Otkrivanje delecije kromosoma 1 pomoću tehnike FISH na otiscima ependimoma ukazuje na regiju izvan kromosoma 22 važnu za recidiv tumora

Abstract

Ependymomas are glial tumors. They constitute approximately 5%-10% of intracranial tumors. Ependymomas are tumors which can recur. Predictive factors of outcome in ependymomas are not well established. Karyotypic studies are relatively scarce and loss of chromosome 22 has been described to correlate with recurrence. We are unaware of any reports involving chromosome 1 aberrations in the malignant progression of ependymomas. Cytogenetic analysis of 4 ependymomas was performed using double-target fluorescent in situ hybridization (FISH) and focusing on chromosomes 1 and 22. One patient had recurrent tumor. FISH was performed on 500 nuclei/tumors. All four cases showed a loss of chromosome 22q, while only one showed an additional loss of chromosome 1p, and it was the one with tumor relapse. We support the presence of tumor suppressor gene on 1p associated with relapse in ependymomas and suggest that the chromosome 1p status by FISH may identify a high risk group of patients harboring this tumor. Additional studies in this direction are needed, as our results refer to a minimal number of individuals analyzed.Ependimomi su glialni tumori. Oni čine otprilike 5%-10% intrakranijskih tumora. Ependimomi su tumori koji se mogu ponavljati. Čimbenici koji bi ukazivali na ishod ependimoma nisu dobro utvrđeni. Kariotipska ispitivanja su relativno rijetka, a opisano je kako gubitak kromosoma 22 korelira s ponovnom pojavom tumora. Nisu nam poznata izvješća o upletenosti aberacija kromosoma 1 u malignoj progresiji ependimoma. U ovoj studiji je citogenetska analiza 4 ependimoma provedena pomoću dvociljne fluorescentne in situ hibridizacije (FISH) i fokusiranja na kromosomima 1 i 22. U jednog se bolesnika radilo o ponovnoj pojavi tumora. FISH je izvedena na 500 jezgara/tumora. Sva četiri slučaja pokazala su gubitak kromosoma 22q, dok je samo jedan, i to onaj s ponovnim razvojem tumora, pokazao dodatni gubitak kromosoma 1p. Priklanjamo se mišljenju kako je prisutnost gena tumorske supresije na 1p udru žena s recidivom kod ependimoma i ukazujemo na to da bi status kromosoma 1p utvrđen pomoću FISH mogao identificirati visoko rizičnu skupinu bolesnika koji nose ovaj tumor. Potrebne su daljnje studije u ovom smjeru, jer se naši rezultati odnose na mali broj analiziranih osoba