Mutational Screening of miR-17-92 Cluster and miR-34a by DNA Sequencing in Childhood High-Grade Brain Tumors

Abstract

OBJECTIVEThe miR-17-92 cluster and miR-34a are short non-coding RNAs, which are important in tumorigenesisas they regulate numerous oncogenes and tumor suppressor genes. This study aimed to investigate theassociations of mutations/polymorphisms of the miR-17-92 cluster and miR-34a coding sequences withhigh-grade central nervous system malignancies in pediatric patients.METHODSThis study included 53 children with central nervous system malignancies and age- and gender-matched27 healthy volunteers. Genomic DNAs were extracted from the paraffin-embedded tumor tissues (n=53)and peripheral blood samples (n=15) in the patient group and from the peripheral blood samples in thecontrol group and were analyzed for mutations/polymorphisms of the miR-17-92 cluster and miR-34acoding sequences by DNA sequencing method.RESULTSThere were no copy number alterations, amplifications, deletions, insertions, duplications, rearrangements, single nucleotide polymorphisms or mutations in the miR-17-92 cluster and miR-34a coding sequences of tumor tissue or blood samples in the patient group and of blood samples in the control group.CONCLUSIONIn children with high-grade brain tumors, no mutation was detected, leading to failures in regulations ofmiRNA coding DNA sequences of miR-17-92 and miR-34a. Further studies are needed to elucidate extremely complicated mechanisms underlying oncogenesis in high-grade central nervous system tumors.