Abstract Medulloblastoma (MB) is a leading cause of cancer-related deaths among children and young adults, accounting for over 20% of paediatric cancers. Current treatment options are limited, leading to unfavourable outcomes for affected children. Therefore, discovering new biomarkers is critical for improving MB management and prognosis. This study aimed to identify microRNA (miRNA) based therapies in paediatric medulloblastoma. To achieve this, RNA was extracted from eleven paediatric brain tissue samples (normal brain, n = 2; MB tissue, n = 8). High-throughput small-RNA sequencing (sRNA-seq) and bulk sequencing were conducted to identify the most deregulated miRNAs in MB tissue samples. Selected miRNAs, along with their gene targets and encoded proteins were further assessed in vitro and in patient samples using real-time polymerase chain reaction (RT-qPCR), and immunohistochemistry (IHC) (normal brain, n = 8; MB tissue, n = 20). Transient transfections and functional assays were conducted to understand the mechanisms underlying selected miRNAs and their roles in MB tumours. The sRNA-seq results revealed significant downregulation of miR-383 and miR-206 in MB samples, suggesting their potential role as tumour suppressors. Bioinformatics analysis using miRSystem and TargetScan and miRDB identified SV2B and CORO1C as direct targets of these miRNAs. Transcriptomic analysis confirmed the substantial upregulation of SV2B and CORO1C in MB tissue samples as compared to healthy individuals. IHC analysis showed significant overexpression of SV2B and CORO1C proteins in paediatric MB compared to normal brain tissue. Elevated CORO1C expression was also observed in adult MB samples (n = 23) compared to normal brain tissue. Functional assays demonstrated that miR-206 and miR-383 effectively targeted and downregulated CORO1C and SV2B, respectively. This led to reduced cell viability and impaired colony formation in MB cells (DAOY and D425). These findings emphasize the potential use of miRNA-mimic therapies for targeting MB. In conclusion, this study identified miR-206/CORO1C and miR-383/SV2B axes as highly promising therapeutic targets in MB.
Mustafov et al. (Fri,) studied this question.