Liu Gui-Sheng, Gong Jun, Cheng Peng, Zhang Jun, Chang Ying, Qiang Lei
Department of Gastroenterology, The Second Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P. R. China.
Ai Zheng. 2006 Feb;25(2):185-9.
BACKGROUND & OBJECTIVE: Intestinal metaplasia (IM) is thought as the precancerous lesion of gastric carcinoma, and CDX2 gene plays important roles in development and differentiation of intestinal epithelium, and maintenance of intestinal phenotype. Recent studies found that CDX2 were expressed aberrantly in IM of chronic atrophic gastritis (CAG) and some gastric carcinomas, which implied that CDX2 may play an important role in IM formation and gastric carcinogenesis. This study was to investigate the roles of CDX2 in the development and progression of IM and gastric carcinogenesis, and determine the correlation of IM to gastric carcinogenesis.
A tissue microarray containing 46 cases of CAG with IM, 40 cases of gastric carcinoma, and 32 cases of IM foci in paracancerous tissues was constructed. High iron diamine/alcian blue (HID/AB) and HE staining were used to classify IM and gastric carcinoma, and the expression of CDX2 protein and mRNA in different gastric lesions was assessed with immunohistochemistry and in situ hybridization, respectively.
The proportion of type III IM was significantly higher in IM foci in paracancerous tissues than in CAG with IM (56.25% vs. 21.74%, P<0.01). The positive rates of CDX2 protein were 69.56% in IM foci in CAG, 53.13% in IM foci in paracancerous tissues, and 42.50% in gastric carcinomas, and the positive rates of CDX2 mRNA were 63.04%, 46.87%, and 35.00%, respectively. The positive rates were significantly lower in gastric cancer than in IM in CAG (P<0.01), but there was no significant difference between gastric cancer and IM foci in paracancerous tissues (P>0.05). The expression of CDX2 protein and mRNA was significantly higher in intestinal-type gastric cancer than in diffuse-type gastric cancer (54.55% vs. 27.78%, 45.45% vs. 22.22%, P<0.05). The expression of CDX2 protein was significantly lower in type III IM than in type I IM (46.42% vs. 79.31%, P<0.05).
CDX2 may play important roles in the development and progression of IM and gastric carcinogenesis.
肠化生（IM）被认为是胃癌的癌前病变，CDX2基因在肠上皮的发育、分化及肠表型维持中发挥重要作用。近期研究发现，CDX2在慢性萎缩性胃炎（CAG）肠化生及部分胃癌中表达异常，提示CDX2可能在肠化生形成及胃癌发生中起重要作用。本研究旨在探讨CDX2在肠化生发展及进展以及胃癌发生中的作用，并确定肠化生与胃癌发生的相关性。
构建包含46例伴有肠化生的CAG、40例胃癌及32例癌旁组织中肠化生灶的组织芯片。采用高铁二胺/阿尔辛蓝（HID/AB）及苏木精-伊红（HE）染色对肠化生及胃癌进行分类，分别用免疫组化和原位杂交法检测不同胃病变中CDX2蛋白及mRNA的表达。
癌旁组织中肠化生灶III型肠化生的比例显著高于伴有肠化生的CAG（56.25% 对21.74%，P<0.01）。CAG中肠化生灶CDX2蛋白阳性率为69.56%，癌旁组织中肠化生灶为53.13%，胃癌中为42.50%；CDX2 mRNA阳性率分别为63.04%、46.87%和35.00%。胃癌中的阳性率显著低于CAG中的肠化生（P<0.01），但胃癌与癌旁组织中肠化生灶之间无显著差异（P>0.05）。肠型胃癌中CDX2蛋白和mRNA的表达显著高于弥漫型胃癌（54.55%对27.78%，45.45%对22.22%，P<0.05）。III型肠化生中CDX2蛋白的表达显著低于I型肠化生（46.42%对79.31%，P<0.05）。
CDX2可能在肠化生发展及进展以及胃癌发生中起重要作用。
