lncRNA NEAT1 promotes cell proliferation of lung adenocarcinoma PC-9 cells through inhibiting DNAdamage / 中国肿瘤生物治疗杂志

ABSTRACT

@# Objective: To investigate the effects of long non-coding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) on the proliferation of lung adenocarcinoma PC-9 cells and to explore its mechanism. Methods: qPCR was used to detect the expression level of lncRNA NEAT1 in human lung adenocarcinoma PC-9 cells and human embryonic lung diploid 2BS cells. The sequence of small interfering RNA(siRNA) targeting lncRNANEAT1 gene was designed and synthesized, and then transfected into PC-9 cells by liposome method. The expression level of NEAT1 in PC-9 cells before and after transfection was detected by qPCR. MTT and flow cytometry were used to detect the effect of lncRNANEAT1 knockdown on proliferation and cell cycle distribution of PC-9 cells, respectively. WB assay was used to detect the expressions of DNA damage-related proteins, namely, double-stranded DNA breaks (DSBs) biomarker γ-H2AX and ataxia-telangiectasia mutated (ATM), before and after transfection. Results: Compared with 2BS cells, lncRNA NEAT1 was highly expressed in PC-9 cells (P<0.05). The PC-9 cells with lncRNA NEAT1 knock-down were successfully established. After being transfected with siRNA for 12 h, the proliferation of PC-9 cells in siNEAT1 group and siNEAT2 group significantly decreased as compared with the blank control group and the empty transfection group (P<0.05). In the interference groups, cell cycle was arrested in G1 phase ([88.97±2.64]%, [88.15±1.48]% vs [84.5±1.72]%, P<0.05) and G2/M phase ([8.35±2.02]%, [8.11± 1.36]% vs [4.28±1.28]%, P<0.05). The expression levels of DNA damage-related proteinsATM and γ-H2AX in the interference groups were significantly increased (all P<0.05). Conclusion: lncRNA NEAT1 is highly expressed in lung adenocarcinoma PC-9 cells. lncRNA NEAT1 inhibits DNA damage and causes cell cycle at G1/M phase switch, and thus promotes the proliferation of lung adenocarcinoma cells.