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The aim of this study was to identify metabolomic signatures associated with the gliomagenesis pathway (IDH-mutant or IDH-wt) and tumor grade of diffuse gliomas (DGs) according to the 2021 WHO classification on frozen samples and to evaluate the diagnostic performances of these signatures in tumor samples that are formalin-fixed and paraffin-embedded (FFPE). An untargeted metabolomic study was performed using liquid chromatography/mass spectrometry on a cohort of 213 DG samples. Logistic regression with LASSO penalization was used on the frozen samples to build classification models in order to identify IDH-mutant vs. IDH-wildtype DG and high-grade vs low-grade DG samples. 2-Hydroxyglutarate (2HG) was a metabolite of interest to predict IDH mutational status and aminoadipic acid (AAA) and guanidinoacetic acid (GAA) were significantly associated with grade. The diagnostic performances of the models were 82.6% AUC, 70.6% sensitivity and 80.4% specificity for 2HG to predict IDH status and 84.7% AUC, 78.1% sensitivity and 73.4% specificity for AAA and GAA to predict grade from FFPE samples. Thus, this study showed that AAA and GAA are two novel metabolites of interest in DG and that metabolomic data can be useful in the classification of DG, both in frozen and FFPE samples.
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Neoplasias Encefálicas , Glioma , Humanos , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/química , Formaldehído , Parafina , Adhesión en Parafina/métodos , Isocitrato Deshidrogenasa/genética , Glioma/diagnóstico , Glioma/genética , MutaciónRESUMEN
Glioblastomas (GBs) are incurable brain tumors. The persistence of aggressive stem-like tumor cells after cytotoxic treatments compromises therapeutic efficacy, leading to GBM recurrence. Forcing the GBM cells to irreversibly abandon their aggressive stem-like phenotype may offer an alternative to conventional cytotoxic treatments. Here, we show that the RNA binding protein CELF2 is strongly expressed in mitotic and OLIG2-positive GBM cells, while it is downregulated in differentiated and non-mitotic cells by miR-199a-3p, exemplifying GBM intra-tumor heterogeneity. Using patient-derived cells and human GBM samples, we demonstrate that CELF2 plays a key role in maintaining the proliferative/OLIG2 cell phenotype with clonal and tumorigenic properties. Indeed, we show that CELF2 deficiency in patient-derived GSCs drastically reduced tumor growth in the brains of nude mice. We further show that CELF2 promotes TRIM28 and G9a expression, which drive a H3K9me3 epigenetic profile responsible for the silencing of the SOX3 gene. Thus, CELF2, which is positively correlated with OLIG2 and Ki67 expression in human GBM samples, is inversely correlated with SOX3 and miR-199a-3p. Accordingly, the invalidation of SOX3 in CELF2-deficient patient-derived cells rescued proliferation and OLIG2 expression. Finally, patients expressing SOX3 above the median level of expression tend to have a longer life expectancy. CELF2 is therefore a crucial target for the malignant potential of GBM and warrants attention when developing novel anticancer strategies.
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Schweinfurthins (SWs) are naturally occurring prenylated stilbenes with promising anticancer properties. They act through a novel mechanism of action similar to that of other families of natural compounds. Their known target, oxysterol-binding protein (OSBP), plays a crucial role in controlling the intracellular distribution of cholesterol. We synthesized 15 analogues of SWs and demonstrated for the first time that their cytotoxicity as well as that of natural derivatives correlates with their affinity for OSBP. Through this extensive SAR study, we selected one synthetic analogue obtained in one step from SW-G. Using its fluorescence properties, we showed that this compound recapitulates the effect of natural SW-G in cells and confirmed that it leads to cell death via the same mechanism. Finally, after pilot PK experiments, we provided the first evidence of its in vivo efficacy in combination with temozolomide in a patient-derived glioblastoma xenograft model.
