Pediatric medulloblastoma (MB) is the most common solid malignant brain neoplasm, with Group 3 (G3) MB representing the most aggressive subgroup. MYC amplification is an independent poor prognostic factor in G3 MB, however, therapeutic targeting of the MYC pathway remains limited and alternative therapies for G3 MB are urgently needed. Here we show that the RNA-binding protein, Musashi-1 (MSI1) is an essential mediator of G3 MB in both MYC-overexpressing mouse models and patient-derived xenografts. MSI1 inhibition abrogates tumor initiation and significantly prolongs survival in both models. We identify binding targets of MSI1 in normal neural and G3 MB stem cells and then cross referenced these data with unbiased large-scale screens at the transcriptomic, translatomic and proteomic levels to systematically dissect its functional role. Comparative integrative multi-omic analyses of these large datasets reveal cancer-selective MSI1-bound targets sharing multiple MYC associated pathways, providing a valuable resource for context-specific therapeutic targeting of G3 MB.

• MeSH
• lidé MeSH
• meduloblastom * genetika   MeSH
• myši MeSH
• nádory mozečku * genetika   MeSH
• nádory mozku * MeSH
• proteiny nervové tkáně MeSH
• proteiny vázající RNA genetika   MeSH
• proteomika MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• MSI1 protein, human MeSH Prohlížeč
• proteiny nervové tkáně MeSH
• proteiny vázající RNA MeSH

While molecular subgrouping has revolutionized medulloblastoma classification, the extent of heterogeneity within subgroups is unknown. Similarity network fusion (SNF) applied to genome-wide DNA methylation and gene expression data across 763 primary samples identifies very homogeneous clusters of patients, supporting the presence of medulloblastoma subtypes. After integration of somatic copy-number alterations, and clinical features specific to each cluster, we identify 12 different subtypes of medulloblastoma. Integrative analysis using SNF further delineates group 3 from group 4 medulloblastoma, which is not as readily apparent through analyses of individual data types. Two clear subtypes of infants with Sonic Hedgehog medulloblastoma with disparate outcomes and biology are identified. Medulloblastoma subtypes identified through integrative clustering have important implications for stratification of future clinical trials.

• Klíčová slova
• copy number, gene expression, integrative clustering, medulloblastoma, methylation, subgroups,
• MeSH
• genomika MeSH
• individualizovaná medicína * MeSH
• kohortové studie MeSH
• lidé MeSH
• meduloblastom klasifikace   genetika   terapie   MeSH
• metylace DNA MeSH
• shluková analýza MeSH
• stanovení celkové genové exprese MeSH
• variabilita počtu kopií segmentů DNA MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon-driven, functional genomic mouse model of medulloblastoma with 'humanized' in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (<5%). Whole-genome sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (<12% diagnostic events were retained at recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy.

• MeSH
• buněčné klony účinky léků   metabolismus   patologie   MeSH
• cílená molekulární terapie metody   MeSH
• Drosophila melanogaster cytologie   genetika   MeSH
• genom lidský genetika   MeSH
• kraniospinální iradiace MeSH
• lidé MeSH
• lokální recidiva nádoru genetika   patologie   terapie   MeSH
• meduloblastom genetika   patologie   radioterapie   chirurgie   terapie   MeSH
• modely nemocí na zvířatech MeSH
• mutační analýza DNA MeSH
• myši MeSH
• nádory mozečku genetika   patologie   radioterapie   chirurgie   terapie   MeSH
• radioterapie řízená obrazem MeSH
• selekce (genetika) účinky léků   MeSH
• signální transdukce MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Medulloblastoma is a highly malignant paediatric brain tumour currently treated with a combination of surgery, radiation and chemotherapy, posing a considerable burden of toxicity to the developing child. Genomics has illuminated the extensive intertumoral heterogeneity of medulloblastoma, identifying four distinct molecular subgroups. Group 3 and group 4 subgroup medulloblastomas account for most paediatric cases; yet, oncogenic drivers for these subtypes remain largely unidentified. Here we describe a series of prevalent, highly disparate genomic structural variants, restricted to groups 3 and 4, resulting in specific and mutually exclusive activation of the growth factor independent 1 family proto-oncogenes, GFI1 and GFI1B. Somatic structural variants juxtapose GFI1 or GFI1B coding sequences proximal to active enhancer elements, including super-enhancers, instigating oncogenic activity. Our results, supported by evidence from mouse models, identify GFI1 and GFI1B as prominent medulloblastoma oncogenes and implicate 'enhancer hijacking' as an efficient mechanism driving oncogene activation in a childhood cancer.

