Evaluation of Potential of Long Noncoding RNA NEAT1 in Colorectal Cancer.

Abstract

Long noncoding RNAs (lncRNAs) have been reported to be involved in cancer initiation and evolution, including colorectal cancer (CRC). Nuclear-enriched abundant transcript 1 (NEAT1) exerts important functions in multiple cancers; however, the specific modulatory mechanism in CRC demands in-depth exploration. The expression levels of NEAT1, microRNA-195-5p (miR-195-5p), and centrosomal protein 55 (CEP55) were examined using quantitative real-time polymerase chain reaction (qRT-PCR), and protein expression of CEP55 was detected by Western blot assay. Cell proliferation and apoptosis were measured by 3-(4,5-dimethylthiazole-2-y1)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry. Transwell migration and invasion assays were applied to evaluate cell metastasis ability. Dual-luciferase reporter assay was used to analyze the correlation among NEAT1, miR-195-5p and CEP55. The expression of NEAT1 was up-regulated in CRC tissues and cells, and overall survival was lower with high expression of NEAT1. Knockdown of NEAT1 repressed cell proliferation, migration, and invasion, while inducing apoptosis in CRC cells. NEAT1 targeted miR-195-5p and inhibited the expression of miR-195-5p. Silence of NEAT1 inhibited CRC cell proliferation, migration, and invasion, and promoted apoptosis by up-regulating miR-195-5p. MiR-195-5p targeted and suppressed CEP55 expression, and CEP55 reverted the effects induced by miR-195-5p. NEAT1 regulated the expression of CEP55 through miR-195-5p. NEAT1 promotes colorectal cancer cellular processes by regulating CEP55 expression via the sponging of miR-195-5p. Therefore, NEAT1 might play a crucial role in CRC treatments.