lncRNA NEAT1调控miR-4262表达影响甲状腺癌细胞增殖、迁移和侵袭的机制研究

Mechanism of lncRNA NEAT1 regulating the expression of miR-4262 affecting the proliferation,migration and invasion of thyroid cancer cells

目的:研究长链非编码RNA NEAT1(lncRNA NEAT1)对甲状腺癌细胞增殖、迁移和侵袭的影响及其作用机制。方法:qPCR检测NEAT1和miR-4262在人正常甲状腺滤泡上皮细胞株Nthy-ori 3-1与甲状腺癌细胞株FTC-133、ML-1、SW579中的表达。用si-NEAT1或miR-4262 mimic转染SW579细胞,考察其在细胞增殖、迁移和侵袭中的作用。生物学信息预测结合双荧光素酶报告实验分析NEAT1和miR-4262之间的靶向关系。MTT法检测细胞增殖抑制率;Western blot检测细胞周期蛋白D1(CyclinD1)、p21、基质金属蛋白酶-2(MMP-2)和基质金属蛋白酶-9(MMP-9)表达;Transwell小室法检测细胞迁移和侵袭。共转染si-NEAT1和anti-miR-4262,观察抑制miR-4262表达对抑制NEAT1表达诱导的SW579细胞增殖、迁移及侵袭的影响。结果:NEAT1在甲状腺癌细胞中的表达显著上调(P<0.05),miR-4262表达下调(P<0.05)。抑制NEAT1表达或过表达miR-4262显著增加SW579细胞增殖抑制率和p21蛋白表达量(P<0.05),显著降低迁移细胞数、侵袭细胞数及Cyclin D1、MMP-2和MMP-9蛋白表达量(P<0.05)。miR-4262是NEAT1的靶基因。上调或下调NEAT1表达明显调控miR-4262表达(P<0.05)。抑制miR-4262表达能逆转抑制NEAT1表达对SW579细胞增殖抑制率和p21蛋白表达的促进作用,以及对细胞迁移、侵袭及Cyclin D1、MMP-2和MMP-9蛋白表达的抑制作用。结论:lncRNA NEAT1通过靶向miR-4262影响甲状腺癌细胞增殖、迁移和侵袭。

Objective:To study the effects of long non-coding RNA NEAT1(lncRNA NEAT1)on proliferation,migration and invasion of thyroid cancer cells and its mechanism.Methods:The expression of NEAT1 and miR-4262 in human normal thyroid follicular epithelial cell lines Nthy-ori 3-1 and thyroid cancer cell lines FTC-133,ML-1 and SW579 were detected by qPCR.SW579 cells were transfected with si-NEAT1 or miR-4262 mimic to investigate their role in cell proliferation,migration and invasion.Bioinformatics prediction and dual luciferase reporter assay were used to analyze the targeting relationship between NEAT1 and miR-4262.MTT assay was used to determine the inhibition rate of cell proliferation.Western blot was applied to analyze the expression of CyclinD1(CyclinD1),p21,matrix metalloproteinase-2(MMP-2)and matrix metalloproteinase-9(MMP-9).Transwell assay was employed to test cell migration and invasion.si-NEAT1 and anti-miR-4262 were co-transfected to observe the effects of inhibiting miR-4262 expression on the proliferation,migration and invasion of SW579 cells induced by inhibiting NEAT1 expression.Results:The expression of NEAT1 was significantly up-regulated in thyroid cancer cells(P<0.05),and the expression of miR-4262 was down-regulated(P<0.05).Inhibition of NEAT1 expression or over-expression of miR-4262 obviously increased the inhibition rate of proliferation and the expression of p21 protein in SW579 cells(P<0.05),while remarkably decreased the number of migrating cells and invasive cells and the expression of CyclinD1,MMP-2 and MMP-9 protein(P<0.05).miR-4262 was the target gene of NEAT1.Up-regulation or down-regulation of NEAT1 expression significantly regulated the expression of miR-4262(P<0.05).Inhibiting the expression of miR-4262 reversed the promotion effects of inhibiting NEAT1 expression on the proliferation inhibition rate and p21 protein expression of SW579 cells,as well as the inhibition of cell migration,invasion and the expression of CyclinD1,MMP-2 and MMP-9 protein.Conclusion:lncRNA NEAT1 affects the proliferation,migration and invasion of thyroid cancer cells by targeting miR-4262.