c-Jun-dependent β3GnT8 promotes tumorigenesis and metastasis of hepatocellular carcinoma by inducing CD147 glycosylation and altering N-glycan patterns

β3GnT8, a key polylactosamine synthase, plays a vital role in progression of various types of human cancer. The role of β3GnT8 in hepatocellular carcinoma (HCC) and the underlying mechanisms, however, remain largely unknown. In this study, we found that β3GnT8 and polylactosamine were highly expressed in HCC tissues compared with those in adjacent paracancer tissues. Overexpression of β3GnT8 promoted while knockdown of β3GnT8 inhibited HCC cell invasion and migration in vitro. Importantly, enhanced tumorigenesis was observed in nude mice inoculated with β3GnT8-overexpressing HCC cells, suggesting that β3GnT8 is important for HCC development in vitro and in vivo. Mechanistically, β3GnT8 modulated the N-glycosylation patterns of CD147 and altered the polylactosamine structures in HCC cells by physically interacting with CD147. In addition, our data showed the c-Jun could directly bind to the promoter of β3GnT8 gene and regulate β3GnT8 expression. β3GnT8 regulated HCC cell invasion and migration in a C-Jun-dependent manner. Collectively, our study identified β3GnT8 as a novel regulator for HCC invasion and tumorigenesis. Targeting β3GnT8 may be a potential therapeutic strategy against HCC.