MicroRNA-504 targets AEG-1 and inhibits cell proliferation and invasion in retinoblastoma

The dysregulation of microRNAs (miRNAs/miRs) has become increasingly recognized as a primary feature of retinoblastoma (RB). Furthermore, miRNAs have been demonstrated to be involved in the occurrence and development of RB. Therefore, it is crucial to investigate the expression profile and roles of miRNAs in RB in order to identify potential therapeutic targets to treat patients with RB. The expression profile and biological roles of miRNA-504 (miR-504) have been reported in numerous types of human cancer; however, the roles of miR-504 in RB remain unknown. In the present study, it was demonstrated that miR-504 expression was significantly decreased in RB tissues and cell lines. Functional analysis identified that resumption of miR-504 expression suppressed cell proliferation and invasion in RB. Furthermore, astrocyte elevated gene-1 (AEG-1) was determined to be a direct target of miR-504 in RB, and a negative correlation between miR-504 and AEG-1 mRNA expression levels was observed in RB tissues. Additionally, the tumor-suppressing effects of miR-504 overexpression in RB cells could be rescued by AEG-1 upregulation. In conclusion, these results indicated a significant role of the miR-504/AEG-1 pathway in inhibiting the aggressiveness of RB, suggesting that this miRNA may be employed as a therapeutic target for the treatment of patients with this disease.