缺氧代谢产物L-2-羟戊二酸（L-2-HG）通过调控组蛋白甲基化修饰增强肝细胞生长因子受体（MET）表达促进肝癌转移的机制研究

临床观察发现肝动脉栓塞等“缺氧事件”促进肝癌转移，其机制尚不清楚。课题组通过代谢组学分析，发现缺氧诱导产生大量代谢产物L-2-HG。其有增强肝癌细胞转移的能力。转录组测序发现L-2-HG处理后MET基因转录显著增强。结合文献报道及TCGA数据库分析，L-2-HG可能通过抑制组蛋白去甲基化酶KDM2A，增加H3K36Me来促进MET转录。课题将通过体内外实验，揭示缺氧诱导的L-2-HG/KDM2A/H3K36Me/MET轴促进肝癌转移。在细胞、动物、临床标本中运用质谱检测，验证缺氧时L-2-HG增加。运用qPCR、WB证实L-2-HG上调MET。运用RNAi、药物抑制等手段，阐明MET在L-2-HG促进转移中的贡献。运用基因敲除、过表达证实去甲基化酶KDM2A的作用。运用染色质免疫沉淀，检测L-2-HG引起的MET转录起始点附近H3K36Me1/2的改变。研究有望阐明缺氧诱导肝癌转移新机制。

The clinical study has found that hypoxia events such as transhepatic arterial embolization could promote the metastasis of liver cancer. However, its potential mechanism remains unclear. Based on metabolomics analysis, we found that hypoxia induced production of l-2-hydroxyglutarate. It can enhance the metastasis of liver cancer cells. RNA-seq showed that the transcription of MET was significantly enhanced after L-2-HG treatment. Based on literatures and TCGA database analysis, L-2-HG may promote MET transcription by inhibiting histone demethylase KDM2A and increasing methylation of H3K36. Our study will reveal the hypoxia inducible L-2-HG / KDM2A / H3K36Me / MET axis promotes liver cancer metastasis in vivo and in vitro. Mass spectrometry will be used to verify that hypoxia induces production of L-2-HG in cell lines, animal models, and clinical specimens. QPCR and western blot will be used to confirm that L-2-HG promotes the expression of MET. RNAi and MET inhibitor will be used to clarify the contribution of MET to metastasis caused by L-2-HG. The role of the demethylase KDM2A will be confirmed by knocking out and overexpressing KDM2A. Chromatin immunoprecipitation will be used to detect H3K36Me1/2 in the transcription start site of MET with or without L-2-HG. Those studies are expected to elucidate the novel mechanism of hypoxia-induced metastasis of hepatocellular carcinoma.