title: Differentially Expressed MicroRNAs in Meningiomas Grades I and II Suggest Shared Biomarkers with Malignant Tumors.
abstract: Meningiomas represent the most common primary tumors of the central nervous system, but few microRNA (miRNA) profiling studies have been reported so far. Deep sequencing of small RNA libraries generated from two human meningioma biopsies WHO grades I (benign) and II (atypical) were compared to excess dura controls. Nineteen differentially expressed miRNAs were validated by RT-qPCR using tumor RNA from 15 patients and 5 meninges controls. Tumor suppressor miR-218 and miR-34a were upregulated relative to normal controls, however, miR-143, miR-193b, miR-451 and oncogenic miR-21 were all downregulated. From 10 selected putative mRNA targets tested by RT-qPCR only four were differentially expressed relative to normal controls. PTEN and E-cadherin (CDH1) were upregulated, but RUNX1T1 was downregulated. Proliferation biomarker p63 was upregulated with nuclear localization, but not detected in most normal arachnoid tissues. Immunoreactivity of E-cadherin was detected in the outermost layer of normal arachnoids, but was expressed throughout the tumors. Nuclear Cyclin D1 expression was positive in all studied meningiomas, while its expression in arachnoid was limited to a few trabecular cells. Meningiomas of grades I and II appear to share biomarkers with malignant tumors, but with some additional tumor suppressor biomarkers expression. Validation in more patients is of importance.
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. raafat.el-gewely@uit.no.
authors.forename: Mohamed Raafat
authors.initials: MR
authors.lastname: El-Gewely
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. morten.andreassen@gmail.com.
authors.forename: Morten
authors.initials: M
authors.lastname: Andreassen
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. mari.walquist@uit.no.
authors.forename: Mari
authors.initials: M
authors.lastname: Walquist
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. anita.ursvik@uit.no.
authors.forename: Anita
authors.initials: A
authors.lastname: Ursvik
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. erik.knutsen@uit.no.
authors.forename: Erik
authors.initials: E
authors.lastname: Knutsen
authors.affiliation: Department of Clinical Medicine, Women's Health and Perinatology Research Group, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. mona.nystad@unn.no.|Department of Obstetrics and Gynecology, University Hospital of North Norway, NO-9038 Tromsø, Norway. mona.nystad@unn.no.|Department of Medical Genetics, Division of Child and Adolescent Health, University Hospital of North Norway, NO-9038 Tromsø, Norway. mona.nystad@unn.no.
authors.forename: Mona
authors.initials: M
authors.lastname: Nystad
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. dag.coucheron@uit.no.
authors.forename: Dag H
authors.initials: DH
authors.lastname: Coucheron
authors.affiliation: Department of Pathology, University Hospital of North Norway, NO-9038 Tromsø, Norway. kristin.smistad.myrmel@unn.no.
authors.forename: Kristin Smistad
authors.initials: KS
authors.lastname: Myrmel
authors.affiliation: Department of Neurosurgery, University Hospital of North Norway, NO-9038 Tromsø, Norway. rune.otto.hennig@unn.no.|Department of Clinical Medicine, Division of Neurosurgery, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. rune.otto.hennig@unn.no.
authors.forename: Rune
authors.initials: R
authors.lastname: Hennig
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, NO-9037 Tromsø, Norway. steinar.johansen@uit.no.|Marine Genomics Group, Faculty of Biosciences and Aquaculture, Nord University NO-8049 Bodø, Norway. steinar.johansen@uit.no.
authors.forename: Steinar D
authors.initials: SD
authors.lastname: Johansen
keywords: RT-qPCR; SOLiD deep sequencing; cap cells and Immunohistochemistry (IHC); meningioma; miRNA