Link between miR-19b and the mTOR signaling pathway in cancer prognosis

Objective Previous studies have reported differing conclusions regarding the prognostic value of miR-19b in cancers.Moreover,miR-19b may affect tumor growth by different pathways,mainly targeting PTENPI3K-AKT,which activates the downstream mTOR pathway.Therefore,we performed data mining to explore the possible correlation between miR-19b and mTOR in cancer prognosis.Methods We conducted online search and collected a total of 943 articles.According to different authors cross check and our study including/excluding criteria we at end retained 21 articles with 25 studies in this meta-analysis.Then TCGA data containing miR-19b level with cancer progression were obtained using OncomiR.Furthermore,Trial Sequential Analysis(TSA)was performed to determine whether the results of our meta-analysis could be used in clinical applications.After that,articles regarding the mechanism of miR-19b in various cancers were analyzed and KEGG pathway database was used to find the main regulatory function of miR-19b in human cancers.Results Overall hazard ratio(HR)results showed that higher levels of miR-19b expression were correlated with shorter overall survival time[HR=1.54,95%confidence interval(CI)=1.20-1.98]by promoting distant metastasis,but had no correlation with disease-free survival(DFS)/progression-free survival(PFS;HR=0.61,95%CI=0.31–1.19).Data from The Cancer Genome Atlas also revealed the role of miR-19b in tumorigenesis.According to trial sequential analysis results,more evidence is required to confirm that miR-19b is not correlated with DFS/PFS.Exploration of the mechanism revealed a possible link between miR-19b and the mTOR pathway.Conclusion miR-19b may have a pro-carcinogenic role through the mTOR pathway and thus,it is likely to be a therapeutic target for cancers.