VDR and breast carcinoma: Our group has shown that 1,25(OH)2D3 downregulates the expression of myoepithelial/basal markers, such as P-cadherin, smooth muscle α-actin, and α6 and β4 integrins in a panel of breast carcinoma cells, and that Vdr−/− mice express higher levels of P-cadherin and smooth muscle α-actin in the mammary gland than wt littermates [100].