A novel minimally invasive diagnostic approach of various brain malignancies based on differential miRNA expression

Brain tumors are typically diagnosed after symptoms appear and requires definitive analysis of biopsy which takes a long time. Therefore, it is important to find markers for early diagnosis of different brain tumors. We aimed to validate and construct miRNA-based diagnostic panel for minimally-invasive differential diagnosis of brain tumors using plasma samples.

Circulating miRNAs were isolated from 67patients with glioblastoma, 33 with astrocytoma; 6 with oligodendroglioma; 33 with meningioma; 14 with lung cancer brain metastases and 25 with breast cancer brain metastases. Targeted and references miRNAs genetic expression was studied with RT-qPCR. Bioinformatics tools were used to develop diagnostic models and then functional enrichment for target genes and signalling pathways was conducted using KEGG, Reactome and WikiPathways databases.

Based on genetic expression of 10-miRNAs, validated models for differential diagnosis of each studied brain tumor were constructed. It was found that CASP3, EIF2S2, FYN, GNAQ, ITPR1, KPNB1, KREMEN1, MTOR, SREBF1, TYMS, VPS4B, and WASL were the most significant target genes of these miRNAs.

This study is among the first to include the three types of malignant brain tumors in addition to the benign brain tumor and also two types of secondary brain tumors. Results could be used as a minimally-invasive approach for early detection and monitoring recurrence of primary and metastatic brain lesions.