Hence, because NDRG1 was reported to enhance resistance to chemotherapy 43, we hypothesized that NDRG1 could have a role on CSCs by TGFβ1 in TNBC cells derived from primary tumor after long-term exposure to TGFβ1, whereas shorter stimulation would be enough for those cells which are derived from pleural effusion. Here, TGFB1 is linked to Pleural effusion.