MAGIC_Sox2 - samples
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ABSTRACT:
PROVIDER: EGAD00001000818 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Sonic Hedgehog subgroup medulloblastomas
| PRJNA384622 | ENA
Project description:Medulloblastoma, the most common malignant pediatric brain tumor, is highly heterogeneous with distinct molecular subtypes and cellular origins. Although current treatments improve survival rates, patients suffer severe treatment-related side effects and often relapse of tumors carrying resistance mutations, underscoring an urgent need for alternative targeted therapies. Currently, the genetic alterations underlying this disease are not fully understood. Here we identify GNAS, encoding the G-protein Gs-alpha, as a potent tumor suppressor gene in medulloblastoma. GNAS specifically defines a subset of aggressive Sonic Hedgehog (Shh)-group medulloblastomas. Gnas loss-of-function in distinct lineage progenitors of the developing hindbrain suffices to initiate medulloblastoma. We find that Gs-alpha is highly enriched at primary cilia of granule neuron precursors and suppresses Shh signaling not only by regulating classic cAMP-dependent pathway but also controlling ciliary trafficking of Smoothened. Concurrent cAMP elevation and Smoothened inhibition robustly arrests tumor cell growth in Gnas mutants. We further reveal oligodendrocyte progenitors as a novel cellular origin for anatomically-distinct Shh-associated medulloblastomas. Together, we identify a previously unrecognized tumor suppressor function of Gs-alpha in medulloblastoma partially mediated through inhibiting Shh signaling, and uncover Gs-alpha as a molecular link across disparate cells of origin among Shh-group medulloblastomas, pointing to G- protein modulation as a potential therapeutic avenue. Transgenic medulloblastoma mouse models were analyzed by Affymetrix Mouse Gene 1.1 ST Array in order to determine their molecular subgroup. Tumors extracted from hGFAP:GnasCKO and Oligo1:GnasCKO transgenic mice were analyzed in 8 replicates each, together with normal mouse cerebellum.
2014-08-24 | E-GEOD-60417 | biostudies-arrayexpress
Project description:450k methylation arrays of primary and relapse tumor of a single case of sonic hedgehog medulloblastoma with Li-Fraumeni syndrome
| EGAD00010002370 | EGA
Project description:We undertook a comprehensive clinical and biological investigation of serial medulloblastoma biopsies obtained at diagnosis and relapse. Combined MYC gene family amplifications and P53 pathway defects commonly emerged at relapse, and all patients in this molecular group died of rapidly progressive disease post-relapse. To study this genetic interaction, we investigated a transgenic model of MYCN-driven medulloblastoma and found spontaneous development of Trp53 inactivating mutations. Abrogation of Trp53 function in this model produced aggressive tumors that mimicked the characteristics of relapsed human tumors with combined P53-MYC dysfunction. Restoration of p53 activity, genetic and therapeutic suppression of MYCN all reduced tumor growth and prolonged survival. Our findings identify P53–MYC interactions which emerge at medulloblastoma relapse as biomarkers of clinically aggressive disease that may be targeted therapeutically. Using this dataset, assignation of medulloblastoma molecular subgroup by Illumina 450k microarray was performed for diagnostic and relapsed medulloblastoma samples to compare subgroup membership at diagnosis and relapse. We investigated the DNA methylation profiles of 18 diagnostic and 22 relapsing samples (including 15 diagnostic / relapse pairs) using the Illumina 450k methylation microarray
2015-04-23 | E-GEOD-62618 | biostudies-arrayexpress
Project description:Medulloblastoma is the most common malignant brain tumor in children. Here we describe a medulloblastoma model using iPS cell-derived human neuroepithelial stem (NES) cells generated from a Gorlin syndrome patient carrying a germline mutation in the Sonic hedgehog (SHH) receptor PTCH1. We found that Gorlin NES cells formed tumors in mouse cerebellum mimicking human medulloblastoma. Re-transplantation of tumor-isolated NES (tNES) cells resulted in accelerated tumor formation, cells with reduced growth factor dependency, enhanced neurosphere formation in vitro, and increased sensitivity to Vismodegib. Using our model we identified LGALS1 to be a GLI target gene that is upregulated in both Gorlin tNES cells and SHH-subgroup of medulloblastoma patients. Taken together, we demonstrate that NES cells derived from Gorlin patients can be used as a resource to model medulloblastoma initiation and progression, and to identify novel putative targets.
2020-07-16 | GSE106718 | GEO
Project description:Background: Medulloblastoma (MB) is one of the most common malignant pediatric brain tumors. Metastasis and relapse are the leading causes of death in MB patients. The initiation of the SHH subgroup of MB (SHH-MB) is due to the aberrant activation of Sonic Hedgehog (Shh) signaling. However, the mechanisms for its metastasis are still unknown. Results: AMP-dependent protein kinase (AMPK) restrains the activation of Shh signaling pathway, thereby impeding the proliferation of SHH-MB cells. More importantly, AMPK also hinders the growth and metastasis of SHH-MB cells by regulating NF-kB signaling pathway. Furthermore, Vismodegib and TPCA-1, which block the Shh and NF-kB pathways, respectively, synergistically restrained the growth, migration, and invasion of SHH-MB cells. Conclusions: This work demonstrates that AMPK functions through two signaling pathways, SHH-GLI1 and NF-kB. AMPK-NF-kB axis is a potential target for molecular therapy of SHH-MB, and the combinational blockade of NF-kB and Shh pathways confers synergy for SHH-MB therapy.
2023-07-01 | GSE218076 | GEO
Project description:Inhibition of Medulloblastoma growth by a sonic hedgehog (SHH) inhibitor
| PRJNA309314 | ENA
Project description:Several basic helix-loop-helix (bHLH) transcription factors are upregulated in Sonic Hedgehog subgroup of medulloblastoma (SHH MB). Olig2, a neural bHLH transcription factor known to regulate differentiation of neural cell populations, is broadly expressed in mouse models of SHH MB. ChIP-Seq of Olig2 revealed its binding to a large number of sites near genes known to promote SHH MB tumorigenesis, suggesting a potential role for Olig2 in regulating transcriptional programme of MB.
2024-03-23 | GSE103824 | GEO
Project description:The morphogen and mitogen, Sonic Hedgehog, activates a Gli1-dependent transcription program that drives proliferation of granule neuron progenitors (GNPs) within the external germinal layer of the postnatally developing cerebellum. Medulloblastomas with mutations activating the Sonic Hedgehog signaling pathway preferentially arise within the external germinal layer, and the tumor cells closely resemble GNPs. Atoh1/Math1, a basic helix-loop-helix transcription factor essential for GNP histogenesis, does not induce medulloblastomas when expressed in primary mouse GNPs that are explanted from the early postnatal cerebellum and transplanted back into the brains of naïve mice. However, enforced expression of Atoh1 in primary GNPs enhances the oncogenicity of cells overexpressing Gli1 by almost three orders of magnitude. Unlike Gli1, Atoh1 cannot support GNP proliferation in the absence of Sonic Hedgehog signaling and does not govern expression of canonical cell cycle genes. Instead, Atoh1 maintains GNPs in a Sonic Hedgehog-responsive state by regulating genes that trigger neuronal differentiation, including many expressed in response to bone morphogenic protein-4. Therefore, by targeting multiple genes regulating the differentiation state of GNPs, Atoh1 collaborates with the pro-proliferative Gli1-dependent transcriptional program to influence medulloblastoma development. Keywords: disease state analysis 14 samples, 1 time series, 2 engineered Medulloblastoma tumors
2010-07-08 | E-GEOD-19684 | biostudies-arrayexpress