Plasma cell-free DNA in patients with acute promyelocytic leukemia treated with arsenic trioxide

Cell-free DNA (cfDNA) is free DNA found in circulating blood that originates from apoptosis or necrosis, and elevated cfDNA concentrations have been reported in cancers and other diseases. In this study, the concentrations and fragment distributions of plasma cfDNA were investigated in elderly (n = 1) and pediatric (n = 1) patients with acute promyelocytic leukemia (APL) treated with arsenic trioxide (ATO). A slight increase in cfDNA concentrations was observed in the APL patients compared with healthy controls. In the elderly APL patient, the plasma cfDNA concentration increased with treatment duration, and significant positive correlations were observed between the plasma total arsenic concentration and cfDNA concentration during the first consolidation therapy. Ladder fragments (150–200bp, 300–400 bp, and 500–600 bp) were observed in a portion of plasma cfDNA from both APL patients. Moreover, APL-related gene mutations (FMS-like tyrosine kinase 3 internal tandem duplication, GATA-binding protein 2 gene, Janus-associated kinase 2 gene, Wilms’ tumor 1 gene, Kirsten-ras gene, and neuroblastoma-ras gene) were successfully genotyped from plasma cfDNA by using polymerase chain reaction-based methods. The findings of this study provide fundamental information on cfDNA from APL patients treated with ATO.