RESUMO
Our objective was to study NMR relaxometry of glioma invasion/migration at very low field (<2 mT) by fast-field-cycling NMR (FFC-NMR) and to decipher the pathophysiological processes of glioma that are responsible for relaxation changes in order to open a new diagnostic method that can be extended to imaging. The phenotypes of two new glioma mouse models, Glio6 and Glio96, were characterized by T2w -MRI, HE histology, Ki-67 immunohistochemistry (IHC) and CXCR4 RT-qPCR, and were compared with the U87 model. R1 dispersions of glioma tissues were acquired at low field (0.1 mT-0.8 T) ex vivo and were fitted with Lorentzian and power-law models to extract FFC biomarkers related to the molecular dynamics of water. In order to decipher relaxation changes, three main invasion/migration pathophysiological processes were studied: hypoxia, H2 O2 function and the water-channel aquaporin-4 (AQP4). Glio6 and Glio96 were characterized with invasion/migration phenotype and U87 with high cell proliferation as a solid glioma. At very low field, invasion/migration versus proliferation was characterized by a decrease in the relaxation-rate constant (ΔR1 ≈ -32% at 0.1 mT) and correlation time (≈-40%). These decreases corroborated the AQP4-IHC overexpression (Glio6/Glio96: +92%/+46%), suggesting rapid transcytolemmal water exchange, which was confirmed by the intracellular water-lifetime τIN decrease (ΔτIN ≈ -30%). In functional experiments, AQP4 expression, τIN and the relaxation-rate constant at very low field were all found to be sensitive to hypoxia and to H2 O2 stimuli. At very low field the role of water exchanges in relaxation modulation was confirmed, and for the first time it was linked to the glioma invasion/migration and to its main pathophysiological processes: hypoxia, H2 O2 redox signaling and AQP4 expression. The method appears appropriate to evaluate the effect of drugs that can target these pathophysiological mechanisms. Finally, FFC-NMR operating at low field is demonstrated to be sensitive to invasion glioma phenotype and can be straightforwardly extended to FFC-MRI as a new cancer invasion imaging method in the clinic.
Assuntos
Glioma , Água , Animais , Biomarcadores , Movimento Celular , Glioma/patologia , Hipóxia , Campos Magnéticos , Imageamento por Ressonância Magnética/métodos , Camundongos , Simulação de Dinâmica MolecularRESUMO
PURPOSE: To determine whether duplication of the ARID1A gene is responsible for a new recognizable syndrome. METHODS: We describe four patients with a 1p36.11 microduplication involving ARID1A as identified by array-comparative genomic hybridization . We performed comparative transcriptomic analysis of patient-derived fibroblasts using RNA sequencing and evaluated the impact of ARID1A duplication on the cell cycle using fluorescence-activated cell sorting. Functional relationships between differentially expressed genes were investigated with ingenuity pathway analysis (IPA). RESULTS: Combining the genomic data, we defined a small (122 kb), minimally critical region that overlaps the full ARID1A gene. The four patients shared a strikingly similar phenotype that included intellectual disability and microcephaly. Transcriptomic analysis revealed the deregulated expression of several genes previously linked to microcephaly and developmental disorders as well as the involvement of signaling pathways relevant to microcephaly, among which the polo-like kinase (PLK) pathway was especially notable. Cell-cycle analysis of patient-derived fibroblasts showed a significant increase in the proportion of cells in G1 phase at the expense of G2-M cells. CONCLUSION: Our study reports a new microduplication syndrome involving the ARID1A gene. This work is the first step in clarifying the pathophysiological mechanism that links changes in the gene dosage of ARID1A with intellectual disability and microcephaly.Genet Med advance online publication 01 December 2016.