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Oxiesteroles , Receptores de Esteroides , Humanos , Receptores de Esteroides/metabolismo , Colesterol/metabolismoRESUMEN
Glioblastomas (GBM) are heterogeneous tumors with high metabolic plasticity. Their poor prognosis is linked to the presence of glioblastoma stem cells (GSC), which support resistance to therapy, notably to temozolomide (TMZ). Mesenchymal stem cells (MSC) recruitment to GBM contributes to GSC chemoresistance, by mechanisms still poorly understood. Here, we provide evidence that MSCs transfer mitochondria to GSCs through tunneling nanotubes, which enhances GSCs resistance to TMZ. More precisely, our metabolomics analyses reveal that MSC mitochondria induce GSCs metabolic reprograming, with a nutrient shift from glucose to glutamine, a rewiring of the tricarboxylic acid cycle from glutaminolysis to reductive carboxylation and increase in orotate turnover as well as in pyrimidine and purine synthesis. Metabolomics analysis of GBM patient tissues at relapse after TMZ treatment documents increased concentrations of AMP, CMP, GMP, and UMP nucleotides and thus corroborate our in vitro analyses. Finally, we provide a mechanism whereby mitochondrial transfer from MSCs to GSCs contributes to GBM resistance to TMZ therapy, by demonstrating that inhibition of orotate production by Brequinar (BRQ) restores TMZ sensitivity in GSCs with acquired mitochondria. Altogether, these results identify a mechanism for GBM resistance to TMZ and reveal a metabolic dependency of chemoresistant GBM following the acquisition of exogenous mitochondria, which opens therapeutic perspectives based on synthetic lethality between TMZ and BRQ. Significance: Mitochondria acquired from MSCs enhance the chemoresistance of GBMs. The discovery that they also generate metabolic vulnerability in GSCs paves the way for novel therapeutic approaches.
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Neoplasias Encefálicas , Glioblastoma , Células Madre Mesenquimatosas , Humanos , Glioblastoma/tratamiento farmacológico , Resistencia a Antineoplásicos , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Temozolomida/farmacología , Mitocondrias , Células Madre NeoplásicasRESUMEN
Glioblastoma (GBM) is the most deadly type of malignant brain tumor, despite extensive molecular analyses of GBM cells. In recent years, the tumor microenvironment (TME) has been recognized as an important player and therapeutic target in GBM. However, there is a need for a full and integrated understanding of the different cellular and molecular components involved in the GBM TME and their interactions for the development of more efficient therapies. In this review, we provide a comprehensive report of the GBM TME, which assembles the contributions of physicians and translational researchers working on brain tumor pathology and therapy in France. We propose a holistic view of the subject by delineating the specific features of the GBM TME at the cellular, molecular, and therapeutic levels.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/terapia , Glioblastoma/tratamiento farmacológico , Microambiente Tumoral/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologíaRESUMEN
Cell motility is critical for tumor malignancy. Metabolism being an obligatory step in shaping cell behavior, we looked for metabolic weaknesses shared by motile cells across the diverse genetic contexts of patients' glioblastoma. Computational analyses of single-cell transcriptomes from thirty patients' tumors isolated cells with high motile potential and highlighted their metabolic specificities. These cells were characterized by enhanced mitochondrial load and oxidative stress coupled with mobilization of the cysteine metabolism enzyme 3-Mercaptopyruvate sulfurtransferase (MPST). Functional assays with patients' tumor-derived cells and -tissue organoids, and genetic and pharmacological manipulations confirmed that the cells depend on enhanced ROS production and MPST activity for their motility. MPST action involved protection of protein cysteine residues from damaging hyperoxidation. Its knockdown translated in reduced tumor burden, and a robust increase in mice survival. Starting from cell-by-cell analyses of the patients' tumors, our work unravels metabolic dependencies of cell malignancy maintained across heterogeneous genomic landscapes.
