1: NMR Biomed. 2004 Aug;17(5):240-62. 

Assessment of tumor oxygenation by electron paramagnetic resonance: principles
and applications.

Gallez B, Baudelet C, Jordan BF.

Biomedical Magnetic Resonance Unit and Laboratory of Medicinal Chemistry and
Radiopharmacy, Universite Catholique de Louvain, Brussels, Belgium.
Gallez@cmfa.ucl.ac.be

This review paper attempts to provide an overview of the principles and
techniques that are often termed electron paramagnetic resonance (EPR) oximetry.
The paper discusses the potential of such methods and illustrates they have been
successfully applied to measure oxygen tension, an essential parameter of the
tumor microenvironment. To help the reader understand the motivation for
carrying out these measurements, the importance of tumor hypoxia is first
discussed: the basic issues of why a tumor is hypoxic, why these hypoxic
microenvironments promote processes driving malignant progression and why
hypoxia dramatically influences the response of tumors to cytotoxic treatments
will be explained. The different methods that have been used to estimate the
oxygenation in tumors will be reviewed. To introduce the basics of EPR oximetry,
the specificity of in vivo EPR will be discussed by comparing this technique
with NMR and MRI. The different types of paramagnetic oxygen sensors will be
presented, as well as the methods for recording the information (EPR
spectroscopy, EPR imaging, dynamic nuclear polarization). Several applications
of EPR for characterizing tumor oxygenation will be illustrated, with a special
emphasis on pharmacological interventions that modulate the tumor
microenvironment. Finally, the challenges for transposing the method into the
clinic will also be discussed. Copyright 2004 John Wiley & Sons, Ltd.

PMID: 15366026 [PubMed - in process]