That is, without IR treatment, the apoptotic activity of ASK1 was completely repressed by its inhibitors Trx and 14-3-3; thus, without IR treatment, overexpressed DAB2IP per se was incapable of inducing cell apoptosis or suppressing the tumorigenicity of ESCC cells in nude mice (Figs. 3B, C and 4A). This evidence concerns the gene TXN and esophageal squamous cell carcinoma.