GSK3B and hepatocellular carcinoma: Phosphorylation of GSK3β at threonine 43 by Erk (extracellular-signal-regulated kinase), primes GSK3β for phosphorylation at Ser9 by p90RSK, and mediates HBV-X protein (HBX)-induced upregulates β-catenin in human hepatocellular carcinoma cells [58].