Differential expression of endogenous lectins on the surface of nontumorigenic, tumorigenic, and metastatic cells

A monoclonal antibody that was found to recognize endogenous galactoside-specific lectins of various tumor cells by immunoblot analysis was used for quantitative analyses of cell surface lectin on nontumorigenic, tumorigenic, and metastatic cells of diverse histological types and origin. Indirect immunofluorescent staining of viable cells followed by analysis with a fluorescence-activated cell sorter revealed marked differences in the amount of surface lectins between untransformed and malignant cells. While lectin was either absent or present in a very low density on the surface of normal cells, neoplastic cells were invariably stained by the antilectin antibodies. Furthermore, among related tumor cell variants of the K-1735 melanoma and UV-2237 fibrosarcoma tumor systems, cells exhibiting a higher lung-colonizing potential also expressed higher levels of cell surface lectin. These results suggest that the presence of a lectin on the cell surface may be related to neoplastic transformation and progression toward metastasis.