Assuntos
Cromossomos Humanos Par 1 , Duplicação Gênica , Deficiência Intelectual/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Criança , Proteínas de Ligação a DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , SíndromeRESUMO
Monitoring glioma cell infiltration in the brain is critical for diagnosis and therapy. Using a new glioma Glio6 mouse model derived from human stem cells we show how diffusion tensor imaging (DTI) may predict glioma cell migration/invasion. In vivo multiparametric MRI was performed at one, two and three months of Glio6 glioma growth (Glio6 (n = 6), sham (n = 3)). This longitudinal study reveals the existence of a time window to study glioma cell/migration/invasion selectively. Indeed, at two months only Glio6 cell invasion was detected, while tumor mass formation, edema, blood-brain barrier leakage and tumor angiogenesis were detected later, at three months. To robustly confirm the potential of DTI for detecting glioma cell migration/invasion, a microscopic 3D-DTI (80 µm isotropic spatial resolution) technique was developed and applied to fixed mouse brains (Glio6 (n = 6), sham (n = 3)). DTI changes were predominant in the corpus callosum (CC), a known path of cell migration. Fractional anisotropy (FA) and perpendicular diffusivity (D⥠) changes derived from ex vivo microscopic 3D-DTI were significant at two months of tumor growth. In the caudate putamen an FA increase of +38% (p < 0.001) was observed, while in the CC a - 28% decrease in FA (p < 0.005) and a + 95% increase in D⥠(p < 0.005) were observed. In the CC, DTI changes and fluorescent Glio6 cell density obtained by two-photon microscopy in the same brains were correlated (p < 0.001, r = 0.69), validating FA and D⥠as early quantitative biomarkers to detect glioma cell migration/invasion. The origin of DTI changes was assessed by electron microscopy of the same tract, showing axon bundle disorganization. During the first two months, Glio6 cells display a migratory phenotype without being associated with the constitution of a brain tumor mass. This offers a unique opportunity to apply microscopic 3D-DTI and to validate DTI parameters FA and D⥠as biomarkers for glioma cell invasion.
Assuntos
Neoplasias Encefálicas/patologia , Corpo Caloso/patologia , Imagem de Tensor de Difusão/métodos , Glioma/patologia , Imageamento Tridimensional/métodos , Imagem Multimodal/métodos , Células-Tronco Neoplásicas/patologia , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Linhagem Celular Tumoral , Movimento Celular , Rastreamento de Células/métodos , Corpo Caloso/diagnóstico por imagem , Feminino , Glioma/diagnóstico por imagem , Estudos Longitudinais , Camundongos , Camundongos Nus , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Invasividade Neoplásica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como AssuntoRESUMO
Most of our knowledge regarding glioma cell biology comes from cell culture experiments. For many years the standards for glioma cell culture were the use of cell lines cultured in the presence of serum and 20 % O2. However, in vivo, normoxia in many brain areas is in close to 3 % O2. Hence, in cell culture, the experimental value referred as the norm is hyperoxic compared to any brain physiological value. Likewise, cells in vivo are not usually exposed to serum, and low-passaged glioma neurosphere cultures maintained in serum-free medium is emerging as a new standard. A consequence of changing the experimental normoxic standard from 20 % O2 to the more brain physiological value of 3 % O2, is that a 3 % O2 normoxic reference point enabled a more rigorous characterization of the level of regulation of genes by hypoxia. Among the glioma hypoxia-regulated genes characterized using this approach we found VE-cadherin that is required for blood vessel formation, and filamin B a gene involved in endothelial cell motility. Both VE-cadherin and filamin B were found expressed in pseudopalisades, a glioblastoma pathognomonic structure made of hypoxic migrating cancer cells. These results provide additional clues on the role played by hypoxia in the acquisition of endothelial traits by glioma cells and on the functional links existing between pseudopalisades, hypoxia, and tumor progression.
