Clinicopathological and prognostic significance of MUC4 expression in cancers: evidence from meta-analysis

Mucin4 (MUC4) is a secreted glycoprotein. Numerous studies had indicated that MUC4 was an attractive prognostic tumor biomarker. However, the results of different studies have been inconsistent. So we conducted this meta-analysis to explore the association between MUC4 expression and cancer prognosis. A systematically comprehensive search was performed through PubMed, EMBASE and CNKI (Chinese National Knowledge Infrastructure). Prognostic value of MUC4 expression in malignancy patients was evaluated by pooled hazard ratios (HRs) and their 95% confidence intervals (CIs). Meanwhile, pooled odds ratio (OR) with 95% CI was appropriate for the association between MUC4 expression and clinicopathological parameters. Eighteen studies including 1,933 patients were enrolled in this meta-analysis. Significant association was found between elevated MUC4 expression and poorer overall survival (OS) with pooled hazard ratio (HR) of 1.87 [95% confidence interval (CI): 1.58-2.23, P<0.001]. Significant associations were also detected in biliary tract carcinoma (HR: 2.41, 95% CI: 1.69-3.42, P<0.001), pancreatic cancer (HR: 2.01, 95% CI: 1.42-2.86, P<0.001) and colorectal cancer (HR: 1.73, 95% CI: 1.17-2.54, P=0.006). Moreover, combined odds ratio (OR) of MUC4 indicated that MUC4 overexpression was associated with tumor stage, tumor invasion and lymph node metastasis. Our results demonstrated that MUC4 may be exploited as a novel prognostic biomarker for cancer patients.