Downregulation of PEDF is associated with increased EMT in bladder and breast cancer tiusses.29, 30 PEDF overexpression in MD-231 breast cancer cells decreased fibronectin and migration but did not change the EMT phenotype in our recent study.31 This cell type-specific function has been observed with other proteins, such as Bmi-1 and ILEI.25, 32 Thus, PEDF-participated EMT may be existed in a cell type-dependent manner. This evidence concerns the gene BMI1 and breast cancer.