Assuntos
Antígenos CD/metabolismo , Neoplasias Encefálicas/patologia , Caderinas/metabolismo , Endotélio Vascular/patologia , Filaminas/metabolismo , Glioma/patologia , Hipóxia/patologia , Antígenos CD/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Neoplasias Encefálicas/etiologia , Neoplasias Encefálicas/metabolismo , Caderinas/genética , Movimento Celular , Proliferação de Células , Endotélio Vascular/metabolismo , Filaminas/genética , Perfilação da Expressão Gênica , Glioma/etiologia , Glioma/metabolismo , Humanos , Hipóxia/complicações , Técnicas Imunoenzimáticas , Necrose , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais CultivadasRESUMO
OBJECTIVE: The roles of phosphatidylinositol 3 (PI3K) and mitogen-activated protein kinases (MAPK) have been widely studied in terms of the differentiation process induced by several drugs (phorbol ester, vitamin D-3, retinoic acid, etc.), but their exact functions in leukemic cells' phenotype and their potential therapeutic role remain incompletely clarified. MATERIALS AND METHODS: In order to investigate this query, leukemia cells were cultured in presence of kinase inhibitors (KIs). Proliferation, apoptosis, and differentiation were analyzed at the cellular and molecular levels, using flow cytometry and reverse transcriptase quantitative polymerase chain reaction. RESULTS: SB203580, a P38 MAPK inhibitor, had no effect on cell proliferation, whereas LY294002, a PI3K inhibitor, and PD098059, a selective inhibitor of mitogen-activated extracellular regulated kinase (MEK) phosphorylation, arrested cells in G(0)/G(1). However, LY294002 and PD098059 acted using different mechanisms: LY294002 decreased the expression of phosphorylated S6RP, whereas PD098059 increased P21/waf1 antigen expression. SP600125, an inhibitor of N-terminal c-jun kinases, arrested cells in G(2) and induced an endoreplicative process. SP600125 increased p21 at both the mRNA and protein levels. G(2) blockage is dependent on the PI3K pathway and the endoreplicative process is dependent on the PI3K and extracellular regulated kinase (ERK) pathways and mRNA synthesis. On the other hand, PD098059 potentiated the apoptotic process induced by either SP600125 or LY294002. Modulation of the expression of CD11, CD15, CD18, and CD54 was cell-dependent. CONCLUSION: Our results suggest that KIs modulate proliferation of leukemia cells and that the MEK/ERK inhibitor, PD098059, in combination with either SP600125 or LY294002, could have clinical value.
Assuntos
Leucemia/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Antracenos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/enzimologia , Cromonas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Flavonoides/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células HL-60/efeitos dos fármacos , Células HL-60/enzimologia , Humanos , Imidazóis/farmacologia , Leucemia/tratamento farmacológico , Leucemia/patologia , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , Morfolinas/farmacologia , Piridinas/farmacologia , Células U937/efeitos dos fármacos , Células U937/enzimologiaRESUMO
Cellular MRI, which visualizes magnetically labelled cells (cells*), is an active research field for in vivo cell therapy and tracking. The simultaneous relaxation rate measurements (R2 *, R2 , R1 ) are the basis of a quantitative cellular MRI method proposed here. U937 cells were labelled with Molday ION Rhodamine B, a bi-functional superparamagnetic and fluorescent nanoparticle (U937*). U937* viability and proliferation were not affected in vitro. In vitro relaxometry was performed in a cell concentration range of [2.5 × 104 -108 ] cells/mL. These measurements show the existence of complementary cell concentration intervals where these rates vary linearly. The juxtaposition of these intervals delineates a wide cell concentration range over which one of the relaxation rates in a voxel of an in vivo image can be converted into an absolute cell concentration. The linear regime was found at high concentrations for R1 in the range of [106 - 2 × 108 ] cells/mL, at intermediate concentrations for R2 in [2.5 × 105 - 5 × 107 ] cells/mL and at low concentrations for R2 * in [8 × 104 - 5 × 106 ] cells/mL. In vivo relaxometry was performed in a longitudinal study, with labelled U937 cells injected into a U87 glioma mouse model. Using in vitro data, maps of in vivo U937* concentrations were obtained by converting one of the in vivo relaxation rates to cell concentration maps. MRI results were compared with the corresponding optical images of the same brains, showing the usefulness of our method to accurately follow therapeutic cell biodistribution in a longitudinal study. Results also demonstrate that the method quantifies a large range of magnetically labelled cells*. Copyright © 2016 John Wiley & Sons, Ltd.
