We also examined the relationship between the PSMD2, ASS1, LC3 and p62 expression levels determined by IHC staining in mice xenografts derived from ESCC cells with the PSMD2 expression changes, and the results were consistent with the in vitro findings that PSMD2 increases the expression of ASS1 and inhibits autophagy (Fig. 2H, I, Additional file 1: Fig. S4A–D). Here, ASS1 is linked to esophageal squamous cell carcinoma.