Taken together with the results from western blotting and IIF analysis, our data indicate that Prdx1 induces strong humoral autoimmune responses in some ESCC patients, suggesting that Prdx1 may be an ESCC-associated autoantigen, and the autoantibody against Prdx1 can be used as a potential serological biomarker in the immunodiagnosis of ESCC. Here, PRDX1 is linked to esophageal squamous cell carcinoma.