NDRG1 and Pleural effusion: To clarify and answer inconsistencies among different reports, and the NDRG1 controversy, and based on our results showing that NDRG1 could be involved in TGFβ signaling pathway, we hypothesized that NDRG1 could exhibit different roles depending on the origin of the TNBC cell lines (established from primary tumor or pleural effusion/metastatic lesion) under stimulation with TGFβ1.