Role of epigenetic mechanisms in epithelial-to-mesenchymal transition of breast cancer cells

The epithelial-to-mesenchymal transition (EMT) is a crucial process during normal development that allows dynamic and reversible shifts between epithelial and mesenchymal cell states. Cancer cells take advantage of the complex, interrelated cellular networks that regulate EMT to promote their migratory and invasive capabilities. During the past few years, evidence has accumulated that indicates that genetic mutations and changes to epigenetic mechanisms are key drivers of EMT in cancer cells. Recent studies have begun to shed light on the epigenetic reprogramming in cancer cells that enables them to switch from a noninvasive form to an invasive, metastatic form. The authors review the current knowledge of alterations of epigenetic machinery, including DNA methylation, histone modifications, nucleosome remodeling and expression of microRNAs, associated with EMT and tumor progression of breast cancer cells. Last, existing and upcoming drug therapies targeting epigenetic regulators and their potential benefit for developing novel treatment strategies are discussed.