MicroRNA miR-147b promotes tumor growth via targeting UBE2N in hepatocellular carcinoma

As the subfamily of noncoding RNA, microRNAs (miRNAs) broadly regulate the development of cancers, while their dysregulation and function in human hepatocellular carcinoma (HCC) remains largely unclear. Here, we found the expression level of microRNA-147b (miR-147b) is increased aberrantly in HCC tumor tissues, and its expression positively correlates to the tumor severity. In both MTT and colony formation assay, knockdown of miR-147b dramatically inhibits in vitro proliferation of HCC cell lines. More interestingly, we also performed in vivo tumorigenesis assay and found that miR-147b can regulate in vivo tumorigenesis in nude mice xenograft models. The ubiquitin-conjugating enzyme E2N (UBE2N) was identified directly and functionally targeted by miR-147b. The mRNA level of UBE2N is increased in HCC tumors or cell lines. Restoring UBE2N expression level in tumor cells leads to inhibition of cell proliferation, which mimics the effect upon miR-147b knockdown in the same cells. These data elucidated the oncogenic role of miR-147b in HCC development and progression with therapeutic target potentials.