Localization and level of expression of beta-catenin in human laryngeal squamous cell carcinoma

OBJECTIVE: We studied the participation of beta-catenin in the histologic differentiation of laryngeal squamous cell carcinomas. STUDY DESIGN AND SETTING: At the National Institute of Respiratory Diseases, a tertiary referral center, localization and level of expression of beta-catenin were compared between normal epithelium (15 cases) and primary tumors in different degrees of differentiation (38 cases), using an immunohistochemical procedure. RESULTS: Cell membrane staining of beta-catenin was observed in normal epithelium and in well and moderately differentiated carcinomas. Cytoplasmic redistribution. was observed in poorly differentiated carcinomas. Loss of beta-catenin correlated with tumor dedifferentiation. CONCLUSION: Reduction of cell membrane beta-catenin expression correlated with tumor dedifferentiation. SIGNIFICANCE: Loss of beta-catenin may lead to diminishing the strength of the intercellular adhesion system, thereby promoting the invasive phenotype of the squamous cell carcinoma of the larynx.