Aims: This study is to investigate the role of miR-25 in pediatric neuroblastoma.
Methods: The expression of miR-25 in pediatric neuroblastoma tissues and cell lines was determined by quantitative PCR. SH-SY5Y and IMR32 cells were transfected with miR-25 mimics and inhibitor, respectively. The effect of miR-25 on pediatric neuroblastoma was analysed by CCK-8 assay, flow cytometry and Transwell assay. Western blot was performed to detect the protein expression of TOB1, a potential target gene of miR-25. Dual luciferase reporter assay was carried out to determine the direct binding between miR-25 and TOB1.
Results: The expression of miR-25 was upregulated in pediatric neuroblastoma tissues and positively correlated to distant metastasis and clinical stages. The expression of miR-25 in the metastases derived SH-SY5Y cells was higher than that in the primary tumor derived IMR32 cells. In vitro experiments showed that over expression of miR-25 promoted the proliferation, G1/S phase transition and metastasis of IMR32 cells, while down regulation of miR-25 inhibited the proliferation, G1/S phase transition and metastasis of SH-SY5Y cells. Upregulation of miR-25 decreased the expression of TOB1 in IMR32 cells, while down-regulation of miR-25 increased the expression of TOB1 in SH-SY5Y cells. Dual luciferase reporter assay confirmed that miR-25 could bind to the 3’-UTR of TOB1, indicating that TOB1 is the direct target gene of miR-25.
Conclusions: The miR-25 expression in neuroblastoma and neuroblastoma cells is upregulated. MiR-25 can promote the proliferation, invasion and metastasis of neuroblastoma cells by regulating TOB1 expression.