Abstract: Objective To investigate the expression of enhancer of zeste homolog 2 (EZH2) in esophageal squamous cell
carcinoma and its association with the prognosis of postoperative patients. Methods Surgical specimens were obtained from
102 patients with esophageal squamous cell carcinoma undergoing radical resection in our hospital from 1996 to 2006.
Immunochemistry was employed to examine EZH2 protein expressions in the specimens, including 102 carcinoma tissue
specimens, 30 adjacent tissue specimens and 30 normal esophageal tissue specimens. The expression levels of EZH2 were
analyzed in relation to the clinicopathological parameters of the patients including gender, age, tumor differentiation, TNM,
and lymph node metastasis. The postoperative patients were followed up to analyze the association of EZH2 expression with
the clinical outcomes. Results The esophageal squamous cell carcinoma tissue showed a higher EZH2 expression than the
adjacent and normal esophageal tissues. EZH2 expression was higher in poorly differentiated carcinoma than in well
differentiated tissue, and also higher in cases with lymph node metastasis than those without; the expression was higher in
TNM stage Ⅱ/Ⅲ patients than in stage I patients but lower than in stage IV patients. The patients with low EZH2 expression
was found to have a longer survival time than those with high EZH2 expression (P<0.05). Conclusion EZH2 plays an
important role in the differentiation and metastasis of esophageal squamous cell carcinoma, and a high EZH2 expression is
associated with a poor outcome in the the postoperative patients.