Fig. 3.

A hypothetical model in which CK2β is at center stage in the regulation of epithelial plasticity. a Snail1 and Foxc2 are master transcription regulators that trigger the formation of a signaling network responsible for establishing and maintaining mesenchymal cell phenotypes. In epithelial cells, both GSK3β and CK2 can negatively regulate Snail1 stability through its hierarchal phosphorylation. CK2-mediated phosphorylation of Foxc2 promotes its cytoplasmic retention. Importantly, CK2-dependent phosphorylation of both transcription factors is mediated by the holoenzyme and thus requires the presence of CK2β. b Silencing of CK2β or unbalanced expression of CK2 subunits in response to changes in the microenvironment leads to inefficient phosphorylation of Snail1 and Foxc2, thereby leading to their nuclear translocation and to EMT induction associated with enhanced migratory potential and acquisition of apoptosis resistance