a-novel-high-resolution-vivo-imaging-technique-to-study-dynamic

A Novel High-resolution <em>In vivo</em> Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a ...

Hospital for Sick Children, Toronto Medical Discovery Tower

Glial fibrillary acidic protein (GFAP) is an intermediate filament expressed in glial cells that stabilizes and maintains the cytoskeleton of normal astrocytes. In glial tumors, GFAP expression is frequently lost with increasing grade of malignancy, suggesting that GFAP is important for maintaining glial cell morphology or regulating astrocytoma cell growth. Most permanent human glioma cell lines are GFAP negative by immunocytochemistry. Given that the GFAP gene is not mutated in human glioma specimens or glioma cell lines, we considered epigenetic mechanisms, such as promoter methylation, as a cause of silencing of GFAP in these tumors. In this study, we treated known GFAP-negative glioma cell lines with 5-aza-2'-deoxycytidine to examine GFAP promoter hypermethylation. Additionally, we performed bisulfite sequencing on primary glioma samples and glioma cell lines and showed an inverse relationship between GFAP promoter methylation status and GFAP expression. Using a gene reporter assay with the GFAP promoter cloned upstream of a luciferase gene, we showed that methylation of the GFAP promoter downregulates the expression of the luciferase gene. Our results suggest that epigenetic silencing of the GFAP gene through DNA methylation of its promoter region may be one mechanism by which GFAP is downregulated in human gliomas and glioma cell lines.

Epigenetic regulation of glial fibrillary acidic protein by DNA methylation in human malignant gliomas.

Glial fibrillary acidic protein (GFAP) est un filament interm&eacute;diaire exprim&eacute; dans les cellules gliales qui stabilise et maintient le cytosquelette des astrocytes normaux. Dans les tumeurs gliales, expression GFAP est souvent perdue avec l&#39;augmentation de grade de malignit&eacute;, sugg&eacute;rant que la GFAP est important pour maintenir la morphologie des cellules gliales ou de r&eacute;gulation de la croissance cellulaire astrocytome. Des lign&eacute;es de cellules de gliome humain plus permanentes sont GFAP n&eacute;gatif par immunocytochimie. &Eacute;tant donn&eacute; que le g&egrave;ne GFAP n&#39;est pas mut&eacute; dans les sp&eacute;cimens de gliome humain ou lign&eacute;es de cellules de gliome, nous avons consid&eacute;r&eacute; des m&eacute;canismes &eacute;pig&eacute;n&eacute;tiques, tels que de la m&eacute;thylation du promoteur, comme une cause de mise sous silence de l&#39;accord-cadre dans ces tumeurs. Dans cette &eacute;tude, nous avons trait&eacute; connues lign&eacute;es de cellules de gliome GFAP n&eacute;gatif avec la 5-aza-2&#39;-deoxycytidine d&#39;examiner l&#39;hyperm&eacute;thylation du promoteur GFAP. En outre, nous avons effectu&eacute; le s&eacute;quen&ccedil;age du bisulfite sur &eacute;chantillons de gliomes primaires et des lign&eacute;es de cellules de gliome et a montr&eacute; une relation inverse entre le statut de m&eacute;thylation promoteur GFAP et expression GFAP. En utilisant un test de journaliste g&eacute;nique avec le promoteur GFAP clon&eacute; en amont d&#39;un g&egrave;ne de la lucif&eacute;rase, nous avons montr&eacute; que la m&eacute;thylation de la GFAP promoteur entra&icirc;ne l&#39;expression du g&egrave;ne de la lucif&eacute;rase. Nos r&eacute;sultats sugg&egrave;rent que l&#39;&eacute;pig&eacute;n&eacute;tique silencing du g&egrave;ne GFAP par m&eacute;thylation de l&#39;ADN de sa r&eacute;gion promotrice peut &ecirc;tre un m&eacute;canisme par lequel GFAP est diminu&eacute;e dans les gliomes humains et gliome lign&eacute;es cellulaires.

R&eacute;gulation &eacute;pig&eacute;n&eacute;tique de la prot&eacute;ine fibrillaire acide gliale par m&eacute;thylation de l&#39;ADN dans les gliomes malins humaines.

Proteina acida fibrillare gliale (GFAP) &egrave; un filamento intermedio espresso in cellule gliali che stabilizza e mantiene il citoscheletro di astrociti normali. Nei tumori gliali, espressione di GFAP &egrave; frequentemente perso con crescente grado di malignit&agrave;, suggerendo che la GFAP &egrave; importante per mantenere la morfologia delle cellule gliali o regolazione della crescita delle cellule di astrocitoma. Linee di cellule di glioma umano pi&ugrave; permanente sono GFAP negativo di immunocitochimica. Dato che il gene GFAP &egrave; mutato non esemplari di glioma umano o linee cellulari di glioma, siamo considerati meccanismi epigenetici, come metilazione del promotore, a causa del silenzio di GFAP in questi tumori. In questo studio, abbiamo trattato noti linee cellulari di glioma di GFAP-negativo con 5-aza-2&#39;-deoxycytidine esaminare ipermetilazione del promotore GFAP. Inoltre, abbiamo eseguito del bisolfuro su campioni di glioma primario e linee cellulari di glioma e ha mostrato un rapporto inverso tra stato di metilazione di GFAP promotore ed espressione di GFAP. Con un saggio di reporter gene promotore GFAP clonato a monte del gene luciferasi, abbiamo dimostrato che la metilazione della GFAP promotore sottoregola l&#39;espressione del gene della luciferasi. I nostri risultati suggeriscono che tacere epigenetico del gene GFAP attraverso la metilazione del DNA della regione promotore pu&ograve; essere un meccanismo da cui GFAP &egrave; downregolata nei gliomi umani e Glioma delle linee cellulari.

Regolamento epigenetica della proteina acida fibrillare gliale di metilazione del DNA nei gliomi maligni umani.

Proliferating embryonic and cancer cells preferentially use aerobic glycolysis to support growth, a metabolic alteration commonly referred to as the "Warburg effect." Here, we show that the glycolytic enzyme hexokinase 2 (HK2) is crucial for the Warburg effect in human glioblastoma multiforme (GBM), the most common malignant brain tumor. In contrast to normal brain and low-grade gliomas, which express predominantly HK1, GBMs show increased HK2 expression. HK2 expression correlates with worse overall survival of GBM patients. Depletion of HK2, but neither HK1 nor pyruvate kinase M2, in GBM cells restored oxidative glucose metabolism and increased sensitivity to cell death inducers such as radiation and temozolomide. Intracranial xenografts of HK2-depleted GBM cells showed decreased proliferation and angiogenesis, but increased invasion, as well as diminished expression of hypoxia inducible factor 1Î± and vascular endothelial growth factor. In contrast, exogenous HK2 expression in GBM cells led to increased proliferation, therapeutic resistance, and intracranial growth. Growth was dependent on both glucose phosphorylation and mitochondrial translocation mediated by AKT signaling, which is often aberrantly activated in GBMs. Collectively, these findings suggest that therapeutic strategies to modulate the Warburg effect, such as targeting of HK2, may interfere with growth and therapeutic sensitivity of some GBMs.

Hexokinase 2 is a key mediator of aerobic glycolysis and promotes tumor growth in human glioblastoma multiforme.

Prolif&egrave;rent embryonnaires et cellules canc&eacute;reuses pr&eacute;f&eacute;rentiellement utilisent glycolyse a&eacute;robie pour soutenir la croissance, une alt&eacute;ration m&eacute;tabolique commun&eacute;ment appel&eacute; &laquo; l&#39;effet Warburg. &raquo; Ici, nous montrons que l&#39;enzyme glycolytique hexokinase 2 (HK2) est crucial pour l&#39;effet Warburg dans humaines de glioblastome multiforme (GBM), la tumeur maligne au cerveau plus courante. Contrairement &agrave; la normal du cerveau et des gliomes de bas grade, qui expriment principalement HK1, GBM montre une expression accrue HK2. Expression HK2 est corr&eacute;l&eacute;e avec la pire survie globale des patients GBM. Appauvrissement de la couche de HK2, mais ni HK1 ni pyruvate kinase M2, dans GBM cellules restaur&eacute;e m&eacute;tabolisme oxydatif et une sensibilit&eacute; accrue aux inducteurs de mort cellulaire comme la radioth&eacute;rapie et t&eacute;mozolomide. Intracr&acirc;niennes x&eacute;nogreffes de cellules appauvri HK2 GBM a montr&eacute; une diminution de la prolif&eacute;ration et l&#39;angiogen&egrave;se, mais invasion accrue, ainsi qu&#39;expression d&#39;hypoxie inducible factor 1&alpha; et facteur de croissance endoth&eacute;lial vasculaire a diminu&eacute;. En revanche, exog&egrave;ne HK2 expression dans les cellules GBM a conduit &agrave; une prolif&eacute;ration accrue, la r&eacute;sistance th&eacute;rapeutique et croissance intracr&acirc;nienne. Croissance d&eacute;pendait de la phosphorylation du glucose tant de translocation mitochondriale m&eacute;di&eacute;e par la signalisation AKT, qui est souvent anormalement activ&eacute;e dans GBM. collectivement, ces r&eacute;sultats sugg&egrave;rent que les strat&eacute;gies th&eacute;rapeutiques pour moduler l&#39;effet Warburg, telles que le ciblage de HK2, peuvent interf&eacute;rer avec la croissance et sensibilit&eacute; th&eacute;rapeutique de certains GBM.

2 L&#39;hexokinase est un m&eacute;diateur cl&eacute; de la glycolyse a&eacute;robie et favorise la croissance de la tumeur dans le glioblastome humain.

Proliferando embrionali e cellule tumorali preferenzialmente utilizzano la glicolisi aerobica per sostenere la crescita, un&#39;alterazione metabolica, comunemente indicata come il &quot;effetto Warburg&quot;. Qui, ci mostrano che l&#39;enzima glicolitico esochinasi 2 (HK2) sono cruciale per l&#39;effetto Warburg in umano glioblastoma multiforme (GBM), il pi&ugrave; comune tumore cerebrale maligno. Contrariamente al cervello normale e gliomi di basso grado, che si esprimono prevalentemente HK1, GBMs mostrare maggiore espressione HK2. HK2 espressione correla con la peggiore sopravvivenza complessiva dei pazienti GBM. Esaurimento della HK2, ma HK1 n&eacute; piruvato chinasi M2, in GBM cellule metabolismo del glucosio ossidativo restaurato e aumenta la sensibilit&agrave; di induttori di morte cellulare come radiazione e temozolomide. Intracraniche transmigrazione delle cellule GBM HK2-impoverito ha mostrato ridotta proliferazione e l&#39;angiogenesi, ma maggiore invasione, come pure diminuita espressione di ipossia inducible factor 1&alpha; e fattore di crescita vascolare endoteliale. Al contrario, esogeno HK2 espressione in cellule di GBM ha portato alla crescita intracranica aumentata proliferazione e resistenza terapeutica. Crescita dipende dalla fosforilazione di glucosio sia mitocondriale traslocazione mediato da AKT signaling, che spesso in modo anomalo &egrave; attivata in GBMs. collettivamente, questi risultati suggeriscono che le strategie terapeutiche per modulare l&#39;effetto Warburg, come targeting della HK2, possono interferire con crescita e sensibilit&agrave; terapeutica di alcuni GBMs.

2 Esochinasi &egrave; un mediatore chiave della glicolisi aerobica e favorisce la crescita tumorale in umano glioblastoma multiforme.

A key aberrant biological difference between tumor cells and normal differentiated cells is altered metabolism, whereby cancer cells acquire a number of stable genetic and epigenetic alterations to retain proliferation, survive under unfavorable microenvironments and invade into surrounding tissues. A classic biochemical adaptation is the metabolic shift to aerobic glycolysis rather than mitochondrial oxidative phosphorylation, regardless of oxygen availability, a phenomenon termed the "Warburg Effect". Aerobic glycolysis, characterized by high glucose uptake, low oxygen consumption and elevated production of lactate, is associated with a survival advantage as well as the generation of substrates such as fatty acids, amino acids and nucleotides necessary in rapidly proliferating cells. This review discusses the role of key metabolic enzymes and their association with aerobic glycolysis in Glioblastoma Multiforme (GBM), an aggressive, highly glycolytic and deadly brain tumor. Targeting key metabolic enzymes involved in modulating the "Warburg Effect" may provide a novel therapeutic approach either singularly or in combination with existing therapies in GBMs.

