In this study, we investigated the relationship between TGF-β1/Smad signaling and EMT in ESCC using recombinant TGF-β1 and SB431542, a potent inhibitor of ALK5 that inhibits TGF-β type II receptor, in human ESCC cell lines. The gene discussed is TGFBR1; the disease is esophageal squamous cell carcinoma.