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CEST theranostics: label-free MR imaging of anticancer drugs.

ABSTRACT: Image-guided drug delivery is of great clinical interest. Here, we explored a direct way, namely CEST theranostics, to detect diamagnetic anticancer drugs simply through their inherent Chemical Exchange Saturation Transfer (CEST) MRI signal, and demonstrated its application in image-guided drug delivery of nanoparticulate chemotherapeutics. We first screened 22 chemotherapeutic agents and characterized the CEST properties of representative agents and natural analogs in three major categories, i.e., pyrimidine analogs, purine analogs, and antifolates, with respect to chemical structures. Utilizing the inherent CEST MRI signal of gemcitabine, a widely used anticancer drug, the tumor uptake of the i.v.-injected, drug-loaded liposomes was successfully detected in CT26 mouse tumors. Such label-free CEST MRI theranostics provides a new imaging means, potentially with an immediate clinical impact, to monitor the drug delivery in cancer.

SUBMITTER: Li Y

PROVIDER: S-EPMC4872720 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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CEST theranostics: label-free MR imaging of anticancer drugs.

Li Yuguo Y Chen Hanwei H Xu Jiadi J Yadav Nirbhay N NN Chan Kannie W Y KW Luo Liangping L McMahon Michael T MT Vogelstein Bert B van Zijl Peter C M PC Zhou Shibin S Liu Guanshu G

Oncotarget 20160201 6

Image-guided drug delivery is of great clinical interest. Here, we explored a direct way, namely CEST theranostics, to detect diamagnetic anticancer drugs simply through their inherent Chemical Exchange Saturation Transfer (CEST) MRI signal, and demonstrated its application in image-guided drug delivery of nanoparticulate chemotherapeutics. We first screened 22 chemotherapeutic agents and characterized the CEST properties of representative agents and natural analogs in three major categories, i. ...[more]

PMID: 26837220

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