However, overexpression of RAC1B did not increase the number of proliferative cells in the normal small intestine nor in the early adenomas (Figs. 3D and S2A) and did not increase the expression of canonical Wnt target genes such as Axin2, Tcf7, Lef1 or Ctnnb1 (Fig. S2B). Here, CTNNB1 is linked to adenoma.