Franke W W, Nuber U A, Schmidt A, Schäfer S
Division of Cell Biology, German Cancer Research Center, Heidelberg.
Verh Dtsch Ges Pathol. 1994;78:8-14.
The cells of most normal and malignantly growing tissues are connected by "adhering junctions", i.e. distinct sites of "homotypic" contact between the plasma membranes of two cells of the same or a similar kind, associated on the cytoplasmic side by a dense plaque at which often bundles of cytoskeletal filaments anchor. Of the various types of adhering junctions desmosomes are characteristic of epithelia and carcinomas but also occur in some other cell types. Their molecular components have recently been identified and characterized by cDNA-cloning and sequencing. Unexpectedly, the molecular complement of desmosomes has been found to show certain differences in different epithelia, with particularly complex patterns in stratified squamous epithelia as well as in tumors and cultured cell lines derived therefrom. In addition, molecular principles important in the assembly of desmosomes and in the specific anchorage of intermediate-sized filaments (IFs) at desmosomal plaques have been elucidated. The possible value of cell type-specific isoforms of desmosomal components as markers for the subtyping of carcinomas and the role of desmosomal cadherins during invasion and metastasis of carcinomas are discussed.
大多数正常组织和恶性生长组织的细胞通过“黏附连接”相连，即相同或相似类型的两个细胞的质膜之间“同型”接触的特定部位，在细胞质一侧与一个致密斑相关联，细胞骨架细丝束常常在此处锚定。在各种类型的黏附连接中，桥粒是上皮细胞和癌组织的特征，但也存在于其他一些细胞类型中。它们的分子成分最近已通过cDNA克隆和测序得以鉴定和表征。出乎意料的是，已发现桥粒的分子组成在不同上皮细胞中存在某些差异，在复层鳞状上皮以及由此衍生的肿瘤和培养细胞系中表现出特别复杂的模式。此外，已阐明了在桥粒组装以及中等大小细丝（IFs）在桥粒斑处的特异性锚定中重要的分子原理。还讨论了桥粒成分的细胞类型特异性同工型作为癌组织亚型标志物的可能价值以及桥粒钙黏蛋白在癌组织侵袭和转移过程中的作用。
