TCF4 and breast cancer: Concordantly, the expression levels of multiple downstream targets of Wnt/β-catenin signaling, namely cyclin D1, c-MYC, TCF4 and LEF1, and nuclear β-catenin, were increased in the miR-1229–overexpressing breast cancer cells but decreased in the miR-1229–silenced breast cancer cells (Supplementary Figure S1A–S1C).