Posted: December 15, 2014
Positron emission tomography (PET) is a non-invasive nuclear medicine imaging technique that produces a three-dimensional image of physiological processes and tissue micro environments, which is used for diagnosing and/or treating diseases including cancer, heart disease, and brain abnormalities. Traditionally, tumour imaging with PET relies on the use of the glucose analogue 2-deoxy-2-[18F]fluoro-D-glucose([18F]FDG) as the imaging agent, which takes advantage of the characteristic over expression of GLUT1 (a member of the family of facilitative hexose transport proteins known as GLUTs) in many cancerous cells.
Unfortunately, [18F]FDG-PET is ineffective in the detection of small tumours and more differentiated subtypes, accumulates in areas of inflammation (due to the large uptake of [18F]FDG by immune cells), and therefore, generates false-positives, or poor resolution images in PET . Additionally, certain tumoursdemonstrate low expression of GLUT1, and thus false-negatives may be observed due to low concentrations of [18F]FDG entering these cancerous cells.
In breast cancer, the glucose/fructose transporter GLUT2 and the fructose transporter GLUT5 have been shown to be over expressed in many breast tumours, suggesting that fructose-based analogues would be useful for the improved imaging of breast cancer. Dr. Chris Cheeseman and colleagues at the University ofAlberta have recently designed and synthesized a new class of fluorinated fructose compounds. Such fructose-based radio pharmaceuticals have the potential to be used during in vivo PET imaging of breast cancer. One such compound, 6-deoxy-6-fluoro-D-fructose (6FDF), has been shown to be transported in vitro into two human, GLUT5 expressing breast cancer cell lines. Early in vivo trials using a GLUT 5 expressing murine breast cancer model have had promising results, with flank implanted tumours readily taking up [18F]6FDF.
6FDF radio pharmaceuticals may provide the following advantages:
- Enhanced sensitivity and specificity to small tumors and more differentiated sub-types such as tubular carcinomas or lobular carcinomas, which will generate more accurate and reliable 3D images.
- Improved image resolution with clear distinction of tumoral cells from surrounding inflammation, which would enable more accurate monitoring of treatment efficacy.
- Interactivity allowing varying lightning conditions.
- Ability to image GLUT5 expressing, [18F]FDG-PET invisible tumors.
Companies interested in diagnostic imaging of cancer cells and non-imaging tracer studies.
US 8,293,208 & US 8,501,154
Technology Management Group
TEC Edmonton – University of Alberta