To clarify the biological significance of THAP9-AS1 in ESCC progression, siRNAs specifically targeting THAP9-AS1 including si-THAP9-AS1#1 and si-THAP9-AS1#2 were transfected into Eca-109 and KYSE-30 cells. The gene discussed is THAP9; the disease is esophageal squamous cell carcinoma.