STAT5A and breast cancer: In mice models, the overexpression of STAT5A has been associated with the initiation of breast cancer, a contradictory observation to the tumor suppressive effects of STAT5, where the STAT5 signaling augments the expression TGF- α and in turn enhances the expression of EGFR predisposing the development of malignant changes (Halim et al., 2020).