Abstract

Theranostic Gold-198 Nanoparticles In Nanomedicine: Implications In Concurrent Molecular Imaging and Tumor Therapy

Kattesh V. Katti, Director, Institute of Green Nanotechnology / Radiology / Cancer Nanotechnology Platform, University of Missouri

We envisioned that radioactive gold nanoparticles, which are inherently theranostic, will present realistic prospects for the development of concurrent molecular imaging and therapeutic agents. Nanosized gold-198-based theranostic agents are important in achieving optimal therapeutic payloads in prostate and other solid tumors because of their (i) size; (ii) inherent affinity toward tumor vasculature and (iii) most importantly through their favorable radiochemical properties. 198Au provides a desirable beta energy emission and half-life that destroys tumor cells/tumor tissue (betamax = 0.96 MeV; half-life of 2.7 days. Its penetration range (up to 11 mm in tissue or up to 1100 cell diameters) is sufficiently long to provide cross-fire effects to destroy prostate tumor cells, but short enough to minimize radiation exposure to tissues near the capsule periphery. In this lecture, I will present (1) synthesis and complete characterization of Laminin receptor specific EGCg functionalized radioactive gold nanoparticles; (ii) evidence of endocytosis due to Laminin receptors on prostate tumor cells and quantitative estimation of AuNP-EGCg within PC-3 cells using neutron activation analysis (NAA) (ii) experimental results on the theranostic applications of Au-198 prostate tumor specific AuNP-EGCg through in vivo studies in mice and tumor bearing dogs; and (iv) therapeutic efficacy studies of 198AuNP-EGCg in prostate tumor bearing mice and dogs, demonstrating excellent tumor retention resulting in over 85% inhibition of tumor growth through singular intratumoral injection. The overall oncological implications of this and a range of new nano theranostic agents in treating human prostate and various other solid tumors will also be discussed.