Department of Otolaryngology Head and Neck Surgery, The Second Hospital of Jilin University, Changchun 130041, Jilin, China.
Department of Pharmacy, The Second Hospital of Jilin University, Changchun 130041, Jilin, China.
Cancer Biomark. 2018;23(1):107-123. doi: 10.3233/CBM-181459.
Accumulating studies have revealed that microRNAs (miRs) play a critical role in the development and progression of nasopharyngeal carcinoma (NPC), which is a disease with a remarkable racial and geographical distribution. In our study, through the alteration in the expression of microRNA-185 (miR-185) in NPC cells by microarray-based gene expression profiling, we subsequently evaluated its ability to influence NPC cells and associated mechanism.
The expressions of miR-185 and HOXC6 in NPC and paracancerous tissues collected from patients with NPC were detected. The CNE-2 cells with the lowest miR-185 among the five NPC cell lines (CNE-1, CNE-2, HNE-1, HNE-2, and 5-8F) were selected and transfected with a series of mimic or inhibitor of miR-185, or shRNA-against HOXC6. The Kaplan-Meier method was used to analyze the survival of patients. Besides, the reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used to determine the levels of related genes/proteins. By means of cell counting kit-8 (CCK-8) assay, transwell assay, flow cytometry, and AO staining, the influences miR-185 has on the processes associated with NPC, including cell proliferation, invasion, apoptosis and autophagy were evaluated.
NPC was observed to decrease miR-185 but increase HOXC6. Dual luciferase reporter gene assay demonstrated that HOXC6 is a target gene of miR-185. Increased mRNA and protein levels of Bax, caspase-3, LC3 and Beclin1 and reduced levels of HOXC6, TGF-β1, mTOR, Cyclin D1, PCNA, Bcl-2 were found by overexpression of miR-185. High expression of miR-185 and low expression of HOXC6 had longer survival time of NPC patients. Overexpressed miR-185 enhanced cell apoptosis and autophagy, and reduced cell proliferation and invasion, while miR-185 inhibitor was observed to have induced effects on the CNE-2 cells.
Overall, the data show that miR-185 could negatively target HOXC6 to suppress cell proliferation, promotes apoptosis and autophagy through inhibiting TGF-β1/mTOR axis in NPC. Thus, miR-185 is useful strategy for the treatment of NPC.
越来越多的研究表明，微小 RNA（miRs）在鼻咽癌（NPC）的发生和发展中起着关键作用，而 NPC 是一种具有显著种族和地域分布特征的疾病。在本研究中，我们通过基于微阵列的基因表达谱分析改变 NPC 细胞中 microRNA-185（miR-185）的表达，随后评估其影响 NPC 细胞的能力及其相关机制。
检测 NPC 患者癌组织及癌旁组织中 miR-185 和 HOXC6 的表达。在 5 种 NPC 细胞系（CNE-1、CNE-2、HNE-1、HNE-2 和 5-8F）中，选择 miR-185 表达最低的 CNE-2 细胞，并转染一系列 miR-185 模拟物或抑制剂或 shRNA 靶向 HOXC6。采用 Kaplan-Meier 法分析患者的生存情况。此外，采用逆转录定量聚合酶链反应（RT-qPCR）和 Western blot 分析检测相关基因/蛋白的水平。通过细胞计数试剂盒-8（CCK-8）检测、Transwell 检测、流式细胞术和 AO 染色，评估 miR-185 对与 NPC 相关的过程的影响，包括细胞增殖、侵袭、凋亡和自噬。
观察到 NPC 降低 miR-185 但增加 HOXC6。双荧光素酶报告基因检测表明 HOXC6 是 miR-185 的靶基因。过表达 miR-185 后，Bax、caspase-3、LC3 和 Beclin1 的 mRNA 和蛋白水平升高，HOXC6、TGF-β1、mTOR、Cyclin D1、PCNA 和 Bcl-2 的水平降低。高表达 miR-185 和低表达 HOXC6 的 NPC 患者生存时间更长。过表达 miR-185 增强了细胞凋亡和自噬，降低了细胞增殖和侵袭，而 miR-185 抑制剂对 CNE-2 细胞产生了诱导作用。
总体而言，数据表明 miR-185 可通过负向靶向 HOXC6 抑制 TGF-β1/mTOR 轴抑制 NPC 细胞增殖，促进细胞凋亡和自噬。因此，miR-185 是治疗 NPC 的一种有前途的策略。
