Scorpion Venom Is Used to Fight Cancer in 'Tumor Paint'
Researchers looking at other poisonous insects to find new treatments.
Nov. 30, 2013 — -- Seattle researchers have developed a new technology that they say utilizes scorpion venom to help surgeons find and remove dangerous brain cancer cells.
The technology, called "tumor paint," was developed by Dr. Jim Olson, a brain cancer specialist at Seattle Children's Hosptial and a professor at the Fred Hutchinson Cancer Research Center in Seattle.
"Scorpions have been evolving over millions of years to make a drug that can get into the brain and paralyze the victim," Olson said during a lecture at the PopTech convention last month.
The "tumor paint" is created by utilizing a protein derived from the paralyzing venom of an Israeli deathstalker scorpion. The re-engineered protein, which binds to cancer cells, is then joined with a fluorescent molecule "flashlight" that has been used safely in human surgeries for decades.
"The scorpion toxin finds the cancer cells and drags the flashlight into them and makes them glow brilliantly," Olson said at the convention.
According to Olson, "tumor paint" has been used to successfully to identify cancer cells in dogs and mice during pre-clinical trials.
Olson says in some cases the paint was able to identify extremely small amounts of cancer cells, sometimes just a few hundred cells that would be nearly impossible to identify otherwise.
Human trials for "tumor paint" are slated to start in Australia this month and if they are successful, a second round of trials would start in the U.S. in six to nine months.
"It's really hard to get molecules into the brain due to the blood-brain barrier," Olson told ABCNews.com, describing the membrane around blood vessels in the brain designed to keep out toxins. "Most drugs that are made by the drug companies can't penetrate that barrier. The scorpion has found a way to get these proteins in the brain."
Olson said one major benefit for brain surgeons is that they could use the "tumor paint" in real time during a surgery, rather than using an MRI image as a road map when performing brain surgery.
"[The MRI's] hanging up on the wall, the patient's [brain material] is being moved, everything is changing," said Olson of the difficulties in using MRIs during brain surgery.
While "tumor paint" was originally developed to treat brain tumors, Olson said they have found that the paint has also been able to highlight breast, colon and skin tumors as well.
For Olson, helping to create "tumor paint" was just the start of a much larger project. Inspired by his success with the scorpion protein, Olson, who sees patients at Seattle Children's Hospital, redeveloped his research lab to focus solely on studying proteins derived from nature.
Now called the Project Violet lab, after one of Olson's pediatric patients who died of a brain tumor, the lab focuses on finding and re-engineering other nature-based proteins that could be used in medical treatments.
"Nature has found ways to get these molecules into places in the body that it's really hard to get medicine into," said Olson.
In addition to focusing on proteins derived from nature, Olson's lab based at the Fred Hutchinson Cancer Center is different from many other labs since the public is encouraged to be involved.
People can go the Project Violet website and "adopt" a molecule for $100. By adopting a molecule, a person selects the type of cell and protein they want joined, effectively creating a new molecule for study. The fee goes toward the creation of that molecule, which the lab will then study to see if it can be used in medical treatments.
While "tumor paint" took at least a decade to develop, Olson said he and his research team are inspired every day by the young children he works with at the hospital.
"When you're taking care of kids with cancer you say, 'How can we change the world for them?' And you put all other considerations aside," said Olson. "Honestly, a barrier comes up every day and every week; these kids motivate us."