analysis was used to calculate the functional brain network organizations for all participants, and those for active CD patients were compared for and NCs. Active CD patients revealed higher global efficiency, shortest path length and reduced cluster efficiency compared with healthy control. Additionally, small world organization was present in active CD patients but higher than healthy control. Moreover, rich club connections, feeder connections and local connections were significantly decreased in active CD patients. Functional network properties appeared to be disrupted in active CD patients compared with healthy control. Analyzing the changes that lead to abnormal network metrics will improve our understanding of the pathophysiological mechanisms underlying CD.
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Encéfalo/fisiopatologia , Rede Nervosa/fisiopatologia , Hipersecreção Hipofisária de ACTH/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
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.
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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/genéticaRESUMO
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 (nâ¯=â¯61) had the smallest gray matter (GM) volumes (553.33⯱â¯45.90â¯CM3) among four groups. While the GM volumes of short-term remitted CD patients (586.62⯱â¯46.89â¯CM3, nâ¯=â¯28) and long-term remitted CD patients (596.58⯱â¯45.95â¯CM3, nâ¯=â¯35) were between those of the active CD patients and healthy control subjects (628.14⯱â¯46.88â¯CM3, nâ¯=â¯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.
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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 , MasculinoRESUMO
Objective: To summarize the characteristics of patients with pituitary stalk thickening, analyze the association between pituitary stalk width and hypopituitarism, and develop a diagnostic model to differentiate neoplastic and inflammatory origins. Methods: A total of 325 patients with pituitary stalk thickening in a tertiary teaching hospital between January 2012 and February 2018 were enrolled. Basic characteristics and hormonal status were evaluated. Indicators to predict etiology in patients with histologic diagnoses were analyzed. Results: Of the 325 patients, 62.5% were female. Deficiency in gonadotropin was most common, followed by corticotropin, growth hormone, and thyrotropin. The increase in pituitary stalk width was associated with a risk of central diabetes insipidus (odds ratio [OR], 3.57; P<.001) and with a combination of central diabetes insipidus and anterior pituitary deficiency (OR, 2.28; P = .029). The cut-off pituitary stalk width of 4.75 mm had a sensitivity of 69.2% and a specificity of 71.4% for the presence of central diabetes insipidus together with anterior pituitary deficiency. Six indicators (central diabetes insipidus, pattern of pituitary stalk thickening, pituitary stalk width, neutrophilic granulocyte percentage, serum sodium level, and gender) were used to develop a model having an accuracy of 95.7% to differentiate neoplastic from inflammatory causes. Conclusion: Pituitary stalk width could indicate the presence of anterior pituitary dysfunction, especially in central diabetes insipidus patients. With the use of a diagnostic model, the neoplastic and inflammatory causes of pituitary stalk thickening could be preliminarily differentiated. Abbreviations: APD = anterior pituitary dysfunction; AUC = area under the curve; CDI = central diabetes insipidus; GH = growth hormone; MRI = magnetic resonance imaging; OR = odd ratio; PHBS = posterior hypophyseal bright spots; PST = pituitary stalk thickening; PSW = pituitary stalk width.
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Diabetes Insípido Neurogênico , Hipopituitarismo , Doenças da Hipófise , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , HipófiseRESUMO
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.
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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 XenoenxertoRESUMO
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.
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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 JovemRESUMO
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.
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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-IdadeRESUMO
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.
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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 JovemRESUMO
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.
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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/metabolismoRESUMO
BACKGROUND: Two recent whole-exome sequencing researches identifying somatic mutations in the ubiquitin-specific protease 8 (USP8) gene in pituitary corticotroph adenomas provide exciting advances in this field. These mutations drive increased epidermal growth factor receptor (EGFR) signaling and promote adrenocorticotropic hormone (ACTH) production. This study was to investigate whether the inhibition of USP8 activity could be a strategy for the treatment of Cushing's disease (CD). METHODS: The anticancer effect of USP8 inhibitor was determined by testing cell viability, colony formation, apoptosis, and ACTH secretion. The immunoblotting and quantitative reverse transcription polymerase chain reaction were conducted to explore the signaling pathway by USP8 inhibition. RESULTS: Inhibition of USP8-induced degradation of receptor tyrosine kinases including EGFR, EGFR-2 (ERBB2), and Met leading to a suppression of AtT20 cell growth and ACTH secretion. Moreover, treatment with USP8 inhibitor markedly induced AtT20 cells apoptosis. CONCLUSIONS: Inhibition of USP8 activity could be an effective strategy for CD. It might provide a novel pharmacological approach for the treatment of CD.
