Cell-Molecular Biological Study on Detectin of Occult Metastatic Lesions in Lung Cancer

为发现无血行远处转移的非小细胞肺癌的隐匿性转移灶，应用抗细胞角蛋白18（CK18）单克隆抗体，对非小细胞肺癌骨髓穿刺标本进行了CK18免疫细胞化学检测。CK18阳性细胞在非小细胞肺癌中的检出率为53（Ⅰ期32.3%，Ⅲ期63.6%，Ⅳ期100%）。α_2，α_3，α_5，α_6，整合素亚基的表达频率较高。α_2整合素亚基阳性组的细胞角蛋白18阳性细胞检出率明显高于α_2整合素亚基阴性组。整合素α_6 β_4亚基与Catepsin B在肺癌组织中的表达呈高度相关性，整合素作为细胞粘附分子在肺癌隐匿性转移灶的形成中起重要作用，尤其是α_2 β_1亚基在非小细胞癌中可能参与原发灶的转移释放、向血流的迁移和隐匿性转移的形成。

In order to detect occult metastatic lesions in non-small cell lung cancer without clinically hematogenous distant metastasis, cytokeratin positive cell in bone marrow aspirates were analyzed by immunocytochemical method using monoclonal antibody to cytokeratin 18.Cytokeratin 18 positive cells were detected in 34/64 (53%) among non-small cell carcinoma (Stage I 32.3%, III 63.6%, IV 100%).The alpha_2, alpha_3, alpha_5, alpha_6, integrin subunits were frequently expressed. The detection rate of cytokeratin 18-positive cells of alpha_2 integrin subunitt positive lung cancer was significantly higher than that of the alpha_2 subunit negative group. A highly significant correlation was revealed between the alpha_6beta_4 integrin subunitt and the expression of Catepsin B in lung cancer,Integrins play very important roles as cellular adhesion molecules in occult metastatic lesion formation of lung cancer.Especially ; alpha_2beta_1 integrin subunit may contribute to metastatic release from a primary site, migration into bloodstream and occult matastatisis formation in non-small cell carcinoma.