UBQLN1 and hepatocellular carcinoma: Mechanistic studies revealed that upregulation of UBQLN1 in sorafenib-resistant HCC cells expedited the proteasome-mediated protein degradation of peroxisome proliferator-activated receptor γ coactivator 1β (PGC1β), contributing to decreased mitochondrial biogenesis and ROS generation, finally inducing sorafenib resistance.