GROWTH INVITRO OF TUMOR-CELL BY FIBROBLAST HYBRIDS IN WHICH MALIGNANCY IS SUPPRESSED

Abstract

The growth in vitro of a lymphoma .times. fibroblast hybrid and several melanoma .times. fibroblast hybrids in which malignancy is suppressed was studied. The parental cells, hybrids and malignant segregants derived from the hybrids were analyzed for serum requirement, cloning efficiency in soft agarose, density dependent inhibition of growth and secretion of plasminogen activating enzyme. One malignant segregant from the lymphoma .times. fibroblast cross had a more highly transformed phenotype than the hybrid from which it was derived. In the case of the melanoma .times. fibroblast crosses, none of the parameters examined could be correlated in a direct way with malignancy.