MUTATION OF P53 GENE IN HEPATOCELLULAR-CARCINOMA CELL-LINES WITH HBX DNA

It has been known that the incidence of p53 mutation is very rare in H EX-positive primary human hepatocellular carcinoma (HCC) tissues. The frequency of p53 mutation, however, in established cell lines with int egrated HEV DNA and/or HEX has not been well studied. To know p53 muta tional frequency, and to investigate whether the presence of HEX DNA s equence correlates with the absence of p53 mutation in the established HCC cell lines, we studied the p53 mutation and the presence of HEX s equence in IZ recently characterized HCC cell lines. As a result, all 12 (100%) lines showed mutation in the p53 gene. Three (25%) cell line s had transversion of codon 215 while no mutation of codon 249 was fou nd. In contrast with previous reports, although HEX DNA was present in 11 cell lines, p53 mutation had occurred, indicating that the presenc e of HEX viral DNA does not correlate with a lack of p53 mutation in e stablished HCC cell lines. Our results suggest that the frequency of p 53 mutation is extremely high even in HEX DNA positive HCC cell lines.