ABSTRACT
<p><b>OBJECTIVE</b>To investigate the deletion of p53 gene and amplification of HER-2 oncogene at chromosome 17 in primary hepatocellular carcinoma (HCC) and the clinical significance.</p><p><b>METHODS</b>Interphase dual fluorescence in situ hybridization (FISH) was applied to detect the ratio of the number of p53 gene copy or HER-2 oncogene copy to that of chromosome 17 copy, to determine the p53 gene deletion and HER-2 oncogene amplification in nuclei prepared from 42 surgical specimens of HCC. Statistical analysis for their clinical significance was performed.</p><p><b>RESULTS</b>Loss of p53 gene and amplification of HER-2 oncogene were detected in 27 (64.3%) and 9 (21.4%) of the 42 HCC respectively including 4 cases with low and 5 with high copy amplification. Six (14.3%) of 42 HCC showed simultaneously p53 gene deletion and HER-2 oncogene amplification. 61.9% (26/42) of HCC were polysomy 17, which correlated positively with p53 gene deletion (chi(2) = 12.286, P < 0.001). No close correlation between p53 gene loss and HER-2 oncogene amplification was found (chi(2) = 0.00, P = 1.00). Loss of p53 gene was related to the serum alpha-fetoprotein (AFP) level and the tumor size (P < 0.05). The postoperative 2-year survival rate (18.5%) of HCC patients with p53 gene deletion was significantly lower than postoperative 2-year survival rate (60.0%) of those without p53 gene loss (chi(2) = 7.467, P = 0.006). Meanwhile, HER-2 oncogene amplification showed a tendency of correlation with the tumor size (chi(2) = 2.973, P = 0.085), and the postoperative 2-year survival rate (0/9) of HCC patients with HER-2 oncogene amplification was significantly lower than those (42.4%) without HER-2 oncogene amplification (chi(2) = 3.977, P = 0.046).</p><p><b>CONCLUSION</b>There were a high frequency of p53 gene deletion and a low frequency of HER-2 oncogene amplification in primary HCC, which might be involved in initiation and development of a subset of primary HCC.</p>