外泌体miR-188-3p激活肝星状细胞形成肝转移前微环境促进结直肠癌肝转移的作用及分子机制研究

Liver is the most common metastatic organ for colorectal carcinoma (CRC). Pre-metastatic niche is a favorable microenvironment in secondary or distant organs and tissue sites for colonization of metastatic tumor cells. However, little is known about the function and mechanism on CRC cells create a pre-metastatic niche to promote liver metastasis. Our preliminary results had shown that hepatic stellate cell (HSC) was activated in liver with liver metastases of CRC, and the quantity of activated HSC increased with the progress of metastasis. We had demonstrated that CRC cells with high liver metastatic potential could activate HSC to promote liver metastasis by forming a pre-metastatic niche via exosomes, and miR-188-3p secreted by CRC cells might activate HSC to promote liver metastasis by creating a pre-metastatic niche. Based on preliminary research, we plan to use clinical specimen, in vitro assays with cell lines, in vivo assays with in situ colorectal cancer model in nude mice to verify that colorectal carcinoma cells create a favorable microenvironment by activating HSC via exosomal miR-188-3p. And then, we use bioinformatics software or gene microarray to screen exosomal miR-188-3p-targeted gene and further verify the signal pathway in HSC by a serial in vitro and in vivo assays. Finally, we explore the role of activated HSC in remodeling the pre-metastatic niche to promote liver metastasis. Then assays including RayBio Human Cytokine Antibody Array, in vitro and in vivo assays are used to screen and verify the molecular mechanism, and further validated its clinical significance by clinical specimen. Overall, our study will provide the useful theorectical basis in preventing and treating liver metastases of CRC.

肝脏是结直肠癌最常见的转移器官。转移前微环境促进肿瘤靶向器官转移，而仍对结直肠癌细胞重塑肝转移前微环境促进肝转移的作用机制知之甚少。我们前期研究发现结直肠癌肝转移的肝组织中肝星状细胞（HSC）被激活，且HSC活化数量随转移进展而增加。并通过体内外试验证实高肝转移潜能的结直肠癌细胞分泌外泌体激活HSC形成肝转移前微环境促进肝转移，且结直肠癌细胞可能通过外泌体miR-188-3p激活HSC形成肝转移前微环境。结合前期研究，本研究拟从临床血清标本、体外细胞试验、体内裸鼠原位结直肠癌模型三个层面来研究外泌体miR-188-3p激活HSC的作用，并利用生物信息学或基因芯片筛选靶基因并行系统的体外、体内研究验证其作用信号通路。最后探索激活的HSC对转移前微环境的重塑作用，利用细胞因子抗体蛋白芯片筛选关键因子并体外内试验验证，进一步在临床样本中验证，阐明分子机制，为研发防治肝转移的新方案奠定坚实的基础。

肝脏是结直肠癌最常见的转移器官。转移前微环境促进肿瘤靶向器官转移，而仍对结直肠癌细胞重塑肝转移前微环境促进肝转移的作用机制知之甚少。肝星状细胞（HSC）是肝脏内最主要的间质细胞，我们研究结果显示结直肠癌肝转移的肝组织中肝星状细胞（HSC）被激活，且HSC活化数量随转移进展而增加。高转移潜能的结直肠癌细胞可激活HSC形成转移前微环境促进肝转移，也已证实高转移潜能的结直肠癌细胞分泌外泌体miR-188-3p激活HSC促进肝转移。且机制研究进一步证实miR-188-3p靶向ARRDC3基因激活形成HSC形成转移前微环境。本研究阐明了高转移潜能的结直肠癌细胞分泌外泌体miR-188-3p激活HSC形成转移前微环境促进肝转移的作用，为研发预防肝转移的新策略奠定了坚实的理论基础。