scholarly journals MODL-20. A BIOBANK OF ~100 PATIENT-DERIVED MODELS REPRESENTING BIOLOGICAL HETEROGENEITY AND DISTINCT THERAPEUTIC DEPENDENCIES IN PAEDIATRIC HIGH GRADE GLIOMA AND DIPG

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii414-iii415
Author(s):  
Diana Carvalho ◽  
Alan Mackay ◽  
Sara Temelso ◽  
Elisa Izquierdo ◽  
Elisabet Potente Fernandez ◽  
...  

Abstract Paediatric high-grade glioma comprise multiple biological and clinical subgroups, the majority of which urgently require novel therapies. Patient-derived models represent useful tools for mechanistic and preclinical investigations based upon their retention of key genetic/epigenetic features and their amenability to high-throughput approaches. We have collected ~100 in vitro models representing multiple subtypes (H3.3/H3.2/H3.1K27M, H3.3G34R/V, BRAF, MYCN_amp, NTRK_fusion, hypermutator, others) established under 2D (laminin) and/or 3D (neurosphere) conditions, credentialed by phenotypic (growth, invasion/migration) and molecular (methylation array, DNA sequencing, RNAseq) comparison to the original tumour sample. These were derived from patients at our local hospitals (n=29), as part of national co-clinical trials (n=19), from international collaborating centres (n=11), or shared directly by research groups worldwide (n=45). These have variously been subjected to pharmacological (approved/experimental drug libraries) and/or genetic screening (whole-genome CRISPR) to identify specific biological dependencies. Many have been established as orthotopic xenografts in vivo (PDX), with detailed pathological and radiological correlations with the clinical disease, and with tumorigenic latencies ranging from 48–435 days. This resource has allowed us to identify genotype-specific synthetic lethalities and responses to targeted inhibitors, including olaparib (PARP) with ATRX, nutlin-3 (MDM2) with PPM1D, AZD1775 (WEE1) with TP53, and CYC065 (CDK9) with MYCN-amplification. Combinatorial screening highlighted synergies in ACVR1-mutant DIPG between novel ALK2 inhibitors and ONC201 (DRD2). Rapid screening allows for feedback of drug sensitivities to treating clinicians at relapse, whilst mechanistic underpinning of these interactions and use of the models to identify specific mediators of resistance will allow for rational future trial design.

2021 ◽  
Vol 22 (6) ◽  
pp. 2962
Author(s):  
Louise Orcheston-Findlay ◽  
Samuel Bax ◽  
Robert Utama ◽  
Martin Engel ◽  
Dinisha Govender ◽  
...  

The life expectancy of patients with high-grade glioma (HGG) has not improved in decades. One of the crucial tools to enable future improvement is advanced models that faithfully recapitulate the tumour microenvironment; they can be used for high-throughput screening that in future may enable accurate personalised drug screens. Currently, advanced models are crucial for identifying and understanding potential new targets, assessing new chemotherapeutic compounds or other treatment modalities. Recently, various methodologies have come into use that have allowed the validation of complex models—namely, spheroids, tumouroids, hydrogel-embedded cultures (matrix-supported) and advanced bioengineered cultures assembled with bioprinting and microfluidics. This review is designed to present the state of advanced models of HGG, whilst focusing as much as is possible on the paediatric form of the disease. The reality remains, however, that paediatric HGG (pHGG) models are years behind those of adult HGG. Our goal is to bring this to light in the hope that pGBM models can be improved upon.


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 3505-3505
Author(s):  
Olivier Rixe ◽  
John Charles Morris ◽  
Robert Wesolowski ◽  
Emrullah Yilmaz ◽  
Richard Curry ◽  
...  

