Chromosomal abnormalities of brain tumors - two years experience with cytogenetic analyses

Konference: 2010 6. sympózium a workshop molekulární patologie a histo-cyto-chemie

Kategorie: Nádorová biologie/imunologie/genetika a buněčná terapie

Téma: Postery

Číslo abstraktu: p012

Autoři: Mgr. Irena Urbanovská; M. Jalůvková; RNDr. Magdalena Uvírová; Doc.MUDr. Jana Dvořáčková, Ph.D., M.I.A.C; MUDr. Petr Buzrla; MUDr. Tomáš Paleček, Ph.D.

Primary brain tumors comprise about 1-2% of all tumors. Optimal therapeutic approach that significantly affects the prognosis of patients has not been found yet. It is expected that the therapy would be based among others on the knowledge of genetic changes in individual types of tumor by monitoring the chromosomal abnormalities.

Molecular cytogenetic studies have identified some of the genetic changes that underlie the pathologic differences among astrocytic tumors; progression in tumor grade is associated with an accumulation of aberrations.

We examined 136 primary brain tumor samples, 43 samples were glioblastomas, 25 samples were low grade astrocytomas, 6 tumor samples were anaplastic astrocytomas. The most frequent abnormalities include amplification of EGFR gene, polysomy of chromosome 7 and monosomy of chromosome 10. Other frequent chromosomal changes were deletions of tumor suppressor genes RB1 on chromosome 13, TP53 on chromosome 17 and CDKN2 on chromosome 9.

Then we examined 42 meningeomas and the most frequent abnormalities were deletions of 22q and 1p36 and then monosomy 14. The combination of deletion 1p36 and monosomy 14 is associated with higher risk of tumor recurrence and with worse prognosis.

In most cases, the results were in accordance with the clinical and histological findings and confirmed the original diagnosis. Some of the aberrations have predictive and prognostic value. In addition, the interdisciplinary co-operation of the brain surgeons, pathologists and geneticists is necessary to ensure that the material is sampled properly, the diagnosis is made correctly and quickly and that the risk of false negative findings is reduced.

Datum přednesení příspěvku: 23. 4. 2010