Modulating autophagy as a therapeutic strategy for the treatment of paediatric high-grade glioma.
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ABSTRACT:
SUBMITTER: Howarth A
PROVIDER: S-EPMC8028648 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Overall paediatric high grade glioma (pHGG) has a poor prognosis, in part due to the lack of understanding of the underlying biology. We therefore used high resolution 244k oligo array comparative genomic hybridisation (oligo aCGH) (Agilent Technologies) to analyse DNA from 38 formalin-fixed paraffin embedded pHGG samples, including 13 DIPG (ten pre-treatment samples and three post-mortem). The pattern of gains and losses were distinct from those seen in HGG arising in adults. In particular we found 1q gain in 22% of our cohort compared to 9% in adults. Homozygous loss at 8p12 was seen in 6/38 (15%) of pHGG. This deletion has not been previously reported in adult or paediatric high grade gliomas. The minimal deleted region is of the gene ADAM3A and homozygous deletion of ADAM3A was confirmed by quantitative real time PCR (qPCR). This novel homozygous deletion of ADAM3A in pHGG merits further study. Loss of CDKN2A/CDKN2B was seen in 4/38 (10%) samples by oligo a CGH, confirmed by FISH on TMAs and was restricted to supratentorial tumours. Amplification of the 4q11-13 region was detected in 8% of cases and included PDGFRA and KIT, subsequent qPCR analysis was consistent with amplification of PDGFRA. MYCN amplification was seen in 2/38 samples (5%) and was shown to be significantly associated with anaplastic astrocytomas (p=0.03). Overall DIPG shared similar spectrum of changes to supratentorial HGG with some notable differences including high frequency of 17p loss and 14q loss and lack of CDKN2A/CDKN2B deletion. To our knowledge, this study examines the largest DIPG cohort to date using high-throughput genetic techniques.
2010-12-01 | GSE21420 | GEO
Project description:Overall paediatric high grade glioma (pHGG) has a poor prognosis, in part due to the lack of understanding of the underlying biology. We therefore used high resolution 244k oligo array comparative genomic hybridisation (oligo aCGH) (Agilent Technologies) to analyse DNA from 38 formalin-fixed paraffin embedded pHGG samples, including 13 DIPG (ten pre-treatment samples and three post-mortem). The pattern of gains and losses were distinct from those seen in HGG arising in adults. In particular we found 1q gain in 22% of our cohort compared to 9% in adults. Homozygous loss at 8p12 was seen in 6/38 (15%) of pHGG. This deletion has not been previously reported in adult or paediatric high grade gliomas. The minimal deleted region is of the gene ADAM3A and homozygous deletion of ADAM3A was confirmed by quantitative real time PCR (qPCR). This novel homozygous deletion of ADAM3A in pHGG merits further study. Loss of CDKN2A/CDKN2B was seen in 4/38 (10%) samples by oligo a CGH, confirmed by FISH on TMAs and was restricted to supratentorial tumours. Amplification of the 4q11-13 region was detected in 8% of cases and included PDGFRA and KIT, subsequent qPCR analysis was consistent with amplification of PDGFRA. MYCN amplification was seen in 2/38 samples (5%) and was shown to be significantly associated with anaplastic astrocytomas (p=0.03). Overall DIPG shared similar spectrum of changes to supratentorial HGG with some notable differences including high frequency of 17p loss and 14q loss and lack of CDKN2A/CDKN2B deletion. To our knowledge, this study examines the largest DIPG cohort to date using high-throughput genetic techniques. 38 high grade glioma samples including 13 DIPG (ten pre-treatment samples and three post-mortem) analysed by Agilent 244K array CGH. Samples BSG 1, 2, 3, 5, 6, 7, 8, 9, 10 and 11 are the ten pre-treatment DIPG samples. Samples BSG 4, 12 and 13 are the three post-treatment DIPG samples.
2010-12-01 | E-GEOD-21420 | biostudies-arrayexpress
Project description:Paediatric high-grade gliomas (pHGG) are aggressive central nervous system tumours with a poor prognosis. BRAFV600E mutant pHGGs can be treated with targeted BRAF inhibitors, which have shown both preclinical activity and potent clinical efficacy. Unfortunately, the development of drug resistance results in disease relapse or progression and is the primary cause of treatment failure. While there is a lot of data to explain mechanisms of resistance in other BRAFV600E tumours, comparatively little is known about the mechanisms of BRAF inhibitor resistance in BRAFV600E pHGG. Recent literature has identified aberrations in members of the RAS/RAF/ERK pathway, the PI3K/AKT/MTOR pathway and the cell cycle as major contributors to the resistance profile. A range of novel therapies have been suggested to overcome BRAF inhibitor drug resistance in BRAFV600E pHGG. This review will discuss the current literature available for BRAF inhibitor resistant BRAFV600E pHGGs and provide an overview of the currently available and proposed therapies.