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Hormônio Adrenocorticotrópico/metabolismo , Endopeptidases/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/antagonistas & inibidores , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ubiquitina Tiolesterase/antagonistas & inibidores , Ubiquitina Tiolesterase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Inibidores Enzimáticos/farmacologia , Receptores ErbB/metabolismo , Humanos , Indenos/farmacologia , Camundongos , Pirazinas/farmacologiaRESUMO
AIM: Carvacrol (2-methyl-5-isopropylphenol), a phenolic monoterpene in the essential oils of the genera Origanum and Thymus, has been shown to exert a variety of therapeutic effects. Here we examined whether carvacrol protected neuroblastoma SH-SY5Y cells against Fe(2+)-induced apoptosis and explored the underlying mechanisms. METHODS: Neuroblastoma SH-SY5Y cells were incubated with Fe(2+) for 24 h, and the cell viability was assessed with CCK-8 assay. TUNEL assay and flow cytometric analysis were performed to evaluate cell apoptosis. The mRNA levels of pro-inflammatory cytokines and NF-κB p65 were determined using qPCR. The expression of relevant proteins was determined using Western blot analysis or immunofluorescence staining. RESULTS: Treatment of SH-SY5Y cells with Fe(2+) (50-200 µmol/L) dose-dependently decreased the cell viability, which was significantly attenuated by pretreatment with carvacrol (164 and 333 µmol/L). Treatment with Fe(2+) increased the Bax level and caspase-3 activity, and decreased the Bcl-2 level, resulting in cell apoptosis. Furthermore, treatment with Fe(2+) significantly increased the gene expression of IL-1ß, IL-6 and TNF-α, and induced the nuclear translocation of NF-κB. Treatment with Fe(2+) also significantly increased the phosphorylation of p38, ERK, JNK and IKK in the cells. Pretreatment with carvacrol significantly inhibited Fe(2+)-induced activation of NF-κB, expression of the pro-inflammatory cytokines, and cell apoptosis. Moreover, pretreatment with carvacrol inhibited Fe(2+)-induced phosphorylation of JNK and IKK, but not p38 and ERK in the cells. CONCLUSION: Carvacrol protects neuroblastoma SH-SY5Y cells against Fe(2+)-induced apoptosis, which may result from suppressing the MAPK/JNK-NF-κB signaling pathways.
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Apoptose/efeitos dos fármacos , Ferro/toxicidade , MAP Quinase Quinase 4/imunologia , Proteínas Quinases Ativadas por Mitógeno/imunologia , Monoterpenos/uso terapêutico , NF-kappa B/imunologia , Fármacos Neuroprotetores/uso terapêutico , Cátions Bivalentes/toxicidade , Linhagem Celular Tumoral , Cimenos , Humanos , Transdução de Sinais/efeitos dos fármacosRESUMO
The ubiquitin-protein ligase E3C (UBE3C) belongs to the E3 ligase enzyme family and implicates in the ubiquitin-proteasome pathway, thus regulates physiological and cancer-related processes. Here, we investigated the expression and roles of UBE3C in glioma. We demonstrated that UBE3C was overexpressed in glioma tissues and cell lines. Inhibition of UBE3C expression in glioma cells significantly decreased cell migration and invasion in vitro. Mechanistically, we disclosed that UBE3C physically interacted with and ubiquitinated tumor suppressor gene annexin A7 (ANXA7), resulting in ubiquitination and degradation of ANXA7. Our results also revealed that increased UBE3C expression was accompanied by a reduction in ANXA7 protein expression in glioma tissues, but not ANXA7 mRNA. Importantly, the inhibition of ANXA7 expression in gliomas cells with UBE3C interference could rescue the cell invasion. Clinically, UBE3C overexpression significantly correlated with high-grade tumors (p < 0.05), poor overall survival, and early tumor recurrence. Thus, our data reveal that high UBE3C expression contributes to glioma progression by ubiquitination and degradation of ANXA7, and thus presents a novel and promising target for glioma therapy.