Assuntos
Transplante de Células , Imageamento por Ressonância Magnética/métodos , Animais , Encéfalo/patologia , Contagem de Células , Movimento Celular , Fluorescência , Glioma/patologia , Xenoenxertos , Humanos , Magnetismo , Camundongos , Células U937/transplanteRESUMO
PURPOSE: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. METHODS AND MATERIALS: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. RESULTS: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. CONCLUSIONS: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.
Assuntos
Neoplasias Encefálicas/radioterapia , Irradiação Craniana/métodos , Glioma/radioterapia , Hipofracionamento da Dose de Radiação , Radioterapia Conformacional/métodos , Síncrotrons/instrumentação , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Feminino , Glioma/patologia , Humanos , Masculino , Radioterapia de Alta Energia/instrumentação , Radioterapia de Alta Energia/métodos , Ratos , Ratos Endogâmicos F344 , Resultado do Tratamento , Carga Tumoral/efeitos da radiaçãoRESUMO
BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) or the internal segment of the globus pallidus (GPi) has been established as a highly effective symptomatic therapy for Parkinson's disease (PD). An intriguing biological aspect related to the DBS procedure is that a temporary contact establishes between surgical instruments and the surrounding brain tissue. In this exploratory study, we took advantage of this unique context to harvest brain material adhering to the stylet routinely used during surgery, and to examine the biological value of these samples, here referred to as "brain tissue imprints" (BTIs). RESULTS: Nineteen BTIs from 12 STN- or GPi-electrode implanted patients were obtained in vivo during DBS surgery, without any modification of the surgical procedure. Immunofluorescence analyses confirmed that our approach allowed the harvesting of many neural cells including neurons harboring distinct neurotransmitter markers. Shotgun proteomic and transcriptomic analyses provided for the first time molecular information from DBS-associated brain samples, and confirmed the compatibility of this new type of sample with poly-omic approaches. The method appears to be safe and results consistent. CONCLUSIONS: We here propose BTIs as original and highly valuable brain samples, and DBS-related brain imprinting as a new conceptual approach to biological research in living patients with PD.
Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson/terapia , Proteômica , Adulto , Idoso , Feminino , Globo Pálido , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/fisiologia , Núcleo SubtalâmicoRESUMO
1,25 Dihydroxyvitamin D3 (1,25D) is a hormone produced from vitamin D through two hydroxylating steps catalyzed successively in the liver by the vitamin D 25-hydroxylase Cyp2R1 and in the kidney by the 25-hydroxyvitamin D3 1α-hydroxylase Cyp27B1. 1,25D behaves like a steroid hormone. It regulates gene transcription by interacting with a nuclear receptor named vitamin D receptor (VDR) for the vitamin D receptor. Although the role of vitamin D is historically related to rickets, its physiological function largely encompasses bone tissues. Accumulating evidence has indicated that 1,25D can also be considered a neurosteroid. For example, both VDR and CYP27B1 are expressed in brain cells. Similarly, the neuroprotective and anti-inflammatory potential of 1,25D in nervous tissue has been shown experimentally. The regulation of Cyp27B1, which catalyzes the last step of 1,25D synthesis, by the inflammatory cytokines tumor necrosis factor-α and interferon-γ has been reported recently. However, the fate of Cyp2R1 that catalyzes the first enzymatic reaction of the vitamin D metabolism has not received attention. Using human brain pericytes, we studied the expression of CYP2R1 and VDR genes when these cells were challenged to an inflammatory stimulus. We found a significant upregulation of these two genes in human brain pericytes challenged with tumor necrosis factor-α and interferon-γ. These results suggest the existence of an autocrine/paracrine vitamin D system in the neurovascular unit. The function of this novel signaling system might be critical in the control of neuroinflammation and in brain pathologies.
