The First Department of General Surgery, Affiliated Hospital of Chengde Medical University, Chengde 067000, P.R. China.
The First Department of Gynecology, Affiliated Hospital of Chengde Medical University, Chengde 067000, P.R. China.
Biochem J. 2020 Sep 30;477(18):3527-3540. doi: 10.1042/BCJ20200219.
Cholangiocarcinoma (CCA) has accounted for a high rate of mortality and morbidity in the recent years. Long non-coding RNAs (lncRNAs) play an important role in different cellular environments, including cancer. As such, they have been used as potential targets during CCA therapy. The objective of this study was to investigate the effects of lncRNA PVT1 on CCA and its mechanisms behind lncRNA PVT1 regulation. The interactions among SOX2, lncRNA PVT1, miR-186 and SEMA4D were verified by chromatin immunoprecipitation, RNA immunoprecipitation and dual luciferase reporter gene assay. Gain- and loss-of-function experiments were conducted to explore the modulatory effects of SOX2, lncRNA PVT1, miR-186 and SEMA4D on cell viability, migration and invasion of CCA by CCK-8 and Transwell assays. In vivo effects of lncRNA PVT1 or SEMA4D were studied in a nude mouse model. MiR-186 was poorly expressed while SOX2, lncRNA PVT1 and SEMA4D were highly expressed in CCA cells. SOX2 induced the transcriptional activation of lncRNA PVT1 expression to promote proliferation, migration and invasion of CCA cells. LncRNA PVT1 bound to miR-186 and miR-186 was found to target SEMA4D. The overexpression of lncRNA PVT1 and SEMA4D, as well as the inhibition of miR-186 led to elevated CCA cell proliferation, migration and invasion. In vivo experiments confirmed the inhibitory role of lncRNA PVT1 knockdown or SEMA4D knockdown in CCA. All in all, SOX2 down-regulated miR-186 through the transcriptional activation of lncRNA PVT1, whereas elevating SEMA4D expression, thus promoting the progression of CCA.
胆管癌（CCA）近年来的死亡率和发病率居高不下。长链非编码 RNA（lncRNA）在不同的细胞环境中发挥着重要作用，包括癌症。因此，它们已被用作 CCA 治疗的潜在靶点。本研究旨在探讨 lncRNA PVT1 对 CCA 的影响及其调控 lncRNA PVT1 的机制。通过染色质免疫沉淀、RNA 免疫沉淀和双荧光素酶报告基因检测验证了 SOX2、lncRNA PVT1、miR-186 和 SEMA4D 之间的相互作用。通过 CCK-8 和 Transwell 测定进行了 gain-和 loss-of-function 实验，以探讨 SOX2、lncRNA PVT1、miR-186 和 SEMA4D 对 CCA 细胞活力、迁移和侵袭的调节作用。在裸鼠模型中研究了 lncRNA PVT1 或 SEMA4D 的体内作用。miR-186 在 CCA 细胞中表达水平较低，而 SOX2、lncRNA PVT1 和 SEMA4D 表达水平较高。SOX2 诱导 lncRNA PVT1 的转录激活，促进 CCA 细胞的增殖、迁移和侵袭。lncRNA PVT1 与 miR-186 结合，miR-186 被发现靶向 SEMA4D。lncRNA PVT1 和 SEMA4D 的过表达以及 miR-186 的抑制导致 CCA 细胞增殖、迁移和侵袭的增加。体内实验证实了 lncRNA PVT1 敲低或 SEMA4D 敲低在 CCA 中的抑制作用。总之，SOX2 通过转录激活 lncRNA PVT1 下调 miR-186，从而升高 SEMA4D 表达，从而促进 CCA 的进展。
