He Lu, Wang Guo-Peng, Guo Jing-Ying, Chen Zhong-Rui, Liu Ke, Gong Shu-Sheng
Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China.
Front Mol Neurosci. 2021 Dec 17;14:809878. doi: 10.3389/fnmol.2021.809878. eCollection 2021.
The vestibular sensory epithelium of humans and mice may degenerate into a layer of flat cells, known as flat epithelium (FE), after a severe lesion. However, the pathogenesis of vestibular FE remains unclear. To determine whether the epithelial-mesenchymal transition (EMT) participates in the formation of vestibular FE, we used a well-established mouse model in which FE was induced in the utricle by an injection of streptomycin into the inner ear. The mesenchymal and epithelial cell markers and cell proliferation were examined using immunofluorescence staining and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The function of the EMT was assessed through transcriptome microarray analysis. The results demonstrated that mesenchymal cell markers (α-SMA, S100A4, vimentin, and Fn1) were upregulated in vestibular FE compared with the normal utricle. Robust cell proliferation, which was absent in the normal status, was observed in the formation of FE. Microarray analysis identified 1,227 upregulated and 962 downregulated genes in vestibular FE. Gene Ontology (GO) analysis revealed that differentially expressed genes (DEGs) were highly associated with several EMT-related GO terms, such as cell adhesion, cell migration, and extracellular matrix. Pathway enrichment analysis revealed that DEGs were enriched in the EMT-related signaling pathways, including extracellular matrix (ECM)-receptor interaction, focal adhesion, PI3K/Akt signaling pathway and cell adhesion molecule. Protein-protein interaction networks screened 20 hub genes, which were , , and . Most of these genes are reportedly involved in the EMT process in various tissues. The mRNA expression level of hub genes was validated using qRT-PCR. In conclusion, the present study indicates that EMT plays a significant role in the formation of vestibular FE and provides an overview of transcriptome characteristics in vestibular FE.
人类和小鼠的前庭感觉上皮在遭受严重损伤后可能会退化为一层扁平细胞，即扁平上皮（FE）。然而，前庭FE的发病机制仍不清楚。为了确定上皮-间质转化（EMT）是否参与前庭FE的形成，我们使用了一种成熟的小鼠模型，通过向内耳注射链霉素在椭圆囊中诱导FE形成。使用免疫荧光染色和定量逆转录聚合酶链反应（qRT-PCR）检测间质细胞和上皮细胞标志物以及细胞增殖情况。通过转录组微阵列分析评估EMT的功能。结果表明，与正常椭圆囊相比，前庭FE中间质细胞标志物（α-SMA、S100A4、波形蛋白和Fn1）上调。在FE形成过程中观察到了正常状态下不存在的强烈细胞增殖。微阵列分析确定了前庭FE中有1227个上调基因和962个下调基因。基因本体论（GO）分析显示，差异表达基因（DEG）与几个与EMT相关的GO术语高度相关，如细胞粘附、细胞迁移和细胞外基质。通路富集分析显示，DEG富集于与EMT相关的信号通路，包括细胞外基质（ECM）-受体相互作用、粘着斑、PI3K/Akt信号通路和细胞粘附分子。蛋白质-蛋白质相互作用网络筛选出20个枢纽基因，分别是 、 和 。据报道，这些基因中的大多数参与了各种组织中的EMT过程。使用qRT-PCR验证了枢纽基因的mRNA表达水平。总之，本研究表明EMT在前庭FE的形成中起重要作用，并提供了前庭FE转录组特征的概述。
