Expression of hypoxia inducible factor 1 alpha 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 hypoxic. In addition, our data indicated that relapse cholesteatomas yield a higher degree of hypoxia than ears without surgery.