中耳胆脂瘤组织中碳酸酐酶的免疫组化研究

目的:探讨碳酸酐酶(carbonic anhydrase,CA)在中耳胆脂瘤组织中的表达及其在中耳胆脂瘤骨质破坏机制中的作用.方法:采用免疫组化SABC染色法检测54例(57耳)中耳胆脂瘤和22例正常外耳道皮肤中CA的表达.结果:CA在中耳胆脂瘤上皮和正常外耳道皮肤的阳性表达率分别为98.25%和63.64%,中耳胆脂瘤组织CA的表达较正常外耳道皮肤高(P＜0.05).CA在胆脂瘤上皮各层细胞均有阳性表达,角化物为阴性表达.正常外耳道皮肤CA主要分布在棘细胞层和颗粒层,基底细胞层和角质层表达较弱.广泛性胆脂瘤和局限性胆脂瘤CA表达差异无统计学意义(P＞0.05).结论:CA在中耳胆脂瘤组织中的表达增强,可能与胆脂瘤破坏骨质的脱矿物质阶段有关.

A IMMUNOHISTOCHEMICAL STUDY ON CARBONIC ANHYDRASE IN MIDDLE EAR CHOLESTEATOMA

Objective:To explore the expression of carbonic anhydrase(CA) in middle ear cholesteatoma and the roles in the mechanisms of bone resorption associated with cholesteatoma.Methods:Specimens from 54 cases(57 ears) of middle ear cholesteatoma and 22 cases of external ear skin were examined by immunohistochemical SABC method for CA.Result:The rates of positive signal were 98.25% and 63.64% in cholesteatoma and in external ear skin,respectively.CA was expressed in cytoplasm and in cytoblast.Expression of CA was in all layers of the epithelium in cholesteatoma and in external ear skin,but Cholesteatoma showed a significantly stronger expression of CA than external ear skin(P<0.05).The antibody for CA displayed positive staining in all layers of epidermis in cholesteatoma,and revealed a positive staining in the stromal cell and granular cell layers in external ear skin,but weak in the basal cell and the stratum corneum.Expression of CA did not showed a significant difference between extensive cholesteatoma and localized cholesteatoma(P>0.05).Conclusion:Expression of CA in middle ear cholesteatoma was higher than external ear skin,and CA seemed to participate in the bone erosion associated with cholesteatoma at the stage of demineralization.