27-hydroxycholesterol induces the transition of MCF7 cells into a mesenchymal phenotype.

A decrease in the expression of E-cadherin and β-catenin, paralleling the loss of adherens junction complex, was observed in MCF7 cells exposed for longer than 48 h to 2 µM 27-hydroxycholesterol (27OHC), indicating an epithelial-mesenchymal transition (EMT). Upon removal of 27OHC from the culture medium, the cells released by the exposure of 72 h to the oxysterol grew as loosely packed cell groups. In these cells, accumulation of E-cadherin and β-catenin in the cytoplasm and the prolonged expression of epidermal growth factor receptor 2 (EGFR2/neu) in the plasma membrane were observed, suggesting that the acquired phenotype was related to the expression of this tyrosine kinase-growth factor receptor. The results presented here are discussed on the basis of the claimed relationship between 27OHC, hypercholesterolemia, macrophage infiltration and therapy-resistant ERα+ breast cancer incidence.