Kim J C, Gong G, Roh S A, Park K C
Department of Surgery, University of Ulsan College of Medicine and Asan Institute for Life Sciences, Seoul, Korea.
Mol Cells. 1999 Apr 30;9(2):133-7.
The presence of the carcinoembryonic antigen (CEA) gene and CEA expression in the liver was tested to identify their possible roles in the liver metastasis of colorectal carcinoma. The CEA gene in the liver was identified by amplifying the CEA-specific N-terminal domain exon with digoxigenin-dUTP labeling in 16 colorectal carcinomas with liver metastases. Next, CEA expression was tested by immunostaining using the anti-CEA monoclonal antibody (T84.66, ATCC). Liver tissues from 13 stomach cancer patients and 12 colorectal cancer patients without liver metastasis were also tested as control groups. Three grades (<25%, 25-50%, and 50%< or =) were given according to the proportion of positive cells. The CEA gene was amplified in the metastatic tumor cells of the liver (2.6 +/- 0.2, mean grade +/- SEM) and their surrounding hepatocytes (1.5 +/- 0.2) in all cases. CEA expression was found in all metastatic tumor cells and 14 cases of the surrounding hepatocytes. Among the control groups, the CEA gene of the hepatocytes was found in 9 cases each of the colorectal and the stomach cancers that did not exhibit CEA expression. The level of serum CEA was related with the numbers and volume of liver metastases, but not with CEA expression in tumor cells and surrounding hepatocytes. The CEA gene in the metastatic tumor cells, not in the hepatocytes, was closely associated with CEA expression in the surrounding hepatocytes (p<0.01). Although the precise mechanism of CEA gene regulation in hepatocytes remains to be proven, the CEA gene in the metastatic tumor of the liver seems to affect CEA expression in the surrounding hepatocytes facilitating liver metastasis in colorectal carcinoma.
检测癌胚抗原（CEA）基因的存在及肝脏中CEA的表达，以确定它们在结直肠癌肝转移中可能发挥的作用。通过用地高辛配基-dUTP标记扩增CEA特异性N端结构域外显子，在16例伴有肝转移的结直肠癌中鉴定肝脏中的CEA基因。接下来，使用抗CEA单克隆抗体（T84.66，美国典型培养物保藏中心）通过免疫染色检测CEA表达。还检测了13例胃癌患者和12例无肝转移的结直肠癌患者的肝组织作为对照组。根据阳性细胞比例给出三个等级（<25%、25 - 50%和50%<或=）。在所有病例中，肝脏转移瘤细胞（2.6 +/- 0.2，平均等级+/-标准误）及其周围肝细胞（1.5 +/- 0.2）中均扩增出CEA基因。在所有转移瘤细胞和14例周围肝细胞中发现了CEA表达。在对照组中，在未表现出CEA表达的结直肠癌和胃癌各9例中发现了肝细胞的CEA基因。血清CEA水平与肝转移的数量和体积有关，但与肿瘤细胞及周围肝细胞中的CEA表达无关。转移瘤细胞而非肝细胞中的CEA基因与周围肝细胞中的CEA表达密切相关（p<0.01）。虽然肝细胞中CEA基因调控的确切机制仍有待证实，但肝脏转移瘤中的CEA基因似乎会影响周围肝细胞中的CEA表达，从而促进结直肠癌的肝转移。