Targeting metabolic remodeling in glioblastoma multiforme.

Une diff&eacute;rence biologique aberrante essentielle entre cellules tumorales et des cellules normales diff&eacute;renci&eacute;es est m&eacute;tabolisme modifi&eacute;, par lequel les cellules canc&eacute;reuses acqui&egrave;rent un nombre stable alt&eacute;rations g&eacute;n&eacute;tiques et &eacute;pig&eacute;n&eacute;tiques pour conserver la prolif&eacute;ration, de survivre dans des micro-environnements d&eacute;favorables et d&#39;envahir dans les tissus environnants. Une adaptation biochimique classique est la Maj m&eacute;tabolique de la glycolyse a&eacute;robie plut&ocirc;t que la phosphorylation oxydative mitochondriale, quelle que soit la disponibilit&eacute; de l&#39;oxyg&egrave;ne, un ph&eacute;nom&egrave;ne appel&eacute; &laquo; Effet Warburg &raquo;. La glycolyse a&eacute;robie, caract&eacute;ris&eacute;e par l&#39;hyperglyc&eacute;mie, absorption, consommation d&#39;oxyg&egrave;ne faible et &eacute;lev&eacute;e de production de lactate, est associ&eacute;e &agrave; un avantage de survie ainsi que la g&eacute;n&eacute;ration des substrats tels que les acides gras, acides amin&eacute;s et de nucl&eacute;otides n&eacute;cessaire &agrave; la prolif&eacute;ration rapide de cellules. Cet examen aborde le r&ocirc;le des enzymes m&eacute;taboliques cl&eacute;s et leur association avec la glycolyse a&eacute;robie en glioblastome Multiforme (GBM), une tumeur au cerveau agressif, extr&ecirc;mement glycolytique et mortelle. Ciblage des enzymes m&eacute;taboliques cl&eacute;s impliqu&eacute;s dans la modulation de le &laquo; effet Warburg &raquo; peut fournir une nouvelle approche th&eacute;rapeutique soit individuellement ou en combinaison avec les traitements actuels chez GBM.

Ciblant un remodelage m&eacute;tabolique dans le glioblastome multiforme.

Una chiave aberrante differenza biologica tra cellule tumorali e cellule normali differenziate &egrave; alterato metabolismo, per cui le cellule tumorali acquisiscono un certo numero di alterazioni genetiche ed epigenetiche stabile per mantenere la proliferazione, sopravvivere sotto microambienti sfavorevole e invadere nei tessuti circostanti. Un adattamento biochimico classico &egrave; lo spostamento metabolico aerobica glicolisi, piuttosto che la fosforilazione ossidativa mitocondriale, indipendentemente dalla disponibilit&agrave; di ossigeno, un fenomeno definito &quot;Effetto Warburg&quot;. Glicolisi aerobica, caratterizzata da alto glucosio assorbimento, consumo di ossigeno bassa ed elevata produzione di lattato, &egrave; associato con un vantaggio di sopravvivenza, cos&igrave; come la generazione di substrati quali gli acidi grassi, amminoacidi e nucleotidi necessari nel proliferare rapidamente le cellule. Questa recensione discute il ruolo degli enzimi metabolici chiavi e loro associazione con la glicolisi aerobica in Glioblastoma Multiforme (GBM), un tumore al cervello altamente aggressiva, glicolitica e mortale. Targeting enzimi metabolici chiave coinvolti nel modulare il &quot;effetto Warburg&quot; pu&ograve; fornire un nuovo approccio terapeutico singolarmente o in combinazione con le terapie esistenti nel GBMs.

Targeting rimodellamento metabolica nel glioblastoma multiforme.

Glioblastoma Multiforme (GBM), the most common and lethal primary human brain tumor, exhibits multiple molecular aberrations. We report that loss of the transcription factor GATA4, a negative regulator of normal astrocyte proliferation, is a driver in glioma formation and fulfills the hallmarks of a tumor suppressor gene (TSG). Although GATA4 was expressed in normal brain, loss of GATA4 was observed in 94/163 GBM operative samples and was a negative survival prognostic marker. GATA4 loss occurred through promoter hypermethylation or novel somatic mutations. Loss of GATA4 in normal human astrocytes promoted high-grade astrocytoma formation, in cooperation with other relevant genetic alterations such as activated Ras or loss of TP53. Loss of GATA4 with activated Ras in normal astrocytes promoted a progenitor-like phenotype, formation of neurospheres, and the ability to differentiate into astrocytes, neurons, and oligodendrocytes. Re-expression of GATA4 in human GBM cell lines, primary cultures, and brain tumor-initiating cells suppressed tumor growth in vitro and in vivo through direct activation of the cell cycle inhibitor P21(CIP1), independent of TP53. Re-expression of GATA4 also conferred sensitivity of GBM cells to temozolomide, a DNA alkylating agent currently used in GBM therapy. This sensitivity was independent of MGMT (O-6-methylguanine-DNA-methyltransferase), the DNA repair enzyme which is often implicated in temozolomide resistance. Instead, GATA4 reduced expression of APNG (alkylpurine-DNA-N-glycosylase), a DNA repair enzyme which is poorly characterized in GBM-mediated temozolomide resistance. Identification and validation of GATA4 as a TSG and its downstream targets in GBM may yield promising novel therapeutic strategies.

A GATA4-regulated tumor suppressor network represses formation of malignant human astrocytomas.

Glioblastome Multiforme (GBM), la tumeur de cerveau humain primaire plus courantes et l&eacute;tale, expose les aberrations mol&eacute;culaires multiples. Les auteurs rapportent que la perte du facteur de transcription GATA4, un r&eacute;gulateur n&eacute;gatif de la prolif&eacute;ration astrocytaire normale, est un pilote en formation de gliome et remplit les caract&eacute;ristiques d&#39;un g&egrave;ne suppresseur de tumeur (STG). Bien que GATA4 a &eacute;t&eacute; exprim&eacute; dans le cerveau normal, perte de GATA4 a &eacute;t&eacute; observ&eacute;e dans des &eacute;chantillons du dispositif de GBM 94/163 et &eacute;tait un marqueur pronostique de survie n&eacute;gatif. GATA4 perte s&#39;est produite gr&acirc;ce &agrave; des mutations somatiques promoteur hyperm&eacute;thylation ou roman. Perte de GATA4 dans les astrocytes humains normaux favoris&eacute; la formation de l&#39;astrocytome de haute qualit&eacute;, en coop&eacute;ration avec d&#39;autres alt&eacute;rations g&eacute;n&eacute;tiques pertinentes tels que Ras activ&eacute; ou perte de TP53. Perte de GATA4 avec Ras activ&eacute;s dans les astrocytes normaux promu un ph&eacute;notype comme g&eacute;niteur, formation de neurospheres et la capacit&eacute; de diff&eacute;rencier dans les astrocytes, neurones et oligodendrocytes. R&eacute;expression du GATA4 dans les lign&eacute;es de cellules humaines de GBM, cultures primaires et cerveau d&eacute;clenchant les tumeurs supprim&eacute;s des cellules tumorales in vitro et in vivo par une activation directe de l&#39;inhibiteur du cycle cellulaire P21(CIP1), ind&eacute;pendant de TP53. R&eacute;expression du GATA4 conf&eacute;r&eacute; &eacute;galement la sensibilit&eacute; des cellules GBM &agrave; t&eacute;mozolomide, un agent alkylant ADN actuellement utilis&eacute; dans la th&eacute;rapie GBM. Cette sensibilit&eacute; est ind&eacute;pendante de MGMT (O-6-m&eacute;thylguanine-ADN-m&eacute;thyltransf&eacute;rase), l&#39;enzyme de r&eacute;paration de l&#39;ADN qui est souvent impliqu&eacute;e dans la r&eacute;sistance de t&eacute;mozolomide. Au lieu de cela, GATA4 r&eacute;duit expression de APNG (alkylpurine-ADN-N-glycosylase), une enzyme de r&eacute;paration d&#39;ADN qui est mal caract&eacute;ris&eacute;e dans la r&eacute;sistance induite par le GBM t&eacute;mozolomide. Identification et validation de GATA4 comme une STG et de ses objectifs en aval dans GBM peuvent donner prometteuses de nouvelles strat&eacute;gies th&eacute;rapeutiques.

Un r&eacute;seau de suppresseur de tumeur r&eacute;glement&eacute;s GATA4 r&eacute;prime formation des astrocytomes humaines malignes.

Glioblastoma Multiforme (GBM), il tumore al cervello umano primario pi&ugrave; comune e letale, esposizioni multiple aberrazioni molecolari. Segnaliamo che perdita del fattore di trascrizione GATA4, un regolatore negativo della proliferazione di astrociti normali, &egrave; un driver nella formazione di glioma e compie i tratti distintivi di un gene soppressore tumorale (STG). Sebbene GATA4 &egrave; stato espresso nel cervello normale, perdita di GATA4 &egrave; stata osservata in 94/163 campioni di GBM operative ed era un indicatore prognostico negativo di sopravvivenza. GATA4 perdita si &egrave; verificata attraverso mutazioni somatiche a promotore ipermetilazione o romanzo. Perdita di GATA4 negli astrociti umani normali promossa formazione di astrocitoma di alto grado, in collaborazione con altre alterazioni genetiche rilevanti quali Ras attivato o perdita di TP53. Perdita di GATA4 con Ras attivato negli astrociti normali promosso un fenotipo progenitore-come formazione di neurospheres e la capacit&agrave; di differenziarsi in astrociti, oligodendrociti e neuroni. Riespressione di GATA4 in linee di cellule umane GBM, colture primarie e cervello tumore-avvio cellule soppresse crescita tumorale in vitro e in vivo mediante attivazione diretta del ciclo cellulare inibitore P21(CIP1), indipendente di TP53. Riespressione di GATA4 conferito anche sensibilit&agrave; delle cellule GBM di temozolomide, un agente alchilante DNA attualmente utilizzata nella terapia di GBM. Questa sensibilit&agrave; era indipendente di MGMT (O-6-metilguanina-DNA-metiltransferasi), l&#39;enzima di riparazione del DNA che &egrave; spesso implicato nella resistenza di temozolomide. Invece, GATA4 ridotta espressione di APNG (alkylpurine-DNA-N-glycosylase), un enzima di riparazione del DNA che &egrave; scarsamente caratterizzato nella resistenza mediata da GBM temozolomide. Identificazione e validazione di GATA4 come un STG e suoi bersagli a valle in GBM pu&ograve; produrre promettenti nuove strategie terapeutiche.

Una rete di soppressore tumorale GATA4-regolato reprime formazione di astrocitomi maligni umani.

Highly proliferating cells, normal or transformed, undergo aerobic glycolysis whereby glucose is metabolized to lactate rather than by oxidative metabolism, even in the presence of oxygen. This metabolic adaptation provides a survival advantage and facilitates synthesis of biosynthetic precursors required for continued cellular proliferation. An important mediator of aerobic glycolysis is our demonstration that in malignant gliomas there is over-expression of the glycolytic enzyme hexokinase 2 (HK2), phosphorylating glucose as the first step of the glycolytic pathway. In contrast, normal brain preferentially expresses HK1 and undergoes oxidative glucose metabolism. In this study, we examine whether this switch in HK isoform also occurs in the developing embryo and central nervous system (CNS). Bioinformatic analysis of available microarray data, including that of The Cancer Genome Atlas, demonstrated a ~17% overlap in metabolic-related genes in blastocyst stage embryo and human GBM tissue, including upregulation of HK2 and downregulation of HK1. Quantitative RT-PCR on mouse brains isolated at different embryonic and postnatal development time-points demonstrated HK2 expression was highest in the early embryo, while HK1 expression increased with CNS maturation. The downstream glycolytic enzymes PKM2 and LDHA had similar temporal profiles as HK2. Expression of the HK2 isoform was due in part to epigenetic regulation of HK2. In support, adult normal human brain and the few human GBM cell lines with low HK2 expression had methylation of CpG islands within intron 1 of HK2. In contrast, developing human fetal brain and GBM tissue expressing HK2 demonstrated significantly lower percent methylation. Furthermore, treatment of GBM cells lacking HK2 with 5-aza-2-deoxycytidine restored HK2 transcript expression. Overall, our results demonstrate that proliferative states including the developing embryo and malignant gliomas, which rely on aerobic glycolysis, preferentially express the HK2 isoform, found to be regulated in part epigenetically.

