Expression and function of hexose transporters GLUT1, GLUT2, and GLUT5 in breast cancer-effects of hypoxia.

Abstract

Elevated growth in breast cancer (BC) activates hypoxia-inducible factor (HIF1α) and downstream, facilitative glucose transporter 1 (GLUT1), which can be visualized with 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG). GLUT5 (fructose) and GLUT2 (glucose/fructose) might provide alternative targets for BC imaging as to why effects of hypoxia on GLUT1/2/5 levels and function were examined in human BC models. GLUT1/2/5 and HIF1α mRNA was analyzed in BC patient biopsies. In MCF10A, MCF7, and MDA-MB231 cells, [18F]FDG, 6-deoxy-6-[18F]fluoro-d-fructose (6-[18F]FDF) and [18F]-fluoroazomycin arabinoside were used in radiotracer experiments, whereas GLUT1/2/5 mRNA was analyzed with real-time PCR and protein levels determined via Western blot/immunohistochemistry. Positron emission tomography imaging was performed in MCF7 and MDA-MB231 tumor-bearing mice. Glucose/fructose/cytochalasin B reduced cellular 6-[18F]FDF uptake by 50%, indicating functional involvement of GLUT2. With GLUT5 staining lower than GLUT1, 6-[18F]FDF revealed lower uptake than [18F]FDG [standardized uptake value (SUV)6-[18F]FDF, 120 min 0.77 ± 0.06 vs. SUV[18F]FDG, 120 min 1.08 ± 0.07] in MDA-MB231 tumors and was blocked by 20% with cytochalasin B after 10 min. Whereas correspondence between 6-[18F]FDF uptake and GLUT5 protein was low, high GLUT2 levels were detected in all cell lines and tumor models. Besides GLUT1, GLUT5 seems to be regulated under hypoxia on the molecular and functional level. Additionally, results strongly support a functional involvement of GLUT2 in fructose metabolism, possibly by compensating for the weaker expression and function of GLUT5 in BC.-Hamann, I., Krys, D., Glubrecht, D., Bouvet, V., Marshall, A., Vos, L., Mackey, J. R., Wuest, M., Wuest, F. Expression and function of hexose transporters GLUT1, GLUT2, and GLUT5 in breast cancer-effects of hypoxia.

• Authors: Ingrit Hamann, Daniel Krys, Darryl Glubrecht, Vincent Bouvet, Alison Marshall, Larissa Vos, John R Mackey, Melinda Wuest, Frank Wuest
• Journal: FASEB journal : official publication of the Federation of American Societies for Experimental Biology (FASEB J) Vol. 32 Issue 9 Pg. 5104-5118 (09 2018) ISSN: 1530-6860 [Electronic] United States
• PMID: 29913554 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Glucose Transporter Type 1
• Glucose Transporter Type 2
• Glucose Transporter Type 5
• Monosaccharide Transport Proteins
• SLC2A1 protein, human
• SLC2A2 protein, human
• SLC2A5 protein, human
• Fluorodeoxyglucose F18
• Fructose
• Glucose

Topics

• Animals
• Biological Transport (physiology)
• Breast (metabolism, pathology)
• Breast Neoplasms (metabolism, pathology)
• Cell Line, Tumor
• Female
• Fluorodeoxyglucose F18 (metabolism)
• Fructose (metabolism)
• Glucose (metabolism)
• Glucose Transporter Type 1 (metabolism)
• Glucose Transporter Type 2 (metabolism)
• Glucose Transporter Type 5 (metabolism)
• Humans
• Hypoxia (metabolism, pathology)
• Immunohistochemistry (methods)
• MCF-7 Cells
• Mice
• Mice, Nude
• Monosaccharide Transport Proteins (metabolism)
• Positron-Emission Tomography (methods)