Xie Lisha, Jiang Tao, Cheng Ailan, Zhang Ting, Huang Pin, Li Pei, Wen Gebo, Lei Fanghong, Huang Yun, Tang Xia, Gong Jie, Lin Yunpeng, Kuai Jianke, Huang Weiguo
Cancer Research Institute, Hengyang Medical College of University of South China, Hengyang 421001, Hunan Province, China.
Department of Yiyang Central Hospital, Yiyang, 413000, Hunan Province, China.
Curr Mol Pharmacol. 2019;12(2):105-114. doi: 10.2174/1874467212666181218113930.
Alterations in microRNAs (miRNAs) are related to the occurrence of nasopharyngeal carcinoma (NPC) and play an important role in the molecular mechanism of NPC. Our previous studies show low expression of 14-3-3σ (SFN) is related to the metastasis and differentiation of NPC, but the underlying molecular mechanisms remain unclear.
Through bioinformatics analysis, we find miR-597 is the preferred target miRNA of 14-3-3σ. The expression level of 14-3-3σ in NPC cell lines was detected by Western blotting. The expression of miR-597 in NPC cell lines was detected by qRT-PCR. We transfected miR-597 mimic, miR-597 inhibitor and 14-3-3σ siRNA into 6-10B cells and then verified the expression of 14-3-3σ and EMT related proteins, including E-cadherin, N-cadherin and Vimentin by western blotting. The changes of migration and invasion ability of NPC cell lines before and after transfected were determined by wound healing assay and Transwell assay.
miR-597 expression was upregulated in NPC cell lines and repaired in related NPC cell lines, which exhibit a potent tumor-forming effect. After inhibiting the miR-597 expression, its effect on NPC cell line was obviously decreased. Moreover, 14-3-3σ acts as a tumor suppressor gene and its expression in NPC cell lines is negatively correlated with miR-597. Here 14-3-3σ was identified as a downstream target gene of miR-597, and its downregulation by miR-597 drives epithelial-mesenchymal transition (EMT) and promotes the migration and invasion of NPC.
Based on these findings, our study will provide theoretical and experimental evidences for molecular targeted therapy of NPC.
微小RNA（miRNA）的改变与鼻咽癌（NPC）的发生有关，并在NPC的分子机制中发挥重要作用。我们之前的研究表明，14-3-3σ（SFN）的低表达与NPC的转移和分化有关，但其潜在的分子机制仍不清楚。
通过生物信息学分析，我们发现miR-597是14-3-3σ的首选靶标miRNA。通过蛋白质免疫印迹法检测NPC细胞系中14-3-3σ的表达水平。通过qRT-PCR检测NPC细胞系中miR-597的表达。我们将miR-597模拟物、miR-597抑制剂和14-3-3σ siRNA转染到6-10B细胞中，然后通过蛋白质免疫印迹法验证14-3-3σ和上皮-间质转化（EMT）相关蛋白（包括E-钙黏蛋白、N-钙黏蛋白和波形蛋白）的表达。通过伤口愈合试验和Transwell试验确定转染前后NPC细胞系迁移和侵袭能力的变化。
miR-597在NPC细胞系中表达上调，并在相关NPC细胞系中得到修复，表现出强大的肿瘤形成作用。抑制miR-597表达后，其对NPC细胞系的作用明显减弱。此外，14-3-3σ作为一种肿瘤抑制基因，其在NPC细胞系中的表达与miR-597呈负相关。在这里，14-3-3σ被确定为miR-597的下游靶基因，miR-597对其下调驱动上皮-间质转化（EMT）并促进NPC的迁移和侵袭。
基于这些发现，我们的研究将为NPC的分子靶向治疗提供理论和实验依据。
