Genetic Alterations in Oligodendroglial Tumors

Oligodendroglial tumours are defined by characteristic molecular signatures that underpin their diagnosis, prognosis and therapeutic response. The sentinel hallmark is the co-deletion of chromosomal arms 1p and 19q, which arises from an unbalanced translocation and correlates with chemosensitivity and prolonged survival. Nearly all such codeleted tumours harbour mutations in isocitrate dehydrogenase (IDH1 or IDH2), yielding the oncometabolite 2-hydroxyglutarate and driving widespread epigenetic reprogramming. Beyond these core events, secondary alterations include inactivation of tumour suppressors CIC (on 19q) and FUBP1 (on 1p), promoter hypermethylation of MGMT, mutations in the TERT promoter and alterations in chromatin remodellers such as ATRX. Integrated transcriptomic, genomic and methylomic studies have revealed further heterogeneity within codeleted cases, distinguishing subgroups with oligodendrocyte-precursor-like or neuronal lineage expression and varying degrees of MYC pathway activation. In tumours lacking 1p/19q codeletion, alternative pathways involving TP53 mutations, ATRX loss and astrocytic differentiation predominate, conferring a less favourable prognosis. Advances in high-throughput profiling and machine learning have refined molecular classification, enabling more precise stratification and paving the way for tailored therapeutic strategies.

Research from Nature Portfolio

Multi-layered analyses have delineated three distinct subgroups within 1p/19q-codeleted oligodendroglial tumours, each associated with a specific cell-lineage signature—mature oligodendrocytes, oligodendrocyte precursor cells and neurons. This classification aligns with differences in clinical aggressiveness, revealing that precursor-like tumours exhibit enhanced MYC pathway activation through varied mechanisms including MYC genomic gain, MAX loss, promoter hypomethylation and microRNA down-regulation. These insights refine prognostic models independently of histological grade and offer novel entry points for targeted intervention.

Genetic Alterations in Oligodendroglial Tumors publication trend

The graph below shows the total number of articles in genetic alterations in oligodendroglial tumors across all publications each year (not limited to Nature Index journals).

Technical terms

1p/19q codeletion: Combined loss of the short arm of chromosome 1 and the long arm of chromosome 19, defining a molecularly distinct subgroup of oligodendroglial tumours with favourable prognosis.

Isocitrate dehydrogenase (IDH) mutation: Somatic alteration in IDH1 or IDH2 genes leading to aberrant oncometabolite production and serving as a key marker for glioma classification.

Next-generation sequencing (NGS): High-throughput DNA sequencing technology enabling comprehensive detection of mutations, copy-number changes and structural variants in tumour genomes.

Liquid biopsy: Minimally invasive method analysing circulating tumour DNA or other biomarkers in blood or bodily fluids for real-time tumour monitoring.

Multi-omics: Integrated analysis of genomic, transcriptomic and epigenomic datasets to achieve refined molecular subtyping and uncover oncogenic pathways.

References

1. Efficient diagnosis of IDH-mutant gliomas: 1p/19qNET assesses 1p/19q codeletion status using weakly-supervised learning. npj Precision Oncology (2023).
2. Integrated multi-omics analysis of oligodendroglial tumours identifies three subgroups of 1p/19q co-deleted gliomas. Nature Communications (2016).
3. Oligodendroglioma: pathology, molecular mechanisms and markers. Acta Neuropathologica (2015).
4. Comprehensive clinical assays for molecular diagnostics of gliomas: the current state and future prospects. Frontiers in Molecular Biosciences (2023).
5. Design and Validation of a Gene-Targeted, Next-Generation Sequencing Panel for Routine Diagnosis in Gliomas. Cancers (2019).