MiR-155-5p affects Wilms' tumor cell proliferation and apoptosis via targeting CREB1.

OBJECTIVE: The aim of this study was to explore the role of microRNA-155-5p (miR-155-5p) in regulating the proliferation and apoptosis of Wilm's tumor (WT). and to investigate the possible underlying mechanism. PATIENTS AND METHODS: The expression levels of miR-155-5p in 37 pairs of WT clinical samples, as well as WT cell line (G401), were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay and flow cytometry assay were used to detect the effects of miR-155-5p on cell proliferation, cycle and apoptosis. Target gene prediction software was applied to screen the potential downstream target gene of miR-155-5p. QRT-PCR, Western blot (WB) and luciferase reporter gene assay proved that CAMP-response element binding protein 1 (CREB1) was the target gene of miR-155-5p. Besides, rescue experiment was conducted to further explore the effect of CREB1 on WT cells. RESULTS: The expression levels of miR-155-5p in WT tissues and cells were both significantly down-regulated. Importantly. miR-155-5p was found to be involved in the malignant behavior of WT cells. MTT assay and flow cytometry assay demonstrated that miR-155-5p significantly inhibited the proliferation, caused stagnation of cells in G0/G1 phase, and promoted cell apoptosis. CREB1 was verified as a functional target gene of miR-155-5p, which was negatively regulated by miR-155-5p. Rescue experiments indicated that restoring the expression of CREB1 could interfere with the effects of miR-155-5p on WT cells. CONCLUSIONS: MiR-155-5p could regulate the proliferation. cell cycle and apoptosis of WT cells. These effects were achieved by regulating the expression of CREB1. Furthermore, our study might provide a new theoretical basis for the basic research of WT.