Expression of hypoxia inducible factor 1 α and Von Hippel Lindau protein in human middle ear cholesteatoma

Objective: To evaluate the role of hypoxia in cholesteatoma progression. Study Design: Immunohistochemical analysis of paraffin-embedded human specimens. Methods: Thirteen middle ear cholesteatomas and 10 samples of normal human external ear canal skin were stained immunohistochemically for the presence of hypoxia inducible factor 1 alpha (HIF 1 alpha) and Von Hippel Lindau. protein. Specimens were then analyzed semiquantitatively. Results: Staining for both antibodies could be detected in all cholesteatomas (perimatrix and matrix), as well as in the samples of normal human ear canal skin. Cholesteatoma specimens showed statistically significant increased staining when compared with normal human skin and mucosa. The age of patients and relapse surgery affected immunohistochemical staining of HIF 1 alpha and Von Hippel Lindau protein. Conclusions: Elevated staining intensities for HIF 1 alpha and Von Hippel Lindau protein in cholesteatoma tissue indicated that cholesteatoma may be bypoxic. In addition, our data indicated that relapse cholesteatomas yield a higher degree of hypoxia than ears without surgery.