A STUDY OF DESMOSOMES IN COLORECTAL-CARCINOMA
A STUDY OF DESMOSOMES IN COLORECTAL-CARCINOMA
复制标题
DOI：
10.1038/bjc.1990.382
复制
发表时间：
1990-11-01
影响因子：
8.8
通讯作者：
GARROD, DR
中科院分区：
文献类型：
--
作者：
COLLINS, JE;TAYLOR, I;GARROD, DR
桥粒是上皮细胞的粘附连接。它们的表达可能在癌中改变或丢失，导致细胞凋亡减少。应用荧光抗体染色、免疫印迹和电镜技术对结直肠癌桥粒进行了研究。一系列的58个恶性标本，包括原发肿瘤和转移，桥粒阳性。没有迹象表明桥粒表达的相对减少可能会导致肿瘤细胞凋亡减少，尽管在低分化肿瘤中极化连接分布的丧失可能会产生这样的后果。结直肠癌和培养的癌细胞的蛋白质印迹分析鉴定了桥粒多肽dp1 + 2，dg1和dg2 + 3，它们与正常同源物具有相似的相对分子量。此外，抗dg 2 + 3抗血清仅在恶性上皮中识别出140，000的多肽。这种多肽的意义尚不清楚。将肿瘤和未受累的上皮细胞暴露于低细胞外[Ca2+]，以测试肿瘤桥粒是否具有降低的稳定性。这导致了肿瘤细胞的大量降解，但一些活细胞团块具有抗低[Ca2+]破坏的桥粒。因此，桥粒可能通过维持转移细胞之间的细胞间粘附而在转移中起积极作用。
Desmosomes are adhesive junctions of epithelial cells. Their expression may be altered or lost in carcinomas resulting in reduced cellular adhesiveness. The desmosomes of colorectal carcinomas have been studied by fluorescent antibody staining, immunoblotting and electromicroscopy. A series of 58 malignant specimens, comprised of primary tumours and metastases, were desmosome positive. There was no indication of a comparative reduction in desmosome expression that might give rise to reduced adhesiveness of tumour cells, although loss of polarised junctional distribution in poorly differentiated tumours might have such a consequence. Western blotting analysis of colorectal cancers and cultured carcinoma cells identified desmosomal polypeptides dp1 + 2, dg1 and dg2 + 3 with similar relative molecular weights to normal homologues. In addition, a polypeptide of 140,000 was recognised only in malignant epithelium by anti-dg2 + 3 antiserum. The significance of this polypeptide is not understood. Tumours and uninvolved epithelium were exposed to low extracellular [Ca2+] to test whether tumour desmosomes were of reduced stability. This caused much cellular degradation in tumours but some viable cell clumps possessed desmosomes resistant to disruption by low [Ca2+]. Desmosomes may thus have a positive role in metastasis by maintaining intercellular adhesion between metastasising cells.