The mutation and expression of p53 gene in hepatocellular carcinoma

Objective: We and others have demonstrated that HBV X protein（HBx）can form complex with p53 protein Tumour specific mutations of the p53 gene often lead to the production of a mutated protein that has lost its normal growth regulatory functions In this paper, detection and comparison of mutated p53 and HBx in the liver tissue and PBMC from HCC patients were carried out to assess the extent of its involvement in hepatocarcinogenesis.Methods: DNA from HCC tissue samples was extracted and p53 mutation were detected at exon 5,6,7 and 8 by using PCR/SSCP and PCR/RFLP Using immunohistochemical method, p53 protein and HBx protein were detected in the HCC tissues.Results: PCR/SSCP analysis showed the presence of mutation at the exon 7 of p53 gene in 5 of 14 samples and the spot mutation of the 249 codon were identified by using PCR/RFCP The positive rate of p53 was 28 6% and HBx mutation in the liver tissues and PBMC from patients with HCC was 35 8% and 41 6% respectively Immunohistochemical analysis showed the positive rate of p53 protein was found in most of the HCC samples.Conclusion: These results indicated that the hotspot mutation of p53 gene in the samples studied is exon 7 The positive rate of p53 mutation and p53 protein were around 30%～40% But HBx was present in these smples at a much higher frequency The data suggested that the interactions between p53 and HBx are still worthy to be considered an important step in carcinogenesis