[Expression of the traits characterizing the cell surface in hybrids of malignant and nonmalignant cells]

Hybrids between non-malignant mouse 3T3 cells and highly malignant rat JF1 cells were selected in semisolid agar medium without asparagine: 3T3 cells do not grow in agar; JF1 cells required asparagine for their growth. Some surface properties: agglutination by Con A, saturation density, electrophoretic mobility and behaviour in the two-phase aqueous polymer system dextran-polyethylenglycol, -have been studied in the parental cells and in two their hybrids (H9-1 and H9-2). JF1 cells differ from 3T3 cells in their behaviour in two phase polymer system by lower electrophoretic mobility, by higher agglutinability with Con A and higher saturation density. H9-1 and H9-2 hybrids behave in two phase polymer system similar to 3T3 cells, they have low saturation density, intermediate electrophoretic mobility and intermediate agglutinability by Con A. These results indicate that in hybrids between non-malignant 3T3 cells and malignant JF1 cells selected under conditions (semisolid agar) favorite for the growth of oncogenic cells, surface properties of malignant parents are not dominated. Both hybrids are phenotypically similar with drastic genetical difference. By means of C-banding it has been shown that H9-2 hybrid contain approximately one 3T3 and one JF1 genome; H9-1 hybrid contains two JF1 genomes and about 15% of 3T3 genome.