STAT3 and breast cancer: STAT3 activation of target genes such as TGF-β1 and hypoxia inducible factor- (HIF-) 1α has been linked to EMT reprograming [132] and several recent studies have shown that TAM-secreted IL-6, EGF, or MFGE-8 can activate STAT3 signaling in CSCs of breast cancer [109, 133], HCC [100], or colon cancer [134].