Developmental profile and regulation of the glycolytic enzyme hexokinase 2 in normal brain and glioblastoma multiforme.

Les cellules en prolif&eacute;ration hautement, normales ou transform&eacute;es, subissent la glycolyse a&eacute;robie par laquelle le glucose est m&eacute;tabolis&eacute; en lactate plut&ocirc;t que par le m&eacute;tabolisme oxydatif, m&ecirc;me en pr&eacute;sence d&#39;oxyg&egrave;ne. Cette adaptation m&eacute;tabolique repr&eacute;sente un avantage de survie et facilite la synth&egrave;se des pr&eacute;curseurs biosynth&eacute;tiques n&eacute;cessaires &agrave; une prolif&eacute;ration cellulaire continue. Un m&eacute;diateur important de la glycolyse a&eacute;robie est notre d&eacute;monstration qu&#39;il y a dans les gliomes malins la surexpression de l&#39;enzyme glycolytique hexokinase 2 (HK2), phosphorylation de glucose comme la premi&egrave;re &eacute;tape de la voie glycolytique. En revanche, le cerveau normal pr&eacute;f&eacute;rentiellement exprime HK1 et subit le m&eacute;tabolisme oxydatif. Dans cette &eacute;tude, nous examinons si ce commutateur dans l&#39;isoforme HK se produit &eacute;galement dans l&#39;embryon et du syst&egrave;me nerveux central (SNC). L&#39;analyse bioinformatique des donn&eacute;es microarray disponibles, y compris celle de The Cancer Genome Atlas, a d&eacute;montr&eacute; un chevauchement d&#39;environ 17 % dans les g&egrave;nes m&eacute;taboliques li&eacute;s &agrave; l&#39;embryon stade blastocyste et de tissus humains de GBM, y compris l&#39;upregulation of HK2 et downregulation de HK1. RT-PCR quantitative sur le cerveau des souris isol&eacute; &agrave; diff&eacute;rents embryonnaires et points dans le temps-d&eacute;veloppement postnatal d&eacute;montrent HK2 expression &eacute;tait la plus &eacute;lev&eacute;e dans l&#39;embryon pr&eacute;coce, tandis que l&#39;expression HK1 augmente avec la maturation de la CNS. En aval enzymes glycolytiques PKM2 et LDHA avaient des profils temporels similaires comme HK2. Expression de l&#39;isoforme HK2 &eacute;tait due en partie &agrave; la r&eacute;gulation &eacute;pig&eacute;n&eacute;tique de la HK2. &Agrave; l&#39;appui, le cerveau humain adult normal et les quelques lign&eacute;es de cellules humaines de GBM avec faible expression HK2 avaient m&eacute;thylation des &icirc;les de CpG au sein de l&#39;intron 1 du HK2. En revanche, d&eacute;velopper le cerveau foetal humain et tissus GBM exprimant HK2 d&eacute;montr&eacute; m&eacute;thylation pourcentage significativement plus faible. En outre, le traitement des cellules GBM manque HK2 avec 5-aza-2-d&eacute;soxycytidine restaur&eacute; HK2 expression de transcription. Dans l&#39;ensemble, nos r&eacute;sultats d&eacute;montrent qu&#39;&Eacute;tats PROLIF&Eacute;RATIFS dont le d&eacute;veloppement embryonnaire et gliomes malins, qui reposent sur la glycolyse a&eacute;robie, pr&eacute;f&eacute;rentiellement expresse l&#39;isoforme HK2, av&eacute;r&eacute; &ecirc;tre r&eacute;gul&eacute;e en partie &eacute;pig&eacute;n&eacute;tique.

Profil de d&eacute;veloppement et de r&eacute;gulation de l&#39;enzyme glycolytique hexokinase 2 en normal multiforme de cerveau et le glioblastome.

Cellule altamente proliferanti, normale o trasformate, subiscono la glicolisi aerobica per cui il glucosio viene metabolizzato lattato piuttosto che dal metabolismo ossidativo, anche in presenza di ossigeno. Questo adattamento metabolico fornisce un vantaggio di sopravvivenza e facilita la sintesi dei precursori necessari per la proliferazione cellulare continua. Un importante mediatore della glicolisi aerobica &egrave; la nostra dimostrazione che nei gliomi maligni &egrave; sovraespressione dell&#39;enzima glicolitico esochinasi 2 (HK2), fosforilante glucosio come il primo passo del pathway glicolitico. Al contrario, cervello normale preferenzialmente esprime HK1 e subisce metabolismo ossidativo del glucosio. In questo studio, esaminiamo se questo interruttore in HK isoforma si verifica anche nell&#39;embrione in via di sviluppo e del sistema nervoso centrale (SNC). L&#39;analisi bioinformatica dei dati di microarray disponibili, tra cui quello di The Cancer Genome Atlas, ha dimostrato una sovrapposizione ~ 17% nei geni metabolici correlati in embrione fase blastocisti e tessuto umano di GBM, compresa la sovraregolazione di HK2 e downregulation di HK1. RT-PCR quantitativa su cervelli di topo isolato a diversa embrionali e tempo-punti di sviluppo postnatale dimostrarono HK2 espressione era pi&ugrave; alto nell&#39;embrione precoce, mentre l&#39;espressione HK1 aumenta con la stagionatura CNS. Gli enzimi glicolitici a valle PKM2 e LDHA avevano simili profili temporali come HK2. Espressione dell&#39;isoforma HK2 era dovuta in parte alla regolazione epigenetica della HK2. Nel supporto, cervello umano adulto normale e le poche righe di cella GBM umane con bassa espressione di HK2 avevano la metilazione delle isole CpG all&#39;interno dell&#39;introne 1 del HK2. Al contrario, lo sviluppo di cervello fetale umano e tessuto GBM esprimendo HK2 dimostrato metilazione percentuale significativamente inferiore. Inoltre, trattamento di cellule GBM manca HK2 con 5-aza-2-deoxycytidine restaurato HK2 espressione di trascrizione. Nel complesso, i nostri risultati dimostrano che proliferativi stati tra cui l&#39;embrione in via di sviluppo e gliomi maligni, che si basano sulla glicolisi aerobica, preferenzialmente espressa l&#39;isoforma HK2, trovano a essere regolato in parte epigeneticamente.

Il profilo dello sviluppo e regolamento dell&#39;enzima glicolitico esochinasi 2 in normale cervello e glioblastoma multiforme.

Glioblastoma multiforme (GBM) &egrave; il pi&ugrave; comune e letale di tutti i gliomi. L&#39;attuale standard di cura comprende la chirurgia seguita dalla concomitante radiazione e la chemioterapia con il DNA agente alchilante temozolomide (TMZ). O&#x2076;-metilguanina-DNA metiltransferasi (MGMT) ripara il pi&ugrave; citotossici delle lesioni generate da TMZ, O&#x2076;-metilguanina. Metilazione del promotore MGMT in GBM correla con maggiore sensibilit&agrave; terapeutica di alchilanti terapia agente. Tuttavia, alcuni aspetti della sensibilit&agrave; TMZ non sono spiegati da metilazione del promotore MGMT. Qui, abbiamo studiato la nostra ipotesi che la base escissione riparazione enzima alkylpurine-DNA-N-glycosylase (APNG), che ripara le lesioni citotossiche N&sup3;-polymerase e N&#x2077;-metilguanina, pu&ograve; contribuire alla resistenza di TMZ. Silenziamento di APNG in stabilito e primarie linee di cellule GBM TMZ-resistente endogena che esprimono MGMT e APNG attenuato di riparazione dei danni al DNA indotti da TMZ ed enhanced apoptosi. Reintrodurre la espressione di APNG nelle linee di TMZ-sensibili GBM conferito resistenza a TMZ in vitro e in modelli murini di ortotopico xenoinnesto. Inoltre, &egrave; stata migliorata resistenza con coexpression della proteina Mgmt. valutazione di APNG livelli in diversi set di dati clinici hanno dimostrato che nei pazienti, alta espressione nucleare APNG correlata con pi&ugrave; povero sopravvivenza complessiva rispetto ai pazienti privi di espressione APNG. Perdita di espressione APNG in un sottogruppo di pazienti era anche associato con maggiore metilazione di promotore APNG. Collettivamente, i nostri dati dimostrano che APNG contribuisce alla resistenza di TMZ in GBM e pu&ograve; essere utile nella diagnosi e nel trattamento della malattia.

Alkylpurine-DNA-N-glycosylase conferisce resistenza a temozolomide in modelli xenoinnesto di glioblastoma multiforme ed &egrave; associata a scarsa sopravvivenza nei pazienti.

&#x591A;&#x5F62;&#x6027;&#x80F6;&#x8D28;&#x6BCD;&#x7EC6;&#x80DE;&#x7624; (GBM) &#x662F;&#x6700;&#x5E38;&#x89C1;&#x548C;&#x6700;&#x81F4;&#x547D;&#x7684;&#x6240;&#x6709;&#x80F6;&#x8D28;&#x7624;&#x3002;&#x76EE;&#x524D;&#x6807;&#x51C6;&#x7684;&#x62A4;&#x7406;&#x5305;&#x62EC;&#x624B;&#x672F;&#x540E;&#x63A5;&#x53D7;&#x968F;&#x4E4B;&#x800C;&#x6765;&#x7684;&#x8F90;&#x5C04;&#x548C; DNA &#x70F7;&#x4EE3;&#x7406;&#x66FF;&#x83AB;&#x5511;&#x80FA; &#xFF08;TMZ) &#x5316;&#x7597;&#x3002;O&#x2076;-methylguanine-DNA &#x7532;&#x57FA;&#x8F6C;&#x79FB;&#x9176; (MGMT) &#x4FEE;&#x590D;&#x6700;&#x6BD2;&#x7684; TMZ&#xFF0C;O&#x2076; methylguanine &#x7531;&#x751F;&#x6210;&#x7684;&#x75C5;&#x53D8;&#x3002;&#x5927;&#x7D2B;&#x8346;&#x52CB;&#x8D24; MGMT &#x542F;&#x52A8;&#x5B50;&#x7532;&#x57FA;&#x5316;&#x4E0E;&#x5316;&#x5242;&#x5242;&#x6CBB;&#x7597;&#x66F4;&#x591A;&#x6CBB;&#x7597;&#x654F;&#x611F;&#x6027;&#x7684;&#x5173;&#x8054;&#x3002;&#x7136;&#x800C;&#xFF0C;MGMT &#x542F;&#x52A8;&#x5B50;&#x7532;&#x57FA;&#x5316;&#x4E0D;&#x89E3;&#x91CA; TMZ &#x7075;&#x654F;&#x5EA6;&#x7684;&#x51E0;&#x4E2A;&#x65B9;&#x9762;&#x3002;&#x5728;&#x8FD9;&#x91CC;&#xFF0C;&#x6211;&#x4EEC;&#x8C03;&#x67E5;&#x6211;&#x4EEC;&#x57FA;&#x5730;&#x7684;&#x5207;&#x9664;&#x4FEE;&#x590D;&#x7CD6;&#x82F7;&#x9176; alkylpurine-DNA-N-&#x9176; (APNG) &#x4FEE;&#x590D;&#x7EC6;&#x80DE;&#x6BD2;&#x75C5;&#x53D8; N&sup3; methyladenine &#x548C; N&#x2077; methylguanine&#xFF0C;&#x53EF;&#x80FD;&#x6709;&#x52A9;&#x4E8E; TMZ &#x62B5;&#x6297;&#x7684;&#x5047;&#x8BF4;&#x3002;&#x6C89;&#x9ED8;&#x7684;&#x5728; APNG &#x8BBE;&#x7ACB;&#x548C;&#x4E3B; TMZ &#x8010;&#x5927;&#x7D2B;&#x8346;&#x52CB;&#x8D24;&#x7EC6;&#x80DE;&#x682A;&#x6B65;&#x4E4B;&#x9065;&#x8868;&#x793A;&#x7BA1;&#x7406;&#x548C; APNG &#x51CF;&#x6BD2; TMZ &#x8BF1;&#x5BFC;&#x7684; DNA &#x635F;&#x4F24;&#x7684;&#x4FEE;&#x590D;&#x548C;&#x589E;&#x5F3A;&#x7EC6;&#x80DE;&#x51CB;&#x4EA1;&#x3002;&#x4F01;&#x671B; APNG TMZ &#x654F;&#x611F;&#x5927;&#x7D2B;&#x8346;&#x52CB;&#x8D24;&#x884C;&#x4E2D;&#x7684;&#x8868;&#x8FBE;&#x5F0F;&#x8D4B;&#x4E88;&#x62B5;&#x6297; TMZ &#x4F53;&#x5916;&#xFF0C;&#x5E76;&#x5728;&#x539F;&#x4F4D;&#x5F02;&#x79CD;&#x79FB;&#x690D;&#x5C0F;&#x9F20;&#x6A21;&#x578B;&#x3002;&#x6B64;&#x5916;&#xFF0C;&#x4E0E; APNG &#x7BA1;&#x7406;&#x8BC4;&#x4EF7;&#x86CB;&#x767D;&#x8D28;&#x6C34;&#x5E73;&#x7684;&#x51E0;&#x4E2A;&#x4E34;&#x5E8A;&#x6570;&#x636E;&#x96C6;&#x8868;&#x660E;&#x60A3;&#x8005;&#xFF0C;&#x9AD8;&#x6838; APNG &#x8868;&#x8FBE;&#x4E0E;&#x60A3;&#x8005;&#x7F3A;&#x4E4F; APNG &#x8868;&#x8FBE;&#x6BD4;&#x8F83;&#x7A77;&#x603B;&#x4F53;&#x751F;&#x5B58;&#x76F8;&#x5173;&#x7684;&#x5171;&#x8868;&#x8FBE;&#x52A0;&#x5F3A;&#x4E86;&#x62B5;&#x6297;&#x3002;&#x635F;&#x5931; APNG &#x8868;&#x8FBE;&#x7684;&#x4E00;&#x4E2A;&#x5B50;&#x96C6;&#x7684;&#x60A3;&#x8005;&#x4E5F;&#x589E;&#x52A0; APNG &#x542F;&#x52A8;&#x5B50;&#x7532;&#x57FA;&#x5316;&#x4E0E;&#x76F8;&#x5173;&#x8054;&#x3002;&#x96C6;&#x4F53;&#xFF0C;&#x6211;&#x4EEC;&#x7684;&#x6570;&#x636E;&#x8868;&#x660E; APNG &#x6709;&#x52A9;&#x4E8E; TMZ &#x62B5;&#x6297;&#x7684;&#x5927;&#x7D2B;&#x8346;&#x52CB;&#x8D24;&#xFF0C;&#x53EF;&#x80FD;&#x6709;&#x7528;&#x7684;&#x8BCA;&#x65AD;&#x548C;&#x6CBB;&#x7597;&#x8BE5;&#x75BE;&#x75C5;&#x7684;&#x3002;

