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Updated: Aug 7, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Cell cycle inhibitory protein p27 in human middle ear cholesteatoma
Jerzy Kuczkowski1, Alicja Bakowska, Tadeusz Pawelczyk
1Department of Otolaryngology, Medical University of Gdansk, Gdansk, Poland. jerzyk@amg.gda.pl
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.
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