Objective  To determine the expression and clinical significance of the FoxO1 and Ki-67 proteins in esophageal squamous cell carcinoma(ESCC) and normal esophageal epithelial tissue.

  Methods  Streptavidin-peroxidase(SP) staining was used to detect the expression of FoxO1 and Ki-67 in 36 ESCC samples and 12 samples of normal esophageal epithelium.

  Results  The positive expression rate of FoxOl was 75.00%in ESCC and 16.67%in the normal esophageal epithelium tissue.The positive expression rate of Ki-67 was 83.33%in ESCC and 0%in the normal esophageal epithelium tissue.The positive expression rates of FoxO1 and Ki-67 were significantly higher in ESCC than in normal esophageal tissue(P < 0.01).Among the ESCC cases, the rates of positive FoxO1 and Ki-67 expression were related to the degree of ESCC differentiation.The rate of positive FoxO1 expression increased as the degree of pathological differentiation increased(P < 0.01);however, the rate of positive Ki-67 expression decreased as the degree of pathologic ESCC differentiation increased(P < 0.01).No significant correlation was observed among other clinicopathologic features.

  Conclusion  The positive expression rates of FoxOl and Ki-67 are significantly higher in ESCC than in normal esophageal epithelial tissue.As the degree of pathologic ESCC differentiation increases, the rate of positive FoxOl expression increases, whereas that of Ki-67 decreases. FoxO1 and Ki-67 play different roles in ESCC differentiation, and the mechanism of action is different.