• MeSH
• dítě MeSH
• DNA vazebné proteiny genetika   metabolismus   MeSH
• lidé MeSH
• lidské chromozomy, pár 9 genetika   MeSH
• meduloblastom klasifikace   genetika   patologie   MeSH
• myši MeSH
• onkogeny genetika   MeSH
• protoonkogenní proteiny genetika   metabolismus   MeSH
• represorové proteiny genetika   metabolismus   MeSH
• strukturální variace genomu genetika   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• zesilovače transkripce genetika   MeSH
• zvířata MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• DNA vazebné proteiny MeSH
• GFI1 protein, human MeSH Prohlížeč
• GFI1B protein, human MeSH Prohlížeč
• protoonkogenní proteiny MeSH
• represorové proteiny MeSH
• transkripční faktory MeSH

PURPOSE: Medulloblastoma comprises four distinct molecular subgroups: WNT, SHH, Group 3, and Group 4. Current medulloblastoma protocols stratify patients based on clinical features: patient age, metastatic stage, extent of resection, and histologic variant. Stark prognostic and genetic differences among the four subgroups suggest that subgroup-specific molecular biomarkers could improve patient prognostication. PATIENTS AND METHODS: Molecular biomarkers were identified from a discovery set of 673 medulloblastomas from 43 cities around the world. Combined risk stratification models were designed based on clinical and cytogenetic biomarkers identified by multivariable Cox proportional hazards analyses. Identified biomarkers were tested using fluorescent in situ hybridization (FISH) on a nonoverlapping medulloblastoma tissue microarray (n = 453), with subsequent validation of the risk stratification models. RESULTS: Subgroup information improves the predictive accuracy of a multivariable survival model compared with clinical biomarkers alone. Most previously published cytogenetic biomarkers are only prognostic within a single medulloblastoma subgroup. Profiling six FISH biomarkers (GLI2, MYC, chromosome 11 [chr11], chr14, 17p, and 17q) on formalin-fixed paraffin-embedded tissues, we can reliably and reproducibly identify very low-risk and very high-risk patients within SHH, Group 3, and Group 4 medulloblastomas. CONCLUSION: Combining subgroup and cytogenetic biomarkers with established clinical biomarkers substantially improves patient prognostication, even in the context of heterogeneous clinical therapies. The prognostic significance of most molecular biomarkers is restricted to a specific subgroup. We have identified a small panel of cytogenetic biomarkers that reliably identifies very high-risk and very low-risk groups of patients, making it an excellent tool for selecting patients for therapy intensification and therapy de-escalation in future clinical trials.

• MeSH
• čipová analýza tkání MeSH
• cytogenetika MeSH
• dítě MeSH
• hodnocení rizik MeSH
• hybridizace in situ fluorescenční MeSH
• jaderné proteiny genetika   MeSH
• kojenec MeSH
• lidé MeSH
• lidské chromozomy, pár 11 MeSH
• lidské chromozomy, pár 14 MeSH
• meduloblastom genetika   mortalita   patologie   terapie   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádorové biomarkery genetika   MeSH
• prediktivní hodnota testů MeSH
• předškolní dítě MeSH
• prognóza MeSH
• proporcionální rizikové modely MeSH
• protein Gli2 s motivem zinkových prstů MeSH
• proteiny hedgehog * genetika   MeSH
• proteiny Wnt * genetika   MeSH
• protoonkogenní proteiny c-myc genetika   MeSH
• regulace genové exprese u nádorů MeSH
• reprodukovatelnost výsledků MeSH
• rizikové faktory MeSH
• stanovení celkové genové exprese MeSH
• transkripční faktory Krüppel-like genetika   MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• GLI2 protein, human MeSH Prohlížeč
• jaderné proteiny MeSH
• MYC protein, human MeSH Prohlížeč
• nádorové biomarkery MeSH
• protein Gli2 s motivem zinkových prstů MeSH
• proteiny hedgehog * MeSH
• proteiny Wnt * MeSH
• protoonkogenní proteiny c-myc MeSH
• SHH protein, human MeSH Prohlížeč
• transkripční faktory Krüppel-like MeSH