Alkylpurine-DNA-N-&#x7CD6;&#x82F7;&#x9176;&#x8D4B;&#x4E88;&#x5F02;&#x79CD;&#x79FB;&#x690D;&#x6A21;&#x578B;&#x7684;&#x591A;&#x5F62;&#x6027;&#x80F6;&#x8D28;&#x6BCD;&#x7EC6;&#x80DE;&#x7624;&#x66FF;&#x83AB;&#x5511;&#x80FA;&#x6297;&#x6027;&#x548C;&#x5173;&#x8054;&#x4E0D;&#x826F;&#x60A3;&#x8005;&#x7684;&#x5B58;&#x6D3B;&#x7387;&#x3002;

Glioblastoma multiforme (GBM) is the most common and lethal of all gliomas. The current standard of care includes surgery followed by concomitant radiation and chemotherapy with the DNA alkylating agent temozolomide (TMZ). Oâ¶-methylguanine-DNA methyltransferase (MGMT) repairs the most cytotoxic of lesions generated by TMZ, Oâ¶-methylguanine. Methylation of the MGMT promoter in GBM correlates with increased therapeutic sensitivity to alkylating agent therapy. However, several aspects of TMZ sensitivity are not explained by MGMT promoter methylation. Here, we investigated our hypothesis that the base excision repair enzyme alkylpurine-DNA-N-glycosylase (APNG), which repairs the cytotoxic lesions NÂ³-methyladenine and Nâ·-methylguanine, may contribute to TMZ resistance. Silencing of APNG in established and primary TMZ-resistant GBM cell lines endogenously expressing MGMT and APNG attenuated repair of TMZ-induced DNA damage and enhanced apoptosis. Reintroducing expression of APNG in TMZ-sensitive GBM lines conferred resistance to TMZ in vitro and in orthotopic xenograft mouse models. In addition, resistance was enhanced with coexpression of MGMT. Evaluation of APNG protein levels in several clinical datasets demonstrated that in patients, high nuclear APNG expression correlated with poorer overall survival compared with patients lacking APNG expression. Loss of APNG expression in a subset of patients was also associated with increased APNG promoter methylation. Collectively, our data demonstrate that APNG contributes to TMZ resistance in GBM and may be useful in the diagnosis and treatment of the disease.

Alkylpurine-DNA-N-glycosylase confers resistance to temozolomide in xenograft models of glioblastoma multiforme and is associated with poor survival in patients.

Glioblastome multiforme (GBM) est le plus fr&eacute;quent et le plus mortel de tous les gliomes. La norme actuelle de soins comprend la chirurgie suivie d&#39;un rayonnement concomitant et chimioth&eacute;rapie avec l&#39;ADN alkylant agent t&eacute;mozolomide (TMZ). O&#x2076;-m&eacute;thylguanine ADN m&eacute;thyltransf&eacute;rase (MGMT) r&eacute;pare les plus cytotoxique des l&eacute;sions g&eacute;n&eacute;r&eacute;es par TMZ, O&#x2076;-m&eacute;thylguanine. La m&eacute;thylation du promoteur MGMT dans GBM est en corr&eacute;lation avec une sensibilit&eacute; th&eacute;rapeutique accrue aux alkylants th&eacute;rapie d&#39;agent. Cependant, plusieurs aspects de la sensibilit&eacute; TMZ ne sont pas expliqu&eacute;es par m&eacute;thylation du promoteur MGMT. Ici, nous avons &eacute;tudi&eacute; notre hypoth&egrave;se que la base excision r&eacute;paration enzymatique alkylpurine-ADN-N-glycosylase (APNG), qui r&eacute;pare les l&eacute;sions cytotoxiques N&sup3;-m&eacute;thylad&eacute;nine et N&#x2077;-m&eacute;thylguanine, peut contribuer &agrave; la r&eacute;sistance de TMZ. Silencing of APNG en &eacute;tabli et des lign&eacute;es de cellules r&eacute;sistant &agrave; la TMZ GBM primaires endog&egrave;ne exprimant MGMT et APNG a att&eacute;nu&eacute; la r&eacute;paration des l&eacute;sions de l&#39;ADN induite par TMZ et am&eacute;lior&eacute; l&#39;apoptose. R&eacute;introduire l&#39;expression de APNG en lignes sensibles TMZ GBM conf&eacute;r&eacute; r&eacute;sistance &agrave; TMZ in vitro et dans des mod&egrave;les de souris x&eacute;nogreffes orthotopiques. En outre, la r&eacute;sistance est accrue coexpression de prot&eacute;ine Mgmt. &eacute;valuation du APNG niveaux dans plusieurs ensembles de donn&eacute;es cliniques a d&eacute;montr&eacute; que chez les patients, haute expression nucl&eacute;aire de APNG en corr&eacute;lation avec la survie globale plus faible compar&eacute;e aux patients d&eacute;pourvus d&#39;expression APNG. Perte d&#39;expression APNG dans un sous-ensemble de patients &eacute;tait &eacute;galement associ&eacute;e de la m&eacute;thylation du promoteur APNG accrue. Collectivement, nos r&eacute;sultats d&eacute;montrent que APNG contribue &agrave; la r&eacute;sistance de TMZ en GBM et peut &ecirc;tre utile dans le diagnostic et le traitement de la maladie.

Alkylpurine-ADN-N-glycosylase conf&egrave;re la r&eacute;sistance au t&eacute;mozolomide dans des mod&egrave;les de x&eacute;nogreffes de glioblastome multiforme et est associ&eacute; &agrave; faible taux de survie chez les patients.

Glioblastoma Multiforme (GBM) ist die h&auml;ufigsten und t&ouml;dliche alle Gliome. Der aktuelle Standard-Behandlung umfasst Operation gefolgt von begleitenden Strahlen- und Chemotherapie mit der DNA alkylierenden Agent Temozolomid (TMZ). O&#x2076;-Methylguanin-DNA-Methyltransferase (MGMT) repariert die meisten zytotoxischen L&auml;sionen von TMZ, O&#x2076;-Methylguanin generiert. Methylierung des Promotors MGMT in GBM korreliert mit therapeutischen empfindlicher auf Alkylantien Agent-Therapie. Jedoch sind einige Aspekte der TMZ Empfindlichkeit nicht durch MGMT-Promotor-Methylierung erkl&auml;rt. Hier untersuchten wir unsere Hypothese, dass die base Exzision Enzym Alkylpurine-DNA-N-Glycosylase (APNG), die repariert die zytotoxischen L&auml;sionen N&sup3;-Methyladenine und N&#x2077;-Methylguanin reparieren, kann dazu beitragen, TMZ Widerstand. Unterdr&uuml;ckender von APNG in gegr&uuml;ndet und prim&auml;re TMZ-resistenten GBM-Zelllinien, die endogen Ausdruck von MGMT und APNG abgeschw&auml;cht TMZ-induzierten DNA-Sch&auml;den zu reparieren und Apoptosis. Wiedereinf&uuml;hrung der Ausdruck der APNG in TMZ-Sensitive GBM Linien &uuml;bertragenen TMZ in-vitro-und in Orthotopic Xenograft-Mausmodelle. Dar&uuml;ber hinaus war Widerstand mit Coexpression Mgmt. Bewertung von APNG Protein erh&ouml;ht Ebenen in mehreren klinischen Datasets gezeigt, dass bei Patienten, hohe nukleare APNG-Ausdruck mit &auml;rmeren die Gesamt&uuml;berlebenszeit gegen&uuml;ber Patienten fehlt APNG Ausdruck korreliert. Verlust von APNG Ausdruck in einer Untergruppe von Patienten wurde auch erh&ouml;hte APNG-Promotor-Methylierung zugeordnet. Zusammenfassend zeigen unsere Daten, dass APNG zur TMZ-Resistenz bei GBM tr&auml;gt und kann n&uuml;tzlich in der Diagnose und Behandlung der Krankheit sein.

Alkylpurine-DNA-N-Glycosylase verleiht Resistenz gegen Temozolomid in Xenograft-Modelle von Glioblastoma Multiforme und Armen &Uuml;berleben bei Patienten zugeordnet ist.

