Nozawa Y, Van Belzen N, Van der Made A C, Dinjens W N, Bosman F T
Department of Pathology, Erasmus University Rotterdam, The Netherlands.
J Pathol. 1996 Jan;178(1):48-52. doi: 10.1002/(SICI)1096-9896(199601)178:1<48::AID-PATH432>3.0.CO;2-Y.
Nucleophosmin/B23 is a 38 kD molecular phosphoprotein involved in ribosome assembly and transport. In view of the fact that nucleophosmin/B23 appears to be more abundant in tumour cells than in normal cells, the mRNA expression and immunohistochemical localization of nucleophosmin/B23 were investigated in 19 samples of non-neoplastic mucosa, six adenomas, and 16 adenocarcinomas of the colorectum. Northern blot analysis revealed that nucleophosmin/B23 mRNA is expressed at a higher level in adenomas and carcinomas than in non-neoplastic mucosa of the colorectum. Immunohistochemical staining of formalin-fixed, paraffin-embedded tissue sections after microwave antigen retrieval, using a nucleophosmin/B23-specific monoclonal antibody, showed almost exclusively diffuse nuclear reactivity of a majority of the epithelial cells in non-neoplastic mucosa: in adenomas, reactivity was almost exclusively nucleolar and in carcinomas, nuclear as well as nucleolar staining was observed. During mitosis, the immunoreactivity of nucleophosmin/B23 appears in the cytoplasm. The results indicate that the expression of nucleophosmin/B23 is higher in neoplastic than in non-neoplastic colorectal mucosa. Furthermore, the pattern of nucleophosmin/B23 expression shifts from nuclear to nucleolar early in the adenoma-carcinoma sequence. The exact function of nucleophosmin/B23 in colorectal carcinogenesis remains to be determined.
核磷蛋白/B23是一种38kD的分子磷蛋白，参与核糖体的组装和运输。鉴于核磷蛋白/B23在肿瘤细胞中似乎比在正常细胞中更为丰富，我们对19份非肿瘤性大肠黏膜样本、6份腺瘤样本以及16份大肠腺癌样本进行了核磷蛋白/B23的mRNA表达及免疫组化定位研究。Northern印迹分析显示，核磷蛋白/B23的mRNA在腺瘤和癌组织中的表达水平高于大肠非肿瘤性黏膜。使用核磷蛋白/B23特异性单克隆抗体，对经微波抗原修复处理的福尔马林固定、石蜡包埋组织切片进行免疫组化染色，结果显示，在非肿瘤性黏膜中，大多数上皮细胞几乎仅呈现弥漫性核反应；在腺瘤中，反应几乎仅见于核仁；而在癌组织中，则观察到核及核仁染色。在有丝分裂期间，核磷蛋白/B23的免疫反应出现在细胞质中。结果表明，核磷蛋白/B23在肿瘤性大肠黏膜中的表达高于非肿瘤性黏膜。此外，在腺瘤-癌序列的早期，核磷蛋白/B23的表达模式从核内转变为核仁内。核磷蛋白/B23在大肠癌变的确切功能仍有待确定。
