[Several properties of the nucleic acide of nuclei and mitochondria from hepatoma induced by N-nitroso-N-diethylamine].

The work was undertaken to estimate quantitatively the functional activity of tumor cell genome and possible variations in the relationship between nuclear genome and mitochondrial genetic determinants in tumor cell. For this purpose in mice C3HA tumors of hepatocellular origin were induced with N-nitroso-N-diethylamine, tissues of one of which were subjected to successive isologous transplantation during the period over 3 years. Normal hepatic tissues were taken for the control. As a result of a series of independent experiments (actinomycin D spectrophotometric titration, acridine orange binding, template activity, nuclear RNA/DNA hybridization) the results were obtained indicating a decrease in the amount of active loci in tumor hepatocytes genome. Hybridization data also indicate that in the tumor the derepression of chromosomal genes responsible for the genetic control over mitochondria and a non-regulated de-repression of mitochondrial genetic determinants take place.