Search

The prognosis of patients with esophageal cancer remains poor, and the tumor-node-metastasis classification system is not sufficient for predicting patient prognoses. Therefore, the identification of novel predictive markers for esophageal cancer is required. The present study investigated the clinicopathological significance of growth arrest and DNA damage-inducible 45α (GADD45A) and p53 in resectable esophageal squamous cell carcinoma (ESCC). The study consisted of 62 patients with esophageal cancer who underwent surgery between 2001 and 2007. The expression of the GADD45A gene product (GADD45A) and the p53 protein was analyzed by immunohistochemistry. The correlations among GADD45A expression, clinicopathological factors and prognosis were then analyzed in the patients with ESCC. GADD45A and p53 were expressed in 56.5% (35/62) and 48.4% (30/62) of patients, respectively. The expression of GADD45A did not show a marked correlation with that of p53. However, GADD45A expression correlated with pathological stage (stage 0-I vs. stages II-IV; P=0.014) and did not correlate with the tumor (T) or node (N) status. Furthermore, patients who were positive for GADD45A exhibited a significantly higher survival rate than those who were negative for GADD45A (log-rank test, P=0.009). Multivariate analysis indicated that T status, N status and GADD45A expression were significant variables predicting survival (hazard ratio, 2.486; 95% confidence interval, 1.168-5.290; P=0.018). Overall, GADD45A expression significantly affected the survival of patients with ESCC, and the reduced expression of GADD45A was correlated with a poor prognosis following curative surgery in these patients.

This study investigated the mRNA levels of thymidylate synthetase (TYMS) and dihydropyrimidine dehydrogenase (DPYD) in esophageal squamous cell carcinoma (ESCC). TYMS and DPYD gene expression was quantified using real-time RT-PCR in 56 patients with ESCC, co-amplified with glyceraldehyde-3-phosphate dehydrogenase as an internal standard. The results were analyzed with reference to the clinicopathological characteristics and the prognosis of the ESCC patients. The TYMS and DPYD expression levels in patients positive with lymphatic invasion were significantly higher compared to those in patients who exhibited negative lymphatic invasion (TYMS P=0.0127, DPYD P=0.0127). Patients were classified into the groups high TYMS/DPYD, high TYMS but low DPYD, low TYMS but high DPYD and low TYMS/DPYD. The highest survival rate was found in the group with low TYMS/DPYD and the lowest survival rate in the group with high TYMS/DPYD (P=0.017). It was concluded that, on the basis of the multivariate analysis, TYMS mRNA expression is a candidate that serves as an independent prognostic factor for ESCC patients.