Sign up for Table of Contents Alerts.

Email this page

Print this page

Perspectives

Caspase-independent mitotic death (CIMD)

Katsumi Kitagawa and Yohei Niikura

This is an open-access article

 Download PDF

If the document does not open, please right-click on the link (control-click on a Macintosh) and select the option to save the file to disk.

The spindle checkpoint, which monitors kinetochore–microtubule attachment, is required for high fidelity of chromosome transmission. A failure in this mechanism causes aneuploidy, thereby promoting progression to tumorigenesis. However, the cell death mechanism that prevents the aneuploidy caused by failure of the spindle checkpoint is yet unknown. We have recently identified a novel type of mitotic cell death, which we term caspase-independent mitotic death (CIMD). In BUB1-deficient (but not MAD2-deficient) cells, CIMD is induced by conditions that activate the spindle checkpoint (i.e., cold shock or treatment with nocodazole, paclitaxel, or 17-AAG [17-allylaminogeldanamycin]). CIMD depends on p73, a homolog of p53, but not on p53. It also depends on the apoptosis-inducing factor (AIF) and endonuclease G (Endo G), which are effectors of caspase-independent cell death. When BUB1 is completely depleted, aneuploidy occurs instead of CIMD. We propose that CIMD can be the cell death mechanism that protects cells from aneuploidy by inducing the death of cells prone to substantial chromosome missegregation. Our study also shows that previous evaluations of the spindle checkpoint activity in mutant or cancer cells by monitoring mitotic index could be misleading.

Authors

Katsumi Kitagawa

St. Jude's Children's Research Hospital; Memphis, TN

Yohei Niikura

St. Jude's Children's Research Hospital; Memphis, TN

This is an open-access article

 Download PDF

If the document does not open, please right-click on the link (control-click on a Macintosh) and select the option to save the file to disk.