| S-EPMC9792688 | biostudies-literature
Project description:Brain tumours are the leading cause of paediatric cancer-associated death worldwide. High-grade glioma (HGG) represents a main cause of paediatric brain tumours and is associated with poor prognosis despite surgical and chemoradiotherapeutic advances. The molecular genetics of paediatric HGG (pHGG) are distinct from those in adults, and therefore, adult clinical trial data cannot be extrapolated to children. Compared to adult HGG, pHGG is characterised by more frequent mutations in PDGFRA, TP53 and recurrent K27M and G34R/V mutations on histone H3. Ongoing trials are investigating novel targeted therapies in pHGG. Promising results have been achieved with BRAF/MEK and PI3K/mTOR inhibitors. Combination of PI3K/mTOR, EGFR, CDK4/6, and HDAC inhibitors are potentially viable options. Inhibitors targeting the UPS proteosome, ADAM10/17, IDO, and XPO1 are more novel and are being investigated in early-phase trials. Despite preclinical and clinical trials holding promise for the discovery of effective pHGG treatments, several issues persist. Inadequate blood-brain barrier penetration, unfavourable pharmacokinetics, dose-limiting toxicities, long-term adverse effects in the developing child, and short-lived duration of response due to relapse and resistance highlight the need for further improvement. Future pHGG management will largely depend on selecting combination therapies which work synergistically based on a sound knowledge of the underlying molecular target pathways. A systematic investigation of multimodal therapy with chemoradiotherapy, surgery, target agents and immunotherapy is paramount. This review provides a comprehensive overview of pHGG focusing on molecular genetics and novel targeted therapies. The diagnostics, genetic discrepancies with adults and their clinical implications, as well as conventional treatment approaches are discussed.
| S-EPMC9247880 | biostudies-literature
Project description:This report describes a single-centre study with temozolomide (TMZ) (200 mg m(-2) day(-1) x 5 per cycle of 28 days) in children with (recurrent) high-grade glioma. Magnetic resonance imaging was performed every two cycles. In all, 20 patients were treated between 1998 and 2001 after the UKCCSG/SFOP TMZ phase II trial. All patients had measurable disease. Totally, 15 patients had a relapse after surgery+/-radiotherapy+/-chemotherapy. Overall, five patients received TMZ after surgery or biopsy, awaiting radiotherapy. There were one clinically malignant grade II glioma, 11 grade III and eight grade IV gliomas. Seven tumours had oligodendroglial features. Mean age at start of TMZ was 12.0 years (range 3-20.5 years). In total, eight patients had >8 cycles (range 3-30). One VGPR (currently in CR after surgery), three PRs (with a PFS of 4, 4 and 11 months, respectively) and one MR (PFS 14 months) were observed. Three out of five responses occurred after >4 courses. The overall response rate was 20%. Median progression-free survival (PFS) was 2.0 months (range 3 weeks-34+ months). PFS rate was 20% after 6 months. Median overall survival (OS) was 10 months. Nine patients showed a clinical improvement. Three patients vomitted shortly after TMZ administration, eight patients (13 cycles) experienced grade III/IV thrombocytopenia, occurring predominantly during the fourth week of the first two cycles. Five patients experienced neutropenia, and three patients febrile neutropenia. TMZ is a well-tolerated ambulatory treatment for children with malignant glial tumours. This drug warrants further study in these highly chemoresistant tumours and should be studied either as upfront therapy or in combination therapy.
| S-EPMC2409857 | biostudies-other
Project description:Brain tumours are the most common cause of death among children with solid tumours, and high-grade gliomas (HGG) are among the most devastating forms with very poor outcomes. In the search for more effective treatments for paediatric HGG, there is a need for better experimental models. To date, there are no xenograft zebrafish models developed for human paediatric HGG; existing models rely on adult cells. The use of paediatric models is of great importance since it is well known that the genetic and epigenetic mechanisms behind adult and paediatric disease differ greatly. In this study, we present a clinically relevant in vivo model based on paediatric primary glioma stem cell (GSC) cultures, which after orthotopic injection into the zebrafish larvae, can be monitored using confocal imaging over time. We show that cells invade the brain tissue and can be followed up to 8 days post-injection while they establish in the fore/mid brain. This model offers an in vivo system where tumour invasion can be monitored and drug treatments quickly be evaluated. The possibility to monitor patient-specific cells has the potential to contribute to a better understanding of cellular behaviour and personalised treatments in the future.
| S-EPMC9139401 | biostudies-literature
Project description:High-grade glioma is highly invasive and malignant, resistant to combined therapies, and easy to relapse. A better understanding of circular RNA (circRNA) biological function in high-grade glioma might contribute to the therapeutic efficacy. Here, a circRNA merely upregulated in high-grade glioma, circGLIS3 (hsa_circ_0002874, originating from exon 2 of GLIS3), was validated by microarray and Real-time quantitative reverse transcription PCR (qRT-PCR). The role of circGLIS3 in glioma was assessed by functional experiments both in vitro and in vivo. Fluorescence in situ hybridization (FISH), RNA pull-down, RNA immunoprecipitation (RIP), and immunohistochemical staining were performed for mechanistic study. Cocultured brain endothelial cells with glioma explored the role of exosome-derived circGLIS3 in the glioma microenvironment. We found that upregulation of circGLIS3 promoted glioma cell migration and invasion and showed aggressive characteristics in tumor-bearing mice. Mechanistically, we found that circGLIS3 could promote the Ezrin T567 phosphorylation level. Moreover, circGLIS3 could be excreted by glioma through exosomes and induced endothelial cell angiogenesis. Our findings indicate that circGLIS3 is upregulated in high-grade glioma and contributes to the invasion and angiogenesis of glioma via modulating Ezrin T567 phosphorylation.
