Dataset Information

Mitochondrial DNA mutations in Medulloblastoma.

ABSTRACT: To date, several studies on genomic events underlying medulloblastoma (MB) biology have expanded our understanding of this tumour entity and led to its division into four groups-WNT, SHH, group 3 (G3) and group 4 (G4). However, there is little information about the relevance of pathogenic mitochondrial DNA (mtDNA) mutations and their consequences across these. In this report, we describe the case of a female patient with MB and a mitochondriopathy, followed by a study of mtDNA variants in MB groups. After being diagnosed with G4 MB, the index patient was treated in line with the HIT 2000 protocol with no indications of relapse after five years. Long-term side effects of treatment were complemented by additional neurological symptoms and elevated lactate levels ten years later, resulting in suspected mitochondrial disease. This was confirmed by identifying a mutation in the MT-TS1 gene which appeared homoplasmic in patient tissue and heteroplasmic in the patient's mother. Motivated by this case, we explored mtDNA mutations across 444 patients from ICGC and HIT cohorts. While there was no statistically significant enrichment of mutations in one MB group, both cohorts encompassed a small group of patients harbouring potentially deleterious mtDNA variants. The case presented here highlights the possible similarities between sequelae caused by MB treatment and neurological symptoms of mitochondrial dysfunction, which may apply to patients across all MB groups. In the context of the current advances in characterising and interpreting mtDNA aberrations, recognising affected patients could enhance our future knowledge regarding the mutations' impact on carcinogenesis and cancer treatment.

SUBMITTER: Funke VLE

PROVIDER: S-EPMC10373251 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Mitochondrial DNA mutations in Medulloblastoma.

Funke Viktoria L E VLE Sandmann Sarah S Melcher Viktoria V Seggewiss Jochen J Horvath Judit J Jäger Natalie N Kool Marcel M Jones David T W DTW Pfister Stefan M SM Milde Till T Rutkowski Stefan S Mynarek Martin M Varghese Julian J Sträter Ronald R Rust Stephan S Seelhöfer Anja A Reunert Janine J Fiedler Barbara B Schüller Ulrich U Marquardt Thorsten T Kerl Kornelius K

Acta neuropathologica communications 20230727 1

To date, several studies on genomic events underlying medulloblastoma (MB) biology have expanded our understanding of this tumour entity and led to its division into four groups-WNT, SHH, group 3 (G3) and group 4 (G4). However, there is little information about the relevance of pathogenic mitochondrial DNA (mtDNA) mutations and their consequences across these. In this report, we describe the case of a female patient with MB and a mitochondriopathy, followed by a study of mtDNA variants in MB gro ...[more]

PMID: 37501103

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Dataset Information

Mitochondrial DNA mutations in Medulloblastoma.

Publications

Mitochondrial DNA mutations in Medulloblastoma.

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