Expression and prognostic value of MG7-Ag in patients with surgically resectable esophageal squamous cell carcinoma

MG7-Ag is a human gastric-carcinoma-associated antigen. The expression of MG7-Ag was found to increase gradually with the development and progression of gastric cancer. Moreover, a poorer prognosis was found in MG7-Ag positive gastric-carcinoma patients than in MG7-Ag negative patients. However, neither MG7-Ag expression nor its clinical significance has been previously examined in squamous cell carcinoma (SCC) of the esophagus. In this study, we examined the expression of MG7-Ag in esophageal squamous cell carcinomas to assess its value as a prognostic indicator.

The expression of MG7-Ag was detected in 112 cases of esophageal squamous cell carcinoma (SCC) by immunohistochemical analysis. The relation of MG7-Ag staining with various clinicopathological features was statistically analyzed.

The staining of MG7-Ag was detected in SCC, while not in normal epithelial cells. In esophageal SCC, MG7-Ag was found significantly correlated with depth of invasion (P = .012), in T4, T3 carcinomas but not in T2, T1 carcinomas, lymph node metastases (P = .029), pathological stage (P = .005). Consistently, the survival rate tended to be statistically lower in patients with MG7-Ag positive SCCs than in MG7-Ag negative SCCs (P = .005). However, no significant difference was observed between MG7-expression and patient age, sex, tumor location, differentiation, distant metastasis, and lymphatic invasion.

MG7-Ag might play a positive role in the process of carcinogenesis and progression of esophageal SCC, and it could be considered as one valuable prognostic indicator in esophageal SCC.