Clinical assessment of miRNA-23b as a prognostic factor for various carcinomas: A systematic review and meta-analysis

Objectives: miRNA-23b has been proposed to have a significant role in the prognosis of several types of tumors, despite the potential impact of its expression is still controversial. Innovative prognostic biomarkers for the prediction of cancer outcomes and the usage as therapeutic targets are warranted. We conducted this systematic review and meta-analysis to evaluate the associations between miRNA-23b expression and overall survival (OS) in various carcinomas. Methods: We searched PubMed, Scopus, Web of Science, and Cochrane Central Register for relevant articles through May 2019. Data on the association of miRNA-23b expression and the OS was extracted and pooled in a meta-analysis model as a hazard ratio (HR) with the respective 95% confidence interval (CI). We used RevMan software version 5.2. Results: Twelve eligible studies (n = 1589 patients) were included in our meta-analysis. The miRNA-23b downregulation was significantly associated with a more reduced OS (HR = 3.2, 95% CI [2.26 to 4.53], P < .00001). In plasma exosomes of gastric and breast cancer patients, the pooled effect size showed that miRNA-23b upregulation was linked with poor OS (HR = 1.59, 95% CI [1.07 to 2.37], P < .02). The poor OS for patients with low miRNA-23b remained statistically significant regardless of the method of quantitative reverse transcription-polymerase chain reaction or the type of sample used (all P < .00001). Conclusions: Low expression of miRNA-23b is significantly associated with poor OS in most of the cancer types and high-expressed in breast and plasma exosomes of gastric cancers. miRNA-23b could be an independent prognostic biomarker and therapeutic target. Further studies are needed to confirm these findings.