Are p53 and MIB-1 overexpressed in cholesteatoma?
INTRODUCTION: There is controversy regarding the expression of p53 and MIB-1 in cholesteatoma.1 This study was instituted to study this. p53 is an intracellular protein which plays a critical role in control of the cell cycle at the G1 check point. MIB-1 is recognized as a marker of cellular proliferation. Using deep meatal skin controls, the question addressed was, 'are p52 and MIB-1 overexpressed in cholesteatoma'? METHOD: Immunocytochemistry using the avidin-biotin technique on frozen tissue sections with primary antibody to p53 (n = 17, controls = 17) and MIB (n = 17, controls = 7) was performed on cholesteatoma and deep meatal skin control specimens. Appropriate positive and negative controls were employed for each antibody. Slides were analysed in a blind fashion by two independent observers. Statistical analysis was performed using the Mann-Whitney test. RESULTS: Expression of p53 was minimal or absent in both cholesteatoma and controls. No significant difference in p53 expression was found between the two groups (P = 0.02). MIB-1 expression was higher in cholesteatoma than in controls, although this was not statistically significant (P = 0.09). CONCLUSION: This study did not demonstrate an increased expression of p53 cholesteatoma, indicating no evidence of a dysfunctional cell cycle. MIB-1 results showed a possible trend towards significance, which requires a more powerful study to evaluate this further. The probability that there is an increased rate of cellular proliferation in cholesteatoma, when compared to deep meatal skin controls, cannot be excluded.
Motamed
M
(Departments of Otorhinolaryngology/Head and Neck Surgery and Pathology, Leicester Royal Infirmary, Leicester and Department of Clinical Laboratory Sciences, Queen's Medical Centre, Nottingham, UK).
Powe
D
Jones
L
Kendall
C
Banerjee
AR