Potential Targets and Clinical Value of MiR-224-5p in Cancers of the Digestive Tract.

Background/Aims: MicroRNAs participate in various biological processes in malignant tumors. However, the mechanisms of miR-224-5p in digestive system cancers are not fully understood. A comprehensive investigation of the clinical value and potential targets of miR- 224-5p in cancers of the digestive tract is necessary. Methods: Expression profiling data and related-prognostic data of miR-224-5p were acquired from Gene Expression Omnibus, The Cancer Genome Atlas, ArrayExpress, and published literature. The potential target mRNAs of miR-224-5p were predicted using bioinformatics methods and finally annotated using Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Results: MiR-224-5p is up-regulated in digestive system cancers (SMD=0.69, 95% CI: 0.43-0.96, P<0.0001) and exhibits a moderate diagnostic ability (AUC=0.84, 95% CI: 0.80-0.87). Our data also demonstrated that miR-224-5p is statistically significantly correlated with overall survival univariate analysis (HR=1.69, 95% CI: 1.15-2.49, P=0.007) and multivariate analysis (HR=2.39, 95% CI: 1.74-3.30, P<0.0001). In total, 388 potential miR-224- 5p target mRNAs were predicted by bioinformatics methods. GO annotation analysis revealed that the top terms of miR-224-5p in biological process, cellular component and molecular function were system development, neuron part, and transcriptional activator activity, RNA polymerase II core promoter proximal region sequence-specific binding, respectively. Moreover, eight pathways were identified in KEGG pathway enrichment analysis. Conclusions: MiR-224- 5p is up-regulated and has the potential to become a diagnostic and prognostic biomarker in digestive system cancers. MiR-224-5p might play vital roles in cancers of the digestive tract but the exact molecular mechanisms need further study and verification. [ABSTRACT FROM AUTHOR]