PUM2, an RNA binding protein, is known to promote stem cell proliferation via repressing expressions of cell cycle genes. Similar with stem cells, malignant cells are characterized by unlimited proliferation and remote migration. However, roles of PUM2 in cancer development are controversial. Here, we investigated PUM2's role in glioblastoma development and its relationship with the cell cycle regulator BTG1. Immunoblotting and RT-qPCR were used to evaluate protein expression level and transcript level, respectively. ShRNAs were designed to knock down PUM2 and BTG1 expression. CCK-8 assay was used to evaluate cell viability. Cell migration assay and evasion assay were used to evaluate metastatic capability of glioblastoma cell. RNA pull-down assay and RNA immunoprecipitation assay were used to test the interaction between PUM2 and BTG1 3'UTR. PUM2 expression is elevated in glioblastoma tumor tissues as well as glioblastoma cell lines. PUM2 knockdown remarkably suppresses glioblastoma cell proliferation and migration. In addition, PUM2 knockdown increases BTG1 expression. RNA pull-down assay and RNA immunoprecipitation assay show PUM2 binds to BTG1 3'UTR directly. Furthermore, knockdown of BTG1 reverses the effect of PUM2 knockdown on glioblastoma cell proliferation and migration. Our results suggest that PUM2 promote glioblastoma development via repressing BTG1 expression.Key words: PUM2, BTG1, glioblastoma, cell proliferation, metastasis.

中文翻译：

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PUM2通过抑制BTG1表达促进胶质母细胞瘤细胞的增殖和迁移。

已知RNA结合蛋白PUM2通过抑制细胞周期基因的表达来促进干细胞增殖。与干细胞相似，恶性细胞的特征是无限增殖和远距离迁移。然而，PUM2在癌症发展中的作用是有争议的。在这里，我们调查了PUM2在胶质母细胞瘤发展中的作用及其与细胞周期调节剂BTG1的关系。免疫印迹和RT-qPCR分别用于评估蛋白质表达水平和转录水平。ShRNA被设计为敲低PUM2和BTG1表达。使用CCK-8测定来评估细胞活力。细胞迁移分析和逃避分析用于评估胶质母细胞瘤细胞的转移能力。RNA下拉实验和RNA免疫沉淀实验用于测试PUM2和BTG1 3'之间的相互作用 UTR。在胶质母细胞瘤肿瘤组织和胶质母细胞瘤细胞系中，PUM2表达升高。PUM2基因敲低显着抑制胶质母细胞瘤细胞增殖和迁移。此外，PUM2组合式增加BTG1表达。RNA下拉分析和RNA免疫沉淀分析显示PUM2直接与BTG1 3'UTR结合。此外，敲除BTG1可逆转PUM2敲除对胶质母细胞瘤细胞增殖和迁移的影响。我们的研究结果表明，PUM2通过抑制BTG1的表达促进胶质母细胞瘤的发展。关键词：PUM2，BTG1，胶质母细胞瘤，细胞增殖，转移。RNA下拉分析和RNA免疫沉淀分析显示PUM2直接与BTG1 3'UTR结合。此外，敲除BTG1可逆转PUM2敲除对胶质母细胞瘤细胞增殖和迁移的影响。我们的研究结果表明，PUM2通过抑制BTG1的表达促进胶质母细胞瘤的发展。关键词：PUM2，BTG1，胶质母细胞瘤，细胞增殖，转移。RNA下拉分析和RNA免疫沉淀分析显示PUM2直接与BTG1 3'UTR结合。此外，敲除BTG1可逆转PUM2敲除对胶质母细胞瘤细胞增殖和迁移的影响。我们的研究结果表明，PUM2通过抑制BTG1的表达促进胶质母细胞瘤的发展。关键词：PUM2，BTG1，胶质母细胞瘤，细胞增殖，转移。