MB_450k_methylation
Ontology highlight
ABSTRACT:
PROVIDER: EGAD00010002370 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Genomic rearrangements typically occur progressively during tumor development. Recent findings, however, suggest an alternative mechanism, involving chromosome shattering and reshuffling ('chromothripsis'), for which no genetic basis has yet been described. Whole-genome sequencing of a Sonic-Hedgehog medulloblastoma (SHH-MB) brain tumor from a patient with a germline TP53 mutation (Li-Fraumeni syndrome) revealed massive, complex rearrangements resulting from chromothripsis. Integrating TP53 status with genomic rearrangement data in additional medulloblastomas revealed a striking association between TP53 mutation and chromothripsis in SHH-MBs. Unexpectedly, five seemingly sporadic SHH-MB patients with chromothripsis harbored TP53 germline mutations – findings relevant for clinical management. Analysis of additional tumor entities substantiated a link between TP53 mutation and chromothripsis, beyond general genomic instability. Among these, we observed a strong association between somatic TP53 mutations and chromothripsis in acute myeloid leukemia. These findings implicate p53 in the initiation of, or cellular reaction to, chromothripsis – a novel role for the 'guardian of the genome'. The DNA copy-number profiles of 11 primary medulloblastoma samples were analyzed on the Affymetrix Mapping250K Nsp array, together with data from 70 primary samples taken from GSE21140. Data from diploid reference samples were taken from GSE9222. Additionally, DNA copy-number profiles for 19 additional medulloblastoma samples were generated on the Affymetrix SNP6 platform with matched blood samples.
2012-01-20 | E-GEOD-34258 | biostudies-arrayexpress
Project description:Genomic rearrangements typically occur progressively during tumor development. Recent findings, however, suggest an alternative mechanism, involving chromosome shattering and reshuffling ('chromothripsis'), for which no genetic basis has yet been described. Whole-genome sequencing of a Sonic-Hedgehog medulloblastoma (SHH-MB) brain tumor from a patient with a germline TP53 mutation (Li-Fraumeni syndrome) revealed massive, complex rearrangements resulting from chromothripsis. Integrating TP53 status with genomic rearrangement data in additional medulloblastomas revealed a striking association between TP53 mutation and chromothripsis in SHH-MBs. Unexpectedly, five seemingly sporadic SHH-MB patients with chromothripsis harbored TP53 germline mutations – findings relevant for clinical management. Analysis of additional tumor entities substantiated a link between TP53 mutation and chromothripsis, beyond general genomic instability. Among these, we observed a strong association between somatic TP53 mutations and chromothripsis in acute myeloid leukemia. These findings implicate p53 in the initiation of, or cellular reaction to, chromothripsis – a novel role for the 'guardian of the genome'.
2012-01-20 | GSE34258 | GEO
Project description:Quiescent Sox2+ cells drive hierarchical growth and relapse in Sonic hedgehog subgroup medulloblastoma
| EGAD00001000818 | EGA
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
Project description:We report the application for high-throughput profiling of transcriptome, chromatin-associated proteins and histone-modifications on a genome-wide level in iPSC-derived family control astrocytes vs LFS (Li-Fraumeni Syndrome) patient astrocytes.
2023-02-18 | GSE163088 | GEO
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 (MB) is the most prevalent pediatric cerebral cancer, but is rare in adults. The vast majority of MB arises sporadically but some few cases occur in association with germline alterations in genes such as PTCH1, SUFU, APC, and TP53. Additional genes are responsible for MB predisposition including some that have probably not been described so far either due to the rarity of the cases and/or to the low penetrance. Here we report the case of a 27 years old woman affected by Pitt Hopkins syndrome due to a heterozygous germline pathogenic variant in TCF4 who has developed a Sonic Hedgehog (SHH)-driven MB. Somatic loss of function variants of TCF4 have been identified in SHH MB especially among adults and this case raises the question of a predisposition to late-onset SHH MB associated with TCF4 germline alteration.
2019-02-14 | GSE126545 | GEO
Project description:Whole Exome sequencing of two patients with Cardiac angiosarcoma in Li-Fraumeni-like families discovers that a mutation in the pot1 gene is responsible for cardiac angiosarcoma in tp53-negative li-fraumeni-like families
2015-09-14 | E-MTAB-3858 | biostudies-arrayexpress