Assuntos
Encéfalo/enzimologia , Colestanotriol 26-Mono-Oxigenase/genética , Pericitos/enzimologia , Receptores de Calcitriol/genética , Vitamina D/metabolismo , Comunicação Autócrina , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Família 2 do Citocromo P450 , Humanos , Interferon gama/farmacologia , Comunicação Parácrina , Pericitos/efeitos dos fármacos , Pericitos/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
BACKGROUND: Globozoospermia is a male infertility phenotype characterized by the presence in the ejaculate of near 100% acrosomeless round-headed spermatozoa with normal chromosomal content. Following intracytoplasmic sperm injection (ICSI) these spermatozoa give a poor fertilization rate and embryonic development. We showed previously that most patients have a 200 kb homozygous deletion, which includes DPY19L2 whole coding sequence. Furthermore we showed that the DPY19L2 protein is located in the inner nuclear membrane of spermatids during spermiogenesis and that it is necessary to anchor the acrosome to the nucleus thus performing a function similar to that realized by Sun proteins within the LINC-complex (Linker of Nucleoskeleton and Cytoskeleton). SUN1 was described to be necessary for gametogenesis and was shown to interact with the telomeres. It is therefore possible that Dpy19l2 could also interact, directly or indirectly, with the DNA and modulate gene expression during spermatogenesis. In this study, we compared the transcriptome of testes from Dpy19l2 knock out and wild type mice in order to identify a potential deregulation of transcripts that could explain the poor fertilization potential of Dpy19l2 mutated spermatozoa. METHODS: RNA was extracted from testes from DPY19L2 knock out and wild type mice. The transcriptome was carried out using GeneChip® Mouse Exon 1.0 ST Arrays. The biological processes and molecular functions of the differentially regulated genes were analyzed with the PANTHER software. RESULTS: A total of 76 genes were deregulated, 70 were up-regulated and 6 (including Dpy19l2) were down-regulated. These genes were found to be involved in DNA/RNA binding, structural organization, transport and catalytic activity. CONCLUSIONS: We describe that an important number of genes are differentially expressed in Dpy19l2 mice. This work could help improving our understanding of Dpy19l2 functions and lead to a better comprehension of the molecular mechanism involved in spermatogenesis.
CONTEXTE: La globozoospermie est caractérisée par la présence dans l'éjaculat de près de 100% de spermatozoïdes ronds et dépourvus d'acrosome qui présentent un contenu chromosomique normal. L'injection intracytoplasmique (ICSI) de ces spermatozoïdes donne cependant un taux de fécondation et de développement embryonnaire particulièrement bas. Nous avons montré précédemment que la plupart des patients globozoospermes présentent une délétion homozygote de 200 Kb qui inclue la totalité de la séquence codante du gène DPY19L2. De plus nous avons montré que la protéine DPY19L2 était localisée dans la membrane interne des noyaux des spermatides pendant la spermatogénèse et qu'elle est nécessaire pour fixer l'acrosome au noyau, réalisant ainsi une fonction similaire à celle des protéines Sun au sein du complexe LINC (Linker of Nucleoskeleton and Cytoskeleton). Il a par ailleurs été montré que SUN1 était nécessaire à la spermatogénèse et que cette protéine interagit avec les télomères chromosomiques. Il est donc possible que Dpy19l2 interagisse également, directement ou indirectement avec l'ADN et module l'expression génique lors de la spermatogénèse. Dans cette étude nous avons donc comparé le transcriptome de testicules de souris invalidées (KO) pour le gène Dpy19l2 à celui de souris sauvage afin d'identifier une éventuelle dérégulation génique qui pourrait expliquer le faible potentiel reproductif des spermatozoïdes globozoocéphales. MÉTHODE: L'ARN a été extrait de testicules de souris KO pour Dpy19l2 et de souris sauvages. Le transcriptome a été réalisé en utilisant des puces d'expression ® Mouse Exon 1.0 ST Arrays. Les processus biologiques et les fonctions des gènes dérégulés ont été analysés en utilisant le logiciel PANTHER. RÉSULTATS: Un total de 76 gènes a été identifié comme étant dérégulés, 70 gènes étaient surexprimés et 6 (incluant Dpy19l2) étaient sous-exprimés. Il s'agit de gènes principalement impliqués dans des interactions avec des acides nucléiques (ADN/ARN), ou ayant un rôle structural, dans le transport, ou présentant une activité catalytique. CONCLUSIONS: Cette étude nous a permis d'identifier et de décrire un nombre important de gènes exprimés de manière différentielle chez les souris KO pour Dpy19l2. Ce travail peut permettre d'améliorer notre compréhension des fonctions de Dpy19l2 et peut contribuer à obtenir une meilleure compréhension des mécanismes moléculaires nécessaire à la spermatogénèse.
