Abstract
Cell adhesion receptor integrin α(v)β(3) is a promising biomarker for developing tumor-angiogenesis targeted theranostics. In this study, we aimed to examine the therapeutic potential of peptide receptor radionuclide therapy (PRRT) with (188)Re-IDA-D-[c(RGDfK)](2) (11.1 MBq). The results showed that the tumor volume was significantly decreased by 81% compared with the vehicle-treated group in U87-MG xenografts. The quantitative in vivo anti-angiogenic responses of PRRT were obtained using (99m)Tc-IDA-D-[c(RGDfK)](2) SPECT and corresponded to the measured tumor volume. PRRT combined with temozolomide (TMZ) resulted in a 93% reduction in tumor volume, which was markedly greater than that of each agent used individually. In addition, histopathological characterization showed that PRRT combined with TMZ was superior to PRRT or TMZ alone, even when TMZ was used at half dose. Overall, our results indicated that integrin-targeted PRRT and TMZ combined therapy might be a new medical tool for the effective treatment of glioblastoma.