Clinically Translatable Phosphonated Silica Microspheres for Selective Internal Radiation Therapy of Hepatocellular Carcinoma

Abstract

Selective internal radiation therapy (SIRT) is used as a locoregional therapy for hepatocellular carcinoma (HCC) to delay the progression of HCC. Thus far, various kinds of radioactive microspheres with different materials and radionuclides have been developed to be utilized in SIRT, but they remain unsatisfactory in some ways. Herein, using a facile method, phosphonated silica microspheres (PSMs) are prepared and further radiolabeled with 177Lu in a rapid and effective manner. The results suggest that the radiolabeling efficiency is higher than 99%, and the specific activity of the product is 10 kBq per microsphere. 177Lu-PSM exhibits outstanding in vivo radiolabeling stability, excellent antitumor activity, and single-photon-emission computed tomography–computed tomography (SPECT/CT) imaging capability. In addition, it is shown that PSM can be produced in large quantities at a relatively low cost. The results indicate that 177Lu-PSM might hold considerable potential for translation to clinical applications.