CYTOPLASMIC ACCUMULATION OF ALPHA-CATENIN IS ASSOCIATED WITH AGGRESSIVE FEATURES IN LARYNGEAL SQUAMOUS-CELL CARCINOMA

Aberrations in the function of alpha-catenin (alpha-cat), the anchorin g protein of E-cadherin, are believed to cause dysfunction of the cadh erin-catenin complex, leading to disturbed cell-cell adhesion. It has been suggested that expression of alpha-cat in human tumours might be a better indicator of aggressive phenotype than expression of E-cadher in. The value of alpha-cat as a prognostic marker in laryngeal squamou s cell carcinoma (LSCC) is unclear. To determine the potential prognos tic significance of alpha-cat, paraffin-embedded samples from 159 pati ents with invasive carcinoma left in the section and with long-term fo llow-up were evaluated immuno-histochemically for alpha-cat expression , and the results were related to histopathological grade, tumour stag e and survival. Two patterns of staining were observed: pure membranou s staining (57%) and membranous staining with cytoplasmic involvement (43%). Cytoplasmic involvement of alpha-cat was associated with dediff erentiation, advanced tumour stage and nodal status. In addition, supr a-glottic tumours showed more often cytoplasmic involvement of alpha-c at than glottic tumours. Patients with cytoplasmic involvement appeare d to have a trend towards poor overall survival, though without statis tical significance. These results suggest that cytoplasmic involvement of alpha-cat is associated with aggressive behaviour and metastatic p henotype of LSCC. Int. J. Cancer (Pred. Oncol.) 79:546-550, 1998. (C) 1998 Wiley-Liss, Inc.