ACTB and esophageal squamous cell carcinoma: Band densitometry analysis confirmed these changes to be significantly altered upon TGF-β1 treatment (Fig. 2B, P<0.05, Y axis: optical densities of test bands versus β-actin bands), further suggesting that TGF-β1 signaling pathway is involved in the EMT process in ESCC cells (Fig. 2 E, F, I, and J).