MicroRNA-429 inhibits neuroblastoma cell proliferation, migration and invasion via the NF-κB pathway.

Background: MicroRNAs (miRNAs or miRs) can participate in the development and progression of neuroblastoma. Many studies have indicated that miR-429 can participate in tumor development. However, the mechanism underlying miR-429-mediated progression of neuroblastoma remains largely unclear.

Methods: Colony formation and apoptosis assays were used to determine the effect of miR-429 on cell proliferation. Its impact on cell migration was determined using the wound-healing and Transwell assays. The target gene of miR-429 was confirmed via western blotting and luciferase reporter assays. A nude mouse xenograft model with miR-429 overexpression was used to assess the effect on tumor growth.

Results: Our findings indicate that miR-429 is downregulated in neuroblastoma cell lines. We also found that it can induce apoptosis and inhibit proliferation in cells of those lines. MiR-429 can bind to the 3'-UTR of IKKβ mRNA and overexpression of IKKβ can reverse cell proliferation, blocking the effect of miR-429. Furthermore, miR-429 overexpression inhibited neuroblastoma growth in our nude mouse xenograft model.

Conclusion: We provide important insight into miR-429 as a tumor suppressor through interaction with IKKβ, which is a catalytic subunit of the IKK complex that activates NF-κB nuclear transport. Our results demonstrate that miR-429 may be a new target for the treatment of neuroblastoma.