MiRNA-509-5p靶向MDM2抑制胃癌细胞的侵袭和迁移

MiRNA-509-5p inhibits gastric cancer migration and invasion via targeting MDM2

目的明确miRNA-509-5p对胃癌细胞侵袭和迁移的作用并阐明相关的机制。方法实时定量PCR检测miRNA-509-5p在胃癌细胞株及胃癌组织中的表达。对HGC-27细胞株转染miRNA-509-5p模拟物或抑制物后,分别采用CCK-8和Transwell法检测细胞的增殖和迁移。软件预测miRNA-509-5p的靶基因,荧光素酶报告基因验证靶基因。靶基因过表达验证细胞增殖和迁移。结果 miRNA-509-5p在肿瘤组织及细胞株中的表达显著降低。转染miRNA-509-5p模拟物能够显著抑制细胞的增殖、迁移及侵袭。相反,转染miRNA-509-5p抑制物能够显著增加细胞的增殖、迁移及侵袭。此外,miRNA-509-5p能够通过靶向3'-UTR负调控鼠双微体-2(MDM2)。miRNA-509-5p能够显著抑制由MDM2过表达导致的肿瘤细胞增殖、迁移及侵袭。结论 miRNA-509-5p是通过抑制MDM2表达的新型肿瘤抑制子,能够抑制胃癌的增殖、迁移及侵袭。

Objective To explore the role of miRNA-509-5p in gastric cancer and clarify the mechanisms.Methods Real-time PCR was employed to explore the expression of miRNA-509-5p in gastric cancer tissue and cell line.CCK-8 and transwell analysis were respectively employed to examine the cell proliferation and migration after miRNA-509-5p mimic/inhibitor was transfected.Bioinformatic tools were employed to identify the target gene,and cotransfection of the target gene and miRNA-509-5p was used to explore cell migration and proliferation.Results Transfection of miRNA-509-5p mimics significantly inhibited the cell proliferation,migration and invasion in the HGC-27 gastric cancer cell lines.In contrast,knockdown of miRNA-509-5p had the opposite effect on the cell proliferation,migration and invasion.Moreover,we also found that mouse double minute 2 homolog(MDM2) was negatively regulated by miRNA-509-5p at the post-transcriptional level,via a specific target site with 3’ UTR by luciferase reporter assay.The expression of MDM2 was inversely correlated with miRNA-509-5p expression in gastric cancer tissues,and miRNA-509-5p-transfection in gastric cancer cells with MDM2 over-expression effectively rescued the inhibition of cell proliferation and invasion.Conclusions MiRNA-509-5p acts as a new tumor suppressor by targeting the MDM2 gene and inhibiting gastric cancer cell proliferation,migration and invasion.