High miR-34a and miR-26b expressions inhibit prostate cancer cell OPCN-1 proliferation and enhances apoptosis

Purpose: To investigate the effects of miR-34a and miR-26b on the targeted genes, LEF1 and EphA2, and proliferation and apoptosis of OPCN-1.Methods: Sixty specimens of cancer tissue (CT) and equivalent tissue adjacent to tumors (TAT) were collected from prostate cancer patients. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to determine the mRNA expression levels of miR-34a, miR-26b, LEF1, and EphA2 in the above tissues, while protein expression levels of LEF1 and EphA2 were evaluated by Western blot.Results: Compared with TAT, the expression levels of miR-26b and miR-34a in CT decreased significantly (p < 0.05), whereas the mRNA and protein expression levels of EphA2 and LEF1 in CT significantly increased (p < 0.05). TargetScanHuman7.2 assay data revealed that miR-26b targeted EphA2, while miR-34a targeted LEF1. MiR-26b MG showed decreased EphA2 mRNA and protein levels when compared with miR-26b-NC group after overexpression. The miR-34a MG exhibited decreased expression levels of LEF1 mRNA and protein compared with the miR-34a-NC group. Between 48 and 72 h, miR-26b MG grew more slowly than miR-26b-NC group; miR-34a MG also showed significantly slower growth than miR-34a-NC group. The miR-26b MG and miR-34a MG groups displayed higher apoptosis rate than miR-26b-NC and miR-34a-NC groups, respectively.Conclusion: High expressions of miR-34a and miR-26b targeted the inhibition of LEF1 and EphA2, respectively, indicating that they inhibit the proliferation, and also control the increased apoptosis rate of OPCN-1 cells. Hence, miR-34a and miR-26b are probable molecular targets for the development of new prostate cancer drugs.