title: MicroRNA profiling of low-grade glial and glioneuronal tumors shows an independent role for cluster 14q32.31 member miR-487b.
abstract: Low-grade (WHO I-II) gliomas and glioneuronal tumors represent the most frequent primary tumors of the central nervous system in children. They often have a good prognosis following total resection, however they can create many neurological complications due to mass effect, and may be difficult to resect depending on anatomic location. MicroRNAs have been identified as molecular regulators of protein expression/translation that can repress multiple mRNAs concurrently through base pairing, and have an important role in cancer, including brain tumors. Using the NanoString digital counting system, we analyzed the expression levels of 800 microRNAs in nine low-grade glial and glioneuronal tumor types (n=45). A set of 61 of these microRNAs were differentially expressed in tumors compared with the brain, and several showed levels varying by tumor type. The expression differences were more accentuated in subependymal giant cell astrocytoma, compared with other groups, and demonstrated the highest degree of microRNA repression validated by RT-PCR, including miR-129-2-3p, miR-219-5p, miR-338-3p, miR-487b, miR-885-5p, and miR-323a-3p. Conversely, miR-4488 and miR-1246 were overexpressed in dysembryoplastic neuroepithelial tumors compared with the brain and other tumors. The cluster 14q32.31 member miR-487b was variably under-expressed in pediatric glioma lines compared with human neural stem cells. Overexpression of miR-487b in a pediatric glioma cell line (KNS42) using lentiviral vectors led to a decrease in colony formation in soft agar (30%) (P<0.05), and decreased expression of known predicted targets PROM1 and Nestin (but not WNT5A). miR-487b overexpression had no significant effect on cell growth, proliferation, sensitivity to temozolomide, migration, or invasion. In summary, microRNA regulation appears to have a role in the biology of glial and glioneuronal tumor subtypes, a finding that deserves further investigation.
authors.affiliation: Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Heather Marion
authors.initials: HM
authors.lastname: Ames
authors.affiliation: Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: Yuan
authors.affiliation: Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.|Department of Cellular and Tissue Biology, Universidad Nacional Autónoma de México, Mexico City, DF, USA.
authors.forename: Maria Adelita
authors.initials: MA
authors.lastname: Vizcaíno
authors.affiliation: Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Wayne
authors.initials: W
authors.lastname: Yu
authors.affiliation: Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.|Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Fausto J
authors.initials: FJ
authors.lastname: Rodriguez
mesh_terms: D000071916:AC133 Antigen / Q000235:genetics / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007223:Infant; D008297:Male; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D060787:Neoplasm Grading; D064231:Nestin / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: D000071916:AC133 Antigen; C568526:MIRN487 microRNA, human; D035683:MicroRNAs; D064231:Nestin; C000606023:PROM1 protein, human