Similarly, Klf4 is required to maintain the cell morphology of mammary epithelial cells: while its loss induces EMT-like morphological changes, forced expression of Klf4 in invasive breast cancer cells induces epithelial differentiation by directly repressing the expression of Snail1, a potent repressor of E-cadherin gene expression, and by directly binding to the E-cadherin promoter and up-regulating E-cadherin expression [26]. Here, KLF4 is linked to breast cancer.