Recent literatures found that chlorotoxin could specifically block the chlorotoxin-sensitive chloride ion channels and/or bind to matrix metalloproteinase 2 (MMP-2) in positive tumor cells, which are overexpressed in the glioma, but they were absent or express in low abundance in healthy tissues or in tumors of nonglial origin [17–21]. This evidence concerns the gene MMP2 and glioma.