To test the hypothesis that the activation of HIF signaling could compromise the anti-cancer effect of BIX-01294 in chronic hypoxia, we used acriflavine (ACF), which is known to inhibit HIF1α and 2α [46] and has shown therapeutic potential for use against chronic myeloid leukemia [47]. The gene discussed is HIF1A; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.