Анализ свободно циркулирующей ДНК в плазме у пациентов с острыми миелоидными лейкозами

BACKGROUND. A series of studies demonstrated that the analysis of plasma circulating cell-free DNA (cfDNA) in leukemia patients is an alternative to the estimation of minimal residual disease (MRD) in bone marrow for tumor monitoring and prognosis of the disease course. AIM. To assess the cfDNA concentration and integrity at various stages of acute myeloid leukemia (AML) treatment in real-world clinical practice. MATERIALS & METHODS. The study enrolled 26 AML patients and 8 sex- and age-matched relatively healthy subjects. The cfDNA was isolated from plasma collected in stabilization tubes using QIAamp MinElute ccfDNA Mini Kit. Plasma cfDNA concentration and integrity were determined with quantitative PCR using QuantStudio 5 in three repetitions producing two β-actin gene amplicons with the length of 106 and 384 base pairs. RESULTS. On the disease diagnosis date, plasma cfDNA concentration in leukemia patients is characterized by pronounced variability and positively correlates with the percentage of blast cells in bone marrow. Plasma cfDNA concentration in AML patients in remission is significantly lower (p = 0.046) than that at the disease onset. Plasma cfDNA concentration at the level of 9.33 ng/mL can discriminate between the samples of AML patients at disease onset and on achieving remission with 83.3 % sensitivity and 64.3 % specificity (p = 0,048). The cfDNA integrity index in MRD-positive patients is significantly higher than in healthy subjects (p = 0.006), AML patients at disease onset (p = 0.004) and in MRD-negative remission (p = 0.010). CONCLUSION. cfDNA is a promising biomarker in AML. During leukemia treatment, cfDNA concentration rates reflect dynamics of tumor size changing. Plasma cfDNA integrity index in AML patients can potentially yield a MRD marker and be used for assessing treatment efficacy and early relapse detection.