Scientists hope to draw cancer cells from body

In collaboration with the Press Association

An American scientist has made a discovery about the way cells move through the bloodstream that could one day enable mobile cancer cells to be removed from the body, preventing the disease from spreading.

Michael King, associate professor of biomedical engineering at the University of Rochester, noticed that when white blood cells approach an injury site, they are drawn towards proteins called selectins on the blood vessel wall.

They then roll more slowly than usual through the blood vessel - being held back to a certain extent by the sticky selectin proteins - until they meet a signal on the vessel wall telling them to leave the bloodstream and enter the site of infection.

Professor King discovered that the same process occurs when stem cells move in and out of bone tissue. He was able to capture living stem cells by coating a material with adhesive proteins and inserting it into the bloodstream of a rat for a couple of hours. This technique was so effective that more than 25 per cent of the sample was stem cells.

The assistant professor revealed: "I was astounded. It's amazing because even when you use drugs to increase the number of free stem cells in the blood, they still only make up less than one per cent of all cells."

The findings are published in the British Journal of Haematology and the researchers are now trying to create a device that will do the same with cancerous cells, which use the same rolling mechanism when they spread throughout the body.

"One of our ultimate goals is to develop an implantable device that will selectively remove metastatic cells from the blood," the professor said. "Those cells can predate detectable tumours by years, so we might catch them before they become dangerous."

Read the British Journal of Haematology abstract online

Find out more about how cancer cells spread