The prognostic value of AGR2 expression in solid tumours: a systematic review and meta-analysis

The prognostic value of anterior gradient-2 (AGR2) in tumours remains inconclusive. Here, we systematically reviewed the literature evidence and assessed the association between AGR2 expression and prognosis in solid tumours. The primary outcomes were overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS)/recurrence-free survival (RFS)/progression-free survival (PFS). All analyses were performed by STATA 12.0, with the hazard ratio (HR) or odds ratios (OR), and 95% confidence interval (CI) as the effect size estimate. A total of 20 studies containing 3285 cases were included. Pooled analyses revealed that AGR2 overexpression had an unfavourable impact on OS (HR 1.93, 95% CI 1.32-2.81) and time to tumour progression (TTP) (DFS/RFS/PFS) (HR 1.60 95% CI 1.06-2.40) in solid tumour patients. Subgroup analyses indicated that AGR2 overexpression in breast cancer patients was significantly associated with poor OS (HR 3.02, 95% CI 1.03-8.81) and TTP (HR 1.93, 95% CI 1.17-3.20). Excluding breast cancer, AGR2 overexpression was also found to have a significant correlation with poor OS in the remaining solid tumour patients (HR 1.51, 95% CI 1.04-2.19). Overall, AGR2 might be a potential biomarker to predict prognosis in solid tumour patients.