NEDD4 and hepatocellular carcinoma: Kai Li et al. observed that NEDD4 was upregulated in tissues with insufficient HCC ablation and promoted HCC cell migration, suggesting that NEDD4 mediates tumor progression by enhancing TGF-β signaling through direct binding to the TGF-β type I receptor (TGFBR 1) and the formation of a K27-conjugated ubiquitin chain at lysine 391 (i.e., inadequate ablation induced HCC progression owing to the upregulation of NEDD4).