Gains and losses of DNA sequences in liposarcomas evaluated by comparative genomic hybridization

Comparative genomic hybridization (CGH) was used to detect and map the regions of gain, high‐level amplification, and loss of DNA sequences in 14 liposarcomas. Thirteen tumors showed DNA sequence copy number changes of one or more genomic regions (mean, six aberrations/tumor; range, 0–17). These aberrations were observed in almost every chromosome but some chromosomal regions were affected more often than others. DNA sequence gains were more frequent than losses. The most common gain was seen at 12q14‐21 (50% of tumors). Other frequent gains (29%) were of Iq21‐24, 8cen‐q21.2, 19q, and 20q. High‐level amplification was observed in six (43%) tumors and included as minimal common segments bands 12q15, Iq22, and Iq24. In five (36%) tumors, sequences at Iq21‐24 and Iq32 were found to be gained simultaneously with 12q14‐21, which means that in 71% of the tumors with gain at 12q, an increase of DNA sequence copy number at Iq was also observed. The most common losses of DNA sequences (21%) occurred from regions 9p21‐pter and 13q21‐qter. Most of the aforementioned regions have not previously been reported to be altered in liposarcomas. The detection of a novel recurring amplicon at Iq21‐24 with high‐level amplification at Iq22 and frequent simultaneous DNA sequence gain at 12q14‐21 (high‐level amplification at 12q15) suggests that genes linked to both these regions may play a significant role in the development and progression of liposarcomas. Genes Chromosom Cancer 15:89–94 (1996). © 1996 Wiley‐Liss, Inc.