Overexpression of placenta growth factor in human middle ear cholesteatoma

Conclusions. The expression and localization of placenta growth factor ( PlGF) within cholesteatoma were defined. The authors propose that PlGF is an angiogenic growth factor in cholesteatoma, and participates in the neoangiogenesis of cholesteatoma. Objectives. Middle ear cholesteatoma is characterized by the presence of a keratinizing squamous epithelium with hyperproliferative features. Such growth can only be supported by abundant blood vessels. Because proliferating tissues require an enhanced blood supply, angiogenesis appears to be a prerequisite for the expansion of cholesteatoma. This study aimed to analyze the presence of PlGF as an angiogenic growth factor in human cholesteatoma. Materials and methods. Tissue samples from human cholesteatoma and normal auditory meatal skin were obtained from patients during surgery for cholesteatoma of the middle ear. PlGF mRNA expression was quantified by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). PlGF was localized by immunohistochemical staining. Western blotting was used for detection of PlGF protein. Results. Expression of PlGF mRNA was significantly elevated in the epithelium of cholesteatoma compared with normal auditory meatal skin. PlGF was detected on cholesteatoma by Western blotting. PlGF was detected in the suprabasal layer of cholesteatoma using immunohistochemical study, but was not detected in normal auditory meatal skin.