RESUMO
Seasonal or chronic vitamin D deficiency and/or insufficiency is highly prevalent in the human population. Receptors for 1,25-dihydroxyvitamin D3, the hormonal metabolite of vitamin D, are found throughout the brain. To provide further information on the role of this hormone on brain function, we analyzed the transcriptomic profiles of mixed neuron-glial cell cultures in response to 1,25-dihydroxyvitamin D3. 1,25-dihydroxyvitamin D3 treatment increases the mRNA levels of 27 genes by at least 1.9 fold. Among them, 17 genes were related to neurodegenerative and psychiatric diseases, or brain morphogenesis. Notably, 10 of these genes encode proteins potentially limiting the progression of Alzheimer's disease. These data provide support for a role of 1,25-dihydroxyvitamin D3 in brain disease prevention. The possible consequences of circannual or chronic vitamin D insufficiencies on a tissue with a low regenerative potential such as the brain should be considered.
Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Calcitriol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/fisiopatologia , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , RNA Mensageiro/genética , Transcriptoma/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Linhagem Celular , Progressão da Doença , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/fisiologia , Regulação da Expressão Gênica/genética , Humanos , Transtornos Mentais/genética , Transtornos Mentais/fisiopatologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Doença de Parkinson/genética , Doença de Parkinson/fisiopatologia , Receptores de Calcitriol/efeitos dos fármacos , Receptores de Calcitriol/genética , Elemento de Resposta à Vitamina D/efeitos dos fármacos , Elemento de Resposta à Vitamina D/genéticaRESUMO
Synchrotron Microbeam Radiation Therapy (MRT) relies on the spatial fractionation of the synchrotron photon beam into parallel micro-beams applying several hundred of grays in their paths. Several works have reported the therapeutic interest of the radiotherapy modality at preclinical level, but biological mechanisms responsible for the described efficacy are not fully understood to date. The aim of this study was to identify the early transcriptomic responses of normal brain and glioma tissue in rats after MRT irradiation (400Gy). The transcriptomic analysis of similarly irradiated normal brain and tumor tissues was performed 6 hours after irradiation of 9 L orthotopically tumor-bearing rats. Pangenomic analysis revealed 1012 overexpressed and 497 repressed genes in the irradiated contralateral normal tissue and 344 induced and 210 repressed genes in tumor tissue. These genes were grouped in a total of 135 canonical pathways. More than half were common to both tissues with a predominance for immunity or inflammation (64 and 67% of genes for normal and tumor tissues, respectively). Several pathways involving HMGB1, toll-like receptors, C-type lectins and CD36 may serve as a link between biochemical changes triggered by irradiation and inflammation and immunological challenge. Most immune cell populations were involved: macrophages, dendritic cells, natural killer, T and B lymphocytes. Among them, our results highlighted the involvement of Th17 cell population, recently described in tumor. The immune response was regulated by a large network of mediators comprising growth factors, cytokines, lymphokines. In conclusion, early response to MRT is mainly based on inflammation and immunity which appear therefore as major contributors to MRT efficacy.
Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Genes MHC da Classe II/efeitos da radiação , Glioma/genética , Glioma/radioterapia , Imunidade Adaptativa/genética , Imunidade Adaptativa/efeitos da radiação , Animais , Encéfalo/imunologia , Encéfalo/efeitos da radiação , Neoplasias Encefálicas/imunologia , Linhagem Celular Tumoral , Expressão Gênica/efeitos da radiação , Perfilação da Expressão Gênica , Glioma/imunologia , Imunidade Inata/genética , Imunidade Inata/efeitos da radiação , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Radioterapia/métodos , Ratos , Ratos Endogâmicos F344 , Transdução de Sinais/imunologia , Transdução de Sinais/efeitos da radiação , SíncrotronsRESUMO
Tumor invasion or infiltration of adjacent tissues is the source of clinical challenges in diagnosis as well as prevention and treatment. Among brain tumors, infiltration of the adjacent tissues with diverse pleiotropic mechanisms is frequently encountered in benign meningiomas. We assessed whether a multiparametric analysis of meningiomas based on data from both clinical observations and molecular analyses could provide a consistent and accurate appraisal of invasive and infiltrative phenotypes and help determine the diagnosis of these tumors. Tissue analyses of 37 meningiomas combined enzyme-linked immunosorbent assay (ELISA) and surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF) assays of two different protein biomarkers (thrombospondin 1 and a phosphorylated form of vimentin) as well as gene expression analyses with oligonucleotide micro-arrays. Up to four different clinical and molecular parameters were then examined for tumor classification. From this study, we were able to cluster 36 out of the 37 tumors into two different subsets corresponding to infiltrative/invasive and non-infiltrative tumors. In addition, meningiomas that invade brain and those that infiltrate the neighboring skull bone exhibited no distinguishable molecular features. Our multi-parameter analysis that combines clinical data, transcriptomic and molecular assays clearly reveals the heterogeneity of meningiomas and distinguishes the intrinsically infiltrative/invasive tumors from the non-infiltrative meningiomas.
Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Meníngeas/química , Neoplasias Meníngeas/metabolismo , Meningioma/química , Meningioma/metabolismo , Pessoa de Meia-Idade , Fenótipo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trombospondina 1/análiseRESUMO
Gliomas such as oligodendrogliomas (ODG) and glioblastomas (GBM) are brain tumours with different clinical outcomes. Histology-based classification of these tumour types is often difficult. Therefore the first aim of this study was to gain microRNA data that can be used as reliable signatures of oligodendrogliomas and glioblastomas. We investigated the levels of 282 microRNAs using membrane-array hybridisation and real-time PCR in ODG, GBM and control brain tissues. In comparison to these control tissues, 26 deregulated microRNAs were identified in tumours and the tissue levels of seven microRNAs (miR-21, miR-128, miR-132, miR-134, miR-155, miR-210 and miR-409-5p) appropriately discriminated oligodendrogliomas from glioblastomas. Genomic, epigenomic and host gene expression studies were conducted to investigate the mechanisms involved in these deregulations. Another aim of this study was to better understand glioma physiopathology looking for targets of deregulated microRNAs. We discovered that some targets of these microRNAs such as STAT3, PTBP1 or SIRT1 are differentially expressed in gliomas consistent with deregulation of microRNA expression. Moreover, MDH1, the target of several deregulated microRNAs, is repressed in glioblastomas, making an intramitochondrial-NAD reduction mediated by the mitochondrial aspartate-malate shuttle unlikely. Understanding the connections between microRNAs and bioenergetic pathways in gliomas may lead to identification of novel therapeutic targets.
Assuntos
Glioma/genética , Glioma/metabolismo , MicroRNAs/genética , Western Blotting , Hipóxia Celular/genética , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Ilhas de CpG/genética , Metilação de DNA/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Técnicas In Vitro , Reação em Cadeia da Polimerase , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
OBJECTIVE: Investigating whether extracellular factors are possible actors in tumoral progression in bladder carcinoma. METHODS: RT112/G2 bladder tumour cells were grown in presence of TGFbeta and analysed by immunological and cDNA microarray techniques. RESULTS: TGFbeta inhibited cell proliferation, reduced TNFalpha- and IFNgamma-induced apoptosis by decreasing TNFalpha-RI and IFNgamma-R antigen expression. It also inhibited cleaved caspase 8 and 9 expression, decreased E-cadherin, and increased BclxL and cyclooxygenase-2 expression. The cDNA microarray approach showed that TGFbeta up-regulated the expression of genes with defined roles in tumoral progression sometimes associated with poor outcome in bladder cancer. CONCLUSION: These results suggest that a part of the bladder tumoral progression process may be related to the action of exogenous TGFbeta confirming the possible role for the microenvironment.