Ye Tao, Xu Jing, Du Ling, Mo Wenhui, Liang Yiming, Xia Jinglin
Minhang hospital, Fudan University, Shanghai, China.
Shanghai Cancer Center, Fudan University, Shanghai, China.
Cell Physiol Biochem. 2017;41(4):1584-1595. doi: 10.1159/000470824. Epub 2017 Mar 27.
BACKGROUND/AIMS: Dysregulation of ubiquitin-associated protein 2-like (UBAP2L) has been reported in tumors, but its role in hepatocellular carcinoma (HCC) progression is unclear.
The expression levels of UBAP2L in HCC tissues and HCC cell lines were detected by western blot and quantitative real-time (qRT) PCR. The effects of UBAP2L expression on HCC cell biological traits, including migration and invasion, were investigated by wound healing assay and matrigel transwell assay. Simultaneously, the expression of epithelial-mesenchymal transition (EMT) markers including E-cadherin, CK-18, N-cadherin, Vimentin, Claudin7 and the promoter activity of E-cadherin were detected by western blot and qRT-PCR. Subsequently, role of SNAIL1 in UBAP2L-mediated EMT and the mechanism underlying UBAP2L-mediated SNAIL1 expression were further investigated.
UBAP2L was overexpressed in human HCC tissues compared with peri-tumoral tissues. Downregulation of UBAP2L inhibited migration, invasion and the EMT in highly metastatic HCC cell lines. Furthermore, UBAP2L knockdown inhibited expression of the transcriptional repressor SNAIL1 and its ability to bind to the E-cadherin promoter via SMAD2 signaling pathway, which in turn resulted in increased E-cadherin expression. Additionally, bioinformatics analysis showed that expression of UBAP2L is correlated with poor prognosis in patients with HCC.
UBAP2L plays a critical role in maintenance of the metastatic ability of HCC cells via SNAIL1 Regulation and is predictive of a poor clinical outcome.
背景/目的：泛素相关蛋白2样蛋白（UBAP2L）在肿瘤中存在失调现象，但其在肝细胞癌（HCC）进展中的作用尚不清楚。
采用蛋白质免疫印迹法和定量实时聚合酶链反应（qRT-PCR）检测HCC组织及HCC细胞系中UBAP2L的表达水平。通过划痕实验和基质胶侵袭实验研究UBAP2L表达对HCC细胞生物学特性（包括迁移和侵袭）的影响。同时，采用蛋白质免疫印迹法和qRT-PCR检测上皮-间质转化（EMT）标志物E-钙黏蛋白、细胞角蛋白18、N-钙黏蛋白、波形蛋白、紧密连接蛋白7的表达以及E-钙黏蛋白的启动子活性。随后，进一步研究SNAIL1在UBAP2L介导的EMT中的作用以及UBAP2L介导SNAIL1表达的机制。
与癌旁组织相比，UBAP2L在人HCC组织中高表达。下调UBAP2L可抑制高转移性HCC细胞系的迁移、侵袭及EMT。此外，敲低UBAP2L可抑制转录抑制因子SNAIL1的表达及其通过SMAD2信号通路与E-钙黏蛋白启动子结合的能力，进而导致E-钙黏蛋白表达增加。另外，生物信息学分析显示，UBAP2L的表达与HCC患者的不良预后相关。
UBAP2L通过调控SNAIL1在维持HCC细胞转移能力中起关键作用，且可预测不良临床结局。
