Molecular imaging of tumor invasion and metastases: the role of MRI.

Abstract

The processes of tumor invasion and metastasis have been well characterized at the molecular level, and numerous biomarkers of tumor aggressiveness have been discovered. Molecular imaging offers the opportunity to depict specific cell markers relevant to tumor aggressiveness. Here, we describe the role of MRI in identifying tumor invasiveness and metastasis with reference to other methods. Target-specific molecular imaging probes for tumor invasiveness have been developed for positron emission tomography and optical imaging, but progress in MRI has been slower. For example, proteases associated with tumor invasion, such as specific matrix metalloproteinases or cathepsins, can be targeted in vivo using optical and positron emission tomography methods, but have not yet been successful with MRI. In addition, we describe the use of MRI to detect metastases. Novel MR contrast agents based on iron oxide and dendrimer nanomaterials allow for better characterization of tumor metastases. Organ-specific MR contrast agents are used to identify metastatic disease in the liver. Finally, diffusion-weighted whole-body MRI is discussed as an alternative offered by MRI that does not require the use of molecular probes to screen distant metastases.

• Authors: Thomas E McCann, Nobuyuki Kosaka, Baris Turkbey, Makoto Mitsunaga, Peter L Choyke, Hisataka Kobayashi
• Journal: NMR in biomedicine (NMR Biomed) Vol. 24 Issue 6 Pg. 561-8 (Jul 2011) ISSN: 1099-1492 [Electronic] England
• PMID: 21793070 (Publication Type: Journal Article, Research Support, N.I.H., Intramural, Review)
• Copyright: Published in 2010 by John Wiley & Sons, Ltd.

Chemical References

• Molecular Probes

Topics

• Animals
• Diffusion Magnetic Resonance Imaging
• Humans
• Magnetic Resonance Imaging (methods)
• Molecular Imaging (methods)
• Molecular Probes (metabolism)
• Neoplasm Invasiveness (diagnosis)
• Neoplasm Metastasis (diagnosis)