CircRNA-smad4.10经吸附miR-145-5p/miR-205-5p上调亲本基因SMAD4形成的双重负反馈促进肝癌侵袭转移的机制研究

The mechanisms of invasion and metastasis of hepatocellular carcinoma (HCC) remain largely unknown. Studies have showed that circRNAs are closely related to the occurrence and development of cancer. However, the relationship between circRNAs and invasion and metastasis of HCC remain unclear. In our previous study, we found that 412 circRNAs were dysregulated in HCC by the high throughput microarray assay, and the highest expression circ-smad4.10 was closely related to the pathological stage and grade of HCC by 30 cases of clinical samples; By employing bioinformatics software, it was predicted that there is the double negative feedback between circ-smad4.10, miR-145-5p/miR-205-5p, and SMAD4. Therefore, based on our previous work, the project will verify the relationship between circ-smad4.10 and the invasion and metastasis of HCC; also will illuminate the mechanisms that the circ-smad4.10-miR-145-5p/miR-205-5p-SMAD4 double negative feedback promotes HCC invasion and metastasis; will explore the therapeutic effect of HCC invasion and metastasis by inhibiting circ-smad4.10. The implementation of this project will help to elucidate the mechanisms of HCC that circ-smad4.10 promotes the invasion and metastasis of HCC, and provide the scientific basis of finding the novel therapeutic target for HCC.

肝癌易侵袭和转移,其机制未明。研究表明circRNAs与癌症的发生发展密切相关，但与肝癌侵袭转移的关系未知。前期我们通过高通量芯片技术在肝癌中筛选出412个失调的circRNAs，经30例临床样本验证发现增高最明显的circ-smad4.10与肝癌病理分期和分级等密切关联；生物信息学预测circ-smad4.10、miR-145-5p/miR-205-5p和亲本基因SMAD4之间存在双重负反馈。因此，本项目拟在前期工作基础上进一步明确circ-smad4.10与肝癌侵袭转移的关系；阐明circ-smad4.10经吸附miR-145-5p/miR-205-5p上调亲本基因SMAD4形成的双重负反馈促进肝癌侵袭转移的机制；探索抑制circ-smad4.10对于肝癌侵袭转移的治疗作用。本课题的实施将有助于阐明circ-smad4.10促进肝癌侵袭转移的机理，为发现新的肝癌治疗靶点奠定基础。

Circular RNAs (circRNAs)是一种共价闭环的新型非编码RNA，研究表明circRNAs与多种肿瘤的生物或者病理过程密切相关。但是，许多失调的circRNAs在肝癌中的作用及其机制仍然未知。本课题中，我们通过高通量芯片结合实时定量PCR技术从肝癌中筛选出一种高表达的circRNA：circRNA-smad4.10，发现增高circRNA-smad4.10与肝癌侵袭和转移呈正相关；采取过表达/沉默策略，经体内外实验证实，circRNA-smad4.10过表达促进了肝癌的侵袭和转移。生物信息学分析circRNA-smad4.10能吸附miR-145-5p/miR-205-5p。经过荧光报告酶基因、RIP、细胞凋亡等实验，阐明了circRNA-smad4.10经吸附miR-145-5p/miR-205-5p双重调节SMAD4促进肝癌侵袭和转移的机制；并初步证实，抑制circRNA-smad4.10具有阻止肝癌生长的作用。本课题的研究为筛选新的肝癌标志物和治疗靶点具有重要意义。