Differential lectin-bindings in normal and precancerous epithelium and squamous cell carcinoma of the oral mucosa.

In order to establish a useful and objective marker of malignancy of oral mucosa, the binding sites for Ulex europaeus agglutinin I (UEA-I). Bandeiraea simplicifolia agglutinin I (BSA-I) and peanut agglutinin (PNA) were comparatively examined in the surgical materials from the normal, dysplastic and cancerous epithelium of the oral mucosa by a novel lectin-antilectin immunoperoxidase method. Based on the staining patterns of the normal keratinized epithelium, UEA-I was regarded as the marker for the prickle cells, BSA-I for the cells in the upper prickle to the horny layers, and PNA for those in the basal layer. As the degree of dysplasia advanced, all layers of epithelium came to react with UEA-I and PNA, whereas the BSA-I binding was negative. Positive reactions for UEA-I and PNA were seen in most carcinoma cells other than the keratinizing foci stained by BSA-I. The results indicate that a UEA-I-positive reaction in the basal cells, a PNA-positive in the prickle cells and loss of receptor for BSA-I occur in the course of malignant transformation of oral mucosa, and that these lectins may be regarded as useful markers of oral epithelial cytoplasmic differentiation.