Cell-permeable. A potent inhibitor of the β-catenin-responsive transcription (CRT) in the nucleus. iCRT5 inhibits Wnt responsive STF16 luciferase (STF16-Luc) with an IC₅₀ of 18 nM. It acts by disrupting the interaction between β-catenin and TCF4, possibly by direct binding to β-catenin. However, it displays minimal or less prominent effect on non-canonical Wnt signaling and other pathways such as Hh, JAK/STAT, and Notch signaling.