A recent paper in Nature Neuroscience by Flavahan et al. shows that brain tumor initiating cells (BTICs), have special adaptations that not only allow them to survive hypoglycemic conditions, but also to proliferate. The authors in a series of experiments, show that when exposed to hypoglycemic conditions, cells taken from brain tumor samples acquire stem-like features such as expressing higher levels of the stem cell markers Sox2 and Oct4 and also of CD133+. BTICs survive, otherwise lethal hyperglycemic conditions due to high expression of the glucose transporter, Glut3 , which is highly sensitive to glucose. The BTICs adapt to the hypoglycemic conditions, due to the high glucose sensitivity of Glut3, which allows the cells to detect and take up even very low levels of glucose. At the next level, meta-analysis of multiple brain tumor data sets, showed that high Glut3 expression in brain tumors is associated with patients with poor survival. Interestingly, Glut3 is also associated with poor survival in other types of cancers such as breast, ovary and colon. In addition , this study shows that Glut3 expression is associated with pluripotency. This, suggests that it might be a common mechanism which tumors use evolve and expand. Thus, the a in depth study of the role of Glut3 in tumorigenesis could prove valuable in fighting cancer.
Flavahan, W. et al. Nat. Neurosci. 16, 1371–1380 (2013).