LncRNA MEG3 inhibits the progression of prostate cancer by modulating miR-9-5p/QKI-5 axis

This study was designed to detecting the influences of lncRNA MEG3 in prostate cancer. Aberrant lncRNAs expression profiles of prostate cancer were screened by microarray analysis. The qRT-PCR and Western blot were employed to investigating the expression levels of lncRNA MEG3, miR-9-5p and QKI-5. The luciferase reporter assay was utilized to testifying the interactions relationship among these molecules. Applying CCK-8 assay, wound healing assay, transwell assay and flow cytometry in turn, the cell proliferation, migration and invasion abilities as well as apoptosis were measured respectively. LncRNA MEG3 was a down-regulated lncRNA in prostate cancer tissues and cells and could inhibit the expression of miR-9-5p, whereas miR-9-5p down-regulated QKI-5 expression. Overexpressed MEG3 and QKI-5 could decrease the abilities of proliferation, migration and invasion in prostate cancer cells effectively and increased the apoptosis rate. On the contrary, miR-9-5p mimics presented an opposite tendency in prostate cancer cells. Furthermore, MEG3 inhibited tumour growth and up-regulated expression of QKI-5 in vivo. LncRNA MEG3 was a down-regulated lncRNA in prostate cancer and impacted the abilities of cell proliferation, migration and invasion, and cell apoptosis rate, this regulation relied on regulating miR-9-5p and its targeting gene QKI-5.