[Deubiquitinating enzyme MINDY1 is an independent risk factor for the maintenance of stemness and poor prognosis in liver cancer cells].

Objective: To explore the key deubiquitinating enzymes that maintain the stemness of liver cancer stem cells and provide new ideas for targeted liver cancer therapy. Methods: The high-throughput CRISPR screening technology was used to screen the deubiquitinating enzymes that maintain the stemness of liver cancer stem cells. RT-qPCR and Western blot were used to analyze gene expression levels. Stemness of liver cancer cells was detected by spheroid-formation and soft agar colony formation assays. Tumor growth in nude mice was detected by subcutaneous tumor-bearing experiments. Bioinformatics and clinical samples were examined for the clinical significance of target genes. Results: MINDY1 was highly expressed in liver cancer stem cells. The expression of stem markers, the self-renewal ability of cells, and the growth of transplanted tumors were significantly reduced and inhibited after knocking out MINDY1, and its mechanism of action may be related to the regulation of the Wnt signaling pathway. The expression level of MINDY1 was higher in liver cancer tissues than that in adjacent tumors, which was closely related to tumor progression, and its high expression was an independent risk factor for a poor prognosis of liver cancer. Conclusion: The deubiquitinating enzyme MINDY1 promotes stemness in liver cancer cells and is one of the independent predictors of poor prognosis in liver cancer.目的： 探索维持肝癌干细胞干性的关键去泛素化酶，为肝癌靶向治疗提供新思路。 方法： 采用CRISPR Screen高通量筛选技术筛选肝癌干细胞干性维持的去泛素化酶。采用RT-qPCR和Western blot分析基因表达水平；使用成球实验、软琼脂克隆形成实验检测肝癌细胞干性；裸鼠皮下荷瘤实验检测肿瘤生长情况；生物信息学及临床样本检测目标基因的临床意义。 结果： MINDY1在肝癌干细胞中高表达，敲除MINDY1后干性标志物表达下调、细胞自我更新能力显著降低，且抑制了移植瘤的生长，其作用机制可能与调控Wnt信号通路有关。MINDY1在肝癌组织中表达水平高于癌旁，与肿瘤进展密切相关，其高表达是一个肝癌不良预后的独立危险因素。 结论： 去泛素化酶MINDY1促进肝癌细胞干性，是一个肝癌不良预后的独立预测因子。.