&#x81A0; &#xFF08;GBM&#xFF09; &#x306F;&#x3001;&#x6700;&#x3082;&#x4E00;&#x822C;&#x7684;&#x3067;&#x3059;&#x3079;&#x3066;&#x306E;&#x795E;&#x7D4C;&#x81A0;&#x816B;&#x306E;&#x81F4;&#x547D;&#x7684;&#x306A;&#x3067;&#x3059;&#x3002;&#x4ECB;&#x8B77;&#x306E;&#x73FE;&#x5728;&#x306E;&#x6A19;&#x6E96;&#x306B;&#x7D9A;&#x304F;&#x4F75;&#x7528;&#x653E;&#x5C04;&#x7DDA;&#x304A;&#x3088;&#x3073;&#x5316;&#x5B66;&#x7642;&#x6CD5; DNA &#x30A2;&#x30EB;&#x30AD;&#x30EB;&#x5316;&#x5264;&#x30C6;&#x30E2;&#x30BE;&#x30ED;&#x30DF;&#x30C9; (TMZ) &#x3068;&#x624B;&#x8853;&#x304C;&#x542B;&#x307E;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;O&#x2076;-&#x30E1;&#x30C1;&#x30EB;&#x30B0;&#x30A2;&#x30CB;&#x30F3;&#x6E2C;&#x5B9A; DNA &#x30E1;&#x30C1;&#x30EB;&#x30C8;&#x30E9;&#x30F3;&#x30B9;&#x30D5;&#x30A7;&#x30E9;&#x30FC;&#x30BC; (MGMT) &#x6700;&#x3082; O&#x2076;-&#x30E1;&#x30C1;&#x30EB;&#x30B0;&#x30A2;&#x30CB;&#x30F3;&#x6E2C;&#x5B9A; TMZ &#x306B;&#x3088;&#x3063;&#x3066;&#x751F;&#x6210;&#x3055;&#x308C;&#x305F;&#x75C5;&#x5909;&#x306E;&#x7D30;&#x80DE;&#x6BD2;&#x6027;&#x3092;&#x4FEE;&#x5FA9;&#x3057;&#x307E;&#x3059;&#x3002;&#x7CF8;&#x7403;&#x4F53;&#x57FA;&#x5E95;&#x819C;&#x306B;&#x304A;&#x3051;&#x308B; MGMT &#x30D7;&#x30ED;&#x30E2;&#x30FC;&#x30BF;&#x30FC;&#x306E;&#x30E1;&#x30C1;&#x30EB;&#x5316;&#x30A2;&#x30EB;&#x30AD;&#x30EB;&#x5316;&#x5264;&#x6CBB;&#x7642;&#x306B;&#x6CBB;&#x7642;&#x611F;&#x5EA6;&#x306E;&#x5411;&#x4E0A;&#x3068;&#x95A2;&#x9023;&#x4ED8;&#x3051;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x305F;&#x3060;&#x3057;&#x3001;&#x3044;&#x304F;&#x3064;&#x304B;&#x306E;&#x5074;&#x9762; TMZ &#x611F;&#x5EA6; MGMT &#x30D7;&#x30ED;&#x30E2;&#x30FC;&#x30BF;&#x30FC;&#x306E;&#x30E1;&#x30C1;&#x30EB;&#x5316;&#x306B;&#x3088;&#x3063;&#x3066;&#x8AAC;&#x660E;&#x3067;&#x304D;&#x307E;&#x305B;&#x3093;&#x3002;&#x3053;&#x3053;&#x3067;&#x306F;&#x3001;&#x6211;&#x3005; &#x306E;&#x4EEE;&#x8AAC;&#x306E;&#x5869;&#x57FA;&#x9664;&#x53BB;&#x9175;&#x7D20; alkylpurine-DNA-N - &#x4FEE;&#x7406;&#x7D30;&#x80DE;&#x6BD2;&#x6027;&#x75C5;&#x5909; N&sup3;-&#x30E1;&#x30C1;&#x30EB;&#x30A2;&#x30C7;&#x30CB;&#x30F3;&#x3068; N&#x2077;-&#x30E1;&#x30C1;&#x30EB;&#x30B0;&#x30A2;&#x30CB;&#x30F3;&#x6E2C;&#x5B9A;&#x3001;TMZ &#x62B5;&#x6297;&#x306B;&#x8CA2;&#x732E;&#x3059;&#x308B;&#x304B;&#x3082;&#x3057;&#x308C;&#x306A;&#x3044;&#x30B0;&#x30EA;&#x30B3;&#x30B7;&#x30E9;&#x30FC;&#x30BC; (APNG) &#x3092;&#x4FEE;&#x5FA9;&#x3059;&#x308B;&#x3053;&#x3068;&#x3092;&#x691C;&#x8A0E;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x30B3;&#x30CD;&#x304C; APNG &#x306E;&#x30B5;&#x30A4;&#x30EC;&#x30F3;&#x30B7;&#x30F3;&#x30B0;&#x306E;&#x78BA;&#x7ACB;&#x3068;&#x5185;&#x751F;&#x7684; MGMT &#x3068;&#x5F31;&#x6BD2; APNG &#x3092;&#x8868;&#x73FE;&#x3059;&#x308B;&#x30D7;&#x30E9;&#x30A4;&#x30DE;&#x30EA; TMZ &#x8010;&#x6027; GBM &#x30BB;&#x30EB;&#x30E9;&#x30A4;&#x30F3; TMZ &#x306B;&#x3088;&#x308B; DNA &#x640D;&#x50B7;&#x306E;&#x4FEE;&#x5FA9;&#x3057;&#x30A2;&#x30DD;&#x30C8;&#x30FC;&#x30B7;&#x30B9;&#x3092;&#x5F37;&#x5316;&#x3057;&#x307E;&#x3059;&#x3002;TMZ &#x306B;&#x654F;&#x611F;&#x306A; GBM &#x7DDA;&#x306B;&#x304A;&#x3051;&#x308B; APNG &#x306E;&#x767A;&#x73FE;&#x3092; reintroducing &#x3068;&#x76F4;&#x4EA4;&#x7570;&#x65B9;&#x6027;&#x7570;&#x7A2E;&#x79FB;&#x690D;&#x30DE;&#x30A6;&#x30B9; &#x30E2;&#x30C7;&#x30EB;&#x3067; TMZ &#x4F53;&#x5916;&#x3078;&#x306E;&#x62B5;&#x6297;&#x3092;&#x6388;&#x4E0E;&#x3057;&#x307E;&#x3057;&#x305F;&#x3002;&#x3055;&#x3089;&#x306B;&#x3001;&#x60A3;&#x8005;&#x3067;&#x306F;&#x3001;&#x6838; APNG &#x5F0F;&#x9AD8; APNG &#x5F0F;&#x6B20;&#x3051;&#x3066;&#x3044;&#x308B;&#x60A3;&#x8005;&#x3068;&#x6BD4;&#x8F03;&#x3057;&#x3066;&#x5168;&#x4F53;&#x7684;&#x306A;&#x4E88;&#x5F8C;&#x3068;&#x76F8;&#x95A2;&#x3059;&#x308B;&#x3053;&#x3068;&#x81E8;&#x5E8A;&#x306E;&#x8907;&#x6570;&#x306E;&#x30C7;&#x30FC;&#x30BF;&#x30BB;&#x30C3;&#x30C8;&#x5185;&#x306E;&#x30EC;&#x30D9;&#x30EB;&#x3092;&#x793A;&#x3057;&#x305F;&#x7BA1;&#x7406; APNG &#x8A55;&#x4FA1;&#x86CB;&#x767D;&#x8CEA;&#x306E;&#x767A;&#x73FE;&#x3068;&#x62B5;&#x6297;&#x304C;&#x5F37;&#x5316;&#x3055;&#x308C;&#x307E;&#x3057;&#x305F;&#x3002;&#x60A3;&#x8005;&#x306E;&#x30B5;&#x30D6;&#x30BB;&#x30C3;&#x30C8;&#x3067; APNG &#x5F0F;&#x306E;&#x640D;&#x5931;&#x3082;&#x5897;&#x52A0; APNG &#x30D7;&#x30ED;&#x30E2;&#x30FC;&#x30BF;&#x30FC;&#x306E;&#x30E1;&#x30C1;&#x30EB;&#x5316;&#x3068;&#x95A2;&#x9023;&#x4ED8;&#x3051;&#x3089;&#x308C;&#x3066;&#x3044;&#x305F;&#x3002;&#x4EE5;&#x4E0B;&#x3001;&#x7DCF;&#x79F0;&#x3057;&#x3066;&#x6211;&#x3005; &#x306E;&#x30C7;&#x30FC;&#x30BF; APNG &#x306F; TMZ &#x62B5;&#x6297; GBM &#x306E;&#x8CA2;&#x732E;&#x3057;&#x3001;&#x8A3A;&#x65AD;&#x3068;&#x75C5;&#x6C17;&#x306E;&#x6CBB;&#x7642;&#x306B;&#x5F79;&#x7ACB;&#x3064;&#x3053;&#x3068;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3092;&#x793A;&#x3057;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

Alkylpurine DNA N &#x30B0;&#x30EA;&#x30B3;&#x30B7;&#x30E9;&#x30FC;&#x30BC; xenograft &#x30E2;&#x30C7;&#x30EB;&#x306F;&#x795E;&#x7D4C;&#x81A0;&#x816B;&#x306E;&#x30C6;&#x30E2;&#x30BE;&#x30ED;&#x30DE;&#x30A4;&#x30C9;&#x306B;&#x5BFE;&#x3059;&#x308B;&#x8010;&#x6027;&#x3057;&#x3001;&#x8CA7;&#x3057;&#x3044;&#x4EBA;&#x3005; &#x306E;&#x751F;&#x5B58;&#x60A3;&#x8005;&#x306B;&#x95A2;&#x9023;&#x4ED8;&#x3051;&#x3089;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;

Glioblastoma &#xB2D8; (GBM)&#xC740; &#xAC00;&#xC7A5; &#xC77C;&#xBC18;&#xC801;&#xC774; &#xACE0; &#xBAA8;&#xB4E0; gliomas&#xC758; &#xCE58;&#xBA85;&#xC801;&#xC778;. &#xD604;&#xC7AC; &#xD45C;&#xC900; &#xCE58;&#xB8CC;&#xC758; &#xC218;&#xC220; &#xB4A4;&#xC5D0; &#xC218; &#xBC18;&#xD558;&#xB294; &#xBC29;&#xC0AC;&#xC120; &#xBC0F; &#xD654;&#xD559; &#xC694;&#xBC95; DNA alkylating &#xC5D0;&#xC774;&#xC804;&#xD2B8; temozolomide (TMZ)&#xC640; &#xD568;&#xAED8; &#xD3EC;&#xD568; &#xB429;&#xB2C8;&#xB2E4;. O&#x2076;-methylguanine-DNA methyltransferase (MGMT) TMZ, O&#x2076;-methylguanine&#xC5D0; &#xC758;&#xD574; &#xC0DD;&#xC131; &#xB41C; &#xBCD1; &#xBCC0;&#xC758; &#xAC00;&#xC7A5; cytotoxic &#xBCF5;&#xAD6C; &#xD569;&#xB2C8;&#xB2E4;. GBM&#xC5D0;&#xC11C; MGMT &#xBC1C;&#xAE30;&#xC778;&#xC758; &#xBA54; &#xD2F8; &#xD654; &#xC5D0;&#xC774;&#xC804;&#xD2B8; &#xCE58;&#xB8CC; alkylating &#xC99D;&#xAC00; &#xCE58;&#xB8CC; &#xAC10;&#xB3C4;&#xC640; &#xC5F0;&#xAD00; &#xC2DC;&#xD0B5;&#xB2C8;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098; TMZ &#xAC10;&#xB3C4;&#xC758; &#xC5EC;&#xB7EC; &#xCE21;&#xBA74;&#xC740; MGMT &#xBC1C;&#xAE30;&#xC778; &#xBA54; &#xD2F8; &#xD654;&#xC5D0; &#xC758;&#xD574; &#xC124;&#xBA85; &#xB418;&#xC9C0;. &#xC5EC;&#xAE30;, &#xC6B0;&#xB9AC;&#xAC00; &#xC6B0;&#xB9AC;&#xC758; &#xAC00;&#xC124; &#xAE30;&#xBCF8; &#xC808;&#xB2E8; &#xBCF5;&#xAD6C; &#xD6A8;&#xC18C; alkylpurine-DNA-N-glycosylase (APNG) cytotoxic &#xC7A5;&#xC560; N&sup3; methyladenine &#xBC0F; N&#x2077; methylguanine &#xC218;&#xB9AC;, TMZ &#xC800;&#xD56D;&#xC5D0; &#xAE30;&#xC5EC;&#xD560; &#xC218; &#xC788;&#xB294; &#xC870;&#xC0AC;. &#xC124;&#xB9BD;&#xC5D0; APNG&#xC758; &#xC785;&#xC744; TMZ &#xB0B4;&#xC131; GBM &#xC140; &#xC120; &#xC8FC; endogenously MGMT&#xC640; &#xAC10;&#xC1E0; APNG &#xD45C;&#xD604; TMZ &#xC720;&#xBC1C; DNA &#xC190;&#xC0C1;&#xC758; &#xC218;&#xB9AC; &#xACE0; apoptosis&#xB97C; &#xD5A5;&#xC0C1;. TMZ&#xC5D0; &#xBBFC;&#xAC10;&#xD55C; GBM &#xB77C;&#xC778;&#xC5D0;&#xC11C; APNG&#xC758; &#xC2DD;&#xC744; &#xB2E4;&#xC2DC; &#xC800;&#xD56D; &#xCCB4; &#xC678; TMZ&#xC640; orthotopic &#xB1CC;&#xC885;&#xC591; &#xB9C8;&#xC6B0;&#xC2A4; &#xBAA8;&#xB378;&#xC5D0; &#xAC8C; &#xC218; &#xC5EC;. &#xB610;&#xD55C;, &#xC800;&#xD56D; &#xAD00;&#xB9AC; &#xD3C9;&#xAC00; APNG &#xB2E8;&#xBC31;&#xC9C8; &#xC218;&#xC900;&#xC5D0;&#xC11C; &#xC5EC;&#xB7EC; &#xAC00;&#xC9C0; &#xC784;&#xC0C1; &#xB370;&#xC774;&#xD130; &#xC9D1;&#xD569; &#xC785;&#xC99D; &#xD658;&#xC790;, &#xAC00;&#xB09C;&#xD55C; &#xC804;&#xBC18;&#xC801;&#xC778; &#xC0DD;&#xC874; APNG &#xC2DD; &#xBD80;&#xC871; &#xD55C; &#xD658;&#xC790;&#xC5D0; &#xBE44;&#xD574; &#xB192;&#xC740; &#xD575; APNG &#xC2DD; &#xC0C1;&#xAD00; &#xADF8;&#xC758; coexpression&#xC73C;&#xB85C; &#xD5A5;&#xC0C1; &#xB418;&#xC5C8;&#xC2B5;&#xB2C8;&#xB2E4;. &#xD658;&#xC790;&#xC758; &#xD558;&#xC704; &#xC9D1;&#xD569;&#xC5D0;&#xC11C; APNG &#xC2DD;&#xC758; &#xC190;&#xC2E4; &#xB610;&#xD55C; &#xC99D;&#xAC00; APNG &#xBC1C;&#xAE30;&#xC778; &#xBA54; &#xD2F8; &#xD654;&#xC640; &#xC5F0;&#xAD00; &#xB418;&#xC5C8;&#xB2E4;. &#xD1B5;&#xCE6D; &#xD558; &#xC5EC; &#xC6B0;&#xB9AC;&#xC758; &#xB370;&#xC774;&#xD130; &#xBCF4;&#xC5EC; APNG GBM TMZ &#xC800;&#xD56D;&#xC5D0; &#xAE30;&#xC5EC; &#xD558; &#xACE0; &#xC9C4;&#xB2E8; &#xBC0F; &#xC9C8;&#xBCD1;&#xC758; &#xCE58;&#xB8CC;&#xC5D0; &#xC720;&#xC6A9;&#xD560; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

