Key element of cell division uncovered

In dividing human cells, chromosomes are duplicated, and one copy is passed onto each daughter cell, but some cells with an unequal number of chromosomes bypass the body’s in-built health checkpoint.

Scientists at Warwick Medical School studied simple yeast cells and have uncovered the mechanism by which cells ensure their daughter cells receive the correct number of chromosomes.

Cell division in monitored by the body, but if the process is disturbed, daughter cells can receive an unequal number of chromosomes, a state that can drive cells to become cancerous.

“This cell division is monitored by the body’s surveillance system known as the ‘spindle checkpoint’, and that is only switched off once everything within the cell is set up correctly,” said Professor Jonathan Millar.

Millar said these elements are all conserved from yeast to human cells; therefore what happens in yeast is likely to happen in human cells. Their work has been published in Developmental Cell.

“By preventing this process happening with drugs, you could restrict the cells ability to develop full blown cancer,” said Millar.

Taxanes are one of the most frequently used class of anti-cancer drugs, and target the mitotic apparatus in part by preventing proper silencing of the spindle checkpoint. However, the drugs affect both healthy and cancerous cells, and can have debilitating neurological damage and hair loss.

“Now that we have pinpointed the central element for cell division, we are in a great position to design drugs that can be more selective and targeted about the cells they treat,” said Millar.

“But this is just the start – much more research has to be dome before we can convert this into a commercial treatment for patients, but we are greatly encourages that our research here at Warwick is leading the way in the search for more effective cancer treatments with fewer side effects.”

Spindle checkpoint silencing requires association of PP1 to both Spc7 and Kinesin-8 motors