Changes of Apoptosis according to the Site and Clinical Stage of Experimental Cholesteatoma / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Aural cholesteatoma is a destructive disease of the middle ear caused by progressive expansion of keratinizing squamous epithelium. Previous studies reported that apoptosis of keratinizing squamous epithelium was increased in cholesteatoma which involves various genes in the regulation process. In the present study, we investigated the degree of apoptosis using expression of bcl-2, p53 and bax in various sites of experimental cholesteatomas. We also investigated the degree of apoptosis in different clinical stages of cholesteatoma. MATERIALS AND METHOD: Using canal ligation cholesteatoma in mongolian gerbil, we performed immunohistochemical stainings of bcl-2, p53 and bax. Labeling indices of bcl-2 and p53 expressoin and subjective grading of bax expression were measured and analyzed according to the site and clinical stage of cholesteatoma. RESULTS: 1) Expression of bcl-2 and p53 were significantly increased at lateral external auditory canal compared with those at the tympanic membrane. 2) Expression of bax of cholesteatoma was significantly increased compared with that of the normal external auditory canal. 3) Expression of bcl-2 and bax were significantly increased in the stage I and expression of p53 was increased in the stage III of cholesteatoma. CONCLUSION: Changes of bcl-2, p53 and bax expression in experimental cholesteatoma may be related with various apoptosis according to the different sites and different clinical stages of cholesteatoma.