Chen Jing, Ge Si-Jia, Feng Hai-Juan, Wu Shu-Zhen, Ji Ran, Huang Wei-Rong, Huang Wei, Lu Cui-Hua
Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong, China.
Research Center of Clinical Medicine, Nantong University, Affiliated Hospital of Nantong University, Nantong, China.
J Clin Transl Hepatol. 2022 Apr 28;10(2):207-218. doi: 10.14218/JCTH.2021.00101. Epub 2021 Jul 8.
Although activation of hepatic stellate cells (HSCs) plays a central role in the development of liver fibrosis, the mechanism underlying the activation of HSCs remains unclear. Keratin 17 (KRT17), a member of the intermediate filament family, can regulate tumor cell proliferation and migration. The current study aimed to elucidate the role of KRT17 in the activation of HSCs and the mechanisms underlying liver fibrosis.
The expression of KRT17 was determined using immunohistochemistry in tissue microarray. Western blotting and qRT-PCR assays were used to determine the KRT17 expression in fibrotic liver tissues obtained from human subjects and mice. LX-2 cells were treated with TGF-β1 recombinant protein and adipocyte differentiation mixture (MDI) mix to induce and reverse LX-2 cell activation, respectively, in order to explore the correlation between KRT17 and HSC activation. Additionally, cell proliferation and migration abilities of LX-2 cells transfected with KRT17-overexpressing plasmid or small interfering RNA were determined using CCK-8, flow cytometry, Transwell, and wound healing assays. Finally, rescue assay was used to explore the role of KRT17 in HSC activation and epithelial-mesenchymal transition (EMT).
The expression of KRT17 was higher in the human and mouse fibrotic liver tissues than in healthy liver tissues, and it was positively correlated with HSC activation. Upregulated KRT17 enhanced proliferation, migration, HSC activation and EMT in LX-2 cells, while knockdown of KRT17 reversed these effects. TGF-β1 recombinant protein accelerated KRT17-mediated EMT, HSC activation and proliferation, while TGF-β1 inhibitor counteracted the effect of KRT17 .
KRT17 promoted HSC activation, proliferation and EMT in hepatic fibrosis probably via TGF-β1 signaling, and KRT17 might serve as a therapeutic target for the treatment of liver fibrosis.
尽管肝星状细胞（HSC）的激活在肝纤维化发展中起核心作用，但HSC激活的潜在机制仍不清楚。角蛋白17（KRT17）是中间丝家族成员，可调节肿瘤细胞增殖和迁移。本研究旨在阐明KRT17在HSC激活中的作用及肝纤维化的潜在机制。
采用免疫组化法在组织芯片中检测KRT17的表达。利用蛋白质免疫印迹法和qRT-PCR检测人及小鼠纤维化肝组织中KRT17的表达。分别用转化生长因子-β1（TGF-β1）重组蛋白和脂肪细胞分化混合物（MDI）处理LX-2细胞以诱导和逆转LX-2细胞激活，从而探讨KRT17与HSC激活之间的相关性。此外，使用CCK-8、流式细胞术、Transwell和伤口愈合实验检测转染KRT17过表达质粒或小干扰RNA的LX-2细胞的增殖和迁移能力。最后，采用拯救实验探讨KRT17在HSC激活和上皮-间质转化（EMT）中的作用。
人及小鼠纤维化肝组织中KRT17的表达高于健康肝组织，且与HSC激活呈正相关。KRT17上调增强了LX-2细胞的增殖、迁移、HSC激活和EMT，而敲低KRT17则逆转了这些作用。TGF-β1重组蛋白加速了KRT17介导的EMT、HSC激活和增殖，而TGF-β1抑制剂抵消了KRT17的作用。
KRT17可能通过TGF-β1信号通路促进肝纤维化中HSC的激活、增殖和EMT，KRT17可能成为治疗肝纤维化的靶点。
