Technologies

Background

Positron emission tomography (PET) is a non-invasive nuclear medicine imaging technique that produces a three-dimensional image of physiological processes and tissue microenvironments, 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 overexpression 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 tumours demonstrate low expression of GLUT1, and thus false-negatives may be observed due to low concentrations of [18F]FDG entering these cancerous cells.

Description

In breast cancer, the glucose/fructose transporter GLUT2 and the fructose transporter GLUT5 have been shown to be overexpressed 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 of Alberta have recently designed and synthesized a new class of fluorinated fructose compounds. Such fructose-based radiopharmaceuticals 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.