When pediatric oncologist Dr. Jim Olson began practicing medicine, he was consumed by a single question: Could it be possible to light up cancer cells? Flash forward more than two decades, and he’s developed a product that can do just that: a glowing ‘tumor paint’ derived from scorpion venom.
The Israeli deathstalker scorpion (Leiurus quinquestriatus) has more in its wheelhouse than a name that’s metal AF. This tiny sand-skimmer packs one of the most potent concoctions of neurotoxins of any scorpion species, and one of its peptides, a tough ‘mini-protein’ known as Chlorotoxin, actually targets cancer cells.
“[It] binds to cancer cells but not to normal tissues – we still don’t fully understand why,” explains Olson. “What we did is we attached a little molecular ‘flashlight’ to that. So when the scorpion toxin finds the cancer cells, it injects the flashlight into them and they glow brilliantly.”
There’s a reason we say things like “This isn’t brain surgery.” When it comes to operating on our most important organs, a tiny mistake could mean the difference between recovery and death. “The key to brain surgery is to remove the bad stuff and leave the good stuff inside,” says University of Washington Neurological Sciences chair Dr Richard G Ellenbogen. “Well that all seems pretty straight forward … however, it’s not that easy. Inside the brain it can be very difficult to determine normal brain tissue and cancer. If you’re a millimeter off, or take a few grams of tissue that belonged safely in the brain, the patients wake up not as perfect as they went in.”
“…It was just one of those moments …Wow, this works.”
Olson hopes his tumor paint, which is being commercially developed by the team at Blaze Bioscience, will help to change that. “Our hope is that ten years from now, we’ll look back and say ‘I can’t believe we operated on tumors with just our eyes, and our fingers, and our thumbs,” he says.
When the chemical is injected into a brain cancer patient’s blood stream, for example, it travels up the veins and across the blood-brain barrier, a security system that keeps precious brain tissue out of harm’s way, while letting nutrients pass through. In other words, Brain Gandalf. Once through, the tumor paint settles on groups of cancer cells, where it can be excited by near-infrared light.
After trials on mice and dogs showed promising results, Blaze Bioscience won approval to begin human trials, which are still being conducted at Cedars Sinai Medical Center in Los Angeles. “The first case we did was a deep tumor,” clinical trial surgeon Dr Chirag Patil, told NPR. “When we took that first piece out and we put it on the table, the question was, ‘Does it glow?’ And when we saw that it [did], it was just one of those moments …Wow, this works.”
Patil has since successfully used tumor paint on six of his patients, and while this is definitely not an alternative to cancer prevention, Olson feels optimistic that the method will help surgeons remove tumors and, even more importantly, result in a better outcome for cancer patients in the future.
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IMAGES: Daniela Hartmann, Matt Reinbold, Jim Olson/Blaze Biosciece
