TcdB^FBD inhibits Wnt signaling in human breast cancer cell lines.

(A) Left panel: phylogenetic analysis of human FZD proteins [15]; right panel: qRT-PCR analysis of Fzds in MDA-MB-231 cells. (B) Cell viability measured by the MTT assay showed that TcdBFBD did not exhibit cytotoxicity to the indicated human cell lines (error bars indicate mean ± SEM, 3 independent experiments). (C) Representative images of clonogenic growth of PaTu8988s and HPAF-II cells cultured in the presence of TcdBFBD (150 nM) or LGK974 (100 nM). (D) Representative images of sphere formation assay in PaTu8988s and HPAF-II cells cultured in the presence of TcdBFBD (150 nM) or LGK974 (100 nM). (E) Quantitation of colony numbers and sphere formation from (C and D), error bars indicate mean ± SEM, n = 4. (F) Immunoblot analysis of active β-catenin expression in PaTu8988s and HPAF-II cells cultured in the presence of TcdBFBD (150 nM) or LGK974 (100 nM). Actin serves as a loading control. (G) Quantitative analysis of expression of active β-catenin expression in (F). NS, not significant;*, p S1 Data. (PDF)