Hypoxic Radiosensitizer-Lipid Coated Gold Nanoparticles Enhance the Effects of Radiation Therapy on Tumor Growth.

Radiotherapy (RT) has become one of the most effective treatments for malignant tumor. Intra-tumoral hypoxia is recognized as a chief reason that induces resistance to radiation. Moreover, the toxicities of RT to normal tissues limits the usage of high doses of radiation to eliminate cancer cells. Therefore, developing an effective radiosensitizer is critical for improving the curative effects of RT. In the present study, we developed angiopep-2 (A2) modified hypoxic lipid radiosensitizer (HLR) coated gold nanoparticles (GNPs) (referred to as A2-HRGNPs) to increase the RT sensitivity of tumors. The A2-HRGNPs are comprised of the following two functional components: (1) HLR enhances the RT sensitivity on hypoxic tumor cells; (2) alkylthiol modified GNPs (DGNPs) increase radiation effects by a dose enhancing effect in RT. Our findings suggest that the synergistic radiosensitizing effects of A2-HRGNPs can significantly enhance radiosensitization effects and thus, inhibit tumor growth in vivo.