Alkylpurine-DNA-N-glycosylase temozolomide glioblastoma &#xB2D8;&#xC758; &#xB1CC;&#xC885;&#xC591; &#xBAA8;&#xB378;&#xC5D0;&#xC11C;&#xC5D0; &#xB300; &#xD55C; &#xC800;&#xD56D;&#xC744; &#xC218; &#xC5EC; &#xD558; &#xACE0; &#xAC00;&#xB09C;&#xD55C; &#xC0DD;&#xC874; &#xD658;&#xC790;&#xC5D0; &#xC5F0;&#xAD00; &#xB41C;.

Glioblastoma multiforme (GBM) es el m&aacute;s com&uacute;n y mortal de todos los gliomas. El est&aacute;ndar actual de tratamiento incluye cirug&iacute;a seguida de radiaci&oacute;n concomitante y la quimioterapia con el ADN alquilante agente temozolomida (TMZ). O&#x2076;-metilguanina-DNA metiltransferasa (MGMT) repara el m&aacute;s citot&oacute;xico de lesiones generadas por TMZ, O&#x2076;-metilguanina. Metilaci&oacute;n del promotor MGMT en GBM se correlaciona con el aumento de la sensibilidad terap&eacute;utico a alquilantes terapia del agente. Sin embargo, varios aspectos de la sensibilidad TMZ no se explican por la metilaci&oacute;n del promotor MGMT. Aqu&iacute;, investigamos la hip&oacute;tesis que la supresi&oacute;n de la base reparar la enzima alkylpurine-DNA-N-glicosilasa (APNG), que repara las lesiones citot&oacute;xicas N&sup3;-methyladenine y N&#x2077;-metilguanina, puede contribuir a la resistencia de TMZ. Silenciamiento de APNG en establecido y primarias l&iacute;neas celulares GBM TMZ-resistente end&oacute;geno expresando MGMT y APNG atenuada la reparaci&oacute;n del da&ntilde;o de la DNA inducida por TMZ y mejorado apoptosis. Reintroducci&oacute;n de la expresi&oacute;n de APNG en l&iacute;neas GBM sensible a TMZ conferido resistencia a TMZ in vitro y en modelos de rat&oacute;n de xenoinjerto ortot&oacute;pico. Adem&aacute;s, la resistencia fue realzada con coexpresi&oacute;n de prote&iacute;na Mgmt. evaluaci&oacute;n de APNG niveles en varios conjuntos de datos cl&iacute;nicos demostraron que en pacientes, alta expresi&oacute;n nuclear de APNG correlacionados con peor supervivencia en comparaci&oacute;n con pacientes que carecen de expresi&oacute;n APNG. P&eacute;rdida de expresi&oacute;n de APNG en un subconjunto de pacientes tambi&eacute;n se asoci&oacute; con mayor metilaci&oacute;n del promotor APNG. En conjunto, nuestros datos demuestran que APNG contribuye a la resistencia de TMZ en GBM y puede ser &uacute;til en el diagn&oacute;stico y tratamiento de la enfermedad.

Alkylpurine-DNA-N-glicosilasa confiere resistencia a la temozolomida en modelos de xenoinjerto de glioblastoma multiforme y se asocia a la pobre supervivencia en los pacientes.

Vestibular schwannomas (VS) are a common posterior fossa brain tumor, and though benign can cause significant morbidity, particularly loss of hearing, tinnitus, vertigo and facial paralysis. The current treatment options for VS include microsurgical resection, stereotactic radiosurgery or close surveillance monitoring, with each treatment option carrying associated complications and morbidities. Most importantly, none of these options can definitively reverse hearing loss or tinnitus. Identification of a novel medical therapy, through the use of targeted molecular inhibition, is therefore a highly desirable treatment strategy that may minimize complications arising from both tumor and treatment and more importantly be suitable for patients whose options are limited with respect to surgical or radiosurgical interventions. In this study we chose to examine the effect of Nilotinib on VS. Nilotinib (TasignaÂ®) is a second-generation receptor tyrosine kinase (RTK) inhibitor with a target profile similar to that of imatinib (GleevecÂ®), but increased potency, decreased toxicity and greater cellular and tissue penetration. Nilotinib targets not only the BCR-ABL oncoprotein, but also platelet-derived growth factor (PDGF) receptor signalling. In this preclinical study, the human NF2-null schwannoma cell line HEI-193 subjected to nilotinib inhibition demonstrated decreased viability, proliferation and anchorage-independent growth, and increased apoptosis. A daily dose of nilotinib for 5 days inhibited HEI-I93 proliferation at a clinically-relevant concentration in a dose-dependent manner (IC(50) 3-5 Âµmol/L) in PDGF-stimulated cells. These anti-tumorigenic effects of nilotinib were correlated to inhibited activation of PDGFR-Î± and PDGFR-Î² and major downstream signalling pathways. These experiments support a therapeutic potential for Nilotinib in VS.

Investigation of the in vitro therapeutic efficacy of nilotinib in immortalized human NF2-null vestibular schwannoma cells.

Schwannomes vestibulaires (VS) sont une tumeur au cerveau commun fosse post&eacute;rieure et bien que b&eacute;nigne peuvent entra&icirc;ner une morbidit&eacute; importante, particuli&egrave;rement la perte d&#39;audition, acouph&egrave;ne, vertige et facial de paralysie. Les options de traitement actuelles pour VS incluent r&eacute;section microchirurgicale, radiochirurgie st&eacute;r&eacute;otaxique ou surveillance &eacute;troite surveillance, &agrave; chaque traitement option ex&eacute;cution associ&eacute; complications et morbidit&eacute;s. Plus important encore, aucune de ces options peut inverser d&eacute;finitivement perte d&#39;audition ou d&#39;acouph&egrave;nes. Identification d&#39;une nouvelle th&eacute;rapie m&eacute;dicale, par le biais de l&#39;inhibition mol&eacute;culaire cibl&eacute;e, est donc une strat&eacute;gie de traitement hautement souhaitable qui peut minimiser les complications d&eacute;coulant de la tumeur et le traitement, et plus important encore convenir aux patients dont les options sont limit&eacute;s en ce qui concerne chirurgicale ou perfectionner des interventions. Dans cette &eacute;tude, nous avons choisi d&#39;examiner l&#39;effet du Nilotinib sur VS. Nilotinib (Tasigna &reg;) est un inhibiteur de seconde g&eacute;n&eacute;ration de r&eacute;cepteurs tyrosine kinase (RTK) avec un profil cible semblable &agrave; celui de l&#39;imatinib (Gleevec &reg;), mais la puissance accrue, une diminution de la toxicit&eacute; et une plus grande p&eacute;n&eacute;tration cellulaire et tissulaire. Nilotinib vise non seulement l&#39;oncoprot&eacute;ine BCR-ABL, mais signalisation de r&eacute;cepteur de facteur de croissance &eacute;galement d&eacute;riv&eacute; des plaquettes (PDGF). Dans cette &eacute;tude pr&eacute;clinique, la lign&eacute;e humaine de cellules Schwannome de NF2 null que Hei-193 soumis &agrave; nilotinib inhibition d&eacute;montr&eacute;e diminue la viabilit&eacute;, la prolif&eacute;ration et la croissance d&#39;ancrage ind&eacute;pendant et a augment&eacute; l&#39;apoptose. Une dose quotidienne de nilotinib pendant 5 jours a inhib&eacute; la prolif&eacute;ration de HEI-I93 &agrave; une concentration ayant une pertinence clinique d&#39;une mani&egrave;re dose-d&eacute;pendante (IC (50) 3-5 &micro;mol/L) dans les cellules stimul&eacute;es par PDGF. Ces effets anti-tumorigenic du nilotinib &eacute;taient corr&eacute;l&eacute;s &agrave; l&#39;activation inhib&eacute;e de PDGFR-&alpha; et &beta;-PDGFR et principales voies de signalisation en aval. Ces exp&eacute;riences confirment un potentiel th&eacute;rapeutique pour Nilotinib dans VS.

Enqu&ecirc;te de l&#39;efficacit&eacute; th&eacute;rapeutique in vitro du nilotinib immortalis&eacute;es cellules humaines de schwannoma vestibulaire NF2 null.

Schwannoma vestibolare (VS) &egrave; un tumore al cervello comune fossa posteriore e anche se benigna pu&ograve; causare significative morbilit&agrave;, specialmente la perdita dell&#39;udito, tinnito, vertigini e facciale paralisi. Le attuali opzioni di trattamento per VS includono resezione microchirurgica, radiochirurgia stereotassica o stretta sorveglianza monitoraggio, opzione che trasportano associato con ogni trattamento complicazioni e morbidities. Soprattutto, nessuna di queste opzioni pu&ograve; invertire definitivamente la perdita dell&#39;udito o tinnito. Identificazione di una romanzo terapia medica, attraverso l&#39;uso di inibizione molecolare mirato, &egrave; quindi una strategia di trattamento altamente auspicabile che possa ridurre al minimo le complicazioni derivanti dal tumore e di trattamento e pi&ugrave; importante essere adatto per i pazienti le cui opzioni sono limitate rispetto alla chirurgica o radiochirurgico interventi. In questo studio abbiamo scelto di esaminare l&#39;effetto di Nilotinib sulla VS. Nilotinib (Tasigna &reg;) &egrave; un inibitore di seconda generazione del recettore tirosina chinasi (RTK) con un profilo di destinazione simile a quella di imatinib (Glivec &reg;), ma maggiore potenza, tossicit&agrave; diminuita e una maggiore penetrazione cellulare e dei tessuti. Nilotinib &egrave; destinato non solo l&#39;oncoproteina BCR-ABL del tipo, ma del ricevitore di fattore di crescita anche derivato dalle piastrine (PDGF) segnalazione. In questo studio preclinico, l&#39;umana NF2-null schwannoma cella linea che Hei-193 sottoposti ad inibizione di nilotinib ha dimostrato, diminuita vitalit&agrave;, proliferazione e crescita ancoraggio-indipendente e aumentata apoptosi. Una dose giornaliera di nilotinib per 5 giorni inibita proliferazione HEI-I93 ad una concentrazione clinicamente rilevante in modo dose-dipendente (IC(50) 3-5 &micro;mol/L) in cellule PDGF-stimolata. Questi effetti anti-tumorigenic di nilotinib erano correlati all&#39;attivazione inibito di PDGFR-&alpha; e PDGFR-&beta; e principali vie di segnalazione a valle. Questi esperimenti sostengono un potenziale terapeutico per Nilotinib nel VS.

