Figure 3. Vitamin D interferes with β-catenin induced gene expression via different pathways in different cell types. Left panel: in cancer cells vitamin D impairs the Wnt/β-catenin signaling pathway. One of these mechanisms relays on the association of the complex VDR/1,25(OH)2D3 to β-catenin to induce VDR-regulated gene expression avoiding β-catenin dependent gene expression. Right panel: in some other non-cancer cell types vitamin D exerts an activating effect of the Wnt signaling pathway by upregulating the expression of the Fzd co-activator Lrp5 or by repressing the expression of the Wnt inhibitors DKK1 y Sfrp2 [116, 171].