When analyzing both case cohorts together the network with the highest scores (35, 31) centered on TP53, β-estradiol and CTNNB1 (encoding β–catenin, the oncogenic nuclear accumulation of which occurs in several malignancies, including breast cancer [21]) and the other around β-estradiol (Figure 1, Table 3). This evidence concerns the gene CTNNB1 and breast cancer.