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Glioblastoma , Ratones , Animales , Glioblastoma/genética , Cisteína/metabolismo , Sulfurtransferasas/genética , Sulfurtransferasas/metabolismo , Estrés Oxidativo , Movimiento Celular/genéticaRESUMEN
Recent evidence suggests that the chimeric protein SETMAR is a factor of interest in cancer, especially in glioblastoma. However, little is known about the expression of this protein in glioblastoma tissues, and no study has been done to assess if SETMAR could be a prognostic and/or diagnostic marker of glioblastoma. We analyzed protein extracts of 47 glioblastoma samples coming from a local and a national cohort of patients. From the local cohort, we obtained localized biopsies from the central necrosis area, the tumor, and the perilesional brain. From the French Glioblastoma Biobank (FGB), we obtained three types of samples: from the same tumors before and after treatment, from long survivors, and from very short survivors. We studied the correlations between SETMAR amounts, clinical profiles of patients and other associated proteins (PTN, snRNP70 and OLIG2). In glioblastoma tissues, the shorter isoform of SETMAR (S-SETMAR) was predominant over the full-length isoform (FL-SETMAR), and the expression of both SETMAR variants was higher in the tumor compared to the perilesional tissues. Data from the FGB showed that SETMAR amounts were not different between the initial tumors and tumor relapses after treatment. These data also showed a trend toward higher amounts of S-SETMAR in long survivors. In localized biopsies, we found a positive correlation between good prognosis and large amounts of S-SETMAR in the perilesional area. This is the main result presented here: survival in Glioblastoma is correlated with amounts of S-SETMAR in perilesional brain, which should be considered as a new relevant prognosis marker.
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There is great interest in understanding how the cancer stem cell population may be maintained in solid tumors. Here, we show that tumor cells exhibiting stem-like properties and expression of pluripotency markers NANOG and OCT4 can arise from original differentiated tumor cells freshly isolated from human glioblastomas (GBM) and that have never known any serum culture conditions. Induction of EGR1 by EGFR/ERK signaling promoted cell conversion from a less aggressive, more differentiated cellular state to a self-renewing and strongly tumorigenic state, expressing NANOG and OCT4. Expression of these pluripotency markers occurred before the cells re-entered the cell cycle, demonstrating their capacity to change and dedifferentiate without any cell divisions. In differentiated GBM cells, ERK-mediated repression of miR-199a-3p induced EGR1 protein expression and triggered dedifferentiation. Overall, this signaling pathway constitutes an ERK-mediated "toggle switch" that promotes pluripotency marker expression and stem-like features in GBM cells. SIGNIFICANCE: This study defines an ERK-mediated molecular mechanism of dedifferentiation of GBM cells into a stem-like state, expressing markers of pluripotency.See related commentary by Koncar and Agnihotri, p. 3195.
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Glioblastoma , MicroARNs , Desdiferenciación Celular , Diferenciación Celular , Proteína 1 de la Respuesta de Crecimiento Precoz , Glioblastoma/genética , Humanos , MicroARNs/genética , Proteína Homeótica Nanog/genética , Células Madre NeoplásicasRESUMEN
Glioblastoma (GBM) is the brain tumor with the worst prognosis composed of a cell subpopulation called Glioblastoma Stem-like Cells (GSCs) responsible for tumor recurrence mediated by cell invasion. GSCs persist in a hypoxic microenvironment which promotes extracellular adenosine production and activation of the A3 Adenosine Receptor (A3AR), therefore, the aim of this study was to determine the role of extracellular adenosine and A3AR on GSCs invasion under hypoxia. GSCs were obtained from a U87MG cell line and primary cultures of GBM patients, and then incubated under normoxia or hypoxia. Gene expression was evaluated by RNAseq, RT-qPCR, and western blot. Cell migration was measured by spreading and transwell boyden chamber assays; cell invasion was evaluated by Matrigel-coated transwell, ex vivo brain slice, and in vivo xenograft assays. The contribution of A3AR on cell migration/invasion was evaluated using the A3AR antagonist, MRS1220. Extracellular adenosine production was higher under hypoxia than normoxia, mainly by the catalytic action of the prostatic acid phosphatase (PAP), promoting cell migration/invasion in a HIF-2-dependent process. A3AR blockade decreased cell migration/invasion and the expression of Epithelial-Mesenchymal Transition markers. In conclusion, high levels of extracellular adenosine production enhance cell migration/invasion of GSCs, through HIF-2/PAP-dependent activation of A3AR under hypoxia.
