Altogether, these data will help to understand the extent of the pleiotropism exhibited by NDRG1 and suggest that it can be involved in the maintenance of different CSCs subpopulations in TNBC, depending on the tissue of origin of the cell lines (primary tumor or pleural effusion), and their grade of differentiation into a more aggressive phenotype induced by TGFβ1. This evidence concerns the gene NDRG1 and Pleural effusion.