title: A novel C19MC amplified cell line links Lin28/let-7 to mTOR signaling in embryonal tumor with multilayered rosettes.
abstract: BACKGROUND
  Embryonal tumor with multilayered rosettes (ETMR) is an aggressive central nervous system primitive neuroectodermal tumor (CNS-PNET) variant. ETMRs have distinctive histology, amplification of the chromosome 19 microRNA cluster (C19MC) at chr19q13.41-42, expression of the RNA binding protein Lin28, and dismal prognosis. Functional and therapeutic studies of ETMR have been limited by a lack of model systems.
  
  
  METHODS
  We have established a first cell line, BT183, from a case of ETMR and characterized its molecular and cellular features. LIN28 knockdown was performed in BT183 to examine the potential role of Lin28 in regulating signaling pathway gene expression in ETMR. Cell line findings were corroborated with immunohistochemical studies in ETMR tissues. A drug screen of 73 compounds was performed to identify potential therapeutic targets.
  
  
  RESULTS
  The BT183 line maintains C19MC amplification, expresses C19MC-encoded microRNAs, and is tumor initiating. ETMRs, including BT183, have high LIN28 expression and low let-7 miRNA expression, and show evidence of mTOR pathway activation. LIN28 knockdown increases let-7 expression and decreases expression of IGF/PI3K/mTOR pathway components. Pharmacologic inhibition of the mTOR pathway reduces BT183 cell viability.
  
  
  CONCLUSIONS
  BT183 retains key genetic and histologic features of ETMR. In ETMR, Lin28 is not only a diagnostic marker but also a regulator of genes involved in growth and metabolism. Our findings indicate that inhibitors of the IGF/PI3K/mTOR pathway may be promising novel therapies for these fatal embryonal tumors. As the first patient-derived cell line of these rare tumors, BT183 is an important, unique reagent for investigating ETMR biology and therapeutics.
authors: Corresponding authors: Jennifer A. Chan, MD, Department of Pathology & Laboratory Medicine, University of Calgary, HRIC 2A25, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1. jawchan@ucalgary.ca); Annie Huang, MD, PhD, Division of Hematology-Oncology, Department of Pediatrics, The Hospital for Sick Children, TMDT, 11-401P, 101 College St., Toronto, Ontario, Canada M5G 1L7 (annie.huang@sickkids.ca.
authors: Tara
authors: T
authors: Spence
authors: Christian
authors: C
authors: Perotti
authors: Patrick
authors: P
authors: Sin-Chan
authors: Daniel
authors: D
authors: Picard
authors: Wei
authors: W
authors: Wu
authors: Anjali
authors: A
authors: Singh
authors: Colleen
authors: C
authors: Anderson
authors: Michael D
authors: MD
authors: Blough
authors: J Gregory
authors: JG
authors: Cairncross
authors: Lucie
authors: L
authors: Lafay-Cousin
authors: Douglas
authors: D
authors: Strother
authors: Cynthia
authors: C
authors: Hawkins
authors: Aru
authors: A
authors: Narendran
authors: Annie
authors: A
authors: Huang
authors: Jennifer A
authors: JA
authors: Chan
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018929:Cell Culture Techniques; D002675:Child, Preschool; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D056915:DNA Copy Number Variations; D005784:Gene Amplification; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D017404:In Situ Hybridization, Fluorescence; D007328:Insulin / Q000378:metabolism; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009373:Neoplasms, Germ Cell and Embryonal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018242:Neuroectodermal Tumors, Primitive / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D016601:RNA-Binding Proteins / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D023041:Xenograft Model Antitumor Assays
chemical_list: D014408:Biomarkers, Tumor; D007328:Insulin; D035683:MicroRNAs; D019869:Phosphatidylinositol 3-Kinases; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D058570:TOR Serine-Threonine Kinases; C000715187:Lin28A protein, human; C487931:mirnlet7 microRNA, human; C546842:MTOR protein, human
keywords: C19MC; ETANTR; ETMR; Lin28; mTOR