3505 Background: BXQ-350 is a first-in-class agent comprised of Saposin C (SapC) and dioleoyl phosphatidylserine (DOPS). SapC, a multifunctional lysosomal-activator glycoprotein that preferentially interacts with tumor cell phospholipids, has demonstrated anti-tumor effects in both in vitro and in vivo preclinical models. The tolerability and preliminary efficacy of BXQ-350 in the first-in-human study are summarized here. Methods: Eighty-six refractory solid tumor (ST) or high-grade glioma (HGG) patients age ≥18 (36F:50M, age 24-81) were enrolled in a 3-part first-in-human trial (NCT02859857) from 2016-2019 and received at least one dose of BXQ-350. Doses were administered via intravenous infusion during 28-day cycles until disease progression occurred. The previously reported part 1 dose escalation portion of the study (9 HGG, 9 ST patients) established the highest planned dose of 2.4mg/kg as safe but did not identify a maximum tolerated dose. The part 2 expansion cohort treated 37 patients (18 HGG and 19 ST) and an additional part 3 cohort treated 31 ST gastrointestinal (GI) patients, both at the 2.4 mg/kg dose level. Preliminary antitumor activity was evaluated (RECISTv1.1 or RANO). Results: There were no BXQ-350-related serious adverse events, dose limiting toxicities or withdrawals with the exception of 1 allergic type reaction. Three patients (Glioblastoma, Ependymoma, Appendiceal) demonstrated a partial response per RECIST/RANO. Two HGG patients with progressive radiologic enhancement were seen to have treatment effect at surgery, and hence considered to have stable disease. Seven patients (2 HGG, 3 GI, 2 other ST) remain on study and have received treatment for 9+ to 41+ months, with 5 patients treated for > 1 year. A continuing treatment protocol is planned in order to allow these patients to remain on BXQ-350 treatment. Conclusions: BXQ-350 was well tolerated with no significant dose-limiting toxicities at the highest planed dose level. Preliminary results indicate this novel agent demonstrated possible anti-tumor activity in refractory solid tumors and HGG. Clinical trial information: NCT03967093) .


Oncotarget ◽  
2016 ◽  
Vol 7 (17) ◽  
pp. 23416-23424 ◽  
Author(s):  
Yi-Hsien Chen ◽  
Patrick J. Cimino ◽  
Jingqin Luo ◽  
Sonika Dahiya ◽  
David H. Gutmann
Keyword(s):  

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3589
Author(s):  
Sanne Venneker ◽  
Alwine B. Kruisselbrink ◽  
Zuzanna Baranski ◽  
Ieva Palubeckaite ◽  
Inge H. Briaire-de Bruijn ◽  
...  

Mutations in the isocitrate dehydrogenase (IDH1 or IDH2) genes are common in enchondromas and chondrosarcomas, and lead to elevated levels of the oncometabolite D-2-hydroxyglutarate causing widespread changes in the epigenetic landscape of these tumors. With the use of a DNA methylation array, we explored whether the methylome is altered upon progression from IDH mutant enchondroma towards high-grade chondrosarcoma. High-grade tumors show an overall increase in the number of highly methylated genes, indicating that remodeling of the methylome is associated with tumor progression. Therefore, an epigenetics compound screen was performed in five chondrosarcoma cell lines to therapeutically explore these underlying epigenetic vulnerabilities. Chondrosarcomas demonstrated high sensitivity to histone deacetylase (HDAC) inhibition in both 2D and 3D in vitro models, independent of the IDH mutation status or the chondrosarcoma subtype. siRNA knockdown and RNA expression data showed that chondrosarcomas rely on the expression of multiple HDACs, especially class I subtypes. Furthermore, class I HDAC inhibition sensitized chondrosarcoma to glutaminolysis and Bcl-2 family member inhibitors, suggesting that HDACs define the metabolic state and apoptotic threshold in chondrosarcoma. Taken together, HDAC inhibition may represent a promising targeted therapeutic strategy for chondrosarcoma patients, either as monotherapy or as part of combination treatment regimens.


2022 ◽  
Author(s):  
Zhiyuan Sun ◽  
Yufu Zhu ◽  
Xia Feng ◽  
Xiaoyun Liu ◽  
Kunlin Zhou ◽  
...  

