结直肠癌肝转移(CLM)是影响预后的关键，申请人所在课题组前期针对临床组织样本进行组学研究，筛查了编码基因并获得了丰富研究成果，然而CLM过程中长链非编码基因的系统分析和具体机制探索仍是个空白。在前期工作中，申请人利用肝转移的肠癌组织进行芯片筛查并结合大样本验证，原创性地鉴定了1个促肠癌细胞侵袭转移的新lncRNA，即lncRNA-CLMAT3。生物信息学分析表明其邻近的SPARC编码基因可能是潜在作用位点。我们后续的组织和细胞层面工作进一步提示CLMAT3可通过下调SPARC介导CLM的发生、发展。在此基础上，本项目拟重点研究CLMAT3调控SPARC的精细机制，从直接相互作用或通过中间蛋白调节来系统探讨其调控形式，从而阐明CLMAT3介导SPARC影响CLM的分子途径。本研究将有助于深入理解CLM的lncRNA机制，为靶向CLMAT3分子的CLM预后判断及个体化治疗奠定理论基础。

Liver metastasis is a pivotal factor on colorectal cancer prognosis, and the mechanism is still not clear. Long noncoding RNA (lncRNA) has recently become a hot research field internationally in tumor metastases, however it was not analysed deeply especially in colorectal liver metastases (CLM). In our preliminary work, by using lncRNA array for screen and test in samples of colorectal cancer with various liver metastases, we found one novel lncRNA, named with lncRNA-CLMAT3. This over-expressed lncRNA could promote colorectal cancer cell migration and invasion, which had been tested and verified in cell and nude mice. Moreover, we found a known coding gene-SPARC, associated with tumor metastatic, was adjacent to lncRNA-CLMAT3. Our preliminary work further showed that lncRNA-CLMAT3 might play a key role in progression of CLM by inhibiting the expression of SPARC gene. On the above base, this project aimed to study the mechanism of how the lncRNA-CLMAT3 regulate the SPARC, where two way would be designed: one way is the lncRNA-CLMAT3 may directly link up with SPARC; the other way is the lncRNA-CLMAT3 may first recruit one median protein, then together combine with SPARC and adjust the expression. This study could help not only to rich the mechanism of CLM, but also to establish a theoretical basis of CLM prognosis and therapeutics based on lncRNA.

长链非编码RNA具有重要的细胞功能并在人类疾病中发挥重要的调控作用，然而其在肠癌肝转移中的作用目前尚知之甚少。在本研究中，我们主要分析肠癌肝转移组织中是否存在差异表达的lncRNA，并进一步分析其临床价值。通过基因芯片分析了同时性、异时性肝转移组织以及无转移组织中的差异lncRNA，基于生物信息学的分析，并进一步进行定量PCR的验证，并对目的lncRNA分析其临床特征及预后情况。结果显示，通过分析1332例肝转移组织，发现40个差异lncRNA可能与肝转移相关，值得进一步探索。其中，三个验证后的新的lncRNA，命名为lncRNA-CLMAT 1-3.其中 lncRNA-CLMAT3与肝转移与否、淋巴结转移显著相关。高表达lncRNA-CLMAT3的患者较低表达者具有较差的中位生存。多因素分析显示，lncRNA-CLMAT3是预后的独立风险因子。以上提示lncRNA-CLMAT3与肠癌肝转移显著相关，同时是其生存预后的独立预测分子。同时目前对于该lncRNA-CLMAT3在肠癌细胞中的增殖调控作用情况未知，我们认为理论上其能发挥促进肠癌细胞增殖的作用。进一步的研究中发现，较正常组织项目，肠癌组织中lncRNA-CLMAT3显著高表达，体外实验显示抑制其表达可抑制肠癌细胞的增殖，此外我们的研究显示，这种增殖抑制作用主要由于敲低lncRNA-CLMAT3后阻断了G0/G1期，并增强了细胞凋亡。此外，敲低lncRNA-CLMAT3可增强Cdh1的表达，进一步通过增强Skp2蛋白的泛素化促进P27的富集。总结来说，我们的研究发现敲低lncRNA-CLMAT3后，通过影响细胞周期复合物进而抑制细胞的增殖。