Expression of the extracellular matrix protein tenascin in laryngeal epithelial lesions: correlation with fibronectin, CD44, cathepsin D and proliferation indices

Tenascin (TN) is an extracellular matrix glycoprotein expressed in areas of epithelial-mesenchymal interactions during embryogenesis and in neoplasia. We studied the expression of TN in a series of 35 squamous cell invasive carcinomas of the larynx, 13 in situ carcinomas, 41 cases of dysplasia, 10 papillomas and 18 cases of keratosis using the monoclonal antibody TN2 on paraffin-embedded tissue. TN expression was correlated with the expression of fibronectin, CD44 and cathepsin D (CD) proteins, with the proliferation indices Ki-67 and proliferating cell nuclear antigen (PCNA) as well as with conventional clinicopathological variables. Malignant tumours showed a significantly greater stromal TN staining than benign lesions. In invasive carcinomas, the immunoreactivity was statistically higher than that in situ (P=0.01), dysplastic lesions (P