CARBOHYDRATE PROFILES OF PRIMARY BREAST CARCINOMAS AND THEIR METASTASES

Background - The considerable heterogeneity of carbohydrate expression is well documented in malignant disease. Although some studies have c ompared lectin binding patterns of primary breast tumours and local ly mph node metastases they have shown conflicting results. There is clea rly a need for further study in the assessment of the carbohydrate phe notype, as determined by lectins, to assess the significance of any di fferences observed and their implications for glycoconjugate interacti ons in metastatic tumour cell behaviour. Methods - The carbohydrate ph enotypic profiles of 36 primary breast tumours and their corresponding axillary lymph node metastases were assessed with five lectins (WGA, PNA, LTA, UEA I, and HPA) and three antisera (HMFG 2, LU-BCRU-G7, and P5252), using an immunohistochemical approach. Results - There was alm ost complete homogeneity in the phenotypic carbohydrate expression bet ween individual primary tumours and their corresponding lymph node met astases in over 79% of those cases studied. The murine monoclonal anti body LU-BCRU-G7 was the only reagent in this study which showed a majo rity of cases (59%) as having quantitative differences in reactivity b etween the primary tumour and lymph node metastasis. Conclusions - The se findings suggest that at this stage of metastasis more subtle chang es in individual glycoconjugates are responsible for subsequent metast atic cell behaviour, rather than the widespread group changes that are usually detected by lectins. The profiles observed for the fucose-bin ding lectin LTA and the anti-fucosylated glycoprotein antibody LU-BCRU -G7, further suggest that fucosylation may be a factor in metastatic c ell behaviour.