MUC1 mucin and carbohydrate associated antigens as tumor markers in head and neck squamous cell carcinoma

Abstract

An immunological analysis to study MUC1 mucin core protein and carbohydrate associated antigens as tissue tumor markers in head and neck carcinoma was performed. Twenty nine patients with the following tumor localizations were included: tongue (n=10), larynx (n=8), oral cavity (n=4), maxillary sinus (n=3), tonsillar ring (n=3) and pharynx (n=1); seven samples of epithelium obtained from normal organs at the same localizations were studied as controls. Immunohistochemical analysis was performed following standard procedures and reaction was graded according to staining intensity and distribution. From each tissue section, membrane, cytoplasmic and nuclear moieties were obtained by differential centrifugation with subsequent fractionation by density gradient centrifugation (6M guanidium chloride-CsCl); subcellular moieties and CsCl derived fractions were analyzed by immunoblotting. Monoclonal antibodies (MAbs) reacting with the core protein of MUCI (C595) and associated carbohydrate antigens were: Tn, 83D4 MAb; Lewis y antigen (Le y), C14 MAb; Lewis x antigen (Le x), KM380 MAb and sialyl Lewis x (sLe x), KM93 MAb. Statistical analysis was undertaken by Spearman rank correlation. In tumor samples, the immunohistochemical identification of MUCl core protein and associated antigens was extended; differences were found in the pattern and intensity of expression; results were corroborated by immunoblotting although in a few samples there was not coincidence between both methods. Localization, tumor mass or node involvement did not show significant differences for any of the antigens studied. 1) head and neck carcinoma expressed MUCI and associated carbohydrate antigens in high levels; 2) no relationship between antigenic expression and tumor status was found.