Dataset Information

Magnetic Resonance Imaging of Macrophage Response to Radiation Therapy.

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.

SUBMITTER: Yang H

PROVIDER: S-EPMC10742077 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Publications

Magnetic Resonance Imaging of Macrophage Response to Radiation Therapy.

Yang Harrison H Howerton Brock B Brown Logan L Izumi Tadahide T Cheek Dennis D Brandon J Anthony JA Marti Francesc F Gedaly Roberto R Adatorwovor Reuben R Chapelin Fanny F

Cancers 20231217 24

<h4>Background</h4>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 (<sup>19</sup>F) 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 macro ...[more]

PMID: 38136418

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Dataset Information

Magnetic Resonance Imaging of Macrophage Response to Radiation Therapy.

Background

Methods

Results

Conclusion

Publications

Magnetic Resonance Imaging of Macrophage Response to Radiation Therapy.

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