A 36-residue scorpion peptide that homes to glioma cells and lit up the fluorescent 'tumor paint' concept.
Also known as: CTX · ClTx · tozuleristide · TM-601
Part of the Foundational & therapeutic peptides cluster
Overview
Chlorotoxin is a 36-amino-acid peptide from deathstalker scorpion venom, stabilized by four disulfide bonds. It binds targets enriched on glioma and other tumor cells, including matrix metalloproteinase-2 and small-conductance chloride channels, and has been developed into fluorescent conjugates ('tumor paint') to help surgeons see cancer margins. This page is educational and not medical advice.
Source & context
Biological / chemical source: Venom of the deathstalker scorpion (Leiurus quinquestriatus)
Primary research or clinical context: Research and imaging tool; investigational tumor-targeting agent ('tumor paint')
Tumor-homing peptide
Although first described as a chloride-channel blocker, chlorotoxin's practical interest comes from its selective binding to glioma cells over healthy brain tissue, linked to MMP-2 and related surface complexes. Its small, disulfide-locked scaffold is stable and tolerant of chemical conjugation, making it a versatile targeting ligand.
Imaging and research use
Chlorotoxin fused to dyes such as Cy5.5 forms intraoperative imaging agents studied to highlight tumor tissue, while a synthetic version (TM-601) and CAR-T targeting approaches have been explored in oncology research. It is used here as an educational example of venom-derived molecular tools, not as an approved therapy.
FAQ about Chlorotoxin
What is Chlorotoxin?+
Chlorotoxin is a 36-amino-acid peptide from deathstalker scorpion venom, stabilized by four disulfide bonds. It binds targets enriched on glioma and other tumor cells, including matrix metalloproteinase-2 and small-conductance chloride channels, and has been developed into fluorescent conjugates ('tumor paint') to help surgeons see cancer margins. This page is educational and not medical advice.
Is Chlorotoxin an approved medicine?+
Chlorotoxin is discussed here as a research / educational topic. Research and imaging tool; investigational tumor-targeting agent ('tumor paint'). This is not medical advice.
What is the typical length of Chlorotoxin?+
Chlorotoxin is commonly described as approximately 36 amino acids (Scorpion-venom peptide (toxin)).