Cell proliferation of H1299, A549 (NSCLC), MCF7, MDAMB231 (Breast cancer), MKN1, MKN45 (Gastric cancer), and U87MG, SHSY5Y (Brain cancer) cells was dependent on HIF-1α, and HCC cell proliferation was dependent on HIF-2α under hypoxia (Figure 1A,C). The gene discussed is HIF1A; the disease is breast cancer.