T cell factor-4 (Tcf-4) plays an important role in development and carcinogenesis. It directly binds to cytosolic β-catenin and facilitate its translocation to the nucleus. In the nucleus, these complexes induce expression various target genes. The adenovirus expresses a dominant negative TCF4. Reference: He TC., et al., Science. 1998 Sep 4;281(5382):1509-12.