核受体FXR和miR-122均是重要的抗肿瘤分子，但miR-122是否受到FXR的调控参与抗肿瘤作用目前未见报道。因此，本项目在发现人和鼠肝癌细胞中，FXR活化后能显著上调miR-122的表达，促进miR-122的转录活性；并且临床病人肝细胞癌组织标本和肝癌细胞中FXR和miR-122的表达明显降低；生物信息学分析miR-122启动子区存在FXR可能结合位点的基础上，拟借助报告基因检测、EMSA、Super EMSA、ChIP等技术，明确miR-122是FXR的一个新靶基因，从而阐明FXR促进miR-122表达的分子机制；进而经CCK-8、Transwell、细胞凋亡检测等体外实验以及RNAi等体内实验研究FXR促进miR-122表达的分子机制和抗肝癌作用，阐明"FXR-miR-122通路"是FXR的一个新抗肝癌机制，为探讨以"FXR-miR-122通路"为靶标的抗肝癌策略提供新的科学依据

Both farnesoid X receptor(FXR) and micro RNA 122(miR-122) are important anti-tumor molecules. However, it is unclear whether FXR plays its anti-tumor role via up-regulating miR-122. Our preliminary data for the first time showed that FXR could dramatically induce miR-122 expression and significantly enhance its transcriptional activity. Moreover, we foud that both FXR and miR-122 levels were decreased in HCC patient samples and HCC cell lines. Bioinformatic analysis showed that there were potential binding sites for FXR in human miR-122 promoter region. In the present study, we will confirm that miR-122 is a novel target gene of FXR by using a number of technology such as reporter assy, electrophoretic mobility shift assay(EMSA), super EMSA, chromatin immunoprecipitation, etc.. The above experiments will reveal the mechanism by which FXR upregulates miR-122 expression. Subsequently, we will investigate the miR-122 induction by FXR activation in vivo, and study the significance of FXR-mediated miR-122 upregulation in the suppression of HCC in vitro using many methods including CCK-8, Transwell, apoptosis detection, and so on. Furthermore, we will perform the in vivo experiments to evaluate the importance of miR-122 upregulation in FXR-mediated anti-HCC effect. So that we hope to reveal that the FXR/miR-122 pathway is a novel anti-HCC mechanism of FXR. The present study may provide a new sight for exploring novel therapeutic strategy for HCC by targeting FXR/miR-122 pathway.