• 6/5/2007
  • London, UK
  • staff
  • Channel 4 News (www.channel4.com)

Researchers hope the discovery will lead to new treatments for the disease.

Study leader Professor Michael Clarke, from Stanford University in California, said: “This work will enable us to better understand how to identify these cells, and to do molecular studies to find potential new therapies.”

Prof Clarke was the first to find cancer stem cells in a solid tumour – in this case breast cancer – in 2003. Other cancer stem cells have also been found in head and neck and pancreatic tumours.

Cancer stem cells act as well springs, constantly dividing to produce new tumour cells. They are thought to be the main reason why some cancers return after apparently successful treatment.

Although chemotherapy might kill the bulk of tumour cells, any stem cells that remain will allow the cancer to resurface or spread. Treatments that target cancer stem cells would allow the cancer to be eradicated entirely.

Dr Irving Weissman, director of Stanford’s Institute for Stem Cell Biology and Regenerative Medicine, said: “We have brought together a team of scientists and clinicians who will help find the weak points in cancer, devise new immune and molecular diagnostics and therapeutics, test them in mice that carry the cancer stem cells and, hopefully, in a few years begin to test them in our patients.”

Identifying the bowel cancer stem cells has highlighted the importance of a protein called CD44. Scientists found it dotting the surface of breast and head and neck cancer stem cells, as well as those from bowel tumours.

A novel protein called CD166, not seen before in cancer stem cells, was also found on the bowel cancer cells. “This protein could be a unique target for identifying and treating colorectal cancers,” said Dr Piero Dalerba, another member of the Stanford team.

The findings are published in the journal Proceedings of the National Academy of Sciences.