Extrachromosomal DNA Dynamics in Cancer Biology

Extrachromosomal DNA (ecDNA) has emerged as a fundamental driver of tumour evolution, heterogeneity and therapy resistance. These circular, acentric DNA elements frequently harbour oncogenes, enhancers and regulatory sequences that escape chromosomal controls, enabling rapid copy-number gains and elevated transcription of cancer-promoting genes. The dynamic behaviour of ecDNA encompasses de novo formation from chromosomal breakpoints, structural diversification through circular recombination and unequal segregation during cell division. This plasticity fuels intratumoral heterogeneity, accelerates clonal selection and underpins adaptive responses to targeted therapies. Recent advances in sequencing and imaging have illuminated how ecDNA forms early in tumourigenesis, reshapes gene regulatory landscapes and interacts with nuclear architecture. A deeper understanding of ecDNA dynamics offers new avenues for prognostic biomarkers and for therapeutic strategies aimed at destabilising or eliminating these potent oncogenic drivers.

Research from Nature Portfolio

Recent studies have revealed that ecDNA can arise in pre-malignant lesions, with analyses of patients under surveillance for Barrett’s oesophagus showing that ecDNA appears before overt carcinoma and progressively accumulates oncogenes and immune-related genes. This early manifestation highlights ecDNA as both a marker and mechanism of neoplastic transition. Complementary single-cell parallel sequencing methods have exposed intercellular differences in ecDNA content, showing that oncogene-bearing ecDNAs are clonally maintained yet structurally varied within tumours, while smaller circles follow distinct selection patterns. These approaches demonstrate that circular recombination events continually reshape ecDNA structure and modulate gene expression at the single-cell level. In parallel, computational reconstruction of focal amplifications from whole-genome data has corroborated a model in which focal oncogene amplifications commonly derive from ecDNA formation. Detailed amplicon architectures, including human-viral hybrid circles, have been resolved, confirming that ecDNA underlies many recurrent high-level copy-number changes in cancer genomes.

Extrachromosomal DNA Dynamics in Cancer Biology publication trend

The graph below shows the total number of articles in extrachromosomal dna dynamics in cancer biology across all publications each year (not limited to Nature Index journals).

Technical terms

Extrachromosomal DNA (ecDNA): Large, circular DNA molecules separate from chromosomes that frequently carry oncogenes and drive tumour heterogeneity.

microDNA: Small circular DNAs (<400 bp) derived from gene-rich genomic regions, capable of generating regulatory small RNAs.

Focal amplification: Localised high-copy-number gain of genomic segments, often mediated by ecDNA.

Circular recombination: DNA rearrangement processes within ecDNA that generate structural diversity and modulate copy number.

Single-cell sequencing: Techniques that profile DNA and RNA from individual cells to reveal heterogeneity in ecDNA content and transcriptional impact.

References

1. Extrachromosomal DNA in the cancerous transformation of Barrett’s oesophagus. Nature (2023).
2. Parallel sequencing of extrachromosomal circular DNAs and transcriptomes in single cancer cells. Nature Genetics (2023).
3. Exploring the landscape of focal amplifications in cancer using AmpliconArchitect. Nature Communications (2019).
4. Production of Extrachromosomal MicroDNAs Is Linked to Mismatch Repair Pathways and Transcriptional Activity. Cell Reports (2015).
5. Small extrachromosomal circular DNAs, microDNA, produce short regulatory RNAs that suppress gene expression independent of canonical promoters. Nucleic Acids Research (2019).