Correlation of p53, MDM2 and p14^ARF protein expression in human esophageal squamous cell carcinoma

Purpose: To determine the interrelationships of p53, MDM2, and p14 ^ARF protein expression in primary esophageal squamous cell carcinoma (ESCC) and their prognostic value in ESCC. Methods: In total, 119 patients treated for ESCC with esophagectomy were enrolled in this study. Demographic and clinical data including gender, age, depth of tumor invasion, lymph node involvement, and 5-year survival rate were collected by chart review. p53, MDM2, and p14^ARF were detected immunohistochemically in the resected tumors to evaluate their usefulness as biomarkers of clinical outcome. Results: p53, MDM2, and p14^ARF were expressed in 61 (51.3%), 34 (28.6%), and 22 (18.5%) of 119 tumor specimens, respectively. Overall, p53 protein expression was positively correlated with MDM2 (P = 0.024) and p14^ARF expression (P = 0.026). In addition, p14^ARF expression was most often found in specimens that were positive for both p53 and MDM2. Changes in the p53, MDM2, and p14^ARF protein levels were not correlated with 5-year survival rate. Conclusions: Expression of p53 protein correlates with increased MDM2 and p14^ARF protein levels in ESCC. In addition, status of p53 (wild-type versus mutant) rather than expression level of p53, MDM2, or p14 ^ARF is likely to be the more critical determinant of clinical outcome.