The venom used by scorpions to paralyse their prey could be the next big thing to fight cancer.

Professor Harold Sontheimer from the University of Alabama says he has isolated a special protein from the venom which has been used successfully to attack the tumour cells of a deadly type of brain cancer that cannot currently be treated.

Cancer of the glial cells, the supporting cells in the brain, affects 60 to 80,000 people worldwide, and kills the vast majority of them within a year of diagnosis.

The tumour cells spread quickly to other parts of the brain and chemotherapy is deemed too dangerous since it would likely destroy the healthy cells as well as the cancerous ones.

But Professor Sontheimer believes that the giant Israeli scorpion - a creature about 12 cm (five inches) long - may provide the solution. Its venom contains special proteins, or peptides, that can target and shut down a prey's nervous system.

Specificty

One of the peptides in particular - chlorotoxin - seems capable of tracking down and destroying only the cancerous cells in the brain. "The importance here is that this particular peptide from this particular scorpion doesn't bind to any other protein expressed in any healthy cell in the body."

Harold Sontheimer: Success in the lab

The idea is to use these peptides to transport chemotherapy agents directly to the diseased cells, and Sontheimer's team have already had success with this technique in the test tube and in animal trials.

They have also been able to use bacteria to grow up large amounts of the peptide, which they hope will also be effective in fighting other forms of cancer.

Professor Sontheimer told the American Association for the Advancement of the Science (AAAS) in Anaheim, USA, that there was still much work to do but that he hoped to move towards human trials shortly.

"We're in late stages of animal testing ... and we hope we'll be in patients later this year.

"This poison from the scorpion does find, very reliably, tumour cells in the brains of animals - so that gives us a great deal of confidence that this will also occur in humans."