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Anexina A7/metabolismo , Glioma/metabolismo , Proteólise , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitinação , Anexina A7/genética , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Humanos , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
AIM: Aquaporins (AQPs) are the water-channels that play important roles in brain water homeostasis and in cerebral edema induced by brain injury. In this study we investigated the relationship between AQPs and a neuroprotective agent curcumin that was effective in the treatment of brain edema in mice with intracerebral hemorrhage (ICH). METHODS: ICH was induced in mice by autologous blood infusion. The mice immediately received curcumin (75, 150, 300 mg/kg, ip). The Rotarod test scores, brain water content and brain expression of AQPs were measured post ICH. Cultured primary mouse astrocytes were used for in vitro experiments. The expression of AQP1, AQP4 and AQP9 and NF-κB p65 were detected using Western blotting or immunochemistry staining. RESULTS: Curcumin administration dose-dependently reduced the cerebral edema at d 3 post ICH, and significantly attenuated the neurological deficits at d 5 post ICH. Furthermore, curcumin dose-dependently decreased the gene and protein expression of AQP4 and AQP9, but not AQP1 post ICH. Treatment of the cultured astrocytes with Fe(2+) (10-100 µmol/L) dose-dependently increased the expression and nuclear translocation of NF-κB p65 and the expression of AQP4 and AQP9, which were partly blocked by co-treatment with curcumin (20 µmol/L) or the NF-κB inhibitor PDTC (10 µmol/L). CONCLUSION: Curcumin effectively attenuates brain edema in mice with ICH through inhibition of the NF-κB pathway and subsequently the expression of AQP4 and AQP9. Curcumin may serve as a potential therapeutic agent for ICH.
Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Aquaporina 4/genética , Aquaporinas/genética , Edema Encefálico/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Curcumina/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Animais , Aquaporina 4/análise , Aquaporinas/análise , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Astrócitos/metabolismo , Astrócitos/patologia , Encéfalo/imunologia , Encéfalo/metabolismo , Encéfalo/patologia , Edema Encefálico/genética , Edema Encefálico/imunologia , Edema Encefálico/patologia , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/imunologiaRESUMO
The malignant glioma remains one of the most aggressive human malignancies with extremely poor prognosis. Glioma cell invasion and migration are the main causes of death. In the current study, we studied the expression and the potential functions of tetraspanin 8 (Tspan8) in malignant gliomas. We found that Tspan8 expression level is high in both malignant glioma tissues and in several human glioma cell lines, where it formed a complex integrin α3 and rictor, the latter is a key component of mammalian target of rapamycin (mTOR) complex 2 (mTORC2). Disruption of this complex, through siRNA-mediated knockdown of anyone of these three proteins, inhibited U251MG glioma cell migration in vitro. We further showed that Tspan8-rictor association appeared required for mTORC2 activation. Knockdown of Tspan8 by the targeted siRNAs prevented mTOR-rictor (mTORC2) assembly as well as phosphorylation of AKT (Ser-473) and protein kinase C α (PKCα) in U251MG cells. Together, these results demonstrate that over-expressed Tspan8 in malignant glioma forms a complex with rictor and integrin α3 to mediate mTORC2 activation and glioma cell migration. Therefore, targeting Tspan8-rictor-integrin α3 complex may provide a potential therapeutic intervention for malignant glioma.
Assuntos
Proteínas de Transporte/metabolismo , Movimento Celular , Glioma/metabolismo , Integrina alfa3/metabolismo , Tetraspaninas/metabolismo , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Glioma/patologia , Humanos , Integrina alfa3/genética , Alvo Mecanístico do Complexo 2 de Rapamicina , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Ligação Proteica , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Tetraspaninas/genéticaRESUMO
Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma.