Micro-RNAs With Prognostic Significance in Gallbladder Cancer: A Systematic Review and Meta-Analysis

Gallbladder cancer (GBC) stands out as one of the most widespread malignancies impacting the biliary tract globally. Despite increasing interest, to the best of our knowledge, no meta-analysis has been undertaken to amalgamate the existing data concerning the prognostic significance of micro-RNAs (miRNAs) in GBC in comparison to studies on miRNAs in other cancers. Hence, this systematic review and meta-analysis aimed at determining the prognostic significance of miRNAs in GBC patients. Comprehensive literature searches were conducted across PubMed, Cochrane Library, Ovid, Scopus, and Science Direct databases. Studies that evaluated the association between miRNAs and overall survival in GBC patients were included. Random-effect meta-analysis was employed to pool hazard ratios (HRs) and their 95% confidence intervals (CIs) across studies. A total of 15 studies, encompassing 16 miRs, were included for our analysis. The pooled analysis revealed that a high expression of miR-204, miR-7-2-3p, miR-29c-3p, miR-125b, miR-20a, miR-139-5p, miR-141, miR-92b-3p, miR-335, and miR-372 was significantly associated with poor prognosis and increased risk (HR>1 and the upper bound of the 95% CI>1). Additionally, these miRNAs were associated with the overall survival (HR = 1.56, 95% CI = 0.91-2.20, I = 91.82%). Significant heterogeneity was observed and could be attributed to the limited number of studies available on the GBC and significant reliance on quantitative real-time PCR for the detection of miRNAs. In conclusion, specific miRNAs exhibit prognostic significance in GBC, with potential implications for patient stratification and targeted therapeutic interventions. However, due to the heterogeneity among studies, these findings should be interpreted cautiously and validated in larger cohorts.