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Invasive activity, spreading on and chemotactic response to laminin are properties of high but not low metastatic mouse osteosarcoma cells.

We have examined the interactions of low (Os43 and OS48) and high (Os50/K8 and Os50/K12) metastatic cell lines derived from osteosarcomas (Os) of the Balb/c mouse with fibronectin (FN) and laminin (LN). All of these cell lines formed osteogenic tumors when transplanted subcutaneously into syngeneic mice. Os43 and Os48 cells gave rise to few metastases while the Os50/K8 and Os50/K12 cells were highly metastatic. In an in vitro chemoinvasion assay only the highly metastatic cells were able to invade a reconstituted basement membrane. Although the interactions of all cell lines with FN were quite similar, their response to LN differed considerably. Within each of the cell lines, chemotactic response to and cell spreading on LN were closely correlated. Highly metastatic Os cells migrated to and spread on LN substrates to a much greater extent than low metastatic cells. Os43 and particularly Os48 showed very much low migration to LN, similar to that of Balb/c 3T3 fibroblasts. They also spread poorly on LN, resembling the behavior of normal human bone cells which were used as a control. Thus, with these assays it is possible to distinguish the LN interactions associated with the metastatic phenotype of Os cells. The acquisition of LN recognition in tumor cells of bone origin may be related to their ability to invade and metastasize. This system may be valuable for the study of LN recognition molecules, their appearance, or changes with the metastatic phenotype.