Background & Objective: Acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) are among the most common malignancies and leading causes of cancer-related morbidity in children. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression and have emerged as potential molecular biomarkers in hematologic malignancies. This study aimed to evaluate the expression level of miRNA-326 in pediatric patients with ALL and AML compared with healthy controls and to assess its potential utility as a molecular indicator in childhood acute leukemia.
 Materials & Methods:  This case–control study included 50 newly diagnosed pediatric patients with acute leukemia (ALL and/or AML) and 50 age- and sex-matched healthy controls. Peripheral blood samples were collected from patients during chemotherapy. Total RNA was extracted, and miRNA-326 expression levels were quantified using real-time quantitative reverse transcription PCR (qRT-PCR). U6 small nuclear RNA was used as an internal reference, and relative expression levels were calculated using the 2⁻ΔΔCt method. Statistical analysis was performed using unpaired t-tests.
Results:  The mean Ct value of miRNA-326 was significantly lower in leukemic patients than in healthy controls (28.53 ± 3.72 vs. 29.70 ± 1.57; P = 0.043), indicating reduced miRNA-326 expression in pediatric leukemia. Additionally, the negative log fold change (ΔΔCt) was significantly lower in the leukemia group compared with controls (−3.24 ± 3.59 vs. −0.05 ± 2.61; P < 0.001).
Conclusion:  miRNA-326 expression was significantly downregulated in pediatric patients with acute leukemia (ALL and AML) compared with healthy controls. These findings suggest that decreased miRNA-326 expression may serve as a potential molecular indicator in pediatric acute leukemia. However, further longitudinal and functional studies are required to clarify its diagnostic and prognostic significance.