[Damage to the supramolecular DNA complex in the mechanism of action of antitumor drugs].

The report deals with damaging effects on the structure of a supramolecular DNA complex of leukemic cells in P388 mice, susceptible to most antitumor preparations, following treatment with therapeutic doses of sarcolysin, methylnitrosourea, actinomycin D and adriamycin. Capillary elastoviscosimetry and nucleoid sedimentation procedure showed that damage to supramolecular DNA complex structure became apparent as quickly as 15-60 min after injection of the said preparations and persisted for several days. The said damage consisted in DNA's filaments rupture and alterations in higher-order chromatin structures. The role of conformational changes of supramolecular DNA complex in the course of the cytotoxic action of antitumor agents is discussed.