Sugar Receptors of Different Types in Human Metastases to Lung and Liver

Abstract

Endogenous sugar receptors of human tumors, supposedly involved in recogni-tive interactions and growth regulation, were comparatively analyzed from human metastases to lung and liver by affinity chromatography and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These profiles of sugar receptors including Ca²⁺-depen-dent and Ca²⁺-independent specificities to α- and β-galactosides, α-mannosyl and α-fucosyl moieties from salt and detergent extracts were found to be significantly different from the profile of the corresponding normal tissue. Metastatic lesions to lung from three different types of primary tumors revealed primarily tumor-associated mannan- and galactoside-binding proteins, whereas different liver metastases showed a tendency towards preferential expression of additional β-galactoside-binding proteins and, to a reduced extent, fucose-binding proteins. The patterns of two metastatic lesions to lung and liver from a similar primary tumor, a colon carcinoma, disclose significant differences. Each resembles the pattern of other metastases to the same target organ more than it resembles the pattern of metastatic lesions to the other target organ, derived from a similar primary tumor. Further analyses of two primary liver tumors underscore the significance of changes in such a pattern upon malignant transformation.