F. Zolzer et al., EVIDENCE FOR QUIESCENT S-PHASE AND G(2)-PHASE CELLS IN HUMAN COLORECTAL CARCINOMAS - A FLOW CYTOMETRIC STUDY WITH THE KI-67 ANTIBODY, Cell proliferation, 28(6), 1995, pp. 313-327
The expression of certain antigens specific for proliferating cells ca
n be determined simultaneously with cell cycle distribution by means o
f two-dimensional flow cytometry. In this way, a tumour's growth poten
tial is characterized more precisely than with any one parameter alone
. Here we describe such simultaneous measurements of DNA content and l
abelling with the Ki-67 antibody that distinguishes between cycling an
d non-cycling cells. Having overcome a number of technical problems we
were able to analyse material from 29 biopsies of human colorectal tu
mours. In a number of cases, Ki-67 negative cells were found with a DN
A-content of G(0/1) only, whereas all cells with an S- or G(2)-phase D
NA-content were Ki-67 positive. There were other cases in which cells
with an S- and G(2)-phase DNA-content had obviously become quiescent (
Ki-67 negative), sometimes even outnumbering the proliferating (Ki-67
positive) cells in the respective compartments of the cycle. Generally
, however, when Ki-67 negative and positive subpopulations were analys
ed separately It was found that the former had a significantly lower (
S + G(2))-phase fraction than the latter. There was evidence for a cor
relation between Ki-67 index and (S + G(2))-phase fraction at least in
the subgroup of aneuploid tumours. Neither of the two parameters was
correlated with stage according to Duke's classification or tumour siz
e, However, a positive correlation was found between the fraction of u
nlabelled S- and G(2)-phase cells and tumour size as reflected in the
T category.