Comparative genomic hybridization analysis identifies gains of 1p35 similar to p36 and chromosome 19 in osteosarcoma

Osteosarcomas (OS) are aggressive tumors of the bone and often have a poor prognosis, Conventional cytogenetic analyses of OS have revealed highly com plex karyotypes, with numerous abnormalities. In this study, we analyzed 18 untreated OS tumors from 17 patients of the younger incidence age group by comparative genomic hybridization (CGH), 4 tumors by spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH). Comparative genomic hy bridization identified frequent copy number changes of the chromosomal regi on lp (10/17) and gain of part or all of chromosome 19(8/17). In addition g ains were observed at 5p(3/17), Sq(3/17), 16p(3/17), and 17p(5/17) and loss es at chromosomes 2q(3/17), 10(4/17) and 13(3/17). High level gains were de tected in the 8q23-q24 region in two tumors as well as at 17p in one primar y and a metastatic tumor. Minimal regions of gain were present at 1p35 simi lar to p36.3 (8/17): 5p14 similar to p15.2 (3/17), and 8q22 similar to q24. 3 (3/17). SKY analysis demonstrated that OS has a complex pattern of clonal and non-clonal rearrangements and helped confirm the structural basis for the imbalances detected by CGH. Spectral karyotyping confirmed an overall p attern of chromosomal gain affecting 1p in all four tumors. Fluorescence in situ hybridization analysis from these tumors confirmed the gain of the 1p 36 region in 2 tumors as determined by CGH analysis as well as the amplific ation of 8q. (C) 2001 Elsevier Science Inc. All rights reserved.