Division of Infectious Diseases, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, R I02903, USA, Laboratory of Genetics and Molecular Biology, Division of Physiology, Department of Zoology, Northeast Forestry University, Harbin 150040, China, Key Laboratory of Laboratory Medical Diagnostics, Chinese Ministry of Education, Chongqing Medical University, Chongqing 400016, China and Department of Pathology, Warren Alpert Medical School of Brown University, Providence, RI02903, USA.
Nucleic Acids Res. 2014 Mar;42(5):2988-98. doi: 10.1093/nar/gkt1275. Epub 2013 Dec 13.
Glycogen synthase kinase 3 beta (GSK3β) is a critical protein kinase that phosphorylates numerous proteins in cells and thereby impacts multiple pathways including the β-Catenin/TCF/LEF-1 pathway. MicroRNAs (miRs) are a class of noncoding small RNAs of ∼22 nucleotides in length. Both GSK3β and miR play myriad roles in cell functions including stem cell development, apoptosis, embryogenesis and tumorigenesis. Here we show that GSK3β inhibits the expression of miR-96, miR-182 and miR-183 through the β-Catenin/TCF/LEF-1 pathway. Knockout of GSK3β in mouse embryonic fibroblast cells increases expression of miR-96, miR-182 and miR-183, coinciding with increases in the protein level and nuclear translocation of β-Catenin. In addition, overexpression of β-Catenin enhances the expression of miR-96, miR-182 and miR-183 in human gastric cancer AGS cells. GSK3β protein levels are decreased in human gastric cancer tissue compared with surrounding normal gastric tissue, coinciding with increases of β-Catenin protein, miR-96, miR-182, miR-183 and primary miR-183-96-182 cluster (pri-miR-183). Furthermore, suppression of miR-183-96-182 cluster with miRCURY LNA miR inhibitors decreases the proliferation and migration of AGS cells. Knockdown of GSK3β with siRNA increases the proliferation of AGS cells. Mechanistically, we show that β-Catenin/TCF/LEF-1 binds to the promoter of miR-183-96-182 cluster gene and thereby activates the transcription of the cluster. In summary, our findings identify a novel role for GSK3β in the regulation of miR-183-96-182 biogenesis through β-Catenin/TCF/LEF-1 pathway in gastric cancer cells.
糖原合成酶激酶 3β（GSK3β）是一种关键的蛋白激酶，可磷酸化细胞中的许多蛋白质，从而影响包括β-连环蛋白/TCF/LEF-1 途径在内的多条途径。MicroRNAs（miRs）是一类长度约为 22 个核苷酸的非编码小分子 RNA。GSK3β 和 miR 在包括干细胞发育、细胞凋亡、胚胎发生和肿瘤发生在内的细胞功能中发挥着众多作用。在这里，我们表明 GSK3β 通过β-连环蛋白/TCF/LEF-1 途径抑制 miR-96、miR-182 和 miR-183 的表达。在小鼠胚胎成纤维细胞中敲除 GSK3β 会增加 miR-96、miR-182 和 miR-183 的表达，同时β-连环蛋白的蛋白水平和核转位增加。此外，β-连环蛋白在人胃癌 AGS 细胞中的过表达增强了 miR-96、miR-182 和 miR-183 的表达。与周围正常胃组织相比，人胃癌组织中 GSK3β 蛋白水平降低，同时β-连环蛋白蛋白、miR-96、miR-182、miR-183 和初级 miR-183-96-182 簇（pri-miR-183）增加。此外，用 miRCURY LNA miR 抑制剂抑制 miR-183-96-182 簇的表达会降低 AGS 细胞的增殖和迁移。用 siRNA 敲低 GSK3β 会增加 AGS 细胞的增殖。从机制上讲，我们表明β-连环蛋白/TCF/LEF-1 结合到 miR-183-96-182 簇基因的启动子上，从而激活该簇的转录。总之，我们的研究结果确定了 GSK3β 通过β-连环蛋白/TCF/LEF-1 途径在胃癌细胞中调节 miR-183-96-182 生物发生的新作用。
