Development of tetraploidy in V79 spheroids
Chinese hamster V-79-171 cells, when placed in suspension culture, spontaneously form multicell spheroids. As the spheroids enlarge the fraction of polyploid (predominantly tetraploid) cells increases and can approach 100% in very large spheroids. Spheroid size, rather than age, seems to be a major determinant for increased ploidy. When cell separation techniques were used to select enriched populations of diploid and tetraploid cells, the growth rate and plating efficiency of the diploid cells was always marginally higher, and they gradually became predominant in mixed monolayer cultures. Cloned tetraploid cells, however, generally remained quite stable, and no consistent ploidy dependent changes in radiosensitivity were observed relative to normal, diploid cell lines.
Key wordsspheroids tetraploidy flow cytometry
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- 1.Sutherland, R. M.; Durand, R. E. Radiation response of multicell spheroids: An in vitro tumor model. Curr. Top. Radiat. Res. Quart. 11: 87–139; 1976.Google Scholar
- 3.Durand, R. E.; Olive, P. L. Evaluation of nitroheterocyclic radiosensitizers using spheroids. Lett, J., ed. Advances in Radiation Biology. Vol. 9. New York: Academic Press, 1981: 79–104.Google Scholar
- 9.Vindelov, L. L. Flow microfluorometric analysis of nuclear DNA in cells from solid tumors and cell suspensions. A new method for rapid isolation and staining of nuclei. Virchows Arch. [Cell Pathol.] 24: 227–242; 1977.Google Scholar
- 10.Oksala, T. Mitotic abnormalities and cancer. German, J. ed. Chromosomes and cancer. New York: John Wiley and Sons; 1974: 239–261.Google Scholar