Detection of chromosomal imbalances in central neurocytomas by using comparative genomic hybridization

Object. Central neurocytomas are rare neuronal tumors commonly found in the intraventricular regions. Little is known about the tumorigenesis of these neoplasms. The aim of this study was to provide an overview of genetic imb alances in central neurocytomas. Methods. In this study, comparative genomic hybridization was used to ident ify DNA sequence copy number changes (losses and gains) in a series of 10 c entral neurocytomas. Tumor DNA and normal reference DNA were differentially labeled and allowed to cohybridize to normal metaphase chromosomes. After hybridization and fluorescent staining of the bound DNA, regions of gain or of loss of DNA sequences were detected as changes in the tumor/normal fluo rescence intensity ratio along the target metaphase chromosomes. A gain of DNA sequence was detected in chromosomes 2p, 10q, and 18q. A protooncogene, Bcl2, which maps to 18q21, was evaluated by immunohistochemical analysis t o determine its role in the formation of central neurocytomas. Conclusions. In this study the authors identified recurrent: genetic change s on chromosomes 2p, 10q, and 18q in central neurocytomas and highlighted c hromosomal regions for additional mapping and cloning of candidate genes th at are important in the development of central neurocytomas.