Prognostic Significance of COX-2 Immunohistochemical Expression in Colorectal Cancer: A Meta-Analysis of the Literature

Abstract

BackgroundCyclooxygenase-2 (COX-2) is believed to be an important enzyme in the pathogenesis of colorectal cancer (CRC). Correlations between the expression of COX-2 with tumor growth and distant metastasis have become an issue; thus, attention has been paid to COX-2 as a prognostic factor. Various studies examined the relationship between COX-2 immunohistochemistry (IHC) overexpression with the clinical outcome in patients with colorectal cancer, but yielded conflicting results. The prognostic significance of COX-2 overexpression in colorectal cancer remains controversial.MethodsElectronic databases updated to October 2012 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between COX-2 overexpression and survival of patients with colorectal cancer. Survival data were aggregated and quantitatively analyzed.ResultsWe performed a meta-analysis of 23 studies (n = 4567 patients) that evaluated the correlation between COX-2 overexpression detected by IHC and survival in patients with colorectal cancer. Combined hazard ratios suggested that COX-2 overexpression had an unfavorable impact on overall survival (OS) (HR [hazard ratio] = 1.193, 95% CI [confidence interval]: 1.02 ∼ 1.37), but not disease free survival (DFS) (HR = 1.25, 95% CI: 0.99 ∼ 1.50) in patients with colorectal cancer.ConclusionsCox-2 overexpression in colorectal cancer detected by IHC appears to have slightly worse overall survival. However, the prognostic value of COX-2 on survival in colorectal cancer still needs further large-scale prospective trials to be clarified.

Prostanoid induces premetastatic niche in regional lymph nodes

“…jci.org Volume 124 Number 11 November 2014 production (8). COX-2 expression is associated with poor patient prognosis and survival (33,34). We previously reported that, in addition to tumor COX-2 expression, COX-2 present in stromal tissues had a significant effect on tumor-associated angiogenesis (35).…”

Impact of cyclooxygenase-2 and prostaglandin-E2 expression on clinical outcome after pulmonary metastasectomy

“…In addition to that the majority of included publications found only an indeterminate association of COX and patient prognosis. Of note most studies comprised a mixture of primary CRC patients and no analysis on the prognostic role of COX-2 in pulmonary metastases (27). One has to be careful when transferring conclusions from primary tumors to metastasized tumor stages.…”

COX-2 expression correlation with invasion in human breast carcinomas and in cell line MDA-MB-231 in vitro

“…Other factors which may be associated with COX-2 in breast cancer, which should be investigated in further studies. It is critical for breast cancer management to identify those biomarkers that would provide those factors potentially curable given the availability of early diagnosis and effective therapeutic protocols, at the time of diagnosis, a reliable prognostic assessment and prediction of treatment response (Thorat et al, 2013;Peng et al, 2013 ).…”