LncRNA ST8SIA6-AS1 promotes hepatocellular carcinoma progression by regulating MAGEA3 and DCAF4L2 expression

Hepatocellular carcinoma (HCC) is the most prevalent type of liver cancer. In this study, we aimed to explore the role and mechanism of lncRNA ST8SIA6-AS1 in HCC. We found that ST8SIA6-AS1 was upregulated in HCC tissues and associated with poorer overall survival of HCC patients from TCGA. Moreover, ST8SIA6-AS1 was highly expressed in HCC in-house tissues and cells, and ST8SIA6-AS1 upregulation was related to aggressive tumor phenotypes and the poor overall survival of HCC patients. Downregulation of ST8SIA6-AS1 suppressed HCC cell proliferation, migration and invasion in vitro and restrained HCC tumorigenesis in vivo. In terms of mechanism, ST8SIA6-AS1 regulated melanoma-associated antigen (MAGE)-A3 (MAGEA3) and DDB1-and Cul4-associated factor 4-like 2 (DCAF4L2) expression, and rescue experiments verified that ST8SIA6-AS1 played a protumorigenic role in HCC via the regulation of MAGEA3 and DCAF4L2. ST8SIA6-AS1 partly directly bound to miR-129–5p and functioned as a competing endogenous RNA (ceRNA), subsequently facilitating the expression of the miR-129–5p target gene DCAF4L2 to play its role in HCC. In summary, our results identified ST8SIA6-AS1 as an oncogenic lncRNA predicting poor clinical outcomes of patients with HCC. These findings suggest that ST8SIA6-AS1 is a potential therapeutic target for HCC.