CTNNB1 and hepatocellular carcinoma: After TERT, the most recurrently mutated (~30%) gene in HCC is CTNNB1 (Catenin Beta 1), which codes for β-catenin, a protein which acts as a key intracellular signal transducer in the canonical Wnt/β-catenin signaling pathway21,29–31,54,55.