Effects of daunomycin and its macromolecular analog daunophilin on the proliferation of mammalian cells.

Effects of daunomycin and daunomycin bound to an HPMA copolymer (daunophilin) on the proliferation of mammalian cells cultivated in vitro were compared. One line of non-tumor cells (LEP human cells) and two tumor cell lines (human HeLa cells and C6 rat cells) were used. It was found that both daunomycin and daunophilin had an inhibitory effect on the proliferation of the three cell lines and that the effect was irreversible.

The effect of second generation platinum cytostatics on mammalian cell proliferation.

The effect of three second generation platinum complexes on proliferation of tumor cells (HeLa, C6) and nontumor cells (LEP) was studied, and compared with that of cis-DDP. The highest activity, comparable with cis-DDP, was exhibited by oxoplatinum. CBDCA was somewhat less active in this system, but had a greater effect on both lines of tumor cells than on nontumor cells.

The effect of 3H-thymidine on the proliferation of in vitro cultured mammalian cells.

The effect of 3H-thymidine on the proliferation of Chinese hamster cells (clone V79) was studied. Following 3H-thymidine application the proliferation of cells (studied on the basis of plating efficiency) was found to be diminished, the drop being dependent on radioactivity (2-20 kBq/ml cultivation medium), the time of application (2-20 h) and specific activity of 3H-thymidine added. Exogenous macromolecular DNA was able to repair, to an important degree the radiotoxic effect of 3H-thymidine on V79 cells by a mechanism other than the mere reduction of specific activity of 3H-thymidine.

Isolated fractions of the growth-promoting alpha-globulin stimulate differently the incorporation of exogenous DNA into L cells.

The growth-promoting alpha-globulin necessary for long-term cultivation of mammalian cells in serum-free medium is a complex of several proteins which also stimulates the incorporation of exogenous DNA into recipient L cells. Biological activity responsible for the stimulation of DNA incorporation into L cells can be concentrated because one of two major protein components, compared to the whole GPAG complex, increases incorporation into cell nuclei by 100%.