Depicted in Figure 1C, the tumor burden in mice lacking Hif-1α (mean tumor burden: 0.303% ± 0.303) and Hif-1α/2α (0.438% ± 0.347) was smaller than in wt mice (1.496% ± 0.379), whereas the mean tumor burden in Hif-2αLysM−/− mice (3.185% ± 0.833) was not significantly enhanced compared to wt mice. This evidence concerns the gene HIF1A and neoplasm.