Sakaguchi Takashi, Yoshino Hirofumi, Yonemori Masaya, Miyamoto Kazutaka, Sugita Satoshi, Matsushita Ryosuke, Itesako Toshihiko, Tatarano Shuichi, Nakagawa Masayuki, Enokida Hideki
Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan.
Br J Cancer. 2017 Apr 11;116(8):1077-1087. doi: 10.1038/bjc.2017.43. Epub 2017 Mar 21.
Based on the microRNA (miRNA) signature of bladder cancer (BC) by deep sequencing, we recently found that several double-stranded mature miRNAs derived from the same pre-miRNAs were sufficiently expressed and acted as tumour suppressors by regulating common target genes in BC. Our deep-sequencing signature of BC showed that all miR-199 family members (miR-199a-3p/-5p and miR-199b-3p/-5p) were also downregulated. We hypothesised that these miRNAs may function as tumour suppressors by regulating common target genes.
Functional assays of BC cells were performed using transfection of mature miRNA. In silico analyses and luciferase reporter analyses were applied to identify target genes of these miRNAs. The overall survival of patients with BC in The Cancer Genome Atlas (TCGA) database was evaluated by the Kaplan-Meier method.
Restoration of these miRNAs significantly inhibited cell migration and invasion in BC cells. Integrin α3 (ITGA3) was directly regulated by these miRNAs. The Cancer Genome Atlas database showed that patients with low pre-miR-199 family (miR-199a-1/-2 and miR-199b) expression exhibited significantly poorer overall survival compared with patients with high pre-miR-199 family expression.
miR-199 family miRNAs functioned as tumour suppressors in BC cells by targeting ITGA3 and might be good prognostic markers for predicting survival in patients with BC.
基于通过深度测序得到的膀胱癌（BC）的微小RNA（miRNA）特征，我们最近发现，源自相同前体miRNA的几种双链成熟miRNA在BC中充分表达，并通过调控共同的靶基因发挥肿瘤抑制作用。我们的BC深度测序特征显示，所有miR-199家族成员（miR-199a-3p/-5p和miR-199b-3p/-5p）也下调。我们推测这些miRNA可能通过调控共同的靶基因发挥肿瘤抑制作用。
使用成熟miRNA转染进行BC细胞的功能分析。应用计算机分析和荧光素酶报告基因分析来鉴定这些miRNA的靶基因。通过Kaplan-Meier方法评估癌症基因组图谱（TCGA）数据库中BC患者的总生存期。
这些miRNA的恢复显著抑制了BC细胞的迁移和侵袭。整合素α3（ITGA3）受这些miRNA直接调控。癌症基因组图谱数据库显示，与前体miR-199家族（miR-199a-1/-2和miR-199b）高表达的患者相比，前体miR-199家族低表达的患者总生存期显著更差。
miR-199家族miRNA通过靶向ITGA3在BC细胞中发挥肿瘤抑制作用，可能是预测BC患者生存的良好预后标志物。
