Upregulation lnc-NEAT1 contributes to colorectal cancer progression through sponging miR-486-5p and activating NR4A1/Wnt/β-catenin pathway

Abstract

Colorectal cancer is a major public health problem and fourth guiding cause of cancer-induced mortality worldwide. The five-year survival rate for patients with colorectal cancer remains poor, and almost half of colorectal cancer patients present recurrence and die within five years. The increasing studies showed that long non-coding RNA (lncRNA) was involved in colorectal cancer. Therefore, this study was used to explore molecular mechanisms of nuclear paraspeckle assembly transcript 1 (NEAT1) in colorectal cancer. The real-time quantitative polymerase chain reaction (RT-qPCR) was employed to estimate the expression levels of NEAT1, Nuclear receptor 4 A1 (NR4A1), and miR-486-5p in colorectal cancer tissues and cells. Kaplan-Meier curve was conducted to analyze relationship between survival time of colorectal cancer patients and level of NEAT1. The protein levels of NR4A1, β-catenin, c-Myc, and cyclinD1 were assessed with western blot assay. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT) and flow cytometry assays were performed to evaluate proliferation and apoptosis of colorectal cancer cells, respectively. The migration and invasion abilities of cells were examined by transwell assay. The relationship between miR-486-5p and NEAT1 or NR4A1 was confirmed by dual-luciferase reporter assay. We found NEAT1 and NR4A1 were highly expressed in colorectal cancer tissues and cell lines compared with controls. Loss-functional experiments revealed that knockdown of NEAT1 or NR4A1 repressed proliferation and motility, while inducing apoptosis of colorectal cancer cells. The gain of NR4A1 could abolish NEAT1 silencing-induced effects in colorectal cancer cells. In addition, NEAT1 contributed to colorectal cancer progression through mediating NR4A1/Wnt/β-catenin signaling pathway. In conclusion, NEAT1 stimulated colorectal cancer progression via acting as competing endogenous RNA to sponge miR-486-5p and regulate NR4A1/Wnt/β-catenin signaling pathway.