ESR1 and breast carcinoma: A direct effect of ERα as a transcription factor on the expression of Wnt ligands, modulators and targets has been described by many authors: the ligands Wnt4, Wnt5A and Wnt7A have been shown to be induced by estradiol [53] [54] [50] [55] [56]; the Wnt inhibitor DKK1 was shown to be inhibited by estrogens in bone forming osteoblasts [57] and in the hippocampal CA1 region [58] and last, the Wnt-target gene WISP2 (Wnt-1 induced signaling pathway protein 2) was shown to be upregulated through direct interaction of activated ERα with its promoter region in human breast cancer cells [59].