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Molecular Magnetic Resonance Imaging of Tumor Response to Therapy.

ABSTRACT: Personalized cancer medicine requires measurement of therapeutic efficacy as early as possible, which is optimally achieved by three-dimensional imaging given the heterogeneity of cancer. Magnetic resonance imaging (MRI) can obtain images of both anatomy and cellular responses, if acquired with a molecular imaging contrast agent. The poor sensitivity of MRI has limited the development of activatable molecular MR contrast agents. To overcome this limitation of molecular MRI, a novel implementation of our caspase-3-sensitive nanoaggregation MRI (C-SNAM) contrast agent is reported. C-SNAM is triggered to self-assemble into nanoparticles in apoptotic tumor cells, and effectively amplifies molecular level changes through nanoaggregation, enhancing tissue retention and spin-lattice relaxivity. At one-tenth the current clinical dose of contrast agent, and following a single imaging session, C-SNAM MRI accurately measured the response of tumors to either metronomic chemotherapy or radiation therapy, where the degree of signal enhancement is prognostic of long-term therapeutic efficacy. Importantly, C-SNAM is inert to immune activation, permitting radiation therapy monitoring.

SUBMITTER: Shuhendler AJ

PROVIDER: S-EPMC4594000 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Molecular Magnetic Resonance Imaging of Tumor Response to Therapy.

Shuhendler Adam J AJ Ye Deju D Brewer Kimberly D KD Bazalova-Carter Magdalena M Lee Kyung-Hyun KH Kempen Paul P Dane Wittrup K K Graves Edward E EE Rutt Brian B Rao Jianghong J

Scientific reports 20151006

Personalized cancer medicine requires measurement of therapeutic efficacy as early as possible, which is optimally achieved by three-dimensional imaging given the heterogeneity of cancer. Magnetic resonance imaging (MRI) can obtain images of both anatomy and cellular responses, if acquired with a molecular imaging contrast agent. The poor sensitivity of MRI has limited the development of activatable molecular MR contrast agents. To overcome this limitation of molecular MRI, a novel implementatio ...[more]

PMID: 26440059

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Molecular Magnetic Resonance Imaging of Tumor Response to Therapy.

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Molecular Magnetic Resonance Imaging of Tumor Response to Therapy.

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