INCREASED EXPRESSION OF A 38KD CELL-SURFACE GLYCOPROTEIN MH99 (KS-1 4) IN ORAL MUCOSAL DYSPLASIAS/

A ''window of expression'' of a 38-kD cell-surface glycoprotein MH99 ( KS 1/4 antigen) has been observed in dysplastic oral tissues using an MH99-specific monoclonal antibody. It appeared that expression of this epitope increases from baseline levels in normal oral epithelium to t hat of high levels in mild, moderate and severe dysplasia. In invasive squamous cell carcinoma, relatively low levels of expression were obs erved. In contrast? high levels of expression were demonstrated in bas al cell carcinomas. Antibody reactivity could clearly distinguish betw een the margins of histologically normal and dysplastic tissues. It is envisaged that the expression of this cell-surface glycoprotein, whic h is possibly related to nidogen, a matrix-adhesion molecule with rece ptor-like function, could be used in monitoring progression or regress ion of these lesions and assessment of surgical excision margins. It c ould also be useful in in vivo and in vitro investigations into molecu lar changes underlying the formation of dysplastic lesions.