Dix B, Robbins P, Carrello S, House A, Iacopetta B
University Department of Surgery, Sir Charles Gairdner Hospital, Nedlands, Western Australia.
Br J Cancer. 1994 Oct;70(4):585-90. doi: 10.1038/bjc.1994.355.
Immunocytochemistry (ICC) has been used routinely to stain for p53 overexpression in a range of human tumours. The underlying assumption has been that positive staining indicates a mutation in the p53 coding sequence. Recently, however, discordancy has been observed and the accuracy of ICC as a marker of p53 gene mutation has been questioned. In this study of 109 colorectal adenocarcinomas, we compared ICC staining with p53 gene mutations detected by single-strand conformation polymorphism (SSCP) analysis. Concordancy between the two techniques was found in 69% of tumours. ICC-positive/SSCP-negative cases accounted for 20% of tumours and ICC-negative/SSCP-positive cases for the remaining 11%. These results caution against the assumption that p53 protein overexpression is always associated with a gene mutation. Epigenetic phenomena may account for a significant proportion of ICC-positive tumours.
免疫细胞化学（ICC）已被常规用于在一系列人类肿瘤中检测p53的过表达。其潜在假设是阳性染色表明p53编码序列发生了突变。然而，最近已观察到不一致情况，并且ICC作为p53基因突变标志物的准确性受到了质疑。在这项对109例结肠腺癌的研究中，我们将ICC染色与通过单链构象多态性（SSCP）分析检测到的p53基因突变进行了比较。在69%的肿瘤中发现两种技术结果一致。ICC阳性/SSCP阴性的病例占肿瘤的20%，而ICC阴性/SSCP阳性的病例占其余的11%。这些结果警示不要假定p53蛋白过表达总是与基因突变相关。表观遗传现象可能是ICC阳性肿瘤的很大一部分原因。
