EFFECT OF SNUFF ON CYTOKERATIN EXPRESSION IN ORAL VESTIBULAR SULCUS EPITHELIUM

Differences in the expression of cytokeratins (CK) in specimens obtain ed from snuff-affected oral epithelium of the maxillary vestibular sul cus and clinically normal sulcular epithelium were studied by indirect immunofluorescence staining with a panel of monoclonal antibodies (MA bs). CK 14, a marker of stratified squamous epithelium, was not seen e xpressed in 3/11 of the snuff user's specimens. Terminal differentiati on markers, typical of cornified epithelia (CK 1, 9, 10 and 11), mere detected suprabasally in the snuff user's keratosis but not in the nor mal control epithelium. The use of snuff seemed to change the CK stain ing pattern of the mucosa so that it resembles more that of a cornifie d type of epithelium. Simple epithelial-type CK were included in the s tudy in order to establish the CK profile of the snuff-induced keratos is, for comparison with normal and dysplastic lesions. MAb to CK 7 and 19 showed reactivity in the basal cells and suprabasally, whereas the monospecific MAb anti-CK 7 showed suprabasal staining both in the con trol and affected epithelia. By using MAbs, we found no immunoreactivi ty against CK. 18 either in normal or affected epithelia, whereas we f ound suprabasal reaction (5/11) against CK 8 in the snuff user's epith elia. The two MAbs demonstrating the expression of CK 19, normally con fined to the basal cells of the stratified squamous epithelium, showed variable patterns of expression both in basal cells and suprabasally in the snuff lesions. The results show that use of oral snuff causes s ome alterations in the CK expression pattern of the affected epitheliu m. Whether the alterations are indicative of a premalignant change is, however, uncertain, The results encourage further studies on the subj ect.