Molecular Diagnosis & Therapy

, Volume 22, Issue 5, pp 515–522 | Cite as

Cell-Free eccDNAs: A New Type of Nucleic Acid Component for Liquid Biopsy?

  • Jing ZhuEmail author
  • Siyu Chen
  • Fan Zhang
  • Liang WangEmail author
Current Opinion


Extrachromosomal circular DNAs (eccDNAs) are circular DNAs that are originated from chromosomes, but are independent from chromosomal DNA. The eccDNAs are commonly found in various tissues and cell types, and in both normal and diseased conditions. Due to their highly heterogeneous origins and being widely spread in nearly all eukaryotes, the eccDNAs are believed to reflect the genome’s plasticity and instability. With the assistance of next-generation sequencing, more eccDNAs have been characterized at the molecular level. Recently, eccDNAs have been reported as cell-free DNAs in the circulation system. Importantly, these circulating eccDNAs have shown some evidence with disease associations, suggesting their potential utility as a new type of biomarker for disease detection, treatment assessment and progress surveillance. However, many challenges need to be addressed before implementing the eccDNAs as a new source of genetic material for liquid biopsy.


Compliance with Ethical Standards

Conflict of interest

The authors, JZ, SC, FZ and LW, disclose no potential conflicts of interest.


This study was partially supported by a National Institute of Health (R01CA212097) Grant to LW and National Natural Science Foundation of China (NSFC) (project# 81301752) and University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (project# UNPYSCT-2017056) Grants to JZ.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Laboratory of Medical GeneticsHarbin Medical UniversityHarbinChina
  2. 2.School of Computer Science and TechnologyHarbin Institute of TechnologyHarbinChina
  3. 3.Department of Pathology and MCW Cancer CenterMedical College of WisconsinMilwaukeeUSA

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