Frequent loss of heterozygosity on chromosome 22 in hepatocellular carcinoma.

We investigated 24 hepatocellular carcinomas in Japan to find loss of heterozygosity with 15 polymorphic DNA markers that detect allelic losses at specific chromosome loci. Loss of heterozygosity on chromosomes 10q, 17p and 22q was detected in 3 of 12 (25%), 9 of 21 (43%) and 5 of 15 (33%) informative cases of hepatocellular carcinoma, respectively. This is the first report of loss of heterozygosity on chromosome 22q in hepatocellular carcinoma; the newly recognized common chromosome loss was considered to exist between D22S9 and D22S10 on 22q11. On the basis of this and other studies, we believe it is likely that such a chromosome loss in hepatocellular carcinoma is a signal for malignant transformation and that loss of unknown genes on chromosomes 10q, 17p and 22q may contribute to tumor progression in hepatocellular carcinoma.