Expression and prognostic roles of Eag1 in resected esophageal squamous cell carcinomas

Expression of Eag1 was detected in resected esophageal squamous cell carcinomas tissues and matched tissues by immunohistochemistry and RT-PCR. Positive expression of Eag1 protein was 75% (51/68), and mRNA was 73% (8/11) in primary cancer tissues. Eag1 protein positively stained in all 10 metastatic lymph nodes. Eag1 protein and mRNA were negatively expressed in all non-cancerous matched tissues. Eag1 protein was associated with depth of penetration (P = 0.023), but not associated with other clinicopathological factors. Eag1 protein positive group had a significantly shorter survival time than the negative group (P = 0.005). Survival rates at each time-point for the positive group were lower than that for the negative group (P = 0.006), and Eag1 was identified as an independent prognostic factor of long-term survival (P = 0.016). In conclusion, Eag1 was aberrantly expressed in ESCC and correlated with poor prognosis after surgery.