Utsunomiya Takashi, Yao Takashi, Tamiya Sadafumi, Tsuneyoshi Masazumi
Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Pathol Res Pract. 2002;198(2):69-76. doi: 10.1078/0344-0338-00189.
Intermediate filaments are known as cytoskeletal elements. Recently, additional vimentin expression has been reported in some carcinomas; however, the function of such expression remains unclear. We studied the intracellular distribution of low-molecular weight cytokeratin and vimentin by immunohistochemistry in 17 vimentin-positive gastric carcinomas using confocal laser scanning microscopy. All materials were formalin-fixed and paraffin-embedded. Low-molecular weight cytokeratin expression showed a membranous pattern with a prominent deposition just below the cytoplasmic membrane in both tubular and solid components of the carcinomas. This unique membranous deposition was frequently absent in diffuse components. On the other hand, vimentin expression showed a fibrillary pattern in all components and also showed a unique basal distribution in the tubular components. We also recognized an aggregate pattern of the intermediate filament expression in diffuse components. We conclude that the significance of vimentin expression in carcinoma cells cannot be explained as a simple substitution for low-molecular weight cytokeratin because the distribution of vimentin and low-molecular weight cytokeratin is different.
中间丝被认为是细胞骨架成分。最近，有报道称在一些癌组织中出现了额外的波形蛋白表达；然而，这种表达的功能仍不清楚。我们使用共聚焦激光扫描显微镜，通过免疫组织化学研究了17例波形蛋白阳性胃癌中低分子量细胞角蛋白和波形蛋白的细胞内分布。所有材料均经福尔马林固定和石蜡包埋。低分子量细胞角蛋白表达呈膜状模式，在癌组织的管状和实体成分中，细胞质膜下方有明显沉积。这种独特的膜状沉积在弥漫成分中常不存在。另一方面，波形蛋白表达在所有成分中呈纤维状模式，在管状成分中还呈现独特的基底分布。我们还在弥漫成分中识别出中间丝表达的聚集模式。我们得出结论，癌细胞中波形蛋白表达的意义不能简单地解释为对低分子量细胞角蛋白的替代，因为波形蛋白和低分子量细胞角蛋白的分布不同。
