Decreased expression of CIAPIN1 is correlated with poor prognosis in patients with esophageal squamous cell carcinoma.

BACKGROUND: CIAPIN1, a newly identified antiapoptotic molecule, is a downstream effector of the receptor tyrosine kinase-Ras signaling pathway in the mouse Ba/F3 pro-B cell line. Neither CIAPIN1 expression nor its clinical significance has been previously examined in esophageal squamous cell carcinoma (ESCC), and the present immunohistochemical analysis is the first study on CIAPIN1 distribution in ESCC. AIMS: To investigate the relationships between the expression of CIAPIN1 and clinicopathological characteristics of ESCC, and evaluate the relationship between the expression of this gene and prognosis in ESCC patients.
METHODS: The expression of CIAPIN1 was investigated in 112 surgically resected specimens of ESCC by immunohistochemistry using a specific monoclonal antibody. The relations of CIAPIN1 expression with clinicopathological characteristics and the postoperative survival rate were statistically analyzed.
RESULTS: We found that the expression of CIAPIN1 was statistically correlated with the degree of differentiation, depth of invasion, and lymph node metastasis of ESCC. Consistently, the survival rates of patients with CIAPIN1-negative tumors tended to be statistically lower than those with CIAPIN1-positive tumors. However, no significant difference was observed between CIAPIN1 expression and the patient age, sex, tumor location, and distant metastasis. Furthermore, multivariate analysis was performed by using Cox's proportional hazards model, and the results showed that lymph node metastases and CIAPIN1 expression were two independent prognostic factors.
CONCLUSIONS: CIAPIN1 might play an important role in esophageal carcinogenesis, and it could be considered as a valuable prognostic indicator in ESCC. Finally, functional enhancement of CIAPIN1 might lead to a novel strategy for the treatment of SCC in the esophagus.