Cell cycle inhibitory protein p27 in human middle ear cholesteatoma

Aim: To evaluate the immunohistochemical and molecular presentation of protein p27 in cholesteatoma. Methods: 42 cholesteatoma samples and 6 external ear canal skin (EECS) specimens were investigated and analyzed taking into consideration congenital, acquired, recurrent cholesteatoma, and EECS. Results: The expression of p27 was found in 16 (38.1%) out of 42 specimens of cholesteatoma and in 5 (83.3%) out of 6 specimens of EECS. There was a significant difference in p27-positive staining rate between EECS and cholesteatoma epithelium (p < 0.008). The presence of p27 was detected in 10 cases of acquired cholesteatoma, 2 cases of congenital and 3 cases of recurrent cholesteatoma. There was no significant difference between the presence of p27 in cholesteatoma and EECS (p = 0.01). Conclusion:The down-regulation of p27 is a key player in cell cycle control and plays an undefined role in the pathogenesis of all types of cholesteatoma. Copyright (c) 2006 S. Karger AG, Basel