Interestingly, EGR-1 is also a target of miR-181 involved in TGF-β-mediated tumor mammosphere formation [94,95], and is upregulated in breast cancer cells expressing high level of NF-κB-induced kinase, which has been associated to a more “stemness” phenotype, promoting cancer expansion and mammosphere formation [96]. The gene discussed is EGR1; the disease is breast cancer.