July 28, 2006
Venom protein may lead to brain cancer cure- study
By Amanda Beck
WASHINGTON (Reuters) - Doctors seeking treatments for
malignant brain tumors have found promise in the venom of
scorpions, according to a study released on Friday.
The study showed that a synthetic version of a protein
found in the venom of giant yellow Israeli scorpions targeted
tumor cells but did not harm the healthy cells of brain cancer
"We're testing a new agent that has a lot of potential for
patients who have had no meaningful treatments thus far," said
Dr. Adam Mamelak, lead author on an article to appear in the
August issue of the Journal of Clinical Oncology.
In the study, 18 patients first had surgery to remove
malignant gliomas, a lethal kind of brain tumor. Then doctors
injected their brains with a solution of radioactive iodine and
TM-601, the synthetic protein.
The solution bound almost exclusively to leftover tumor
cells, suggesting that it could be combined with chemotherapy
to fight cancer. Furthermore, two study patients were still
alive nearly three years after the treatment.
Because life expectancy for the 14,000 annual glioma
patients in the United States is typically a matter of months,
the results shore up animal research indicating that the venom
protein may inhibit tumor growth even without a radioactive
component, Mamelak said.
"Does that mean that the drug was miraculous? No," said
Mamelak, a neurosurgeon at Cedars-Sinai Medical Center in Los
Angeles. "But we have shown that it is safe and that we should
at least move forward."
The synthetic scorpion venom was developed by
Transmolecular Industries, Inc., a Boston-based company, and is
one of several medicines recently derived from animal poisons.
Other researchers are investigating whether a protein in
snake venom can stop bleeding and whether Gila monster venom
can treat diabetes. They also have developed a painkiller based
on the venom of a deadly sea snail.
Work with these proteins and molecules is the natural
progression from previous science studying simpler plant
extracts that have yielded key medicines, said Michael Egan,
president of Transmolecular Industries.
"Evolution has had this stuff for a while, so chances are
(animals) have a few things we can take advantage of," Egan
Giant yellow Israeli scorpions live in the deserts of the
Middle East and grow to about 4 inches long.