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Adenosina/metabolismo , Neoplasias Encefálicas/metabolismo , Movimiento Celular , Glioblastoma/metabolismo , Células Madre Neoplásicas/metabolismo , Receptor de Adenosina A3/metabolismo , Fosfatasa Ácida/genética , Fosfatasa Ácida/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioblastoma/genética , Glioblastoma/patología , Humanos , Ratones Endogámicos NOD , Ratones SCID , Invasividad Neoplásica , Células Madre Neoplásicas/patología , Receptor de Adenosina A3/genética , Transducción de Señal , Células Tumorales Cultivadas , Hipoxia Tumoral , Microambiente TumoralRESUMEN
Although a growing body of evidence indicates that phenotypic plasticity exhibited by glioblastoma cells plays a central role in tumor development and post-therapy recurrence, the master drivers of their aggressiveness remain elusive. Here we mapped the changes in active (H3K4me3) and repressive (H3K27me3) histone modifications accompanying the repression of glioblastoma stem-like cells tumorigenicity. Genes with changing histone marks delineated a network of transcription factors related to cancerous behavior, stem state, and neural development, highlighting a previously unsuspected association between repression of ARNT2 and loss of cell tumorigenicity. Immunohistochemistry confirmed ARNT2 expression in cell sub-populations within proliferative zones of patients' glioblastoma. Decreased ARNT2 expression was consistently observed in non-tumorigenic glioblastoma cells, compared to tumorigenic cells. Moreover, ARNT2 expression correlated with a tumorigenic molecular signature at both the tissue level within the tumor core and at the single cell level in the patients' tumors. We found that ARNT2 knockdown decreased the expression of SOX9, POU3F2 and OLIG2, transcription factors implicated in glioblastoma cell tumorigenicity, and repressed glioblastoma stem-like cell tumorigenic properties in vivo. Our results reveal ARNT2 as a pivotal component of the glioblastoma cell tumorigenic signature, located at a node of a transcription factor network controlling glioblastoma cell aggressiveness.
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Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Neoplasias Encefálicas/metabolismo , Cromatina/metabolismo , Glioblastoma/metabolismo , Anciano , Animales , Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Células Cultivadas , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Glioblastoma/genética , Glioblastoma/patología , Código de Histonas , Proteínas de Homeodominio/metabolismo , Humanos , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Invasividad Neoplásica/fisiopatología , Trasplante de Neoplasias , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Factor de Transcripción 2 de los Oligodendrocitos/metabolismo , Factores del Dominio POU/metabolismo , Factor de Transcripción SOX9/metabolismoAsunto(s)
Neoplasias Encefálicas , Glioblastoma , Células Madre Neoplásicas , Animales , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Fenómenos Fisiológicos Celulares/fisiología , Resistencia a Antineoplásicos , Glioblastoma/patología , Glioblastoma/terapia , Humanos , Inmunoterapia , Ratones , Células Madre Neoplásicas/química , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/fisiología , Nicho de Células MadreRESUMEN
[18F]-FDOPA is a labeled amino acid (AA) analog used for positron emission tomography (PET) which is gaining increasing interest in the evaluation of brain tumors (BT). The AA-transporter LAT1 has been shown to be involved in [18F]-FDOPA uptake. The aim of this study was to determine whether the [18F]-FDOPA uptake was correlated with level of LAT1 expression in BT. Twenty-eight BT (including 19 gliomas and 9 metastases) were investigated by [18F]-FDOPA-PET prior to surgery and by anti-LAT1 immunohistochemistry on surgical specimens. The quantitative [18F]-FDOPA measured parameters were SUVmax, SUVmean and SUVpeak. LAT1 expression was quantified using a score (0 to 400). A significant [18F]-FDOPA uptake was associated with a LAT1 score ≥ 100 (p = 0.02) but there was no linear correlation between intensity of [18F]-FDOPA uptake and score of LAT1 expression whatever the parameters considered. LAT1 expression alone is not sufficient to explain variation of intensity of [18F]-FDOPA uptake in BT.
