Kim Hee Sung, Hong Eun Kyung, Park So Yeon, Kim Woo Ho, Lee Hye Seung
Department of Pathology, National Cancer Center, 809 Madu 1-dong, Ilsan-gu, Goyang, Gyeonggi, 411-764, Korea.
Anticancer Res. 2003 May-Jun;23(3C):2863-8.
beta-catenin plays an important role in the Wnt signaling pathway and the E-cadherin-catenin complex plays a critical role in the maintenance of normal tissue architecture. An alteration of any of the components of the E-cadherin-catenin complex is believed to result in the loss of cell-cell adhesion and to contribute to carcinogenesis. In order to evaluate such alterations in the gastric adenoma-carcinoma sequence, the abnormal expression of beta-catenin and E-cadherin and the mutations of beta-catenin exon 3 were studied. In the case of beta-catenin, nuclear immunoreactivity was noted in 17 (11.3%) out of 150 adenomas and 19 (17.1%) out of 111 carcinomas (p = 0.18). Among 51 gastric adenomas, no mutations were detected by direct sequencing analysis. The loss of membranous expression of both beta-catenin and E-cadherin linearly increased with tumor progression, however, beta-catenin loss was more frequent than E-cadherin. Our results show that the nuclear expression and membranous loss of beta-catenin without exon 3 mutation is relatively frequent in gastric adenomas. These suggest that alteration of other genes is primarily responsible for the nuclear translocation of beta-catenin in gastric adenomas.
β-连环蛋白在Wnt信号通路中发挥重要作用，而E-钙黏蛋白-连环蛋白复合物在维持正常组织结构中起关键作用。E-钙黏蛋白-连环蛋白复合物任何一个组分的改变都被认为会导致细胞间黏附丧失并促进癌变。为了评估胃腺瘤-癌序列中的此类改变，研究了β-连环蛋白和E-钙黏蛋白的异常表达以及β-连环蛋白外显子3的突变。就β-连环蛋白而言，在150个腺瘤中有17个（11.3%）以及在111个癌中有19个（17.1%）出现核免疫反应性（p = 0.18）。在51个胃腺瘤中，直接测序分析未检测到突变。β-连环蛋白和E-钙黏蛋白膜表达缺失随肿瘤进展呈线性增加，然而，β-连环蛋白缺失比E-钙黏蛋白更常见。我们的结果表明，在胃腺瘤中，无外显子3突变的β-连环蛋白核表达和膜缺失相对常见。这些提示，其他基因的改变是胃腺瘤中β-连环蛋白核转位的主要原因。
