MicroRNA expression in pediatric intracranial ependymomas and their potential value for tumor grading

Abstract

Intracranial ependymoma represents one of the most common pediatric central nervous system malignancies, and exhibits a wide range of clinical behavior from relatively indolent lesions to highly malignant anaplastic ependymomas. Due to the heterogeneous nature of this disease there is lack of prognostic markers, which would reliably predict the outcome of patients. MicroRNAs (miRNAs) have emerged as important molecules in cancer biology during past decade; however, very little is known about their role in ependymomas. The aim of the present study was to evaluate expression of miRNAs in archived formalin-fixed paraffin-embedded (FFPE) samples of pediatric intracranial ependymomas. The expression of miRNAs were examined in 29 samples of ependymoma and we observed that miR-135a-3p, miR-137, miR-17-5p, miR-181d and let-7d-5p were upregulated. In addition, a significantly higher expression of miR-203a was detected in Grade III tumors suggesting its possible use as a prognostic or diagnostic marker. The present study also demonstrated that storage of (FFPE) ependymoma samples for >20 years did not result in a deterioration of miRNAs. The present findings broaden the presently available knowledge regarding miRNA expression in ependymomas and provide further evidence for the employment of miRNA analysis as a supplementary method for the morphological assessment of ependymoma samples. Materials and methods Patients and samples. A total of 29 formalin-fixed paraffin-embedded (FFPE) specimens of ependymomas were collected retrospectively from the archives of

Noncoding RNAs in pediatric brain tumors: Molecular functions and pathological implications

“…Another study also identified that the miR-135a-3p, miR-137, miR-17-5p, miR-181d, and let-7d-5p were upregulated in EPNs. 156 Low expression of miR-10a and high expression of miR-10b and miR-29a in EPN were also validated by qRT-PCR. 157 …”

“…Specifically, miR-17-5p, miR-19a-3p, miR-106b-5p, miR-124-3p, and miR-203a were shown to be differentially expressed between grade II and III EPNs. 156 , 158 , 159 These miRNAs were overexpressed in posterior fossa EPNs, including miR-106-b-5p and miR-19a-3p. 158 Moreover, miR-203, miR-17-5p, miR-124-3p, miR-192-5p, miR-221-3p, miR-222-3p, miR-326, miR-371a-5p, and miR-520g-3p were significantly correlated with tumor relapse.…”

Circulating exosomal microRNAs as diagnostic and prognostic biomarkers in patients with diffuse large B‐cell lymphoma

“…Both miR‐135a‐3p and miR‐4476 were reported to be upregulated miRNAs that promote cell proliferation, migration, and invasion in CNS tumors. 34 , 35 Further mechanistic analyses indicated that adenomatous polyposis coli, a negative regulator of the Wnt/β‐catenin signaling pathway, is a direct target of miR‐4476 and mediates the oncogenic effect of miR‐4476 in glioma. 35 This may explain high concentrations of these two miRNAs in DLBCL cases.…”

Circulating Exosomal MicroRNAs as Diagnostic and Prognostic Biomarkers in Patients with Diffuse Large B-cell Lymphoma

“…Both of miR-135a-3p and miR-4476 were reported as upregulated miRNAs that promoted cell proliferation, migration and invasion in CNS tumors (37,38). Further mechanistic analyses indicated the adenomatous polyposis coli(APC), a negative regulator of the Wnt/β-catenin signaling pathway, is a direct target of miR-4476 and mediated the oncogenic effect of miR-4476 in glioma (38).…”