Identification of genomic biomarkers associated with the clinicopathological parameters and prognosis of esophageal squamous cell carcinoma

BACKGROUND: At present no objective prognostic biomarkers have been established in esophageal squamous cell carcinoma (ESCC). OBJECTIVE: To identify the genomic biomarkers associated with clinicopathological factors and prognosis of ESCCs. METHODS: Real-time PCR was used to analyze the copy number change and mRNA expression of genes. The survival curves were plotted according to Kaplan-Meier method and checked by log-rank test. RESULTS: We revealed the copy number increase of CACNA1C (12p13.33) and MRPL21 (11q13.2) as well as decrease of VIPR2 (7q36.3) and MAP3K7 (6q15) in ESCC by Real-time PCR, and also found that MRPL21 was significantly overexpressed and VIPR2 was underexpressed in ESCC. Gain of CACNA1C was significantly associated with differentiation (P = 0.043), and loss of VIPR2 was significantly linked with good prognosis (P = 0.016). Most importantly, we revealed that loss of MAP3K7 was significantly correlated with good prognosis in ESCC patients (n = 159, P = 0.004), especially in Grade II and pN0 patients (n = 76, P = 0.005 and n = 74, P = 0.024). Multivariate analysis confirmed that MAP3K7 loss provided prognostic information in ESCC (HR, 0.454; 95% CI: 0.208-0.995; P = 0.048). CONCLUSIONS: Loss of MAP3K7 may be a candidate prognostic factor in ESCC.