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