Silencing UHRF1 Inhibits Cell Proliferation and Promotes Cell Apoptosis in Retinoblastoma Via the PI3K/Akt Signalling Pathway

This study aimed to investigate the effect of silencing ubiquitin-like with PHD and RING finger domains 1 (UHRF1) on the proliferation and apoptosis of retinoblastoma (RB) cells and to clarify the molecular mechanism of the UHRF1 gene in the development of RB. Human RB WERI-Rb-1 cells were selected and assigned into a blank group (WERI-Rb-1 cells with no transfection), NC-shRNA group (WERI-Rb-1 cells infected with NC-shRNA virus) and UHRF1-shRNA group (WERI-Rb-1 cells infected with pGC-UHRF1-shRNA-LV-GFP# (39-1) virus). The mRNA and protein expression of UHRF1 was detected by RT-qPCR and Western blot analysis. The effect of silencing UHRF1 on the proliferation and apoptosis of WERI-Rb-1 cells was assessed by MTT assay, EdU assay, flow cytometry, and Hoechst staining. Furthermore, the expression of cell cycle-related factor (cyclin D1), apoptosis-related factors (caspase-9, Bcl-2 and Bax), and PI3K/Akt signalling pathway-related factors (p-PI3K, PI3K, p-Akt and Akt) were measured via Western blot analysis. The RNA interference plasmid UHRF1-shRNA was successfully constructed. After WERI-Rb-1 cells were infected with UHRF1-shRNA, decreased mRNA and protein expression of UHRF1 was found. WERI-Rb-1 cells infected with UHRF1-shRNA showed inhibited proliferative ability and increased apoptosis. In the UHRF1-shRNA group, more cells arrested at the G0/G1 phase and less cells at the S and G2/M phases. WERI-Rb-1 cells infected with UHRF1-shRNA had increased expression of caspase-9 and Bax and decreased expression of Bcl-2 expression and decreased levels of p-PI3K and p-Akt. In conclusion, our study demonstrated that silencing UHRF1 could inhibit the proliferation of RB cells and promote apoptosis. The mechanism may be caused by the downregulation of the proportion of Bcl-2/Bax expression and the promotion of the expression of caspase-9 through the PI3K/Akt signalling pathway.