Association of Kruppel-like factor 4 expression with the prognosis of esophageal squamous cell carcinoma patients.

To investigate the association of Kruppel-like factor 4 (KLF4) expressions with the prognosis of esophageal squamous cell carcinoma (SCC) patients. Ninety-eight cases of esophageal carcinoma patients were enrolled. The expression of KLF4 in the esophageal SCC and normal esophageal mucosa tissues were examined by immunohistochemistry. The correlations between the expression of KLF4 protein and patients' clinical characteristics and prognosis were analyzed. We observed higher expressed KLF4 in normal esophageal mucosa tissues than esophageal SCC tissues, with positive rate of 82.7% (81/98) and 43.8% (43/98) respectively. In patients with lymphatic metastasis, the positive rate of KLF4 was 24.4% (10/41), whereas it was 57.9% (33/57) in patients without lymphatic metastasis, and the difference was significant (x(2) = 10.871, P = 0.001). The positive rates of KLF4 were 62.5% (5/8), 53.1% (26/49) and 29.3% (12/41) in stage I, II and III patients, respectively. There were no correlations between the expression of KLF4 and gender, age, tumor size, location, differentiation grade and infiltration depth. The 5-year survival rates and median survival times were 48.8% and 25.5%, and 55 and 26 months for the patients with KLF4 positive and negative expression, respectively. There were significant differences between the patients with KLF4 positive expression and negative expression in the 5-year survival rates and median survival times (x(2) = 5.747 and 4.493, P = 0.017 and 0.034). KLF4 might act as a tumor suppressor in esophageal SCC and the expression status of KLF4 could be considered as a prognosis predictor for esophageal SCC patients.