小G蛋白RIT1通过调控有丝分裂进程促进肝细胞癌进展的机制研究

有丝分裂异常是肿瘤细胞的一个重要特征。传统的靶向微管蛋白抑制细胞分裂的化疗药物虽然能有效杀死肿瘤细胞，但存在严重的副作用。我们前期发现小G蛋白RIT1在肝细胞癌组织中的表达明显高于癌旁组织，临床病理资料分析表明RIT1的表达与组织学分级密切相关，并且RIT1高表达的患者生存期较短。功能实验表明RIT1能促进肝细胞癌细胞的增殖与迁移侵袭，敲减RIT1能够增加索拉菲尼敏感性。初步机制分析和验证提示RIT1在肝细胞癌中参与调控细胞有丝分裂过程。.本项目拟从细胞、PDX动物模型和临床病例三个层面，采用Co-IP、质谱技术、ChIP、磷酸化芯片和形态学等技术，多角度验证RIT1通过调控有丝分裂促进肝细胞癌进展的机制，为肝细胞癌进展或预后判断提供分子标志，并探索性提出以RIT1为分型指标或靶向RIT1信号通路的肝细胞癌实验性治疗新策略。

Hypoxia triggers a series of pro-metastatic molecular events in hepatocellular carcinoma (HCC) and exacerbates the prognosis. Therefore, the molecular mechanisms driven by hypoxia have become attractive research interests. In our previous study, we found RIT1 acts as an important regulator in the progress of HCC. The expression of RIT1 is higher in HCC tissues, compared to matched non-cancerous liver tissues, and high RIT1 expression predicts a worse prognosis. The forced expression of RIT1 in HCC cell lines promotes the migration and invasion ability in vitro and lung metastasis in vivo, whereas silencing RIT1 expression reduces hypoxia-induced migration and invasion. TCGA analysis showed that RIT1 regulated mitotic division..In the present project, we will further investigate the mechanism of RIT1 using more cell lines, animal models and clinical samples. With bioinformatics analysis, we want to identify the pathway that RIT1 involved in and the transcription factor which regulates RIT1 expression using mRNA sequence, Co-IP, LC-MS, Phospho Explorer Assay, and ChIP assays. This project will expound the function and mechanism of RIT1 on progress of HCC and provide the necessary experimental basis and the correct guidance to effective treatment, prevention of recurrence and metastasis as well as the prognosis of HCC.