Frequent loss of heterozygosity on chromosome 4 in human hepatocellular carcinoma

Objective Few previous studies have shown high frequency of loss of heterozygosity (LOH) on chromosome 4q in hepatocellular carcinoma (HCC). We define more clearly the deletion regions that may harbor the putative tumor suppressor genes in HCC. Methods Forty eight cases of HCC and their corresponding non tumor liver tissues were investigated with 12 microsatellite polymorphic markers for LOH. Results Twenty one of 48 (44%) and 30 of 48 (63%) tumors showed LOH on at least one locus on the short and the long arms respectively. Two distinct common deleted regions (CDR) with different patterns of deletion were identified. The first CDR was located on 4q22 q25, between loci D4S392 and D4S1625. In addition, 17 of 27 (63%) of the informative tumors showed LOH on this region with locus D4S406 and constituted the highest rate of LOH on chromosome 4. The second CDR was located at 4q27 q31, between loci D4S1625 and D4S1652. Conclusion There are at least two tumor suppressor loci on 4q.