Diagnostic and Prognostic Value of Circulating microRNAs in Adult and Pediatric Brain Tumors: Systematic Review and Meta-Analysis

Brain tumors remain among the most challenging malignancies in both adult and pediatric populations due to their heterogeneity, limited accessibility for biopsy, and variable clinical outcomes. Recently, circulating microRNAs (miRNAs) have emerged as promising minimally invasive biomarkers for cancer detection and prognosis. This systematic review and meta-analysis aimed to evaluate the diagnostic and prognostic value of circulating miRNAs in adult and pediatric brain tumors. A comprehensive literature search conducted across major electronic databases to identify eligible studies assessing circulating miRNAs in blood, serum, plasma, or cerebrospinal fluid of patients with primary brain tumors. Studies reporting diagnostic accuracy measures (sensitivity, specificity, area under the curve [AUC]) or survival outcomes (overall survival, progression-free survival, hazard ratios) were included. Data extracted and pooled using random-effects models. Study quality assessed using standardized appraisal tools. The meta-analysis demonstrated that circulating miRNAs exhibit significant diagnostic performance in differentiating brain tumor patients from healthy controls, with pooled sensitivity and specificity indicating moderate-to-high accuracy. Several miRNAs, including tumor-specific expression signatures, showed consistent upregulation or downregulation across gliomas, medulloblastomas, and other central nervous system tumors. Prognostically, elevated or reduced levels of specific circulating miRNAs were significantly associated with overall survival and disease progression, suggesting their potential role as independent prognostic indicators. Subgroup analyses revealed differences between adult and pediatric populations, reflecting underlying biological diversity. In conclusion, circulating miRNAs represent promising non-invasive biomarkers for the diagnosis and prognosis of brain tumors in both adults and children. However, heterogeneity in study design, sample processing, and analytical methods underscores the need for standardized protocols and large-scale prospective validation before clinical implementation.

کلیدواژه ها:

circulating microRNAs ، Brain tumors ، diagnostic biomarkers ، Prognostic biomarkers ، Meta-analysis