CHARACTERIZATION OF THERANOSTIC PEPTIDES FOR GLIOBLASTOMA MULTIFORME

Glioblastoma multiforme (GBM) is a type of primary CNS tumor in which viable treatment options do not exist. Standard of care including tumor resection, chemotherapy, and radiation does little to extend the 5-year survival expectancy past 5.1%. Herein, two small-peptide molecules with inherent antitumor activity, blood-brain barrier permeability, and capability for tumor-specific drug deliverance and intraoperative visualization (termed theranostic) were of focus. Confocal microscopy was employed to characterize in vitro specificity of chlorotoxin, a 4 kDa scorpion venom peptide, and rBSG, the recombinant 25 kDa non-glycosylated extracellular domain of extracellular matrix metalloproteinase inducer (EMMPRIN; Basigin) isoform 2, toward U87 GBM and MSU 1.1 human foreskin fibroblast cell line labelling. A novel cDNA construct coding a recombinant chlorotoxin (rCTX) variant for periplasmic prokaryotic expression and histidine-tag purification was created. However, prokaryotic expression and purification of histidine-tagged rCTX was not obtainable. Confocal data also supports variable labelling activity of commercially sourced CTX and rBSG in vitro for both U87 and MSU1.1 cell lines. These data support further investigation of small-peptide theranostics for GBM treatment