{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T14:15:29Z","timestamp":1790864129551,"version":"4.1.0"},"reference-count":137,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,3,14]],"date-time":"2021-03-14T00:00:00Z","timestamp":1615680000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Radiation therapy is one of the main modalities to treat cancer\/tumor. The response to radiation therapy, however, can be influenced by physiological and\/or pathological conditions in the target tissues, especially by the low partial oxygen pressure and altered redox status in cancer\/tumor tissues. Visualizing such cancer\/tumor patho-physiological microenvironment would be a useful not only for planning radiotherapy but also to detect cancer\/tumor in an earlier stage. Tumor hypoxia could be sensed by positron emission tomography (PET), electron paramagnetic resonance (EPR) oxygen mapping, and in vivo dynamic nuclear polarization (DNP) MRI. Tissue oxygenation could be visualized on a real-time basis by blood oxygen level dependent (BOLD) and\/or tissue oxygen level dependent (TOLD) MRI signal. EPR imaging (EPRI) and\/or T1-weighted MRI techniques can visualize tissue redox status non-invasively based on paramagnetic and diamagnetic conversions of nitroxyl radical contrast agent. 13C-DNP MRI can visualize glycometabolism of tumor\/cancer tissues. Accurate co-registration of those multimodal images could make mechanisms of drug and\/or relation of resulted biological effects clear. A multimodal instrument, such as PET-MRI, may have another possibility to link multiple functions. Functional imaging techniques individually developed to date have been converged on the concept of theranostics.<\/jats:p>","DOI":"10.3390\/molecules26061614","type":"journal-article","created":{"date-parts":[[2021,3,14]],"date-time":"2021-03-14T23:52:06Z","timestamp":1615765926000},"page":"1614","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Multimodal Functional Imaging for Cancer\/Tumor Microenvironments Based on MRI, EPRI, and PET"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8151-4067","authenticated-orcid":false,"given":"Ken-ichiro","family":"Matsumoto","sequence":"first","affiliation":[{"name":"Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Quantum Medical Science Directorate, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James B.","family":"Mitchell","sequence":"additional","affiliation":[{"name":"Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1002, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Murali C.","family":"Krishna","sequence":"additional","affiliation":[{"name":"Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1002, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.radonc.2019.03.028","article-title":"An integrated physico-chemical approach for explaining the differential impact of FLASH versus conventional dose rate irradiation on cancer and normal tissue responses","volume":"139","author":"Spitz","year":"2019","journal-title":"Radiother. 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