A neurotoxin with potential anticancer property. Chlorotoxin (CTX) is a 36-amino acid peptide found in the venom of the deathstalker scorpion, and a chloride channel blocker. This toxin binds preferentially to glioma cells via the transmembrane endopeptidase matrix metalloproteinase-2 (MMP-2), and thereby prevents the spread of tumor cells. MMP-2 is specifically up-regulated in gliomas and related cancers, but is not normally expressed in brain.

A substance being studied in the diagnosis and treatment of glioma (a type of brain cancer) and other types of cancer. It binds to cancer cells in the brain and peripheral nervous system and may keep them from spreading. Chlorotoxin comes from the venom of a type of scorpion. A form of chlorotoxin made in the laboratory is called TM-601. Chlorotoxin is a type of neurotoxin.