SNP Array Analysis Reveals Novel Genomic Abnormalities Including Copy Neutral Loss of Heterozygosity in Anaplastic Oligodendrogliomas

作者:Idbaih Ahmed*; Ducray Francois; Dehais Caroline; Courdy Celia; Carpentier Catherine; de Bernard Simon; Uro Coste Emmanuelle; Mokhtari Karima; Jouvet Anne; Honnorat Jerome; Chinot Olivier; Ramirez Carole; Beauchesne Patrick; Benouaich Amiel Alexandra; Godard Joel; Eimer Sandrine; Parker Fabrice; Lechapt Zalcman Emmanuelle; Colin Philippe; Loussouarn Delphine; Faillot Thierry; Phong Dam Hieu; Elouadhani Hamdi Selma; Bauchet Luc; Langlois Olivier; Le Guerinel Caroline
来源:PLos One, 2012, 7(10): e45950.
DOI:10.1371/journal.pone.0045950

摘要

Anaplastic oligodendrogliomas (AOD) are rare glial tumors in adults with relative homogeneous clinical, radiological and histological features at the time of diagnosis but dramatically various clinical courses. Studies have identified several molecular abnormalities with clinical or biological relevance to AOD (e.g. t(1;19)(q10;p10), IDH1, IDH2, CIC and FUBP1 mutations). To better characterize the clinical and biological behavior of this tumor type, the creation of a national multicentric network, named %26quot;Prise en charge des OLigodendrogliomes Anaplasiques (POLA),%26apos;%26apos; has been supported by the Institut National du Cancer (InCA). Newly diagnosed and centrally validated AOD patients and their related biological material (tumor and blood samples) were prospectively included in the POLA clinical database and tissue bank, respectively. At the molecular level, we have conducted a high-resolution single nucleotide polymorphism array analysis, which included 83 patients. Despite a careful central pathological review, AOD have been found to exhibit heterogeneous genomic features. A total of 82% of the tumors exhibited a 1p/19q-co-deletion, while 18% harbor a distinct chromosome pattern. Novel focal abnormalities, including homozygously deleted, amplified and disrupted regions, have been identified. Recurring copy neutral losses of heterozygosity (CNLOH) inducing the modulation of gene expression have also been discovered. CNLOH in the CDKN2A locus was associated with protein silencing in 1/3 of the cases. In addition, FUBP1 homozygous deletion was detected in one case suggesting a putative tumor suppressor role of FUBP1 in AOD. Our study showed that the genomic and pathological analyses of AOD are synergistic in detecting relevant clinical and biological subgroups of AOD.

  • 出版日期2012-10-10