Gd3+-DTPA-DG: novel nanosized dual anticancer and molecular imaging agent

Background: Difficulties in the use, preparation, and cost of radioactively-labeled glycosylated compounds led to this research and development study of a new gadolinium-labeled glucose compound that does not have a radioactive half-life or difficulties in its synthesis and utilization. Methods: Based on the structure of the 2-fluoro-2-deoxy-D-glucose molecule ((18)FDG), a new compound consisting of D-glucose (1.1 nm) conjugated to a well-known chelator, diethylenetriamine penta-acetic acid (DTPA), was synthesized, labeled with Gd3+, and examined in vitro and in vivo. Results: This novel compound not only demonstrated excellent and less costly imaging capability, but also showed anticancer effects on treated cells. Our results demonstrated that the new Gd3+-DTPA-DG compound (GDD, with GDD conjugate aggregation of about 8 nm at 0.02 mg/mL concentration) significantly decreased HT1080 and HT29 tumor cell numbers. Application of GDD to cancer cells also increased levels of tumor necrosis factor alpha, but did not alter blood glucose levels. Interestingly, no toxicological findings were seen in normal human kidney cells. Conclusion: Dual application of GDD for both imaging and treatment of tumor cells could be remarkably advantageous in both the diagnosis and treatment of cancer.