Owing to the high specificity and selectivity for glioma cells that overexpress MMP2, the synthetic version of CTX (designated, TM-601) has been used in clinical imaging and therapy of malignant glioma tumors, as exemplified by I131-iodination of the Tyr residue of the peptide, which produces I131-TM-601 used in radiodiagnostics and radiotherapy [92]. Here, MMP2 is linked to glioma.