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Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Neoplasias Encefálicas/metabolismo , Dihidroxifenilalanina/farmacocinética , Radioisótopos de Flúor/farmacocinética , Tomografía de Emisión de Positrones , Radiofármacos/farmacocinética , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Femenino , Glioma/diagnóstico por imagen , Glioma/metabolismo , Glioma/patología , Glioma/cirugía , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana EdadRESUMEN
Glioblastomas are incurable primary brain tumors that affect patients of all ages. The aggressiveness of this cancer has been attributed in part to the persistence of treatment-resistant glioblastoma stem-like cells. We have previously discovered the tumor-suppressor properties of the microRNA cluster miR-302-367, representing a potential treatment for glioblastoma. Here, we attempted to develop a cell-based therapy by taking advantage of the capability of glioma cells to secrete exosomes that enclose small RNA molecules. We engineered primary glioma cells to stably express the miR-302-367. Remarkably, these cells altered, in a paracrine-dependent manner, the expression of stemness markers, the proliferation and the tumorigenicity of neighboring glioblastoma cells. Further characterization of the secretome derived from miR-302-367 expressing cells showed that a large amount of miR-302-367 was enclosed in exosomes, which were internalized by the neighboring glioblastoma cells. This miR-302-367 cell-to-cell transfer resulted in the inhibition of its targets such as CXCR4/SDF1, SHH, cyclin D, cyclin A and E2F1. Orthotopic xenograft of miR-302-367-expressing cells together with glioblastoma stem-like cells efficiently altered the tumor development in mice brain.
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Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , MicroARNs/biosíntesis , Familia de Multigenes , Proteínas de Neoplasias/biosíntesis , ARN Neoplásico/biosíntesis , Animales , Tratamiento Basado en Trasplante de Células y Tejidos , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Ratones , MicroARNs/genética , Proteínas de Neoplasias/genética , ARN Neoplásico/genéticaRESUMEN
Cell populations with differing proliferative, stem-like and tumorigenic states co-exist in most tumors and especially malignant gliomas. Whether metabolic variations can drive this heterogeneity by controlling dynamic changes in cell states is unknown. Metabolite profiling of human adult glioblastoma stem-like cells upon loss of their tumorigenicity revealed a switch in the catabolism of the GABA neurotransmitter toward enhanced production and secretion of its by-product GHB (4-hydroxybutyrate). This switch was driven by succinic semialdehyde dehydrogenase (SSADH) downregulation. Enhancing GHB levels via SSADH downregulation or GHB supplementation triggered cell conversion into a less aggressive phenotypic state. GHB affected adult glioblastoma cells with varying molecular profiles, along with cells from pediatric pontine gliomas. In all cell types, GHB acted by inhibiting α-ketoglutarate-dependent Ten-eleven Translocations (TET) activity, resulting in decreased levels of the 5-hydroxymethylcytosine epigenetic mark. In patients, low SSADH expression was correlated with high GHB/α-ketoglutarate ratios, and distinguished weakly proliferative/differentiated glioblastoma territories from proliferative/non-differentiated territories. Our findings support an active participation of metabolic variations in the genesis of tumor heterogeneity.
