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目的研究中国高发区肝细胞癌（ＨＣＣ）ｐ５３基因２４９密码子高频度突变的规律性，为探寻癌变机制及基于ｐ５３的基因和免疫治疗提供依据。方法用巢式ＰＣＲ结合ＤＮＡ测序和限制性片段长度多态（ＲＦＬＰ）分析的方法，研究１９９４～１９９７年收集的９７例启东和２２例北京的肝细胞癌标本中，ｐ５３基因２４９密码子的突变率及突变的基因型。用免疫组化法研究癌及癌周细胞中ｐ５３蛋白的表达程度。结果１９９４～１９９７年，启东肝细胞癌中，ｐ５３基因２４９密码子的错义突变率继续保持在一个很高的水平，平均达到５３．６％（５２／９７），极显著地高于北京地区（０／２２）。２４９密码子为杂合型的样本，经癌组织富集后，均显示为突变的纯合子型。２４９密码子突变的ｐ５３蛋白在癌细胞核内高度积累，其阳性率达９５．２％（２０／２１），而在癌旁的肝组织中阳性率为０％（０／３５）。结论启东肝细胞癌中，ｐ５３基因发生着２４９密码子的持续性、纯合型的高频度错义突变，它伴随着ｐ５３蛋白在癌细胞核内较普遍的高度积累。这些特征为进一步了解癌变机制，并为基于ｐ５３的基因和免疫治疗提供了重要启示
OBJECTIVE: To study the regularity of high-frequency mutations in the 249 codons of hepatocellular carcinoma (HCC) p53 in high-risk areas in China, so as to provide basis for exploring the mechanism of canceration and p53-based genes and immunotherapy. METHODS: Nested PCR was used in combination with DNA sequencing and restriction fragment length polymorphism (RFLP) analysis to study mutations of the 249 codon of p53 gene in 97 cases of Qidong and 22 cases of hepatocellular carcinoma collected from 1994 to 1997. Rate and mutational genotypes. The degree of p53 protein expression in cancerous and pericancerous cells was studied by immunohistochemistry. Results From 1994 to 1997, the rate of missense mutation of the p53 gene codon 249 in Qidong hepatocellular carcinoma remained at a very high level, averaging 53.6% (52/97), which was significantly higher than that in Beijing. (0/22). The 249 codons were heterozygous samples that, after enrichment in cancerous tissue, all showed homozygous mutations. The 249 codon-mutant p53 protein was highly accumulated in the cancer cell nucleus, with a positive rate of 95.2% (20/21) and a positive rate of 0% (0/35) in the paracancerous liver tissue. Conclusions In Qidong hepatocellular carcinoma, the 249 codon-based high-frequency missense mutations of the p53 gene occur in the p53 gene, which is accompanied by a relatively high accumulation of p53 protein in the cancer cell nucleus. These features provide further insights into the mechanism of canceration and provide important insights for p53-based genes and immunotherapy.