Zhang J H, Wu X, Wang T T, Wang Z S
Department of Oncology, The First Affiliated Hospital of Bengbu Medical University, Bengbu 233004, China.
Zhonghua Gan Zang Bing Za Zhi. 2024 Aug 20;32(8):734-743. doi: 10.3760/cma.j.cn501113-20240407-00176.
To study the SUV3 gene role during the process of occurrence and advancement of hepatocellular carcinom. The The differences in SUV3 expression between hepatocellular carcinoma tissues and normal liver tissues were compared by analyzing transcriptome sequencing data from TCGA and GTEx databases. SUV3 knockdown in different hepatocellular carcinoma cells was performed using RNA interference technology. Overexpression vectors were constructed to overexpress SUV3 in different hepatocellular carcinoma cells. The SUV3 regulatory effect was studied on proliferation, migration, and invasion of hepatocellular carcinoma cells. A subcellular fraction isolation approach was used to investigate whether SUV3 knockdown resulted in the release of mitochondrial DNA into the cytoplasm. Quantitative reverse transcription PCR was applied to investigate whether SUV3 knockdown affected PD-L1 expression. The two groups were compared using a two-tailed -test. The TCGA database analysis revealed that SUV3 expression was higher in hepatocellular carcinoma tissues than in normal liver tissues, and the prognosis of patients with high SUV3 expression in hepatocellular carcinoma tissues was poor. The quantitative RT-PCR results showed that SUV3 expression was higher in hepatocellular carcinoma tissues than that in paracancerous liver tissue. The MTS assay showed that with SUV3 knockdown, the proliferation rate was significantly lower in hepatocellular carcinoma cells than that of the control hepatocellular carcinoma cells (<0.01). The proliferation rate was significantly higher in SUV3-overexpressed hepatocellular carcinoma cells than that of control hepatocellular carcinoma cells (<0.01). Cell scratch assay and cell migration and invasion assay showed that SUV3 knockdown inhibited the migration and invasion of hepatocellular carcinoma cells (<0.01), while SUV3 overexpression promoted the migration and invasion of hepatocellular carcinoma cells (<0.05). SUV3 Knockdown led to a decrease in the overall level of mtDNA (<0.01) in accompanied by an increase in mtDNA level in the cytoplasm (<0.01), indicating that SUV3 knockdown led to mitochondrial DNA leakage into the cytoplasm. SUV3 knockdown resulted in elevated PD-L1 expression (<0.001), and overexpression of TREX1 in SUV3 knockdown cells decreased mtDNA levels in the cytoplasm and inhibited SUV3 knockdown, resulting in elevated PD-L1 expression, indicating that SUV3 knockdown induced PD-L1 expression by increasing cytoplasmic DNA levels. The SUV3 gene may play an oncogenic function in hepatocellular carcinoma cells.
研究SUV3基因在肝细胞癌发生发展过程中的作用。通过分析来自TCGA和GTEx数据库的转录组测序数据，比较肝细胞癌组织与正常肝组织中SUV3表达的差异。利用RNA干扰技术在不同的肝癌细胞中敲低SUV3。构建过表达载体以在不同的肝癌细胞中过表达SUV3。研究SUV3对肝癌细胞增殖、迁移和侵袭的调控作用。采用亚细胞分级分离方法研究敲低SUV3是否导致线粒体DNA释放到细胞质中。应用定量逆转录PCR研究敲低SUV3是否影响PD-L1表达。两组采用双侧t检验进行比较。TCGA数据库分析显示，肝细胞癌组织中SUV3表达高于正常肝组织，肝细胞癌组织中SUV3高表达患者的预后较差。定量RT-PCR结果显示，肝细胞癌组织中SUV3表达高于癌旁肝组织。MTS检测显示，敲低SUV3后，肝癌细胞的增殖率显著低于对照肝癌细胞（P<0.01）。SUV3过表达的肝癌细胞增殖率显著高于对照肝癌细胞（P<0.01）。细胞划痕试验以及细胞迁移和侵袭试验显示，敲低SUV3抑制了肝癌细胞的迁移和侵袭（P<0.01），而SUV3过表达促进了肝癌细胞的迁移和侵袭（P<0.05）。敲低SUV3导致线粒体DNA总体水平降低（P<0.01），同时细胞质中线粒体DNA水平升高（P<0.01），表明敲低SUV3导致线粒体DNA泄漏到细胞质中。敲低SUV3导致PD-L1表达升高（P<0.001），在敲低SUV3的细胞中过表达TREX1可降低细胞质中线粒体DNA水平并抑制敲低SUV3导致的PD-L1表达升高，表明敲低SUV3通过增加细胞质DNA水平诱导PD-L1表达。SUV3基因可能在肝癌细胞中发挥致癌作用。
