YAF2靶向cyclinD1表达促进肿瘤细胞增殖

YAF2 promotes tumor cell proliferation via targeting cyclin D1 expression

目的研究YY1相关因子2(YAF2)在肿瘤细胞中上调细胞周期蛋白D1(cyclin D1)表达的分子机制以及对肿瘤细胞增殖的影响。方法在肿瘤细胞中过表达和敲低YAF2,用Western blot和实时荧光定量PCR实验检测YAF2和cyclin D1的表达;利用双荧光素酶报告基因实验探究YAF2对cyclin D1启动子活性的影响;流式细胞计量术分析YAF2对细胞周期的影响与cyclin D1表达的关系;平板克隆形成实验检测YAF2和cyclin D1不同表达水平对细胞增殖的影响。结果 YAF2上调cyclin D1的mRNA(P<0.05)和蛋白水平;YAF2激活cyclin D1的启动子(P<0.05);敲低YAF2通过调节cyclin D1使G_0/G_1期细胞比例增加(P<0.0001),S期细胞比例减少(P<0.002);YAF2通过靶向cyclin D1促进细胞克隆形成(P<0.05)。结论在肿瘤细胞中,YAF2激活cyclin D1表达,促进肿瘤细胞周期进展和增殖。

Objective To explore the molecular mechanism by which YY1 associated factor 2（ YAF2） up-regulates cyclin D1 expression in tumor cells as well as the effect of YAF2-cyclin D1 regulatory loop on tumor cell proliferation. Methods Overexpression and knockdown experiments combined with Western blot and real-time quantitative PCR were used to detect the expression of YAF2 and cyclin D1; Dual luciferase reporter assay was performed to investigate the effect of YAF2 on cyclin D1 promoter activity; Flow cytometry analysis was carried out to elucidate the effect of YAF2 on cell cycle progression through targeting cyclin D1; Colony formation assay was employed to determine cell proliferation under different YAF2 and cyclin D1 expression level. Results YAF2 upregulated the expression of cyclin D1 at both the mRNA（ P〈0. 05） and protein level; YAF2 activated the promoter activity of cyclin D1（ P〈0. 05）; YAF2 silencing increased significantly the proportion of cells in G0/G1 phase（ P〈0. 0001） and reduced the proportion of cells in S phase by regulating cyclin D1（ P 0. 002）; YAF2 facilitated the cell colony formation via targeting cyclin D1（ P〈0. 05）. Conclusions In tumor cells,YAF2 promotes the expression of cyclin D1,and enhances cell cycle progression and cell proliferation.