miR-455-3p in peripheral blood is a potentially superior diagnostic marker for prostate cancer to PSA

Purpose Prostate-specific antigen (PSA) is commonly used as a biomarker to diagnose and predict the course of prostate cancer (PCa). However, PSA detection is susceptible to changes in the physiologic environment, which may lead to some misdiagnosis. Thus, it is crucial to find a novel diagnostic marker. Methods GEO2R platform was used to screen for a target miRNA in two GEO datasets (GSE206793 and GSE112264). Correlation between target miRNA and clinical features of PCa was further analyzed and ROC analysis was performed. Next, qRT-PCR was used to assay the target miRNA expression in human peripheral blood samples and validated with GSE206793 dataset. Finally, miRWalk website was used to predict the downstream genes of the target miRNA. STRING website was used to construct a PPI network and perform KEGG pathway analysis. Results Serum miR-455-3p was highly expressed in PC patients and was associated with high Gleason score, independent of tumor stage, age and PSA. miR-455-3p had favorable diagnostic efficacy (AUC > 0.8) and lower misdiagnosis rate compared to PSA. PPP2R2A, ITGB1 and CDKN1A were key targets of miR-455-3p enriched in various cancers, biological processes and molecular signals. Conclusion miR-455-3p can be used as a novel diagnostic marker for PCa, with potentially superior diagnostic efficacy to PSA.