FBXL6 and hepatocellular carcinoma: Our results suggest that elevated FBXL6 expression promotes VRK2 phosphorylation-dependent TKT polyubiquitination and activation and thereby enhances ROS-mTOR-mediated upregulation of VRK2 and PD-L1 expression and immune evasion, ultimately promoting HCC metastasis (Fig. 7k).