CK7、CK14、CK19和CK20在胃肠癌转移诊断中价值的新发掘

New diagnostic value of CK7,CK14,CK19 and CK20 expression in detecting metastases of gastrointestinal carcinoma

目的：重新评估CK7、CK14、CK19和CK20在胃肠癌淋巴结微转移中的诊断价值和意义。方法：采用组织芯片和免疫组化方法检测CK7、CK14、CK19和CK20在正常黏膜(n=112)、原发癌(n=112)、淋巴结转移癌(n=106)和肝脏转移癌(n=37)中的表达,比较它们在转移灶与原发灶间表达差异以及与临床病理参数之间的关系。结果：CK19在各种组织中的表达均为100%,原发癌和转移癌间呈一致性表达；而CK20和CK7的表达随肿瘤的发生和进展逐步下降,淋巴结转移灶中的表达水平显著低于原发癌中的表达水平(P＜0．05),CK20和CK7的下降表达与肿瘤的浸润深度有关(P＜0．05)；CK7的下降表达与肿瘤的远处转移有关(P＜0．01),胃癌中CK7的表达率高于肠癌中的表达(P=0．003),CK20正好相反(P＜0．001)。CK14在各种组织中的表达率较低,在胃肠癌的诊断中的价值不大。结论：CK19是检测胃肠癌转移的一个理想指标,而CK20和CK7在检测微转移中价值有待评估,其表达下调可能在胃肠癌发展至转移中起重要作用。

Objective：To re-evaluate the diagnostic value and clinical significance of cytokeratin 20 （CK20）, CK7, CK19, and CK14 in detecting lymph node micrometastasis of gastrointestinal carcinoma. Methods： The expression of CKT, CK14, CK19, and CK20 in normal tissues （n= 112）, primary tumors （n= 112）, lymph nodes metastases （n= 106）, and liver metastases （n=37） was detected by tissue microarray and immunohistochemical method. The results were compared between primary tumor and metastasis tumor and their correlation with clinical pathological parameters were analyzed. Results： The positive rate of CK19 was 100% in all kinds of tissues. There was no difference in CK19 expression between primary tumor and metastasis tumor. The expressions of CK20 and CK7 decreased gradually with tumor initiation and development, The expressions of CK20 and CK7 were significantly lower in metastasis tumor than those in primary tumor （P〈0.05）, The decreased expressions of CK20 and CK7 were associated with the depth of invasion （P〈0, 05） and reduced expression of CK7 was associated with distant metastasis of tumors （P〈0.01）, The expression rate of CK7 was higher in gastric carcinoma than that in colorectal carcinoma （P=0. 003）. But the expression rate of CK20 was just opposite, higher in colorectal carcinoma and lower in gastric carcinoma （P〈0. 001）. The expression rate of CK14 was lower in all kinds of tissues and had little value in diagnosis of gastrointestinal carcinoma. Conelusion：CK19 serves as an ideal marker in detecting micrometastases of gastrointestinal carcinoma. Reduced expression of CK20 and CK7 may play an important role in progression of metastasis of gastrointestinal carcinoma.