We focused on the cell membrane protein and confirmed relatively low GPC-1 expression in normal tissues relative to ESCC.19 GPC-1 expression in ESCC is related to poor prognosis and chemoresistance, as previously reported.19 In this study, IHC analyses showed that 97.3% of PDAC specimens were GPC-1 positive, and GPC-1 overexpression was related to poor prognosis. The gene discussed is GPC1; the disease is esophageal squamous cell carcinoma.