Abstract H3.3K27M is a newly identified molecular pathology marker in glioma and is especially correlated with the malignancy of diffuse intrinsic pontine glioma (DIPG). In recent years, accumulating research has revealed that other types of glioma also contain the H3.3K27M mutation. However, the role of H3.3K27M in high-grade adult glioma, which is the most malignant glioma, has not been investigated. In this study, we focused on exploring the expression and function of H3.3K27M in high-grade adult glioma patients. We found that H3.3K27M is partly highly expressed in high-grade glioma tissues. Then, we introduced H3.3K27M into H3.3 wild-type glioma cells, U87 cells and LN229 cells. We found that H3.3K27M did not regulate the growth of glioma in vitro and in vivo; however, the survival of mice with transplanted tumors was significantly reduced. Further investigation revealed that H3.3K27M expression mainly promoted the migration and invasion of glioma cells. Moreover, we certified that H3.3K27M overexpression enhanced the protein levels of ꞵ-catenin and p-ꞵ-catenin, the protein and mRNA levels of ubiquitin-specific protease 1 (USP1), and the protein level of enhancer of zeste homolog 2 (EZH2). Importantly, the ꞵ-catenin inhibitor XAV-939 significantly attenuated the upregulation of the aforementioned proteins. Overall, the H3.3K27M mutation is present in a certain proportion of high-grade glioma patients and facilitates a poor prognosis by promoting the metastasis of glioma by regulating the ꞵ-catenin/USP1/EZH2 pathway.


2020 ◽  
Author(s):  
Diana M Carvalho ◽  
Sara Temelso ◽  
Alan Mackay ◽  
Helen N Pemberton ◽  
Rebecca Rogers ◽  
...  

ABSTRACTPaediatric high grade glioma and diffuse midline glioma (including DIPG) are comprised of multiple biological and clinical subgroups, the majority of which urgently require novel therapies. Patient-derived in vitro primary cell cultures represent potentially useful tools for mechanistic and preclinical investigation based upon their retention of key features of tumour subgroups under experimental conditions amenable to high-throughput approaches. We present 17 novel primary cultures derived from patients in London, Dublin and Belfast, and together with cultures established or shared from Barcelona, Brisbane, Rome and Stanford, assembled a panel of 52 models under 2D (laminin matrix) and/or 3D (neurospheres) conditions, fully credentialed by phenotypic and molecular comparison to the original tumour sample (methylation BeadArray, panel/exome sequencing, RNAseq). In screening a subset of these against a panel of ~400 approved chemotherapeutics and small molecules, we identified specific dependencies associated with tumour subgroups and/or specific molecular markers. These included MYCN-amplified cells and ATM/DNA-PK inhibitors, and DIPGs with PPM1D activating truncating mutations and inhibitors of MDM2 or PARP1. Specific mutations in PDGFRA were found to confer sensitivity to a range of RTK inhibitors, though not all such mutations conferred sensitivity to targeted agents. Notably, dual PDGFRA/FGFR and downstream pathway MEK inhibitors showed profound effects against both PDGFRA-sensitising mutant and FGFR1-dependent non-brainstem pHGG and DIPG. In total, 85% cells were found to have at least one drug screening hit in short term assays linked to the underlying biology of the patient’s tumour, providing a rational approach for individualised clinical translation.


2020 ◽  
Author(s):  
Cristiana Barone ◽  
Mariachiara Buccarelli ◽  
Francesco Alessandrini ◽  
Miriam Pagin ◽  
Laura Rigoldi ◽  
...  

