MG_7抗原在胃肠癌的定位研究

本文应用免疫组化及免疫电镜技术对62例胃肠癌标本进行了原位MG_7抗原定位观察。结果显示80.77%(21/26例)的胃癌和94.44%(34/36例)的结直肠癌呈MG_7抗原阳性,该抗原的表达强度和存在部位与肿瘤的分化程度有一定相关。超微结构水平定位观察表明:在分化好的癌细胞、MG_7抗原主要位于腺腔缘微绒毛、细胞膜及膜下胞浆內;而在低分化癌细胞MG_7抗原主要位于分泌颗粒与合成及转运蛋白质的细胞器(包括內质网,高尔基复合体及其分泌小泡)內崾綧G_7抗原是胃肠癌细胞合成的一种分泌性物质。文中还对其定位特点与细胞分化程度的内在联系及其临床意义进行了探讨。

THE STUDY ON LOCALIZATION OF MG_7 ANTIGEN IN GASTROINTESTINAL CARCINOMA

Localization of MG_7 antigen was investigated in situ by immunohistochemic and immunoclectron microscopic technique in 62 cases of gastrointestinal carcinoma (GICA). The detective rate of MG_7 antigen was 80. 77% in gastric carcinoma (21/26 cases) and 94.44% in colorectal carcinoma (34/36 cases). Its expressing intensity and distribution were associatcd with the differentiation of tumor cells. Most of the poorly differentiated tumors showed much stronger MG_7 antigen expression and cytoplasmic staining, while most of the differentiated tumors showed membranic or mixed staining, mainly distributed in lumen side. Immunoelectronimicroscopic study revealed that MG_7 antigen predominantly existed in lumen margin microvilli, cell membrane and cytoplasm bencath the cell membrane in well differentiated tumor cells, existed in secretory granules, Golgicomplex and endoplasmic reticulum in poorly differetiatd tumor cells. The finding suggest that MG_7 antigen be a kind of secretory substance syntheszed by GICA cells. The mutual relationship between MG_7 antigen localization and tumor cell differetiation as well as its clinical significance were also discussed.