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Neoplasias Encefálicas/metabolismo , Carcinogénesis/metabolismo , Glioma/metabolismo , Hidroxibutiratos/metabolismo , Células Madre Neoplásicas/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Anciano , Animales , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Carcinogénesis/patología , Muerte Celular/fisiología , Proliferación Celular/fisiología , Niño , Preescolar , Femenino , Glioma/patología , Glioma/cirugía , Humanos , Masculino , Ratones Desnudos , Persona de Mediana Edad , Trasplante de Neoplasias , Células Madre Neoplásicas/patología , Succionato-Semialdehído Deshidrogenasa/metabolismoRESUMEN
Positron emission tomography using radiolabeled amino acid (PET-AA) appears to be promising in distinguishing between recurrent tumour and radionecrosis in the follow-up of brain metastasis (BM). The amino acid transporter LAT1 and its cofactor CD98, which are involved in AA uptake, have never been investigated in BM. The aim of our study was to determine and compare the expression of LAT1 and CD98 in BM and in non-tumoral brain tissue (NT). The expression of LAT1 and CD98 were studied by immunohistochemistry in 67 BM, including 18 BM recurrences after radiotherapy, in 53 NT, and in 13 cases of patients with previously irradiated brain tumor and investigated by [18F] FDOPA-PET. LAT1 and CD98 expression were detected in 98.5% and 59.7% of BM respectively and were significantly associated with BM tissue as compared to NT (p<0.001). LAT1 expression in recurrent BM was significantly increased as compared to newly occurring BM. Ten cases investigated by [18F] FDOPA-PET corresponding to recurrent BM displayed significant [18F] FDOPA uptake and LAT1 overexpression whereas three cases corresponding to radionecrosis showed no or low uptake and LAT1 expression. LAT1 expression level and [18F] FDOPA uptake were significantly correlated. In conclusion, we hypothesized that BM may overexpress the AA transporter LAT1. We have shown that LAT1 overexpression was common in BM and was specific for BM as compared to healthy brain. These results could explain the specific BM uptake on PET-AA.
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Neoplasias Encefálicas , Dihidroxifenilalanina/administración & dosificación , Regulación Neoplásica de la Expresión Génica , Transportador de Aminoácidos Neutros Grandes 1/biosíntesis , Proteínas de Neoplasias/biosíntesis , Tomografía de Emisión de Positrones/métodos , Radiofármacos/administración & dosificación , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Femenino , Humanos , Masculino , Metástasis de la Neoplasia , Trazadores RadiactivosRESUMEN
Glioblastomas are the most common primary brain tumors, highly vascularized, infiltrating, and resistant to current therapies. This cancer leads to a fatal outcome in less than 18 months. The aggressive behavior of glioblastomas, including resistance to current treatments and tumor recurrence, has been attributed to glioma stemlike/progenitor cells. The transcription factor EGR1 (early growth response 1), a member of a zinc finger transcription factor family, has been described as tumor suppressor in gliomas when ectopically overexpressed. Although EGR1 expression in human glioblastomas has been associated with patient survival, its precise location in tumor territories as well as its contribution to glioblastoma progression remain elusive. In the present study, we show that EGR1-expressing cells are more frequent in high grade gliomas where the nuclear expression of EGR1 is restricted to proliferating/progenitor cells. We show in primary cultures of glioma stemlike cells that EGR1 contributes to stemness marker expression and proliferation by orchestrating a PDGFA-dependent growth-stimulatory loop. In addition, we demonstrate that EGR1 acts as a positive regulator of several important genes, including SHH, GLI1, GLI2, and PDGFA, previously linked to the maintenance and proliferation of glioma stemlike cells.
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Comunicación Autocrina , Neoplasias Encefálicas/metabolismo , Proliferación Celular , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/biosíntesis , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/patología , Humanos , Masculino , Células Madre Neoplásicas/patología , Células Tumorales CultivadasRESUMEN
Glioblastoma is an aggressive brain tumor characterized by its high propensity for local invasion, formation of secondary foci within the brain, as well as areas of necrosis. This study aims to (i) provide a technical approach to reproduce features of the disease in vitro and (ii) characterize the tumor/host brain tissue interaction at the molecular level. Human engineered neural tissue (ENT) obtained from pluripotent stem cells was generated and co-cultured with human glioblastoma-initiating cells. Within two weeks, glioblastoma cells invaded the nervous tissue. This invasion displayed features of the disease in vivo: a primary tumor mass, diffuse migration of invading single cells into the nervous tissue, secondary foci, as well as peritumoral cell death. Through comparative molecular analyses, this model allowed the identification of more than 100 genes that are specifically induced and up-regulated by the nervous tissue/tumor interaction. Notably the type I interferon response, extracellular matrix-related genes were most highly represented and showed a significant correlation with patient survival. In conclusion, glioblastoma development within a nervous tissue can be engineered in vitro, providing a relevant model to study the disease and allows the identification of clinically-relevant genes induced by the tumor/host tissue interaction.
