Harald Sontheimer isolated the peptide chlorotoxin from the venom of the giant Israeli Scorpion (Leiurus quinquestriatus). The peptide appears to kill only the cancerous cells in the brain. Unlike chemotherapy, which destroys both healthy and cancerous cells, the venom of this scorpion tracks down and destroys only tumor cells.

Sontheimer and his colleagues have genetically modified the chlorotoxin by attaching a chemotherapeutic agent, samporin, to it that only attacks the cells it binds to. The fact that chlorotoxin only binds to the cancerous cells gives the scientists confidence that this method could be an effective treatment for the malicious disease.

The concept is to use the peptides to direct the action of chemotherapy agents only to the cancerous cells. The neurobiologist hopes that this kind of treatment will not cause damage to the patient’s mental capacity, since the combination of chlorotoxin and samporin targets just the tumor cells.

The use of scorpion venom to fight glioma complements other scientific research in recent years on how animal poisons can be used in the treatment of human diseases. For example, a protein found in snake venom, which causes heavy bleeding to death, can be useful in small doses. A small quantity of it can stop blood from clotting and could be an effective treatment for heart disease and stroke.

Israeli scorpions are found in the Middle East. They reach 5 inches (12 cm) in length and use their venom to paralyze their prey.

Info by John Roach