Figure 6.

Radionuclide therapy of U87MG tumor with [⁶⁴Cu]DPA. (A) BALB/c nude mice inoculated with 1 × 10⁶ cells received an intravenous injection of either [⁶⁴Cu]DPA (⁓3 mCi in 200 μL saline) or an equivalent of saline on day 6. (B) Tumor growth curves of mice treated with either saline (control) or [⁶⁴Cu]DPA. n = 6 mice for control and n = 5 mice for [⁶⁴Cu]DPA. Data are mean ± SEM. P value was calculated using two-way ANOVA. (C) Survival curves of U87MG tumor-bearing BALB/c nude mice treated with saline or [⁶⁴Cu]DPA. n = 6 mice for control and n = 5 mice for [⁶⁴Cu]DPA. Significance was assessed using the log-rank test. (D) Changes in body weight of U87MG tumor-bearing BALB/c nude mice treated with saline or [⁶⁴Cu]DPA. n = 4 mice. (E) PET-CT images of BALB/c nude mice bearing U87MG tumor. Mice were imaged at 4 and 18 h after intravenous injection of [⁶⁴Cu]DPA. MIP PET-CT images are shown. Yellow dashed circles indicate the tumor positions (left hind legs). (F) and (G) Whole-section H&E staining of U87MG from BALB/c nude mice (left panel). The tumor tissues were harvested on day 23 from mice treated with saline or [⁶⁴Cu]DPA. Scale bar, 1000 μm. An enlarged view of selected areas was shown at the right panels. Scale bar, 100 μm. (H) Immunohistochemical staining of Ki67 and PCNA in U87MG tumors. The tumor tissues were harvested on day 23 from mice treated with saline or [⁶⁴Cu]DPA. Scale bar: 200 μm.