Characterization of low- and high-metastatic clones isolated from a Lewis lung carcinoma.

Cloned cell lines with low and high metastatic potentials were established from a Lewis lung carcinoma. Those with a high metastatic potential, LM12 -3-II cells, grew slower than those with a low potential, P-29 cells, both in vivo and in vitro. No significant difference between these cell lines was found in their susceptibility to natural killer cell-mediated lysis in vitro. Both LM12 -3-II and P-29 cells showed poor organization of microfilament bundles containing actin. LM-12-3-II cells showed lower cloning efficiency in semisolid 0.3% and 0.6% agar medium, lower lysosomal enzyme activities and lower homotypic aggregation than P-29 cells. LM12 -3-II cells adhered to monolayers of endothelial cells more slowly than P-29 cells, although they adhered to a subendothelial matrix a little more rapidly than P-29 cells. On the other hand, LM12 -3-II cells adhered to the surface of plastic culture dishes more firmly than P-29 cells. The neuraminidase-accessible sialic acid of LM12 -3-II cells was less than that of P-29 cells. Thus, the firmness of adhesion was positively correlated with the metastatic potential in these cells.