Cancer cells kill off healthy neighbours

Cancer cells create space to grow by killing off surrounding healthy cells, according to UK researchers working with fruit flies.

Their discovery could point to new ways of holding early tumours at bay, but further studies in human cells will be needed to confirm the findings.

The study – funded by Cancer Research UK and published in the journal Current Biology – may explain how cancer cells corrupt a ‘quality control’ mechanism in tissues that is usually responsible for removing damaged or underperforming cells.

Dr Alan Worsley, senior science information officer at Cancer Research UK said the ‘intriguing’ results could help turn healthy cells into a barrier to tumours, but cautioned that further research was needed.
 
“Tumours often need to elbow healthy cells out of the way in order to grow,” he said.
 
“This intriguing study in fruit flies suggests that if researchers can turn off the signals that tell healthy cells to die, they could act as a barrier that boxes cancer cells in and stunts their growth.

“We don’t yet know if the same thing would work in patients, but it highlights an ingenious new approach that could help to keep early stage cancers in check.”
 
The researchers, based at the Wellcome Trust/Cancer Research UK Gurdon Institute at the University of Cambridge, worked with fruit flies which had been genetically engineered to develop tumours in their intestines. They showed for the first time that expanding tumours trigger neighbouring healthy cells into initiating a cellular suicide mechanism called apoptosis.

But in flies that were engineered so these surrounding healthy cells were resistant to the trigger, the scientists found they were able to contain the tumour and stop it from spreading.

While further research in human cells is still needed, drugs which inhibit cell death are already being trialled in the prevention of organ damage, and if they are proven to be safe they could be tested as a possible way to halt tumour growth.

Study leader Dr Eugenia Piddini also believes the team’s findings may explain how cancer cells that have spread may trigger damage and failure of these distant organs by killing off healthy residents.
 
“We know that as cancer spreads through the body it can cause organ failure,” she said. “Our finding suggests a possible explanation for this: if the tumour kills surrounding cells, there will come a point where there are no longer enough healthy cells for the organ to continue to function.”

“It sounds counterintuitive not to encourage cell death, as this means you’re not attacking the tumour itself,” she added. “But if we think of it like an army fighting a titan, it makes sense that if you protect your soldiers and stop them dying, you stand a better chance of containing – and even killing – your enemy.”