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Updated: Jul 11, 2025
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Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis
Published on: February 16, 2015
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Circulating cell-free DNA fragmentation is a stepwise and conserved process linked to apoptosis
Dandan Zhu1, Haihong Wang2, Wei Wu3
1Clinical Laboratories, Shenyou Bio, Zhengzhou, 450000, China.
BMC Biology
|November 12, 2023
Summary
Investigating circulating cell-free DNA (cfDNA) fragmentation reveals distinct profiles in cancer patients. This fragmentomics insight aids early cancer detection and monitoring during progression.
Area of Science:
- Molecular Biology
- Genomics
- Biochemistry
Background:
- Circulating cell-free DNA (cfDNA) comprises short DNA fragments, primarily from apoptotic cells.
- The exact physiological mechanisms of cfDNA fragmentation and its molecular characteristics are not fully understood.
- Understanding cfDNA processing is crucial for developing new diagnostic tools.
Purpose of the Study:
- To investigate the DNA fragmentation process and molecular profiles of cfDNA.
- To analyze cfDNA size distribution in various biological contexts.
Main Methods:
- Shallow whole-genome sequencing (sWGS) was employed to analyze DNA fragment size distribution.
- HL60 leukemia cell line undergoing apoptosis was used to study intracellular and extracellular cfDNA.
- Plasma cfDNA profiles were analyzed in healthy humans, dogs, and cancer patients.
Main Results:
- Distinct cfDNA size distribution profiles were observed in cell pellets versus supernatant, indicating stepwise fragmentation.
- A C-end preference was identified in both intracellular and extracellular cfDNA fragments.
- Cancer patients exhibited distinct cfDNA profiles compared to healthy individuals, with more short fragments and reduced C-end preference.
Conclusions:
- The study provides novel insights into the fragmentomics of circulating cfDNA.
- Findings suggest cfDNA profiles are conserved across mammals.
- This research has potential applications in early cancer diagnosis and monitoring cancer progression.
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