LncRNA CTD-3252C9.4 modulates pancreatic cancer cell survival and apoptosis through regulating IFI6 transcription

Abstract

Background: Pancreatic cancer (PC) is one of the most lethal cancer types with high degree of malignancy and poor prognosis. Recent studies have shown that long non-coding RNAs (lncRNAs) were associated with the initiation and progression of pancreatic cancer. In the current study, we have investigated the expression, biological function and mechanism of a lncRNA CTD-3252C9.4 in pancreatic cancer. Methods: The expression of CTD-3252C9.4 in pancreatic cancer cells and tissues was measured by qRT-PCR. In vitro and in vivo functional experiments assays were implemented for identifying CTD-3252C9.4 function in pancreatic cancer. Molecular relationships among CTD-3252C9.4, IRF1 and IFI6 were investigated via luciferase reporter assay, pulldown assay and ChIP assays. Results: CTD-3252C9.4 was found remarkably decreased in pancreatic cancer cells and tissues. Overexpression of CTD-3252C9.4 suppressed migration, invasion and proliferation, yet facilitated apoptosis of pancreatic cancer cells both in vitro and in vivo. Then, IFI6 was identified as a downstream target that could be down-regulated by CTD-3252C9.4 and IFI6 overexpression could counteract the effects of CTD-3252C9.4 upregulation on the survival and apoptosis of pancreatic cancer cells. Furthermore, mechanism experiments revealed that IRF1 was a transcriptional factor of IFI6 that can be blocked by CTD-3252C9.4 to inhibit IFI6 transcription. Conclusion: Our data indicated that CTD-3252C9.4 could promote pancreatic cancer cell apoptosis and restrain cell growth via binding IRF1 and preventing the transcription of IFI6, which may become a potential therapeutic target for pancreatic cancer.