ESR1 and breast cancer: It is worthy to note that miR-190b, the highest up-regulated miRNA in ER+ tumors, was also the highest miRNA expressed in ER+ breast cancer cell lines, with a FC of 43 compared to 8 for the second higher up-regulated miRNA, miR-342-5p (Table 7), and that this up-regulation was observed in most of ER+ breast cancer cell lines (Fig. 1) confirming thus that miR-190b may have an important role in ER-dependent tumorigenesis.