Upregulation of miR-20a and miR-106b is involved in the acquisition of malignancy of pediatric brainstem gliomas

Brainstem glioma (BSG) is an entity which commonly occurs in pediatric patients and carries a dismal prognosis. However, the category of adult BSG has displayed considerably benign biological behavior, thus providing a unique perspective to comparatively understand the malignant features of pediatric BSG. microRNAs (miRNAs) have been associated with cancer development and progression. To identify miRNAs specifically involved in the acquisition of malignant progression of pediatric BSG, we analyzed the miRNA expression profiles in orthotopic models which could simulate the BSG heterogeneity by microarrays. Our research revealed that miR-20a and miR-106b (known to be closely related) were the two most robust upregulated miRNAs in pediatric BSG compared to adult subtype. Furthermore, the two types of human BSG tissue were utilized to verify the microarray data by qRT-PCR and in situ hybridization. The results indicated good consistency with that of the microarray method. In conclusion, our studies provide evidence that miR-20a and miR-106b may serve as putative causative involvement of malignant progression of pediatric BSG, thereby serving as likely novel targets for constraining the rapid fatal course of pediatric BSG.