Analysis of DNA methylation of isolated glands in gastric cancers and the surrounding the intestinal glands and non -intestinal glands

采用隐窝分离技术分析非化生性胃腺（NM）、肠化生腺（IM）和胃癌腺（GC）肿瘤相关基因的甲基化。取35例胃癌患者（肠型[n=22]，弥漫型[n=13]）的NM、IM和GC标本。分别从肿瘤、胃窦和身体上采集了3个样本。每个标本隐窝分离后，采用阿利新蓝和MUC5AC免疫双染色法将非癌腺分为NM腺、不完全肠化生腺（IIM）和完全肠化生腺（CIM）。通过联合Bislufite限制性分析（COBRA）检测8个基因（MLH1、p16、HPP1、RUNX3、ZFP64、RASSF2A、SFRP1、E-cadherin）的CpG岛超甲基化。IIM和CIM腺体的甲基化程度显著高于NM腺体。但IIM和CIM的甲基化状态无显著差异。甲基化GC腺和弥漫性GC腺无显著性差异。GC腺的甲基化水平显著高于相应的NM腺，而IM腺的甲基化水平无显著差异。目前关于NM腺、GIM腺和GC腺的数据表明，基因改变已经发生在周围的非癌性腺体中。肠型状况。

The crypt isolation technique was used to analysis methylation of tumor related genes of non-metaplastic g astric gland (NM), intestinal metaplasia gland (IM) and gastric cancer gland (GC). NM, IM and GC specimens were obtained from 35 patients with gastric cancer (intestinal type [n=22], diffuse type [n=13]). Three samples were obtained from cancer, antrum and body. After crypt isolation of each sample, the non-cancerous glands were classified into NM glands, incomplete intestinal metaplasia gland (IIM) and complete intestinal metaplasia gland (CIM) by double stain methods of alcian blue and MUC5AC immnostain. These samples were examined CpG island hypermethylation by Combine Bislufite Restriction Analysis (COBRA) for 8 genes (MLH1 , p16 , HPP1, RUNX3 , ZFP64 , RASSF2A, SFRP1, E-cadherin). IIM and CIM gland have significant higher methylation than NM gland. But, IIM and CIM had no significant differences in methylation status. The methylation GC gland and diffuse type GC gland had no significant differences. The methylation level of GC gland was significantly higher than corresponding NM gland, but no difference was observed in corresponding IM gland. The present data on NM gland, GIM gland and GC gland suggest that genetic alternations already occur within the surrounding noncancerous glands.status of intestinal type .