MicroRNAs in Cerebrospinal Fluid as Biomarkers in Brain Tumor Patients

Abstract

Backround: Although central nervous system (CNS) tumors are not the most common cancers, their incidence rate is constantly growing. Unfortunately, this group of cancers is characterized by a very poor prognosis with a very short average patient survival. Appropriate therapy depends on early and accurate diagnosis. However, this is often limited by brain tumor localization and heterogeneity. Therefore, new diagnostic approaches and biomarkers that are robust, sensitive, specifi c, and also without need of invasive biopsy, are still being sought. Cerebrospinal fl uid (CSF) comes into direct contact with the CNS and becomes a suitable source of biological material that could refl ect actual state of CNS. Suitable molecules in this regard appear to be microRNAs (miRNAs), short non-coding RNAs, that have been already detected in CSF and whose dysregulated levels are associated with various types of brain tumors. Purpose: Unfortunately, the methodical approaches used for CSF miRNA analysis have not been suffi - ciently standardized yet. For this reason, we summarize and evaluate methodical approaches which were previously used for miRNA analysis from CSF in order to fi nd the most appropriate ones. Subsequently, we review studies focused on miRNA with potential to become biomarkers of CNS tumors in the future.