Yang Zhihong, Sun Baocun, Li Yanlei, Zhao Xiulan, Zhao Xueming, Gu Qiang, An Jindan, Dong Xueyi, Liu Fang, Wang Yong
Department of Pathology, Tianjin Medical University, Tianjin 300070, China; Department of Pathology, General Hospital of Tianjin Medical University, Tianjin 300052, China.
Department of Pathology, Tianjin Medical University, Tianjin 300070, China; Department of Pathology, Cancer Hospital of Tianjin Medical University, Tianjin 300060, China; Department of Pathology, General Hospital of Tianjin Medical University, Tianjin 300052, China.
Exp Mol Pathol. 2015 Jun;98(3):352-9. doi: 10.1016/j.yexmp.2015.03.030. Epub 2015 Mar 26.
Zinc finger E-box binding homeobox 2 (ZEB2), an epithelial-mesenchymal transition (EMT) regulator, has been involved in invasion and metastasis of human tumor. Although EMT may be involved in vasculogenic mimicry (VM) formation, no reports describing the relation between ZEB2 and VM are available. We hypothesize that ZEB2 may promote VM formation in hepatocellular carcinoma (HCC).
Paraffin-embedded tumor tissue samples from 92 patients were immunostained with anti-ZEB2 antibody. We found that the ZEB2 nuclear expression was significantly associated with VM formation and metastasis. Patients with VM and ZEB2 nuclear expression had a shorter survival period than those without expression. In vitro, ZEB2 overexpression significantly enhanced cell motility, invasiveness, and VM formation of HepG2 cells. ZEB2 upregulation also increased VE-cadherin, Flt-1, and Flk-1 expression and activated MMPs. ZEB2 knockdown inhibited cell motility, invasiveness, and VM formation in Bel7402 cells. ZEB2 knockdown also decreased VE-cadherin, Flt-1, and Flk-1 expression and MMP activity. In addition, EMT in HepG2 cells was induced by TGF-β1 treatment, and the kinetics of expression of EMT markers and regulators were assessed by Western blot analysis. The expression of ZEB2 increased significantly, and VM formation was promoted.
ZEB2 can promote VM formation through the EMT pathway. Our findings may represent a novel therapeutic target in HCC.
锌指E盒结合同源框蛋白2(ZEB2)是一种上皮-间质转化(EMT)调节因子,已被证实参与人类肿瘤的侵袭和转移。尽管EMT可能参与血管生成拟态(VM)的形成,但尚无关于ZEB2与VM之间关系的报道。我们推测ZEB2可能促进肝细胞癌(HCC)中的VM形成。
用抗ZEB2抗体对92例患者的石蜡包埋肿瘤组织样本进行免疫染色。我们发现ZEB2的核表达与VM形成和转移显著相关。有VM和ZEB2核表达的患者生存期比无表达的患者短。在体外,ZEB2过表达显著增强了HepG2细胞的运动性、侵袭性和VM形成。ZEB2上调还增加了血管内皮钙黏蛋白(VE-cadherin)、血管内皮生长因子受体1(Flt-1)和血管内皮生长因子受体2(Flk-1)的表达并激活了基质金属蛋白酶(MMPs)。ZEB2敲低抑制了Bel7402细胞的运动性、侵袭性和VM形成。ZEB2敲低也降低了VE-cadherin、Flt-1和Flk-1的表达以及MMP活性。此外,用转化生长因子-β1(TGF-β1)处理诱导HepG2细胞发生EMT,并通过蛋白质免疫印迹分析评估EMT标志物和调节因子的表达动力学。ZEB2的表达显著增加,并促进了VM形成。
ZEB2可通过EMT途径促进VM形成。我们的研究结果可能代表了HCC的一种新的治疗靶点。