DELETION MAPPING OF CHROMOSOME 4Q IN HEPATOCELLULAR-CARCINOMA

Hepatocellular carcinoma (HCC) frequently shows a loss of heterozygosi ty (LOH) on chromosome 4q. In order to define the commonly affected re gion on chromosome 4q for further positional cloning of the putative t umor suppressor gene, we carried out allelic imbalance (Al) studies in 41 HCCs using a panel of 43 microsatellite markers. Thirty-four cases (82.9%) showed Al at one or more loci. Detailed deletion mapping iden tified 7 independent, frequently deleted regions on this chromosome ar m. These were the (I) D4S1615 locus, (2) D4S1598 locus, (3) D4S620 loc us, (4) D4S1566 and D4S2979 loci, (5) D4S1617 and D4S1545 loci, (6) D4 S1537 locus; and (7) from the D4S2920 to D4S2954 locus. Among these 7 frequently deleted regions, 5 were associated with tumor differentiati on. Our results suggest that several putative tumor suppressor genes m ay be present on chromosome 4q and that the Al of chromosome 4q may pl ay a role in the aggressive progression of HCC. Int. J. Cancer (Pred. Oncol.) 79:356-360, 1998. (C) 1998 Wiley-Liss, Inc.