Eca109 and KYSE450 esophageal cancer cell lines were cultured under normoxia, hypoxia, or CoCl2-induced hypoxia conditions, which were further transfected with plasmids expressing RB binding protein 7 (RBBP7), hypoxia-inducible factor 1 (HIF1)-α, or RBBP7 shRNA. The gene discussed is HIF1A; the disease is esophageal cancer.