Up-regulation of beta-catenin in external auditory canal cholesteatoma

Abstract

The external auditory canal cholesteatoma (EACC) is a rare disease with hyperproliferation and destructive growth in the adjacent structures. Down-regulation of beta-catenin (key component of the zonula adherens) is a pivotal factor for loose tissue integrity and invasiveness. Transforming growth factor beta1 (TGF-beta1) was reported to decrease beta-catenin in mammary epithelium. We investigated the abrogation of TGF-beta1 and beta-catenin expression in EACC culture cells. Cultured EACC-specimens were incubated with 6 micromol TGF-beta1 antisense. After 48 h, expression of beta-catenin was determined by means of immunohistochemistry. The cells showed an increased mural reactivity to beta-catenin, and intracellular reactivity was unchanged. The untreated cells showed a loss of beta-catenin expression at the membranes. The predominant membranous location after treatment with TGF-beta1 antisense suggests increased tendency of the cells for tissue formation and strong cell-cell adhesion rather than migratory and invasive character, and thus TGF-beta1 antisense application is a useful therapeutical strategy.