RT Journal Article SR Electronic T1 Amplification of KIT, PDGFRA, VEGFR2, and EGFR in Gliomas JF Molecular Cancer Research JO Mol Cancer Res FD American Association for Cancer Research SP 927 OP 934 DO 10.1158/1541-7786.MCR-06-0085 VO 4 IS 12 A1 Puputti, Marjut A1 Tynninen, Olli A1 Sihto, Harri A1 Blom, Tea A1 Mäenpää, Hanna A1 Isola, Jorma A1 Paetau, Anders A1 Joensuu, Heikki A1 Nupponen, Nina N. YR 2006 UL http://mcr.aacrjournals.org/content/4/12/927.abstract AB Receptor tyrosine kinase aberrations are implicated in the genesis of gliomas. We investigated expression and amplification of KIT, PDGFRA, VEGFR2, and EGFR in 87 gliomas consisting of astrocytomas, anaplastic astrocytomas, oligodendrogliomas, or oligoastrocytomas in tumor samples collected at the time of the diagnosis and in samples of the same tumors at tumor recurrence. Gene amplifications were investigated using either chromogenic in situ hybridization or fluorescence in situ hybridization, and protein expression using immunohistochemistry. In samples collected at glioma diagnosis, KIT and PDGFRA amplifications were more frequent in anaplastic astrocytomas than in astrocytomas, oligodendrogliomas, and oligoastrocytomas [28% versus 5% (P = 0.012) and 33% versus 2% (P = 0.0008), respectively]. VEGFR2 amplifications occurred in 6% to 17% of the gliomas at diagnosis, and EGFR amplifications in 0% to 12%. Amplified KIT was more frequently present in recurrent gliomas than in newly diagnosed gliomas (P = 0.0066). KIT amplification was associated with KIT protein expression and with presence of PDGFRA and EGFR amplifications both at the time of the first glioma diagnosis and at tumor recurrence, and with VEGFR2 amplification at tumor recurrence. Three (4%) primary gliomas and 10 (14%) recurrent gliomas that were evaluable for coamplification of KIT, PDGFRA, and VEGFR2 showed amplification of at least two of these genes; the amplicon contained amplified KIT in all 13 cases. In conclusion, besides glioblastoma, amplified KIT, PDGFRA, and VEGFR may also occur in lower-grade gliomas and in their recurrent tumors. It is currently not known whether specific tyrosine kinase inhibitors are effective in the treatment of such gliomas. (Mol Cancer Res 2006;4(12):927–34)