DETECTION OF ENDOGENOUS RECEPTORS FOR CARBOHYDRATE LIGANDS IN PRIMARYAND METASTATIC HUMAN RENAL-CELL CARCINOMA

Frozen sections of primary and metastatic human renal cell carcinoma ( RCC) were analyzed for the expression of endogeneous binding sites for carbohydrates. Fluorescent neoglycoproteins, carrying chemically link ed carbohydrate residues on bovine serum albumin as a carrier protein, were applied to 44 primary tumor specimens. In the majority of specim ens, accessible binding sites with specificity for maltose and N-acety lgalactosamine were detected. In specimens of normal kidney no specifi c binding of carbohydrate ligands was observed under these experimenta l conditions. Specimens of both the primary tumor and a metastasis wer e available in 10 cases. When the expression of specific binding sites of primary tumors and metastases was compared, the respective pattern s were similar with no clear gain or loss of certain lectins in the me tastases. We conclude that binding sites with specificity for maltose and N-acetylgalactosamine are present on human RCC and their correspon ding metastases.