ADHESION MOLECULE PROFILE AND MALIGNANCY OF MELANOCYTIC LESIONS

The ability of melanoma cells to metastasize is largely dependent upon cell surface molecules that mediate cell-matrix and cell-cell interac tions. Our aim was to investigate the expression of such molecules (ad hesion molecules) on tissue sections of a series of melanocytic lesion s in different stages of tumour progression. Four common naevi, four c ongenital naevi, four dysplastic naevi, three Spitz naevi, 20 primary melanomas and 15 metastatic melanomas were tested with an alkaline pho sphatase/anti-alkaline phosphatase technique and a panel of monoclonal antibodies directed toward different alpha subunits of VLA receptors, beta1, VNR-alpha and beta3 subunit, and CD44 hyaluronate receptor. On ly metastatic melanomas expressed the alpha4 subunit, and only thick p rimary melanomas and metastases expressed the beta3 subunit. The alpha 6/beta1 chain was expressed at significantly higher levels on benign l esions, and a trend towards increased expression of alpha2 and alpha3 subunits was found in malignant versus benign lesions. Our results sho w that the pattern of integrin expression changes in melanocytic lesio ns along with malignant transformation.