LncRNA-00941在肝癌间充质干细胞调控肿瘤干细胞自我更新中的作用及机制研究

Whether liver cancer associated mesenchymal stem cells (LC-MSCs) can modulate liver cancer stem cells remains unclear. Recently, more and more lncRNAs are found playing pivotal roles in tumor ontogenesis. Whether lncRNAs can particapate in mesenchymal stem cell microenvironment regualting liver cancer stem cell or not is still an open question. Our previous research demonstrated that LC-MSCs significantly promoted hepatocellular carcinoma metastasis. Based on these results, we further found that LC-MSCs promoted the proliferation of liver tumor sphere and enhanced the surface marker of cancer stem cells. In the limiting dilution analysis, LC-MSCs enhanced tumor formation and tumor metastasis in vivo.Through the lncRNA microarray analysis, we identify that lncRNA-00941 was significantly upregualted in HCC cells by LC-MSCs coculture. It was also highly expressed in liver cancer stem cells and HCC samples. Based on these above results, we propose the hypothesis that lncRNA-00941 may play an important role in LC-MSCs modulating the self-renewal of liver cancer stem cells. To verify this hypothesis, we will explore the role and mechanism of lncRNA-00941 in LC-MSCs regulating liver cancer stem cells self-renewal and to find which cytokine secreted from LC-MSCs can upregulate the expression of lncRNA-00941, and to optimize the intervention strategies.The deep understanding of the lncRNA's role in the crosstalk between MSC niche and liver cancer stem cells will provide new targets for HCC therapy.

肝癌组织微环境中的间充质干细胞（MSC）如何调控肝癌干细胞（CSC）的功能尚未明了。近年来，长链非编码RNA（lncRNA）在肿瘤发生发展中的作用日益被重视，那么lncRNA是否参与肝癌MSC调控肿瘤干细胞的功能呢？我们发现肝癌MSC促进肝癌转移，在此基础上，我们进一步证明肝癌MSC促进肿瘤球（sphere）增殖和增加CSC的比例, 且肝癌MSC促进肿瘤梯度稀释后肝癌形成及体内转移。lncRNA芯片发现lncRNA-00941在MSC处理的肝癌细胞高表达，在肝癌CSC球及肝癌标本高表达，我们推测"lncRNA-00941可能在肝癌MSC调控肿瘤CSC自我更新中发挥重要作用"。为此，本项目将从MSC微环境的视角探讨lncRNA-00941如何调控肝癌CSC的自我更新及分子机制，鉴定肝癌MSC分泌的细胞因子如何参与lncRNA-00941的表达及相应的干预策略，以期为肝癌微环境干预提供新的靶点

我们前期研究结果证实肝癌组织存在间充质干细胞（MSC），且肝癌MSC能够促进肝癌增殖。在此基础上，我们进一步探讨肝癌MSC是否调控肝癌干细胞及其转移能力。我们的结果表明：（1）肝癌MSC共培养促进肝癌干细胞的比例，体内转移及促进发生上皮-间质转换（EMT）；（2）进一步通过lncRNA 芯片寻找肝癌MSC调控肝癌干细胞增殖及转移的可能机制，共培养后肝癌MSC使的三种肝癌细胞系均差异表达的lncRNA共57个，其中lncRNA-00941上调表达非常显著，由于lncRNA-00941在lncRNA的数据库中并没有功能注释，我们将其命名为MSC upregulated factor–lncRNA,简称lncRNA-MUF，我们采用脾脏注射转移模型、过表达和RNA干涉、RNA-pulldown、质谱分析、RNA免疫共沉淀等进行功能和机制研究证实lncRNA-MUF在肝癌MSC微环境调控肝癌干细胞及转移过程中发挥重要作用。我们的研究从肝癌MSC微环境的视角探讨lncRNA如何调控肝癌转移，以期为肝癌的微环境干预提供新的靶点。在本课题的资助下，以第一作者兼通讯作者在肿瘤学权威期刊Cancer Research，SCI影响影子9.322；作为通讯作者发表在纳米肿瘤著名期刊ACS Appl Mater Interfaces，SCI影响影子8.097，作为第一作者在Oncology reports发表，SCI影响因子2.976。作为通讯作者在Nature Communication修稿文章一篇，作为主要参与作者发表影响因子大于10的论文5篇，申请发明专利3项，授权专利1项。