We also suggest that it is important to find out whether the NF-κB/Snail/YY1/RKIP/PTEN dysregulated circuitry found in the EMT phenotype is also shared in cancer stem cells such that YY1 inhibitors will be helpful to prevent the development of a metastatic tumor from stem cells and induce the death of stem cells [31]. The gene discussed is PTEN; the disease is neoplasm.