Can expression of CXCL12 and CXCR4 be used to predict survival of gastric cancer patients?

Currently, there is no effective therapy for advanced gastric cancer. In this study, we investigated whether protein expression of CXCL12 and/or its receptor CXCR4 is associated with clinicopathological features and/or survival of gastric cancer. Primary tumor specimens from patients (n=137) with pathologically-confirmed gastric cancer, collected between 2001 and 2009, were analyzed by immunohistochemistry using anti-CXCL12 and anti-CXCR4 antibodies. Expression of CXCL12 was directly associated with tumor differentiation (p=0.0143) but inversely associated with depth of invasion (p=0.0255), lymphatic invasion (p=0.0173), venous invasion (p=0.0022) and stage (p=0.049). Expression of CXCR4 was associated with depth of invasion (p=0.005) and stage (p=0.028). Increased CXCR4 expression, but not CXCL12 expression, was associated with 5-year cancer-specific survival (p=0.0079). CXCL12 was not associated with survival. Positive CXCR4 expression in gastric carcinoma was significantly associated with poor survival and, therefore, may be a potential biomarker for predicting poor survival.