基于环状RNA的肝癌预后模型建立及其生物学功能的初步研究

Metastasis and recurrence are the major reasons of poor prognosis for hepatocellular carcinoma (HCC). So it is urgent to develop a sensitive and specific assessment of risk for predicting clinical outcome of HCC patients. Circular RNAs (circRNAs) may be useful prognostic markers of HCC, because they seem to be specifically expressed in a cell type or disease stage, and they are conserved and stable. We previously analyzed the expression profile of circRNAs between HCCs with venous metastases and HCCs without venous metastases. Then we chose 6 circRNAs whose combinational expression showed more than 90% average classification accuracy. Using qRT-PCR to these chip tissues, we confirmed the results of the circRNAs microarrays. Next, we will establish a prognostic model based on these 6 circRNAs using qRT-PCR. Then the prognostic efficiency of this model will be validated in a large sample. Meanwhile, hsa_circ_001387 is mostly upregulated in HCCs with venous metastases, so we will explore its functional role in HCC. We think our work will provide basis for screening patients with high probability of metastasis and recurrence, and provide new clue for pathogenesis of HCC.

肝癌患者的预后较差，其中一个重要的原因是较高的转移复发率。因此，目前急需发明一种灵敏特异的方法鉴别术后是否发生转移复发。环状RNA具有组织特异性、疾病特异性、表达稳定不易被降解等特征，有望成为鉴别肝癌预后的生物标志物。申请者前期采用环状RNA芯片，分析了肝癌转移组和未转移组的环状RNA表达谱，选择其中差异最明显的6个环状RNA，它们联合应用后的区分准确度达到了90%。随后，申请者采用qRT-PCR的方法，对这6个环状RNA的表达进行了验证，与芯片结果相一致。因此，申请者拟采用qRT-PCR法，进一步扩大样本量建立一个基于这6个环状RNA的肝癌预后模型，并且再扩大样本对模型的预测能力进行验证，为筛选肝癌转移复发高危人群提供基础数据和理论依据。除此之外，申请者拟对两组中表达差异最大的hsa_circ_001387进行初步的生物学功能研究，为阐明肝癌的发病机制提供新思路。

肝癌是世界范围内最常见，且恶性程度最高的肿瘤之一，也是重要的公共卫生问题之一，其中75-80%为肝细胞癌(HCC)。肝癌预后较差，防治术后转移复发是肝癌研究领域迫切需要解决的问题。环状rna由于其特殊的结构，不易降解，因此有望成为肝癌预后标志物。本课题组前期通过筛查17个环状rna，发现四个环状rna（hsa_circRNA_404974、hsa_circRNA_102742、hsa_circRNA_001387、hsa_circRNA_100246）在肝癌及癌旁组织中表达差异显著。进一步分析它们和肝癌生存时间后，发现hsa_circRNA_404974和hsa_circRNA_102742的不同表达水平能够预测患者的预后情况，是肝癌无病生存期和总生存期的独立预后因素。此外，研究者在细胞水平和动物水平也证明了，hsa_circRNA_404974能够抑制肝癌的转移，是肝癌可能的预后和治疗靶点。