[The organizational characteristics of the nucleolar region in the diploid and polyploid nuclei of neoplastic hepatocytes during dipin-induced carcinogenesis].

The use of the number of nucleoli as a criterion allowed us to identify significant differences in the organization of nucleoli in newly formed hepatocytes under the conditions of dipine-induced carcinogenesis 8-10 weeks after its initiation, as compared with normal liver cells of adult mice. The number of nucleoli in tetraploid new hepatocytes was equal to that in the diploid nuclei of normal liver (on average 3.5 and 3.6, respectively) and the number in the new octaploid nuclei was equal to that in tetraploid (6.2 and 6.4, respectively). A higher extent of association of nucleolar organizers under the conditions of endoreproduction or the association of homologous chromosomes in G1 period of the cell cycle is discussed as a possible mechanism responsible for the decrease in the number of nucleoli.