Knockdown of UHRF1 by Lentivirus-mediated shRNA Inhibits Ovarian Cancer Cell Growth

Abstract

Human UHRF1 (ubiquitin-like PHD and RING finger domain-containing 1) has been reported to beover-expressed in many cancers, but its role in ovarian cancer remains elusive. Here, we determined whetherknockdown of UHRF1 by lentivirus-mediated shRNA could inhibit ovarian cancer cell growth. Lentivirusmediatedshort hairpin RNAs (lv-shRNAs-UHRF1) were designed to trigger the gene silencing RNA interference(RNAi) pathway. The efficiency of lentivirus-mediated shRNA infection into HO-8910 and HO-8910 PM cells wasdetermined using fluorescence microscopy to observe lentivirus-mediated GFP expressionand was confirmed to beover 80 percent. UHRF1 expression in infected HO-8910 and HO-8910 PM was evaluated by real-time PCR andWestern blot analysis. The Cell Counting Kit-8 (CCK-8) assay was used to measure cell viability; flow cytometryand Hoechst 33342 assay was applied to measure cell cycle arrest and apoptosis. Cell invasion was assessedusing transwell chambers. Our results demonstrated that the loss of UHRF1 promoted HO-8910 and HO-8910PM cell apoptosis, while inhibiting cell proliferation. In addition, UHRF1 knockdown significantly inhibitedthe invasion of human ovarian cancer cells. In the present study, we also showed that depleting HO-8910 cellsof UHRF1 caused activation of the DNA damage response pathway, with the cell cycle arrested in G2/M-phase.The DNA damage response in cells depleted of UHRF1 was illustrated by phosphorylation of CHK (checkpointkinase) 2 on Thr68, phosphorylation of CDC25 (cell division control 25) on Ser 216 and phosphorylation ofCDK1 (cyclin-dependent kinase 1) on Tyr 15.