The effect of several antitumor agents on 3H-TTP incorporation in host liver and hepatoma nuclei.

Six different tumor antibiotics have been investigated in a nuclear incorporating system for their ability to inhibit 3H-TTP incorporation. Both host liver nuclei and nuclei prepared from two different Morris hepatomas have been used in the investigation. Three of these anti-tumor agents inhibit 3H-TTP incorporation equally in host liver and hepatoma nuclei, two preferentially inhibit incorporation in hepatoma nuclei and one stimulates incorporation preferentially in host liver nuclei. The effects of these compounds on nuclear DNA has been analyzed on neutral and alkaline sucrose density gradients. The nuclear incorporation system appears to be useful as a screening test system for potential anti-tumor agents.