Jakab Cs, Halász J, Szász A M, Kiss A, Schaff Zs, Rusvai M, Gálfi P, Kulka J
Szent István University, Faculty of Veterinary Medicine, Department of Pathology and Forensic Veterinary Medicine, István utca 2., Budapest 1078.
J Comp Pathol. 2008 Nov;139(4):238-45. doi: 10.1016/j.jcpa.2008.08.001. Epub 2008 Oct 9.
Claudins are tight junction proteins expressed by epithelial and endothelial cells. The present study has evaluated the expression of claudin-1, -2, -3, -4, -5 and -7 in 115 hyperplastic and neoplastic lesions of the canine mammary gland and compared this expression with that of normal mammary epithelium. The lesions studied included lobular hyperplasia (n=15), simple adenoma (n=20), non-infiltrating carcinoma in situ (n=20) and infiltrating carcinomas of histological grades I, II and III (n=20 of each). There was strong expression of claudin-1, -3, -4, -5 and -7 by epithelia within examples of lobular hyperplasia and simple adenoma, and strong expression of claudin-3 and -4 by non-infiltrating carcinomas and all three grades of infiltrating carcinoma. By contrast, there was reduced expression of claudin-5 and -7 by non-infiltrating and infiltrating carcinomas and the expression of these two molecules was inversely correlated with histological grade. Claudin-1 was expressed focally within carcinoma in situ, but this molecule was not detected in any invasive carcinoma. Claudin-2 was weakly expressed within areas of lobular hyperplasia and by simple adenomas, but was not expressed by any carcinoma cells. These results suggest that loss or reduction of expression of claudin-1, -2, -5 and -7 may lead to cellular disorientation, detachment and invasion in canine mammary neoplasia.
紧密连接蛋白是由上皮细胞和内皮细胞表达的紧密连接蛋白。本研究评估了紧密连接蛋白-1、-2、-3、-4、-5和-7在115例犬乳腺增生性和肿瘤性病变中的表达，并将其与正常乳腺上皮的表达进行了比较。所研究的病变包括小叶增生（n = 15）、单纯腺瘤（n = 20）、非浸润性原位癌（n = 20）以及组织学I级、II级和III级浸润性癌（各n = 20）。小叶增生和单纯腺瘤标本中的上皮细胞强烈表达紧密连接蛋白-1、-3、-4、-5和-7，非浸润性癌和所有三级浸润性癌均强烈表达紧密连接蛋白-3和-4。相比之下，非浸润性和浸润性癌中紧密连接蛋白-5和-7的表达降低，这两种分子的表达与组织学分级呈负相关。紧密连接蛋白-1在原位癌中呈局灶性表达，但在任何浸润性癌中均未检测到该分子。紧密连接蛋白-2在小叶增生区域和单纯腺瘤中弱表达，但任何癌细胞均未表达。这些结果表明，紧密连接蛋白-1、-2、-5和-7表达的缺失或减少可能导致犬乳腺肿瘤中的细胞定向紊乱、脱离和侵袭。
