Scientists home in on death gene

Cancer Research UK scientists in Scotland have pinpointed the location of a gene that may be crucial for a timely death, according to a study¹ published today.

Researchers have narrowed the search for the gene to a tiny section of chromosome four – one of the bundles of DNA containing our genes – putting them on the brink of an important discovery.

They believe the gene may form part of the internal controls that in healthy tissue prevent cells from living and dividing indefinitely. Understanding how these controls go wrong in cancer will be crucial for developing new treatments aimed at restoring mortality to tumours.

Genes which trigger cell death, or which stop cells from dividing, are vital for keeping the number of cells in the body in balance. But cancer cells have various defects that keep them alive and allow them to divide well beyond their allotted lifespan.

Researchers at the Cancer Research UK Beatson Laboratories in Glasgow had previously discovered that in cervical cancer cells one of these defects involves the loss of part of chromosome four.

In the new study, researchers used a range of genetic techniques to narrow the search for the gene within this stretch of DNA. They believe the gene they are tracking may be vital for making sure healthy cells don’t live too long.

Lead researcher Dr Ken Parkinson says: “Cancer cells are good survivors – not only do they rapidly grow and spread but they also refuse to die.

“If we can find the genetic fault responsible for their survival, we can begin to look at ways of making the cells vulnerable to dying once again. A crucial part of this process will be the isolation of genes which in healthy tissue promote cell death, such as the gene we are tracking now.”

Researchers created miniature cells that only contain one copy of chromosome four and fused them to cervical cancer cells, introducing into each cell an extra copy of the chromosome.

They found that some cancer cells died while others continued dividing and growing. When they examined the cancer cells that carried on growing, they found that most had lost the same small region on the introduced chromosome four.

Dr Parkinson says: “We know that this region harbours the gene because when it is disrupted or missing cervical cancer cells grow out of control.

“We will now be concentrating our efforts on the final step of isolating and properly describing the gene, which will give us an important tool for future research into cancer therapies.”

Dr Richard Sullivan, Cancer Research UK’s Head of Clinical Programmes, says: “Cancer arises when our genes are damaged. Locating which genes are involved is a vital step in understanding why cancer behaves the way it does and designing treatments to combat the disease.”

ENDS

1. Neoplasia4 (6) pp.544 – 550