| S-EPMC8446459 | biostudies-literature
Project description:PurposeThe maintenance of telomere length prevents cancer cell senescence and occurs via two mutually exclusive mechanisms: (a) reactivation of telomerase expression and (b) activation of alternative lengthening of telomeres (ALT). ALT is frequently related to alterations on ATRX, a chromatin-remodelling protein. Recent data have identified different molecular subgroups of paediatric high-grade glioma (pHGG) with mutations of H3F3A, TERTp and ATRX; however, differences in telomere length among these molecular subgroups were not thoroughly examined.MethodsWe investigated which genetic alterations trigger the ALT mechanism in 52 IDH-wildtype, 1p/19q-wildtype pHGG. Samples were analysed for telomere length using Tel-FISH. ATRX nuclear loss of expression was assessed by IHC, H3F3A and TERTp mutations by DNA sequencing, and TERTp methylation by MS-PCR.ResultsMutant H3.3 was found in 21 cases (40.3%): 19.2% with K27M mutation and 21.1% with G34R mutation. All H3.3G34R-mutated cases showed the ALT phenotype (100%); on the opposite, only 40% of the H3.3K27M-mutated showed ALT activation. ATRX nuclear loss was seen in 16 cases (30.7%), associated sometimes with the G34R mutation, and never with the K27M mutation. ATRX nuclear loss was always related to telomere elongation. TERTp C250T mutations were rare (5.4%) and were not associated with high intensity Tel-FISH signals, as TERTp hyper-methylation detected in 21% of the cases. H3.3/ATRX/TERTp-wildtype pHGG revealed all basal levels of telomere length.ConclusionOur results show a strong association between H3.3 mutations and ALT, and highlight the different telomeric profiles in histone-defined subgroups: H3.3-G34R mutants always trigger ALT to maintain telomere length, irrespective of ATRX status, whereas only some H3.3-K27M tumours activate ALT. These findings suggest that acquiring the gly34 mutation on H3.3 might suffice to trigger the ALT mechanism.
| S-EPMC7875853 | biostudies-literature
Project description:High-grade glioma is highly aggressive and malignant, resistant to combined therapies and easy to relapse. A better understanding of circRNA biological function in high-grade glioma might contribute to the therapeutic efficacy. Here, a circRNA merely up-regulated in high-grade glioma, circGLIS3 (hsa_circ_0002874, originating from exon 2 of GLIS3), was validated by microarray and qRT-PCR. Functional experiments uncovered that up-regulation of circGLIS3 promoted glioma cell migration and invasion, and showed aggressive characteristics in tumor-bearing mice. Fluorescence in situ hybridization, RNA pull-down, RNA immunoprecipitation and immunohistochemical staining showed that circGLIS3 could promoted Ezrin T567 phosphorylation. Further investigation showed that circGLIS3 could be excreted by glioma through exosomes and induced endothelial cells angiogenesis. This study indicates that circGLIS3 is up-regulated in high-grade glioma and contributes to the invasion and angiogenesis of glioma via promoting Ezrin T567 phosphorylation.
2021-09-22 | GSE165859 | GEO
Project description:Pediatric high-grade gliomas (HGGs)--including glioblastoma multiforme, anaplastic astrocytoma, and diffuse intrinsic pontine glioma--are difficult to treat and are associated with an extremely poor prognosis. There are no effective chemotherapeutic regimens for the treatment of pediatric HGG, but many new treatment options are in active investigation. There are crucial molecular differences between adult and pediatric HGG such that results from adult clinical trials cannot simply be extrapolated to children. Molecular markers overexpressed in pediatric HGG include PDGFR? and P53. Amplification of EGFR is observed, but to a lesser degree than in adult HGG. Potential molecular targets and new therapies in development for pediatric HGG are described in this review. Research into bevacizumab in pediatric HGG indicates that its activity is less than that observed in adult HGG. Similarly, tipifarnib was found to have minimal activity in pediatric HGG, whereas gefitinib has shown greater effects. After promising phase I findings in children with primary CNS tumors, the integrin inhibitor cilengitide is being investigated in a phase II trial in pediatric HGG. Studies are also ongoing in pediatric HGG with 2 EGFR inhibitors: cetuximab and nimotuzumab. Other novel treatment modalities under investigation include dendritic cell-based vaccinations, boron neutron capture therapy, and telomerase inhibition. While the results of these trials are keenly awaited, the current belief is that multimodal therapy holds the greatest promise. Research efforts should be directed toward building multitherapeutic regimens that are well tolerated and that offer the greatest antitumor activity in the setting of pediatric HGG.
| S-EPMC3177659 | biostudies-other