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Updated: Oct 16, 2025
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Genome-wide Purification of Extrachromosomal Circular DNA from Eukaryotic Cells
Published on: April 4, 2016
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Gene Amplification and the Extrachromosomal Circular DNA
1Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8521, Hiroshima, Japan.
Genes
|October 23, 2021
Summary
Extrachromosomal circles drive oncogene amplification in cancer by initiating gene amplification, leading to double minutes (DMs) or homogeneously staining regions (HSR). Understanding these circles aids cancer treatment and biopharmaceutical production.
Area of Science:
- Molecular Biology
- Cancer Genetics
- Genomics
Background:
- Oncogene amplification is a key driver in human cancers.
- Amplified genes are found in extrachromosomal DNA (double minutes/DMs) or chromosomal regions (HSR).
Purpose of the Study:
- To review and discuss the nature, behavior, generation, and role of extrachromosomal circles in cancer genome plasticity.
- To highlight the significance of these circles in cancer understanding and therapeutic development.
Main Methods:
- Literature review of recent articles on extrachromosomal circles and gene amplification.
- Synthesis of information on the mechanisms and consequences of extrachromosomal circle formation.
Main Results:
- Extrachromosomal circles with replication initiation regions (IR/MAR) can initiate gene amplification under permissive genetic conditions.
- These circles contribute significantly to cancer genome plasticity and evolution.
- The process can lead to the formation of double minutes (DMs) or homogeneously staining regions (HSR).
Conclusions:
- Extrachromosomal circles are critical mediators of oncogene amplification in human malignancies.
- Studying these circles is vital for advancing cancer diagnostics, therapeutics, and biotechnological applications like recombinant protein production.
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