ESR1 and cancer: The miR-221-3p targets genes at early stage such as Annexin A1 (ANXA1), Cyclin Dependent Kinase Inhibitor 1B (CDKN1B), and multiple genes during advance-stage cancer such as CDKN1B, PTEN, Ring Finger Protein 20 (RNF20), Estrogen Receptor 1 (ESR1) and AKT3 (Fig 6; Table 1).