Expression of Polyadenylate-binding Protein Cytoplasmic 1 (PABPC1) in Combination With RAD51 as Prognostic Biomarker in Patients Who Underwent Postoperative Chemotherapy for Esophageal Squamous Cell Carcinoma.

Molecular markers in the prognosis of esophageal squamous cell carcinoma (ESCC) patients who received postoperative treatments are lacking. This research aims to evaluate the prognostic value of polyadenylate-binding protein cytoplasmic 1 (PABPC1) alone and in combination with RAD51 in ESCC patients who underwent postoperative chemotherapy (CT). A total of 103 ESCC patients who underwent postoperative CT and 103 matched ones who received surgery alone were analyzed in this study. PABPC1 and RAD51 expression was assessed in cancer samples by immunohistochemistry. PABPC1 high expression (PABPC1-HE) but not that of RAD51 was associated with poor patients' survival, regardless of the postoperative treatment or node status. Patients with PABPC1 low expression and RAD51 negative expression [RAD51- (PABPC1-LE/RAD51-)] tumor had good overall survival (OS) in both the CT treated and untreated groups. Patients with PABPC1-LE/RAD51+ and PABPC1-HE/RAD51+ tumors had longer OS in the CT treated group than in the untreated group. However, PABPC1-HE/RAD51- was associated with a poor outcome in both groups and the patients with PABPC1-HE/RAD51- tumor had hardly any benefit from CT in N+ status. PABPC1 alone and in combination with RAD51 was a prognostic biomarker for OS in ESCC patients who received postoperative CT.