Figure 4.

Secreted Frizzled-related protein-1 (SFRP1) is a suppressor of Wnt protein that binds to Wnt protein in a competitive manner that prevents binding with the transmembrane Fzd receptor. With decreased SFRP1 expression, the Wnt protein associates with the Fzd receptor, after which the Wnt pathway is activated. The active Wnt pathway induces β-catenin destruction through the E-cadherin complex and translocation to the nucleus where it can interact with TCF/LEF and activate the Vimentin promoter. Vimentin is then synthesized and released into the extracellular matrix [64,65].