Department of Otorhinolaryngology, The First Affiliated Hospital of Zhengzhou University, Jianshe Dong Road No.1, Zhengzhou, 450052, China.
Department of Otorhinolaryngology, The First Affiliated Hospital of Zhengzhou University, Jianshe Dong Road No.1, Zhengzhou, 450052, China.
Biochimie. 2018 Sep;152:63-72. doi: 10.1016/j.biochi.2018.06.015. Epub 2018 Jun 26.
The roles and mechanisms of long non-coding RNAs (lncRNA) in nasopharyngeal carcinoma (NPC) cells stemness and chemotherapeutic sensitivity are unclear. Here, Quantitative real-time PCR (qRT-PCR) was performed to detect the lncRNA THOR expression in NPC and normal adjacent tissues, adherent NPC cells and non-adherent NPC spheres, and we found that THOR was significantly increased in NPC tissues and non-adherent NPC spheres. Further in vitro and in vivo experiments were carried out and identified that knockdown of THOR attenuated NPC cells stemness, characterized as the decrease of spheres formation ability, cell proliferation, migration, invasion, stemness markers expression and tumor initiation, and enhanced cisplatin sensitivity of NPC cells. Mechanistically, RNA immunoprecipitation (RIP), immunofluorescence and luciferase reporter analysis indicated that THOR could enhance YAP transcriptional activity via directly binding to YAP and suppressing its translocation from nuclear to cytoplasm. Notably, overexpression of YAP rescued the inhibition of THOR knockdown on NPC cells and spheres stemness and promotion on cisplatin sensitivity. Thus, our results demonstrate that lncRNA THOR could attenuate cisplatin sensitivity of NPC cells by enhancing cells stemness through promoting YAP transcriptional activity.
长链非编码 RNA（lncRNA）在鼻咽癌（NPC）细胞干性和化疗敏感性中的作用和机制尚不清楚。在这里，我们通过定量实时 PCR（qRT-PCR）检测 NPC 和正常相邻组织、贴壁 NPC 细胞和非贴壁 NPC 球体中的 lncRNA THOR 表达，发现 THOR 在 NPC 组织和非贴壁 NPC 球体中显著增加。进一步进行了体外和体内实验，结果表明，THOR 的敲低减弱了 NPC 细胞的干性，表现为球体形成能力、细胞增殖、迁移、侵袭、干性标志物表达和肿瘤起始能力下降，并增强了 NPC 细胞对顺铂的敏感性。机制上，RNA 免疫沉淀（RIP）、免疫荧光和荧光素酶报告分析表明，THOR 可以通过直接结合 YAP 并抑制其从核内到细胞质的易位来增强 YAP 的转录活性。值得注意的是，YAP 的过表达挽救了 THOR 敲低对 NPC 细胞和球体干性的抑制作用，并促进了顺铂敏感性。因此，我们的结果表明，lncRNA THOR 通过增强 YAP 的转录活性来减弱 NPC 细胞对顺铂的敏感性。
