title: Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications.
abstract: BACKGROUND
  Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies.
  
  
  RESULTS
  The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression.
  
  
  CONCLUSIONS
  Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.
authors.affiliation: EuroClone S.p.A Research Laboratory, Molecular Biotechnology Centre-MBC, University of Turin, Turin, Italy. c.zanini@euroclone.it
authors.forename: Cristina
authors.initials: C
authors.lastname: Zanini
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Ercole
authors.forename: Giorgia
authors.initials: G
authors.lastname: Mandili
authors.forename: Roberta
authors.initials: R
authors.lastname: Salaroli
authors.forename: Alice
authors.initials: A
authors.lastname: Poli
authors.forename: Cristiano
authors.initials: C
authors.lastname: Renna
authors.forename: Valentina
authors.initials: V
authors.lastname: Papa
authors.forename: Giovanna
authors.initials: G
authors.lastname: Cenacchi
authors.forename: Marco
authors.initials: M
authors.lastname: Forni
mesh_terms: D015415:Biomarkers; D045744:Cell Line, Tumor; D002465:Cell Movement; D006801:Humans; D016130:Immunophenotyping; D008527:Medulloblastoma / Q000378:metabolism* / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D010641:Phenotype; D025941:Protein Interaction Mapping; D060066:Protein Interaction Maps; D020543:Proteome; D040901:Proteomics / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D018874:Spheroids, Cellular; D014407:Tumor Cells, Cultured
chemical_list: D015415:Biomarkers; D020543:Proteome