Rheal A. Towner1, Nataliya Smith1, Debra Saunders1, Patricia Coutinho De Souza1, Leah Henry1, Florea Lupu2, Robert Silasi-Mansat2, Marilyn I. Ehrenshaft3, Ronald P. Mason3, Sandra E. Gomez-Mejiba4, Dario C. Ramirez4
1Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States; 2Cariovascular Biology, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States; 3Laboratory of Pharmacology & Chemistry, National Institute of Environmental Health Sciences, Research Triangle Park, NC, United States; 4Laboratory of Experimental Medicine & Therapeutics, National University of San Luis, San Luis, Argentina
Free radicals associated with oxidative stress play a major role in cancer. By combining immuno-spin-trapping (IST) and targeted molecular magnetic resonance imaging (mMRI), we detected in vivo levels of membrane-bound radicals (MBR) within tumors of GL261 glioma-bearing mice. The spin trapping agent DMPO (5,5-dimethyl pyrroline N-oxide) traps MBR which can be detected in vivo with a targeted molecular MRI probe that detects DMPO-trapped-MBR. This is the first report regarding the detection of in vivo levels of MBR from a glioma model. This novel non-invasive method can be applied to investigate free radical mechanisms in the pathogenesis of various cancers.