DKK4 and hepatocellular carcinoma: In addition, the T3–THRs–TREs complex induces expression of Dickkopf (DKK) 4, which antagonizes Wnt/β-catenin signaling in hepatocellular carcinoma cell lines (HCC), suggesting a role for T3 in tumor suppression and unraveling the T3/DKK4/Wnt/β-catenin pathway as a possible therapeutic target in HCC (Liao et al., 2012; Figure 2A).