Cell-surface laminin-like molecules and alpha-D-galactopyranosyl end-groups of cloned strongly and weakly metastatic murine fibrosarcoma cells.

Indications from previous work that cancer cell-surface laminin-like molecules and alpha-D-galactopyranosyl end-groups may contribute to spontaneous metastasis were further investigated. Both moieties are known to mediate cell attachment to various foreign surfaces. Five strongly metastatic and 5 weakly metastatic cell clones from a murine fibrosarcoma were examined for the occurrence of both cell-surface moieties by immunofluorescence flow cytometry and microscopy. None of these clones was rich in laminin-like molecules, which were least strongly expressed by the highly metastatic clones. The alpha-D-galactopyranosyl end-groups were strongly expressed by all strongly metastatic clones and by 2 weakly metastatic clones, but were only weakly expressed by the other weakly metastatic clones. These results indicate that the laminin-like cell-surface molecules are not necessary for spontaneous metastasis formation. However, the alpha-D-galactopyranosyl end-groups may be necessary, but are not sufficient for the cancer cells to form metastases. These carbohydrates are known to occur on the laminin-like molecules. The present results show that they must also exist on other cell-surface molecules.