Expression of Ki-67 and Topoisomerase IIa in Human Middle Ear Cholesteatoma Epithelium / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Cholesteatoma is a destructive lesion of the middle ear or mastoid process. The development of human cholesteatoma is due to the altered control of cellular proliferation in part, which tilts the balance toward the aggressive, invasive growth of squamous epithelium within the middle ear. Many efforts were performed to prove overproliferative characteristics of cholesteatoma using various proliferation markers. Nonetheless, trigger site of overproliferation within the overgrowing epithelium of cholesteatoma is still ill defined. MATERIALS AND METHODS: In this study, we used the monoclonal antibody Ki-67 and Topoisomerase II, a marker of active proliferation, on frozen sections obtained from 12 cholesteatoma samples and observed expression of these markers in three different regions, from normal meatal skin, transitional zone and cholesteatoma sac. RESULTS: The results were interpreted on the basis of nuclear staining and percentage of positively stained cells (labeling index). We found that labeling indices of cholesteatoma and transitional zone were significantly increased compared with that of normal meatal skin. CONCLUSION: This result suggested that initiating of overproliliferation of cholesteatoma epithelium started from the transitional zone.