As shown in Figure 3A and Figure S2A, WISP3 repressed the transcriptional activity of β‐catenin/TCF in a dose‐dependent manner, while WISP3 had very little effect on the activation of ATF2 luciferase reporter in both HEK293T and HCC cells (Figure S2B‐D). Here, CCN6 is linked to hepatocellular carcinoma.