中耳胆脂瘤组织中的Ras蛋白的表达及病理意义

The expressive activity of Ras Protein in the epithelia of human middle ear cholesteatoma and its implication in the pathogenesis of the lesion

目的观察Ras蛋白在继发性中耳胆脂瘤组织中的表达活性及其病理意义。方法32例胆脂瘤上皮标本和12例正常面部表皮标本,免疫组织化学法(SP法)分别检测Ras蛋白表达水平,并应用HPIAL-2000高分辨图象分析系统进行半定量分析,比较不同组织中的Ras活性表达差异。结果Ras蛋白的免疫阳性染色物呈棕黄色颗粒。在胆脂瘤上皮细胞,阳性反应物位于胞膜者28例(28/32);同时位于胞膜、胞浆者2例(2/32);仅存在于胞浆者2例(2/32)。在正常表皮细胞,阳性反应物主要位于胞膜,以基底层细胞着色为主。两组的阳性反应物平均吸光度(A值)分别为0.826和0.438,组间差异具有统计学意义(P<0.001)。结论继发性中耳胆脂瘤上皮组织中Ras蛋白的表达活性明显升高,提示胆脂瘤上皮具有高度的增殖活性。

Objective To investigate the expressive activity of Ras protein in the epithelia of secondary human middle ear cholesteatoma and its implication in the pathogenesis of the lesion based on trial carried out in a group of clinical samples. Methods Included in this study were 32 epithelial samples of human middle ear cholesteatoma, with 12 facial skin samples of healthy human as controls. Immunohistochemical SP procedures were taken to detect the expressive activity of Ras protein in these samples, with HPIAL-2000 high resolution image-conduct system to do a semi-quantitative analysis through determining the optical density of positive ceils in the tissue samples to make a comparison on the difference between these different samples. Results The positively stained protein was shown in the epithelia of cholesteatoma as brown-yellow granule, with such positive granule seen in cellular membrane in 28 samples （28/32）, seen in cytoplasm in 2 samples （2/32） and simultaneously seen in both of cellular membrane and cytoplasm in 2 ones （2/32）, while they were seen located mainly in the cellular membrane of healthy facial skin samples, especially in that of basilar layer of skin. The averaged optical density （A value） of positive Ras protein was 0.826 for cholesteatoma while it was 0.438 for skin, with a very significant difference between these two groups of samples （P〈0.001）. Conclusions The expressive activity of Ras protein is significantly increased in the epithelia of secondary human middle ear cholesteatoma and it may suggest that much higher proliferating activity should be brought about in cholesteatoma epithelia.