TF and breast carcinoma: Interestingly, among the top 20 enriched TF binding motifs, we found that AP2 and SP1 were listed as the two most significantly enriched TFs in breast cancer cells, whereas AP1 was listed as the top enriched TF in leiomyoma cells; and SP1 and AP1 have been reported to be enriched proximal ER or GR targets in various cell types [30], [33], [47].