DNA sequence copy number aberrations associated with histological subtypesand DNA ploidy in gastric carcinoma

We have analyzed DNA sequence copy number aberrations (DSCNAs) and DNA ploi dy by using comparative genomic hybridization and laser scanning cytometer in gastric carcinomas (GCs) to elucidate the genomic aberrations in relatio n to clinicopathological parameters. Thirty-two out of 33 cases showed one or more DSCNAs;vith a mean number of 11.7 per tumor. High-level gains were detected at 2p, 3q, 6p, 7p, 7q, 8q, 12p, 13q, 19q, and 20q. Frequency of gr oss genomic abnormalities and chromosome regions that have genomic aberrati ons were similar in both intestinal- and diffuse-type GCs, except aberratio ns at 8p, 9p, 12q, and 20q. The overall number of DSCNAs was significantly greater in DNA aneuploid tumors than that in DNA diploid tumors. We detecte d genomic aberrations characterized by histological subtype, tumor location , and DNA ploidy status: gain of 20q and losses of 8p and 9p in intestinal- type GCs, gains of 8p and 12q in diffuse-type GCS, gain of 20q in the lower third GCs, and loss of 5q, 9p, 10q, 16q, and 18q in DNA aneuploid GCs. Fur thermore, 5q loss is associated with DNA aneuploidy (P=0.0001) or the total number of losses (P=0.001,), gain+losses (P=0.004), and high-level gains ( P=0.001) in GCs. Among these loci, chromosome Sp was unique. Gain of 8p was more common in diffuse-type GC, whereas loss of 8p was more frequently det ected in intestinal-type GC. In conclusion, we describe chromosomal regions of 5q, 8p, and 20q, which are of interest for further investigation of GCs .