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Neoplasias Encefálicas/patología , Glioblastoma/patología , Animales , Línea Celular , Células Cultivadas , Femenino , Humanos , Inmunohistoquímica , Ratones , Reacción en Cadena de la Polimerasa , Embarazo , Células Madre/citología , Ingeniería de TejidosRESUMEN
BACKGROUND: The differential diagnosis between infiltrative glioma (IG) and benign or curable glial lesions, such as gliosis, pilocytic astrocytoma, dysembryoplastic neuroepithelial tumor, ganglioglioma, or demyelinating disease, may be challenging for the pathologist because specific markers are lacking. Recently, we described a strong EGFR immunolabelling pattern in cells with a high nuclear to cytoplasmic ratio that enables the discrimination of low-grade IG from gliosis. The aim of this study was to extend our observation to high-grade glioma to assess whether EGFR expression pattern is of value in the discrimination of all IG from noninfiltrative glial lesions (NIG), including gliosis, benign tumors, and demyelinating disease. METHODS: One hundred one IG and 58 NIG were compared for immunohistochemical expression of EGFR with use of an antibody that recognizes an epitope in the extracellular domain of both EGFRwt and EGFRvIII. Highly EGFR-positive cells with a high nuclear to cytoplasmic ratio were isolated and further characterized. RESULTS: Cells with intense EGFR staining and a high nuclear to cytoplasmic ratio were significantly associated with the diagnosis of IG (P < .0001). The sensitivity and specificity of this staining pattern for the diagnosis of IG were 95% and 100%, respectively. EGFR expression was independent of IDH1 mutations and EGFR amplification. Finally, we showed that these particular cells displayed the phenotype and properties of glial progenitors and coexpressed CXCR4, a marker of invasiveness. CONCLUSIONS: We demonstrate that cells with intense EGFR staining and a high nuclear to cytoplasmic ratio are specific criteria for the diagnosis of IG, irrespective of grade, histological subtype, and progression pathway, and their identification represents a tool to discriminate IG from benign or curable glial lesions.
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Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/patología , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Receptores ErbB/metabolismo , Glioma/patología , Adulto , Biomarcadores de Tumor/genética , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Niño , Receptores ErbB/genética , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Glioma/genética , Glioma/metabolismo , Humanos , Técnicas para Inmunoenzimas , Hibridación Fluorescente in Situ , Masculino , Estudios Retrospectivos , Células Tumorales CultivadasRESUMEN
Stem cell-like properties of glioma initiating cells (GiCs) fuel glioblastoma (GBM) development by providing the different cell types that comprise the tumor. It is therefore likely that the molecular circuitries that regulate their decision to self-renew or commit to a more differentiated state may offer targets for future innovative therapies. In previous micro-RNA profiling studies to search for regulators of stem cell plasticity, we identified miR-18a* as a potential candidate and its expression correlated with the stemness state. Here, using human GiCs we found that miR-18a* expression promotes clonal proliferation in vitro and tumorigenicity in vivo. Mechanistically, ERK-dependent induction of miR-18a* directly represses expression of DLL3, an autocrine inhibitor of NOTCH, thus enhancing the level of activated NOTCH-1. Activated NOTCH-1 in turn is required for sustained ERK activation. This feed-forward loop, driven by miR-18a*, is required to turn on the SHH-GLI-NANOG network, essential for GiC self-renewal. Hence, by tightly regulating expression of DLL3, miR-18a* constitutes an important signaling mediator for fine tuning the level of GiC self-renewal.