Scorpion venom is not a single substance. It is a mixture of dozens of peptides, many of which act on ion channels in nerve and muscle cells. In the deathstalker this cocktail is unusually potent, and envenomation can cause severe pain, autonomic disturbance and, in vulnerable people, life-threatening complications.
One component, a 36-amino-acid peptide named chlorotoxin, turned out to bind selectively to glioma cells and certain other tumour tissues rather than healthy brain. Researchers linked it to a fluorescent dye to make a compound often described as tumour paint, intended to show surgeons where a tumour ends and normal tissue begins. Derived agents have been carried into human clinical trials.
What this does not mean is that scorpion venom cures cancer. The peptide is a targeting label, not a treatment, and the value lies in seeing tumour boundaries more clearly. The precise molecular target of chlorotoxin has been debated, with matrix metalloproteinase-2 and annexin A2 among the proposed binding partners.