AbstractCancer stem cells (CSC) are essential for tumorigenesis. The transcription factor Sox2 is overexpressed in brain tumors. In gliomas, Sox2 is essential to maintain CSC. In mouse high-grade glioma pHGG, Sox2 deletion causes cell proliferation arrest and inability to reform tumors in vivo; 134 genes are significantly derepressed. To identify genes mediating the effects of Sox2 deletion, we overexpressed into pHGG cells nine among the most derepressed genes, and identified four genes, Cdkn2b, Ebf1, Zfp423 and Hey2, that strongly reduced cell proliferation in vitro and brain tumorigenesis in vivo. CRISPR/Cas9 mutagenesis, or pharmacological inactivation, of each of these genes, individually, showed that their activity is essential for the proliferation arrest caused by Sox2 deletion. These Sox2-inhibited antioncogenes also inhibited clonogenicity in primary human glioblastoma-derived cancer stem-like cell lines. These experiments identify critical anti-oncogenic factors whose inhibition by Sox2 is involved in CSC maintenance, defining new potential therapeutic targets for gliomas.Table of Contents ImageMain PointsSox2 maintains glioma tumorigenicity by repressing the antioncogenic activity of a regulatory network involving the Ebf1, Hey2, Cdkn2b and Zfp423 genes.Mutation of these genes prevents the cell proliferation arrest of Sox2-deleted glioma cells.


2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i19-i20
Author(s):  
Kasey Skinner ◽  
Tomoyuki Koga ◽  
Shunichiro Miki ◽  
Robert F Gruener ◽  
R Stephanie Huang ◽  
...  

Abstract Diffuse intrinsic pontine glioma (DIPG) is a subset of high-grade glioma that occurs predominantly in children and has no cure. Up to 80% of DIPG harbor a heterozygous point mutation that results in a lysine 27 to methionine substitution in histone variant H3.3 (H3.3K27M). Existing DIPG models have provided insight into the role of H3.3K27M but have limitations: genetically engineered murine models often rely on overexpression of the mutant histone to form tumors; patient-derived xenografts (PDX) are more genetically faithful but preclude examination of the effect of individual mutations on pathogenesis. To address these shortcomings and better recapitulate the genetics of human tumors, we designed a novel DIPG model based on human induced pluripotent stem cells (iPSC) edited via CRISPR to express heterozygous H3.3K27M. Edited iPSC were chemically differentiated into neural progenitor cells, which upon implantation into the brainstems of immunodeficient mice formed diffusely invasive tumors that were histologically consistent with high-grade glioma. Further, neurospheres cultured from primary tumors formed secondary tumors upon reimplantation with more diffuse invasion, suggesting in vivo evolution. To validate this model’s relevance to DIPG transcriptionally, we performed RNA-sequencing on a cohort of primary and secondary tumor neurospheres (termed primary and secondary iDIPG) and compared them to published RNA-seq data from pediatric PDX and patient tumor samples. Hierarchical clustering and principal component analysis on differentially expressed genes (P<0.05) showed that H3.3K27M iDIPG cluster with H3.3K27M PDX and patient tumors. Further, ssGSEA showed that H3.3K27M iDIPG are enriched for astrocytic and mesenchymal signature genes, a defining feature of H3.3K27M DIPG. Finally, we found that primary H3.3K27M iDIPG neurospheres are sensitive to panobinostat, an HDAC inhibitor shown to be effective against H3.3K27M DIPG cells in vitro. Overall, these data suggest that H3.3K27M iDIPG are a promising tool for investigating DIPG biology and new therapeutic strategies.


2020 ◽  
Author(s):  
Chen He ◽  
Ke Xu ◽  
Xiaoyan Zhu ◽  
Paige S. Dunphy ◽  
Brian Gudenas ◽  
...  

AbstractPediatric high-grade glioma (pHGG) is a major contributor to cancer-related death in children. In vitro and in vivo disease models reflecting the intimate connection between developmental context and pathogenesis of pHGG are essential to advance understanding and identify therapeutic vulnerabilities. We established 21 patient-derived pHGG orthotopic xenograft (PDOX) models and eight matched cell lines from diverse groups of pHGG. These models recapitulated histopathology, DNA methylation signatures, mutations and gene expression patterns of the patient tumors from which they were derived, and included rare subgroups not well-represented by existing models. We deployed 16 new and existing cell lines for high-throughput screening (HTS). In vitro HTS results predicted variable in vivo response to inhibitors of PI3K/mTOR and MEK signaling pathways. These unique new models and an online interactive data portal to enable exploration of associated detailed molecular characterization and HTS chemical sensitivity data provide a rich resource for pediatric brain tumor research.


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