Abstract
Background: Magnetic resonance imaging (MRI) is a non-invasive imaging modality which, in conjunction with biopsies, provide a qualitative assessment of tumor response to treatment. Intravenous injection of contrast agents such as fluorine (19F) nanoemulsions labels systemic macrophages, which can, then, be tracked in real time with MRI. This method can provide quantifiable insights into the behavior of tumor-associated macrophages (TAMs) in the tumor microenvironment and macrophage recruitment during therapy.
Methods: Female mice received mammary fat pad injections of murine breast or colon cancer cell lines. The mice then received an intravenous 19F nanoemulsion injection, followed by a baseline 19F MRI. For each cancer model, half of the mice then received 8 Gy of localized radiation therapy (RT), while others remained untreated. The mice were monitored for two weeks for tumor growth and 9F signal using MRI.
Results: Across both cohorts, the RT-treated groups presented significant tumor growth reduction or arrest, contrary to the untreated groups. Similarly, the fluorine signal in treated groups increased significantly as early as four days post therapy. The fluorine signal change correlated to tumor volumes irrespective of time.
Conclusion: These results demonstrate the potential of 19F MRI to non-invasively track macrophages during radiation therapy and its prognostic value with regard to tumor growth.
Document Type
Article
Publication Date
12-2023
Digital Object Identifier (DOI)
https://doi.org/10.3390/cancers15245874
Funding Information
This publication was supported by the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through grant UL1TR001998, by grant # IRG-19-140-31 from the American Cancer Society, and by the Shared Resource Facilities of the University of Kentucky Markey Cancer Center P20CA177558. H. Y. received support from the Commonwealth Undergraduate Research Experience (CURE) Fellowship for this project. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Repository Citation
Yang, Harrison; Howerton, Brock; Brown, Logan; Izumi, Tadahide; Cheek, Dennis C.; Brandon, Jason Anthony; Marti, Francesc; Gedaly, Roberto; Adatorwovor, Reuben; and Chapelin, Fanny, "Magnetic Resonance Imaging of Macrophage Response to Radiation Therapy" (2023). Markey Cancer Center Faculty Publications. 363.
https://uknowledge.uky.edu/markey_facpub/363
Notes/Citation Information
© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).