Iscan Evin, Ekin Umut, Yildiz Gokhan, Oz Ozden, Keles Umur, Suner Aslı, Cakan-Akdogan Gulcin, Ozhan Gunes, Nekulova Marta, Vojtesek Borivoj, Uzuner Hamdiye, Karakülah Gökhan, Alotaibi Hani, Ozturk Mehmet
Izmir Biomedicine and Genome Center, Izmir 35000, Turkey.
Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir 35000, Turkey.
Cancers (Basel). 2021 Feb 13;13(4):783. doi: 10.3390/cancers13040783.
Hepatocyte dedifferentiation is a major source of hepatocellular carcinoma (HCC), but its mechanisms are unknown. We explored the p73 expression in HCC tumors and studied the effects of transcriptionally active p73β (TAp73β) in HCC cells. Expression profiles of p73 and patient clinical data were collected from the Genomic Data Commons (GDC) data portal and the TSVdb database, respectively. Global gene expression profiles were determined by pan-genomic 54K microarrays. The Gene Set Enrichment Analysis method was used to identify TAp73β-regulated gene sets. The effects of TAp73 isoforms were analyzed in monolayer cell culture, 3D-cell culture and xenograft models in zebrafish using western blot, flow cytometry, fluorescence imaging, real-time polymerase chain reaction (RT-PCR), immunohistochemistry and morphological examination. TAp73 isoforms were significantly upregulated in HCC, and high p73 expression correlated with poor patient survival. The induced expression of TAp73β caused landscape expression changes in genes involved in growth signaling, cell cycle, stress response, immunity, metabolism and development. Hep3B cells overexpressing TAp73β had lost hepatocyte lineage biomarkers including ALB, CYP3A4, AFP, HNF4α. In contrast, TAp73β upregulated genes promoting cholangiocyte lineage such as YAP, JAG1 and ZO-1, accompanied with an increase in metastatic ability. Our findings suggest that TAp73β may promote malignant dedifferentiation of HCC cells.
肝细胞去分化是肝细胞癌（HCC）的主要来源，但其机制尚不清楚。我们探究了HCC肿瘤中p73的表达情况，并研究了转录活性p73β（TAp73β）对HCC细胞的影响。分别从基因组数据共享库（GDC）数据门户和TSVdb数据库收集p73的表达谱和患者临床数据。通过泛基因组54K微阵列确定全局基因表达谱。采用基因集富集分析方法来识别TAp73β调控的基因集。使用蛋白质免疫印迹法、流式细胞术、荧光成像、实时聚合酶链反应（RT-PCR）、免疫组织化学和形态学检查，在单层细胞培养、3D细胞培养和斑马鱼异种移植模型中分析TAp73亚型的作用。TAp73亚型在HCC中显著上调，p73高表达与患者生存率低相关。TAp73β的诱导表达导致参与生长信号、细胞周期、应激反应、免疫、代谢和发育的基因的表达格局发生变化。过表达TAp73β的Hep3B细胞失去了包括ALB、CYP3A4、AFP、HNF4α在内的肝细胞谱系生物标志物。相反，TAp73β上调了促进胆管细胞谱系的基因，如YAP、JAG1和ZO-1，同时转移能力增强。我们的研究结果表明，TAp73β可能促进HCC细胞的恶性去分化。
