Fig. 5

Overcoming hypoxia-Induced radioresistance through HIF-1α suppression by mannose and PMI Knockout. A) Schematic mannose treatment schedule of colony forming assay. Colony forming assays in WT and PMI KO/KD B i & ii) FaDu, and C i & ii) CAL27 cells +/- mannose (20 mM) for 24 h prior to radiation treatment (RT). Four hours before RT, cells were transferred to an InvivO₂ hypoxic workstation set to 0.5% O₂. D) Western blot and E) semi-quantitative analysis of relative HIF-1α levels in WT and PMI KO/KD cells. D i & E i) FaDu and D ii & E ii) CAL27 cells +/- mannose for 24 h, with a 4 h hypoxia incubation prior to sample collection. F) Relative levels of succinate in WT and PMI KO/KD i) FaDu and ii) CAL27 cells pretreated +/- mannose (20 mM) for 24 h, with a 4 h hypoxia incubation prior to sample collection. G) Relative ATP levels of WT and PMI KO/KD i) FaDu and ii) CAL27 cells pretreated +/- mannose (20 mM) for 24 h, with a 4 h hypoxia incubation prior to sample collection. Data presented (panels B, C, E-G) are mean ± SD of three independent biological replicates. *p ≤ 0.05 -One-way ANOVA - Tukey’s multiple comparisons test E-G) and two-way ANOVA - Tukey’s multiple comparisons test B&C)