Aberrant expression of β-catenin in membrane and cytoplasm/nucleus are associated with poor prognosis of gastric cancer: evidence from an updated meta-analysis

The effect of beta-catenin expression on the prognosis of gastric cancer (GC) has been investigated by a previous meta-analysis, however, it missed a few studies apparently meeting the inclusion criteria. Recent studies with large sample size further researched this issue, but controversies still remain. To explore the issue clear and draw a firm conclusion to guide clinical practice, the present study updated the meta-analysis by adding these studies. A comprehensive database searching was conducted in the PubMed, EMBASE, and Web of Science in August 2015. After screening, 23 studies with 4212 GC patients were finally included in the meta-analysis. The methodological quality of included studies was assessed by the Newcastle-Ottawa quality assessment scale and the survival data was pooled by STATA 11.0. The results of meta-analysis showed that aberrant expression of beta-catenin was associated with a significant increase of mortality risk of GC patients (hazard ratio, 1.63; 95% confidence interval, 1.40-1.90). The subgroup analysis showed that aberrant expression of beta-catenin resulted in poor overall survival of GC patients regardless of location of patients, sample size of study, or method of HR estimation. The present study demonstrated that both types of aberrant expression of beta-catenin, including overexpression in cytoplasm and/or nucleus and reduced expression in membrane, could be predicative factors of poor prognosis in GC patients.