Abstract
Background/Purpose
We showed that eicosapentaenoic acid (EPA) stimulated apoptosis via caspases in ESCC cell lines, indicating an anti-cancer effect. In the present study, we aimed to clarify whether the anticancer and anti-inflammatory actions of EPA are related to COX-2.
Materials and method
We performed immunohistochemical analysis in 92 ESCC specimens to investigate the relationship between COX-2 expression and prognosis, and Western blotting in ESCC cell lines to determine whether EPA suppresses COX-2.
Results
Immunohistochemistry showed that COX-2 expression levels were enhanced in the ESCC specimens, with a significant prognostic impact on the survival of surgically treated cases (P=0.0017, log-rank test). Multivariate analysis showed that the prognostic impact of COX-2 is independent of disease stage (P=0.02). Western blotting revealed that the KYSE180 and TE11 ESCC cell lines express COX-2, which was greatly suppressed by EPA stimulation.
Conclusions
The expression of COX-2 in patients with ESCC is associated with significantly poor survival rates. EPA may have an anti-cancer effect via suppression of COX-2.