Distinguished iNANO Lecture: Hyperpolarized MR

Professor Jan Henrik Ardenkjær-Larsen, Center for Magnetic Resonance, Technical University of Denmark, DK

Hyperpolarized MR

Hyperpolarized Magnetic Resonance is a new medical imaging modality that offers exceptional possibilities to follow changes in metabolism¹. The method is enabled by a more than 10,000 fold enhancement² of the signal from tracer molecules that probe central metabolic pathways.

The tracer goes through an “activation step”, hyperpolarization, before it is injected intravenously into the patient. The tracer circulates by the vasculature to the tissue of interest, where it is taken up by the tissue cells and metabolized into specific products. MR is unique in several ways: 1) it already provides anatomical and morphological images with high resolution and contrast based on the tissue water protons, 2) it is does not expose the patient to any ionizing radiation, and 3) it is a spectroscopic method that quantifies the metabolites individually. With hyperpolarization, we are now able to follow the metabolism of the tracer in real-time.

The first tracer in clinical development is ¹³C-pyruvate. Pyruvate is at a pivotal point in glycolysis and allows us to probe directly the Warburg effect through the elevated lactate-to-pyruvate ratio. The hope is that more accurate diagnosis and staging can be made, and that the method will provide an early read-out of response to treatment. The first clinical studies^3–6 have been performed with encouraging results, e.g. aggressiveness staging of prostate cancer. In this talk, I will review the technology and discuss the applications and prospects.

References

1. Kurhanewicz, J. et al. Hyperpolarized 13C MRI: Path to Clinical Translation in Oncology. Neoplasia 21, 1–16 (2019).
2. Ardenkjær-Larsen, J. H. et al. Increase in signal-to-noise ratio of > 10,000 times in liquid-state NMR. Proc. Natl. Acad. Sci. U. S. A. 100, 10158–63 (2003).
3. Nelson, S. J. et al. Metabolic Imaging of Patients with Prostate Cancer Using Hyperpolarized [1-13C]Pyruvate. Sci. Transl. Med. 5, 198ra108-198ra108 (2013).
4. Cunningham, C. H. et al. Hyperpolarized 13C Metabolic MRI of the Human Heart: Initial Experience. Circ. Res. CIRCRESAHA.116.309769- (2016). doi:10.1161/CIRCRESAHA.116.309769
5. Aggarwal, R., Vigneron, D. B. & Kurhanewicz, J. Hyperpolarized 1-[13C]-Pyruvate Magnetic Resonance Imaging Detects an Early Metabolic Response to Androgen Ablation Therapy in Prostate Cancer. Eur. Urol. 72, 1028–1029 (2017).
6. Miloushev, V. Z. et al. Metabolic Imaging of the Human Brain with Hyperpolarized 13C Pyruvate Demonstrates 13C Lactate Production in Brain Tumor Patients. Cancer Res. (2018). doi:10.1158/0008-5472.CAN-18-0221.
   
   

Host: Associate Professor Frans Mulder, iNANO & Department of Chemistry, AU

Coffee, tea and bread will be served from 10:00 in front of iNANO AUD