Study of 14-3-3 sigma protein in normal and neoplastic tissues.

在正常人体组织中，14-3-3σ蛋白仅表达于各种上皮细胞中，其中以不同部位的鳞状上皮细胞免疫反应最强，其次为呼吸道基底细胞或各器官肌上皮细胞。在非小细胞肺癌中，鳞状细胞癌中14-3-3σ蛋白的表达强于腺癌。在人类结肠癌中，14-3-3σ蛋白的免疫反应性因区域或病例而异。而14-3-3σ在肿瘤侵袭前沿有阳性表达的趋势。分子生物学研究表明，该基因的甲基化不影响14-3-3σ基因在结肠癌中的表达。在乳腺癌的发生发展过程中，14-3-3σ蛋白表达下调与乳腺癌的进展密切相关。在导管癌病变中，即使在非浸润性病变中，14-3-3σ的表达也明显下调。乳腺交界性病变、柱状细胞增生伴非典型性病变表现出与导管癌病变不同的14-3-3σ表达模式，提示为乳腺癌前病变。

In normal human tissues, 14-3-3 σ protein was exclusively present in various epithelial cells, of which squamous epithelia at various sites showed the strongest immunoreactivity and basal cells of respiratory tract or myoepithelial cells of various organs followed. In non-small cell carcinoma of the lung, squamous cell carcinoma expressed stronger immunoreactivity for 14-3-3 σ protein than adenocarcinoma. In human colon cancers, immunoreactivity for 14-3-3 σ protein varied from area to area or case to case. However, there was a tendency to be positive for 14-3-3 σ expression at tumor invasion front. Molecular biological study revealed that DNA methylation of the gene did not influence the expression of the 14-3-3 σ gene in colon cancers. In breast carcinogenesis, down-regulation of 14-3-3 σ protein was well correlated with its progression. In ductal carcinoma lesions, even in non-invasive, marked down-regulation of 14-3-3 σ expression was observed. Breast borderline lesion, columnar cell hyperplasia with atypia showed different 14-3-3 σ expression pattern from that of ductal cancer lesion, suggesting it to be precancerous lesion of the breast.