S-100 PROTEIN REMAINS A PRACTICAL MARKER FOR MELANOCYTIC AND OTHER TUMORS

S-100 protein, extracted from bovine brain, is the first described of the modern generation of marker molecules for melanocytic tumours. Des pite the observation thal many different types of cells express S-100 protein, detection of the molecule in tumour cells in appropriate clin ical and pathological circumstances is a widely used and effective adj unct to the determination that a tumour is melanocytic. Antibodies to S-100 protein are best deployed as part of a package that includes ant ibodies to other melanoma-associated epitopes (HMB-45, NKI-C3/Beteb), cytokeratins and common leukocyte antigen. Antibodies to S-100 protein may also increase the accuracy of melanoma staging and permit detecti on of small numbers of metastatic tumour cells that are not detectable by conventional histology. Future applications will probably include the wider use of antibodies to the S-100 protein monomers (alpha and b eta) and the detection and quantification of S-100 protein in body flu ids and tissues.