Increased integrity of circulating cell-free DNA in plasma of patients with acute leukemia.
BACKGROUND
Increased cell-free DNA (cf-DNA) and the integrity of cf-DNA in plasma of patients with cancer has been described. We investigated the clinical utility of cf-DNA in the detection and monitoring of progression of leukemia.


METHODS
Plasma samples from 60 patients with acute leukemia were analyzed in comparison to plasma from 30 healthy controls. Plasma DNA was determined by quantitative PCR (qPCR) by amplifying the β-actin gene (ACTB). The DNA integrity index was calculated as the ratio of qPCR results (ACTB384/106). Paired diagnostic/complete remission (CR)/relapse samples from eight of 60 patients were analyzed, and the minimum residual disease (MRD) situations were monitored.


RESULTS
DNA concentrations (median: 8.80 ng/mL, p=0.004) and DNA integrity (median: 0.51, p<0.001) in cancer patients were significantly higher. Receiver operating characteristic (ROC) curve analysis showed that the area under the ROC curve of DNA and DNA integrity were 0.79 and 0.88, respectively. DNA integrity at CR had a distinct reduction and then an increase at relapse. DNA integrity in CR cases was higher than that observed in healthy controls.


CONCLUSIONS
Our preliminary data suggest that plasma DNA integrity is increased in acute leukemia and may be a potential biomarker for monitoring MRD. However, more work is needed.
Gao
Yu-Jie
YJ
Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Faculty of Laboratory Medicine, Chongqing Medical University, Chongqing, P.R. China.
He
Yu-Juan
YJ
Yang
Zai-Lin
ZL
Shao
Hui-Yuan
HY
Zuo
Yan
Y
Bai
Yao
Y
Chen
Hui
H
Chen
Xian-Chun
XC
Qin
Feng-Xian
FX
Tan
Shi
S
Wang
Jian
J
Wang
Li
L
Zhang
Ling
L
D000328:Adult; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics; D016022:Case-Control Studies; D002474:Cell-Free System; D004247:DNA / Q000097:blood* / Q000235:genetics; D018450:Disease Progression; D006801:Humans; D007938:Leukemia / Q000097:blood* / Q000175:diagnosis; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis; D055815:Young Adult
D014408:Biomarkers, Tumor; D004247:DNA