TE-1 and KYSE150 cells pretreated with different concentrations of chaetocin for 24 h exhibited a concentration-dependent decrease in the expression of p-CDK1, whereas the expression of p-histone h3 was increased with increasing chaetocin concentration (Figure 2B), indicating that chaetocin causes mitotic arrest in ESCC cells. The gene discussed is CDK1; the disease is esophageal squamous cell carcinoma.