Figure 1.

Intratumoral hypoxia correlates with reduced mTOR activation in human HNSCC. Moderate to intense immunodetection of the hypoxia marker Glut-1 (A: subpanels a–c) was frequently found in areas where the activation status of the mTOR downstream target S6 (pS6) was reduced or absent (A: subpanels d–f). Immunohistochemistry was performed on tissue sections from representative human HNSCC specimens using antibodies against Glut-1 and pS6 to determine the effects of regional intratumoral hypoxia on the mTOR pathway in vivo. (B) In hypoxic foci, the relative distribution of Glut-1 immunostaining was significantly increased when compared to tumor cells positively stained with pS6 (*P < .05). Data represent the mean ± SEM.