miR-9对SGC-7901胃癌细胞株侵袭能力的影响

目的探讨miR-9表达对SGC-7901胃癌细胞株侵袭力的影响及其可能的作用机制。 方法培养SGC-7901胃癌细胞株，分组转染miR-9阴性对照（miR-9 NC）、miR-9模拟物（miR-9 mimics）和miR-9抑制剂（miR-9 inhibitor），上调或下调细胞中miR-9表达水平。采用Transwell实验评价胃癌细胞侵袭能力，应用SYBR Green荧光实时定量聚合酶链反应和Western blot实验检测SGC-7901细胞中MMP-2 mRNA和蛋白表达水平。对miR-9空白对照组、miR-9 mimics组和miR-9 inhibtor组miR-9的相对表达量、MMP-2 mRNA及蛋白相对表达量，Transwell侵袭实验SGC-7901细胞中侵袭细胞数量，多组间均数比较采用单因素方差分析。 结果与空白对照组SGC-7901细胞miR-9的相对表达量比较：转染miR-9 mimics组SGC-7901细胞miR-9的相对表达量明显上升，差异具有统计学意义［（1.002±0.083）vs（15.375±3.097），P=0.012］；转染miR-9 inhibitor组SGC-7901细胞miR-9的相对表达量明显下降，差异具有统计学意义［（1.002±0.083）vs（0.279±0.039），P=0.022］。与空白对照组SGC-7901细胞中侵袭细胞数量比较：转染miR-9 mimics组SGC-7901细胞中侵袭细胞数量明显减少，差异具有统计学意义［（72.0±2.2）vs（23.6±4.2），P=0.026］；转染miR-9 inhibitor组SGC-7901细胞中侵袭细胞数量明显增加，差异具有统计学意义［（72.0±2.2）vs（102.4±7.6），P=0.037］。与空白对照组SGC-7901细胞中MMP-2的mRNA及蛋白的相对表达量比较：miR-9 mimics组SGC-7901细胞中MMP-2的mRNA及蛋白相对表达量明显下降，差异具有统计学意义［（1.006±0.133）vs（0.371±0.132），P=0.011；（0.573±0.063）vs（0.261±0.159），P=0.024］；miR-9 inhibitor组SGC-7901细胞中MMP-2的mRNA及蛋白相对表达量明显上升，差异具有统计学意义［（1.006±0.133）vs（2.995±0.701），P=0.015；（0.573±0.063）vs （0.708±0.079），P=0.016］。 结论在SGC-7901胃癌细胞株中，miR-9可下调MMP-2的表达，抑制细胞的侵袭能力。

Effect of miR-9 on invasion of human gastric cancer SGC-7901 cells

ObjectiveTo investigate the effect of miR-9 expression on the invasion of human gastric cancer cell line SGC-7901 and the possible mechanism involved. MethodsHuman SGC-7901 cells were cultured and transfected with miR-NC, miR-9 mimic, or miR-9 inhibitor for up-regulation or down-regulation of miR-9 expression. Transwell assay was used to evaluate the change of invasive ability. SYBR Green fluorescence quantitative PCR and Western blot were performed to examine the expression of MMP-2. ResultsCompared with the blank control group, the expression of miR-9 in SGC-7901 cells in the miR-9 mimic group was significantly increased (1.002±0.083) vs (15.375±3.097), P=0.012 ], and the expression of miR-9 in the miR-9 inhibitor group was significantly decreased (1.002±0.083) vs (0.279±0.039), P=0.022]. Compared with the blank control group, the number of invasive cells in the miR-9 mimic group was significantly reduced (72.0±2.2) vs (23.6±4.2), P=0.026], and the number of invasive cells in the miR-9 inhibitor group was significantly increased (72.0±2.2) vs (102.4±7.6), P=0.037]. In comparison with the blank control group, the mRNA and protein expression of MMP-2 was significantly decreased (1.006±0.133) vs (0.371±0.132), P=0.011; (0.573±0.063) vs (0.261±0.159), P=0.024] in SGC-7901 cells in the miR-9 mimic group, and the mRNA and protein expression of MMP-2 was significantly increased (1.006±0.133) vs (2.995±0.701), P=0.015; (0.573±0.063) vs (0.708±0.079), P=0.016] in the miR-9 inhibitor group. ConclusionIn human gastric cancer cell line SGC-7901, miR-9 can down-regulate the expression of MMP-2 and inhibit the invasive ability of the cells.