Analisi dell&#39;efficacia terapeutica in vitro di nilotinib nelle cellule umane NF2-null di schwannoma vestibolare immortalate.

Medulloblastoma (MB) is the most common malignant brain tumor of childhood. Very little is known about aggressive forms of this disease, such as metastatic or recurrent MBs. In order to identify pathways involved in aggressive MB pathophysiology, we performed unbiased, whole genome microarrays on MB tumors at both the human and murine levels. Primary human MBs were compared, transcriptomically, to their patient-matched recurrent or metastatic tumors. Expression profiling was also performed on murine tumors from two spontaneously developing MB mouse models (Ptch+/- and Smo/Smo) that present with differing clinical severities. At both the human and murine levels we identified transforming growth factor-beta (TGF-Î²) as a potential contributor to MB progression/metastasis. Smad3, a major downstream component of the TGF-Î² pathway, was also evaluated using immunohistochemistry in malignant human tissues and was shown to correlate with MB metastasis and survival. Similarly, Smad3 expression during development identified a subset of cerebellar neuronal precursors as putative cells of origin for the Smad3-positive MBs. To our knowledge, this is the first study that links TGF-Î² to MB pathogenesis. Our research suggests that canonical activation of this pathway leads to better prognosis for patients.

Canonical TGF-Î² pathway activity is a predictor of SHH-driven medulloblastoma survival and delineates putative precursors in cerebellar development.

M&eacute;dulloblastome (Mo) est la tumeur maligne au cerveau plus courante de l&#39;enfance. On en sait tr&egrave;s peu sur des formes agressives de la maladie, tels que MBs m&eacute;tastatiques ou r&eacute;currents. Afin d&#39;identifier les voies impliqu&eacute;es dans agressif MB physiopathologie, nous avons effectu&eacute; puces g&eacute;nomique impartiale, tout sur MB tumeurs tant au niveau humain et murin. MBs humains primaires ont &eacute;t&eacute; compar&eacute;s, transcriptomically, de leurs patient assortie r&eacute;currents ou m&eacute;tastatiques des tumeurs. Profilage de l&#39;expression a &eacute;galement &eacute;t&eacute; effectu&eacute; sur les tumeurs murines de deux mod&egrave;les de souris de Mo spontan&eacute;ment en d&eacute;veloppement (Ptch +/-et Smo/Smo) qui pr&eacute;sentent diff&eacute;rentes s&eacute;v&eacute;rit&eacute;s cliniques. Tant au niveau humain et murin, nous avons identifi&eacute; le facteur de croissance transformant b&ecirc;ta (TGF-&beta;) comme un facteur potentiel de MB progression/m&eacute;tastase. Smad3, une composante importante en aval de la voie du TGF-&beta;, a &eacute;galement &eacute;t&eacute; &eacute;valu&eacute; par immunohistochimie dans les tissus humains malins et il a &eacute;t&eacute; d&eacute;montr&eacute; en corr&eacute;lation avec la survie et la m&eacute;tastase MB. De m&ecirc;me, Smad3 expression durant le d&eacute;veloppement identifi&eacute; un sous-ensemble des pr&eacute;curseurs neurones c&eacute;r&eacute;belleuses comme cellules pr&eacute;sum&eacute;es d&#39;origine pour les MBs Smad3-positif. &Agrave; notre connaissance, c&#39;est la premi&egrave;re &eacute;tude qui relie le TGF-&beta; &agrave; la pathogen&egrave;se de la MB. Nos recherches sugg&egrave;rent que l&#39;activation canonique de cette voie conduit &agrave; meilleur pronostic pour les patients.

Activit&eacute; de voie TGF-&beta; canonique est un facteur pr&eacute;dictif de survie d&#39;un m&eacute;dulloblastome pilot&eacute;e par SHH et d&eacute;limite des pr&eacute;curseurs putatifs en d&eacute;veloppement c&eacute;r&eacute;belleux.

Medulloblastoma (MB) &egrave; il pi&ugrave; comune tumore cerebrale maligno dell&#39;infanzia. Molto poco si sa sulle forme aggressive di questa malattia, come ricorrente o metastatico MBs. Al fine di individuare percorsi coinvolti nella fisiopatologia MB aggressivo, abbiamo eseguito imparziale, intero genoma microarrays su MB tumori sia a livello umano e murino. MBs umano primario sono stati confrontati, transcriptomically, ai loro tumori ricorrenti o metastatici paziente-matched. Delineamento di espressione &egrave; stata eseguita anche su tumori murini da due spontaneamente sviluppando MB modelli murini (Ptch + e Smo/Smo) che presentano diversi livelli di gravit&agrave; cliniche. Sia a livello umano e murino abbiamo identificato il fattore di crescita trasformante-beta (TGF-&beta;) come un potenziale collaboratore di progressione MB/metastasi. SMAD3, un importante componente a valle del percorso TGF-&beta;, inoltre &egrave; stata valutata mediante immunoistochimica nei tessuti umani maligni ed &egrave; stato mostrato per correlare con sopravvivenza e metastasi MB. Allo stesso modo, Smad3 espressione durante lo sviluppo ha identificato un sottoinsieme dei precursori neuronali cerebellari come putative cellule di origine per MBs Smad3-positivo. A nostra conoscenza, questo &egrave; il primo studio che collega TGF-&beta; a patogenesi MB. La nostra ricerca suggerisce che canonica attivazione di questo pathway porta ad una prognosi migliore per i pazienti.

Canonica attivit&agrave; di pathway di TGF-&beta; &egrave; un predittore di sopravvivenza medulloblastoma SHH-driven e delinea putativi precursori in sviluppo cerebellare.

Glioblastoma (GBM) is the most common primary brain tumor in adults. Despite current advances in therapy consisting of surgery followed by chemotherapy and radiation, the overall survival rate still remains poor. Therapeutic failures are partly attributable to the highly infiltrative nature of tumor adjacent to normal brain parenchyma. Recently, evidence is mounting to suggest that actin cytoskeleton dynamics are critical components of the cell invasion process. Drebrin is an actin-binding protein involved in the regulation of actin filament organization, and plays a significant role in cell motility; however, the role of drebrin in glioma cell invasiveness has not yet been fully elucidated. Therefore, this study was aimed to clarify the role of drebrin in glioma cell morphology and cell motility. Here we show that drebrin is expressed in glioma cell lines and in operative specimens of GBM. We demonstrate that stable overexpression of drebrin in U87 cells leads to alterations in cell morphology, and induces increased invasiveness in vitro while knockdown of drebrin in U87 cells by small interfering RNA (siRNA) decreases invasion and migration. In addition, we show that depletion of drebrin by siRNA alters glioma cell morphology in A172 GBM cell line. Our results suggest that drebrin contributes to the maintenance of cell shape, and may play an important role in glioma cell motility.

The role of drebrin in glioma migration and invasion.

Glioblastome (GBM) est la tumeur c&eacute;r&eacute;brale primaire plus courante chez les adultes. Malgr&eacute; les progr&egrave;s actuels en th&eacute;rapie consistant en chirurgie suivie de chimioth&eacute;rapie et la radioth&eacute;rapie, le taux de survie global reste encore pauvre. Les &eacute;checs th&eacute;rapeutiques sont en partie attribuables &agrave; la nature tr&egrave;s infiltrante de tumeur adjacente au parenchyme c&eacute;r&eacute;bral normal. R&eacute;cemment, la preuve est montage pour sugg&eacute;rer que l&#39;actine cytosquelette dynamique est des &eacute;l&eacute;ments essentiels du processus d&#39;invasion cellulaire. Drebrin est une prot&eacute;ine de liaison de l&#39;actine impliqu&eacute;e dans la r&eacute;gulation de l&#39;organisation de filaments actine et joue un r&ocirc;le important dans la motilit&eacute; cellulaire ; Cependant, le r&ocirc;le de drebrin dans l&#39;invasivit&eacute; de cellules de gliome n&#39;a pas encore &eacute;t&eacute; compl&egrave;tement &eacute;lucid&eacute;. Par cons&eacute;quent, cette &eacute;tude avait pour but de clarifier le r&ocirc;le de drebrin dans la motilit&eacute; cellulaire et de morphologie de cellulaire gliome. Nous montrons ici que drebrin est exprim&eacute;e dans les lign&eacute;es de cellules de gliome et sp&eacute;cimens du dispositif de GBM. Nous d&eacute;montrer cette surexpression stable de drebrin dans des chenaux de cellules U87 &agrave; des alt&eacute;rations dans la morphologie cellulaire et induit in vitro plu envahissant, tandis que la pr&eacute;cipitation de drebrin dans les cellules U87 par petits ARN interf&eacute;rents (siARN) diminue l&#39;invasion et la migration. En outre, nous montrons qu&#39;appauvrissement de la couche de drebrin de siARN modifie la morphologie cellulaire gliome dans la lign&eacute;e cellulaire A172 GBM. Nos r&eacute;sultats sugg&egrave;rent que drebrin contribue au maintien de la forme des cellules et peut jouer un r&ocirc;le important dans la motilit&eacute; cellulaire gliome.

Le r&ocirc;le de drebrin dans la migration de gliome et invasion.

Glioblastoma (GBM) &egrave; il pi&ugrave; comune tumore cerebrale primario negli adulti. Nonostante attuali progressi nella terapia consistente di chirurgia seguita da chemioterapia e radiazioni, il tasso di sopravvivenza globale rimane ancora povero. Fallimenti terapeutici sono in parte attribuibili alla natura altamente infiltrante del tumore adiacente al parenchima cerebrale normale. Recentemente, sono montaggio prove per suggerire che la dinamica del citoscheletro di actina &egrave; componenti critiche del processo di invasione cellulare. Drebrin &egrave; una proteina actina coinvolta nella regolazione della organizzazione di filamenti di actina e svolge un ruolo significativo nella motilit&agrave; cellulare; Tuttavia, il ruolo di drebrin nell&#39;invasivit&agrave; delle cellule di glioma non &egrave; ancora stata completamente chiarito. Pertanto, questo studio era finalizzato a chiarire il ruolo di drebrin nel glioma delle cellule delle cellule e morfologia motilit&agrave;. Qui vi mostriamo che drebrin &egrave; espressa in linee cellulari di glioma e negli esemplari operativi di GBM. Noi dimostrare quello stabile sovraespressione di drebrin in porta le cellule U87 ad alterazioni nella morfologia cellulare e induce maggiore invasivit&agrave; in vitro mentre atterramento di drebrin nelle cellule U87 da piccolo RNA interferente (siRNA) diminuisce l&#39;invasione e la migrazione. Inoltre, mostriamo che esaurimento delle drebrin di siRNA altera la morfologia cellulare glioma in linea cellulare A172 GBM. I nostri risultati suggeriscono che drebrin contribuisce al mantenimento della forma cellulare e pu&ograve; giocare un ruolo importante nella motilit&agrave; delle cellule di glioma.

Il ruolo di drebrin nel glioma migrazione e invasione.

Glioblastoma (GBM) is the most common and lethal primary brain tumor. Over the past few years tremendous genomic and proteomic characterization along with robust animal models of GBM have provided invaluable data that show that "GBM", although histologically indistinguishable from one another, are comprised of molecularly heterogenous diseases. In addition, robust pre-clinical models and a better understanding of the core pathways disrupted in GBM are providing a renewed optimism for novel strategies targeting these devastating tumors. Here, we summarize a brief history of the disease, our current molecular knowledge, lessons from animal models and emerging concepts of angiogenesis, invasion, and metabolism in GBM that may lend themselves to therapeutic targeting.

Glioblastoma, a brief review of history, molecular genetics, animal models and novel therapeutic strategies.

Glioblastome (GBM) est la tumeur c&eacute;r&eacute;brale primaire plus courantes et les plus mortelles. Au cours des derni&egrave;res quelques ann&eacute;es formidable g&eacute;nomique et prot&eacute;omiques caract&eacute;risation ainsi que les mod&egrave;les animaux robustes de GBM ont fourni des donn&eacute;es pr&eacute;cieuses qui montrent que &laquo; SOP &raquo;, bien qu&#39;histologiquement impossibles &agrave; distinguer de l&#39;autre, se composent de maladies mol&eacute;culairement h&eacute;t&eacute;rog&egrave;nes. En outre, des mod&egrave;les pr&eacute;cliniques robustes et mieux comprendre les voies de noyau perturb&eacute; dans GBM apportent un regain d&#39;optimisme pour les nouvelles strat&eacute;gies ciblant ces d&eacute;vastateurs des tumeurs. Nous r&eacute;sumons ici, une br&egrave;ve histoire de la maladie, notre actuelle connaissance mol&eacute;culaire, les le&ccedil;ons tir&eacute;es des mod&egrave;les animaux et les concepts &eacute;mergents de l&#39;angiogen&egrave;se, invasion et le m&eacute;tabolisme dans GBM qui ne se pr&ecirc;te pas au ciblage th&eacute;rapeutique.

