British scientists have uncovered a vital clue to stopping cancers spreading around the body, the BBC reported on Friday.

Researchers from the London Research Institute discovered that a protein called Tes is able to block a second protein, Mena, from helping cancer cells "crawl" away from the initial tumor.

Unlike the Mena protein, Tes is absent in many tumors and has not been well studied.

Equipped with instruments including X-ray crystallography, which can be used to determine the three-dimensional structure of a molecule, the researchers found that Tes attached itself to Menain such a way it could no longer bind with other proteins.

Study leader Michael Way was quoted as saying that if researchers could design a drug to block Mena in the same way as Tes, it would potentially be a way to stop the spread of cancer once a tumor had formed.

"What was surprising was, when you look at Tes you wouldn't predict it would interact with Mena. Looking at the structure gives us clues in designing drugs which mimic the interaction with Tes and prevent cells from migrating, although that's a long way away," he told the BBC.

Way said Mena is a very small part of the spread of cancer cells, but that is one of the control mechanisms that goes wrong.

The research team claimed that this knowledge should help in the design of new drug treatments to anchor a tumor in one site.

(Xinhua News Agency December 29, 2007)