CTNNB1 and neoplasm: Treatment with BC2059 resulted in decreased whole-cell binding of β-catenin to TBL1 in CTNNB1-mutated desmoid cells; however, no significant effect was observed in CTNNB1 wild-type cells (Fig 3A), probably because desmoid tumor cell lines lacking detectable CTNNB1 mutation could primarily be composed of fibroblasts cells.