PRDX6 and esophageal squamous cell carcinoma: In our previous studies, we found that serum levels of autoantibodies against BMI-1, HSP70, MMP-7, NY-ESO-1, p53 and PRDX6 were all significantly elevated in sera of esophageal squamous cell carcinoma patients and gastroesophageal junction adenocarcinoma patients, compared to controls 16, 17.