Korean J Otolaryngol-Head Neck Surg.  1997 Jul;40(7):984-989.

Expression of PLC- 1 in Human Middle Ear Cholesteatoma

• Chun YM
• Park KH
• Lee DH
• Hwang SC

Abstract

BACKGROUND: EGF and TGF-gamma are believed to mediate their pleiotrophic actions by binding to and activating cell surface receptors with an intrinsic protein-tyrosine kinase. Protein-tyrosine kinase phosphorylation has been considered involved in intrinsic signal transduction, proliferation and transformation of the cells. Phospholipase C-gamma1 is well characterized substrate for tyrosine kinase.
OBJECTIVE
The purpose of this study is to elucidate the distribution of PLC-gamma1 in normal meatal skin and cholesteatoma matrix.
MATERIALS AND METHODS
8 cholesteatoma specimens were obtained from operated patients for immunohistochemistry and western blot analysis.
RESULTS
On immunohistochemistry, PLC-gamma1 was detected only in basal layer of the deep meatal skin, but was readily detectable in both the basal and suprabasal layer in cholesteatoma matrix. By western blot analysis, considerable higher levels of PLC-gamma1 protein were detectable in cholesteatoma matrix compared with the deep meatal skin.
CONCLUSION
Overexpression of PLC-gamma1 in cholesteatoma suggests a possible derangement of enhanced growth signal transduction in keratinocytes.

Keyword

Cholesteatoma; Phospholipase C-gamma1; Signal transduction

MeSH Terms

Blotting, Western
Cholesteatoma
Cholesteatoma, Middle Ear*
Ear, Middle*
Epidermal Growth Factor
Humans*
Immunohistochemistry
Keratinocytes
Phospholipases
Phosphorylation
Protein-Tyrosine Kinases
Receptors, Cell Surface
Signal Transduction
Skin
Epidermal Growth Factor
Phospholipases
Protein-Tyrosine Kinases
Receptors, Cell Surface