In contrast, the knockdown of PGK1 slowed down the cell proliferation, which was further inhibited by double-knock down of PGK1 and ERK2 in those four kinds of ESCC cell lines (t-test, p < 1.0E–3) (Supplementary Fig. 8f, g and Supplementary Data 7h). The gene discussed is PGK1; the disease is esophageal squamous cell carcinoma.