Glioblastome, une br&egrave;ve revue d&#39;histoire, g&eacute;n&eacute;tique mol&eacute;culaire, mod&egrave;les animaux et de nouvelles strat&eacute;gies th&eacute;rapeutiques.

Glioblastoma (GBM) &egrave; il tumore cerebrale primario pi&ugrave; comuni e letali. Negli ultimi pochi anni tremenda genomiche e proteomiche caratterizzazione insieme robusti modelli animali di GBM hanno fornito preziosi dati che mostrano che &quot;GBM&quot;, sebbene istologicamente indistinguibili uno da altro, sono costituite da malattie molecolarmente eterogenee. Inoltre, robusti modelli preclinici e una migliore comprensione delle vie nucleo perturbato in GBM stanno fornendo un rinnovato ottimismo per romanzo strategie di targeting questi devastanti tumori. Riassumiamo qui, una breve storia della malattia, la nostra attuale conoscenza molecolare, lezioni da modelli animali e concetti emergenti dell&#39;angiogenesi, invasione e metabolismo in GBM che pu&ograve; si prestano a targeting terapeutico.

Glioblastoma, una breve rassegna della storia, genetica molecolare, modelli animali e nuove strategie terapeutiche.

The malignant glioma is the most common primary human brain tumor, and its migration and invasiveness away from the primary tumor mass are considered a leading cause of tumor recurrence and treatment failure. Recently, gene expression profiling revealed that the transmembrane glycoprotein CD99 is more highly expressed in malignant glioma than in normal brain. Although its function is not completely understood, CD99 is implicated in cell adhesion and migration in a variety of different cell types. CD99 has wild-type and splice variant isoforms. Previous studies have shown that wild-type CD99 may be an oncosuppressor in some tumors, distinct from the role of the splice variant isoform. In this study, our data reveal that only wild-type CD99 is expressed in human glioma cells and tissues. Using a tissue microarray, we validated that gliomas demonstrate higher expression of CD99 compared with nonneoplastic brain. To assess the role of CD99 in glioma migration and invasion, we inhibited CD99 expression by siRNA and demonstrated decreased glioma migration and invasion. In contrast, when CD99 was overexpressed in glioma cells, we observed enhancement of cell migration and invasiveness. An orthotopic brain tumor model demonstrates that CD99 overexpression significantly increases invasiveness and decreases survival rate. Interestingly, Rac activity was decreased and Rho activity was increased in CD99 overexpressing glioma cells, and the proportion of amoeboid cells to mesenchymal cells was significantly increased. Taken together, our findings suggest that CD99 may play an important role in the migration and invasion of human gliomas independent of Akt, ERK, or JNK signaling pathways. Moreover, CD99 might be involved in amoeboid-mesenchymal transition in glioma migration. CD99 may be an important future target to inhibit migration and invasion, especially in CD99-expressing gliomas.

Overexpression of CD99 Increases the Migration and Invasiveness of Human Malignant Glioma Cells.

Le gliome malin est la tumeur de cerveau humain primaire plus courante, la migration et son caract&egrave;re invasif de la tumeur primitive masse sont consid&eacute;r&eacute;s comme des principales causes d&#39;&eacute;chec de r&eacute;currence et traitement de tumeur. R&eacute;cemment, le profil d&#39;expression g&eacute;nique a r&eacute;v&eacute;l&eacute; que la glycoprot&eacute;ine transmembranaire CD99 plus fortement exprim&eacute;e dans les gliomes malins que dans le cerveau normal. Bien que sa fonction n&#39;est pas compl&egrave;tement &eacute;lucid&eacute;e, CD99 est impliqu&eacute;e dans l&#39;adh&eacute;sion cellulaire et migration dans une vari&eacute;t&eacute; de diff&eacute;rents types de cellules. CD99 a sauvage et &eacute;pisser les isoformes. Des &eacute;tudes ant&eacute;rieures ont montr&eacute; que CD99 sauvage peut &ecirc;tre un oncosuppressor dans certaines tumeurs, distingues le r&ocirc;le de l&#39;isoforme variant d&#39;&eacute;pissage. Dans cette &eacute;tude, nos donn&eacute;es r&eacute;v&egrave;lent que seulement sauvage CD99 est exprim&eacute;e dans les tissus et cellules de gliome humain. &Agrave; l&#39;aide d&#39;un tissu microarray, nous avons valid&eacute; que les gliomes d&eacute;montrent une expression plus &eacute;lev&eacute;e de CD99 compar&eacute;e &agrave; cerveau non n&eacute;oplasiques. Pour &eacute;valuer le r&ocirc;le de CD99 dans migration de gliome et invasion, nous inhib&eacute;e CD99 expression de siARN et a d&eacute;montr&eacute; une diminution de gliome migration et invasion. En revanche, lorsque CD99 &eacute;tait surexprim&eacute; dans les cellules de gliome, nous avons observ&eacute; la mise en valeur de la migration cellulaire et son caract&egrave;re invasif. Un mod&egrave;le orthotopique de tumeur c&eacute;r&eacute;brale montre que CD99 surexpression significative augmente le pouvoir envahissant et diminue le taux de survie. Fait int&eacute;ressant, a diminu&eacute; l&#39;activit&eacute; Rac Rho activit&eacute; a augment&eacute; dans les cellules de gliome sur-exprimant CD99 et la proportion des cellules amibo&iuml;des aux cellules m&eacute;senchymateuses augmente significativement. Ensemble, nos r&eacute;sultats sugg&egrave;rent que CD99 peut jouer un r&ocirc;le important dans la migration et l&#39;invasion des gliomes humains ind&eacute;pendants de Akt, ERK ou JNK, voies de signalisation. En outre, CD99 interviendrait en transition amibo&iuml;de-m&eacute;senchymateuse en migration de gliome. CD99 peut &ecirc;tre une cible importante de future d&#39;inhiber la migration et l&#39;invasion, en particulier dans les gliomes CD99 exprimant.

La surexpression de CD99 augmente la Migration et le pouvoir invasif des cellules de gliome malin humain.

Il glioma maligno &egrave; il pi&ugrave; comune tumore del cervello umano primario e la migrazione e l&#39;invasivit&agrave; lontano dal tumore primario massa sono considerati delle principali cause del fallimento di ricorrenza e il trattamento di tumore. Di recente, analisi di espressione genica ha rivelato che la glicoproteina transmembrana CD99 pi&ugrave; altamente &egrave; espresso nel glioma maligno che nel cervello normale. Anche se la sua funzione completamente non &egrave; capita, CD99 &egrave; implicato nell&#39;adesione cellulare e la migrazione in una variet&agrave; di diversi tipi di cellule. CD99 ha wild-type e splice variante isoforme. Studi precedenti hanno mostrato che il selvaggio-tipo CD99 pu&ograve; essere un oncosoppressori in alcuni tumori, distinti dal ruolo dell&#39;isoforma variante di splice. In questo studio, i nostri dati rivelano che solo il selvaggio-tipo CD99 &egrave; espresso in tessuti e cellule di glioma umano. Usando un microarray di tessuti, abbiamo convalidato che gliomi dimostrano la pi&ugrave; alta espressione di CD99 rispetto al cervello cicatrizziale. Per valutare il ruolo di CD99 nel glioma migrazione e invasione, abbiamo inibito CD99 espressione di siRNA e dimostrato glioma diminuita migrazione e invasione. Al contrario, quando CD99 era overexpressed in cellule di glioma, abbiamo osservato aumento della migrazione cellulare e invasivit&agrave;. Un modello di tumore cerebrale ortotopico dimostra che CD99 sovraespressione notevolmente aumenta l&#39;invasivit&agrave; e diminuisce il tasso di sopravvivenza. &Egrave; interessante notare che, Rac attivit&agrave; era diminuita attivit&agrave; Rho &egrave; stato aumentato in cellule di glioma all CD99 ed &egrave; stata aumentata significativamente la percentuale delle cellule ameboidi di cellule mesenchimali. Presi insieme, i nostri risultati suggeriscono che CD99 pu&ograve; giocare un ruolo importante nella migrazione e invasione di gliomi umani indipendentemente del Akt, ERK, JNK vie di segnalazione. Inoltre, CD99 potrebbero essere coinvolti nella transizione ameboidi mesenchimali in migrazione di glioma. CD99 pu&ograve; essere un importante obiettivo futuro per inibire la migrazione e l&#39;invasione, soprattutto nei gliomi esprimendo CD99.

Sovraespressione di CD99 aumenta la migrazione e l&#39;invasivit&agrave; delle cellule umane di Glioma maligno.

Metabolic adaptation is essential for cell survival during nutrient deprivation. We report that eukaryotic elongation factor 2 kinase (eEF2K), which is activated by AMP-kinase (AMPK), confers cell survival under acute nutrient depletion by blocking translation elongation. Tumor cells exploit this pathway to adapt to nutrient deprivation by reactivating the AMPK-eEF2K axis. Adaptation of transformed cells to nutrient withdrawal is severely compromised in cells lacking eEF2K. Moreover, eEF2K knockdown restored sensitivity to acute nutrient deprivation in highly resistant human tumor cell lines. InÂ vivo, overexpression of eEF2K rendered murine tumors remarkably resistant to caloric restriction. Expression of eEF2K strongly correlated with overall survival in human medulloblastoma and glioblastoma multiforme. Finally, C.Â elegans strains deficient in efk-1, the eEF2K ortholog, were severely compromised in their response to nutrient depletion. Our data highlight a conserved role for eEF2K in protecting cells from nutrient deprivation and in conferring tumor cell adaptation to metabolic stress. PAPERCLIP:

The eEF2 Kinase Confers Resistance to Nutrient Deprivation by Blocking Translation Elongation.

Adaptation m&eacute;tabolique est essentielle pour la survie des cellules au cours de la privation en nutriments. Les auteurs rapportent que kinase de facteur 2 &eacute;longation eucaryote (eEF2K), qui est activ&eacute;e par l&#39;AMP-kinase (AMPK), conf&egrave;re la survie des cellules en vertu de l&#39;&eacute;puisement des nutriments aigu&euml; en bloquant l&#39;&eacute;longation de la traduction. Cellules tumorales exploitent cette voie pour s&#39;adapter &agrave; la privation nutritive en r&eacute;activant l&#39;axe de l&#39;AMPK-eEF2K. Adaptation des cellules transform&eacute;es au retrait des &eacute;l&eacute;ments nutritifs est gravement compromise dans les cellules sans eEF2K. En outre, eEF2K knockdown restaur&eacute; sensibilit&eacute; aigu&euml; privation nutritive dans les lign&eacute;es cellulaires tumorales humaines tr&egrave;s r&eacute;sistant. In vivo, la surexpression d&#39;eEF2K rendu des tumeurs murines remarquablement r&eacute;sistants &agrave; la restriction calorique. Expression d&#39;eEF2K est fortement corr&eacute;l&eacute; avec la survie globale dans multiforme de m&eacute;dulloblastome et glioblastome humain. Enfin, les souches de c. elegans d&eacute;ficientes en efk-1, l&#39;orthologue de l&#39;eEF2K, ont &eacute;t&eacute; gravement compromises dans leur r&eacute;ponse &agrave; l&#39;&eacute;puisement des nutriments. Nos r&eacute;sultats mettent en &eacute;vidence un r&ocirc;le conserv&eacute; pour eEF2K dans la protection des cellules de privation en nutriments et en conf&eacute;rant l&#39;adaptation de cellules de tumeur au stress m&eacute;tabolique. TROMBONE :

Sameer Agnihotri

Brain Tumor Research Centre

Hospital for Sick Children, Toronto Medical Discovery Tower

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

Sameer Agnihotri

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Brain Tumor Research Centre

Hospital for Sick Children, Toronto Medical Discovery Tower

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

Brain Tumor Research Centre