effects of reduced mir-24 expression on plasma methotrexate levels, therapy-related toxicities,and patient outcomes in pediatric acute lymphoblastic leukemia

Background: the current study aims to investigate the relationship of mir-24 expression with plasma methotrexate (mtx) levels, therapy-related toxicities, and event-free survival (efs) in iranian pediatric acute lymphoblastic leukemia (all) patients.methods: the study included 74 all patients in consolidation phase and 41 healthy children. rna was extracted from plasma, polyadenylated, and reverse transcribed. mir-24 expression was determined by quantitative polymerase chain reaction (qpcr). plasma mtx concentrations were measured by high performance liquid chromatography (hplc) 48 h after high-dose methotrexate (hd-mtx) injection. the diagnosis of all was further subclassified as b-all or t-all via flow cytometry.results: mir-24 expression was less in pediatric all patients than in the control group (p = 0.0038). furthermore, downregulation of mir-24 was correlated with intermediate-to high-grade hd-mtx therapy toxicities (p = 0.025). nevertheless, no statistically significant associations were seen between mir-24 levels and plasma mtx levels 48 h after hd-mtx administration (p > 0.05) or efs in pediatric all patients (p > 0.05).conclusions: mir-24 expression may contribute to interindividual variability in response to intermediate-to high-grade hd-mtx therapy toxicities under berlin frankfurt munster (bfm) treatment.