MicroRNA profiles as diagnostic tools in pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) represents the most common malignancy diagnosed in children, accounting for approximately 25-30% of all pediatric cancers. Despite remarkable improvements in survival rates over recent decades, with cure rates exceeding 90% in developed countries, the diagnosis and monitoring of ALL continue to rely on invasive bone marrow aspiration and morphological assessment. MicroRNAs (miRNAs), small non-coding RNA molecules that regulate gene expression post-transcriptionally, have emerged as promising biomarkers for cancer diagnosis and prognosis due to their stability in biological fluids, tissue-specific expression patterns, and regulatory roles in oncogenesis. This comprehensive review systematically examines the current evidence regarding miRNA expression profiles in pediatric ALL, focusing on their diagnostic potential, prognostic value, and applicability as non-invasive biomarkers. Aberrant miRNA expression has been consistently demonstrated in pediatric ALL, with specific signatures distinguishing B-cell precursor ALL from T-cell ALL, identifying cytogenetic subtypes, and predicting treatment response. Circulating miRNAs, particularly those packaged within exosomes, offer non-invasive alternatives for minimal residual disease monitoring and early relapse detection. Machine learning approaches integrating multi-miRNA panels have achieved high diagnostic accuracy, with several miRNAs, including miR-128-3p, miR-181a, miR-196b, miR-200c, and miR-326, demonstrating significant clinical utility. MicroRNA profiling represents a transformative approach to pediatric ALL management, offering enhanced diagnostic precision, improved risk stratification, and non-invasive monitoring capabilities. While challenges remain in standardizing detection methodologies and establishing clinically validated thresholds, the integration of miRNA biomarkers into clinical practice holds substantial promise for personalized medicine in childhood leukemia.