TY - JOUR
T1 - Presence of two cytogenetic forms of amplified dna
T2 - Evidence for a role in tumor growth in an intraspecific mouse hybrid cell line
AU - Wigley, Caroline B.
AU - Cowell, John Kenneth
PY - 1984/1/1
Y1 - 1984/1/1
N2 - An intraspecific mouse hybrid epithelial cell line, F5/B, is described in which the homogeneously staining region (HSR)-containing marker chromosome from one parent is absent in about half of the cells. It is replaced in these cells by double minutes (DM), an alternative form of amplified DNA, which is liable to loss because of its instability at mitosis. DM probably arise from the breakdown of the HSR during clonal growth of F5/B. Subclones were derived possessing one or another cytogenetic feature, and their cloning efficiency in vitro and tumorigenicity in syngeneic animals were compared. There were no differences in in vitro tumorigenicity, but in vivo DM-containing subclones were significantly less tumorigenic than HSR-containing subclones or the F5/B parent hybrid. In tumors that developed after long latent periods, cells had increased numbers of DM compared with the inoculated population, demonstrating a selective advantage in vivo for cells with a high DM content. These results indicate a role for the amplified DNA in tumor growth.
AB - An intraspecific mouse hybrid epithelial cell line, F5/B, is described in which the homogeneously staining region (HSR)-containing marker chromosome from one parent is absent in about half of the cells. It is replaced in these cells by double minutes (DM), an alternative form of amplified DNA, which is liable to loss because of its instability at mitosis. DM probably arise from the breakdown of the HSR during clonal growth of F5/B. Subclones were derived possessing one or another cytogenetic feature, and their cloning efficiency in vitro and tumorigenicity in syngeneic animals were compared. There were no differences in in vitro tumorigenicity, but in vivo DM-containing subclones were significantly less tumorigenic than HSR-containing subclones or the F5/B parent hybrid. In tumors that developed after long latent periods, cells had increased numbers of DM compared with the inoculated population, demonstrating a selective advantage in vivo for cells with a high DM content. These results indicate a role for the amplified DNA in tumor growth.
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U2 - 10.1093/jnci/73.1.219
DO - 10.1093/jnci/73.1.219
M3 - Article
C2 - 6588226
AN - SCOPUS:0021252968
SN - 0027-8874
VL - 73
SP - 219
EP - 226
JO - Journal of the National Cancer Institute
JF - Journal of the National Cancer Institute
IS - 1
ER -