Binding of daunomycin to DNA and the inhibition of RNA and DNA synthesis.

With synchronized tissue culture cells (L929), daunomycin had the greatest inhibitory effect on cell growth when the drug was administered during the later stages of cell division (late S, G2, and M). The level of binding of daunomycin to DNA was not found to be influenced by the phase of the cell cycle. The highest level of radioactivity from [eH]-daunomycin was bound to DNA of the heterochromatin fraction.