Illuminating Brain Tumours With Scorpion Toxins Could Save Lives

Up until now, removing brain tumours has been a fairly imprecise — and thus highly dangerous — art. Cancerous tissue in the brain looks almost exactly like healthy tissue, and being just one millimetre off is enough to permanently affect a patient’s quality of life.

Plus, it’s almost impossible to tell if any post-surgery neurological damage is from the tumour or the surgery itself. Jim Olson, a paediatric neuro-oncologist, looked to an unlikely source to solve the problem: scorpion toxins.

For reasons still not fully understood, injected toxins from a scorpion’s sting will only bind to cancerous tissue and, as an added bonus, have the relatively rare ability to cross the blood-brain barrier. By creating a synthetic version of this toxin and binding it to molecules that glow in near-infrared light, tumours can be set aglow and, hopefully, save a lot of healthy brain tissue in the process. With a glowing tumour, surgeons would finally be able to identify cancerous cells with relative ease, making it far easier to avoid healthy tissue.

Successful tests have already been run in which a mouse playing host to a human tumour had the “tumour paint” into its tail. Within 20 minutes, the cancerous tumour began to glow, setting it apart from the rest of the mouse’s body. Even though it originated as a venom, researchers say the toxin “seems to be safe.” While not exactly a winning endorsement, the life-saving potential is overwhelming with human trials should beginning sometime in late 2013.


Picture: Shuttershock, Arnoud Quanjer
