基于胞外囊泡长链非编码RNA的肝细胞癌新型肿瘤标志物筛选与功能研究

As vectors for intercellular information exchange, the potential role of extracellular vesicles　(EV) in hepatocellular cancer (HCC) growth and progression has been widely investigated. An increasing number of long noncoding RNA (lncRNA) have alterations in expression in HCC, such as lnc ZEB1-AS1 and ZFAS1，which expressed aberrantly in the HCC tissue and cell lines and had a significant relevance to tumor metastasis and patient’s survival. However, the expression and functional role of the lncRNA within the HCC-derived EV are still unclear. It offers promise for new biomarkers and new therapy for HCC to study these tumor-specific lncRNAs within EV. So, we are going to screen and analyze the tumor-specific lncRNAs within HCC-derived EV using RNA-sequencing and real time PCR method, and to elucidate the role and mechanism of these lncRNAs in tumor growth and metastasis at a cellular and animal level. The ultimate aim is to seek a new tumor marker and potential treatment way for HCC to improve the overall survival of HCC patients.

肝细胞肝癌（HCC）的胞外囊泡（EV）可通过所携带的长链非编码RNA（lncRNA）等成分在细胞间传递信息并调节细胞功能，参与HCC的生长及转移。我们以往研究表明HCC中存在多种lncRNA的异常表达，如lncRNA ZEB1-AS1与ZFAS1在肝癌组织中表达异常且与肿瘤转移预后密切相关，但这些lncRNA在EV中的表达情况及功能尚不清楚。研究HCC来源EV中lncRNA的表达及功能不仅为HCC新型肿瘤标志物的发现提供了可能，还可为阐明HCC发生发展机理以及HCC治疗提供新思路。因此我们拟利用最新的二代基因测序方法对HCC来源EV中已知肿瘤相关lncRNA进行筛选分析，并对筛选出的核心lncRNA在细胞水平与动物水平阐明其参与HCC生长及侵袭转移机理，旨在寻求基于血清EV的lncRNA新型HCC肿瘤标志物及治疗新方法，以提高HCC患者的早期诊断及治疗生存率，该课题具有重要的临床应用价值。

肝细胞癌患者死亡率高，因缺乏有效肿瘤标记物而早期诊断率低，且近年来5年总生存率并无明显改善。本课题借助高通量测序技术筛查肝细胞癌患者血清外泌体中差异表达的长链非编码RNA，筛选到有望作为早期诊断和判断预后的新型肿瘤标记物lncRNA-AC145207.5，.课题进一步通过体内外功能试验证实lncRNA-AC145207.5可促进肝癌细胞增殖、迁移、侵袭，并抑制凋亡，并阐明此lncRNA可能通过内源性竞争性抑制作用下调下游靶基因miR-137的表达，上调下游靶向分子PLCB1，从而促进肿瘤侵袭转移的分子机制。该课题对于寻找肝细胞癌早期诊断及判断预后的新型肿瘤标志物以及新型的抗肿瘤治疗通路提供了思路，具有一定的临床意义与应用价值