We observed the downregulation of the Wnt pathway ligand Wnt-3A and the Wnt-dependent transcription factor TCF7L1 in Sdc-1-depleted MCF-7 cells, which is in accordance with our previous observation of a downregulation of the Wnt-coreceptor LRP6 in Sdc-1-depleted breast cancer cells [16]. This evidence concerns the gene SDC1 and breast cancer.