IGF1 and breast cancer: Glucocorticoid agonists like dexamethasone and hydrocortisone, lactogenic hormones, insulin, insulin growth factor (IGF)-1, and IGF-2 are also reported as inducer of NIS expression in BC cells.14, 15, 16 Signaling pathways like mitogen-activated protein kinase (MAPK) can also contribute positively in regulating NIS function in BC.17