Conjugation of Functionalized Gadolinium Metallofullerenes with IL-13 Peptides for Targeting and Imaging Glial Tumors

BACKGROUND: Glioblastoma multiforme is the most common and most lethal primary brain tumor in humans, with median survival of approximately 1 year. Owing to the ability of glioma cells to aggressively infiltrate normal brain tissue and survive exposure to current adjuvant therapies, there is a great need for specific targeted nanoplatforms capable of delivering both therapeutic and imaging agents directly to invasive tumor cells. METHOD: Gadolinium-containing endohedral fullerenes, highly efficient contrast agents for MRI, were functionalized and conjugated with a tumor-specific peptide and assessed for their ability to bind to glioma cells in vitro. RESULTS: We report the successful conjugation of the carboxyl functionalized metallofullerene Gd(3)N@C(80)(OH)(-26)(CH(2)CH(2)COOH)(-16) to IL-13 peptides and the successful targeting ability towards brain tumor cells that overexpress the IL-13 receptor (IL-13Rα2). CONCLUSION: These studies demonstrate that IL-13 peptide-conjugated gadolinium metallofullerenes could serve as a platform to deliver imaging and therapeutic agents to tumor cells.