Distributions of Intravenous Injected Iodine Nanoparticles in Orthotopic U87 Human Glioma Xenografts Over Time and Tumor Therapy

Abstract

Aim: To analyze the localization, distribution and effect of iodine nanoparticles (INPs) on radiation therapy (RT) in advanced intracerebral gliomas over time after intravenous injection. Materials & methods: Luciferase/td-tomato expressing U87 human glioma cells were implanted into mice which were injected intravenously with INPs. Mice with gliomas were followed for tumor progression and survival. Immune-stained mouse brain sections were examined and quantified by confocal fluorescence microscopy. Results: INPs injected intravenously 3 days prior to RT, compared with 1 day, showed greater association with CD31-staining structures, accumulated inside tumor cells more, covered more of the tumor cell surface and trended toward increased median survival. Conclusion: INP persistence and redistribution in tumors over time may enable greater RT enhancement and clinically relevant hypo-fractionated-RT and may enhance INP efficacy.

Iodine nanoparticle radiotherapy of human breast cancer growing in the brains of athymic mice

“…We have shown in a separate study that INP-RT is more effective than RT for fractionated RT comparing two doses of 10 Gy (one day apart) versus a single RT dose of 20 Gy. While the single 20 Gy RT dose provided greater life extension than two fractions, in both cases INP-RT was more effective than RT-only 40 . Also, the observation that the iodine in the INPs does not wash out from the tumor in at least three days 7 appears promising for hypofractionation protocols now being used where the dose is delivered in one week 48 since the INPs would not require multiple dosing.…”

“…The irradiation was done at 24 h to be consistent and for comparison with our previous experiments 7 . However, it is predicted that the results would be better if irradiated at 3 days, and preliminary data supports this 40 . Times less than 24 h were not studied here since uptake in gliomas showed lower tumor uptake at earlier times 40 .…”

“…Further studies addressing this connection have shown that the heavy atom nanoparticle needs to be close to the nucleus 38 or other sensitive targets such as mitochondria 39 . A confocal microlocalization study of the INPs indeed shows the INPs are close to many tumor nuclei 40 .…”

Folic acid‐decorated astrocytes‐derived exosomes enhanced the effect of temozolomide against glioma

“…The orthotopic U‐87 mouse model was established in female NCG (NOD/ShiLtJGpt‐Prkdc em26 Il2rg em26 /Gpt) mice (Jicuiyaokang, Jiangsu, China). U‐87 cells (1 × 10 6 cells) were suspended in PBS (1 μL) and implanted into mice brainstem as previously described operation steps 25 . After a 6‐day cellular implantation, mice were randomly assigned into four groups ( n = 6) and treated with PBS, TMZ, TMZ@Astro‐exo, or TMZ@Astro‐exo‐FA (5 mg/kg) to evaluate the therapeutic efficacy via the tail vein.…”

“…(1 μL) and implanted into mice brainstem as previously described operation steps. 25 After a 6-day cellular implantation, mice were randomly assigned into four groups (n = 6) and treated with PBS, TMZ, TMZ@Astro-exo, or TMZ@Astro-exo-FA (5 mg/kg) to evaluate the therapeutic efficacy via the tail vein. The treatment was repeated every 3 days for a total of four doses.…”