|
Mitotic arrest is a cell-cycle state in which a cell is prevented
from completing mitosis, usually because the spindle-assembly checkpoint detects
improper chromosome alignment, defective kinetochore attachment, spindle damage,
or incomplete chromosome segregation. Mitotic arrest commonly occurs during
metaphase and is associated with sustained cyclin B1/CDK1 activity, checkpoint
proteins such as MAD2, BUB1, BUBR1, and MPS1, and inhibition of the
anaphase-promoting complex/cyclosome (APC/C).
In cancer cells, prolonged mitotic arrest may suppress tumour growth by preventing
cell division and can lead to apoptosis, mitotic catastrophe, senescence, or
abnormal exit from mitosis. Compounds that disrupt microtubules, centrosomes,
kinetochores, or spindle-checkpoint signalling frequently induce mitotic arrest.
However, some cells escape through mitotic slippage, which may produce
polyploid or genetically unstable surviving cells.
Generally favourable anticancer direction: increased or prolonged
mitotic arrest in tumour cells, particularly when followed by apoptosis or
mitotic catastrophe. The effect should be interpreted cautiously if the study
also reports mitotic slippage, polyploidy, or survival of genomically unstable cells.
|