A Study Of Hsa-miR-146a Inducing Apoptosis Of Castration-Resistant Prostate Cancer By Inhibiting NF-κB Pathway

Objective:This study suggested that hsa-miR-146a may be related to the occurrence and development of prostate cancer, the experiment in vitro showed the effect of the biological behavior in hsa-miR-146a on castration-resistant prostate cancer cell line DU145 and PC3. To identify the downstream target gene which regulated by hsa-miR-146a, this study revealed the molecular mechanism of hsa-miR-146a in the occurrence and development of prostate cancer, and further investigated the sensitivity of hsa-miR-146a enhancement of castration-resistant prostate cancer cells to TRAIL and promote apoptosis.Methods:The differences of expression of hsa-miR-146a in androgen-dependent prostate cancer (ADPC) specimens and CRPC specimens were measured by microarray analysis and validated by qRT-PCR. Effects of miR-146a in cell apoptosis in vitro were evaluated by Flowcytometry after hsa-miR-146a/NC was transfected into prostate cancer cell;Target gene of Hsa-miR-146a was predicted by systemic bioinformatic analysis such as TargetScan and so on. Luciferase assay and Western Blotting were performed to validate the target gene. In vitro, TRAIL and hsa-miR-146a were used to intervene prostate cancer cell line DU145. MTT assay was used to measure ell viability. Hoechst staining was used to observe the impact of high expression of miRNA-146a and TRAIL on the apoptosis of prostate cancer cells.Results:The expression level of hsa-miR-146a in castration-resistant prostate cancer tissue was significantly decreased compared to hormone-dependent prostate cancer tissues by MicroRNAs chip, and the real-time quantitative PCR verified the microarray results (P<0.05); Cell apoptosis was significantly higher in miR-146a group compared to negative control (NC) group by Flow cytometry. Prediction software and Luciferase experiment demonstrated that hsa-miR-146a directly bound with the 3’UTR of TRAF6, IRAKI; hsa-miR-146a inhibited the expression of TRAF6, IRAK1 by Western Blot. MTT assay results showed that accompanying with the increasing dosage of TRAIL, the viability of cell decreased significantly, the viability of hsa-miR-146a significantly lower than that of the negative control (NC) group; Hoechst staining showed that the apoptosis rate of prostate cancer cells in the application of TRAIL interference after hsa-miR-146a transfection, was significantly higher than that in the negative control (NC) group.Conclusion:The above results suggested that the expression level of hsa-miR-146a in castration-resistant prostate cancer was low. And significantly induced the apoptosis of prostate cancer. TRAF6, IRAK1 was the potential target gene of hsa-miR-146a. hsa-miR-146a inhibited the expression of its target genes and promoted the apoptosis of prostate cancer cells; TRAIL promoted the apoptosis of prostate cancer cells, and the hsa-miR-146a enhanced the sensitivity of TRAIL.