It could significantly inhibit cobalt chloride (CoCl2)- or hypoxia-induced HIF-1α accumulation in human cancer cells (HCT116 and HT29 cell lines), as well as suppress CoCl2-induced activity of hypoxia response element reporter gene and HIF-1α-dependent transcription of gene such as glucose transporter 1, lactate dehydrogenase A, carbonic anhydrase-IX, and pyruvate dehydrogenase kinase 1. The gene discussed is HIF1A; the disease is cancer.