This monoclonal antibody recognises a 100kd nuclear protein which is expressed in the cell cycle phases S, G2 and M.

The Ki-S2:Ki-67 ratio, the cell cycling ratio, represents the relative cell fraction in the cycle compartment after the critical G1/S transition. The complementary value corresponds to the relative percentage of cells in G1: a high percentage G1 cells indicates slow progression or accumulation at the G1/S boundary caused by transient cell cycle arrest.


A high cycling ratio has been shown to be a strong predictor of poor prognosis in node-negative breast carcinoma1.



1Rudolph, P., Alm, P., Olsson, H., Heidebrecht, H. J., Ferno, M., Baldetorp, B., Parwaresch, R. Concurrent overexpression of p53 and c-erbB-2 correlates with accelerated cycling and concomitant poor prognosis in node-negative breast cancer. Human Pathol 2001;32:311-319.

This page last revised 6.11.2001.

©SMUHT/PW Bishop