Adhesiveness and morphology of Lewis lung carcinoma variants influence their sensitivity to natural killer cytolysis and their metastatic capacity.

Cloned metastatic Lewis lung carcinoma cells, C3, were more resistant to natural killer (NK) lysis than were nonmetastatic variant cells, C8. This was influenced by the tumor cell adhesiveness and morphology. When the nonadherent round C3 cells were cultured with dimethylsulfoxide, they became adherent and spread, sensitive to NK lysis and less metastatic. When the adherent and spread C8 cells were made nonadherent and round with cytochalasin B, they became more resistant to NK lysis and more metastatic. These metastatic differences were not observed in 3-week-old NK-deficient mice.