Integrated Genomic Analysis Unveils MicroRNA Roles in Glioma Development

Gliomas are the most common type of primary brain tumors in adults, with a high level of recurrence and mortality. Their complex biology and adaptive resistance mechanisms pose major obstacles to existing treatment strategies. Non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs), are crucial in tumor development and progression. Small RNA sequencing technology was performed in 25 patients with high-grade gliomas (HGGs) to analyze ncRNA expression in gliomas compared to normal adjacent tissues (NATs) aiming to elucidate their possible roles in these malignancies. Samples from patients with gliomas were examined, revealing an overall upregulation of ncRNAs. Specific ncRNA classes, including miRNAs, transfer RNAs (tRNAs), Piwi-interacting RNAs (piRNAs), and small nucleolar RNAs (snoRNAs) showed notable shifts in abundance between tumor and normal samples. Among the upregulated miRNAs, a set of top five, such as miR-21, miR-221, miR-1321, miR-1306-5p, and miR-374a-5p, were validated by real-time quantitative PCR (RT-qPCR) in a cohort of 17 low-grade gliomas (LGGs) and 52 HGGs. These miRNAs are associated with critical oncogenic pathways and correlated with a worse prognosis. This study expanded the understanding of glioma biology and further confirmed the role of ncRNAs in the pathogenesis, supporting their potential use as novel possible biomarkers or therapeutic targets. Moreover, it provided an integrated analysis of multiple ncRNA classes, offering validation across both LGG and HGG, and uniquely incorporating a Kurdish cohort.