title: Mutational profiling of kinases in glioblastoma.
abstract: BACKGROUND
  Glioblastoma is a highly malignant brain tumor for which no cure is available. To identify new therapeutic targets, we performed a mutation analysis of kinase genes in glioblastoma.
  
  
  METHODS
  Database mining and a literature search identified 76 kinases that have been found to be mutated at least twice in multiple cancer types before. Among those we selected 34 kinase genes for mutation analysis. We also included IDH1, IDH2, PTEN, TP53 and NRAS, genes that are known to be mutated at considerable frequencies in glioblastoma. In total, 174 exons of 39 genes in 113 glioblastoma samples from 109 patients and 16 high-grade glioma (HGG) cell lines were sequenced.
  
  
  RESULTS
  Our mutation analysis led to the identification of 148 non-synonymous somatic mutations, of which 25 have not been reported before in glioblastoma. Somatic mutations were found in TP53, PTEN, IDH1, PIK3CA, EGFR, BRAF, EPHA3, NRAS, TGFBR2, FLT3 and RPS6KC1. Mapping the mutated genes into known signaling pathways revealed that the large majority of them plays a central role in the PI3K-AKT pathway.
  
  
  CONCLUSIONS
  The knowledge that at least 50% of glioblastoma tumors display mutational activation of the PI3K-AKT pathway should offer new opportunities for the rational development of therapeutic approaches for glioblastomas. However, due to the development of resistance mechanisms, kinase inhibition studies targeting the PI3K-AKT pathway for relapsing glioblastoma have mostly failed thus far. Other therapies should be investigated, targeting early events in gliomagenesis that involve both kinases and non-kinases.
authors.affiliation: Department of Oncology, University of Torino, SP 142, Km 3,95, Candiolo, Torino, 10060, Italy; Candiolo Cancer Institute - FPO, IRCCS, Candiolo, Torino, Italy. f.e.bleeker@amc.uva.nl.
authors.forename: Fonnet E
authors.initials: FE
authors.lastname: Bleeker
authors.forename: Simona
authors.initials: S
authors.lastname: Lamba
authors.forename: Carlo
authors.initials: C
authors.lastname: Zanon
authors.forename: Remco J
authors.initials: RJ
authors.lastname: Molenaar
authors.forename: Theo J M
authors.initials: TJ
authors.lastname: Hulsebos
authors.forename: Dirk
authors.initials: D
authors.lastname: Troost
authors.forename: Angela A
authors.initials: AA
authors.lastname: van Tilborg
authors.forename: W Peter
authors.initials: WP
authors.lastname: Vandertop
authors.forename: Sieger
authors.initials: S
authors.lastname: Leenstra
authors.forename: Cornelis J F
authors.initials: CJ
authors.lastname: van Noorden
authors.forename: Alberto
authors.initials: A
authors.lastname: Bardelli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D004252:DNA Mutational Analysis; D005260:Female; D020558:GTP Phosphohydrolases / Q000235:genetics; D005909:Glioblastoma / Q000201:enzymology* / Q000235:genetics*; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics; D020935:MAP Kinase Signaling System; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D009154:Mutation; D051059:PTEN Phosphohydrolase / Q000235:genetics; D010770:Phosphotransferases / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D055815:Young Adult
chemical_list: D008565:Membrane Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; C538784:IDH2 protein, human; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human; D010770:Phosphotransferases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human; D020558:GTP Phosphohydrolases; C579846:NRAS protein, human