Mg. Dewald et al., HETEROGENEITY IN THE MITOTIC CHECKPOINT CONTROL OF BALB 3T3 CELLS ANDA CORRELATION WITH GENE AMPLIFICATION PROPENSITY/, Cancer research, 54(19), 1994, pp. 5064-5070
Chinese hamster ovary (and many rodent cell lines) transiently delay m
itosis and progress into a second cell cycle without undergoing cytoki
nesis when treated with Colcemid, whereas HeLaS3 (and most human cell
lines) arrest permanently in mitosis. We have discussed these differen
ces and their consequences for cell survival under cell cycle-perturbi
ng conditions within the context of mitotic checkpoint control (Schimk
e et al., Cold Spring Harbor Symp. Quant. Biol., 56: 417-425, 1991). H
ere, we report studies with mouse BALB/3T3 cell populations which, by
the criterion of response to Colcemid, constitute a heterogeneous popu
lation with respect to mitotic checkpoint control. Clonal and subclona
l populations retain population heterogeneity but with a bias for enri
chment of cell populations that respond as do HeLaS3 cells. We have an
alyzed clones for their propensity for gene amplification as assessed
by a stepwise increment selection protocol in methotrexate and report
that there are significant differences in amplification propensities t
hat correlate with differences in mitotic checkpoint control propertie
s.