Indeed, several groups have now described inhibitors of Glut1 with partial activity that can suppress tumor growth.38, 39, 40, 41 The HIV protease inhibitor, ritonavir, also shows non-selective partial inhibition of both Glut1 and Glut4 with low toxicity.42 Although it remains unclear to what extent Glut1 may provide a direct pharmacologic target, our data indicate that it is not essential to fully suppress glucose uptake to prevent cancer cell proliferation and disease progression. Here, SLC2A4 is linked to cancer.